| Autor: |
Guo JH; College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China., Liu XJ, Zhang Y, Shen JL, Han WX, Zhang WF, Christie P, Goulding KW, Vitousek PM, Zhang FS |
| Jazyk: |
angličtina |
| Zdroj: |
Science (New York, N.Y.) [Science] 2010 Feb 19; Vol. 327 (5968), pp. 1008-10. Date of Electronic Publication: 2010 Feb 11. |
| DOI: |
10.1126/science.1182570 |
| Abstrakt: |
Soil acidification is a major problem in soils of intensive Chinese agricultural systems. We used two nationwide surveys, paired comparisons in numerous individual sites, and several long-term monitoring-field data sets to evaluate changes in soil acidity. Soil pH declined significantly (P < 0.001) from the 1980s to the 2000s in the major Chinese crop-production areas. Processes related to nitrogen cycling released 20 to 221 kilomoles of hydrogen ion (H+) per hectare per year, and base cations uptake contributed a further 15 to 20 kilomoles of H+ per hectare per year to soil acidification in four widespread cropping systems. In comparison, acid deposition (0.4 to 2.0 kilomoles of H+ per hectare per year) made a small contribution to the acidification of agricultural soils across China. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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