Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
WANG Hong-rui, LIU Chang-ming, , MAO Guang-quan, LIU Jie 4
Agricultural water resources is scarce in Beijing.Total amount of agricultural water usage has been reduced gradually since1980.The ratio of the amount of agricultural water to that of total city water is also declining,from61%in the early1980s to53%in1995,to45%in2001.But the ratio of the amount of groundwater usage to that of total agricultural water usage is increasing evidently,from38.5%in1980to65.8%in1995,and to75.6%in2001.Groundwater has become the main source for irrigation.It can also be seen that water scarcity is getting more and more serious from the shift of agricultural water source. This paper gives an all-sided and indepth analysis on agricultural water scarcity.The curr-ent water use policy of Beijing is,water distribution should be given priority to the needs of industry and domestic use because of the features of“large urban area,small suburb”in Beijing.Thus agricultural water can only be distributed in the precondition of ensuring domestic and industrial use.This policy will directly exert an adverse effect on the agricultural production.The findings reveal that Beijing’s water-policy will further aggravate the tension of agricultural water.Some countermeasures and suggestions are put forward to relax the tension.Based on the above analysis,the author gives the following suggestions:(1)Developing water-saving agriculture is the main countermeasure for solving the problem of agricultural water-scarcity.Water-saving agricultural technique includes:dry crop agricultural techniques(including zero tillage,land-membrane cropping,straw cover cultivation,etc.),drought-resistance and alkali-resistance cultivation breeding techniques,paddy rice drought-and alkali-resistence cultivation and open-plant techniques,etc.(2)Building water-saving irrigation projects.(3)Adjusting the crops structure,developing of feed and economic crops;developing stockbreeding,farm produce proces-sing,green ecological agriculture,and rural eco-tourism.(4)Properly developing sewage irrigation.(5)Establishing groundwater reserve source for meeting an emergency in the Yanqi River valley and Huaihe River valley of Huairou District.(6)Now there are many perfect technologies on storm flood utilization in the world.The storm flood leaving Beijing is7×10 8 m 3 (deduct passing water)annually.Exploitation the storm flood,increasing water resources which can be used,will be propitious to relax the tension of agricultural water shortage and water and soil conservation.(7)Artificial catalysis of the ice and snow crystals will raise the precipitation efficiency.So it is also a method of alleviating water scarcity to study the meteorological rule and realize artificial inducement of rainfall.(8)It is very important to strengthen macro and micro management of rural water resources,improve management system of rural water resources,and strengthen irrigating water management.It is also necessary to implement system of water use planning,water supplying quota and collecting water charge by measurement To sum up,in order to realize the sustainable development of agriculture and protect the farmers’economic profit,measures that can be put into practice must be given and implemented.
