Conserving biodiversity and ecosystem services

Mapping Peer-Reviewed Scientific Studies on Plant Trait–Service Linkages Across Ecosystems: A Bibliometric Analysis

The concept of ‘ecosystem service’ has gained momentum in the twenty-first century to bridge the gap between human–nature interactions. However, the challenge remains to map the flow of ecosystem services (ES) for their efficient management. Among the multiple existing methods, biophysical assessments provide better knowledge of the state of the ecosystem and its mapping for complimentary services. Trait–service linkage is one of the tools to reliably link biodiversity with ES if we better understand the role functional traits play in the underlying ecosystem processes. In this paper, we have performed a bibliometric analysis of published literature on ES and plant functional traits to identify the current state of knowledge on trait–service linkage, biases, research gaps, and challenges. There was a skewed geographical basis for trait–service linkage studies; most studies were conducted in Europe and North America. The majority of the research focused on supporting and regulating ES, mainly carbon sequestration, biomass production, and climate regulation, using a particular set of vegetative traits, such as leaf, root, and plant height, and ignored most regeneration traits, except for a few flower traits. A matrix to quantify the association between ES and selected plant traits (specific leaf area, leaf dry matter content, leaf area, leaf nitrogen content, vegetation height, wood density, canopy density, root length, root density, flowering time, flower color and flower size) revealed that the two leaf traits (specific leaf area and leaf dry matter content) in the linkage have contrasting associations with multiple ES. The study illustrated that there is still a considerable research gap in linking plant traits with essential ES (biomass production, climate and water regulation). Thus, suggest future studies on ES should focus more on trait–service linkage across major ecosystems to underpin key ecosystem processes for better sustenance of ES and human well-being.

Mussel parasite richness and risk of extinction

Parasite conservation is important for the maintenance of ecosystem diversity and function. Conserving parasites relies first on understanding parasite biodiversity and second on estimating the extinction risk to that biodiversity. Although steps have been taken independently in both these areas, previous studies have overwhelmingly focused on helminths in vertebrate hosts over broad scales, providing low resolution and excluding a large proportion of possible host and parasite diversity. We estimated both total obligate parasite richness and parasite extinction risk in freshwater mussels (Unionidae and Margaritiferidae) from Europe and the United States to provide a case study for considering parasite conservation in a severely understudied system. We used currently reported host-parasite relationships to extrapolate parasite diversity to all possible mussel hosts and then used the threat levels of those hosts to estimate the extinction risk for both described and undescribed parasites. An estimated 67% of parasite richness in freshwater mussels is undescribed and over 80% of the most host-specific groups (digenean trematodes and ciliates) are undescribed. We estimated that 21% of this total parasite fauna is at immediate risk of extinction, corresponding to 60 unique species, many of which will likely go extinct before being described. Given the important roles parasites play in community structure and function and the strong ecosystem engineering capacities of freshwater mussels, such extinctions are likely to severely affect freshwater ecosystems. Our detailed study of mussel parasites provides compelling evidence for the hidden conservation threat to parasites through extinction cascades and shows parasites are deserving of immediate attention.

Comparison between Demand and Supply of Some Ecosystem Services in National Parks: A Spatial Analysis Conducted Using Italian Case Studies

In recent decades, modeling approaches of ecosystem services (ES) have been used extensively at the international level, providing useful tools during the decision-making process by integrating both physical and economic information, thus improving its management. The relationship between supply and demand may impact social welfare: for example, a deficit in ES could negatively influence demand (either potential or effective). For this reason, the relational study between supply and demand is necessary for the sustainable management of natural resources; particularly since the demand for some ES must be fulfilled not only on a local scale but also globally (as in the case of regulatory ES). This paper proposes an ES analysis framework that links the flow of services (supply) generated by the interaction between natural, human and social capital with consumption (demand) connected to potential beneficiaries. Specifically, we analyze three ES: Forage production, regulation of local climate (PM10), and carbon sequestration in three national parks (Aspromonte National Park, Circeo National Park, and Appennino Tosco Emiliano National Park). The use of synthetic (biophysical) indicators, on a spatial basis, made it possible to quantify the supply and demand of specific catchments with the aim of accounting for the surplus/deficit through the calculation of the ES supply and demand ratio (ESDR). In fact, sustainable land management requires a balance between supply and demand in relation to the different needs of the stakeholders and local community. The relationship between supply and demand of ES can help identify resource use trade-offs, thus rendering the achievement of management and protection objectives more efficient. Lastly, through the use of monetary coefficients, it was possible to calculate the benefits of increasing the awareness of public decision-makers of ES’s value and the importance of implementing integrated strategies for environmental protection and enhancement.

