One Ecosystem : Research Article
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Corresponding author: Laura Maebe (laura.maebe@uliege.be)
Academic editor: Sander Jacobs
Received: 22 Mar 2019 | Accepted: 23 May 2019 | Published: 03 Jun 2019
© 2019 Laura Maebe, Hugues Claessens, Marc Dufrêne
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation: Maebe L, Claessens H, Dufrêne M (2019) The critical role of abiotic factors and human activities in the supply of ecosystem services in the ES matrix. One Ecosystem 4: e34769. https://doi.org/10.3897/oneeco.4.e34769
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In Western Europe, ecosystems have been shaped to maximise the supply of one specific biomass provisioning ecosystem service (ES), such as food or timber, with detrimental impacts on other ES. The ES approach has therefore been established to better understand the multiple interactions between human society and ecosystems. A variety of methods have been developed to assess ES and their relationships, for instance the ES matrix model based on land cover classes. This popular, flexible and simple method allows combining different data sources and easily comparing ES. However, in general, this method poorly takes into account landscape heterogeneity while abiotic factors and human activities seem to play an important role in ES supply. The objective of this paper is twofold: (1) to extent the methodology based on the ES matrix model by including abiotic factors and human activities and (2) to test the impacts of these two types of factors on ES supply and their relationships.
The assessment focused on the capacity of the forest to supply six ES depending on six types of soil ranging from productive soils to more constraining or less productive soils (i.e. abiotic factors) and two contrasting forest management strategies (i.e. human activities). This amended ES matrix was applied on one hand, to map the supply of ES and their relationships in four municipalities in the Ardenne ecoregion (Southern Belgium) and on the other hand, to investigate the impacts of three scenarios (i.e. three different management strategies) on ES supply and their relationships.
The amended ES matrix shows large differences in ES supply between the two forest management strategies on the more constraining and less productive soils, creating differences in the spatial pattern of ES. The changes in ES supply amongst the three scenarios and the current supply were quantified to identify the best management options.
In conclusion, one particular forest is not like another in terms of ES supply and their relationships. To capture this heterogeneity, we propose an amended ES matrix including abiotic factors and human activities. The maps, based on this matrix, allow identifying the hotspots (i.e. high capacity to supply different ES) and coldspots (i.e. low capacity to supply different ES or strong trade-offs between provisioning ES and regulating/cultural ES). Forest management should be adapted to the abiotic conditions, in particular in the coldspots, to ensure a more balanced supply of ES.
Forest management, abiotic factors, land sparing versus land sharing framework, ecosystem services supply, ecosystem services relationship, ecosystem services matrix
Over time, human societies have shaped ecosystems to optimally produce the desired provisioning ecosystem services (ES), such as food or timber (
Fig.
Schematic representation of the balance between collective (i.e. regulating and cultural ES) and individual interests (i.e. provisioning ES). The managers shape the ecosystem to supply provisioning ES which benefit specific beneficiaries (i.e. individual interests). The price of these provisioning ES is determined by the market. The managers can also impact positively or negatively regulating and cultural ES and their stakeholders, respectively, termed beneficiaries and non-beneficiaries (i.e. collective interests). The governance system can influence the balance between collective and individual interests by regulation, labelling, specific aid etc. Adapted from
The assessment of ES and their relationships can help with respect to analysing the balance between collective and individual interests. However, ES assessment is not a simple exercise (
A variety of methods, such as biophysical and environmental models (e.g.
