Impact of Climate and Land-Use Changes on Water Security for Agriculture in Northern China

摘要: Abstract North China is the most important food basket of China, where majority wheat and corn are produced. Most crops grown in irrigated, thus water security security. Since 1980s, drying has been frequently observed, as shown by a reduction precipitation, cutoff riverflow, shrinkage lakes. This increase cannot be explained climate change alone. We propose that intensive land-use this area recent decades had significant impact. The objectives study to develop quantitative model concurrent processes estimate relative contributions each on observed drying. integrated relevant socioeconomic data, data model, carried out detailed multitemporal (decade, year, day) analysis. Results showed greatly changed since 1999. mainly associated with an extremely 1999 national policy ?returning farmland grazing land forest grassland?. found interesting interaction between use runoff, evapotranspiration. During 1970s more than 80%, while only 10% riverflow change. were 45 45% 1980s-1990s 35 55% 1990s-2000s respectively for 1990s also contributed runoff opposite trend was changes Water availability agriculture northern simultaneously stressed extensive rapid Adaptation ecological principles, such farmland/grazing grassland? policy, other adjustments economic developmental strategies can effective tools mitigate shortage problem promote sustainable agricultural development.