Restoration potential

Ecosystem management for restoration

2017-03-20T12:44:31+00:00

Authors:	Alejandro Valdecantos (CEAM),V. Ramón Vallejo (UB), Susana Bautista (UA), Matthijs Boeschoten (UU), Michalakis Christoforou (CUT), Ioannis N. Daliakopoulos (TUC), Oscar González-Pelayo (UAVR), Lorena Guixot (UA), J. Jacob Keizer (UAVR), Ioanna Panagea (TUC), Gianni Quaranta (UNIBAS), Rosana Salvia (UNIBAS), Víctor Santana (UAVR), Dimitris Tsaltas (CUT), Ioannis K. Tsanis (TUC)
Editor:	Jane Brandt
Source document:	Valdecantos, A. et al. (2016) Report on the restoration potential for preventing and reversing regime shifts. CASCADE Project Deliverable 5.2 104 pp

Degradation drivers, loss of ecosystem function and management for restoration

Degradation in drylands, especially when the pressure exceeded critical thresholds, implies losses of ecosystem functioning and diversity, and the capacity of the system to recover the original values of these altered properties determines the resilience of the system. In CASCADE we have observed that the degradation drivers considered in the project severely impacted, on occasions beyond recovery thresholds, ecosystem properties and services in the CASCADE field sites, with higher losses along the gradient of aridity represented by the field sites (Valdecantos and Vallejo 2015).

There are ecosystem properties such as the spatial distribution of vegetation that, when changed, may indicate overpassing or proximity to this eventual threshold. The intensity, both in terms of pressure and time, of degradation can affect the resilience of an ecosystem, hampering or even impeding the reversal. Whisenant (1999) proposed the existence of two degradation thresholds beyond which the natural recovery of ecosystem is extremely difficult or impossible. At the lower degree of pressure of the degradation driver, the first one is controlled by biotic interactions and the system still maintains the capacity to capture and retain resources and can be considered as a functional system. In these cases, it is only required an appropriate manipulation of the biotic component (mostly vegetation) to increase ecosystem function. If the pressure or degradation increases, a second threshold controlled by abiotic interactions can be exceeded, primary processes are not functional any longer, and the recovery of ecosystem functions requires the manipulation of the physical environment.

In all these cases restoration actions, acting as accelerated succession (Hilderbrand et al., 2005), should be envisaged to recover the integrity of the site although a complete restoration is not always possible without perpetual management (Lindig-Cisneros et al., 2003). However, some studies suggested that there is no evidence that the lower the functionality of a given ecosystem, the lower the restoration success or the higher the economic input needed (Cortina et al. 2006; Maestre et al. 2006).

In addition to these considerations, ecosystem management for restoration has to include the expected climate change scenarios as successful approaches in the past might not be effective in the future. Global climatic change represents an additional factor of uncertainty not only in the outcomes of forest plantations, but also on the very subsistence of current dryland landscapes. Alkemade et al. (2011) predicted that up 25% of the species currently present in natural landscapes of the Mediterranean Basin will disappear by 2100, being the Mediterranean shrublands one of the ecosystems in Europe most threatened by climate change projections.

Ecosystem functions assessed

Biodiversity represents a structural feature of ecosystems with direct influence in all other services (MA 2005). Monitoring biodiversity in different states of the ecosystem, identifying the local extinction of keystone species and the appearance of exotics, is extremely important as its changes may have irreversible consequences in ecosystem goods and services (Hooper et al., 2005). Restoring biodiversity and maximizing ecosystem services are priorities in the EU Biodiversity Strategy (Lammerant et al., 2013). The ecosystem services we have assessed include: i) water cycle regulation, that is a central ecosystem service for maintaining fresh water resources, controlling floods and, hence, protecting people living downstream (Vörösmarty et al., 2005), ii) nutrient cycling, regulated by a great variety of organisms and its alterations have deep impacts on ecosystem functioning (Lavelle et al., 2005), iii) soil conservation as its loss could be an irreversible process at the human and ecological scale, and its retention contribute to maintain primary productivity and to prevent harmful effects because of soil erosion (de Groot et al., 2002), iv) C sequestration in different compartments of the ecosystem and v) fire risk reduction (for the Ayora study site only).

Restoration of fire-affected areas

Within the framework of CASCADE, the two fire-affected ecosystems of the project considered restoration actions at two different time scales: within the first year after the fire when vegetation reestablishment is still very low (tree trunk removal or logging in Várzea) or several decades after the fire when the forest did not recover but a continuous shrubland was established (selective clearing and planting in Ayora). Salvage logging after fire in pine forests consists in the removal of all burned tree trunks and is one of the most common emergency actions carried out in the Mediterranean in the very early months after forest fires (de las Heras et al. 2012; Moreira et al. 2013). The main objectives of this practice are, especially, to have some return with the market value of the wood, but also to reduce fuel, to avoid erosion once the trees fall down some years after the fire, to reduce aesthetic impact, and, in case of weaken but still alive trees, to avoid pests spread (Vallejo et al. 2012). Potential negative impacts of this practice include the reductions of growth of regenerating seedlings, reductions of deadwood associated fauna, elimination of perches for birds dispersing seeds from neighbor undisturbed habitats, and reduction of microclimatic heterogeneity (Vallejo et al. 2012). There is also a risk to increase erosion associated to wood removal after fire but this impact is highly dependent on the soil properties of the area (Bautista et al. 2004).

Selective clearing of vegetation is one of the preferred management options aimed at sharply reducing fire hazard in Mediterranean fire-prone communities (Baeza et al., 2003). As compared to prescribed or controlled burning, also proposed and accepted as fuel control technique, vegetation clearing offers more positive effects especially related both to the protection of soil surface to erosion (especially when the vegetation remains are chipped and left on the ground). and resource export off-site and to the lag in the build-up of large fuel loads in the community (Baeza and Vallejo, 2008). The combination of this fuel control technique with the plantation of seedlings of late-successional species and with the ability to rapidly resprout after further disturbances (Valdecantos et al., 2009) may increase, at the same time, the resistance and the resilience to forest fires.

In the previous assessment of ecosystem services as a function of fire as degradation driver, we observed marked reductions in most ecosystem properties and services at the short term after fire (Valdecantos and Vallejo 2015). But at the long-term, burned areas recovered functionality to values similar to the Reference pine forest, with a spatial arrangement of vegetation that better conserve the resources.

Restoration of over-grazed areas

Grazing has deep impacts on ecosystem structure, composition and functioning (Milchunas and Lauenroth, 1993). Grazing exclusion is a worldwide extended practice to recover important ecosystem properties affected by overgrazing such as plant cover, vegetation and litter biomass, diversity, infiltration rate, soil fertility and soil biological properties (see Rong et al. 2014). For instance, it has been proposed as an effective management action to promote services such as soil C sequestration in areas severely affected by desertification (Li et al., 2012; Wang et al., 2016). The time elapsed since the avoidance of animals to graze as well as the ecosystem properties assessed determine the magnitude and significance of the effects of grazing exclusion. Under areas that were transformed from forest to grazed lands, fencing results in heavy and rapid forest encroachment by an increase of woody vegetation (Su et al., 2015).

In contrast, areas where the stocking rates are very low are susceptible to woody vegetation encroachment compromising grassland ecosystem types and threaten the biotic component, both plants and animals (Archer and Predick, 2014). However, there are no conclusive evidences that ecosystem services are compromised by woody vegetation encroachment while the recovery of the targeted ecosystem service after shrub management is only ephemeral and may depend on other factors. For instance, Alberti et al. (2011) observed that soil C pool reduces with clearing encroached pasturelands in moist areas but increases under dry environments.

We have observed that the CASCADE field sites affected by grazing showed a generalized decrease in diversity as compared to the reference states of the ecosystems but differences between the three grazed field sites were observed (Valdecantos and Vallejo 2015). Plant pattern in the grazed states was markedly different than in the ungrazed ones modifying the resource sink capacity of the system. LFA derived indices were lower in all Degraded sites than in their respective References suggesting a worsening of soil surface conditions and, hence, soil, water and nutrient conservation. Ecosystem services have shown important losses due to grazing in the order Randi>Messara>Castelsaraceno following a decreasing order of aridity.

Restoration of areas under multiple pressures

Albatera, with an aridity index of 0.16 and affected by multiple stressors, showed the highest relative losses of all individual and combined ecosystem services of all CASCADE field sites. The main ecosystem properties affected by degradation were those related to the sink/source spatial pattern and biodiversity. The assessment and quantification of the spatial distribution and arrangement of vegetation and, in general, of sink and source areas is especially relevant to address the restoration potential of drylands as this features have been described to determine seedling survival and growth of planted seedlings in restored semiarid sites (Urgeghe and Bautista, 2015).

