The Mekong River Basin, site of the biggest inland fishery in the world, is undergoing massive hydropower development. Planned dams will block critical fish migration routes between the river's downstream floodplains and upstream tributaries. Here we estimate fish biomass and biodiversity losses in numerous damming scenarios using a simple ecological model of fish migration. Our framework allows detailing trade-offs between dam locations, power production, and impacts on fish resources. We find that the completion of 78 dams on tributaries, which have not previously been subject to strategic analysis, would have catastrophic impacts on fish productivity and biodiversity. Our results argue for reassessment of several dams planned, and call for a new regional agreement on tributary development of the Mekong River Basin.

Trading-off Fish Biodiversity, Food Security and Hydropower in the Mekong River Basin

To address the challenges of biodiversity conservation and commodity production, a framework has been proposed that distinguishes between the integration (“land sharing”) and separation (“land sparing”) of conservation and production. Controversy has arisen around this framework partly because many scholars have focused specifically on food production rather than more encompassing notions such as land scarcity or food security. Controversy further surrounds the practical value of partial trade‐off analyses, the ways in which biodiversity should be quantified, and a series of scale effects that are not readily accounted for. We see key priorities for the future in (1) addressing these issues when using the existing framework, and (2) developing alternative, holistic ways to conceptualise challenges related to food, biodiversity, and land scarcity.

Land sparing versus land sharing: Moving forward

Multiple ecosystem services (ES) can respond similarly to social and ecological factors to form bundles. Identifying key social-ecological variables and understanding how they co-vary to produce these consistent sets of ES may ultimately allow the prediction and modelling of ES bundles, and thus, help us understand critical synergies and trade-offs across landscapes. Such an understanding is essential for informing better management of multi-functional landscapes and minimising costly trade-offs. However, the relative importance of different social and biophysical drivers of ES bundles in different types of social-ecological systems remains unclear. As such, a bottom-up understanding of the determinants of ES bundles is a critical research gap in ES and sustainability science.

Here, we evaluate the current methods used in ES bundle science and synthesize these into four steps that capture the plurality of methods used to examine predictors of ES bundles. We then apply these four steps to a cross-study comparison (North and South French Alps) of relationships between social-ecological variables and ES bundles, as it is widely advocated that cross-study comparisons are necessary for achieving a general understanding of predictors of ES associations. We use the results of this case study to assess the strengths and limitations of current approaches for understanding distributions of ES bundles. We conclude that inconsistency of spatial scale remains the primary barrier for understanding and predicting ES bundles. We suggest a hypothesis-driven approach is required to predict relationships between ES, and we outline the research required for such an understanding to emerge.

Unpacking ecosystem service bundles : Towards predictive mapping of synergies and trade-offs between ecosystem services

Relationship between ecological condition and ecosystem services in European rivers, lakes and coastal waters


 Fluvial riparian vegetation (RV) links fluvial and terrestrial ecosystems. It is under significant pressure from anthropogenic activities, and, therefore, the management and restoration of RV are increasingly important worldwide. RV has been investigated from different perspectives, so knowledge on its structure and function is widely distributed. An important step forward is to convert existing knowledge into an overview easily accessible—for example, for use in decision-making and management. We aim to provide an overview of ecosystem services provided by RV by adopting a structured approach to identify the ecosystem services, describe their characteristics, and rank the importance of each service. We evaluate each service within four main riparian vegetation types adopting a global perspective to derive a broad concept. Subsequently, we introduce a guided framework for use in RV management based on our structured approach. We also identify knowledge gaps and evaluate the opportunities an ecosystem service approach offers to RV management.

