鸡桑药共生模式库区土壤养分变化及流失风险  

Soil nutrient dynamics and loss risks in a chicken-forage mulberry-medicinal plant intercropping system

作　　者：赵丽平[1] 杨贵明[2] 赵同科[1] 马茂亭[1] 刘宝存[1] 肖长坤 杨明宇 安志装[1] 

机构地区：[1]北京市农林科学院植物营养与资源研究所,北京100097 [2]承德医学院蚕业研究所,承德市067000 [3]北京市密云县农业技术推广站,北京101500

出　　处：《生态学报》2012年第12期3737-3744,共8页Acta Ecologica Sinica

基　　金：国家科技支撑计划(2012BAD15B01);北京市科技计划(D101105046410003)

摘　　要：密云水库是北京市主要地表水源地,为了有效防控水源保护区坡耕地以氮磷流失为主的农业面源污染,开展污染防控植物篱种植区散养和单独喂养油鸡试验研究;采集两种模式区土壤和散养模式区饲用桑植物样品,测定氮磷钾养分含量,分析土壤养分变化规律及其流失风险,建立经济有效种养生态防控模式。结果表明,与对照相比,两种油鸡养殖模式区土壤有机质、全氮、速效氮磷钾及硝态氮含量都呈显著或极显著性地升高,促进了散养共生模式区饲用桑和药用植物的生长,增加了对土壤养分的吸收;受养殖密度的影响,60只/666.7m2高密度油鸡喂养模式区或散养集中活动区有机质、全氮、全磷含量显著高于散养活动较少低密度区;受地表径流的影响,散养共生模式区坡下部油鸡少活动区域土壤速效氮磷钾含量与上部活动较多区域相比分别升高20.3%、71.9%和21.9%。喂养模式区承载粪便氮磷环境负荷分别为189 kg/hm2和84.8 kg/hm2,超过欧盟农田氮限量标准170 kg/hm2和粪便年施磷限量80 kg/hm2,具有较大的流失污染风险;20只/666.7m2低密度散养模式区承载粪便氮磷负荷分别为75.6 kg/hm2和33.9 kg/hm2,远小于环境限量标准,具有较小的流失污染风险。饲用桑与药用植物间作植物篱种植区散养油鸡排泄粪便矿化分解提供了植物养分资源,促进它们的生长,形成发达根系系统又可有效阻截模式产生有机物和氮磷流失,同时该模式提供了散养油鸡饲料资源。以上结果说明,桑树/药用植物/低密度散养油鸡是一种有效的农业面源污染生态防控共生模式,资源循环利用效率高,生态环境和经济效益好。Miyun Reservoir is the main source of drinking water for Beijing.However,it is increasingly threatened by losses of nitrogen and phosphorus from slope farmland in the drinking water source protection catchment.A contour hedgerow intercropping system of forage mulberry（Morus multicaulis Perr.） and medicinal plant was planted to control and mitigate the non-point source contaminants in the catchment.Free-range Beijing Fatty Chickens were raised in the intercropping areas（free-range mode） to feed on mulberry additives in the adjacent areas（feeding mode）.Topsoil samples from the two modes were collected for determination of organic matter,nitrogen,phosphorus and potassium contents,and mulberry samples from the free-range mode and its control were collected for determination of nitrogen（N）,phosphorus（P） and potassium（K） contents in the plant.The results showed that compared with the controls,the soil organic matter content（OM）,total nitrogen（TN）,available N,P and K,and nitrate of the two mode areas increased significantly,which promoted the growth of the mulberry and medicinal plant and the nutrient uptake;the soil organic matter,TN and total phosphorus（TP） were greater in the feeding and free-range mode with high density of 60 and low density of 20 chickens per mu,respectively,than those in the free-range mode.However,compared with the upper parts of the slope farmland in the free-range chickens with high density,the soil available N,P and K at the lower parts of the slope farmland were increased by 20.3%,71.9% and 21.9%,respectively.It suggests that the soil nutrient accumulation could be related to the feeding density and runoff.The nitrogen and phosphorus loads from chicken manure in the feeding mode were 189kg/hm2 and 84.8kg/hm2,respectively,which exceeded the EU（European Union） limits of 170kg N/hm2 and 80kg P2O5/ hm2,respectively;it could lead to high N and P losses to the Reservoir.The N and P loads in the free-range mode were 75.6kg/hm2 and 33.9kg/hm2,respectively,much

关 键 词：坡耕地 种养模式 防控 农业面源污染 

分 类 号：S158[农业科学—土壤学]