Note: For full references to papers quoted in this article see

» References

Measurement of ecosystem properties and the potential for their restoration

2017-03-21T08:48:51+00:00

Authors:	Alejandro Valdecantos (CEAM),V. Ramón Vallejo (UB), Susana Bautista (UA), Matthijs Boeschoten (UU), Michalakis Christoforou (CUT), Ioannis N. Daliakopoulos (TUC), Oscar González-Pelayo (UAVR), Lorena Guixot (UA), J. Jacob Keizer (UAVR), Ioanna Panagea (TUC), Gianni Quaranta (UNIBAS), Rosana Salvia (UNIBAS), Víctor Santana (UAVR), Dimitris Tsaltas (CUT), Ioannis K. Tsanis (TUC)
Editor:	Jane Brandt
Source document:	Valdecantos, A. et al. (2016) Report on the restoration potential for preventing and reversing regime shifts. CASCADE Project Deliverable 5.2 104 pp

A common methodology was applied in all six CASCADE field sites to assess Ecosystem Services in, at least, two ecosystems representative of a healthy reference and a degraded state. However, the protocol has been adapted locally to fit singularities, constraints and possibilities of the different field sites. The general framework includes the identification of representative Reference and Degraded ecosystems according to the pressure acting in each specific site.

Table: Summary of pressures, reference and degraded ecosystems in the six CASCADE field sites

Field Site	Pressure	Reference Ecosystem	Degraded Ecosystem
Várzea, PT	Fire	Pinus pinaster forest	4-times burned areas (2-years after last fire)
Albatera, SP	Multifactor (climate, historical use and mismanagement)	Semi-steppe dry shrubland	Dwarf shrubland
Ayora, SP	Fire	Unburned Pinus pinaster and P. halepensis forest	Shrubland. Areas burned in 1979
Castelsaraceno, IT	Grazing	Productive pastureland	1.Overgrazed lands 2. Undergrazed lands
Randi, CY	Grazing	Shrubland	Unpalatable community
Messara, GR	Grazing	Shrubland	Unpalatable community

Three spatially replicated plots were established for every level of pressure in every field site to conduct the assessment of different variables of ecosystem structure and functioning. Replicated plots shared most physiographic, climatic, and edaphic variables as well as land use history. From these variables, we calculated a balanced set of ecosystem services. The effects of degradation on the ecosystem structure and function as well as on ecosystem services were derived through a comparison of the Reference with the Degraded state.

The following were measured and calculated:

- determination of plant composition,
- quantification of stand plant biomass,
- quantification of litter and belowground biomass, and
- application of the methodology of Landscape and Function Analysis.

1. Plant composition

Three 33m linear transects (as straight as possible) were deployed following the maximum slope and the line intercept method was applied. A metal rod (<5 mm diameter) was placed vertically every 50 cm along the tape (66 points per transect) and the contacts of plant species recorded. The contact at the soil level was also described (bare soil, stone, rock outcrop, litter, biological crust). Several plants may touch the rod in a particular point and all of them were recorded as well as the height where the plant contacts the rod. Note that this allows plant cover percentages above 100% due to overlapping.

Transects were deployed avoiding ‘strange’ or artificial features of the plot such as pathways, stone accumulation points, gullies. In case that the size of the plot did not allow 33-m long transects, more shorter transects were established but always totalling 100 m per plot.

2. Plant biomass

Three 1-m² quadrats (subplots) were defined in every transect. The placement of the quadrats was predefined to avoid subjective selection of microsites. For instance and in the case of a 33 m transect, we placed the subplots at 10-11 m, 20-21 m and 30-31 m (one meter away from the tape). Within these subplots we evaluated biomass of shrubs by two alternative approaches:

By clipping, drying and weighing. When possible, we cut all the individuals whose stems were within the quadrat limits and took them separately (one bag per species and subplot) to the lab. We dried the plant samples at 60ºC for 48h in an oven and weighed them. Grasses were not separated by species.
By allometric relations. There are available allometric equations for many of the most common shrub species in the Mediterranean Basin. By knowing a morphological variable (basal diameter, total height or biovolume of the plant), we calculated the biomass of the individuals. Alternatively, as was the case of some shrub species in Messara and Randi field sites, we built up our own allometric equations by harvesting, drying and weighing a pool of individuals outside the plots covering the range of plant sizes present within the plot.

" data-placement="top" data-content=" Example of systematic placement of the 1m2 subplots for biomass assessment (red quadrats)" title="">

3. Litter and belowground biomass

After harvesting grasses and shrubs, we collected the litter layer in a 25 x 25 cm sub-subplot. We avoided taking mineral soil particles in the samples as they are much heavier than the litter fractions. Samples were taken to the lab to dry them at 60ºC for 48h. In the same sub-subplot once the organic layer was removed we took a soil core of the uppermost soil (0-10, 0-15 or 0-20 cm depending on the site). Once in the lab, roots were separated from the soil by sieving and washing gently with water before drying at 60ºC for 48h.

4. Landscape and Functional Analysis (LFA)

The following is a highly synthesised description of the method used for the assessment of ecosystem functioning (extracted from Tongway and Hindley 2004).

Transects set-up: Transects started at the downslope edge of a patch following the maximum slope and as taut as possible.
Patch and inter-patch identification: By definition, patch accumulates or diverts resources by restricting flow of water, topsoil and organic matter (e.g. perennial plants , stones > 10 cm). They act as a sink of resources. But not all patches behave the same and we discriminated when possible between different patches, e.g. resprouter shrub, seeder shrub, grasses, chamaephytes. Inter-patches represent areas where resources do not accumulate and even act as net export of resources (source areas). We measured three parameters along the transects: the number of patches (sinks), the width of every single patch (at the soil level, not the canopy and up to a maximum of 10 m), and the distance between patches (inter-patch length). However, in some field sites (e.g. Ayora) the continuity of vegetation hindered clear measurements of patch characteristics.
Soil Surface Assessment: This assessment was conducted per plot in five 50 x 50 cm areas per type of identified patch and inter-patch. These five replications were distributed throughout the plot. The soil surface assessment is rapidly made by the use of simple visual indicators. These indicators are:
•    Rainsplash protection: ephemeral grasses, foliage at heights above 50 cm and litter were excluded.
•    Perennial vegetation cover
•    Litter: amount, origin and degree of decomposition. It includes annual grasses and ephemeral herbage (both standing and detached) as well as detached leaves, stems, twigs, fruit, dung, etc. There are three properties of litter that were assessed in the following order: Cover (% and thickness of the litter layer), Origin (whether it is local or transported) and Degree of Decomposition/Incorporation.
•    Cryptogam cover
•    Crust brokenness
•    Soil erosion type and severity: Five major forms of erosion were assessed: Sheet erosion (progressive removal of very thin layers of soil across extensive areas, with few if any sharp discontinuities to demarcate them), Pedestal (is the result of removing soil by erosion of an area to a depth of at least several cm, leaving the butts of surviving plants on a column of soil above the new general level of the landscape), Terracette (abrupt walls from 1 to 10 cm or so high, aligned with the local contour), Rill (channels cut by the flowing water), and Scalding (is the result of massive loss of A-horizon material in texture-contrast soils which exposes the A2 or B horizon).
•    Deposited materials: presence of soil or litter materials transported from upslope.
•    Soil surface roughness: due to soil surface micro-topography or to high grass density.
•    Surface nature: resistance to disturbance.
•    Slake test: The test was performed by gently immersing air-dry soil fragments of about 1-cm cube size in distilled water and observing the response over a period of a minute or so. If the soil floats in water (high organic matter), then it is stable (Class 4), and if it cannot be picked (loose soils) was scored as not applicable.
•    Texture

" data-placement="top" data-content=" Measurement of patch-interpatch pattern along the transect and individual measures of the patch" title="">

Spreadsheets were prepared and were filled out with the collected information and Stability, Infiltration and Nutrient Cycling indices were automatically calculated. These indices varied between 0 and 100% depending on ecosystem functionality (100% represents fully functional systems).

Table: List of the soil functional indicators and their contribution to the indices of stability, infiltration and nutrient cycling (following Tongway and Hindley 2004). x means that the indicator is scored in the calculation of the index given above.

