Taking Nitraria tangutorum Bobr. sandpiles in desert?riverside ecotone on north edge of Ordos Plateau as research objects, morphological characteristics(including height, radius, surface area, volume,and dry weight of soil),dry weight per plant(including dry weights of above?and under?ground parts per plant and total dry weight per plant)of N. tangutorum, and soil carbon storage of different development types(including growth, mature and decline types)of N. tangutorum sandpiles were calculated and compared by standard plant estimation method, and relationships among these indexes were analyzed. The results show that morphological characteristics, dry weight per plant of N. tangutorum,and soil carbon storage of mature sandpile are significantly(P<0.05)higher than those of growth and decline sandpiles. Moreover, except dry weight of above?ground part per plant of N. tangutorum,above indexes of growth sandpile are lower than those of decline sandpile. According to estimation,total carbon storage of N.tangutorum plants in the plot is 429.123 kg,that of soil is 445.415 kg,and the latter is 1.038 times the former. The result of fitting curve analysis shows that there is a positive correlation of dry weight per plant of N. tangutorum with different morphological characteristics of sandpile,and its correlation with sandpile volume is the highest;there is also a positive correlation of soil carbon storage with different morphological characteristics of sandpile, and its correlations with sandpile volume and dry weight of soil are the highest. The correlation of dry weight per plant of N. tangutorum with soil carbon storage in mature sandpile is higher than that in growth and decline sandpiles, and correlation of dry weight of under?ground part per plant of N. tangutorum with soil carbon storage in different development types of sandpiles is higher than that of dry weight of above?ground part per plant and total dry weight per plant of N. tangutorum with soil carbon storage. It is suggested that N. tangutorum sandpiles in desert?riverside ecotone can fix a lot of carbon, in which, carbon sequestration capacity of mature sandpile is the strongest. Moreover, N. tangutorum roots play an important role in fixing carbon in soil.%以鄂尔多斯高原北缘的沙漠-河岸过渡带唐古特白刺(Nitraria tangutorum Bobr.)沙堆为研究对象,采用标准株估算法对不同发育类型(包括发育型、成熟型和衰退型)唐古特白刺沙堆的形态特征(包括高度、半径、表面积、体积和土壤干质量)、唐古特白刺单株干质量(包括单株地上部和地下部的干质量及单株总干质量)和土壤碳储量进行了计算和比较,并对这些指标间的关系进行了分析.结果表明:成熟型沙堆的形态特征、唐古特白刺单株干质量和土壤碳储量均显著(P<0.05)高于发育型沙堆和衰退型沙堆;并且,除唐古特白刺单株地上部干质量外,发育型沙堆的上述指标均低于衰退型沙堆.据估算,样地内唐古特白刺植株的总碳储量为429.123 kg,土壤总碳储量为445.415 kg,且后者为前者的1.038倍.拟合曲线分析结果表明:唐古特白刺的单株干质量与沙堆各形态特征呈正相关,且与沙堆体积的相关性最高;土壤碳储量与沙堆各形态特征也呈正相关,且与沙堆体积和土壤干质量的相关性最高;成熟型沙堆中唐古特白刺单株干质量与土壤碳储量的相关性高于发育型沙堆和衰退型沙堆,且不同发育类型沙堆中唐古特白刺单株地下部干质量与土壤碳储量的相关性高于唐古特白刺单株地上部干质量和单株总干质量与土壤碳储量的相关性.研究结果显示:沙漠-河岸过渡带的唐古特白刺沙堆能够固定大量的碳,其中,成熟型沙堆的固碳能力最强;并且,唐古特白刺根系对土壤中碳的固定具有重要作用.
展开▼
