The document discusses the significance of rainwater harvesting (RWH) in supporting ecosystems and human well-being, presenting ecosystems as a vital source of livelihood, especially in developing nations. It highlights the degradation of ecosystem services over the last fifty years due to various direct and indirect drivers, including climate change and urbanization, while outlining the benefits of RWH in water regulation and ecosystem rehabilitation. Recommendations emphasize integrating RWH into integrated water resource management (IWRM) and raising awareness of its value in combating ecosystem degradation.

1. Rainwater Harvesting and Ecosystems Elizabeth Khaka UNEP / Division of Environmental Policy Implementation Regional Conference for Southeast Asia on Rainwater Harvesting in IWRM: An Exchange of Practices and Learning 25-26 November, 2008

2. Flow Introduction Ecosystems services Contribution of ecosystems Ecosystems degradation RWH and ecosystems UNEP ecosystems and RWH initiative

3. Introduction Definition ecosystem- ‘a dynamic complex of plant, animal, and microorganism communities and the nonliving environment interacting as a functional unit. Humans are an integral part of ecosystems’. CBD

4. Introduction Ecosystems major source of livelihood to billions Dependency high in developing countries

5. Ecosystems S ervices

6. Provisioning Recreation Regulating

7. Contribution of ecosystems Flood prevention US$350 billion at 1994 Recreational value US$304 billion Reef habitats US$375 billion Fisheries contributes 16-90% of global protein

8. Contribution of ecosystems Malaysia mangrove s US$ 35 million a year Thailand coastal protection US$ 165 million Indonesia mangroves US$ 86 million

9. Ecosystems degradation 60% of ecosystem services (the benefits people obtain from ecosystems) were heavily degraded over the last 50 years (the Millennium Ecosystem Assessment) Especially aquatic ecosystems are declining more rapidly than other ecosystems

10. Framework Ecosystem Services Provisioning (e.g., food, water and fiber) Regulating (e.g., climate regulation and water) Cultural (e.g., spiritual and aesthetic) Supporting (e.g., soil formation) Human Well-being Basic material for a good life Health Good Social Relations Security Freedom of choice and action Direct Drivers of Change Changes in land use Species introduction or removal Technology adaptation and use External inputs (e.g., irrigation) Resource consumption Climate change Natural physical and biological drivers (e.g., volcanoes) Ind irect Drivers of Change Demographic Economic (globalization, trade, market and policy framework) Sociopolitical (governance and institutional framework) Science and Technology Cultural and Religious

11. Drivers of Ecosystem Degradation Climate Change Desertification Frequent Droughts and Floods Over-exploitation Groundwater Surface water Pollution Habitat Change Urbanization Soil Erosion Large Dams Direct Drivers Indirect Drivers Economic Drivers Poverty Sociopolitical Drivers Insensibility of Water Resource Limitation Centralization of Water Supply

12. Climate Change Desertification Maintaining flora-trees grass Frequent Droughts and Floods Mitigate floods -detaining Drought-detain flood water

13. Over-exploitation Improve storage Groundwater recharge Individual and community structures Soil Reduce over exploitation Irrigation Household Industrial

14. Pollution Pollutant Discharges Retaining and detaining urban runoff -reduces the potential for pollutant discharges from overflow Controlling non-point source of pollution is an important broader strategy for the protection of surface water quality in urban areas.

15. Habitat Change Urbanization Prevents unban floods Groundwater recharge Soil Erosion Reduce runoff Trees- vegetation Large Dams Reduce reliance on water storage dams can be reduced

16. Economic Drivers Poverty Improve production –agriculture Catalyst for development Improve access to water and sanitation Reduce time for fetching water-girl child and school Water for sanitation

17. RWH for Ecosystem Services Provisioning Services Fresh Water Food Timber RWH

18. RWH for Ecosystem Services Water Regulation Erosion Regulation Natural Hazard Regulation Water Purification Regulating Services RWH

19. RWH for Ecosystem Services Water Cycling Supporting Services RWH

20. Conclusions and Recommendations Contributes to ecosystems rehabilitation -addresses drivers of ecosystem degradation Plays an important role in ecosystems and human well being Link with ecosystems important to avoid over-abstraction Plan RWH in IWRM. Awareness creation

21. UNEP P ublication on RWH & ecosyst e m s Introduction and background 1a) Introduction, scope 1b) Background: rainwater harvesting the concept 1c) Ecosystems framework and human wellbeing RWH and catchment /watershed management 2 a). RWH and surface water 2 b). RWH and ground water recharge RWH and agriculture 3 a). RWH and crop production 3 b). RWH and livestock production 3 c). RWH and cash crop production (non food production)

22. UNEP P ublication on RWH & ecosyst e m s RWH and forestry 4 a). RWH and forests (incl. aspects on natural and plantation) 4 b). RWH and agroforestry RWH for water supply in rural and urban areas 5 a) RWH and domestic water supply in rural urban context 5 b) RWH and industry RWH in the future 7 a) climate change and adaptation: the role of RWH 7 b) global drivers of change/ ecosystems degradation & water stress Conclusions and recommendations 8 a) Synthesis and discussions 8 b) Policy implications: gaps and pot. ways ahead

23. Thank You