Zhang Ming-Kui, Wang Yang, Huang Chao
Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, College of Natural Resource and Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
Ying Yong Sheng Tai Xue Bao. 2011 Dec;22(12):3211-20.
By the method of site-specific observation, and selecting 27 field plots with 7 planting patterns in Shaoxing county of Zhejiang Province as test objects, this paper studied the characteristics of nitrogen (N) and phosphorous (P) runoff losses, loads, and their affecting factors in the croplands with different planting patterns in riverine plain area of the Province under natural rainfall. The mean annual runoff loads of total P, dissolved P, and particulate P from the field plots were 4.75, 0.74 and 4.01 kg x hm(-2), respectively, and the load of particulate P was much higher than that of dissolved P. The mean annual runoff loads of total N, dissolved total N, dissolved organic N, NH4(+)-N, and NO3(-)-N were 21.87, 17.19, 0.61, 3.63 and 12.95 kg x hm(-2), respectively, and the load of different fractions of dissolved total N was in the sequence of NO3(-)-N > NH4(+)-N > dissolved organic N. As for the field plots with different planting patterns, the runoff loads of total N, dissolved total N, dissolved organic N, and NO3(-)-N were in the sequence of fallow land < nursery land < single late rice field < double rice field < rape (or wheat)-single late rice field < wheat-early rice-late rice field < vegetable field, while those of total P and particulate P were in the sequence of fallow land < nursery land < single late rice field and double rice field < wheat-early rice-late rice field < rape (wheat)-single late rice field < vegetable field. No significant difference was observed in the load of water-dissolved P among the test plots with different planting patterns. The runoff losses of N and P mainly occurred in crop growth period, and the proportions of N and P losses in the growth period increased with increasing multiple crop index. The runoff losses of total N, dissolved N, and NO3(-)-N were mainly related to the application rate of N fertilizer, and soil NO3(-)-N content also had obvious effects on the runoff losses of total N and dissolved N. The runoff loss of dissolved organic N was related not only to N application rate, but also to soil total N and organic carbon. The runoff loss of NH4(+)-N was mainly related to soil available NH4(+)-N, but not related to N application rate. The runoff losses of total P and particulate P were related to both P application rate and soil available P, while the runoff loss of water dissolved P was less related to P application rate but had relations to soil total P and available P.
通过定点观测方法，选取浙江省绍兴县7种种植模式的27个田块作为试验对象，研究了该省河网平原区不同种植模式农田在自然降雨条件下氮（N）、磷（P）径流流失特征、负荷及其影响因素。试验田总磷、溶解态磷和颗粒态磷的年均径流负荷分别为4.75、0.74和4.01 kg·hm⁻²，颗粒态磷负荷远高于溶解态磷。总氮、溶解态总氮、溶解态有机氮、NH₄⁺-N和NO₃⁻-N的年均径流负荷分别为21.87、17.19、0.61、3.63和12.95 kg·hm⁻²，溶解态总氮各组分负荷顺序为NO₃⁻-N＞NH₄⁺-N＞溶解态有机氮。不同种植模式田块中，总氮、溶解态总氮、溶解态有机氮和NO₃⁻-N的径流负荷顺序为：休耕地＜苗圃地＜单季晚稻田＜双季稻田＜油菜（或小麦）-单季晚稻田＜小麦-早稻-晚稻田＜菜地，而总磷和颗粒态磷的径流负荷顺序为：休耕地＜苗圃地＜单季晚稻田和双季稻田＜小麦-早稻-晚稻田＜油菜（小麦）-单季晚稻田＜菜地。不同种植模式试验小区间水溶态磷负荷差异不显著。氮、磷径流流失主要发生在作物生长季，且氮、磷流失比例随复种指数增加而增大。总氮、溶解态氮和NO₃⁻-N的径流流失主要与氮肥施用量有关，土壤NO₃⁻-N含量对总氮和溶解态氮的径流流失也有明显影响。溶解态有机氮的径流流失不仅与施氮量有关，还与土壤全氮和有机碳有关。NH₄⁺-N的径流流失主要与土壤有效NH₄⁺-N有关，与施氮量无关。总磷和颗粒态磷的径流流失与施磷量和土壤有效磷均有关，而水溶态磷的径流流失与施磷量关系较小，但与土壤全磷和有效磷有关。
