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A review on trade-off analysis of ecosystem services for sustainable land-use management

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Abstract

Ecosystem services are substantial elements for human society. The central challenge to meet the human needs from ecosystems while sustain the Earth’s life support systems makes it urgent to enhance efficient natural resource management for sustainable ecological and socioeconomic development. Trade-off analysis of ecosystem services can help to identify optimal decision points to balance the costs and benefits of the diverse human uses of ecosystems. In this sense, the aim of this paper is to provide key insights into ecosystem services trade-off analysis at different scales from a land use perspective, by comprehensively reviewing the trade-offs analysis tools and approaches that addressed in ecology, economics and other fields. The review will significantly contribute to future research on trade-off analysis to avoid inferior management options and offer a win-win solution based on comprehensive and efficient planning for interacting multiple ecosystem services.

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References

  • Badgley C, Moghtader J, Quintero E et al., 2007. Organic agriculture and the global food supply. Renewable Agriculture and Food Systems, 22(2): 86–108.

    Article  Google Scholar 

  • Balbi S, del Prado A, Gallejones P et al., 2015. Modeling trade-offs among ecosystem services in agricultural production systems. Environmental Modelling & Software, 72: 314–326.

    Article  Google Scholar 

  • Bank W, 2008. Sustainable Land Management Sourcebook. Washington, DC: World Bank.

    Book  Google Scholar 

  • Barbier E B, 2007. Valuing ecosystem services as productive inputs. Economic Policy, 22(49): 178–229.

    Article  Google Scholar 

  • Barraquand F, Martinet V, 2011. Biological conservation in dynamic agricultural landscapes: Effectiveness of public policies and trade-offs with agricultural production. Ecological Economics, 70(5): 910–920.

    Article  Google Scholar 

  • Bekele E G, Lant C L, Soman S et al., 2013. The evolution and empirical estimation of ecological-economic production possibilities frontiers. Ecological Economics, 90: 1–9.

    Article  Google Scholar 

  • Bennett E M, Balvanera P, 2007. The future of production systems in a globalized world. Frontiers in Ecology and the Environment, 5(4): 191–198.

    Article  Google Scholar 

  • Bohensky E L, Reyers B, Van Jaarsveld A S, 2006. Future ecosystem services in a Southern African river basin: A scenario planning approach to uncertainty. Conservation Biology, 20(4): 1051–1061.

    Article  Google Scholar 

  • Brauman K A, Daily G C, Duarte T K et al., 2007. The nature and value of ecosystem services: An overview highlighting hydrologic services. Annual Review of Environment and Resources, 32: 67–98.

    Article  Google Scholar 

  • Briggs S V, Taws N, 2003. Impacts of salinity on biodiversity: Clear understanding or muddy confusion? Australian Journal of Botany, 51(6): 609–617.

    Article  Google Scholar 

  • Briner S, Elkin C, Huber R et al., 2012. Assessing the impacts of economic and climate changes on land-use in mountain regions: A spatial dynamic modeling approach. Agriculture, Ecosystems & Environment, 149: 50–63.

    Article  Google Scholar 

  • Briner S, Huber R, Bebi P et al., 2013. Trade-offs between ecosystem services in a mountain region. Ecology and Society, 18(3): 35.

    Article  Google Scholar 

  • Bryan B A, 2013. Incentives, land use, and ecosystem services: Synthesizing complex linkages. Environmental Science & Policy, 27: 124–134.

    Article  Google Scholar 

  • Butler J R, Wong G Y, Metcalfe D J et al., 2013. An analysis of trade-offs between multiple ecosystem services and stakeholders linked to land use and water quality management in the Great Barrier Reef, Australia. Agriculture, Ecosystems & Environment, 180: 176–191.

    Article  Google Scholar 

  • Carpenter S R, Mooney H A, Agard J et al., 2009. Science for managing ecosystem services: Beyond the Millennium Ecosystem Assessment. Proceedings of the National Academy of Sciences, 106(5): 1305–1312.

    Article  Google Scholar 

  • Castro A J, Verburg P H, Martín-López B et al., 2014. Ecosystem service trade-offs from supply to social demand: A landscape-scale spatial analysis. Landscape and Urban Planning, 132: 102–110.

