草业学报2017，Vol.26Issue(12)：236-242,7.DOI:10.11686/cyxb2017070
不同恢复措施对宁夏典型草原土壤碳氮储量的影响
Effects of different restoration measures on storage of soil organic carbon and nitrogen in typical steppe of the Loess Hilly Area in Ningxia
摘要
Abstract
Land-use strongly influences soil properties such as soil organic carbon (SOC) and total nitrogen (TN).This study has been done to investigate changes in grassland organic carbon and nitrogen storage characteristics under different restoration measures in typical steppe of the Loess Hilly area in Ningxia,which is located in the Yunwu hills (longitude 106°21'-106°27' E,latitude 36°10'-36°17' N,altitude 1800-2100 m) and has a very steep slope (approx.30-50°).The annual mean temperature is 5 ℃,with a range from approx.22-25 ℃ in summer (July) to-14 ℃ in winter (January).The annual precipitation is 445 mm,of which 60 ％ occurs in autumn and is associated with storm events in the July-September period that sometimes cause runoff.The storage of organic carbon and nitrogen was measured in 0-10,10-20,20-30 and 30-40 cm soil layers for three different restoration measures,including grazed (control),exclosure,contour trenches and fish-scale pits.Our results revealed that the content of SOC and TN were the highest in exclosure grassland (30.35 and 2.92 g/kg respectively),followed by grazed,fish-scale pits and contour trenches (P＜0.05).C/N was highest in exclosure grassland,in the middle in contour trenches and fish-scale pits,and the lowest in grazed grassland.The content of SOC and TN under the different restoration measures decreased with increasing soil depth except for the content of TN of 10-20 cm soil layer in contour trenches and fish-scale pits.However,soil depth did not have an effect on soil bulk density under the different measures.The density of SOC and TN was highest in exclosure and grazed grassland,in the middle in fish-scale pits and the lowest in contour trenches.Soil depth had an effect on the density of SOC under different restoration measures whereas it had no effect on the density of TN.The storage of both soil carbon and nitrogen decreased in the following order:exclosure＞grazed＞fish-scale pits＞contour trenches.Organic carbon storage was highly significantly positively correlated with soil organic carbon and total nitrogen content;and nitrogen storage was significantly positively correlated with total nitrogen content.关键词
恢复措施/典型草原/土壤碳氮含量/碳氮密度/碳氮储量Key words
restoration measure/typical steppe/content of soil organic carbon and total nitrogen/density of soil organic carbon and total nitrogen/storage of soil organic carbon and total nitrogen引用本文复制引用
周瑶,马红彬,贾希洋,张蕊,宿婷婷,周静静,吴兴旺..不同恢复措施对宁夏典型草原土壤碳氮储量的影响[J].草业学报,2017,26(12):236-242,7.基金项目
国家自然科学基金项目(31460632,31360582)和中国科学院“西部之光”人才培养引进计划项目(XAB2015A10)资助. （31460632,31360582）