A blessing for the Yangtze River: optimization of Chinese regional policy planning for water yield and purification in the Three Gorges Reservoir Area

Land use/land cover (LULC) changes impact the structure and functioning of ecosystems, which consequently influences the provisioning of a range of ecosystem services (ES). There is a growing consensus regarding the merit of integrating the evaluation of ES into regional policy planning. The Yangtze River is the world's third longest and supports more than 6% of its population. However, assessing the potential impacts of different resource management policies upon ES is complicated in the Yangtze basin. To remedy this, here we designed a scenario analysis-based approach that used remotely sensed data and GIS (geographic information system) to analyze the relationships between ES (i.e., water flow regulation, water purification) and policies envisioned to improve human welfare in the Chongqing municipality, in the upper reaches of the Three Gorges Reservoir Area (TGRA) in the Yangtze basin. This watershed area has high population density and suffers from severe flood hazard and critical pollution issues. The GEOMOD modeling technique was used to predict LULC changes according to policy planning alternatives, producing scenarios by 2050 for the TGRA watershed. The GIS-based ES model (InVEST model) was developed as a tool to inform the decision-making process with the intention of aligning conservation measures with economic development. We examine policy effectiveness by comparing three scenarios for 2050: scenario-1 maintains the current policy, with no considerations of ES; scenario-2 integrates ES into policy planning; and scenario-3 integrates ES into policy planning considering the needs of local people. Our scenario-based LULC change analysis showed that the land with large increases in water flow regulation (i.e., values ≤-3000 × 10³ m³ km^-2) were scattered over the entire study area, while phosphorus reduction (i.e., values ≤ -30 kg km^-2) were located mainly along rivers in all scenarios. Scenario-2 and scenario-3 are based on policies aiming at enhancing ES provisioning; for these, the projected ecological risks of water pollution are significantly reduced (39.97% and 37.58%, respectively). Total net changes of the investigated ES under scenario-2 or scenario-3 were almost double that occurring under scenario-1. Although scenario-2 and scenario-3 showed a near-equal total net change, water purification under scenario-2 was the greatest relative to forest expansion. However, scenario-3 offered the best future environmental development scenario, as it accounted for the demand and supply characteristics of water yield and purification in different regions. The water purification service made the greatest contribution to positive and negative effects (26%-47% and -7%, respectively) on ES provisioning. Linking water purification service to policy planning would effectively improve the overall ES. These scenario forecasting results will help the Three Gorges Dam to gain more ecological benefits via improvements to water flow regulation and the effective alleviation of degraded water quality in heavily populated regions in the Yangtze basin.

Representation of biodiversity and ecosystem services in East Africa's protected area network

The dramatic increase in anthropogenic activity severely threatens the biodiversity and life-support services that underpin human well-being. The broadened focus of protecting ecosystem services (ESs) better aligns the interests of people and biodiversity conservation. In this study, we used species richness as a surrogate for biodiversity and mapped the key ESs in East Africa with the goal to assess the spatial congruence between biodiversity and ESs, and evaluate the representation of current protected areas (PAs) network for biodiversity and ESs. The results showed that PAs well represented for species richness and regulating services but underrepresented for provisioning services. The PAs network occupies 10.96% of East Africa's land surface, and captures 20.62-26.37% of conservation priorities for vertebrate and plant species. It encompasses more than 16.23% of priority areas for three regulating services, but only 6.17% and 5.22% for crop and livestock production, respectively. Strong correlations and high overlaps exist between species richness and regulating services, particularly for carbon storage, water yield and plants. Thus, we believe that actions taken to conserve biodiversity also will protect certain ESs, which in turn will create new incentives and funding sources for the conservation of biodiversity. Overall, our results have wide-ranging policy implications and can be used to optimize conservation strategies for both biodiversity and multiple ESs in East Africa.

Spatial and Temporal Monitoring of Pasture Ecological Quality: Sentinel-2-Based Estimation of Crude Protein and Neutral Detergent Fiber Contents

Frequent, region-wide monitoring of changes in pasture quality due to human disturbances or climatic conditions is impossible by field measurements or traditional ecological surveying methods. Remote sensing imagery offers distinctive advantages for monitoring spatial and temporal patterns. The chemical parameters that are widely used as indicators of ecological quality are crude protein (CP) content and neutral detergent fiber (NDF) content. In this study, we investigated the relationship between CP, NDF, and reflectance in the visible–near-infrared–shortwave infrared (VIS–NIR–SWIR) spectral range, using field, laboratory measurements, and satellite imagery (Sentinel-2). Statistical models were developed using different calibration and validation data sample sets: (1) a mix of laboratory and field measurements (e.g., fresh and dry vegetation) and (2) random selection. In addition, we used three vegetation indices (Normalized Difference Vegetative Index (NDVI), Soil-adjusted Vegetation Index (SAVI) and Wide Dynamic Range Vegetation Index (WDRVI)) as proxies to CP and NDF estimation. The best models found for predicting CP and NDF contents were based on reflectance measurements (R2 = 0.71, RMSEP = 2.1% for CP; and R2 = 0.78, RMSEP = 5.5% for NDF). These models contained fresh and dry vegetation samples in calibration and validation data sets. Random sample selection in a model generated similar accuracy estimations. Our results also indicate that vegetation indices provide poor accuracy. Eight Sentinel-2 images (December 2015–April 2017) were examined in order to better understand the variability of vegetation quality over spatial and temporal scales. The spatial and temporal patterns of CP and NDF contents exhibit strong seasonal dependence, influenced by climatological (precipitation) and topographical (northern vs. southern hillslopes) conditions. The total CP/NDF content increases/decrease (respectively) from December to March, when the concentrations reach their maximum/minimum values, followed by a decline/incline that begins in April, reaching minimum values in July.

