| In recent years, as the fertilizer used in agricultural production inputs, N, P and othernutrients inflow to environment which caused by the loss of the seriouspollution. This experiment unifies the country project that is launchin-g a national agricultural pollution census and sichuan agroforestry land of planting charact-eristics, fertilization characteristics, studiesm-ore factors of surface runoff N, P loss regular-ity and tpmultifactor synthetic form and impact. The main research results are as follows:1, The N, P loss degree and erosion form characteristics in sichuan main agricultural cultivated landSichuan main no-till agroforestry N, P surface runoff erosion degree overall is lighter. The middle east hilly area of north and south fertilizer are small, but the middle area (renshou,jianyang,qianwei)slope and paddy fields has appeared in larger N and P loss coefficient, the direction of different points on what the difference is not obvious.80% nitrate nitrogen for dry fields N erosion form, paddy field ammonium and nitrate nitrogen form is not distinct. When the rainfall laedge, P of hilly loss f-orm is mai-nly absorption with sediment, on the other side, when the rianfall sm-all, P ofhilly loss form is mainly soluble form, P loss in paddy field, mainly with soluble form.2, Soil on N, P surface runoff erosion effects.Between different soil types of TN exist very significant difference, but th e TP loss has not significant differences. Violet arenaceous mud, palm purple c lay brown formation of soil type, N, P sur-face runoff erosion differences with mudstone extremely significant for the group, as the palm purple claysoil tha t the N of the surface runoff relative loss erosion degree is the lightest; the br own violet arenaceous mud soil the N relative loss of surface runoff is the lar dgest.3, Slope on N, P surface runoff erosion effects. Along with the increase of slope ran-ge, N surface erosion amount is beco ming larger and larger, but the amount of increase isvery limited, and P surfac e runoff erosion amount and coefficient between 1°and 3°slope there is not obvious diffrence, but its differs with large slope exist significant differences. Monitoring area with slope small (< 5°), medium (5-10°), large(< 15°) increas es, N between small, medium gradient range loss coefficient is not significant differences, but the differences various range between small, medium and large gradient treatments is very significant.4, Rainfall on N, P surface runoff erosion effects.Monitoring area generally produce surface runoff begins in April and ends i n September, in July reaches the peak; rainfall r-unoff is far greater than the nu mber of times each treatment produced runoff, the number of times of rainfall i n scale to all 50%. Runoff with rainfall increasing increases, both is very signifi cant positive correlation, the correlation coefficient reached 0.8136.During heavy rains N and P surface runoff accounted for the totalarea of annual runoff table 75%.5, Fertilization on N, P surface runoff erosion effects.With increased fertilizer fertilization increased, optimization and increasing N fertilization treatment more than potato fertilizer treatments the N loss increa se. Paddy fields and slope farmland that use organic fertilizer processing produ ct-ion flow has different rate decreases, and N, P loss extent lighter. Different kinds of fertilizer has the influence of forms of N, P loss.6, Farming management on N, P surface runoff erosion effects.Different farming treatment the potato-fertilizer+down slope processing (724.0 L) whose runoff is the largest, the optimization fertilizer+protective cul-tivation (cross-sectional slope precision+straw mantle+alley cropping) (568.3L) is smallest, compare with the down slope processing cross-sectional average runoff reduced 9.8%. The slope of N and P loss planting and loss coefficients are the largest. There is no significant differences between treatments In the P. 7, Quantifiable factors on N, P surface runoff erosion.whether in the research of the slope or wet soil, quantifiable factors and N and P loss of surface runoff amount and loss coefficient has a significantly linear relation, the correlation coefficient are more than 0.8. Rainfall in N, P s urface runoff erosion played a big role. Compeared rianfall, the influence of fe rtilizer on surface runoff and erosion certain small, but its exist positive correla tion; The common of fertilizer and rainfall has opposite bi-gger effect on N an d P loss. The slope has little impact on its, and mainly for direct connect func tion. |
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