Effects of Different Tillage Systems on Soil Properties,Root Growth,Grain Yield,and Water Use Efficiency of Winter Wheat (Triticum aestivum L.) in Arid Northwest China

Studies on root development, soil physical properties, grain yield, and water-use efficiency are important for identifying suitable soil management practices for sustainable crop production. A field experiment was conducted from 2006 through 2008 in arid northwestern China to determine the effects of four tillage systems on soil properties, root development, water-use efficiency, and grain yield of winter wheat （Triticum aestivum L.）. The cultivar Fan 13 was grown under four tillage systems：conventional tillage （CT） without wheat stubble, no-tillage without wheat stubble mulching （NT）, no-tillage with wheat stubble standing （NTSS）, and no-tillage with wheat stubble mulching （NTS）. The soil bulk density （BD） under CT system increased gradually from sowing to harvest, but that in NT, NTSS, and NTS systems had little change. Compared to the CT system, the NTSS and NTS systems improved total soil water storage （0-150 cm） by 6.1-9.6 and 10.5- 15.3% before sowing, and by 2.2-8.9 and 13.0-15.1% after harvest, respectively. The NTSS and NTS systems also increased mean dry root weight density （DRWD） as compared to CT system. The NTS system significantly improved water-use efficiency by 17.2-17.5% and crop yield by 15.6-16.8%, and the NTSS system improved that by 7.8-9.6 and 7.0-12.8%, respectively, compared with the CT system. Our results suggested that Chinese farmers should consider adopting conservation tillage practices in arid northwestern China because of benefits to soil bulk density, water storage, root system, and winter wheat yield.

Benefits of Conservation Agriculture on Soil and Water Conservation and Its Progress in China

Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture （CA） is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world＇s arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture.

Effect of Limited Single Irrigation on Yield of Winter Wheat and Spring Maize Relay Intercropping

一个场地实验在收割冬小麦(Triticum aestivum ) 和春天玉米(Zea mays ) 的季节评估有限单身者的效果的 2002/2003 期间被进行在接力赛在西北的中国的一个半干旱的区域杂种下面在收益和两庄稼的水使用上滴灌溉。A 控制了 35 公里单身者灌溉，早或迟了，在某个生长阶段被用于每庄稼。土壤水，叶面积，最后的谷物收益和产量构成因素象千谷物的重量那样，一些尖铁，肥沃的小穗状花小穗数，每尖铁谷物数，并且粒重每尖铁被测量，并且水使用效率和叶面积指数被计算为灌溉并且非灌溉的接力赛杂种处理和唯一的收割控制。结果在杂种的继电器显示出那收益，产量构成因素，水使用效率，和叶面积指数处理被有限单身者影响在小麦和玉米的各种各样的生长阶段期间滴灌溉。处理在小麦和标题的出发阶段和玉米的开花期舞台期间灌溉了的在杂种的继电器的全部的收益在所有处理之中是最高的，由在小麦的开花期阶段和玉米的 silking 舞台期间灌溉了那列在后面；那么是水使用效率。重要差别发生在大多数产量构成因素在之间灌溉并且非灌溉的杂种继电器的处理。在杂种继电器或完全收割的小麦和玉米的叶面积指数的动力学显示出单个山峰的模式的一种类型，而杂种的继电器，处理显示出双山峰的一种类型模式。适当地，有限单个灌溉和控制土壤水分含量水平能导致更高全部的产量，水使用效率，和叶面积指数，并且在接力赛杂种改进产量构成因素。这个惯例节省了为灌溉使用并且也增加了收益的水的数量。因此，小麦和标题的标题舞台和玉米的开花期舞台被建议是最佳在半干旱的区域的杂种继电器的小麦和玉米的有限单个灌溉时间。

Integrated water resources management for sustainable development of in western rural China

Management in water resources development of Jinghe watershed of western rural China is examined with Participatory Rural Appraisal method--a rare applied method in China and questionnaire survey of stakeholders. Combination of these two survey methods derives good results as it could avoid personal bias in identifying and ranking the issues on a concrete basis in following up households' survey. Statistic Package for Social Sciences (SPSS) was used for data analysis. Results indicate that since the early 1980s, issues of water scarcity, river pollution, soil erosion, insufficient participation of stakeholders in water resources use and management, as well as centralized water planning and management system have created difficulties for sustainable development of the watershed. The stakeholders and local governments are fully aware of the challenges and are committed to achieving a solution through integrated water resource management (IWRD). The concept and the application of IWRD for rural China are reviewed and analyzed, and a framework for implementation of IWRD in China is developed. It is concluded that the keys to successful implementation of the approach will depend on optimal arrangement of institutions, policy reforms, community involvement and capacity building in water sector, which need to fully integrate various management functions within the watershed.