期刊
JOURNAL OF ENVIRONMENTAL QUALITY
卷 50, 期 3, 页码 627-638出版社
WILEY
DOI: 10.1002/jeq2.20215
关键词
-
资金
- Purdue Agricultural Research Programs
- USDA National Institute of Food and Agriculture [87887]
The study shows that different drain spacings can affect drainflow and nitrate-N losses, while nitrate-N concentrations remain relatively constant under different drain spacings. Annual nitrate-N loads are linearly correlated with annual flow volumes, indicating relatively stable nitrate concentrations.
Subsurface drainage is an essential water management practice for many poorly drained soils in the U.S. Midwest, but this practice also contributes nitrate-N loads to surface waters. This paper summarizes results from Years 16-31 of a long-term drainage research project in southeastern Indiana and compares results with the first 15 yr of the study. The study compared three drain spacings (5, 10, and 20 m) managed with a no-till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation, with cover crops in about half of the years. Drainflow and nitrate-N losses per unit area were greatest for the 5-m spacing and lowest for the 20-m spacing. Nitrate-N concentrations did not vary with drain spacing and were generally in the range of 4-9 mg L-1. Annual nitrate-N loads were linearly correlated with annual flow volumes, reflecting the relatively constant concentrations over the 16-yr period. Whereas nitrate-N concentrations were relatively constant throughout the year, short-term concentration spikes occurred for nitrate-N during June-July of corn years. About 70% of annual drainflow and N loads occurred during the fallow season of November-April. The results underscore the interacting effects of drainage design, crop management, and weather in determining the magnitude of N loss from drained agricultural fields.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据