Effects Of Conservation Tillage On Saving Water And Increasing Yield In Sloping Land Of Heilongjiang Western Sandy Area

Heilongjiang sand soil area, which is located in the western songnen plain hinterland, is an important part of dry farming area in the north China. It is China's important commodity grain base and high-quality corn production and export base. Long-term since this region development was not paid attention to management and input, the majority output was single mode of production, especially in recent years gradually worsening ecological environment, natural disasters occurred frequently, desertification phenomenon aggravating, land productivity dropped substantially, all of these influence the region agricultural stability and sustainable development seriously.This field plot experiment, which studied the conservation tillage in Heilongjiang western aeolian sandy soil area, was done in Heilongjiang province Dumeng county in 2008 and 2009(including: covering film between furrows, integration technique of ridge tillage and covering film between furrows, ridge tillage, straw mulch). The effects of different measures on soil moisture content, soil water storage and corn biological indicators (including: leaf area, plant height, stem diameter, dry matter accumulation, yield and its constituent elements, etc.) were studied, and put forward the best farmland conservation tillage measure in this area on a comprehensive evaluation.Research results show that the conservation tillage measures have great effect on soil moisture content, water use efficiency, corn biological character indexes and yield. They could enhance the soil moisture content compare with the conventional tillage particularly in the 0~40cm region. Their role in improving soil moisture are: integration technique of ridge tillage and covering film between furrows > covering film between furrows > straw mulch > ridge tillage .The water use efficiency of straw mulching measure is 0.29 percentage points lower than CK, the others are better than ck, integration technique of ridge tillage and covering film between furrows and covering film between furrows are respectively increased by 23.41% and 24.88% compared with CK, significant difference, the ridge tillage measure also improved 3.7% compared with CK. In maize leaf area index, plant height, stem diameter, dry matter accumulation and other biological characters, the conservation tillage measures show similar influence, their role in improving biological characters are: integration technique of ridge tillage and covering film between furrows > covering film between furrows > ridge tillage > CK > straw mulch . In terms of production, integration technique of ridge tillage and covering film between furrows and covering film between furrows are respectively increased by 26.38% and 24.41% compare with CK, they have obvious increasing effect, the ridge tillage measure only improved 4.33% compared with CK. And it only has a generally stimulation effect. Straw mulch has yield reduction effect, it is due to the low soil temperature in the early growth stage of corn inhibited the growth of maize, resulting in reduced its yield is 1.18%.The results of comprehensive test analysis can be seen, the conservation tillage measures except straw mulching measure outside, all of the rest have beneficial effects on maize growth and yield increase, integration technique of ridge tillage and covering film between furrows and covering film between furrows have the most significant effect.Though straw mulching measure has a slightly yield reduction effect, but this measure for the improvement of soil moisture content is obvious. By using grey correlation method, the analysis was done on the input value, output value and water consumption and other factors, a comprehensive assessment of the combined effect of the measures is that integration technique of ridge tillage and covering film between furrows> covering film between furrows > ridge tillage>straw mulch > CK. As a consequence of the above, integration technique of ridge tillage and covering film between furrows measure has the best effect on water saving and yield increasing in this area.