土表覆盖水稻秸秆对大棚水蕹菜产量和土壤肥力的影响

Effect of Rice Straw Surficial Mulch on Soil Fertility and Yield of Water Spinach in Plastic Tunnel

在大棚内采用塑料栽培箱种植水蕹菜,并在土表覆盖水稻秸秆,研究土表覆盖水稻秸秆对土壤表层溶液和土壤理化性质、秸秆腐解率、蕹菜产量的影响。结果表明:春茬和夏茬蕹菜土表覆盖水稻秸秆后土壤表层溶液电导率呈先上升后下降最后趋缓的变化趋势,氧化还原电位呈先下降后上升最后趋缓的变化趋势。春茬和夏茬蕹菜栽培3个月后,水稻秸秆腐解率分别为75.33%和89.11%。两个茬口覆盖秸秆处理的蕹菜前期产量均较低,后期显著提高,总产量分别显著增加13.54%和11.37%。春茬覆盖秸秆处理的土壤有机质、全氮、全钾含量较对照显著增加15.55%、11.81%和12.89%,硝态氮含量显著降低19.31%;夏茬覆盖秸杆处理的土壤有机质、全钾含量较对照显著增加12.44%、11.71%,硝态氮含量显著降低25.13%。春茬和夏茬覆盖秸秆处理的土壤脲酶、酸性磷酸酶活性和蔗糖酶活性均较对照提高,且高温夏季淹水环境对土壤酶活性的抑制作用更明显。

In this experiment,spinach(Ipomoea aquatica Forsk)was planted in plastic box under plastictunnel,and rice straw was laid on soil surface.The aim of this experiment was to study the effect of covering soilsurface by rice straw on surface soil solution,soil physicochemical property,stem decomposition rate and yield ofwater spinach.The results showed that the conductivity of soil solution showed a changing trend of firstly rising,then decreasing,and finally slowing down both in spring and summer cultivation.The redox potential showed atrend of firstly decreasing then rising and finally slowed down.The decomposition rate of rice straw were75.33%and89.11%,respectively after3months of spring and summer cultivation.The yields of water spinach with rice straw laying on soil surface were both lower in the earlier stage,and rose significantly at later period.The totalyield increased13.54%and11.36%,respectively.In spring cultivation,the contents of soil organic matter,total N and total K increased15.55%,11.81%and12.89%,respectively than that of the contrast.The content ofnitrate nitrogen decreased19.31%.In summer cultivation,the contents of soil organic matter,total K increased12.44%and11.71%,than that of the contrast,while the content of nitrate nitrogen decreased25.13%.In springcultivation with rice straw covering on soil surface,the activities of soil urease and phosphatase increased33.16%and8.76%than that of the contrust.And in summer cultivation,the activity of soil sucrase increased23.15%than that of the contrast.