【作者】 杜娟；

【导师】 赵明；

【作者基本信息】 中国农业大学 ， 种植业， 2005， 硕士

【摘要】 为了探讨保护性耕作在解决我国北方旱区农业生产中存在的效益低、环境恶化、沙尘暴频发、农田土壤风蚀沙化等一系列制约区域经济和社会发展的问题中的实际作用,通过对该区域的典型保护性耕作技术试验区有关保护性耕作的技术效果及其问题与对策进行了调查和研究,并取得了以下结果: 1、保护性耕作具有多重技术效果:(1)在风蚀防治方面,通过对沙地、草地、传统翻耕农田和保护性耕作农田等不同地表覆盖<0.05mm悬移质颗粒分析表明,传统翻耕农田占30.87%,保护性耕作占28.36%,草地占18.99%,沙地占0.62%。保护性耕作的农田土壤风蚀减少在14%~88%之间,进一步明确了裸露农田和退化草原是沙尘暴沙尘的重要来源;(2)在土壤生态改善方面的研究表明,保护性耕作农田土壤水分增加,表层土壤温度降低,土壤养分状况改善。这些结果进一步证明保护性耕作对土壤生态有正负不同效应,但总体效应更有利于农田生态保护和作物生长;(3)在增产方面的研究表明,保护性耕作条件下我国北方的几种主要作物都表现出不同程度的增产效果。其中增幅最高达24.19%(籽瓜),玉米平均增产8.2%,最低也有5%(小麦),也有个别地区由于技术实施问题表现减产。在保护耕作中,深松玉米可增产28.41%;免耕可增产14.97%;(4)保护性耕作条件下几种主要作物都表现出不同程度的节本增效效果,其中尤以经济作物节本增效的优势突出。啤酒大麦其节本高达70～110元/亩,增收达84.54元/亩;从而进一步明确了保护性耕作在粮食增产、农民节本增效上均具有显著的效果。 2、保护性耕作在我国北方旱区存在着一系列制约其发展的问题,技术问题主要表现在:(1)技术体系发展不完善,其对策是利用农机与农艺的配套来打破传统的种植方式:(2)土壤低温问题,其对策是利用品种选择和深松等生物、生态和农艺措施进行有益补偿;(3)杂草控制问题,其对策主要是利用生物和化学以及农艺措施的综合方法来防治消灭杂草蔓延。认识问题主要表现在对保护性耕作认识不足和理解偏面,其解决的对策是加强宣传和获得政府的大力支持。政策问题主要表现政策与外部环境没有根本的改观,其解决的对策是需要国家和各级政府制定相应的鼓励和扶植政策,多途径的投入,对推广工作进行组织和督导。更多还原

【Abstract】 In northern arid area of China there are many problems which have restricted the development of economy and society such as environmental deterioration, frequently occurred dust storm, cropland soil wind erosion and lower agricultural productivity. In order to study the effects of conservation tillage on resolving these problems, the economic, social and ecological benefit of conservation tillage in the 24 test regions in the North of China have been investigated. The results were as follows: 1. Multi effects were found in conservation tillage: (1) Conservation tillage can prevent soil wind erosion. The suspension transport granules (dia.<0.05mm) percentage in tibba, grassland, fields with traditional and conservation tillage were 0.62%, 18.99%, 30.87%, 28.76%, respectively. The conservation tillage can reduce soil wind erosion to 14-88% in different conditions. It confirmed that the uncovered cropland and degenerate grassland are the source of the dust storm. (2) Studies on soil characters showed that soil water content and nutrition status increased and surface layer temperature decreased. It indicated that conservation tillage had positive and negative effects on soil economy, but the total effects were in favor of cropland economy conservation and crop growth. (3) Yield of main crops in north China were improved in conservation tillage condition. Thereinto the amplitude of melon is the biggest (24.19%) while the amplitude of wheat is the smallest (5%); Different types of maize under conservation tillage usually got higher yield than those under conventional tillage and the amplitude is 8.2% in average. Under conservation tillage, the deep- plough gained a 28.41% yield improvement and no-till 14.97%. (4) Various degrees of costs saving and benefits increasing were showed in conservation tillage in several crops, especially in economic crops. For example malting barley under conservation tillage can save costs with 70~110yuan/666.7m~2 and increase benefits with 84.54yuan/666.7m~2. To sum up, conservation tillage can evidently improve the yield of crops, save costs and increase benefit.2, There are a lot of problems which limited development of conservational tillage in northern arid area of China. The technical problems showed that: First, technical system was unperfected, and the countermeasure is to take advantage of agriculture technical be break the tradition cultivate form; Second, the soil temperature was low, and the countermeasure is to select appropriate cultivars and employ deep plough to compensate it; Third, weeds controlling were difficult, and the countermeasure is to use integrative methods of biological, chemical and agronomical ways to prevent and cure the weed spread. Propagandizing and government sustaining are the must to cope with the cognition problems on conservation tillage. The policy problems were that rudimentary changes were not occurred in policy and conditions, government must take charge of the project, establish an integrative service system of research, education, spreading, and promote the application and spreading of conservational tillage technologies.更多还原