一項(xiàng)研究發(fā)現(xiàn),，植物不會(huì)全部吸收施到土壤中的氮基合成化肥,，該研究發(fā)現(xiàn)剩余的化肥可能對(duì)周圍環(huán)境產(chǎn)生至少80年的影響。
Mathieu Sebilo及其同事通過同位素“標(biāo)記”化肥使其留下可探測(cè)的特征,，從而研究了硝酸鹽化肥的長(zhǎng)期命運(yùn),。這些化肥于1982年被施在了法國(guó)的一塊農(nóng)田中，種植者在這里輪番種植糖用甜菜和冬小麥,。在施肥之后30年,，
這組作者報(bào)告說，這些作物吸收了所施化肥的至多61%-65%,，而12%到15%的化肥仍然殘留在土壤有機(jī)質(zhì)中,。殘留的化肥的大部分已經(jīng)向地下水泄漏。這組作者預(yù)測(cè),，這些化肥將在該地的環(huán)境中至少留存另外50年,。由于氮可能污染飲用水源以及淡水和沿海生態(tài)系統(tǒng)，它在土壤中的存在引起了擔(dān)憂,。
這組作者指出,，由于人口增長(zhǎng)和對(duì)食品的需求，在許多地區(qū),，來自合成化肥的氮如今超過了天然的氮的含量,。這組作者說，當(dāng)試圖減少水的農(nóng)業(yè)硝酸鹽污染的時(shí)候,，過去施用合成化肥的長(zhǎng)期遺產(chǎn)必須被考慮進(jìn)去,。（生物谷Bioon.com）
生物谷推薦的英文摘要
Proceedings of the National Academy of the Sciences of the United States of America doi: 10.1073/pnas.1305372110
Long-term fate of nitrate fertilizer in agricultural soils
Mathieu Sebiloa，1,， Bernhard Mayerb,， Bernard Nicolardotc，
Pinayd,， and André Mariottia
Increasing diffuse nitrate loading of surface waters and groundwater has emerged as a major problem in many agricultural areas of the world,， resulting in contamination of drinking water resources in aquifers as well as eutrophication of freshwaters and coastal marine ecosystems. Although empirical correlations between application rates of N fertilizers to agricultural soils and nitrate contamination of adjacent hydrological systems have been demonstrated， the transit times of fertilizer N in the pedosphere–hydrosphere system are poorly understood. We investigated the fate of isotopically labeled nitrogen fertilizers in a three–decade-long in situ tracer experiment that quantified not only fertilizer N uptake by plants and retention in soils,， but also determined to which extent and over which time periods fertilizer N stored in soil organic matter is rereleased for either uptake in crops or export into the hydrosphere. We found that 61–65% of the applied fertilizers N were taken up by plants， whereas 12–15% of the labeled fertilizer N were still residing in the soil organic matter more than a quarter century after tracer application. Between 8–12% of the applied fertilizer had leaked toward the hydrosphere during the 30-y observation period. We predict that additional exports of 15N-labeled nitrate from the tracer application in 1982 toward the hydrosphere will continue for at least another five decades. Therefore,， attempts to reduce agricultural nitrate contamination of aquatic systems must consider the long-term legacy of past applications of synthetic fertilizers in agricultural systems and the nitrogen retention capacity of agricultural soils.