We focus on one specific ES assessment method: the ES matrix model. This two-dimensional matrix links the different land cover classes with their capacities to supply ES (
The matrix model is one of the most popular ES assessment methods (
Nevertheless, the ES matrix model also has disadvantages. First, it disregards landscape heterogeneity in the supply of ES by considering only individual land cover classes (
In response to these critics,
Specific recommendations were also discussed by
Nevertheless, the matrix model can still be improved in the integration of other determinants rather than land cover (
Schematic representation of the integrated assessment of ES. The supply of ES is determined by three main components:
Ecosystems result from the interactions between biotic and abiotic factors. The managers shape the ecosystem to maximise the supply of some ES (i.e. maximised ES) which benefit some stakeholders (i.e. transformers and consumers) and which, in turn, impact the supply of other ES (i.e. impacted ES) and other stakeholders (i.e. impacted users). The integrated assessment should consider the different ES and stakeholders to balance the collective and individual interests. Adapted from
The biotic and abiotic factors interact together to shape the ecosystem (
As illustrated in Fig.
By adding information on abiotic factors and human activities in the ES matrix, this method gives up some of its simplicity and some of its utility in data scarce situations, but it considerably improves its accuracy while still considering the landscape heterogeneity. It is true that other tools which allow systematically taking into account abiotic factors and human activities such as InVEST (Integrated Valuation of Ecosytem Services and Tradeoffs) (
To the best of our knowledge, no study has yet investigated systematically and widely both the abiotic factors and the human activities in the ES matrix. The studies have mainly considered land cover (e.g.
The main objective of this study is to improve the method based on the ES matrix by taking into account both abiotic factors and human activities. A second objective is to study the impacts of abiotic factors and human activities on ES supply and their relationships.
The assessment of ES supply and their relationships was performed based on an amended ES matrix. Two improvements were made to qualify the supply of ES from ecosystems: the inclusion of
Moreover, the guidelines provided by
This study focused on one class of land cover (i.e. forest) in order to study exclusively the influence of abiotic factors and human activities on the supply of ES and their relationships. The forest was chosen because of its particular importance in ES supply, diversity and trade-offs (
The ecological context is defined as the physical and chemical conditions of the environment mainly determined by the elevation, topography and soil according to its texture, moisture, nutrient availability etc. Six ecological contexts were differentiated:
to characterise the forest capacity to provide ES and the risk to impact them by human activities.
Human activities were considered by differentiating two contrasting forest management strategies, the two most common in Wallonia:
These two forest management strategies have been deliberately defined in a highly contrasted way to highlight the differences in ES supply. However, even if spruce forests are no longer necessarily drained, while broadleaves are sometimes cultivated in even-aged forests, these two contrasting forest management strategies correspond quite well to the actual reality of forest management in the Ardenne (Southern ecoregion of Belgium) resulting from the silvicultural choices in the 20th century.
Six ES were selected from the classification of the Walloon platform on ES (
They were chosen by considering their specific importance to the study area and their representative nature to represent the three main categories of ES (i.e. provisioning, regulating and cultural ES) and some of the main ES provided by forests (according to
The amended ES matrix links the six ES (on the x-axis) to the two forest management strategies and the six ecological contexts, in total 12 combinations (on the y-axis) (Fig.