Indicator	Indices
Indicator	Stability	Infiltration	Nutrient Cycling
Rainsplash protection	x
Perennial vegetation cover		x	x
Litter cover	x	x
Litter origin and decomposition			x
Cryptogam cover	x		x
Crust brokenness	x
Soil erosion type and severity	x
Deposited materials	x
Soil surface roughness		x	x
Surface nature	x	x
Slake test	x	x

5. Data analysis

In every CASCADE field site we conducted t-test (sites with one Reference and one Degraded state of the ecosystem) or one-way ANOVA followed by post-hoc analysis (where three ecosystem states were identified) to assess if observed differences in all composition, functional, diversity and service variables were statistically significant. We conducted Principal Component Analysis (PCA) on specific plant cover data to assess general changes in vegetation composition and cover between Degraded and Reference sites.

Table: List of ecosystem services measured, variables from which their relative states were estimated through standardization,
and the methodology used to obtain the data of the variables.

Ecosystem Service	Variables	Methodology
Water Conservation	Infiltration Index Interpatch Cover Plant Cover	LFA + Point-intersect
Soil Conservation	Stability Index Interpatch Cover Plant Cover	LFA + Point-intersect
Nutrient Cycling	Nutrient Index Litter	LFA
Carbon Sequestration	Plant biomass Root biomass Litter	Allometries + direct quantification
Biodiversity	Richness Diversity Evenness	Point-intersect

Acquired data of structural and functional ecosystem properties were then grouped into related ecosystem services through standardization. We have selected regulating and supporting services as well as biodiversity, which underpins all services. Each variable was standardized using

ZPlot = (XPlot - AvgTot) / SDTot

where ZPlot is the standardized variable, XPlot the original variable, AvgTot the average of the variable of all plots within a field site and SDTot the standard deviation of all the plots within a field site. Variables were assigned to services as they were derived from validated methodologies selected on the basis of being appropriate indicators for this service. When several variables were combined into one service, each variable was weighted equally, as all of them are considered to be good indicators for the respective service and no available information points to a better performance of any of them. The five selected ecosystem services were also weighted equally and averaged for Degraded and Reference plots in each field site as a global result of ecosystem service losses. This way, the assessment provides a baseline integrated and global evaluation based on the simplest assumption. However, it is worth mentioning that stakeholders’ preferences regarding ecosystem services could be incorporated in the assessment in the form of different weights for each service, which could yield different global outcomes.

Note: The selection of the key common indicators and assessment methods has been based on the work developed by the EU-funded PRACTICE project on ground-based assessment indicators. They represent few essential indicators that could characterize ecosystem function for a majority of drylands worldwide, mostly focusing on water and soil conservation, nutrient cycling, carbon sequestration, and biological diversity. Most provisioning and cultural services are considered to be very much context dependent (Rojo et al. 2012). Furthermore, half of the sites included in CASCADE are natural areas that are not expected to directly deliver goods. Therefore, our across-site comparative assessment of ecosystem services provision has been only based on supporting-regulating services, which together with biodiversity, are considered to be baseline services and properties that underpin other types of services (Bautista and Lamb, 2013)

Note: For full references to papers quoted in this article see

» References

Results highlights from all study sites

2017-01-26T11:59:34+00:00

Authors:	Alejandro Valdecantos (CEAM),V. Ramón Vallejo (UB), Susana Bautista (UA), Matthijs Boeschoten (UU), Michalakis Christoforou (CUT), Ioannis N. Daliakopoulos (TUC), Oscar González-Pelayo (UAVR), Lorena Guixot (UA), J. Jacob Keizer (UAVR), Ioanna Panagea (TUC), Gianni Quaranta (UNIBAS), Rosana Salvia (UNIBAS), Víctor Santana (UAVR), Dimitris Tsaltas (CUT), Ioannis K. Tsanis (TUC)
Editor:	Jane Brandt
Source document:	Valdecantos, A. et al. (2016) Report on the restoration potential for preventing and reversing regime shifts. CASCADE Project Deliverable 5.2 104 pp

" data-placement="top" data-content=" Figure 1: Locations of the six CASCADE field sites" title="">

Within the six CASCADE field sites (Figure 1), there is a clear climatic gradient (Table 1). Two of the sites fall within the humid climate, three belong to the dry sub-humid climate, and one is classified as semi-arid. The average annual rainfall ranges from 267 mm yr-¹ in Albatera to 1289 mm yr-¹ in Castelsaraceno. There are also large differences in temperatures along the field sites. Castelsaraceno is again the coldest station with average annual mean temperature below 10ºC, while the hottest field site is Randi forest in Cyprus with mean annual temperatures close to 20ºC. The two Spanish sites show the lowest aridity indices (0.16 and 0.26 in Albatera and Ayora, respectively) while Castelsaraceno and, in a lesser extent, Várzea showed the highest aridity indices (1.05 and 0.84, respectively). Therefore, in addition to types and levels of degradation pressures, the CASCADE project includes a great variety of climates, soils, land uses and land use history (Table 2) that may eventually condition the loss of ecosystem services as described in Daliakopoulos and Tsanis (2013).

Table 1: Climatic characteristics of the six CASCADE field sites

	Várzea	Albatera	Ayora	Castelsaraceno	Messara	Randi
Climate	Humid	Semi-arid	Dry sub-humid	Humid	Dry sub-humid	Dry sub-humid
Average annual rainfall (mm)	1170	267	385	1289	503	489
Average mean temperature (ºC)	13.0	18.0	14.6	9.1	17.9	19.5
Aridity Index (mm/mm)	0.84	0.16	0.26	1.05	0.31	0.29
PET (monthly)	118.6	136.0	123.4	102.5	136.0	141.5

Table 2: Summary of main properties of the six CASCADE field sites

	Varzea	Albatera	Ayora	Castelsaraceno	Messara	Randi
Elevation	450-600 m	225-310 m	830-1030 m	972-1284 m	100-230 m	90-230 m
Bedrock	Schists	Dolomites, conglomerates and sandstones	Marl and limestone colluvium, limestones	Limestones and dolomites	Limestones and marls	Marls
Soils	Cambisols	Calcisols, Cambisols and Fluvisols	Regosols, Cambisols and Leptosols	Regosols	Cambisols and Luvisols	Calcaric regosols
Land use	Forests and shrublands (and agriculture in lesser extent)	Agriculture (52%) and shrublands (24%)	Forests and shrublands	Cropland, pasturelands and forests	Croplands and shrublands	Croplands and shrublands
History	Recurrent fires (1978, 1985, 2005, 2012)	Abandonment of rainfed croplands, alpha grass harvesting and wood gathering, afforestations	Fire (1979) and abandonment of wood harvesting	Land abandonment (especially after 1990s)	Overgrazing and overexploitation of water resources	Agriculture and grazing

Similarly, the ecosystems that have been selected as references or undisturbed states of the ecosystem also show much contrasted values of key ecosystem structure and function properties (Figures 2 and 3).

" data-placement="top" data-content=" Figure 2: Total aboveground biomass (Mg ha-1) in the Reference state of the ecosystem in all CASCADE field sites. The position of the field sites is random." title="">

" data-placement="top" data-content=" Figure 3: Species richness of vascular plants (number of species/100 m²) in the Reference state of the ecosystem in all CASCADE field sites. The position of the field sites is random." title="">

Fire-Driven Landscapes

The two field sites affected by wildfires share the mature forests of maritime pine (Pinus pinaster) as the Reference state of the ecosystem. But the assessment of losses of ecosystem properties and services due to degradation has been conducted at two contrasted time scales: at the very short term on a repeatedly burned site (Várzea) and at the long term on a community without significant recovery of the overstory layer (Ayora). The restoration potential has also been assessed through rather different approaches: by actions carried out within the first year (Várzea) or 23 years after the fire (Ayora).

Várzea

The reference state in Várzea is represented by a forest of maritime pine (Pinus pinaster) where no wildfire has occurred since 1975. At the opposite extreme, the degraded areas suffered four wildfires occurred since 1975, the last one in 2012. A third situation was represented by areas that burned twice (1985 and 2012) and where burned trees were removed after the last fire by two contrasting methods: standard or traditional logging in which all wood was removed from the site, and conservation logging, in which logging residues were left on the ground organized in piles. Both logging activities were conducted during the first year after the fire and implied the cutting of all burned trees.

The experimental setup was conditioned by land availability of the burned area. Three spatially replicated plots of ca. 1000 m² were established in the reference mature pine forest (> 40 years old), in the 4-times burned (last fire in 2012) and in the standard logging areas, while three smaller plots were selected under the conservation logging treatment.

