農業肥料污染水源 這筆帳算出來了! | 環境資訊中心
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農業肥料污染水源 這筆帳算出來了!

2008年12月01日
摘譯自2008年11月24日ENS美國,曼哈頓報導;潘忠廷編譯;莫聞審校

堪薩斯州的河流。圖片來源:美國地調局堪薩斯科學中心據美國堪薩斯大學(Kansas State University)最新研究指出,因為水源受農業肥料污染,政府當局、飲用水處理廠房以及每個美國人,每年為此的支出總和至少43億美元。負責此研究的生物學教授杜德斯(Walter Dodds)表示,研究者已計算出為了保護水中生物免於受到營養物的污染,一年得投入4400萬美元。

杜德斯與堪薩斯大學的研究者得出上述結論,主要是依據美國環保署的全美水體氮、磷含量資料庫。

氮、磷等破壞性物質,是以非點源污染為主,經由湖泊或是從單一管線進入環境的,相對來說是少數。杜德斯指出,這些物質以各種方式進入環境,例如:行栽作物(row crop)透過逕流影響周邊土地。

研究者已計算出污染造成的金錢損失,影響因素有湖邊土地減值、處理飲用水支出以及愈來愈少人從事釣魚與划船等休閒娛樂造成稅收減少。

杜德斯期望這份經堪薩斯大學的調查能夠被決策者採用,因為報告忠實記錄了美國營養物污染問題,並呈現出事情的重要性。他說到:「把環境問題用金錢損失來呈現,決策者與大眾就會注意到。以金錢來衡量環境問題,人們才去算計污染所造成的實際花費。」

本項研究已刊登於上月出版的《環境科學與科技》(Environmental Science and Technology)期刊網路版。

造成氮磷污染有下列幾項原因: 

  • 過度施肥,住宅區以及農業區皆是。
  • 雨水逕流經過農地、動物飼養場與牧場,將動物排泄物帶到水體中。
  • 雨水流經欠缺雨水管理的市區與郊區,例如:停車場、草坪、屋頂以及道路。
  • 污水處理廠排放之氮、磷物質。
  • 化糞池溢出水。
More Than Health Damaged by Ag Nutrients in Drinking Water
MANHATTAN, Kansas, November 24, 2008 (ENS)

The pollution of fresh water by agricultural nutrients costs government agencies, drinking water facilities and individual Americans at least $4.3 billion a year in total, finds new research from Kansas State University.
Biology professor Walter Dodds, who led the study, says the researchers calculated that $44 million a year is spent just protecting aquatic species from nutrient pollution.

Dodds and the K-State researchers based their conclusions on U.S. Environmental Protection Agency data on nitrogen and phosphorous levels in bodies of water throughout the country.

The damaging chemicals - phosphorous and nitrogen - enter the environment from nonpoint sources rather than flowing into a lake or stream from one pipe.

They enter the water from various points, such as runoff from row crop agriculture across the surrounding lands, said Dodd.

The researchers calculated the money lost from that pollution by looking at factors like decreasing lakefront property values, the cost of treating drinking water and the revenue lost when fewer people take part in recreational activities like fishing or boating.

Dodds said he anticipates the K-State research will be used by policymakers because it documents the extent of the nutrient pollution problem in the United States and one facet of why it matters.

"Monetary damages put environmental problems in terms that make policymakers and the public take notice," he said. "Putting environmental problems in terms of dollars allows people to account for the actual costs of pollution."

The study appears in the November 12 online issue of the journal "Environmental Science and Technology."

Contributors to nitrogen and phosphorus pollution include:

• Overusing fertilizer - both residential and agricultural usage
• Rainfall flowing over cropland, Animal Feeding Operations and pastures, picking up animal waste and depositing it in water bodies
• Rainfall flowing over urban and suburban areas where stormwater management is not required, such as parking lots, lawns, rooftops, roads
• Discharge of nitrogen and phosphorus from wastewater treatment plants
• Overflow from septic systems