Agriculture, water, and ecosystems: avoiding the costs of going too far
minimize future impacts, but also to reverse loss and degradation through rehabilitation and, in some cases, full restoration.
An integrated approach to land, wate , and ecosystems at basin or catchment scale is urgently needed to increase multiple benefits and to mitigate detrimental impacts among ecosystem services.
is involves assessing the costs and benefits as well as all known risks to society as a whole
and to individual stakeholders. Societally accepted tradeoffs are unlikely without wide stake- holder discussion of consequences, distribution of costs and benefits, and possible compensa- tion. It is also important that the results feed into processes of social learning about ecosystem behavior and management. A few tools are available to assist in striking tradeoffs (including economic valuation and desktop procedures for establishing environmental flows), but more efficient and less sectorally specific tools are needed. Most of the tools were developed to enable better decisionmaking on well known problems and benefits. Needed are tools to ad- dress the lesser known problems and benefits and to prepare for surprises.
Decisions on tradeoffs under uncertain conditions should be based on a set of alternative scientifically informed arguments, with an understanding of the uncertainties that exist when dealing with ecological forecasting. To minimize the sometimes very high future costs of unexpected social and ecological impacts, it will be necessary to conceptualize uncertainty in decisionmaking. Adaptive management and scenario planning that improve assessment, monitoring, and learning are two components of this conceptualization.
Ongoing attention is required to communicate ecological messages across disciplinary and sectoral boundaries and to relevant policy and decisionmaking levels. e challenge is to pro- duce simple messages about the multiple benefits of an ecosystem and about how eco- systems generate services—without oversimplifying the complexity of ecosystems.
In view of the huge scale of future demands on agriculture to feed humanity and eradicate hunge , and the past undermining of the ecological functions on which agriculture depends, it is essential that we change the way we have been doing business. To do this, we need to:
Address social and environmental inequities and failures in governance and policy as well as on-ground management.
Rehabilitate degraded ecosystems and, where possible, restore lost ecosystems.
Develop institutional and economic measures to prevent further loss and to encour- age further changes in the way we do business.
Increase transparency in decisionmaking about agriculture-related water management and increase the exchange of knowledge about the consequences of these decisions. In the past many changes in ecosystem services have been unintended consequences of decisions taken for other purposes, often because the tradeoffs implicit in the decision- making were not transparent or were not known [well established].
Water and agriculture—a challenge for ecosystem management
Changes in agriculture over the last century have led to substantial increases in food security through higher and more stable food production. However, the way that water has been man- aged in agriculture has caused widescale changes in land cover and watercourses, contributed
There is a need not only to minimize future ecosystem impacts, but also to reverse loss and degradation through rehabilitation and, in some cases, full restoration