As the number of blocks was different in the reference and conservation logging sites (3) in relation to the degraded and traditional logging sites (1), we randonmly selected transects (plant cover and LFA – Landscape Function Analysis) and subplots for biomass assessment (aboveground and litter; see »Measurement of ecosystem properties and the potential for their restoration) to balance the data. In the case of the conservation logging, plots were differentiated by piles (accumulation of woody residues), inter-piles (lines between piles) and roads (paths or tracks for logging machinery). Sampling was proportionally conducted on these three contrasted spatial situations.

Results highlights

The composition of the plant community of areas subjected to Traditional and, especially, Conservation logging is closer to the Reference than the Degraded areas
The disposal of plant remains on the soil surface after wood removal increased the cover and size of patches and, hence, the conservation of resources
However, plant remains on soil might hamper the recruitment of some species, especially seeders, with direct consequences of diversity indexes and biomass build up
Ecosystem functioning assessed as LFA’s stability, infiltration and nutrient cycling indexes were improved by the restoration approaches but are still far from the natural forest
In general, restoration actions improved ecosystem properties and services at the very short term after their implementation although the dynamics of the plant communities were slowdown, probably due to the impact of the heavy machinery on the earliest regenerated plants

For more details see »Várzea Portugal: Restoration potential for preventing and reversing regime shifts

Ayora

The Reference ecosystem is a mature pine forest of Pinus pinaster and P. halepensis that was traditionally managed for different uses. The degraded ecosystem is an old and dense shrubland where pines did not recover after a wildfire in 1979. This >30 years shrubland bears a very high risk of fire as it accumulates large amounts of standing and ground fine, dead fuel. In 2003, restoration actions were carried out with the main objective of reducing fire risk. These actions included selective clearing of fire-prone shrub species and planting seedlings of more resilient resprouter species.

Three spatially replicated plots were established under three states of the ecosystem and followed the evaluation protocol used in all sites.

Results highlights

The degraded state represents an ‘old’ shrubland where gorse disappeared by natural senescence and was dominated by rosemary
The bigger size of patches in the restored areas can be related to the collapse of old shrubs in the degraded plots resulting in openings in the continuous shrubland
Biodiversity was the most improved service by restoration actions
But also the restoration approach considered in Ayora, with the reduction of levels of understory biomass, improves the ecosystem service ‘fire risk reduction’ even ten years after the application of treatments

For more details see »Ayora, Spain: Restoration potential for preventing and reversing regime shifts

Grazing Driven Landscapes

Grazing is the major degradation pressure in three out of six CASCADE field sites. From those, Messara and Randi share many landscape characteristics, physical features and land use histories while Castelsaraceno shows clear specificities. The three sites represent a good example of the most important environmental and socio-economic features of their respective regions.

Castelsaraceno

The vegetation cover for the study site shows that broad-leaved forest is the most representative land cover and only a small part of the land is devoted to agriculture. After 2000, and due to rural exodus, a large part of the territory is covered by natural grassland and broad-leaved forest. Land cover under transition is noteworthy and there has been progressive woods and shrublands encroachment on former pastures. The target Reference ecosystem is a productive pastureland with a sustainable grazing pressure composed by annuals and, in a lesser extent, perennial grasses, and where shrubs disappeared because livestock farming is widespread. Since 1991, the land has been unevenly grazed resulting in over- and undergrazed zones depending on the stocking rate supported.

Two different restoration approaches have been considered in Castelsaraceno in relation to the different grazing pressures. For the undergrazed situation, where shrubs were colonizing, the restoration action was a selective clearing of vegetation 10 years before the ecosystem assessment was made. When overgrazing was the degradation driver, fencing (8-15 years before the assessment) to avoid animals was the restoration measure considered.

The experimental setup in Castelsaraceno included three spatially replicated blocks, Monte Alpi, Favino and Piano del Campi. We have identified Reference, Overgrazed, Undergrazed, Fenced and Cleared ecosystems in all of them and three replicated plots were established for each block x pressure combination (15 plots).

Results highlights

Different restoration approaches were considered depending on the sense of the grazing pressure: Fencing in case of overgrazing, and clearing woody vegetation in case of undergrazing.
The degradation due to overgrazing seems more pronounced than that due to undergrazing. The losses of services provided in relation to the reference productive grasslands in the overgrazed are higher than in the undergrazed.
Ten years after the application of restoration, the ecosystem services evaluated in this study have been slightly improved.
Biodiversity is the most improved service associated to the two restoration approaches.
In the areas affected by overgrazing, restoration did not achieve the overall balance of services provided by the references while in the undergrazed areas the restoration through clearing showed the highest balance of services.
Provisioning services associated to grazing should be specifically considered in Castelsaraceno and integrate them into the final analysis.

For more details see »Castelsaraceno, Italy: Restoration potential for preventing and reversing regime shifts

Messara

The natural landscape in Messara is dominated by the evergreen maquis/phrygana and the main driver of pressure to these reference ecosystems is grazing. Many marginal areas under natural vegetation were cleared in the past and planted with olives. Widespread olive production in steep hilly areas in combination with grazing has triggered desertification processes. In addition, further land abandonment led to less productive lands susceptible to degradation and at the same time grazing pressure significantly increased (more than 200% increases in sheep and goats between 1980 and 1990).

In addition to the Reference and Degraded ecosystems, we selected an intermediate state of pressure defined as Semi-Degraded. It was difficult to find areas subjected to any restoration action in the past in Messara. However, we found two areas where carob trees orchards were established on overgrazed areas: Melidochori and Odigitria. In Melidochori (Figure 4), restoration works started in 1998 and two years old carob tree (Ceratonia siliqua) seedlings were planted in 2000 in a 6 x 6 m grid with maintenance actions (irrigation, fertilization and replanting dead individuals) for the first three years after planting. Grazing was excluded for ten years. LFA assessment was conducted 14 years after the establishment of the actions. Carob trees in Odigitria (Figure 5) were established by the homonymous monastery about 7 years before the assessment and irrigation was conducted during the first two years after planting. No other maintenance actions were considered. In contrast to the Melidochori site, grazing is not controlled in Odigitria.

Three replicated plots were established in the Reference, Degraded and Semi-Degraded states but one of the Semi-Degraded plots was completely affected by a fire in summer 2013 before the field assessment and only two plots were left. Only one plot was established in the two Restored areas.

" data-placement="top" data-content=" Figure 4. Restored area in Melidochori site" title="">

" data-placement="top" data-content=" Figure 5. Restored area in Odigitria site" title="">

Results highlights

The lack of areas with similar biophysical properties and land use histories that underwent any kind of restoration action in the past impeded to fully apply the ecosystem service protocol
The two restoration plots found included the transformation of overgrazed areas to carob tree orchards
Contrary to expected, interpatch cover and size were enhanced in the restored areas but the cover of bare soil was reduced as compared to the overgrazed degraded areas
The Melidochori approach significantly improved the infiltration index from the degraded lands while the Odigitria restoration enhanced the nutrient cycling
Plant cover, diversity and biomass data are needed to fully calculate regulating ecosystem services.

For more details see »Messara, Grete: Restoration potential for preventing and reversing regime shifts

Randi Forest

The natural landscape is the result of human activities and is dominated by shrublands, the typical Mediterranean phrygana, with open areas with shrubs and sparse carob and olive trees. The three studied states of the ecosystem in Randi, Degraded, Reference and Restored areas, used to be pine forest 100 years ago. After the allowance to local people to cut the pine forest and use them for firewood, only shrubs and olive trees were grown in the area but the land is not suitable for agriculture anymore and it is used for grazing, in particular goats and sheep. In the decade of 1950 goat and sheep farms were established in the area and started grazing the areas around the farms. The Restored areas (Figure 6) are far from the farms but were grazed at different intensities depending on the distance to the shelters. Animals were excluded 20 years ago from these areas but continued to graze in the degraded and on the borders of the restored areas.

{tip
Figure 6. Restored area in Randi Forest field site.} {/tip}

Three replicated plots were established in the Restored areas and the assessment protocol used in all sites was completely and strictly applied in all of them.

