Experiences and Research Perspectives on Sustainable Development of Rice-Wheat Cropping Systems in t

来源 :中国农业科学(英文版) | 被引量 : 0次 | 上传用户:a82345678
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
The rice and wheat cropping pattern is one of the main cropping systems in the world.A large number of research results showed that successive cropping of rice and wheat resulted in a series of problems such as hindering nutrition absorption,gradual degeneration of soil fertility,decline of soil organic matter,and increased incidence of diseases and pests.In China,especially in the Chengdu plain where rice-wheat cropping system is practiced,productivity and soil fertility was enhanced and sustained.This paper reviews the relevant data and experiences on rice-wheat cropping in the Chengdu Plain from 1977 to 2006.The principal sustainable strategies used for rice-wheat cropping systems in Chengdu Plain included: 1)creating a favorable environment and viable rotations; 2)balanced fertilization for maintenance of sustainable soil productivity; 3)improvement of crop management for higher efficiency; and 4)use the newest cultivars and cultivation techniques to upgrade the production level.Future research is also discussed in the paper as: 1)the constant topic: a highly productive and efficient rice-wheat cropping system for sustainable growth; 2)the future trend: simplified cultivation techniques for the rice-wheat cropping system; 3)the foundation: basic research for continuous innovation needed for intensive cropping.It is concluded that in the rice-wheat cropping system,a scientific and reasonable tillage/cultivation method can not only avoid the degradation of soil productivity,but also maintain sustainable growth in the long run.
其他文献
很久以来,人们就认识到了隐喻在人类交际和认知活动中的重要作用,隐喻作为一种普遍的语言现象,在各种语言中都有所体现,而情感这一抽象的概念常常是用隐喻来表达的.英汉两种
译作的序言对翻译研究具有重要价值。本文以《简爱》译序为例,从自序与他序、首译与重译、翻译的过程与方法以及译序的角色及作用等方面评述了译序的写法,并且提出了改进的方
以课程为例,结合多年程序设计语言课程的教学实践,分析程序设计语言课程的特点,从教学内容安排的合理性、学生编程兴趣培养、教学方法以及考核方式等方面对自己的教学心得体
根据工程实践,探讨AutoCAD在矿山测量井下巷道标定中的应用,包括CAD在标定巷道开切点、碹岔中线标定中的应用,通过图解即可求得相应坐标、角度及距离的新方法,即将AutoCAD制图技术广泛应用于矿山测量工作中。
自高职出现以来,其公共英语教学复制或沿袭普通高等教育或中职的教学模式,没有从高职教学的实际出发,没有充分考虑就业市场对高职人才英语能力和素质方面的要求.基于此,本文
地层三压力是石油与天然气勘探、开发中非常重要的参数.准确的地层压力剖面预测是钻井设计与施工的基础,是确定合理钻井井身结构、钻井液密度、钻井井控及完井等工艺不可缺少
经典产权理论认为产权清晰是经济发展的前提条件,但是通过产权认知调查,宅基地产权是模糊不清的.基于产权博弈的分析框架,土地产权模糊之下的宅基地开发利用行为出现区域差异
气候类型判别在高中地理教学中意义重大,学生了解了有关气候类型判别的相关图表,有了必要的知识储备,掌握了气候类型的判别的步骤和方法,就能很容易地解决相关问题.
本文对日光温室内光温湿等气象要素变化规律进行了研究,分析了在不同时段、不同天气状况下对温室内温湿变化的影响,结果表明,室内温湿的变化与天空的很多变化因素有关,并且呈
观测员所具备的理论知识较浅薄和自身经验不足,在复杂天气下,分析判断能力较差、目测项目误差较大,直接影响着测报工作.根据一些云状观测记录实例,分析云的观测工作中存在的