[Response of water quality to agricultural cultivation in Liangwanghe River catchment of Fuxianhu Lake region].
Response of water quality to agricultural cultivation was investigated for the Liangwanghe River catchment of Fuxianhu Lake region in Yunnan Province of China. Two typical tillage lands-the rice-wheat rotation (R-W) and the tobacco-pea (T-P) rotation were selected and monitored. Groundwater quality and water quality of Liangwanghe River were monitored simultaneously, as well as the farmland cultivation situation at that time. It was found that cultivation activities, such as transplanting, base fertilizer applying, top dressing, draining would cause apparent elevation of concentrations of TP, PO4(3-)-P, TN, NO3(-)-N and NH4(+)-N of groundwater in a short time period. Nutrients adsorption by crops during different bearing periods has an obvious relationship to the change of contents of TP, PO4(3-)-P, TN, NO3(-)-N, and NH4(+)-N in groundwater in a long time scale. When the crops are in a peak demand for nutrients, contents of nutrients in groundwater were found to reduce obviously, and contents of nutrients may rise for other crop conditions. Contents of TP and PO4(3-)-P of Liangwanghe River for full cultivation periods were found to be 5.8% and 21.7% lower than those for partial cultivation periods, while contents of TN, NH4(+)-N and NO3(-)-N for full cultivation periods were found to be 11.5%, 242.6% and 9.55% higher than those for partial cultivation periods.
Jiang
Hong-kun
HK
Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. jhk20004@yahoo.com.cn
Gao
Hai-ying
HY
Zhang
Qi
Q
Xu
Li-gang
LG
D000383:Agriculture / Q000379:methods; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D005308:Fertilizers; D005618:Fresh Water / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D012275:Oryza / Q000254:growth & development*; D010758:Phosphorus / Q000032:analysis; D045483:Rivers; D014908:Triticum / Q000254:growth & development*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D005308:Fertilizers; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen