共查询到17条相似文献,搜索用时 91 毫秒
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不同除草剂对土壤养分的影响 总被引:1,自引:0,他引:1
除草剂在杀死杂草的同时对土壤微生物群落和数量也起到一定作用,由于土壤微生物的变化而引起土壤养分的变化,本实验通过不同除草剂对土壤养分的影响探讨选择,即能起到除草作用对土壤养分影响又小的除草剂类型和剂量。 相似文献
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药肥处理对老参地土壤微生物区系及化学性质的影响 总被引:1,自引:0,他引:1
采用棉隆和多菌灵结合拌施有机肥处理技术对老参地进行改造,研究了药肥处理对老参地土壤微生物区系及化学性质的影响。结果表明:老参地经过棉隆和多菌灵拌肥处理后,土壤中真菌数量分别下降24%和27%,细菌数量分别增加15.09%和24.52%,放线菌数量分别增加8.84%和31.54%;土壤p H分别提高4.18%和7.57%,有机质含量分别增加5.09%和5.72%,速效氮含量分别增加28.36%和3.67%,速效磷含量分别增加51.13%和16.87%。通径分析结果表明,药肥处理主要通过增加老参地土壤中速效磷含量来降低土壤中真菌数量,通过增加有机质含量来增加细菌及放线菌数量。综上,药肥处理可以改善老参地的土壤微生物区系及土壤化学性质,从而可能减轻人参轮作障碍的发生。 相似文献
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乌鲁木齐县蔬菜地土壤养分空间变异研究 总被引:4,自引:0,他引:4
以乌鲁木齐县蔬菜主产区的三个乡为例,采用GIS与地统计学相结合的方法对其耕层土壤(0~20 cm)的有机质、全氮、速效氮、速效磷、速效钾等5种养分要素的空间变异特征进行分析.结果表明:全氮变异函数曲线的理论模型能很好地符合球状模型;有机质、碱解氮、速效磷、速效钾的变异函数曲线则符合线性无基台模型.有机质、速效磷和速效钾具有很强的空间相关性,说明受母质、地形、土壤类型等自然的结构性因素影响较大;碱解氮具有中等的空间相关性,说明对施肥、作物、管理水平等随机因素引起的空间相关性起很大作用;全氮的空间相关性很弱,说明人为活动严重削弱了结构性因素造成强的自相关作用. 相似文献
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烤烟连作对重庆土壤养分状况的影响 总被引:4,自引:0,他引:4
通过田间取样和室内分析相结合的方法,调查研究了重庆市石柱、奉节和南川3个县烤烟连作土壤的养分状况。结果表明:烟田连作后土壤pH值下降,相邻茬次之间平均下降0.05,土壤酸化;有机质含量逐年下降,相邻茬次之间平均衰减0.56%g/kg;全氮、全磷、全钾含量随连作年限延长表现出不同程度的升高趋势,表现为P(6%~31%)>K(6%~21%)>N(2%~12%);速效磷、速效钾含量随连作年限延长逐年降低,且降低程度P(6%~24%)>K(2%~10%),速效氮含量略有上升;速效养分N/P、N/K和K/P比值明显增加,土壤养分比例失调。 相似文献
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[Objective] This experiment aimed to investigate the effects of continuous cropping of Panax notoginseng on the properties of rhizosphere soil. [Method] A total of 12 rhizospheres oil samples were collected in the fields continuously cropped with P. notoginseng for different years and the soil properties including pH value, contents of available N, available K, available P,total N, total K, total P and organic matter were determined. [Result] With the increase in the number of years of continuous cropping, seven soli indices: soil pH value, organic matter content, total N, total P, total K, available P and available K gradually increased, while available N showed a gradual downward trend. The contents of organic matter content, total N, total P, total K,available P, available K and available N after three years of continuous cropping were increased by 74.93%, 65.85%, 123.82%,18.78%, 341.67%, 120.16% and -32.16%, respectively, indicating that continuous cropping of P. notoginseng resulted in nutrient enrichment in rhizosphere soils. The pH value and available N in IBC (soil inside the border check) and UBC (soil under the border check) were higher than that in BBC (soil beside the border check), suggesting that the soil was gradually alkalized due to the continuous cropping of P. notoginseng. [Conclusion] These results suggest that pH change and nutrient imbalance may be the obstacles to the continuous cropping of P. notoginseng. 相似文献
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