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几种常用除草剂在美国加州水田环境中的归宿
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作者 王一茹 《农业环境保护》 CSCD 1990年第3期40-44,共5页
本文综合了近年来的研究成果,对几种常用除草剂在美国加里福尼亚州水田环境中的归宿加以论述。其中重要的迁移、降解过程是挥发、光亲核取代反应、光氧化以及喷雾过程中的漂移。这些过程的研究有助于预测农药在水田中的归宿和改变农药... 本文综合了近年来的研究成果,对几种常用除草剂在美国加里福尼亚州水田环境中的归宿加以论述。其中重要的迁移、降解过程是挥发、光亲核取代反应、光氧化以及喷雾过程中的漂移。这些过程的研究有助于预测农药在水田中的归宿和改变农药的性质以达到高效、安全、无害的目的。 展开更多
关键词 除草剂 水田环境 美国加州
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水田环境下水稻直播机自动驾驶控制方法 被引量:6
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作者 张雁 李彦明 +3 位作者 刘翔鹏 陶建峰 刘成良 李瑞川 《农业机械学报》 EI CAS CSCD 北大核心 2018年第11期15-22,共8页
为了解决无人化水稻直播机在水田里作业时精度不高的问题,提出了一种在不平整泥泞水田环境中的水稻直播机自动驾驶控制方法。首先建立了水稻直播机的运动学模型,基于横向偏差和航向角偏差,提出了一种用于直线作业段的非线性转向控制算... 为了解决无人化水稻直播机在水田里作业时精度不高的问题,提出了一种在不平整泥泞水田环境中的水稻直播机自动驾驶控制方法。首先建立了水稻直播机的运动学模型,基于横向偏差和航向角偏差,提出了一种用于直线作业段的非线性转向控制算法。为了避免水田路面不平坦对定位系统的影响,通过倾角传感器获取车身姿态,修正定位误差。通过检测计算位置与地边的相对距离,实现了地头自动转弯。水田实验结果表明,所提控制方法的路径跟踪平均横向绝对偏差为0. 027 m,具有较好的跟踪精度和稳定性,且自动转弯算法切实有效,提供了一种在水田环境下可行的自动驾驶控制方法。 展开更多
关键词 水稻直播机 水田环境 自动驾驶 控制方法
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日本典型水田生态环境保护协会分类及其比较分析
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作者 代小平 陈菁 +1 位作者 杨文海 陈丹 《三峡大学学报(自然科学版)》 CAS 2013年第1期6-11,共6页
环境保护协会是农村生态环境保护的重要力量.日本环保协会在水田生态环境保护中发挥了重要的作用,积累了丰富的经验.研究日本水田生态环境保护协会发展经验对建设我国农村环保协会,改善我国农村生态环境具有重要的意义.在实地调研的基础... 环境保护协会是农村生态环境保护的重要力量.日本环保协会在水田生态环境保护中发挥了重要的作用,积累了丰富的经验.研究日本水田生态环境保护协会发展经验对建设我国农村环保协会,改善我国农村生态环境具有重要的意义.在实地调研的基础上,以日本枥木县西鬼怒地方环境改善协会和鲣鱼会为例,对日本典型水田生态环境保护组织的活动内容、组织结构、财务收支和监督管理状况进行了总结,分析了协会发展的成效、经验及存在的问题.构建了生态环境保护协会的分类方法,对日本的典型水田生态环境保护组织进行了分类.结果表明,日本典型水田生态环境保护组织主要为自治型. 展开更多
关键词 日本 水田生态环境保护 协会 分类
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日本典型水田生态环境保护协会状况及启示 被引量:1
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作者 匡益兵 代小平 张晓红 《东北水利水电》 2011年第6期69-70,共2页
文章以日本枥木县西鬼怒地方环境改善协会为例,对日本正式环保组织的活动内容、组织结构、财务收支和监督管理状况进行剖析,分析了协会发展的经验及存在的问题。
关键词 日本 水田生态环境保护 协会
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Technology of groundwater reservoir construction in goafs of shallow coalfields 被引量:13
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作者 MA Li-qiang ZHANG Dong-sheng +2 位作者 LI Xiang FAN Gang-wei ZHAO Yong-feng 《Mining Science and Technology》 EI CAS 2009年第6期730-735,共6页
In exploiting shallow coal resources in western China, conservation of water resources is often subjugated to considerations of safety and production in coal mines. In order to maintain a sustainable development in th... In exploiting shallow coal resources in western China, conservation of water resources is often subjugated to considerations of safety and production in coal mines. In order to maintain a sustainable development in the Shenfu-Dongsheng coalfield, we propose a technology of constructing groundwater reservoirs in goafs in shallow coalfields to protect fragile ecological environments. Given the premise of safe production, we selected an appropriate goaf as the site for constructing a groundwater reservoir and used a mine water recharge technique in combination with other related techniques for effective water conservation. Then filtering and purification techniques were used to purify the mine water given the physical and chemical properties of mine water and its filling material, ,thereby greatly reducing suspended matter, calcium and other harmful ions in the water. With the potential of widely application, the research result has been successfully applied in the Daliuta coal mine, to great economic and ecological effect. Therefore, this achievement provides a new way for mine water conservation in shallow coal resources in western China. 展开更多
关键词 shallow coalfields groundwater reservoir GOAF PURIFICATION storage protection
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A discussion of the risks and benefits of using rock terracing to limit soil erosion in Guizhou Province
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作者 杰克.麦孔其 马焕成 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期41-47,83,共7页
The construction of stone terraces to minimise soil erosion is common throughout Guizhou. This technique, however, has high inherent risk. Stone terraces are usually much higher than those with earth risers. While th... The construction of stone terraces to minimise soil erosion is common throughout Guizhou. This technique, however, has high inherent risk. Stone terraces are usually much higher than those with earth risers. While they trap a greater thickness of soil on the slope they increase the risk of slope failures, reduce moisture and nutrient availability to plants, and thin more soil up slope. The stone risers also threaten long-term productivity. When a riser collapses debris is deposited over the terrace below making farming difficult. These breaches in the terrace focus surface runoff leading to gully formation and increased sediment transport down slope. Artificial drainage systems, often used in conjunction with terracing, compound the risk. These channels prevent precipitation from soaking into the soil. This limits groundwater and soil moisture recharge which reduces the availability of water for crops and the length of the growing season. The rapid drainage of water from the slope reduces the time of concentration of the catchment resulting in an increase in flood activity. Floods are caused by smaller rainstorm events. They arrive faster and peak quicker and higher than before the channels were constructed. Engineering solutions to soil erosion must therefore be used in conjunction with, and are not as a substitute for, good land management strategies. Furthermore, despite changes in land use practices, and the application of new technologies, there is a maximum amount of production that can be obtained from this land on a sustainable basis. 展开更多
关键词 Soil erosion Reafforestation TERRACING Sustainability LANDSLIDING Environmental management
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