Designing a network of green infrastructure to enhance the conservation value of protected areas and maintain ecosystem services

There is a growing demand for holistic landscape planning to enhance sustainable use of ecosystem services (ESS) and maintenance of the biodiversity that supports them. In this context, the EU is developing policy to regulate the maintenance of ESS and enhance connectivity among protected areas (PAs). This is known as the network of Green Infrastructure (GI). However, there is not a working framework defined to plan the spatial design of such network of GI. Here, we use the software Marxan with Zones, to prioritize the spatial distribution of different management zones that accommodate the needs of a network of GI. These zones included a conservation zone, mainly devoted to protecting biodiversity, a GI zone, that aimed at connecting PAs and maintaining regulating and cultural ESS; and a management zone devoted to exploiting provisioning ESS. We performed four planning scenarios that distribute the targets for ESS and biodiversity in different ways across management zones. We also conducted a sensitivity analysis by increasing ESS targets to explore trade-offs that may occur when managing together biodiversity and ESS. We use Catalonia (northeastern Spain) as a case study. We found that the representation of ESS could be achieved for intermediate targets in all scenarios. There was, however, a threshold on these targets over which trade-offs appeared between maintaining regulating and cultural ESS and biodiversity versus getting access to provisioning ESS. These "thresholds values" were displaced towards higher ESS targets when we moved from more strict to more flexible planning scenarios (i.e., scenarios that allowed mixing representation of objectives for biodiversity and ESS within the same zone). This methodological approach could help design a framework to integrate biodiversity and ESS management in holistic plans and decision making and, at the same time, meeting European mandates concerning the design of GI networks, or similar needs elsewhere.

What Is Left for Our Next Generation? Integrating Ecosystem Services into Regional Policy Planning in the Three Gorges Reservoir Area of China

Land use/Land cover (LULC) changes as a result of policy planning influence ecosystem structures, processes, and functions, which are the basis for providing a wide range of ecosystem services (ES). There is an increasing consensus about the importance of integrating ES into ecological policy but quantifying the potential impacts of different policy on ES has proven difficult. We designed a remote sensing, geographic information system and scenario analysis-based approach to estimate and analyze the relationship between ES (soil conservation and carbon sequestration) and ecological policy designed to improve human welfare in the Chongqing municipality in the upper reaches of the Three Gorges Reservoir Area, China; a densely populated, highly modified watershed with serious soil erosion and flood hazard. Three alternative scenarios in 2050 were modeled for the Three Gorges Reservoir Area watershed. The model GEOMOD was used to predict future LULC changes due to policy planning. The ES models (Universal Soil Loss Equation model and Carnegie-Ames-Stanford Approach model) were designed to inform decisions, with an aim to align economic forces with conservation. We examine policy effectiveness by comparing scenarios for 2050 (Scenario1: Maintain current policy with no considerations of ES; Scenario2: Integrate ES into policy planning; Scenario3: Integrate ES into policy planning in view of the need of local people). Scenario-based LULC change analysis revealed that if the current afforestation policy continues (scenario 1), total ES would be further increased in 2050 due to expansion of forest cover. However, by targeting policy to improve ES provision (scenarios 2 and 3), ecological risks of soil loss can be significantly reduced and carbon sequestration enhanced. Scenario 3, thus, provided the best future environmental development scenario considering the need of local people in each region for ES. This scenario will theoretically help the Three Gorges Dam to harvest more ecological benefits through improvements in soil conservation and carbon sequestration. This study highlights the observation that including ES in policy planning and has a great potential to generate opportunities to maximize ES. This study highlights that including ES in policy planning has a great potential to generate opportunities to maximize ES. Hence, there is a need to encourage proper implementation of ecological policy to maintain and improve ES.

Sustainable Land-use Management Under Biodiversity Lag Effects

The destruction of natural habitats for agricultural production results in local biodiversity loss. Biodiversity loss in turn affects agricultural production indirectly through a range of biodiversity-dependent ecosystem services. Land conversion thus results in a negative externality, mediated by changes in biodiversity. When the consequences of this externality are delayed in time, lack of internalization results in overshoot-and-collapse dynamics, which are undesirable from a sustainability perspective. Here, we emphasize the importance of forward-looking policies for the long-term sustainability of human-nature interactions. We show that the internalization of this externality through a land tax can result in several win-win effects in the long run. First, more biodiversity is preserved at equilibrium, which increases the carrying capacity and total well-being of the human population. Second, a taxation path that maximizes the discounted sum of human utilities prevents or greatly alleviates overshoot-and-collapse crises, thus increasing the sustainability of the system. In particular, this result holds in the case of imperfect information regarding the precise temporal dynamics of biodiversity loss, suggesting that the design of efficient land-use management policies is possible despite incomplete ecological data. This study highlights the need to internalize biodiversity-dependent externalities through economic incentives, especially under uncertainty regarding long-term ecological dynamics.

