Study on Yield and Quality of Long-ting P.Simonii Carr. with the Technique of Dry Farming and Water Retention Covering;

The paper calculates the soil and water loss caused by the events of precipitation happened in a large scale in the upper stream of Miyun Reservoir on August 10~16, 2005 and the benefits of reduced area-source pollution through typical soil and water conservation measures based on the observed data of monitoring slope plots.

The paper calculates the benefits of reducing flood and sand damages from water and soil conservation measures for the uncontrolled areas (shanxi province) to the north of Hekou-Hongmen section of the Yellow River.

Based on the contrast experiment among different water conservation ways,such as straw,straw covering,film covering and contrast treatment in the growth period of flue-cured tobacco,the effect of different water conservation measures on soil moisture,agronomic characteristic,production and output is studied in this paper.