Quantifying the Effect of Soil Moisture on the Aerobic Microbial Mineralization of Selected Pesticides in Different Soils
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- 作者：Reiner Schroll ; Hans Heinrich Becher ; Ulrike Dö ; rfler ; Sebastian Gayler ; Sabine Grundmann ; Hans Peter Hartmann ; and Jü ; rgen Ruoss
- 刊名：Environmental Science & Technology
- 出版年：2006
- 出版时间：May 15, 2006
- 年：2006
- 卷：40
- 期：10
- 页码：3305 - 3312
- 全文大小：261K
- 年卷期：v.40,no.10(May 15, 2006)
- ISSN：1520-5851
文摘
A standardized quantitative approach was developed toreliably elucidate the effect of increasing soil moisture onpesticide mineralization. The mineralization of threeaerobically degradable and chemically different 14C-labeled pesticides (isoproturon, benazolin-ethyl, andglyphosate) was studied under controlled conditions inthe laboratory at an identical soil density of 1.3 g cm-3. Theagricultural soils used are characterized by (i) largevariations in soil texture (sand content 4-88%) and organicmatter content (0.97-2.70% org. C), (ii) fairly diverse soil-water retention curves, and (iii) differing pH values. Wequantified the effect of soil moisture on mineralization ofpesticides and found that (i) at soil water potential 
-20MPa minimal pesticide mineralization occurred; (ii) alinear correlation (P < 0.0001) exists between increasingsoil moisture (within a soil water potential range of -20 and-0.015 MPa), and increased relative pesticide mineralization;(iii) optimum pesticide mineralization was obtained at asoil water potential of -0.015 MPa, and (iv) when soil moistureapproximated water holding capacity, pesticide mineralization was considerably reduced. As both selected pesticidesand soils varied to a large degree, we propose that thecorrelation observed in this study may be also valid in thecase of aerobic degradation of other native and artificialorganic compounds in soils.
-20MPa minimal pesticide mineralization occurred; (ii) alinear correlation (P < 0.0001) exists between increasingsoil moisture (within a soil water potential range of -20 and-0.015 MPa), and increased relative pesticide mineralization;(iii) optimum pesticide mineralization was obtained at asoil water potential of -0.015 MPa, and (iv) when soil moistureapproximated water holding capacity, pesticide mineralization was considerably reduced. As both selected pesticidesand soils varied to a large degree, we propose that thecorrelation observed in this study may be also valid in thecase of aerobic degradation of other native and artificialorganic compounds in soils.