A review of regulation ecosystem services and disservices from faunal populations and potential impacts of agriculturalisation on their provision, globally

Land use and cover change (LUCC) is the main cause of natural ecosystem degradation and biodiversity loss and can cause a decrease in ecosystem service provision. Animal populations are providers of some key regulation services: pollination, pest and disease control and seed dispersal, the so-called faunal ecosystem services (FES). Here we aim to give an overview on the current and future status of regulation FES in response to change from original habitat to agricultural land globally. FES are much more tightly linked to wildlife populations and biodiversity than are most ecosystem services, whose determinants are largely climatic and related to vegetation structure. Degradation of ecosystems by land use change thus has much more potential to affect FES. In this scoping review, we summarise the main findings showing the importance of animal populations as FES providers and as a source of ecosystem disservices; underlying causes of agriculturalisation impacts on FES and the potential condition of FES under future LUCC in relation to the expected demand for FES globally. Overall, studies support a positive relationship between FES provision and animal species richness and abundance. Agriculturalisation has negative effects on FES providers due to landscape homogenisation, habitat fragmentation and loss, microclimatic changes and development of population imbalance, causing species and population losses of key fauna, reducing services whilst enhancing disservices. Since evidence suggests an increase in FES demand worldwide is required to support increased farming, it is imperative to improve the understanding of agriculturalisation on FES supply and distribution. Spatial conservation prioritisation must factor in faunal ecosystem functions as the most biodiversity-relevant of all ecosystem services and that which most closely links sites of service provision of conservation value with nearby sites of service use to provide ecosystem services of agricultural and economic value.

Identification, Prioritization and Mapping of Ecosystem Services in the Panchase Mountain Ecological Region of Western Nepal

Ecosystem services (ES) are critical to human well-being, especially in developing countries. Improved understanding of the status of ES is required to help people improve their quality of life. The status of ES is largely unknown in many regions of Nepal. This study was carried out in one of Nepal’s biodiversity hotspots, the Panchase Mountain Ecological region (PMER), to identify, prioritize and map the major ES in the region. Primary data for the study were collected through key informant interviews, focus group discussions, a transect walk, and field observations. Similarly, secondary data were obtained from published and unpublished reports and satellite images of the study area. The data were analyzed both qualitatively and quantitatively. Thirty-seven ES were identified from the study landscape. Among them, nine were provisioning services, thirteen regulating services, nine cultural services, and six supporting services. Interestingly, the prioritization of ES among stakeholders differed on the basis of their background, particular features of their landscape, professional engagement, and individual interests. For instance, forest users prioritized provisioning services for their daily needs whereas forest managers prioritized regulating and cultural services for overall ecosystem management and aesthetic values. Mapping of the ES from the landscape for 1995 and 2015 identified that forest area and associated ES have likely increased, especially in the upland regions, while agricultural land and their associated ES have decreased. The study can be used as a reference by planners and policy makers in managing ES in the PMER to increase synergies and reduce trade-off among various services.

Combining ecosystem services assessment with structured decision making to support ecological restoration planning

Accounting for ecosystem services in environmental decision making is an emerging research topic. Modern frameworks for ecosystem services assessment emphasize evaluating the social benefits of ecosystems, in terms of who benefits and by how much, to aid in comparing multiple courses of action. Structured methods that use decision analytic-approaches are emerging for the practice of ecological restoration. In this article, we combine ecosystem services assessment with structured decision making to estimate and evaluate measures of the potential benefits of ecological restoration with a case study in the Woonasquatucket River watershed, Rhode Island, USA. We partnered with a local watershed management organization to analyze dozens of candidate wetland restoration sites for their abilities to supply five ecosystem services-flood water retention, scenic landscapes, learning opportunities, recreational opportunities, and birds. We developed 22 benefit indicators related to the ecosystem services as well as indicators for social equity and reliability that benefits will sustain in the future. We applied conceptual modeling and spatial analysis to estimate indicator values for each candidate restoration site. Lastly, we developed a decision support tool to score and aggregate the values for the organization to screen the restoration sites. Results show that restoration sites in urban areas can provide greater social benefits than sites in less urban areas. Our research approach is general and can be used to investigate other restoration planning studies that perform ecosystem services assessment and fit into a decision-making process.

