CLIMATE- AND LAND USE-INDUCED RISKS TO WATERSHED SERVICES IN THE NYANDO RIVER BASIN, KENYA
CLIMATE- AND LAND USE-INDUCED RISKS TO WATERSHED SERVICES IN THE NYANDO RIVER BASIN, KENYA
复制标题
气候和土地利用对肯尼亚尼安多河流域流域服务造成的风险
DOI：
10.1017/s001447971100007x
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发表时间：
2011
影响因子：
1.6
通讯作者：
J. Sang
中科院分区：
文献类型：
--
作者：
Mwangi Gathenya;H. Mwangi;R. Coe;J. Sang
摘要气候变化和土地利用变化是影响流域水文学及其提供生态系统服务能力的两个因素，如清洁和调节良好的径流以及控制土壤侵蚀和产沙量。土壤水分评估工具SWAT是一个分布式流域尺度的水文模型，包含18个降雨、温度和地表入渗能力的情景，以调查肯尼亚西部3587平方公里Nyando盆地流域服务的空间分布以及这两种力量是如何影响流域服务的。50个子流域的年总产水量变化范围为35~600 mm，年产沙量为0~104t ha−1。与降雨和地表条件变化相比，温度变化对径流和产沙量的影响相对较小。改善地表条件导致更高的入渗率是缓解气候变化对流域服务供应的影响的有效适应战略。应对气候和土地利用变化的空间异质性很大，因此，如果要有效地采取措施改变水文学或适应气候变化，就有必要了解这种异质性。
SUMMARY Climate change and land use change are two forces influencing the hydrology of watersheds and their ability to provide ecosystem services, such as clean and well-regulated streamflow and control of soil erosion and sediment yield. The Soil Water Assessment Tool, SWAT, a distributed, watershed-scale hydrological model was used with 18 scenarios of rainfall, temperature and infiltration capacity of land surface to investigate the spatial distribution of watershed services over the 3587 km2 Nyando basin in Western Kenya and how it is affected by these two forces. The total annual water yield varied over the 50 sub-basins from 35 to 600 mm while the annual sediment yield ranged from 0 to 104 tons ha−1. Temperature change had a relatively minor effect on streamflow and sediment yield compared to change in rainfall and land surface condition. Improvements in land surface condition that result in higher infiltration are an effective adaptation strategy to moderate the effects of climate change on supply of watershed services. Spatial heterogeneity in response to climate and land use change is large, and hence it is necessary to understand it if interventions to modify hydrology or adapt to climate change are to be effective.