    Article  Google Scholar 

  • Cavender-Bares J, Polasky S, King E et al., 2015. A sustainability framework for assessing trade-offs in ecosystem services. Ecology and Society, 20(1): 17.

    Article  Google Scholar 

  • Chee Y E, 2004. An ecological perspective on the valuation of ecosystem services. Biological Conservation, 120(4): 549–565.

    Article  Google Scholar 

  • Cheung W W, Sumaila U R, 2008. Trade-offs between conservation and socio-economic objectives in managing a tropical marine ecosystem. Ecological Economics, 66(1): 193–210.

    Article  Google Scholar 

  • Chisasa J, Makina D, 2013. Bank credit and agricultural output in South Africa: A Cobb-Douglas empirical analysis. International Business & Economics Research Journal (IBER), 12(4): 387–398.

    Article  Google Scholar 

  • Chisholm R A, 2010. Trade-offs between ecosystem services: Water and carbon in a biodiversity hotspot. Ecological Economics, 69(10): 1973–1987.

    Article  Google Scholar 

  • Costanza R, d’ Arge R, De Groot R et al., 1998. The value of the world’s ecosystem services and natural capital. Ecological Economics, 1(25): 3–15.

    Article  Google Scholar 

  • Crossman N D, Bryan B A, 2009. Identifying cost-effective hotspots for restoring natural capital and enhancing landscape multifunctionality. Ecological Economics, 68(3): 654–668.

    Article  Google Scholar 

  • Crossman N D, Bryan B A, de Groot R S et al., 2013. Land science contributions to ecosystem services. Current Opinion in Environmental Sustainability, 5(5): 509–514.

    Article  Google Scholar 

  • Crossman N D, Bryan B A, Summers D M, 2011. Carbon payments and low-cost conservation. Conservation Biology, 25(4): 835–845.

    Article  Google Scholar 

  • Cumming G, 2005. Ecology in global scenarios. Ecosystems and Human Well-being: 45.

    Google Scholar 

  • Daily G C, Alexander S, Ehrlich P R et al., 1997. Ecosystem Services: Benefits Supplied to Human Societies by Natural Ecosystems. Ecological Society of America Washington (DC).

    Google Scholar 

  • Daily G C, Polasky S, Goldstein J et al., 2009. Ecosystem services in decision making: Time to deliver. Frontiers in Ecology and the Environment, 7(1): 21–28.

    Article  Google Scholar 

  • De Groot R, Fisher B, Christie M et al., 2010a. Integrating the ecological and economic dimensions in biodiversity and ecosystem service valuation. In: The Economics of Ecosystems and Biodiversity (TEEB): Ecological and Economic Foundations. Earthscan.

    Google Scholar 

  • De Groot R S, Alkemade R, Braat L et al., 2010b. Challenges in integrating the concept of ecosystem services and values in landscape planning, management and decision making. Ecological Complexity, 7(3): 260–272.

    Article  Google Scholar 

  • Deng X Z, Li Z H, Huang J K et al., 2013. A revisit to the impacts of land use changes on the human wellbeing via altering the ecosystem provisioning services. Advances in Meteorology, 2013.

    Google Scholar 

  • Deng X Z, Zhao Y H, Wu F et al., 2011. Analysis of the trade-off between economic growth and the reduction of nitrogen and phosphorus emissions in the Poyang Lake Watershed, China. Ecological Modelling, 222(2): 330–336.

    Article  Google Scholar 

  • Dymond J R, Ausseil A-G E, Ekanayake J C et al., 2012. Tradeoffs between soil, water, and carbon: A national scale analysis from New Zealand. Journal of Environmental Management, 95(1): 124–131.

    Article  Google Scholar 

  • Elmqvist T, Tuvendal M, Krishnaswamy J et al., 2013. Managing trade-offs in ecosystem services. In: Kumar P, Thiaw I (eds.). Values, Payments and Institutions for Ecosystem Management. Cheltenham: Edward Elgar Publishing, 70–89.