Spatio-temporal variations of conservation hotspots based on ecosystem services in Xishuangbanna, Southwest China

Integrating biodiversity and ecosystem services (BES) has been viewed as an appropriate approach to identifying conservation priorities. Taking Xishuangbanna tropical region in Southwest China, different BESs (habitat quality [used as a proxy for biodiversity], carbon storage, and water yield) were quantified using the InVEST model and conservation hotspots from 1976, 1990, and 2010 were identified by overlapping and ranking the service layers. Results showed that BESs areas were unevenly distributed. High habitat quality and carbon storage areas located in the eastern part of the region were mainly occupied by broad-leaved forest, while high water yield areas were covered by grassland and tropical forests. Recognized hotspots were primarily composed of the broad-leaved forest and shrub grassland. However, these habitat types declined by nearly 50% from 1.25×10⁵ ha to 0.63×10⁵ ha and became more fragmented during the study period. We also found that the sub-watersheds which decreased in BES had fewer hotspots distributed and suffered greater landscape fragmentation. Our study further explored the impacts of land-use conversion on BES, and illustrated the necessity and feasibility of BESs in identifying potential conservation areas.

To what extent can ecosystem services motivate protecting biodiversity?

Society increasingly focuses on managing nature for the services it provides people rather than for the existence of particular species. How much biodiversity protection would result from this modified focus? Although biodiversity contributes to ecosystem services, the details of which species are critical, and whether they will go functionally extinct in the future, are fraught with uncertainty. Explicitly considering this uncertainty, we develop an analytical framework to determine how much biodiversity protection would arise solely from optimising net value from an ecosystem service. Using stochastic dynamic programming, we find that protecting a threshold number of species is optimal, and uncertainty surrounding how biodiversity produces services makes it optimal to protect more species than are presumed critical. We define conditions under which the economically optimal protection strategy is to protect all species, no species, and cases in between. We show how the optimal number of species to protect depends upon different relationships between species and services, including considering multiple services. Our analysis provides simple criteria to evaluate when managing for particular ecosystem services could warrant protecting all species, given uncertainty. Evaluating this criterion with empirical estimates from different ecosystems suggests that optimising some services will be more likely to protect most species than others.

Species richness alone does not predict cultural ecosystem service value

Many biodiversity-ecosystem services studies omit cultural ecosystem services (CES) or use species richness as a proxy and assume that more species confer greater CES value. We studied wildflower viewing, a key biodiversity-based CES in amenity-based landscapes, in Southern Appalachian Mountain forests and asked (i) How do aesthetic preferences for wildflower communities vary with components of biodiversity, including species richness?; (ii) How do aesthetic preferences for wildflower communities vary across psychographic groups?; and (iii) How well does species richness perform as an indicator of CES value compared with revealed social preferences for wildflower communities? Public forest visitors (n = 293) were surveyed during the summer of 2015 and asked to choose among images of wildflower communities in which flower species richness, flower abundance, species evenness, color diversity, and presence of charismatic species had been digitally manipulated. Aesthetic preferences among images were unrelated to species richness but increased with more abundant flowers, greater species evenness, and greater color diversity. Aesthetic preferences were consistent across psychographic groups and unaffected by knowledge of local flora or value placed on wildflower viewing. When actual wildflower communities (n = 54) were ranked based on empirically measured flower species richness or wildflower viewing utility based on multinomial logit models of revealed preferences, rankings were broadly similar. However, designation of hotspots (CES values above the median) based on species richness alone missed 27% of wildflower viewing utility hotspots. Thus, conservation priorities for sustaining CES should incorporate social preferences and consider multiple dimensions of biodiversity that underpin CES supply.

Delivery of crop pollination services is an insufficient argument for wild pollinator conservation

There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is restricted to a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting wild bee communities are dominated by a small number of common species, and threatened species are rarely observed on crops. Dominant crop pollinators persist under agricultural expansion and many are easily enhanced by simple conservation measures, suggesting that cost-effective management strategies to promote crop pollination should target a different set of species than management strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires more than just ecosystem-service-based arguments.

One argument for conserving biological diversity is that it delivers beneficial ecosystem services. However, Kleijn et al. show that the economic benefits of crop pollination are delivered by only a small subset of relatively common species, arguing that threatened species should be considered separately.

Selecting cost-effective areas for restoration of ecosystem services

Selection of areas for restoration should be based on cost-effectiveness analysis to attain the maximum benefit with a limited budget and overcome the traditional ad hoc allocation of funds for restoration projects. Restoration projects need to be planned on the basis of ecological knowledge and economic and social constraints. We devised a novel approach for selecting cost-effective areas for restoration on the basis of biodiversity and potential provision of 3 ecosystem services: carbon storage, water depuration, and coastal protection. We used Marxan, a spatial prioritization tool, to balance the provision of ecosystem services against the cost of restoration. We tested this approach in a mangrove ecosystem in the Caribbean. Our approach efficiently selected restoration areas that at low cost were compatible with biodiversity targets and that maximized the provision of one or more ecosystem services. Choosing areas for restoration of mangroves on the basis carbon storage potential, largely guaranteed the restoration of biodiversity and other ecosystem services.