Results highlights

Restoration by long-term grazing exclusion increased plant cover, litter accumulation and aboveground biomass to similar levels found in the undisturbed reference areas
Plant composition and spatial structure of vegetation (cover and size of patches and interpatches) also reflected differences in the three ecosystem states
Ecosystem functioning, mainly nutrient cycling and infiltration, is sharply improved in the restored areas but are still far to the values observed in the references
The five ecosystem services calculated did not show differences between the Restored and the Reference areas and were significantly improved form the Degraded lands
Restoration in Randi can be considered as successful with the approach followed in the project

For more details see: »Randi Forest, Cyprus: Restoration potential for preventing and reversing regime shifts

Multifactor Driven Landscapes

Albatera

In this site, degradation of natural shrubland areas has resulted from a complex interplay of multiple drivers (some of them are no longer active), especially past over-exploitation of resources (overgrazing, mining, multiple cycles of marginal agriculture and land abandonment, and fire-wood gathering), in combination with harsh climate conditions. However, there are some scattered healthy shrubland areas that have been subjected to low past pressures and remain in a reasonably good shape. These areas represent the Reference state of the ecosystem. This site holds two different scenarios for the assessment of restoration actions, differing in both the implementation time and in the technologies and species used:

Old (traditional) Restoration. Implemented over the 1970s and 1980s, and consisting on a plantation of only one tree species, Pinus halepensis (Aleppo pine), on large afforestation bench terraces (Figure 7). A number of pine forest patches scattered on terraced slopes with varying degradation degree have resulted from this action.
New (ecotechnological) Restoration. In 2003 – 2004, a demonstration restoration project was performed by the Regional Forest Administration on one small catchment (24 ha) in the Albatera range area. The project counted on the scientific advice of CEAM and the Department of Ecology of the University of Alicante and it was designed to specifically combat degradation of drylands. The restoration action was performed combining several field techniques and plant species through spatially heterogeneous plantations, to better address the characteristic high heterogeneity of dryland landscapes (Chirino et al., 2009; Figure 8).

" data-placement="top" data-content=" Figure 7. Old reforestation in degraded terraces" title="">

" data-placement="top" data-content=" Figure 8a. Degraded water pipe channel" title="">

" data-placement="top" data-content=" Figure 8b. Degraded water pipe channel several years after the New restoration" title="">

Three replicated plots were established in the two alternative restoration approaches and the common assessment protocol was completely applied in all them except litter accumulation and root biomass.

Results highlights

Old restoration especially affected the contributions of sink and source areas to the landscape and their morphology
New restoration especially affected biodiversity and vegetation structure and biomass
The extremely harsh conditions in Albatera determine low recovery rates of ecosystem structure and function after restoration
New restoration improved ecosystem services in higher extent than old restoration in Albatera
At the medium and long term after restoration, ecosystem services are still far from those provided by natural undisturbed ecosystems

For more details see »Albatera, Spain: Restoration potential for preventing and reversing regime shifts

Note: For full references to papers quoted in this article see

» References

Comparison between restoration potential of study sites

2017-03-27T13:00:42+00:00

Authors:	Alejandro Valdecantos (CEAM),V. Ramón Vallejo (UB), Susana Bautista (UA), Matthijs Boeschoten (UU), Michalakis Christoforou (CUT), Ioannis N. Daliakopoulos (TUC), Oscar González-Pelayo (UAVR), Lorena Guixot (UA), J. Jacob Keizer (UAVR), Ioanna Panagea (TUC), Gianni Quaranta (UNIBAS), Rosana Salvia (UNIBAS), Víctor Santana (UAVR), Dimitris Tsaltas (CUT), Ioannis K. Tsanis (TUC)
Editor:	Jane Brandt
Source document:	Valdecantos, A. et al. (2016) Report on the restoration potential for preventing and reversing regime shifts. CASCADE Project Deliverable 5.2 104 pp

Results highlights

Overall, our results suggest that the relationship between restoration potential and degradation level matches a non-linear model, being positive until certain threshold in the loss of services, beyond which the benefits of restoration drop sharply. From the management perspective, the implications of these results are of paramount importance for prioritizing restoration efforts and assessing the cost-benefit of restoration as a function of degradation.

The large heterogeneity of target ecosystems, properties, constraints and conditions of the six field sites resulted in a very wide range of values of the variables evaluated (Table 1). For instance, plant cover percentage ran from less than 40% in the degraded state of Albatera to above 95% in the fenced sites of Castelsaraceno. Similar disparities of data are found in diversity, productivity, patch size and distribution, and functionality indexes.

" data-placement="top" data-content=" Table 1. Direct comparison of ecosystem properties between the Degraded and the Restored (the best one in case of two alternatives) states of the ecosystem in the six CASCADE field sites. " title="">

Fire-driven landscapes

We cannot do a generalization of either the impacts or the restoration potential of the two sites of the projects subjected to fire. Although Várzea and Ayora shared the reference ecosystem (pine forest), the restoration approaches and timing of application after fire are not comparable.

Várzea

In Várzea, traditional (salvage) logging resulted in better results than conservation logging in the short term, but extremely far from the reference forest. Natural pine forests show marked differences even with successfully restored forests. For instance, it has been shown that diversity and natural recruitment is significantly lower in restored pine forests than in undisturbed ones, especially under medium to low values of annual rainfall (Ruiz-Benito et al., 2012). These restored habitats also need additional restoration management such as thinning high density stands and increasing diversity through planting. In our case, the assessment of ecosystem properties and services has been carried out two years after the logging treatments were applied. This time frame is very short to detect any significant improvement. Both logging treatments showed reductions in biomass and plant cover in relation to the degraded areas (four times burned) probably related to the use of heavy machinery during the logging procedures. However, the stability, infiltration and nutrient indexes were improved in both restored sites in relation to the degraded.

Traditional logging in Várzea is a common practice in burned forests that, in Mediterranean ecosystems, has been justified to reduce further reforestation costs. However, Leverkus et al. (2012) observed that from an economic point of view a treatment similar to the conservation logging carried out in Várzea may release higher reforestation success than traditional logging with lower costs. Leverkus et al. (2014) reported lower plant species number, diversity and cover at the short-term (two years after treatment establishment) in post-fire salvage logged areas than in unmanaged burned sites or areas where wood debris were left on the ground in the SE of the Iberian Peninsula). Both logging treatments produce a homogenization of the landscape, higher in the traditional logging sites, while degraded areas without any post-fire intervention present higher heterogeneity in microclimatic conditions caused by burned plants that affect heterogeneity of resource distribution (Castro et al., 2011). In addition, salvage logging might decrease the vigor and growth of regenerating pine seedlings due to an increase of water stress, and a reduction of nutrient availability and microclimatic heterogeneity associated to standing dead wood (Moya et al., 2015), as well as increase the susceptibility of alien species to spread within the burned and salvage logged area (Moreira et al., 2013). The naturally regenerated pine seedlings in areas subjected to salvage logging usually show at the medium term lower ecophysiological performance, growth and cone production than those where more conservative logging practices were conducted (Marañón-Jiménez et al., 2013). The extraction of burned wood soon after fire may result in longer-term reductions of C sequestration than if wood had remained to decomposed in situ (Johnson et al., 2005). However, the net effect of salvage logging depends on the serotinity level of the stand (de las Heras et al. 2012). In general, post-fire emergency rehabilitation actions should be applied only to burned pine forests showing high erosion and runoff risk, with slow natural plant recovery rate Vallejo et al. (2012). These observations together with the data we recorded suggest that management activities soon after fire in Várzea may release negative net effects. On the other hand, the creation of piles of at least 50 cm height with the remains of the wood (branches and non-profitable logs), as in the conservation logging carried out in Várzea, enhances the abundance of seed dispersal bird species, especially in winter, and also richness breeding bird species, rodents, and mammals (Rost et al., 2010). Bautista et al. (2004) made some technical recommendations about the management of burned wood after fire. They included the avoidance of salvage logging in vulnerable soils until a protective vegetation cover develops, to keep some individuals as perches for birds nesting and seed dispersal, to conduct logging in patches promoting spatial heterogeneity, and to leave branches, trunks or chipped material on the ground to protect against erosion.

The unexpected better results of the traditional than the conservation logging in many ecosystem properties and services are due to the increase in patch size and cover in the former. This may lead to misunderstanding as patches in the two logging sites are not completely vegetated while interpatches are not exclusively bare soil but brush chip remains. More time is needed to assess whether the traditional and conservation logging treatments affect differently to the recovery of ecosystem properties in Várzea.

At the short term after the fire, passive restoration, e.g. by assisting natural germination or resprouting, is rather preferred than active restoration, e.g. by planting seedlings, due to the high costs and unpredictable results of the latter (Vallejo et al. 2012).

