Managing water in agriculture for food production and other ecosystem services

https://doi.org/10.1016/j.agwat.2009.03.017Get rights and content

Abstract

Agricultural systems as well as other ecosystems generate ecosystem services, i.e., societal benefits from ecological processes. These services include, for example, nutrient reduction that leads to water quality improvements in some wetlands and climatic regulation through recycling of precipitation in rain forests. While agriculture has increased ‘provisioning’ ecosystem services, such as food, fiber and timber production, it has, through time, substantially impacted other ecosystem services. Here we review the trade-offs among ecosystem services that have been generated by agriculture-induced changes to water quality and quantity in downstream aquatic systems, wetlands and terrestrial systems. We highlight emerging issues that need urgent attention in research and policy making. We identify three main strategies by which agricultural water management can deal with these large trade-offs: (a) improving water management practices on agricultural lands, (b) better linkage with management of downstream aquatic ecosystems, and (c) paying more attention to how water can be managed to create multifunctional agro-ecosystems. This can only be done if ecological landscape processes are better understood, and the values of ecosystem services other than food production are also recognized.

Section snippets

Water for ecosystems—a challenge for agricultural water management

Increases in agriculture over the last century have led to substantial improvements in global food security through higher and stabler food production. They have also contributed to economic growth in many countries. Agriculture, including rangelands, now covers roughly 40% of the world's terrestrial surface (Foley et al., 2005), with croplands covering more than 50% of the land area in many river basins in Europe and India and more than 30% in the Americas, Europe and Asia (MA, 2005). Through

Agriculture increases provisioning ecosystem services but reduces other ecosystem services

The relation between ecosystems and the well-being of human society was reviewed in the Millennium Ecosystem Assessment (the MA), a large assessment involving around 1400 scientists and researchers (MA, 2005). The benefits that ecosystems generate for society have been called ecosystem goods and services (Daily, 1997). In the Millennium Ecosystem Assessment ecosystem services were classified into four categories: (1) provisioning (which has been previously called ecosystem goods, and includes

Effects on aquatic systems, coastal zones and wetlands

Streamflow reduction and regulation. Around 66% of all water withdrawn for direct human use is being used for agriculture (Scanlon et al., 2007). The better the irrigation efficiency the lesser the amount of this water that returns to the rivers and aquifers and the more the “consumptive use” will be, i.e., it flows to the atmosphere as evaporation or transpiration (Falkenmark and Lannerstad, 2005). Where field application efficiency is low (for example, in flooded paddy in the monsoonal

Dealing with trade-offs and finding synergies between water for food and other ecosystem services

The need to produce more food globally and the vast negative effects of agriculture and altered hydrology on ecosystem services provide a major challenge for agricultural water management (Molden et al., 2007). The challenge is, in many circumstances, taken seriously at the international level, and in some cases steps are taken even to reverse the effects that have already occurred. The partial rehabilitation of some iconic symbols of past follies, such as the Aral Sea (Pala, 2006) and

Concluding discussion and policy lessons

While agriculture has generated many so-called “provisioning ecosystem services” such as food, fiber and timber, it has substantially altered water quality and water quantity in many places. These alterations have had large impacts on ecosystems and the other ecosystem services they generate and on which human society depends. We have highlighted that these impacts take place not only in downstream aquatic systems and wetlands. They also occur across the terrestrial landscape where vapor flows,

Acknowledgements

Gordon's work was funded by the Swedish Research Council Formas and the Department for Research Cooperation (SAREC) at Swedish International Development Cooperation Agency (Sida). Part of her and Finlayson's work was done when they worked at IWMI and they want to thank IWMI for their support during this time. Many people contributed to the original chapter in the Comprehensive Assessment of Water Management in Agriculture. These include: E.M. Bennett, T.M. Chiuta, D. Coates, N. Ghosh, M.

References (71)

  • T. Agardy et al.

    Coastal systems

    Millennium Ecosystem Assessment. vol. 1, Ecosystems and Human Well-being: Current State and Trends. Findings of the Conditions and Trends Working Group

    (2005)
  • J.M. Anderies

    Minimal models and agroecological policy at the regional scale: an application to salinity problems in Southeastern Australia

    Regional Environmental Change

    (2005)
  • J.S. Baron et al.

    Effects of land cover, water redistribution, and temperature on ecosystem processes in the South Platte Basin

    Ecological Applications

    (1998)
  • E.M. Bennett et al.

    Human impact on erodable phosphorus and eutrophication: a global perspective

    BioScience

    (2001)
  • D. Bossio et al.

    Conserving land—protecting water

  • O. Boucher et al.

    Direct human influence of irrigation on atmospheric water vapour and climate

    Climate Dynamics

    (2004)
  • S.V. Briggs et al.

    Impacts of salinity on biodiversity—clear understanding or muddy confusion?

    Australian Journal of Botany

    (2003)
  • C. Brown et al.

    Decision support systems for environmental flows: lessons from southern Africa

    International Journal of River Basin Management

    (2007)
  • A. Bullock et al.

    The role of wetlands in the hydrological cycle

    Hydrology and the Earth System Sciences

    (2003)
  • S.R. Carpenter et al.

    Surrogates for resilience of social-ecological systems

    Ecosystems

    (2005)
  • T.N. Chase et al.

    Potential impacts on Colorado Rocky Mountain weather due to land use changes on the adjacent Great Plains

    Journal of Geophysical Research-Atmospheres

    (1999)
  • Coravalan, C., Hales, S., McMichael, A. (coordinating lead authors), 2005. Ecosystems and Human Well-being: Health...
  • C. de Fraiture et al.

    Looking ahead to 2050: scenarios of alternative investment approaches

  • R.J. Diaz

    Overview of hypoxia around the world

    Journal of Environmental Quality

    (2001)
  • D. Dudgeon et al.

    Freshwater biodiversity: importance, threats, status and conservation challenges

    Biological Review

    (2005)
  • C.L. Dybas

    Dead zones spreading in world oceans

    BioScience

    (2005)
  • M. Falkenmark et al.

    Consumptive water use to feed humanity—curing a blind spot

    Hydrology and Earth System Sciences

    (2005)
  • P. Farrington et al.

    Controlling dryland salinity by planting trees in the best hydrogeological setting

    Land Degradation and Development

    (1996)
  • C.M. Finlayson et al.

    Inland water systems.

    Millennium Ecosystem Assessment, Conditions and Trends

    (2005)
  • J.A. Foley et al.

    Global consequences of land use

    Science

    (2005)
  • C. Folke et al.

    Regime shifts, resilience, and biodiversity in ecosystem management

    Annual Review of Ecology, Evolution and Systematics

    (2004)
  • Cited by (321)

    View all citing articles on Scopus
    View full text