Temporal-spatial changes in ecosystem services and implications for the conservation of alpine rangelands on the Qinghai-Tibetan Plateau

Ecosystem services emerged as a concept to bridge ecosystem conservation and the sustainable use of natural resources. Given the limited funding and resources available for ecosystem conservation, fully understanding and identifying the temporal-spatial patterns of ecosystem services can help establish a cost-efficient ecosystem conservation strategy. Although studies have indicated globally important ecosystem services on the Qinghai-Tibetan Plateau (QTP), key ecosystem services, such as carbon storage, water provision and habitat quality, have not been spatial-explicitly quantified, leading to a lack of understanding of key spatial patterns for conservation of this unique alpine ecosystem. To fill this gap, these three key ecosystem services were simulated for the QTP rangelands by using the Integrated Valuation of Ecosystem Services and Trade-off model, and the hotspots of those ecosystem services were evaluated and identified. It was shown that alpine meadows played a key role compared with alpine steppe and alpine desert in providing the ecosystem services of water provision, carbon storage and habitat quality in the alpine rangelands of the QTP. In addition, it was shown that there had been a considerable decrease in both the potential and the protected hotspots of ecosystem service between 1990 and 2000, implying that the existing conservation system (i.e. National Nature Reserves) could not effectively maintain these hotspots and that there was a need to restore those degraded rangeland ecosystems within the existing conservation system. The large-scale spatial heterogeneity among the different ecosystem services found in this study can be used to inform a more comprehensive conservation strategy for the provision of ecosystem services as well as biodiversity in the QTP rangelands.

Impact of microbial diversity depletion on xenobiotic degradation by sewage-activated sludge

Microbial diversity is generally considered as having no effect on the major processes of the ecosystem such as respiration or nutrient assimilation. However, information about the impact of diversity on minor functions such as xenobiotic degradation is scant. We studied the role of diversity on the capacity of an activated-sludge microbial community to eliminate phenanthrene, a polycyclic aromatic hydrocarbon. We also assessed the impact of diversity erosion on the ability of activated sludge to oxidize a wide range of organic compounds. The diversity of activated sludge was artificially modified by dilution to extinction followed by regrowth stage which led to communities with similar biomass but displaying a diversity gradient. The capacity of activated-sludge community to degrade phenanthrene was greatly modified: at high levels of diversity, the community was able to mineralize phenanthrene whereas at medium levels it first of all partially lost its ability to mineralize this pollutant and at the lowest diversity, the activated sludge completely lost its capacity to transform phenanthrene. Diversity depletion also reduced the metabolic diversity and biomass productivity of sewage-activated sludge. This study demonstrates that diversity erosion can greatly affect major ecosystem services such as pollutant removal.

Modeling soil conservation, water conservation and their tradeoffs: a case study in Beijing

Natural ecosystems provide society with important goods and services. With the rapid increase in human populations and excessive utilization of natural resources, humans frequently enhance the production of some services at the expense of the others. Although the need for tradeoffs between conservation and development is urgent, the lack of efficient methods to assess such tradeoffs has impeded progress. Three land use strategy scenarios (development scenario, plan trend scenario and conservation scenario) were created to forecast potential changes in ecosystem services from 2007 to 2050 in Beijing, China. GIS-based techniques were used to map spatial and temporal distribution and changes in ecosystem services for each scenario. The provision of ecosystem services differed spatially, with significant changes being associated with different scenarios. Scenario analysis of water yield (as average annual yield) and soil retention (as retention rate per unit area) for the period 2007 to 2050 indicated that the highest values for these parameters were predicted for the forest habitat under all three scenarios. Annual yield/retention of forest, shrub, and grassland ranked the highest in the conservation scenario. Total water yield and soil retention increased in the conservation scenario and declined dramatically in the other two scenarios, especially the development scenario. The conservation scenario was the optimal land use strategy, resulting in the highest soil retention and water yield. Our study suggests that the evaluation and visualization of ecosystem services can effectively assist in understanding the tradeoffs between conservation and development. Results of this study have implications for planning and monitoring future management of natural capital and ecosystem services, which can be integrated into land use decision-making.

Ecosystem service provision: an operational way for marine biodiversity conservation and management

Since no extensive conceptual framework has been developed on the issues of ecosystem service (ES) and service provider (SP) in the marine environment, we have made an attempt to apply these to the conservation and management of marine biodiversity. Within this context, an accurate individuation of SPs, namely the biological component of a given ecosystem that supports human activities is fundamental. SPs are the agents responsible for making the ES-based approach operational. The application of these concepts to the marine environment should be based on an model different to the terrestrial one. In the latter, the basic model envisages a matrix of a human-altered landscape with fragments of original biodiversity; conversely, in the marine environment the model provides fragments where human activities are carried out and the matrix is represented by the original biodiversity. We have identified three main classes of ES provision: in natural, disturbed and human-controlled environments. Economic valuation of marine ESs is an essential condition for making conservation strategies financially sustainable, as it may stimulate the perceived need for investing in protection and exploitation of marine resources.