/pdf/global-overview-of-ecosystem-services-provided-by-riparian-17mzzlptii.pdf

Global Overview of Ecosystem Services Provided by Riparian Vegetation

Dramatic changes in ecosystem services have motivated recent work characterizing their interactions, including identifying trade-offs and synergies. Although time is arguably implicit in these ideas of trade-offs and synergies (e.g., temporal dynamics or changes in ecosystem services), such interactions are routinely inferred based on the spatial relationships among ecosystem services alone (e.g., spatial concordance of ecosystem services indicates synergies, whereas incongruence signifies trade-offs). The limitations of this approach have not been fully explored. We quantified ecosystem service interactions using correlations among contemporary ecosystem services and compared these results to those derived by incorporating change in ecosystem services from an earlier decade. To document change over ~60 years in an urbanizing floodplain, we used aerial photography to map multiple floodplain-associated ecosystem services. Our results demonstrate how incorporating landscape baselines can influence measured synergies and trade-offs. Spatial correlations among contemporary ecosystem services missed several interactions that were detected when using prior baseline ecosystem services. Ignoring the history of ecosystem services and their change over time may result in missed opportunities to foster their synergies and lead to unnecessary trade-offs. Efforts to incorporate ecosystem services into land management should include long-term monitoring and baseline reconstructions of ecosystem services.

/pdf/ecosystem-service-trade-offs-and-synergies-misunderstood-16zyaqlvkj.pdf

Ecosystem service trade-offs and synergies misunderstood without landscape history

1.Increasing demand for benefits provided by riverine ecosystems threatens their sustainable provision. The ecosystem service concept is a promising avenue to inform riverine ecosystem management, but several challenges have prevented the application of this concept.

2.We quantitatively assess the field of riverine ecosystem services’ progress in meeting these challenges. We highlight conceptual and methodological gaps, which have impeded integration of the ecosystem service concept into management.

3.Across 89 relevant studies, 33 unique riverine ecosystem services were evaluated, for a total of 404 ecosystem service quantifications. Studies quantified between one and 23 ecosystem services, although the majority (55%) evaluated three or less. Among studies that quantified more than one service, 58% assessed interactions between services. Most studies (71%) did not include stakeholders in their quantification protocols, and 34% developed future scenarios of ecosystem service provision. Almost half (45%) conducted monetary valuation, using 16 methods. Only 9% did not quantify or discuss uncertainties associated with service quantification. The indicators and methods used to quantify the same type of ecosystem service varied. Only 3% of services used indicators of capacity, flow, and demand in concert.

4.Our results suggest indicators, data sources, and methods for quantifying riverine ecosystem services should be more clearly defined and accurately represent the service they intend to quantify. Furthermore, more assessments of multiple services across diverse spatial extents and of riverine service interactions are needed, with better inclusion of stakeholders. Addressing these challenges will help riverine ecosystem service science inform river management.

5.Synthesis and applications. The ecosystem service concept has great potential to inform riverine ecosystem management and decision making processes. However, this review of riverine ecosystem service quantification uncovers several remaining research gaps, impeding effective use of this tool to manage riverine ecosystems. We highlight these gaps and point to studies showcasing methods that can be used to address them.

This article is protected by copyright. All rights reserved.

https://besjournals.onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2664.13045

A review of riverine ecosystem service quantification: Research gaps and recommendations

River-floodplains are hotspots for many ecosystem services (ES), and thus, understanding how these services are spatially organized along river systems is essential. General principles from river-floodplain ecology may provide guidance for understanding these spatial patterns, yet such concepts have rarely been incorporated into spatial assessments of ES. Using a lens of riverine concepts, we contrasted how floodplain ES capacity and diversity (orchard production, forage production, carbon storage, paddle route quality, fish capacity) vary with longitudinal river-floodplain position. High spatial resolution aerial photography (2006) facilitated detection of floodplain features contributing to the production of ES. We also determined how river reach types are linked to production of ES. We found that ES capacity varied considerably with longitudinal position and reach type. Agricultural capacity was concentrated in lower reaches, high-quality paddle routes in middle-lower reaches, and fish capacity and carbon storage in upper reaches. Furthermore, the highest diversity of ES was concentrated in the lowland floodplain reaches. Our results suggest river-floodplain concepts can improve spatial assessments of ES, increase our understanding of the relationships among biological features and ES, and thus help us better manage some of the key ES trade-offs.

https://esajournals.onlinelibrary.wiley.com/doi/pdf/10.1002/ecs2.1728

Stephanie A. Tomscha

Papers

Ecosystem service trade-offs and synergies misunderstood without landscape history

A review of riverine ecosystem service quantification: Research gaps and recommendations

The spatial organization of ecosystem services in river‐floodplains

A Guide to Historical Data Sets for Reconstructing Ecosystem Service Change over Time

Undervalued and under pressure: A plea for greater attention toward regulating ecosystem services