    Google Scholar 

  • Falkenmark M, 2003. Freshwater as shared between society and ecosystems: From divided approaches to integrated challenges. Philosophical transactions of the Royal Society B: Biological Sciences, 358(1440): 2037–2049.

    Article  Google Scholar 

  • Falloon P, Betts R, 2010. Climate impacts on European agriculture and water management in the context of adaptation and mitigation: The importance of an integrated approach. Science of the Total Environment, 408(23): 5667–5687.

    Article  Google Scholar 

  • Farley J, 2012. Ecosystem services: The economics debate. Ecosystem Services, 1(1): 40–49.

    Article  Google Scholar 

  • Farrell M J, 1957. The measurement of productive efficiency. Journal of the Royal Statistical Society. Series A (General): 253–290.

    Google Scholar 

  • Fontana V, Radtke A, Fedrigotti V B et al., 2013. Comparing land-use alternatives: Using the ecosystem services concept to define a multi-criteria decision analysis. Ecological Economics, 93: 128–136.

    Article  Google Scholar 

  • Garland T, 2014. Quick guide: Trade-offs. Current Biology, 24(2): R60–R61.

    Article  Google Scholar 

  • Goldstein J H, Caldarone G, Duarte T K et al., 2012. Integrating ecosystem-service tradeoffs into land-use decisions. Proceedings of the National Academy of Sciences, 109(19): 7565–7570.

    Article  Google Scholar 

  • Greiner R, Cacho O, 2001. On the efficient use of a catchment’s land and water resources: Dryland salinization in Australia. Ecological Economics, 38(3): 441–458.

    Article  Google Scholar 

  • Grosskopf S, Hayes K and Yaisawarng S, 1992. Measuring economies of diversification: A frontier approach. Journal of Business & Economic Statistics, 10(4): 453–459.

    Google Scholar 

  • Haase D, Schwarz N, Strohbach M et al., 2012. Synergies, trade-offs, and losses of ecosystem services in urban regions: An integrated multiscale framework applied to the Leipzig-Halle Region, Germany. Ecology and Society, 17(3): 22.

    Article  Google Scholar 

  • Haines-Young R, Potschin M, Kienast F, 2012. Indicators of ecosystem service potential at European scales: Mapping marginal changes and trade-offs. Ecological Indicators, 21: 39–53.

    Article  Google Scholar 

  • Holland R A, Eigenbrod F, Armsworth P R et al., 2011. The influence of temporal variation on relationships between ecosystem services. Biodiversity and Conservation, 20(14): 3285–3294.

    Article  Google Scholar 

  • Holling C S, 1973. Resilience and stability of ecological systems. Annual Review of Ecology and Systematics, 1–23.

    Google Scholar 

  • Huang I B, Keisler J, Linkov I, 2011. Multi-criteria decision analysis in environmental sciences: Ten years of applications and trends. Science of the Total Environment, 409(19): 3578–3594.

    Article  Google Scholar 

  • Huber R, Bugmann H, Buttler A et al., 2013. Sustainable land-use practices in European mountain regions under global change: An integrated research approach. Ecology and Society, 18(3): 37.

    Google Scholar 

  • Jackson B, Pagella T, Sinclair F et al., 2013. Polyscape: A GIS mapping framework providing efficient and spatially explicit landscape-scale valuation of multiple ecosystem services. Landscape and Urban Planning, 112: 74–88.

    Article  Google Scholar 

  • Jiang M K, Bullock J Mand Hooftman D A, 2013. Mapping ecosystem service and biodiversity changes over 70 years in a rural English county. Journal of Applied Ecology, 50(4): 841–850.

    Article  Google Scholar 

  • King E, Cavender-Bares J, Balvanera P et al., 2015. Trade-offs in ecosystem services and varying stakeholder preferences: evaluating conflicts, obstacles, and opportunities. Ecology and Society, 20(3): 25.

    Article  Google Scholar 

  • Kirchner M, Schmidt J, Kindermann G et al., 2015. Ecosystem services and economic development in Austrian agricultural landscapes: The impact of policy and climate change scenarios on trade-offs and synergies. Ecological Economics, 109: 161–174.