Increased dependence of humans on ecosystem services and biodiversity

Humans have altered ecosystems more rapidly and extensively than ever, largely to meet rapidly growing demands for resources along with economic development. These demands have been considered important drivers of ecosystem degradation and biodiversity loss. Are humans becoming less dependent on ecosystem services and biodiversity following economic development? Here, we used roundwood production, hydroelectricity generation and tourism investment in 92 biodiversity hotspot and 60 non-hotspot countries as cases to seek the answer. In 1980–2005, annual growth rates of roundwood production, hydroelectricity generation and tourism investment were higher in hotspot countries (5.2, 9.1 and 7.5%) than in non-hotspot countries (3.4, 5.9 and 5.6%), when GDP grew more rapidly in hotspot countries than non-hotspot countries. Annual growth rates of per capita hydropower and per capita tourism investment were higher in hotspot countries (5.3% and 6.1%) than in non-hotspot countries (3.5% and 4.3%); however, the annual growth rate of per capita roundwood production in hotspot countries (1%) was lower than in non-hotspot countries (1.4%). The dependence of humans on cultural services has increased more rapidly than on regulating services, while the dependence on provisioning services has reduced. This pattern is projected to continue during 2005–2020. Our preliminary results show that economic growth has actually made humans more dependent upon ecosystem services and biodiversity. As a consequence, the policies and implementations of both economic development and ecosystems/biodiversity conservation should be formulated and carried out in the context of the increased dependence of humans on ecosystem services along with economic development.

Safeguarding biodiversity and ecosystem services in the Little Karoo, South Africa

Global declines in biodiversity and the widespread degradation of ecosystem services have led to urgent calls to safeguard both. Responses to this urgency include calls to integrate the needs of ecosystem services and biodiversity into the design of conservation interventions. The benefits of such integration are purported to include improvements in the justification and resources available for these interventions. Nevertheless, additional costs and potential trade-offs remain poorly understood in the design of interventions that seek to conserve biodiversity and ecosystem services. We sought to investigate the synergies and trade-offs in safeguarding ecosystem services and biodiversity in South Africa's Little Karoo. We used data on three ecosystem services--carbon storage, water recharge, and fodder provision--and data on biodiversity to examine several conservation planning scenarios. First, we investigated the amount of each ecosystem service captured incidentally by a conservation plan to meet targets for biodiversity only while minimizing opportunity costs. We then examined the costs of adding targets for ecosystem services into this conservation plan. Finally, we explored trade-offs between biodiversity and ecosystem service targets at a fixed cost. At least 30% of each ecosystem service was captured incidentally when all of biodiversity targets were met. By including data on ecosystem services, we increased the amount of services captured by at least 20% for all three services without additional costs. When biodiversity targets were reduced by 8%, an extra 40% of fodder provision and water recharge were obtained and 58% of carbon could be captured for the same cost. The opportunity cost (in terms of forgone production) of safeguarding 100% of the biodiversity targets was about US$500 million. Our results showed that with a small decrease in biodiversity target achievement, substantial gains for the conservation of ecosystem services can be achieved within our biodiversity priority areas for no extra cost.

Assessment of land use impact on water-related ecosystem services capturing the integrated terrestrial-aquatic system

Although the importance of green (evaporative) water flows in delivering ecosystem services has been recognized, most operational impact assessment methods still focus only on blue water flows. In this paper, we present a new model to evaluate the effect of land use occupation and transformation on water quantity. Conceptually based on the supply of ecosystem services by terrestrial and aquatic ecosystems, the model is developed for, but not limited to, land use impact assessment in life cycle assessment (LCA) and requires a minimum amount of input data. Impact is minimal when evapotranspiration is equal to that of the potential natural vegetation, and maximal when evapotranspiration is zero or when it exceeds a threshold value derived from the concept of environmental water requirement. Three refinements to the model, requiring more input data, are proposed. The first refinement considers a minimal impact over a certain range based on the boundary evapotranspiration of the potential natural vegetation. In the second refinement the effects of evaporation and transpiration are accounted for separately, and in the third refinement a more correct estimate of evaporation from a fully sealed surface is incorporated. The simplicity and user friendliness of the proposed impact assessment method are illustrated with two examples.

Ecosystem service benefits of contrasting conservation strategies in a human-dominated region

The hope among policy-makers and scientists alike is that conservation strategies designed to protect biodiversity also provide direct benefits to people by protecting other vital ecosystem services. The few studies that have examined the delivery of ecosystem services by existing conservation efforts have concentrated on large, 'wilderness'-style biodiversity reserves. However, such reserves are not realistic options for densely populated regions. Here, we provide the first analyses that compare representation of biodiversity and three other ecosystem services across several contrasting conservation strategies in a human-dominated landscape (England). We show that small protected areas and protected landscapes (restrictive zoning) deliver high carbon storage and biodiversity, while existing incentive payment (agri-environment) schemes target areas that offer little advantage over other parts of England in terms of biodiversity, carbon storage and agricultural production. A fourth ecosystem service-recreation-is under-represented by all three strategies. Our findings are encouraging as they illustrate that restrictive zoning can play a major role in protecting natural capital assets in densely populated regions. However, trade-offs exist even among the four ecosystem services we considered, suggesting that a portfolio of conservation and sustainability investments will be needed to deliver both biodiversity and the other ecosystem services demanded by society.