Amended ES matrix illustrating the capacity of the different combinations of a forest management strategy with an ecological context to supply the six ES. The meaning of the code name of the six ES can be found in Table
The six ecosystem services according to the classification of the Walloon Platform on ES (Wal-ES), with their code name and their corresponding name in the CICES-BE classification (
ES category |
ES (Wal-ES) |
ES code |
ES (CICES-BE) |
Indicator |
References |
Uneven-aged broadleaved forests |
Pure even-aged spruce plantations |
Production |
Wood production |
Wood |
Plant fibres and materials |
Volume of mobilizable wood |
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Less yield and volume due to slow growth |
More yield but the volume produced is not stable over time (clear cutting) |
Regulation |
Global climate regulation by sequestration of greenhouse gases |
Carbon |
Global climate regulation by reduction of greenhouse gas concentrations |
Amount of carbon sequestered in forest vegetation (BOC) and soils (SOC) |
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BOC: less volume but larger wood density, larger volume of the tree (above- and below-ground) and more understory vegetation |
BOC: more yield but lower wood density, lower volume of tree (above- and below-ground) and almost no understory vegetation |
SOC: higher due to leaf decomposition and increasing carbon stocks on wet and peat soils |
SOC: lower despite a biomass accumulation in the first stages but clear cutting and soil drainage induces high mineralization |
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Flood protection |
Flood |
Natural flood protection & sediment regulation |
Capacity of soil infiltration and evapotranspiration of vegetation |
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Lower tree evapotranspiration and interception of rainwater (deciduous trees) but continuous presence of vegetation cover and deep rooting allowing better infiltration. No drainage and even slowdown effect of water flows in alluvial zones thanks to vegetation |
Higher tree evapotranspiration and interception of rainwater but clear cutting and the absence of understory vegetation have a negative impact. Existing huge drainage networks on wet and peat soils highly intensify floods |
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Erosion protection |
Erosion |
Buffering and attenuation of mass flows + Protection against water and wind erosion |
Soil and sediment retention capacity |
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High erosion protection in all ecological contexts thanks to deep rooting allowing better infiltration and the presence of a permanent vegetation cover especially on alluvial soils where the understory vegetation captures sediments |
Low erosion protection on all sensitive soils: steep slopes (clear cutting), wet and peat soils (drainage networks) and alluvial soils (absence of understory vegetation) |
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Water purification and oxygenation |
Water |
Water purification and oxygenation |
Denitrification and phosphorus retention capacity |
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Vegetation filters pollutants with lower effects on podzolic soils where nutrients leaching is high |
Spruce plantations increase soil acidification and have a higher N deposition. The mineralisation of the litter induced by the clear cutting is a very high source of pollutants for surface water especially, in the presence of drains or slopes |
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Cultural |
Natural areas for outdoor recreation |
Recreation |
Landscape for outdoor recreation |
Forest landscape attractivity |
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Broadleaved forests are very much more preferred to spruce plantations for their naturality, complex structure, tree diversity, lighting, colours in autumn welcoming etc., as well as the presence of surface water (in Wallonia) |
Spruce plantations are in general less popular, particularly in the presence of clear cutting and signs of intensive exploitation (e.g. ruts) (in Wallonia) |
Such scores were gathered from master student works (Master bioengineer in Nature and Forest Management, Gembloux Agro-Bio Tech, University of Liège, Belgium) over five years (2013–2017). They scored the six ES by group from a literature review (47 references) according to a single supply indicator (Table
The amended ES matrix was applied on a forest massif of four municipalities (Libin, Libramont-Chevigny, Saint-Hubert and Tellin; 50.0°N; 5.3°E) of Wallonia (Southern Belgium) in the Ardenne ecoregion. These four municipalities take part in the First Forest Charter in Wallonia, led by a local organisation (Natural Resources Development asbl), aiming at the appropriate development of the social, ecological and economic functions of the forest massif. The assessment of ES was performed as part of the diagnostic of the forest. It was followed by a territorial game (i.e. spatial representations are used by stakeholders as a tool to describe and analyse their territory and to mediate the participative process) with the stakeholders to build a shared vision of the forest and to identify actions designed to improve the multifunctionality of the forest.
The four municipalities encompass an area of 48,500 ha mostly covered by forests (54% of the area), followed by agricultural land (35%), mainly pastures due to a colder climate and poorer soils characterising the Ardenne ecoregion compared to the rest of Wallonia. Urban areas (1%) are barely present, despite a growing urbanisation mainly at the expense of agricultural land.
The majority of the forest is public (66%), primarily owned by the four municipalities (92% of the public forest). Broadleaves and conifers are equally represented. Beech and oak dominate in uneven-aged broadleaved forests. The most frequent coniferous species are in decreasing order: spruce, Douglas fir, larch and Scots pine. They are almost always planted in pure even-aged stands. Only a few stands are becoming uneven-aged due to natural regeneration.
