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Agricultural land use and management practices may affect soil properties,which play a critical role in sustaining crop production.Since the late 1970s,several new agricultural land use types had been introduced in the rural areas of China.The purpose of this study is to evaluate the effect of these land use changes on the soil properties,nu-trient absorption rate,and nutrient use economic efficiency ratio in an agricultural area of Beijing.Specifically,the cropland,the orchard and the vegetable field were examined.Results of this study suggest that land use and farming management practices significantly affect the content of soil organic carbon (SOC),total nitrogen (TN),total phos-phorus (TP),and available phosphorus in the surface layer of 0-25 cm (p<0.05) in the Yanqing Basin,northwestern Beijing.Soil nutrients in each agricultural land use type decrease rapidly with the increasing soil depth.Orchard and vegetable field tend to have higher soil nutrients than the cropland does.However,the soil nutrient-absorption rate (NAR) of the orchard and vegetable field is lower than that of the cropland,even though orchard and vegetable field may provide much higher economic benefit.While increasing SOC,TN,and TP in the orchard and vegetable field by intensive farming may be a valuable option to improve soil quality,potential increase in the risk of nutrient loss,or agricultural non-point source pollution can be a tradeoff if the intensive practices are not managed appropriately.
The land use and management practices may affect soil properties, which play a critical role in sustaining crop production. Since new years land use types had been introduced in the rural areas of China. The purpose of this study is to evaluate the effect of these land use changes on the soil properties, nu-trient absorption rate, and nutrient use economic efficiency ratio in an agricultural area of Beijing. Specifically, the cropland, the orchard and the vegetable field were examined. Results of this study suggest suggest that land use and farming management practices significantly affect the content of soil organic carbon (SOC), total nitrogen (TN), total phos-phorus (TP), and available phosphorus in the surface layer of 0-25 cm in the Yanqing Basin, northwestern Beijing.Soil nutrients in each agricultural land use type decreasing rapidly with the increasing soil depth. Orchard and vegetable field tend to have higher soil nutrients than the cropland does .Howev er, the soil nutrient-absorption rate (NAR) of the orchard and vegetable field is lower than that of the cropland, even though orchard and vegetable field may provide higher economic benefit. vegetable field by intensive farming may be a valuable option to improve soil quality, potential increase in the risk of nutrient loss, or agricultural non-point source pollution can be a tradeoff if the intensive practices are not managed appropriately.