Vegetation mapping of the Mond Protected Area of Bushehr Province (south-west Iran)

Arid regions of the world occupy up to 35% of the earth's surface, the basis of various definitions of climatic conditions, vegetation types or potential for food production. Due to their high ecological value, monitoring of arid regions is necessary and modern vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps. Sixteen map units covering 12 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata, Salicornia europaea-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced.

Ecological correlates of risk and incidence of West Nile virus in the United States

West Nile virus, which was recently introduced to North America, is a mosquito-borne pathogen that infects a wide range of vertebrate hosts, including humans. Several species of birds appear to be the primary reservoir hosts, whereas other bird species, as well as other vertebrate species, can be infected but are less competent reservoirs. One hypothesis regarding the transmission dynamics of West Nile virus suggests that high bird diversity reduces West Nile virus transmission because mosquito blood-meals are distributed across a wide range of bird species, many of which have low reservoir competence. One mechanism by which this hypothesis can operate is that high-diversity bird communities might have lower community-competence, defined as the sum of the product of each species' abundance and its reservoir competence index value. Additional hypotheses posit that West Nile virus transmission will be reduced when either: (1) abundance of mosquito vectors is low; or (2) human population density is low. We assessed these hypotheses at two spatial scales: a regional scale near Saint Louis, MO, and a national scale (continental USA). We found that prevalence of West Nile virus infection in mosquito vectors and in humans increased with decreasing bird diversity and with increasing reservoir competence of the bird community. Our results suggest that conservation of avian diversity might help ameliorate the current West Nile virus epidemic in the USA.

An operational model for mainstreaming ecosystem services for implementation

Research on ecosystem services has grown markedly in recent years. However, few studies are embedded in a social process designed to ensure effective management of ecosystem services. Most research has focused only on biophysical and valuation assessments of putative services. As a mission-oriented discipline, ecosystem service research should be user-inspired and user-useful, which will require that researchers respond to stakeholder needs from the outset and collaborate with them in strategy development and implementation. Here we provide a pragmatic operational model for achieving the safeguarding of ecosystem services. The model comprises three phases: assessment, planning, and management. Outcomes of social, biophysical, and valuation assessments are used to identify opportunities and constraints for implementation. The latter then are transformed into user-friendly products to identify, with stakeholders, strategic objectives for implementation (the planning phase). The management phase undertakes and coordinates actions that achieve the protection of ecosystem services and ensure the flow of these services to beneficiaries. This outcome is achieved via mainstreaming, or incorporating the safeguarding of ecosystem services into the policies and practices of sectors that deal with land- and water-use planning. Management needs to be adaptive and should be institutionalized in a suite of learning organizations that are representative of the sectors that are concerned with decision-making and planning. By following the phases of our operational model, projects for safeguarding ecosystem services are likely to empower stakeholders to implement effective on-the-ground management that will achieve resilience of the corresponding social-ecological systems.

Field evidence that ecosystem service projects support biodiversity and diversify options

Ecosystem service approaches to conservation are being championed as a new strategy for conservation, under the hypothesis that they will broaden and deepen support for biodiversity protection. Where traditional approaches focus on setting aside land by purchasing property rights, ecosystem service approaches aim to engage a much wider range of places, people, policies, and financial resources in conservation. This is particularly important given projected intensification of human impacts, with rapid growth in population size and individual aspirations. Here we use field research on 34 ecosystem service (ES) projects and 26 traditional biodiversity (BD) projects from the Western Hemisphere to test whether ecosystem service approaches show signs of realizing their putative potential. We find that the ES projects attract on average more than four times as much funding through greater corporate sponsorship and use of a wider variety of finance tools than BD projects. ES projects are also more likely to encompass working landscapes and the people in them. We also show that, despite previous concern, ES projects not only expand opportunities for conservation, but they are no less likely than BD projects to include or create protected areas. Moreover, they do not draw down limited financial resources for conservation but rather engage a more diverse set of funders. We also found, however, that monitoring of conservation outcomes in both cases is so infrequent that it is impossible to assess the effectiveness of either ES or BD approaches.

Birds defend oil palms from herbivorous insects

Top-down forces are expected to be important in regulating herbivore populations in most agricultural systems where primary productivity is high and species diversity is low. Under such conditions, trophic cascades are predicted to occur when predator populations are reduced or removed. Studies on how predator removal indirectly affects herbivory rates in agricultural systems are lacking. Through a bird-exclosure experiment, I test the hypothesis that insectivorous birds indirectly defend oil palms (Elaeis guineensis) from herbivorous insects. Results show that bird exclusion significantly increased herbivory damage to oil palms, and that the size of this exclusion effect increased with bird density, although the latter result was not statistically significant. These findings suggest that insectivorous birds deliver a natural pest control service for oil palm agriculture, which is important not only for the direct benefits it delivers for human welfare, but also in strengthening the economic justifications for conserving the remaining natural habitats and biodiversity in agricultural landscapes.