| 摘要: |
| 以春玉米品种沈玉17为材料,设置保护性耕作(NT)、传统耕作＋秸秆还田(TS)和传统耕作(CT)3种耕作方式,通过多年定位试验,研究黄土高原旱塬地保护性耕作农田土壤有机质及团聚体特性的变化。结果表明,NT与TS和CT相比能显著提高土壤有机质含量。干筛法分析结果表明, 0~30 cm深度,NT处理粒径>0.25 mm的大团聚体含量、平均重量直径(mean weight diameter,MWD)均显著高于TS和CT处理。湿筛法分析结果表明,水稳性团聚体MWD在0~10 cm深度为NT>TS>CT,处理间差异显著(P<0.05);0~20 cm深度,NT处理土壤团聚体破坏率均低于CT处理。保护性耕作能促进土壤团聚体的形成,提高团聚体的稳定性,而传统耕作则由于人为扰乱土层结构,降低了土壤团聚体数量和稳定性。 |
| 关键词: 黄土高原 保护性耕作 有机质 团聚体 平均重量直径 |
| DOI：10.11841/j.issn.1007-4333.2011.04.012 |
| 投稿时间：2010-10-20 |
| 基金项目:农业部先正达农业科教及农村发展项目; 公益性行业(农业)科研专项经费资助(200903007) |
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| Effects of conservation tillage on soil aggregatesin dry land of loess plateau |
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ZHAO Ru-lang1, FENG Bai-li1, JIANG Shu-huai1, ZHANG Xiao-dong1, QU Yang1, CAI Xiao-qing2, ZHU Rui-xiang3
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| (1.College of Agronomy,Northwest A & F University,Yangling 712100,China;2.Agricultural Mechanism Bureau,Huangling 727300,China;3.College of Mechanical and Electronic Engineering,Northwest A&F University,Yangling 712100,China) |
| Abstract: |
| The paper studied the effects of conservation tillage on the soil aggegate and organic carbon by years on Loess Plateau.The spring maize cultivars Shenyu17 were used in the test under three farming modes of No tillage (NT),conventional tillage＋Straw returning (TS) and conventional tillage (CT).To study the effects,soil organic matter content was measured,and the aggregates composition,size distribution were examined by dry and wet sieving methods.The results showed that,NT significantly increased soil organic matter content compared with TS and CT.Dry sieving results showed that NT was higher in macro-aggregate content (R＞0.25) and mean weight diameter(MWD) than other treatments at 0-30 cm.Wet sieving results showed that the MWD of water-stable aggregates showed the trend:NT＞TS＞CT at 0-10 cm,Their differences reached the significant level of P<0.05 among the three tillage treatments.At 0~20cm,Destruction rate of aggregate under NT was higher than CT.NT increased the aggregation and the stability of soil aggregates,while due to intense disturbance,the aggregation and stability were decreased under CT. |
| Key words: loess plateau conservation tillage organic carbon soil aggregate MWD |