The four municipalities have many resources such as:
The amended ES matrix shows that uneven-aged broadleaved forests have a lower capacity to provide wood than pure even-aged spruce plantations, while they have a higher capacity to supply regulating and cultural services (Fig.
The confidence of the ES scores was analysed according to
Confidence of ES scores from the literature review. Confidence is determined by agreement and evidence quality of the literature review (see
The standard deviation of the scores from the master 1 student work between 2013 and 2017 was calculated. The standard deviation of 77% of the scores is lower than 1. Only 23% of scores have a standard deviation ranging from 1 to 2.1 and it is mainly on peat and alluvial soils.
The ES scores were linked to spatial data to map ES in spatially explicit units of similar biophysical settings (i.e. a combination of a forest management strategy with an ecological context). The spatial data included a map of the forest cover (
The forest cover and sensitivity soil maps were intersected with the software Arcgis version 10.2. A new column combining the forest management strategy with the ecological context was added to the attribute table. This attribute table was joined with the amended ES matrix using this new column as a common identifier field to create a map for each of the six ES.
To analyse the relationships between ES, a synthetic map was created based on the six ES maps to represent the balance between collective and individual interests. The average score of regulating and cultural services was subtracted from the score of wood production for each polygon in Arcgis. The scale ranges from -5 = collective interests are considerably lower than individual interests; via 0 = collective and individual interests are equal; to 4 = collective interests are considerably higher than individual interests.
The influence of human activities on the supply of ES was also studied through three scenarios. These three scenarios intended to improve the supply of ES and their relationships were designed:
For the last scenario, the matrix of the scores of the ES supply provided by spruce forests was adapted to this new management through a literature review (see the references and the arguments of Table
‘Continuous cover forestry’ matrix illustrating the capacity to supply the six ES of the uneven-aged spruce forests (continuous cover forestry), depending on the ecological context. The meaning of the code name of the six ES can be found in Table
In general, each ES is well provided for the three different ecological contexts, particularly with respect to mesic brown soils. Lower scores are present for some ES:
The supply of the six ES was compared between each scenario and the current status. The area weighted difference between each scenario and the current status was calculated for each ES based on two equations (Equation 1 and Equation 2). In the first equation, only the areas affected by the scenario were considered while for the second equation, the entire forest massif was taken into account.
\(D_1 = (∑_{i=1}^{n_{Scenario}} (x_i^{Scenario}*S_i^{Scenario})-∑_{i=1}^{n_{Scenario}} (x_i^{Current status}*S_i^{Current status}))/∑_{i=1}^{n_{Scenario}} S_i^{Current status})\)
Equation 1 . Difference in capacity to supply the ES between the scenario and the current status weighted by the area concerned by the scenario.
\(D_2=(∑_{i=1}^{12}(x_i^{Scenario}*S_i^{Scenario})-∑_{i=1}^{12}(x_i^{Current status}*S_i^{Curent status})) /∑_{i=1}^{12}S_i^{Curent status} \)
Equation 2 . Difference in capacity to supply the ES between the scenario and the current status weighted by total area of the forest massif.
D1 = Area weighted difference in the capacity to supply the ES between the scenario and the current status for the areas affected by the scenario
D2 = Area weighted difference in the capacity to supply the ES between the scenario and the current status for the entire forest massif
i = Each combination of a forest management strategy with an ecological context
x = Score of the ES
S = Area (ha) covered by each combination of a forest management strategy with an ecological context
n = Number of combinations of a forest management strategy with an ecological context affected by the scenario
The data gathered from the ecotope map, the soil sensitivity soil map and the amended ES matrix are compiled in an Excel file (see https://doi.org/10.5281/zenodo.3228110). These data were used to map the six ES and the balance between collective and individual interests as well as to calculate the area weighted difference between each scenario and the current status for the case study.
The assessment of the six ES in the forest massif highlights the influence of abiotic factors and human activities on the capacity of the forest to provide ES. First, the maps of the six ES and their relationships (Fig.
