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为合理开发利用冷浆稻田提供科学依据,从1989~1991年设置起垄栽培与普通栽培对比试验,小区面积为500m~2,重复4次。三年的试验结果表明,起垄栽培利于改善冷浆地水、气、热状况,增加土壤通气透水性,总孔隙度和耕层土温。促进土壤速效养分的释放供应,促使水稻根系活力,增加水稻有效分蘖和干物质含量,确保稻谷结实率和安全成熟,其增产率达6.8%~12.3%。可为进一步开发利用延边地区和北方寒冷地区冷浆稻田提供行之有效的方法。 相似文献
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讨论了测定土壤总孔隙度的有关简易方法失误渊源的辩正,论证了水稻土的地貌分类以及由此引出的一些问题。 相似文献
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喷灌和畦灌对冬小麦农田表层土壤结构的影响 总被引:3,自引:0,他引:3
A two-year experiment was carried out on the effect of sprinkler irrigation on the topsoil structure in a winter wheat field. A border-irrigated field was used as the control group. The total soil porosity, pore size distribution, pore shape distribution, soil cracks and soil compaction were measured. The sprinkler irrigation brought significant changes to the total soil porosity, capillary porosity, air-filled porosity and pore shape of topsoil layers in comparison with the border irrigation. The total porosity and air-filled porosity of the topsoil in the sprinkler irrigation were higher than those in the border irrigation. The changes in the air-filled and elongated pores were the main reasons for the changes in total porosity. The porosities of round and irregular pores in topsoil under sprinkler irrigation were lower than those under border irrigation. Sprinkler irrigation produced smaller soil cracks than border irrigation did, so sprinkler irrigation may restrain the development of macropore flow in comparison with border irrigation. The topsoil was looser under sprinkler irrigation than under border irrigation. According to the conditions of topsoil structure, it is preferable for crops to grow under sprinkler irrigation than under border irrigation. 相似文献
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在人工草地上,分别测定了威提特东非狼尾草、纳罗克非洲狗尾草、海法白三叶的茎叶、枯落物及根系生物量,同时测定了三种草茎叶、枯落物持水保水能力;并以祼地和耕地为对照,以土壤容重、孔隙度、有机质为指标对三种牧草的土壤改良能力进行了评价.结果表明:非洲狗尾草茎叶生物量(干重)为11.92t/hm2,显著高于东非狼尾草及海法白三叶,东非狼尾草为9.66t/hm2,显著高于海法白三叶(7.35t/hm2).根系生物量,非洲狗尾草与东非狼尾草差异不显著,但显著高于白三叶;茎叶最大持水量,非洲狗尾草显著高于东非狼尾草及白三叶,东非狼尾草显著高于白三叶;茎叶生物量亦同.枯落物量,非洲狗尾草为5.85 t/hm2,显著高于东非狼尾草及白三叶.非洲狗尾草枯落物对水分的有效截留量为18.26t/hm2,显著高于东非狼尾草及白三叶,东非狼尾草及白三叶之间无显著差异.从土壤容重、总孔隙度和土壤有机质测定结果可知,草地土壤结构较为稳定,种植牧草后土壤肥力得到显著改善. 相似文献
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