【作者】 王延好；

【导师】 张肇鲲； 陈瑛；

【作者基本信息】 安徽农业大学 ， 农业机械化工程， 2005， 硕士

【摘要】 免耕耕作就是在前茬作物收割完毕后在留茬地上直接进行下一茬作物的播种。 深松耕作有助于作物根部穿透发育,从而改善作物的出苗数。 在粘土土壤中深松耕作还可以改善土壤结构。 免耕耕作体系从19世纪60年代开始到目前已经得到快速的完善并在世界范围内广泛推广。据加拿大 1997 年统计显示,当时传统耕作占 69%,保护性耕作占 24%,免耕只占 7%。然而今天,免耕耕作经过最近几年许多农民的大量实践,其好处已经为农民所认可。采用免耕耕作可以保持土壤水分,提高作物产量,减少劳动力,节约能耗;而且还可以有利于种子发芽和苗期生长。与传统耕作相比免耕耕作可以减少机械作业量,获得更好的土壤环境益于作物的生长发育。 综上所述,免耕耕作确实具有许多优点,但是另一方面免耕耕作技术目前还存在一定的缺陷,比如机械化的田间耕作造成的对土壤的压实问题,特别是在粘土的情况下,就是影响免耕耕作技术推广的最大障碍。 本文的主要研究目标就是采用不同的耕作方式(深松耕作、传统耕作和免耕耕作)对作物进行耕作,然后来研究作物的生长状况,土壤压实以及作物产量。 研究结果显示,深松耕作确实可以减轻土壤压实状况,在春季雨水多时,可以减少表层土壤的水分,增加作物的出苗发芽速度,提高作物产量,但是深松耕作需要拖拉机能耗大成本高,所以深松耕作只是在需要的时候才使用。 免耕耕作具有如下优点: 免耕耕作有益于作物秸秆还田,由于上季作物的残茬可以减少冬季的风速,减少土壤水分流失从而免耕耕作具有较高的土壤水分。免耕耕作具有均匀合适的播种深度。免耕耕作出苗速度比传统耕作好,而且可以增产增效。 相比之下免耕耕作成本小,益于机械作业,采用免耕耕作技术,可以节省时间和劳动力,节约能源,增产增效,同时还可以保持土壤水分。而且通过免耕还可以控制冬季的风蚀、水蚀,增加土壤养分,改善土壤的生物生存环境。所以免耕耕作是一种非常可行的耕作技术。但是免耕耕作的效益需要进行长期连续耕作才能明显表现出来。更多还原

【Abstract】 No-tillage is defined as seeding directly into previously undisturbed soil. The use of the sub-soiler did improve the maximum root penetration, crop emergence, and plant population. The sub-soiling is also effective to improve soil structure and plant in heavy clay soils No-tillage cropping systems and concepts have evolved rapidly since the early 1960s and are practicing worldwide. According to statistics Canada (1997), conventional tillage is practiced on 69% of Canada’s total arable land, followed by conservation tillage 24% and No-tillage 7%. Today, the benefits of no-tillage have been confirmed by recently years of continuous no-tillage cropping on numerous farms. Under this system, moisture is conserved, yield are improved, labour is minimized, and fuel consumption is reduced. It also had the similar speed of emergence and plant population. Furthermore no-tillage system requires less machinery inventory and it can also result in the similar or better soil properties and plant performance as compared with the conventional tillage. Previous discussion illustrated that no-tillage has many advantages; however, due to existing hardpan in soil from previous tillage practices as well as time required to condition the soil is a major obstacle to switch to no-tillage systems, especially in clay soil. The objectives of the paper were to investigate the effects of different tillage(sub-soiling tillage, conventional tillage and no-tillage)practices on: soil compaction, plant performance, and crop yields. The results showed that ST can reduce the soil compaction, decreased the topsoil moisture content in spring,increase the crop emergence, improved the yield. However, sub-soiling requires a high tractor power and high cost, one may perform sub-soiling only when it needs. While under the no-tillage systems, it has the advantage as following: No-tillage is beneficial for the straw incorporation on soil productivity. Standing stubble could reduce wind velocity in winter, which reduces the amount of drying. Therefore, greater standing straw results in higher soil moisture content of NT treatment. No-tillage has appropriate seeding depth and its uniformity also very good. No-tillage has very good crop emergence and higher crop yield than conventional tillage. Considering its low cost and comparative performance, no-tillage is a feasible tillage alternative and can be practiced in a heavy clay soil. Under the no-tillage system, time and labor is minimized, fuel consumption is reduced, yields are improved, and soil moisture is conserved. Furthermore, no-tillage has many other advantages such as controlling wind and water erosion, increasing soil organic matter and promoting biological activities in soil. However, the long-term benefit can not be achieved if producers see the system works in a short term更多还原