    Article  Google Scholar 

  • Laniak G F, Olchin G, Goodall J et al., 2013. Integrated environmental modeling: A vision and roadmap for the future. Environmental Modelling & Software, 39: 3–23.

    Article  Google Scholar 

  • Lester S E, Costello C, Halpern B S et al., 2013. Evaluating tradeoffs among ecosystem services to inform marine spatial planning. Marine Policy, 38: 80–89.

    Article  Google Scholar 

  • Li Z H, Deng X Z, Huang J K et al., 2013. Critical studies on integrating land-use induced effects on climate regulation services into impact assessment for human well-being. Advances in Meteorology, 1–14. doi: 10.1155/2013/831250.

    Google Scholar 

  • Lü Y, Fu B, Feng X et al., 2012. A policy-driven large scale ecological restoration: Quantifying ecosystem services changes in the Loess Plateau of China. PloS One, 7(2): e31782.

    Article  Google Scholar 

  • MA, 2005a). Ecosystems and Human Well-being. Washington, DC: Island Press.

    Google Scholar 

  • MA, 2005b). Ecosystems and Human Well-being: Current State and Trends. Washington, DC: Island Press.

    Google Scholar 

  • MA, 2005c). Our Human Planet: Summary for Decision-makers. Island Press.

    Google Scholar 

  • Maes J, Paracchini M, Zulian G et al., 2012. Synergies and trade-offs between ecosystem service supply, biodiversity, and habitat conservation status in Europe. Biological Conservation, 155: 1–12.

    Article  Google Scholar 

  • Maron M, Cockfield G, 2008. Managing trade-offs in landscape restoration and revegetation projects. Ecological Applications, 18(8): 2041–2049.

    Article  Google Scholar 

  • Martín-López B, Iniesta-Arandia I, García-Llorente M et al., 2012. Uncovering ecosystem service bundles through social preferences. PloS One, 7(6): e38970.

    Article  Google Scholar 

  • Maskell L C, Crowe A, Dunbar M J et al., 2013. Exploring the ecological constraints to multiple ecosystem service delivery and biodiversity. Journal of Applied Ecology, 50(3): 561–571.

    Article  Google Scholar 

  • Mason N W, Ausseil A-G E, Dymond J R et al., 2012. Will use of non-biodiversity objectives to select areas for ecological restoration always compromise biodiversity gains? Biological Conservation, 155: 157–168.

    Article  Google Scholar 

  • Mastrangelo M E, Laterra P, 2015. From biophysical to social-ecological trade-offs: Integrating biodiversity conservation and agricultural production in the Argentine Dry Chaco. Ecology and Society, 20(1): 20.

    Article  Google Scholar 

  • McShane T O, Hirsch P D, Trung T C et al., 2011. Hard choices: Making trade-offs between biodiversity conservation and human well-being. Biological Conservation, 144(3): 966–972.

    Article  Google Scholar 

  • MEA, 2005. Ecosystems and Human Well-being: Scenarios: Findings of the Scenarios Working Group. Island Press.

    Google Scholar 

  • Medcalf K, Small N, Finch C et al., 2014). JNCC Report No: 514. Further Development of a Spatial Framework for Mapping Ecosystem Services.

  • Mouchet M A, Lamarque P, Martín-López B et al., 2014. An interdisciplinary methodological guide for quantifying associations between ecosystem services. Global Environmental Change, 28: 298–308.

    Article  Google Scholar 

  • Naidoo R, Ricketts T H, 2006. Mapping the economic costs and benefits of conservation. PLoS Biology, 4(11): e360.

    Article  Google Scholar 

  • Nelson E, Mendoza G, Regetz J et al., 2009. Modeling multiple ecosystem services, biodiversity conservation, commodity production, and tradeoffs at landscape scales. Frontiers in Ecology and the Environment, 7(1): 4–11.

    Article  Google Scholar 

  • Nelson E, Polasky S, Lewis D J et al., 2008. Efficiency of incentives to jointly increase carbon sequestration and species conservation on a landscape. Proceedings of the National Academy of Sciences, 105(28): 9471–9476.

