干旱区生态环境知识资源中心(Arid): 不同退化沙地土壤碳的矿化潜力

Arid

	不同退化沙地土壤碳的矿化潜力
其他题名	Carbon mineralization potential in soils under different degraded sandy land
	苏永中; 赵哈林; 张铜会; 赵学勇
来源期刊	生态学报
ISSN	1000-0933
出版年	2004
卷号	24 期号:2 页码:372-378
中文摘要	通过实验室土壤培养试验，研究了科尔沁退化沙质草地不同生境(流动沙地，半固定沙地，固定沙地和丘间低地)下土壤碳的矿化潜力及不同凋落物在沙地土壤中的分解。经33d的室内培养，不同生境土壤CO。一C的释放有极显著的差异，与生境植被盖度，凋落物积累，土壤沙化程度，土壤有机碳和全氮含量的分布有显著相关。流动沙地土壤有极低的土壤有机碳和氮的含量及其微弱的土壤微生物呼吸，表明土地沙漠化不仅导致土壤有机碳库衰竭，也使土壤微生物活性丧失。在有机质含量很低的流动沙地和半固定沙地土壤中，含氮量高的小叶锦鸡儿(Caragana microphylla)凋落物比含氮量低、c／N比高的差巴嘎蒿(Artemisia halodendron)和1年生植物凋落物有较快的分解。在沙漠化的演变中，土壤的粗粒化，有机物质和养分及微生物活性的丧失制约着凋落物在土壤中的矿化潜力。灌木的存在使更多的有机物质和养分积聚在灌丛下，形成灌丛肥岛，因而显著贡献于碳的固存。
英文摘要	The mineralization of soil organic C is an important process regulating the functioning of natural and managed ecosystems. It controls the fluxes of the soil nutrients. In nutrient-poor sandy land ecosystem, the nutrient turnover and the energy transfer between plants and soils depends in large part on the input of litter and its mineralization in the soil. Information on sandy soil C mineralization and its response to a changing environment is therefore required for better understanding of biological feedback of desertification and the mechanism of vegetation restoration in terms of C cycling.In this paper, we measured the potential of organic carbon mineralization in four different sandy habitats (shifting, semifixed, fixed sand dune and interdunal lowland) and the effects of litter addition from shrubs and annual plants on soil microbial respiration using a laboratory soil incubation experiment. Soil samples were collected from two locations; beneath and outside the canopies of shrub in each habitat. Soils were incubated for 33 days with and without litter addition. The results showed that the differences in C mineralization of soils among habitats correlated with the vegetation cover, litter accumulation, and soil structure, organic C and N contents. With the habitat transformation from the fixed sand land to the shifting sand land, 91 percent of soil organic C was lost. Soil microbial respiration in the shifting sand dune was only 8. 6%-’10. 3 % of that in fixed sand dune. This suggested that desertification strongly depleted both bulk of soil organic C and soil labile C pool. Soils amended with Caragana microphylla litter and annual plant litter had the greatest and the lowest microbial respiration, respectively. This might be in part attributed to the N contents and C/N ratios in litters. Caragana microphylla and Artemisia halodendron which distributed widely in Horqin sandy land played an important role not only in fixing mobile sand dune, reducing the intensity and extent of wind erosion, but also in maintaining and improving soil fertility. Shrubs created ’fertile island’ with larger organic C and nutrients and microbial activity under their canopies, and therefore, contributed significantly to C sequestration. to Taitema Nor. in the course of degraded succession of Phragmites communis community, its dominant species was replaced, while Populus euphratica-the dominant species of Populus euphratica community-didn’t change its dominant position in the course of degeneration of its community. As a word, the richness of plant communities were poor little by little in the course of degradation of vegetation in lower reaches of Tarim River, the structure of plant communities simplified gradually due to the limitation of water. The surviving species with strongly drought-enduring ability and the sparseness between species were evident characteristics of degradation of vegetation in the lower reaches of Tarim River.
中文关键词	沙地土壤
英文关键词	lower reaches of the Tarim River
语种	中文
国家	中国
收录类别	CSCD
WOS类目	BIOLOGY
WOS研究方向	Life Sciences & Biomedicine - Other Topics
CSCD记录号	CSCD:1631302
来源机构	中国科学院西北生态环境资源研究院
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/205341
作者单位	中国科学院寒区旱区环境与工程研究所, 兰州, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	苏永中,赵哈林,张铜会,等. 不同退化沙地土壤碳的矿化潜力[J]. 中国科学院西北生态环境资源研究院,2004,24(2):372-378.
APA	苏永中,赵哈林,张铜会,&赵学勇.(2004).不同退化沙地土壤碳的矿化潜力.生态学报,24(2),372-378.
MLA	苏永中,et al."不同退化沙地土壤碳的矿化潜力".生态学报 24.2(2004):372-378.