喀斯特地区不同年限桂牧1号象草草地土壤养分特征  

Soil nutrients properties of differently aged pastures of Pennisetum purpureum cv. Guimu-1 in the Karst region

作　　者：胡培雷 曾昭霞[1,2] 王克林[1,2] 宋希娟[1,2] 李莎莎[1,2,3] 

机构地区：[1]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,湖南长沙410125 [2]中国科学院环江喀斯特生态系统观测研究站,广西环江547100 [3]中国科学院大学,北京100049

出　　处：《草业科学》2016年第1期1-10,共10页Pratacultural Science

基　　金：中国科学院科技服务网络计划(STS计划)"广西喀斯特区生态服务提升与民生改善研究示范(KFJ-EW-STS-092)";国家自然科学基金(41471445)

摘　　要：人为干扰和管理措施对喀斯特地区生态恢复影响显著。本研究以典型喀斯特地区种植1年(1-y G)、5年(5-y G)和7年(7-y G)的桂牧1号杂交象草(Pennisetum purpureum cv.Guimu-1)栽培草地为研究对象,以玉米(Zea mays)种植地(CK)作为对照,分析不同建植年限下栽培草地对地上部分生物量、土壤养分含量及微生物量碳的影响。结果表明,1)建植年限对桂牧1号草地地上部分生物量影响显著(P<0.05),表现为7-y G<1-y G<5-y G。2)桂牧1号草地0-50cm土层土壤N、P、K随建植年限呈现先下降后升高的趋势,建植5年的牧草地土壤N、P、K养分含量普遍较低;土壤有机碳含量在各土层均以建植7年草地最高,5年草地最低。土壤表层(0-10 cm)微生物生物量碳表现为1-y G<5-y G<7-y G,且7年草地分别比1年和5年草地增加了32.37%和19.18%。3)桂牧1号草地土壤有机碳、全氮、全磷、全钾含量及土壤表层微生物生物量碳均高于相应土层玉米地,而碱解氮、速效磷和速效钾含量则刚好相反。因此,相比玉米农耕地,桂牧1号栽培草地能有效提高喀斯特地区土壤肥力,其中,以建植7年的草地固碳效果最好,"种草养畜"是喀斯特地区生态恢复与重建的有效措施。Human disturbance and management approaches contribute significantly to ecological restoration of Karst region. This study is to determine the effects of different planting years of Guimu-1（ Pennisetum purpureum cv. Guimu-1）on aboveground biomass,soil nutrients,and soil microbial biomass carbon by comparing the three pastures sites [1-year（ 1-y G）,5-year（ 5-y G） and 7-year-old（ 7-y G） Guimu-1 planting years] and corn field（ Zea mays,CK） in the Karst region. The results of this study showed that the aboveground biomass of Guimu-1 were significantly different among planting years（ P〈0. 05） and was in order as 7-y G 〈1-y G 〈5-y G. The soil nitrogen（ N）,phosphorus（ P）and potassium（ K） in the soil profiles（ 0-50 cm） decreased firstly and then increased with the increase of the planting years,indicating that they were the lowest in the 5-y G pasture; The soil organic carbon content in each soil layer（ 0-50 cm） were the highest in the 7-y G pasture,and it was the lowest in the 5-y G pasture. The soil microbial biomass carbon（ MBC） in top soil（ 0-10 cm） were in the order of 1-y G 〈5-y G〈 7-y G,and the MBC in 7-y G pasture increased the 32. 37% and 19. 18% when compared to 1-y G and 5-y G pasture,respectively. Soil organic carbon,total nitrogen,total phosphorus,total potassium at different soil depths and MBC in the top soil were higher in Guimu-1 pastures than those in the corn field with the corresponding soil layers,and soil available nitrogen,available phosphorus and available showed an opposite trend. This study implied that the Guimu-1 pasture enhanced the soil fertility significantly,and the soil carbon sequestration potential was the best in the 7-y G pasture. The implementation of planting grass for raising livestock possibly can be used as an effective restoration and rehabilitation approach in the Karst region.

关 键 词：喀斯特地区 桂牧1号 土壤养分 土壤有机碳 土壤微生物生物量碳 

分 类 号：S812.2[农业科学—草业科学]