    Article  Google Scholar 

  • Nguyen T T, Verdoodt A, Van Y T et al., 2015. Design of a GIS and multi-criteria based land evaluation procedure for sustainable land-use planning at the regional level. Agriculture, Ecosystems & Environment, 200: 1–11.

    Article  Google Scholar 

  • Paterson S, Bryan B A, 2012. Food-carbon trade-offs between agriculture and reforestation land uses under alternate market-based policies. Ecology and Society, 17(3): 21.

    Article  Google Scholar 

  • Pattanayak S K, 2004. Valuing watershed services: Concepts and empirics from Southeast Asia. Agriculture, Ecosystems & Environment, 104(1): 171–184.

    Article  Google Scholar 

  • Polasky S, Nelson E, Camm J et al., 2008. Where to put things? Spatial land management to sustain biodiversity and economic returns. Biological Conservation, 141(6): 1505–1524.

    Article  Google Scholar 

  • Polasky S, Nelson E, Pennington D et al., 2011. The impact of land-use change on ecosystem services, biodiversity and returns to landowners: A case study in the State of Minnesota. Environmental and Resource Economics, 48(2): 219–242.

    Article  Google Scholar 

  • Power A G, 2010. Ecosystem services and agriculture: Tradeoffs and synergies. Philosophical Transactions of the Royal Society B: Biological Sciences, 365(1554): 2959–2971.

    Article  Google Scholar 

  • Raudsepp-Hearne C, Peterson G D, Bennett E, 2010. Ecosystem service bundles for analyzing tradeoffs in diverse landscapes. Proceedings of the National Academy of Sciences, 107(11): 5242–5247.

    Article  Google Scholar 

  • Ring I, 2008. Biodiversity governance: Adjusting local costs and global benefits. In: Public and Private in Natural Resource Governance: A False Dichotomy? London, UK: Earthscan.

    Google Scholar 

  • Ring I, Hansjürgens B, Elmqvist T et al., 2010. Challenges in framing the economics of ecosystems and biodiversity: The TEEB initiative. Current Opinion in Environmental Sustainability, 2(1): 15–26.

    Article  Google Scholar 

  • Rockström J, Steffen W, Noone K et al., 2009. A safe operating space for humanity. Nature, 461(7263): 472–475.

    Article  Google Scholar 

  • Rodríguez J, Beard T, Agard J et al., 2005. Interactions among ecosystem services. Millennium Ecosystem Assessment (ed.). Ecosystems and Human Well-being: Scenarios (Vol. II). Washington, DC: Island Press.

    Google Scholar 

  • Rodríguez J P, Beard T D, Bennett E M et al., 2006. Trade-offs across space, time, and ecosystem services. Ecology and Society, 11(1): 28.

    Google Scholar 

  • Ruhl J B, Kraft S, E, Lant C L, 2007. The Law and Policy of Ecosystem Services. Cambridge Univ Press.

    Google Scholar 

  • Ryffel A N, Rid W, Grêt-Regamey A, 2014. Land use trade-offs for flood protection: A choice experiment with visualizations. Ecosystem Services, 10: 111–123.

    Article  Google Scholar 

  • Sanon S, Hein T, Douven W et al., 2012. Quantifying ecosystem service trade-offs: The case of an urban floodplain in Vienna, Austria. Journal of Environmental Management, 111: 159–172.

    Article  Google Scholar 

  • Seppelt R, Lautenbach S, Volk M, 2013. Identifying trade-offs between ecosystem services, land use, and biodiversity: A plea for combining scenario analysis and optimization on different spatial scales. Current Opinion in Environmental Sustainability, 5(5): 458–463.

    Article  Google Scholar 

  • Sheng W P, Ren S J, Yu G R et al., 2011. Patterns and driving factors of WUE and NUE in natural forest ecosystems along the North-South Transect of Eastern China. Journal of Geographical Sciences, 21(4): 651–665.

    Article  Google Scholar 

  • Silvestri S, Kershaw F, 2010. Framing the flow: Innovative approaches to understand, protect and value ecosystem services across linked habitats. United Nations Environment Programme (UNEP).

    Google Scholar 

  • Swallow B M, Sang J K, Nyabenge M et al., 2009. Tradeoffs, synergies and traps among ecosystem services in the Lake Victoria basin of East Africa. Environmental Science & Policy, 12(4): 504–519.

