棉田秸秆覆盖试验研究

在我国水资源严重短缺的北方地区，如何挖掘水资源潜力，提高农作物对水的利用率，是发展节水型农业的重要研究课题。农田秸秆覆盖具有就地取材，易于推广的优点，越来越引起人们的广泛重视和青睐。但对于秸秆覆盖的保墒，节水和增产机理，迄今尚未明了。于1998年通过田间试验，研究了秸秆覆盖对棉田土壤含水量、土壤温度、棉花株高、果枝数、棉铃重、籽棉重及其产量的影响。分析了覆盖保墒的作用时间，土壤昼夜温度变化及棉花长势，并提出土壤含水量变化过程线，田间试验结果表明：秸秆覆盖可使棉田土壤含水量增加，其作用效果主要在苗期和蕾期，秸秆覆盖在白天使土壤温度降低，在夜间则具有保温的作用；覆盖使棉花果枝数，棉铃重 、籽棉重增加，从而可提高棉花产量。

An experimental study of wheat straw mulch in the cotton field

In the northern areas of China with a serious shortage of water resources, how to tap water resources potential and to raise the utilization ratio of crop to water is an important research subject that develops water\|saving agriculture. Spreading wheat straw mulch on the field surface has the advantages of both using local materials and being easily popularized, to which more and more attention is being paid. However, the soil water preservation, water\|saving and yield increase mechanism due to wheat straw mulch has not been understood well as yet. The effects of wheat straw mulch on soil moisture, soil temperature, cotton plant height, cotton boll weight, and the number of boll\|bearing branches of cotton as well as the weight and yield of unginned cotton in the cotton fields were experimentally investigated in 1998. The duration of soil water preservation due to mulching, the variation in daily temperature and the status of cotton growth were analyzed. And the hydrograph of soil moisture was obtained. Field experiments showed that wheat straw mulch could increase soil water, whose effects were mainly exhibited during seedling and boll; the mulch lowered soil temperature in the day, and preserved the temperature in the night; and the mulch could increase boll weight, branch numbers and unginned cotton weight, thus raising cotton yields.