Ecotopes land cover map 2015 (A), sensitivity soil map (B) and maps of wood production (C), global climate regulation by sequestration of GES (D), flood protection (E), erosion protection (F), water purification and oxygenation (G), natural areas for outdoor recreation (H) and the balance between collective and individual interests (I) of the forest massif of the four municipalities (Libin, Libramont-Chevigny, Saint-Hubert and Tellin, Ardenne, Belgium).
The forest cover is analysed, based on the ecotopes land cover map of 2015, as a proxy of forest management (Fig.
The distribution of the ecological contexts (Fig.
Alluvial soils concentrate around the three main rivers and their tributaries:
Wet soils are present upstream of these rivers, particularly in Saint-Hubert (10%), Tellin (8%) and Libramont-Chevigny (7%). Lhomme and Lesse and their tributaries create deep valleys with steep slopes, especially in Tellin (13%) and Saint-Hubert (6%). Some podzolic soils are disseminated mainly in Saint-Hubert (6%) and Libramont-Chevigny (4%). Finally, peat soils are scarcely present, apart from in Libramont-Chevigny (2%).
The repartition of the forest capacity to provide the six ES (Fig.
Global climate regulation by sequestration of GES (Fig.
Wood production (Fig.
Finally, erosion control (Fig.
The relationships amongst the six ES are examined depending on the particular forest management and the ecological context using the map representing the balance between collective (i.e. regulating and cultural ES) and individual interests (i.e. wood production) (Fig.
For each scenario, two histograms illustrating the area weighted difference in ES supply between the scenario and the current status are analysed to understand the influence of human activities (reflected in the three scenarios) on each ES. They show that the three scenarios lead overall to an increase in the capacity to supply ES (Fig.
Area weighted difference in supply of ES between the scenario ‘Restoration’ (white bar), ‘Restoration + compensation’ (light grey bar) and ‘Restoration + continuous cover forestry’ (dark grey bar) and the current status based on Equation 1 on areas affected by scenario (A) and on Equation 2 on the entire forest massif (B). The meaning of the code name of the six ES can be found in Table
The best scenario, leading overall to the highest increase in ES supply, differs from one histogram to another depending on the area considered. For the first histogram (Fig.
We made use of the ES matrix model to develop our methodology because this method has numerous advantages. It is efficient and flexible, allowing the combination of different types of data (e.g. survey, modelling, field measurement) from various sources (
We improved the original ES matrix from
Other authors also made some improvements in the original ES matrix but none of them systematically considered both abiotic factors and human activities. For example,
Our results (see Fig.
Even if the influence of the ecological context and the management is, on average, strong, it varies in intensity. For example, ES supply on alluvial soils is more variable than on mesic brown soils and is, on average, more constant for uneven-aged broadleaved forests than for pure even-aged spruce plantations.
The impacts of the ecological context and the management on ES supply interact with each other. For example, the impacts of intensive management on regulating and cultural ES are exacerbated on sensitive soils. It is thus important to consider together the ecological context and the management in the assessment of ES supply.
Even if our results cannot be generalised, due to the fact that they are only applicable at the Ardenne ecoregion, our simple and fast methodology can be applied around the world to assess the trends in the capacity of ecosystems to supply ES and their relationships, depending on abiotic factors and human activities.
Nevertheless, our methodology can still be improved: temporal aspects (e.g. seasonal effects, dynamics) could be added (
Even if the methodology can be improved further, the shortcomings were reasonable because the main point of this paper is not to make an exact ES assessment for the area but to present an easy-to-apply methodology showing ES trends and taking into account both abiotic factors and human activities.
The maps (Fig.
