不同种植方式对棉田土壤温度、棉花耗水和生长的影响

Effects of different planting patterns on soil temperature, water use and growth of cotton

通过2010—2011年大田试验,研究了平作、沟播和地膜覆盖(沟播+地膜覆盖)下棉花生长、水分消耗以及棉田地温变化情况。结果表明:地膜覆盖对棉花苗期和现蕾期地温日变化、最高温影响最大,通过提高土壤温度的最高值来影响土壤温度变化,开花结铃期以后种植方式对地温的影响不明显;不同种植方式对土壤水分也产生了一定影响,覆膜处理的土壤含水量高于其他2种处理,2010年覆膜和沟播处理比平作处理下的水分利用效率分别提高62.4%和25.3%,2011年为26.1%和10.3%;覆膜处理下的棉花净光合速率、生物量和籽棉产量都高于平作和沟播处理,而沟播与平作间的差异不明显;与平作相比,2010和2011年覆膜和沟播处理下的棉花水分利用效率分别提高了0.17、0.10 kg.m-3和0.10、0.03 kg.m-3。覆膜处理与沟播和平作处理相比,能够提高棉花生育前期的地温,有效地保持土壤水分,有利于棉花增产,最终提高了水分利用效率。

This study was undertaken to examine the effects of fiat planting, furrow sowing and film-mulching-bed planting on soil temperature, water use and growth of cotton. Results showed that film-mulChing-bed planting increased soil temperature by increasing the daily maximum temperature in the early growth stages of cotton. After flowering, the effects were not obvious. At the same time film-bed and furrow sowing could conserve soil water and reduce soil evapora- tion. The amount of field water use under film-bed planting was significantly lower than that under furrow and flat sowing by 62.4% and 25.3% in the growth season of 2010, while by 26.1% and 10.3% in 2011. As a result, cotton net photosynthetic rate, biomass and final yield under film-mulching-bed planting were higher than that under furrow and fiat planting. Compared with flat sowing, water use efficiency under film-bed and furrow planting was obviously improved by 62.4% and 25.3% for the season of 2010, while by 26.1% and 10.3% in 2011. Though furrow planting was better in soil moisture conservation than flat planting, no significant difference was found on the cotton yield of the two practices.