Journal article
Impacts of cropping systems on soil nitrogen storage and loss
Department of Renewable Resources, University of Louisiana at Lafayette, Lafayette, LA 70504, USA1
Department of Land, Air, and Water Resources, University of California, Davis, CA 95616, USA2
Department of Vegetable Crops, University of California, Davis, CA 95616, USA3
Department of Agronomy and Range Science, University of California, Davis, CA 95616, USA4
Organic and low-input cropping systems that use more C inputs are alternatives to conventional systems for sustaining long-term soil fertility. An understanding of the impacts of these cropping systems on N balance (N applied minus N removed in harvested plant material), storage and loss is necessary to improve long-term soil fertility and minimize the risk of environmental pollution.
An evaluation of 4-year rotations of organic (N from legumes and composted manures), low-input (N from legumes and reduced amounts of synthetic fertilizers), and conventional (conv-4, N from synthetic fertilizers) and a conventional 2-year rotation (conv-2, N from synthetic fertilizers) on N balance, storage and loss was conducted from 1989 to 1998.
Compared to the conv-2 system, the organic and conv-4 systems showed 119 and 8% greater cumulative N balances, respectively, over the duration of the study. However, N balance in the low-input system was 19% less than in conv-2 system. After 10 years of differential management, total N in the top 15 cm of soil was 1.46 g kg−1 in the organic, 1.26 g kg−1 in the low-input, 1.13 g kg−1 in the conv-4, and 1.1 g kg−1 in the conv-2 system.
Compared to the conv-2 system, cumulative N losses for the organic, low-input and conv-4 systems were lower by 80, 92, and 10%, respectively. These findings suggest that organic and low-input cropping systems that add C to soil have the potential for storing N and making it available for future crop use, while minimizing the risk of environmental pollution.
Language: | English |
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Year: | 2000 |
Pages: | 253-268 |
ISSN: | 18732267 and 0308521x |
Types: | Journal article |
DOI: | 10.1016/S0308-521X(01)00011-7 |