Maps are a useful tool in ES assessment. In contrast to the ES matrix, they highlight the variation in the abiotic conditions and human activities in the landscape explaining the variable distribution of ES scores (Burkhard et al. 2009). Moreover, they allow us to identify key areas: hotspots (i.e. high capacity to supply ES) and coldspots (i.e. low capacity to supply different ES or strong trade-offs between provisioning ES and regulating/cultural ES), where ES supply can be improved, as demonstrated by
For the case study, each of the three scenarios leads overall to an improvement in ES supply (Fig.
The test of other scenarios can bring new insights. For example, a scenario with mixed broadleaved and coniferous forests could be studied to determine how they can complement one another. Natural open habitats could be included in a scenario to compare their ES supply to forest habitats.
As the ecological context determines the impacts of the forest management on ES supply and their relationships, forest management should be adapted to the ecological context. The land-sharing versus land-sparing framework looks promising to better balance collective and individual interests (
Position of each combination of a forest management strategy with an ecological context along the gradient of land sparing for conservation (collective interests: regulating and cultural ES) to land sharing (balance between collective and individual interests) to land sparing for production (individual interests: provisioning ES) for the current status, the three scenarios and the functional zoning. The percentage of surface covered by each combination is provided.
This framework can be combined with functional zoning to minimise as much as possible the trade-offs between ES while maintaining wood production. This approach of functional management divides the forest into three zones:
It has several advantages:
Three functional zones can be proposed in the studied forest massif:
The transformation of spruce forests into uneven-aged broadleaved forests on sensitive soils also makes sense for biodiversity. The potential habitats of most of the ecological contexts (97% of the forest massif) are included in the list of the protected habitats of the European Commission (Natura 2000 network) and three of them are priority habitats (Table
Natural forest and open habitat for each ecological context under Natura 2000.
* Priority habitats.
Ecological context |
Natural forest habitat (Natura 2000 code) |
Natural open habitat |
Mesic brown soil |
Acidophilous beech forest (9110) |
Dry heath (4030) |
Steep slope |
Forest of slopes, screes and ravines (9180*) + Acidophilous beech forest (9110) |
Upland siliceous scree (8150) |
Alluvial soil |
Riparian alluvial forest (91E0*) |
Alluvial meadow (6430) |
Wet soil |
Old acidophilous oak wood (9190) |
Wet heath (4010) |
Peat soil |
Bog woodland (91D0*) |
Degraded raised bog (7120*) |
Nevertheless, to implement this proposition on the ground, it should be reviewed with relevant stakeholders to determine what is socially preferable (
An easy-to-apply methodology, based on the ES matrix model, was developed to assess ES supply and their relationships based on abiotic factors and human activities. This methodology capitalises on the advantages of the ES matrix model (e.g. efficient, flexible, combination of several data sources, mapping possible, easy comparison between ES), whilst minimising its disadvantages. On one hand, the inclusion of abiotic factors and human activities in the ES matrix allows capturing part of the landscape heterogeneity. On the other hand, the combination of various data sources reduces the uncertainties while the quantification of the errors and the detailed description of the methodology make them transparent. Nevertheless, this methodology can be developed further, notably by specifying the biotic factors (e.g. composition and structure of the forest) and by including the temporal dimension. Finally, the scores of the ES matrix should be updated to new insights obtained from literature.
This amended ES matrix showed that one particular forest is not like another in terms of ES supply: depending on its management and the ecological context, it provides different sets of ES at different levels. This heterogeneity is important in terms of mapping in order to identify the hotspots and coldspots in ES supply. This ES mapping could be an efficient tool to increase awareness amongst the stakeholders on the diversity of ES and their relationships, as well as on the influence of abiotic factors and human activities on ES supply. Forest management plans should be adjusted to the heterogeneity in ES supply to ensure the best balance between collective and individual interests. In this way, they should be adapted to the ecological context by a functional zoning approach which combines land sparing and land sharing. These management propositions should be investigated further to integrate societal preferences, existing constraints and their spatial and temporal cross-scaled effects.
This study was part of the First Forest Charter in Wallonia, led by Natural Resources Development asbl.