Research On Rainwater Resources And Its Effective Utilization In Baoding Area

The agricultural production holds an important position in Baoding area,winter wheat and summer corn are the main grain crops and cotton is the main cash crop.The water resources used in agriculture include rainwater resources used directly by crops and surface water resources or underground water resources which is used through irrigation.There have been lots of rainwater waste because of lacking in research on rainwater resources utilization and in perfect engineering technology in Baoding area.To make full use of rainwater is important to alleivate the water resources crisis and improve the ecological environment,the main objectives can make more rainwater turn into soilwater that can be utilized by crops directly and decrease the crops requirments for the surface and ground water resources.The precipitation frequencies is analysed according to 1956~2000 years of rainfall record series in Baoding area.The features of distribution of rainfall are detailed evaluated.Firstly,the distribution of monthly precipitation is not even.for instance.the annual rainfall amount is about 548mm in whole year,about 80% of them in summer season.secondly,yearly variation of rainfall is greater.Thirdly,the abundant years usually are followed by short years, but the important changes have taken place in the last decades.Before 70's the abundant years took the dominant position,from the 70's to the middle of 80's the short years took place more frequently than ever.after the later of 80's,the short years hold the main position.The above knowledge is instructive for guiding the rainwater resources effective utilization.Based on the analysis of crop structure and crop yield according to the statistic data in 1949~2000 year.the total water consumption of main crops and the amount of rainwater utilized have been calculated.The rapid increase in water demand for crops production after the late eighties is the one of main reasons of the water resources crisis in Baoding area.The efficient precipitation,the water demand and the deficiencies of main crops in different typical years and in different growth period in Baoding plain have been studied in detail.The factors of water use efficiency of different crops have been put forward through the analysis of test data in typical year.Based on the above studies.the different programs on how to use the rainwater resources efficiently is developed .which is decided by the water deficiency amount foragricultural production.A series of measures have been put forword.First,different geological regio should take different methods.Second.the rainwater utilization through collection and storage projects or through reduction in evaportranspiration and increasion in infiltration should be combinated organically.Third,the high efficiency of rainwater's utilization should be attained.Therefore,water resources crisis can be alleivated efficiently and the agriculture sustainable development can be improved in Baoding Area...