Ayora

In Ayora, restoration was conducted 23 years after the fire, when a mature shrubland was established and with the main objective of reducing fire hazard and improve vegetation resilience. The assessment was done eleven years after the application of selective clearing and plantation of resprouter seedlings. In this case, restoration at the medium term had positive impacts on most ecosystem properties and services, especially on biodiversity. Both the direct introduction of species that had locally disappeared and the increase of landscape heterogeneity by selective clearing might have promoted the significant improvement of biodiversity indexes in the restored plots. It has been observed that a thick and continuous understory layer reduces plant diversity (Royo and Carson, 2006). All other ecosystem services also improved except C sequestration as the restoration treatments included the removal of seeder fire-prone vegetation and hence the aboveground biomass. However, this fact fulfilled one of the objectives pursued by restoration as it is the reduction of the fire risk. The degraded shrubland presented two times higher amount of standing dead biomass than the restored plots. Reduction of fire hazard has been recognized as a regulating ecosystem service (Bagdon et al., 2016). The approach done to Fire Risk Reduction revealed a significant increase of this service in the Restored areas as compared to the Degraded and even to the Reference state of the ecosystem. The fuel model of the degraded community changed to less flammable types in the restored areas, probably from model 4 to 5. This is especially interesting as the reduction of fire hazard, together with increasing the resilience of the plant community, was the main objective of the restoration carried out. We have confirmed that fire risk was still reduced ten years after the application of the vegetation management treatments. In Ayora, shrublands are quite effective in protecting the soil, show high ecosystem attributes and, when resprouters are abundant, show high resilience (Vallejo et al., 2006). However and due to different reasons mainly related to stakeholders perception, restoring the forest that has been lost might be desirable.

Grazing-driven landscapes

Castelsaraceno and Randi Forest

In relation to grazing, Castelsaraceno (overgrazed) and Randi included similar restoration approaches based on grazing exclusion. In the two sites, general improvement of ecosystem properties and services were observed, especially related to enhancing biodiversity. In fact, grazing exclusion 20 years ago in Randi showed the greatest improvement in all the evaluated variables of all the field sites and ecosystem states (Table 1, Figure 1). Fenced in Castelsaraceno also improved all variables except interpatch length and litter accumulation. Changes in land use, like grazing exclusion as restoration measure, produce a trade-off between provisioning and regulating ecosystem services (Foley et al., 2005). Rong et al. (2014) reported an increase in vegetation cover, height and biomass both of the grass and shrub layers as well as in soil surface properties eight years after grazing was excluded from an arid continental region in China. However, these authors did not find significant differences in any diversity index between the degraded and the restored sites. But the effects of grazing exclusion in improving ecosystem properties are not immediate and straightforward. Li et al. (2012) observed the maximum effect of this practice on plant cover, diversity, biomass, and soil physical and chemical properties in areas with 13 and 26 years of enclosure. Passive restoration actions, such as fencing overgrazed areas or clearing shrub encroached sites, probably do not pursue a well-defined target ecosystem but alternative meta-stable states (Cortina et al., 2006).

On the other hand, and in areas where shrub encroachment is relevant like in Castelsaraceno undergrazed areas, the removal of woody vegetation by clearing may release both positive and negative effects on C sequestration in the soil depending on the precipitation regime of the site. Thus, Alberti et al. (2011) proposed that below 900 mm yr-¹ of rainfall, soil C increases with clearing woody vegetation while above this threshold (corresponding to Castelsaraceno field site) the net effect of clearing on soil C sequestration is negative. Although we did not evaluate soil C, cleared areas in Castelsaraceno showed higher root biomass but less litter accumulation than undergrazed areas.

Significant changes in the composition of plant communities have been found according to the grazing pressure (overgrazed-reference-fenced and also undergrazed-reference-cleared in Castelsaraceno). The reduction of the relative abundance of unpalatable species in degraded areas or its replacement by other more palatable at the medium term after grazing exclusion has been previously reported in other Mediterranean drylands (Jeddi and Chaieb, 2010) as well as the modification of the relative proportion of different life-forms (Medina-Roldán et al., 2012). These changes in plant community composition are less pronounced in the most arid areas and increase both with precipitation and net primary productivity (Milchunas and Lauenroth, 1993). But not only composition is sensitive to grazing exclusion. Several studies reported an increase in diversity indexes such as those we have evaluated in the project (species richness, Shannon-Wiener’s and evenness indexes) after ca 10 years of excluding grazing (Jeddi and Chaieb, 2010; Wang et al., 2016). However, it has also been observed that species composition does not significantly change at moderate levels of grazing at the time that both regulating and provisioning ecosystem services are optimized (Oñatibia et al., 2015). These authors and others (e.g. Medina-Roldán et al. 2012) observed a reduction of C and N stocks in heavily grazed arid rangelands as compared to moderate grazed areas, and recommend a reduction of grazing pressure for increasing C sequestration rather that complete grazing exclusion. Probably, the definition of optimum intermediate stocking rates instead of complete grazing exclusion is a main objective for the management of these areas where grazing represents an important ecosystem service (Papanastasis et al., 2015).

Messara

The case of Messara is rather different than the other sites affected by grazing. The restoration did not aim to recover the pre-disturbance or reference state of the ecosystem but a transformation of land use from grazing to carob tree orchards as a silvopastoral or agroforestry system. Carob trees are a landmark of Greek landscapes as it is one of the greatest producers of carob pods (5.600 ha and 22.000 tons of pods in 2013; data from FAO), most of the production is concentrated in Crete. The reference, semi-degraded and degraded states in Messara represent different situations along the degradation trajectory while the restored options built alternative system through replacement following Bradshaw’s classical structure-function model (Bradshaw 1984). Under this situation, the assessment based on the spatial arrangement of vegetation, the contribution of patches and interpatches to the landscape, and the evaluation of soil surface properties provides useful insights of ecosystem properties but does not represent a reliable approach of the restoration potential of ecosystem services of these degraded sites. The incorporation of plant cover and plant biomass will surely result in significant improvements of the ecosystem services included in this report. The possibility of getting external funds from the EU Common Agricultural Policy for this agroforestry transformation, as happened in Melidochori, is another aspect to be considered in the final balance of the impacts of this land management alternative. In addition, provisioning services such as fodder or gum products (Papanastasis 1989) can be provided by this transformation from overgrazed areas to carob tree orchards when physical features of the site, especially soil depth, are appropriate.

Multifactor-driven landscapes

Albatera

In the field site with the highest aridity index, Albatera, there was an important improvement of ecosystem services and properties due to the development of new restoration technologies, such as higher number of planted species, species selection based on geomorphological features, compost application or water harvesting structures (Chirino et al., 2009). However, despite both the new and the traditional restoration improved the state of the degraded ecosystem, its properties are still far from the values of the undisturbed reference sites. One of the reasons underlying the better performance of the planted seedlings in the new than in the old restoration approach is that it included the optimization of hydrological properties that have significant effect on restoration success (Urgeghe and Bautista, 2015). It is important to highlight that the new restoration action in Albatera was applied only ten years before the assessment, and even so it already yielded much better results than the traditional approach implemented several decades ago. We expect that the positive effects of this management option will increase over time as ecological processes act at slow rate in these extremely stressed sites (Pugnaire et al., 2006).

Conclusions

Our analytical approach to evaluate the potential to restore areas impacted by fire, grazing or multiple simultaneous stresses has provided useful insights on constraints and opportunities for restoration that may be considered when designing landscape management options. Our assessment is based on biophysical features in the different states of the ecosystem and special weight relies on Landscape Function Analysis. Other services that has not been quantified in this report such as the reduction of fire risk in Várzea or the provisioning services especially in Castelsaraceno could also be considered to better capture the net outcome of restoration actions.

Stakeholders perception about ecosystem services and properties should be incorporated in the decision making (Bullock et al. 2011).

