Effects Of Different Furrow-Ridge Mulching Ways On Winter Wheat Growth And Soil Environment

A plastic-covered furrow-ridge rainfall harvesting system is being promoted to increase water availability for crops for higher and stable agricultural production in arid areas. The technique which based on the collection and concentration of surface runoff from short slopes is especially useful in arid and semiarid regions where irrigation water is not available or too costly to use. In this system, the plastic-covered ridges served as a rainfall harvesting zone and furrows as a planting zone. The system can make better utilization of light rain by harvesting rainwater through the plastic-covered ridge.The experiment had set different cultivation patterns of furrow-ridge mulching using ordinary film, liquid film and straw and been analyzing on soil moisture, yield, water use efficiency and economic benefits of winter wheat for three years. The objective of the experiment was to explore the effect of soil water conservation, grain yield and income increments of winter wheat under different furrow-ridge mulching cultivation conditions in semi-humid area.(1)The furrow-ridge mulching cultivation pattern with the role of rainwater harvesting, storage and retention could effectively improve soil moisture conditions.In the whole growth period of winter wheat in this experiment during these three years, DM+JG(the ordinary plastic film and straw dual-mulching)and YM+JG(the liquid film and straw dual-mulching)are with the maximum soil moisture content, followed by DM+BU(the ordinary plastic film on furrow and the ridge no-mulching)å'ŒDM+YM(the ordinary plastic and liquid film dual-mulching), YM+BU(the liquid film on furrow and the ridge no-mulching)and YM+YM(the liquid film on furrow-ridge dual-mulching)are with the minimum and unstable rainwater harvesting, which probably because the local ecological environment. The vertical distribution of soil moisture content conditions in 0-200cm soil layer of different mulching ways are different in the different period for the different rainfall conditions between years, but with similar trend in the same period. Soil moisture content in 0-200cm soil layer of mulching ways are higher than CK₁(conventional flat practice)and CK₂(the furrow-ridge no-mulching)because of the effect of rainwater harvesting and retention of the covering material. For 0-40 cm soil layer, the moisture content of the ordinary plastic film and YM+ JG treatments are significantly (P<0.05) higher than CK₁ and CK₂, and DM + JG treatment is particularly evident.(2)Compared to CK₁ and CK₂, in different furrow-ridge mulching cultivation condition, the winter wheat yield in different mulching ways are significantly different that DM+JG treatment is with the highest yield, YM+JG follows, and YM+BU with the lowest in different years. The average of yield in three years with DM+JG and YM+JG were 4879.6 and 4532.5 kg·hm^-2, increasing 39.3% and 29.4% over CK₁ , 35.6% and 25.9% over CK₂, which all showed significantly different compared to CK₁ and CK₂(P<0.05).Three years of experiment show that YM+BU and YM+YM treatments perform instability for increasing production. Wheat yield had a small increase in 2008 and 2009 over CK₁ and CK₂ but in 2010 was not significant.(3)Compared to CK₁ and CK₂, in different furrow-ridge mulching cultivation condition, WUE (water use efficiency) in different mulching ways are significantly different that WUE of DM+JG and YM+JG are the highest, the average of WUE in three years with DM+JG and YM+JG are 14.7 and 13.7 kg·hm^-2·mm^-1 respectively, increasing 39.6% and 30.3% over CK₁ , 33.4% and 24.5% over CK₂, followed by DM+BU and DM+YM treatment, which all show significantly different compared to CK₁ and CK₂(P<0.05). WUE of YM+BU and YM+YM treatments are the lowest.(4)In three years of the experiment, the total investment, yield income and net income of DM+JG , YM+JG and DM+BU treatments were higher than CK₁ and CK₂, and DM+JG>YM+JG>DM+BU. The net income in those three years increase 1452.1(43.2%),977.4(28.9%)and 518.0 yuan·hm^-2(16.6%)over CK₁ and 1416.5(42.6%),941.8(28.2%)and 482.4 yuan·hm^-2(16.1%)over CK₂ respectively. The yield of DM+YM treatment didn't increase by so much total investment and the net income had a small increase over CK₁ and CK₂ in 2008, 2009, and was almost the same with CK₁, CK₂ in 2010. YM+BU and YM+YM treatments made a loss for having a small increase in yield but too much total investment.(5)The effect on the factors of winter wheat yield in different furrow-ridge mulching ways are most obvious to DM+JG and YM+JG. The weight of one thousand of grain increase 1.4 g,1.3 g over CK₁ and 0.4 g,0.3 g over CK₂ respectively; The grain number increase 12.0%,8.5% over CK₁ and 6.1%,2.8% over CK₂ respectively; Spike number increase 20.3%,15.6% over CK₁ and 26.4%,21.5% over CK₂ respectively; DM+BU and DM+YM treatments followed, and YM+BU,YM+YM treatments are the lowest.(6)DM+BU, YM+BU, DM+YM, YM+YM, DM+JG, and YM+JG treatments, from jointing to maturity in the three years of experiment, plant height increases 22.0%, 11.8%, 26.2%, 14.3%, 24.8% and 17.5% over CK₁ and 12.9%, 3.6%, 16.7%, 5.9%, 15.5% and 8.9% over CK₂ respectively, biomass increase 3.1g, 1.6g, 2.8g, 1.2g, 3.5g and 2.1g over CK₁ and 2.1g, 0.6g, 1.8g, 0.2g, 2.5g and 1.1g over CK₂ respectively. DM+BU, DM+YM, DM+JG and YM+JG treatments are better than YM+BU and YM+YM.(7)In different furrow-ridge mulching ways, the content of organic matter and Avail.N and vail.P increase mainly in 20-60 cm, and vail.K in 0-60 cm.The effects of soil available nutrients in different furrow-ridge mulching ways are different between years and the effects on the content of organic matter and Avail.N in 0-60 cm soil layers in different mulching ways are also different. The content of vail.P and vail.K in the ordinary plastic film and straw dual-mulching are the highest and significantly different to conventional flat practice(P<0.05), followed by the ordinary plastic film on furrow and the ridge no-mulching, the liquid film and straw dual-mulching.