Soil Physical Characteristics as Influenced by Conservation Tillage under An Intensive Cropping System
Conservation tillage is a viable technique for sustainable agricultural development in the North China Plain. Yet few studies exist on the influences of conservation tillage practices on soil properties and processes. The objective of this study was to investigate changes of soil physical properties as related to the shift from conventional moldboard plow to conservation tillage systems based on a long-term field experiment. The study, initiated in 2001, included three tillage treatments for winter wheat, moldboard plow (CT), rotary tillage (RT), and not- till (ZT). In 2005, soil organic matter (OM) content, bulk density, aggregate distribution and stability, and water retention curves were measured after harvesting winter wheat, and soil saturated hydraulic conductivity (Ks) was determined after harvesting corn. The results indicated that comparing to the CT, soil OM contents under the ZT treatment were increased significantly in the 0-30cm layer, and as a result, soil physical properties were improved. On the other hand, RT influences on soil OM and physical properties were limited within the 0-10cm layer. Overall, the conservation tillage systems increased soil OM content, the contents of macro-aggregates (> 0.25mm) and water-stable aggregates, available water content, and saturated hydraulic conductivity. Nevertheless, soil bulk density increase and saturated hydraulic conductivity decrease was observed in the 0-5cm layer under ZT, and in the 5-10 cm layer under RT. Soil physical quality evaluation using the S theory showed that the ZT and RT treatment had higher S values, and therefore better soil physical quality, than the CT treatment. Although the S value was an effective soil quality indicator, it may not be able to reflect the connectivity of soil pores. A combined application of S value and Ks was recommended.
Conservation tillage soil physical property water retention curve S value
Du Zhangliu Zhou Hu Ren Tusheng Lu Yizhong
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094
国际会议
2006年中—加保护性耕作论坛(China-Canada Conservation Agriculture Forum)
北京
英文
113-123
2006-09-21（万方平台首次上网日期，不代表论文的发表时间）