" data-placement="top" data-content=" Figure 1. Summary of the changes of standardized ecosystem services due to restoration actions in all CASCADE field sites . Bars represent an average of all five environmental services evaluated." title="">

" data-placement="top" data-content=" Figure 2. Recovery of ecosystem services by restoration (Z values in Restored plots) in relation to their losses by degradation (Z value Reference – Z value Degraded). The best restoration approach has been selected in the field sites with two alternatives. 1: Castelsaraceno Undergrazed; 2: Ayora; 3: Castelsaraceno Overgrazed; 4: Várzea; 5: Randi; 6: Albatera (red dot)." title="">

The study sites represent different degradation drivers, different intensities and duration of pressures, and different climatic, water stress and soil vulnerablity to degradation of representative Mediterranean landscapes. However, the contrast between reference and degraded sites, and between patch and interpatch characteristics constitute an ecologically-sound common indicator of degradation severity. Restoration measures also yielded different outcomes, e.g. different degree of change in ecosystem properties and services. Different restoration treatments and evaluation times after application, and the diverse nature of restoration trechniques applied are factors that modulated restoration results. Despite this variation, when the degree of ecosystem change achieved by restoration (relative to degraded states) is analyzed as a function of the relative impact of degradation (relative to the reference state), we observed a global positive relationship between them (Figure 2), so that the more intense the loss of services the higher the effects of restoration on the recovery of those services. However, one of the sites, Albatera, does not follow this pattern. The stressful conditions in Albatera site (the highest aridity index) determine the slow recovery of ecosystem dynamics and properties even in case of successful restoration practices. Furthermore, despite the multiple degradation factors that drove the ecosystem to its degraded state ceased many decades ago, Albatera did not ever show any sign of self-recovery towards healthier conditions, which indicates that the pressures exerted in the past triggered the shift of the system to a particularly severe degraded alternative state that has proven to be rather stable.

Note: For full references to papers quoted in this article see

» References

References

2017-01-26T12:48:08+00:00

Authors:	Alejandro Valdecantos (CEAM),V. Ramón Vallejo (UB), Susana Bautista (UA), Matthijs Boeschoten (UU), Michalakis Christoforou (CUT), Ioannis N. Daliakopoulos (TUC), Oscar González-Pelayo (UAVR), Lorena Guixot (UA), J. Jacob Keizer (UAVR), Ioanna Panagea (TUC), Gianni Quaranta (UNIBAS), Rosana Salvia (UNIBAS), Víctor Santana (UAVR), Dimitris Tsaltas (CUT), Ioannis K. Tsanis (TUC)
Editor:	Jane Brandt
Source document:	Valdecantos, A. et al. (2016) Report on the restoration potential for preventing and reversing regime shifts. CASCADE Project Deliverable 5.2 104 pp

