کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10997850 1332079 2017 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Using a nitrogen-phosphorus ratio to identify phosphorus risk factors and their spatial heterogeneity in an intensive agricultural area
ترجمه فارسی عنوان
با استفاده از نسبت نیتروژن-فسفر به شناسایی عوامل خطر فسفر و ناهمگنی فضایی آنها در یک منطقه کشاورزی فشرده
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
چکیده انگلیسی
High phosphorus risk in intensive agricultural regions, which threatens an increasing number of water bodies within the regions, is driven by the nitrogen-phosphorus ratio (N:P ratio). The mechanism remains unclear, however. Most nutrient studies are based on local-scale field trials, which failed to identify the geographical factors that drive phosphorus accumulation at the larger scale of a watershed. To address this issue, we adopted a large-scale, remote-sensing-driven model to simulate the N:P ratio in the soil of the Sanjiang Plain, one of the most important commercial grain bases of China. A grid-random sampling method was employed to test the validity of the model. The results show that 35% of the higher N:P ratios were converted to lower ratios in old cultivated land where the concentration of soil phosphorus increased by 1-2 times over 11 years (2000-2010); however, in the new cropland cultivated from forestland, grassland and wetland, 18% of the lower N:P ratios were converted to higher ratios, with soil phosphorus concentration increased slightly. Higher N:P ratios come from greater nitrogen input into the new cropland soil, which reduces soil pH and then enhances phosphorus accumulation, thus increasing the phosphorus risk. We find that the variation in land-use types and the excessive input of anthropogenic fertilizers are the two dominant factors influencing the N:P ratio. Intensive anthropologic activities changed traditional knowledge on the relationship between the N:P ratio and phosphorus accumulation, and further necessitated large-scale research on nutrients in intensive agricultural regions. The finding can shed new light on phosphorus management and non-point source pollution control in intensive agricultural areas.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: CATENA - Volume 149, Part 1, February 2017, Pages 426-436
نویسندگان
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