    Article  Google Scholar 

  • Tallis H, Kareiva P, Marvier M et al., 2008. An ecosystem services framework to support both practical conservation and economic development. Proceedings of the National Academy of Sciences, 105(28): 9457–9464.

    Article  Google Scholar 

  • Tallis H, Ricketts T, Guerry A et al., 2011). InVEST 2.1 beta User’s Guide. The Natural Capital Project. Stanford.

  • Tansley A G, 1935. The use and abuse of vegetational concepts and terms. Ecology, 16(3): 284–307.

    Article  Google Scholar 

  • TEEB, 2010). In: Kumar P (ed.). The Economics of Ecosystems and Biodiversity: Ecological and Economic Foundations. London: Earthscan.

  • Tietenberg T, 1988. Environmental and Natural Resources. Economics.

    Google Scholar 

  • Tilman D, Cassman K G, Matson P A et al., 2002. Agricultural sustainability and intensive production practices. Nature, 418(6898): 671–677.

    Article  Google Scholar 

  • UKNEA, 2011. The United Kingdom National Ecosystem Assessment: Technical Report. Cambridge, UK: UNEP-WCMC.

    Google Scholar 

  • van den Belt M, Bowen T, Slee K et al., 2013. Flood protection: Highlighting an investment trap between built and natural capital. JAWRA Journal of the American Water Resources Association, 49(3): 681–692.

    Article  Google Scholar 

  • Van Huylenbroeck G, 1997. Multicriteria tools for the trade-off analysis in rural planning between economic and environmental objectives. Applied Mathematics and Computation, 83(2): 261–280.

    Article  Google Scholar 

  • Varian H R, Repcheck J, 2010. Intermediate Microeconomics: A Modern Approach. New York: WW Norton.

    Google Scholar 

  • Vollmer D, Pribadi D O, Remondi F et al., 2015. Prioritizing ecosystem services in rapidly urbanizing river basins: A spatial multi-criteria analytic approach. Sustainable Cities and Society, 20: 237–252.

    Article  Google Scholar 

  • Wang Z, Mao D, Li L et al., 2015. Quantifying changes in multiple ecosystem services during 1992–2012 in the Sanjiang Plain of China. Science of the Total Environment, 514: 119–130.

    Article  Google Scholar 

  • Wendland K J, Honzák M, Portela R et al., 2010. Targeting and implementing payments for ecosystem services: Opportunities for bundling biodiversity conservation with carbon and water services in Madagascar. Ecological Economics, 69(11): 2093–2107.

    Article  Google Scholar 

  • Willemen L, Veldkamp A, Verburg P et al., 2012. A multi-scale modelling approach for analysing landscape service dynamics. Journal of Environmental Management, 100: 86–95.

    Article  Google Scholar 

  • Yahdjian L, Sala O E, Havstad K M, 2015. Rangeland ecosystem services: Shifting focus from supply to reconciling supply and demand. Frontiers in Ecology and the Environment, 13(1): 44–51.

    Article  Google Scholar 

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Authors and Affiliations

  1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, 100101, China

    Xiangzheng Deng & Zhihui Li

  2. Center for Chinese Agricultural Policy, CAS, Beijing, 100101, China

    Xiangzheng Deng & Zhihui Li

  3. University of Chinese Academy of Sciences, Beijing, 100049, China

    Zhihui Li

  4. Department of Economics, The University of Waikato, Hamilton, New Zealand

    John Gibson

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  1. Xiangzheng Deng
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Correspondence to Xiangzheng Deng.

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Foundation: China National Natural Science Funds for Distinguished Young Scholar, No.71225005; The Key Project in the National Science & Technology Pillar Program of China, No.2013BACO3B00

Author: Deng Xiangzheng, PhD and Professor, land use change, global change and regional sustainable development.

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Deng, X., Li, Z. & Gibson, J. A review on trade-off analysis of ecosystem services for sustainable land-use management. J. Geogr. Sci. 26, 953–968 (2016). https://doi.org/10.1007/s11442-016-1309-9

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