陕北丘陵沟壑区坡地不同耕作法综合效益研究

以在陕北丘陵沟壑区坡耕地不同耕作法试验7 a的资料为依据, 论述了不同耕作法的水分利用、土壤水分平衡及单位面积产量和水土保持等综合效益. 作物生长主要依赖生育期内自然降雨;作物耗水量与每年生育期降雨量及土壤供水量呈显著正相关,不同耕作法之间变化不大,作物主要利用0-120 cm土层内的水分.同一年内不同耕作法的综合效益从优到劣、由高到低的排列顺序为宽梯田＞窄梯田＞水平沟＞平播＞水平阶＞隔坡梯田.而水土保持效益排列顺序为:梯田＞水平沟＞隔坡梯田＞水平阶＞平播＞裸地. 认为坡耕地确实应尽快退耕还林还草,以加速陕北生态环境建设,推进农业结构的战略性调整.

Comprehensive Efficiency Research on Different Cultivations of Slope Land in Loess Hilly and Gully Region

According to detailed data that are gained by 7-year tests of the different cultivation of the slope land in the loess hilly and gully region of the north of Shaanxi province, water use of the different cultivation, water balance, outputs and comprehensive efficiency of soil and water conservation are discussed. The conclusion is that crop grow this mainly dependent on natural rainfall during the growth period; water-consuming content of crop is significantly relative to the rainfall during the growth period per year and water supply content of soil, and crop makes mainly use of soil moisture of 0-120cm layer. The comprehensive efficiency sequence of the different farming sat the same year is broadter race> narrow ter race> level trench >traditional tillae> level bench> alternation of slope and terrace, while the soil and water conservation efficiency sequence is terrace> level trench> alternation of slope and terrace> level bench> traditional tillage>bare land. Finally we think that quitcultivating and resto ring and rebuilding forest and grass should be quickly put into practice in order to accelerate the ecoenvironmental constr uction, and strategic adjustment of agricultural structure should be advanced.