References cited in articles in this section of CASCADiS

Alberti, G., Leronni, V., Piazzi, M., Petrella, F., Mairota, P., Peressotti, A., Piussi, P., Valentini, R., Gristina, L., Mantia, T.L., Novara, A., Rühl, J., 2011. Impact of woody encroachment on soil organic carbon and nitrogen in abandoned agricultural lands along a rainfall gradient in Italy. Reg. Environ. Chang. 11, 917–924. doi:10.1007/s10113-011-0229-6
Alkemade, R., Bakkenes, M., Eickhout, B., 2011. Towards a general relationship between climate change and biodiversity: an example for plant species in Europe. Reg. Environ. Chang. 11, 143-150. doi: 10.1007/s10113-010-0161-1
Archer, S.R., Predick, K.I., 2014. An ecosystem services perspective on brush management: Research priorities for competing land-use objectives. J. Ecol. 102, 1394–1407. doi:10.1111/1365-2745.12314
Baeza, M.J., Raventós, J., Escarré, A., Vallejo, V.R., 2003. The effect of shrub clearing on the control of the fire-prone species Ulex parviflorus. For. Ecol. Manage. 186, 47–59. doi:10.1016/S0378-1127(03)00237-8
Baeza, M.J., Vallejo, V.R., 2008. Vegetation recovery after fuel management in Mediterranean shrublands. Appl. Veg. Sci. 11, 151–158. doi:10.3170/2007-7-18339
Bagdon, B.A., Huang, C.-H., Dewhurst, S., 2016. Managing for ecosystem services in northern Arizona ponderosa pine forests using a novel simulation-to-optimization methodology. Ecol. Modell. 324, 11–27. doi:10.1016/j.ecolmodel.2015.12.012
Bautista, S., Gimeno, T., Mayor, A.G., Gallego, D., 2004. El tratamiento de la madera quemada tras los incendios forestales. En: Vallejo, V.R., Alloza, J.A. (eds.) Avances en el estudio de la gestión del monte Mediterráneo, pp. 547-570. Fundación CEAM, Valencia
Bautista, S., Lamb, D., 2013. Ecosystem services. Encyclopedia of Environmental Management. DOI: 10.1081/E-EEM-120046612
Bautista, S., Mayor, A.G., 2010. Ground-based methods and indicators for the assessment of desertification prevention and restoration actions. In: Deliverable D2.1 Working papers on Assessment Methods – PRACTICE Project.
Bradshaw, A.D., 1984. Ecological principles and land reclamation practice. Landscape planning, 11, 35-48.
Bullock, J.M., Aronson, J., Newton, A.C., Pywell, R.F., Rey-Benayas, J.M., 2011. Restoration of ecosystem services and biodiversity: conflicts and opportunities. Trends in Ecology & Evolution, 26, 541-549.
Castro, J., Allen, C.D., Molina-Morales, M., Marañón-Jiménez, S., Sánchez-Miranda, Á., Zamora, R., 2011. Salvage logging versus the use of burnt wood as a nurse object to promote post-fire tree seedling establishment. Restor. Ecol. 19, 537–544. doi:10.1111/j.1526-100X.2009.00619.x
Chirino, E., Vilagrosa, A., Cortina, J., Valdecantos, A., Fuentes, D., Trubat, R., Luis, V.C., Puértolas, J., Bautista, S., Peñuelas, J.L., Vallejo, V.R., 2009. Ecological restoration in degraded drylands: the need to improve the seedling quality and site conditions in the field, in: Forest Management. Nova Science Publ., New York, USA, pp. 85–158.
Cortina, J., Maestre, F.T., Vallejo, R., Baeza, M.J., Valdecantos, A., Pérez-Devesa, M., 2006. Ecosystem structure, function, and restoration success: Are they related? J. Nat. Conserv. 14, 152–160. doi:10.1016/j.jnc.2006.04.004
Daliakopoulos, I., Tsanis, I., 2013. Historical evolution of dryland ecosystems. CASCADE report series D2.1. 122 pp.
De Groot, R.S., Wilson, M.A., Boumans, R.M.J., 2002. A typology for the classification, description and valuation of ecosystem functions, goods and services. Ecol. Econ. 41, 393–408.
de las Heras, J., Moya, D., Vega, J.A., Daskalakou, E., Vallejo, V.R., Grigoriadis, N., Tsitsoni, T., Baeza, J., Valdecantos, A., Fernández, C., Espelta, J., Fernandes, P., 2012. Post-fire management of serotinous pine forests. In Post-Fire Management and Restoration of Southern European Forests (pp. 121-150). Springer Netherlands.
Foley, J. a, Defries, R., Asner, G.P., Barford, C., Bonan, G., Carpenter, S.R., Chapin, F.S., Coe, M.T., Daily, G.C., Gibbs, H.K., Helkowski, J.H., Holloway, T., Howard, E. a, Kucharik, C.J., Monfreda, C., Patz, J. a, Prentice, I.C., Ramankutty, N., Snyder, P.K., 2005. Global consequences of land use. Science 309, 570–4. doi:10.1126/science.1111772
Hilderbrand, R.H., Watts, A.C., Randle, A.M., 2005. The myths of restoration ecology. Ecol. Soc. 10. doi:19
Hooper, D.U., Chapin III, F.S., Ewel, J.J., Hector, A., Inchausti, P., Lavorel, S., Lawton, J.H., Lodge, D.M., Loreau, M., Naeem, S., Schmidt, B., Setala, H., Symstad, A.J., Vandermeer, J., Wardle, D.A., 2005. Effects of biodiversity on ecosystem functioning: a consensus of current knowledge. Ecol. Monogr. 75, 3–35. doi:10.1890/04-0922
Jeddi, K., Chaieb, M., 2010. Changes in soil properties and vegetation following livestock grazing exclusion in degraded arid environments of South Tunisia. Flora Morphol. Distrib. Funct. Ecol. Plants 205, 184–189. doi:10.1016/j.flora.2009.03.002
Johnson, D.W., Murphy, J.F., Susfalk, R.B., Caldwell, T.G., Miller, W.W., Walker, R.F., Powers, R.F., 2005. The effects of wildfire, salvage logging, and post-fire N-fixation on the nutrient budgets of a Sierran forest. For. Ecol. Manage. 220, 155–165. doi:10.1016/j.foreco.2005.08.011
Lammerant, J., Peters, R., Snethlage, M., Delbaere, B., Dickie, I., Whiteley, G., 2013. Implementation of 2020 EU Biodiversity Strategy: Priorities for the restoration of ecosystems and their services in the EU. Report to the European Commission. ARCADIS (in cooperation with ECNC and Eftec). http://ec.europa.eu/environment/nature/biodiversity/comm2006/pdf/2020/RPF.pdf (Accessed 11/04/2016).
Lavelle, P., Dugdale, R., Scholes, R., Asefaw Behere, A., Carpenter, E., Izac, A.M., Karl, D., Lemoalle, J., Luizao, F., Scholes, M., Tréguer, P., Ward, B., 2005. Nutrient cycling. Chapter 12 in: Millennium Ecosystem Assessment, Island Press, Washington, DC.
Leverkus, A.B., Lorite, J., Navarro, F.B., Sánchez-Cañete, E.P., Castro, J., 2014. Post-fire salvage logging alters species composition and reduces cover, richness, and diversity in Mediterranean plant communities. J. Environ. Manage. 133, 323–331. doi:10.1016/j.jenvman.2013.12.014
Leverkus, A.B., Puerta-Piñero, C., Guzmán-Álvarez, J.R., Navarro, J., Castro, J., 2012. Post-fire salvage logging increases restoration costs in a Mediterranean mountain ecosystem. New For. 43, 601–613. doi:10.1007/s11056-012-9327-7
Li, Y., Zhao, X., Chen, Y., Luo, Y., Wang, S., 2012. Effects of grazing exclusion on carbon sequestration and the associated vegetation and soil characteristics at a semi-arid desertified sandy site in inner Mongolia, northern China. Can. J. Soil Sci. 92, 807–819. doi:10.4141/CJSS2012-030
Lindig-Cisneros, R., Desmond, J., Boyer, K.E., Zedler, J.B., 2003. Wetland restoration thresholds: Can a degradation transition be reversed with increased effort? Ecol. Appl. 13, 193–205. doi:10.1890/1051-0761(2003)013[0193:WRTCAD]2.0.CO;2
MA (Millenium Ecosystem Assessment). 2005. MA Conceptual Framework. Chapter 1 in Millennium Ecosystem Assessment. Island Press, Washington, DC
Maestre, F.T., Cortina, J., Vallejo, R., 2006. Are ecosystem composition, structure, and functional status related to restoration success? A test from semiarid mediterranean steppes. Restor. Ecol. 14, 258–266. doi:10.1111/j.1526-100X.2006.00128.x
Marañón-Jiménez, S., Castro, J., Querejeta, J.I., Fernández-Ondoño, E., Allen, C.D., 2013. Post-fire wood management alters water stress, growth, and performance of pine regeneration in a Mediterranean ecosystem. For. Ecol. Manage. 308, 231–239. doi:10.1016/j.foreco.2013.07.009
Medina-Roldán, E., Paz-Ferreiro, J., Bardgett, R.D., 2012. Grazing exclusion affects soil and plant communities, but has no impact on soil carbon storage in an upland grassland. Agric. Ecosyst. Environ. 149, 118–123. doi:10.1016/j.agee.2011.12.012
Milchunas, D.G., Lauenroth, W.K., 1993. Quantitative effects of grazing on vegetation and soils over a global range of environments. Ecol. Monogr. 63, 327–366.
Moreira, F., Ferreira, A., Abrantes, N., Catry, F., Fernandes, P., Roxo, L., Keizer, J.J., Silva, J., 2013. Occurrence of native and exotic invasive trees in burned pine and eucalypt plantations: Implications for post-fire forest conversion. Ecol. Eng. 58, 296–302. doi:10.1016/j.ecoleng.2013.07.014
Moya, D., De las Heras, J., López-Serrano, F., Ferrandis, P., 2015. Post-fire seedling recruitment and morpho-ecophysiological responses to induced drought and salvage logging in Pinus halepensis Mill. stands. Forests 6, 1858–1877. doi:10.3390/f6061858
Oñatibia, G.R., Aguiar, M.R., Semmartin, M., 2015. Are there any trade-offs between forage provision and the ecosystem service of C and N storage in arid rangelands? Ecol. Eng. 77, 26–32. doi:10.1016/j.ecoleng.2015.01.009
Papanastasis, V.P., 1989. Multipurpose woody plants for the Mediterranean arid zone of Greece. Programme de recherche Agrimed.
Papanastasis, V.P., Bautista, S., Chouvardas, D., Mantzanas, K., Papadimitriou, M., Mayor, A.G., Koukioumi, P., Papaioannou, A., Vallejo, R. V., 2015. Comparative assessment of goods and services provided by grazing regulation and reforestation in degraded Mediterranean rangelands. L. Degrad. Dev. doi:10.1002/ldr.2368
Pugnaire, F.I., Luque, M.T., Armas, C., Gutiérrez, L., 2006. Colonization processes in semi-arid Mediterranean old-fields. J. Arid Environ. 65, 591–603. doi:10.1016/j.jaridenv.2005.10.002
Rojo, L., Bautista, S., Orr, B. J., Vallejo, R., Cortina, J., Derak, M., 2012. Prevention and restoration actions to combat desertification. An integrated assessment: The PRACTICE Project. Secheresse, 23, 219-226.
Rong, Y., Yuan, F., Ma, L., 2014. Effectiveness of exclosures for restoring soils and vegetation degraded by overgrazing in the Junggar Basin, China. Grassl. Sci. 60, 118–124. doi:10.1111/grs.12048
Rost, J., Clavero, M., Bas, J.M., Pons, P., 2010. Building wood debris piles benefits avian seed dispersers in burned and logged Mediterranean pine forests. For. Ecol. Manage. 260, 79–86. doi:10.1016/j.foreco.2010.04.003
Royo, A.A., Carson, W.P., 2006. On the formation of dense understory layers in forests worldwide: consequences and implications for forest dynamics, biodiversity, and succession. Can. J. For. Res. 36, 1345–1362. doi:10.1139/x06-025
Ruiz-Benito, P., Gómez-Aparicio, L., Zavala, M. a., 2012. Large-scale assessment of regeneration and diversity in Mediterranean planted pine forests along ecological gradients. Divers. Distrib. 18, 1092–1106. doi:10.1111/j.1472-4642.2012.00901.x
Su, H., Liu, W., Xu, H., Wang, Z., Zhang, H., Hu, H., Li, Y., 2015. Long-term livestock exclusion facilitates native woody plant encroachment in a sandy semiarid rangeland. Ecol. Evol. 5, 2445–2456. doi:10.1002/ece3.1531
Tongway, D.J., Hindley, N.L., 2004. Landscape function analysis manual: procedures for monitoring and assessing landscapes with special reference to minesites and rangelands. Canberra, ACT: CSIRO Sustainable Ecosystems
Urgeghe, A.M., Bautista, S., 2015. Size and connectivity of upslope runoff-source areas modulate the performance of woody plants in Mediterranean drylands. Ecohydrology 8, 1292–1303. doi:10.1002/eco.1582
Valdecantos, A., Baeza, M.J., Vallejo, V.R., 2009. Vegetation management for promoting ecosystem resilience in fire-prone mediterranean shrublands. Restor. Ecol. 17, 414–421. doi:10.1111/j.1526-100X.2008.00401.x
Valdecantos, A., Vallejo V.R., 2015. Report on structural and functional changes associated to regime shifts in Mediterranean dryland ecosystems. Deliverable 5.1 CASCADE Project (EU GA283068)
Vallejo, R., Aronson, J., Pausas, J.G., Cortina, J., 2006. Restoration of Mediterranean woodlands. Restor. Ecol. new Front. 193–207.
Vallejo, V.R., Arianoutsou, M., Moreira, F., 2012. Fire ecology and post-fire restoration approaches in Southern European forest types. In Post-Fire Management and Restoration of Southern European Forests (pp. 93-119). Springer Netherlands.
Vörösmarty, C.J., Leveque, C., Revenga, C., 2005. Fresh water. Chapter 7 in: Millennium Ecosystem Assessment. Island Press, Washington, DC.
Wang, K., Deng, L., Ren, Z., Li, J., Shangguan, Z., 2016. Grazing exclusion significantly improves grassland ecosystem C and N pools in a desert steppe of Northwest China. Catena 137, 441–448. doi:10.1016/j.catena.2015.10.018
Whisenant, S., 1999. Repairing damaged wildlands: a process-oriented, landscape-scale approach. Cambridge University Press, Port Chester, NY, USA.