The effect of agriculture on water environment in a subtropical island

亚热带岛屿农业对水环境的影响

• 批准号: 20780179
• 负责人: YOSHINAGA Ikuo
• 金额: $ 2.75万
• 依托单位: National Agricultural Research Organization
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2008
• 资助国家: 日本
• 起止时间: 2008 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20780179/
• 关键词: 水質汚濁; 水環境

The purpose of this study was to analyze the effect of agriculture on water environment in a water-starved subtropical island. Most irrigation ponds were categorized as in eutrophic states and water blooms were observed. It is suggested that runoff from livestock is the main nutrient source. Rainfall runoff from farmland had few eutrophying effects on inflowing loads, because the runoff mainly consisted of roadway discharge and so relevant concentrations were low. Nitrate nitrogen concentrations of groundwater were high, assuming that the nitrate contamination originated from fertilizer and manure. The values and trends of nitrate concentrations at monitoring wells varied greatly. These results imply horizontal groundwater flow is not uniformly distributed and the each well gathers water from vicinal area. It was estimated that around 22% nitrogen output from human activity leached to the groundwater.

本研究的目的是分析农业对水环境的影响，在一个缺水的亚热带岛屿。大多数灌溉池塘被归类为富营养化状态，观察到水华。牲畜排泄径流是主要的营养源。农田降雨径流主要以巷道径流为主，相关浓度较低，对入流负荷的富营养化影响较小。地下水中硝酸盐氮浓度较高，假定硝酸盐污染来源于肥料和粪便。监测威尔斯各井硝酸盐浓度值及变化趋势差异较大。这些结果表明，地下水流水平分布不均匀，各井均从邻近区域取水。据估计，人类活动产生的约22%的氮排放到地下水中。

项目成果

伊江島のため池の水質環境と降雨時の流入負荷

伊江岛水库水质环境及降雨期间入水负荷

• 发表时间: 2008
• 作者: 吉永育生;住秀和;小笠原敬;原口暢朗;生駒泰基
• 通讯作者: 生駒泰基

Water quality environment of ponds and groundwater in subtropical island

亚热带海岛池塘及地下水水质环境

• 发表时间: 2008
• 作者: YOSHINAGA Ikuo;SUMI Hidekazu;KUBOTA Tomijiro;HARAGUCHI Noburo;IKOMA Hiroki
• 通讯作者: IKOMA Hiroki

琉球石灰岩地域における地下水の硝酸態窒素濃度

琉球石灰岩地区地下水硝态氮浓度

• 发表时间: 2009
• 作者: 吉永育生;住秀和;原口暢朗;生駒泰基
• 通讯作者: 生駒泰基

亜熱帯離島におけるため池と地下水の水質環境

亚热带偏远海岛水库及地下水水质环境

• 发表时间: 2008
• 作者: 吉永育生;住秀和;久保田富次郎;原口暢朗;生駒泰基
• 通讯作者: 生駒泰基

Nitrate contamination of groundwater in a limestone Island

石灰岩岛地下水的硝酸盐污染

• 发表时间: 2009
• 作者: YOSHINAGA Ikuo;SUMI Hidekazu;HAMADA Koji;SHIMA Takeo;IKOMA Hiroki
• 通讯作者: IKOMA Hiroki