若尔盖高原退化湿地土壤有机碳储量

为了定量评价若尔盖高原泥炭沼泽湿地退化的碳储存潜力,研究通过土壤剖面法,收集了3个样点的泥炭沼泽湿地土壤样品(原始泥炭地0—200cm、中度退化沼泽湿地0—100cm和重度退化泥炭地0—100cm)。研究表明:(1)中度退化沼泽湿地(1.11±0.18g/cm~3)和重度退化泥炭地(0.72±0.04g/cm~3)土壤容重平均值较原始泥炭地增加了251.8%和129.7%;中度退化沼泽湿地(46.18±6.61g/kg)和重度退化泥炭地(87.37±6.36g/kg)土壤有机碳含量平均值较原始泥炭地降低了74.2%和51.1%。(2)土层深度为0—100cm时,原始泥炭地土壤有机碳储量较中度退化沼泽湿地(384.73±95.57t/hm~2)显著高了47.0%,而与重度退化泥炭地(518.39±33.07t/hm~2)土壤有机碳储量无显著差异;当原始泥炭地有机层增加到0—200cm后,中度退化沼泽湿地和重度退化泥炭地土壤有机碳储量较原始泥炭地(1 088.17±172.84t/hm~2)降低了64.6%和52.4%,退化湿地土壤有机碳储量的降低可能主要是土壤有机碳含量降低的原因。尽管退化湿地土壤有机碳储量下降,但仍是中国(102.89t/hm~2)和全球(116.56t/hm~2)陆地土壤有机碳储量的3~5倍,该研究可为保护与恢复若尔盖高原湿地提供科学依据。

Soil Organic Carbon Storage in the Degraded Wetlands in Zoigê Plateau

To quantify the soil organic carbon storage of the degraded marshy wetland in the Zoigê Plateau,China.Three sites (original peatland at depth of 0-200 cm,moderately degraded marshy wetland at depth of 0-100 cm,and severely degraded peatland at depth of 0-100 cm) were chosen and the soil samples were collected using the soil profile methods.This result showed that the soil bulk density (1.11±0.18 g/cm3) in the moderately degraded marshy wetland was 251.8％ higher than that of the original peatland,and soil bulk density in the severely degraded peatland (0.72±0.04 g/cm3) was 129.7％ higher than that of the original peatland,respectively.Compared to the original peatland,the soil organic carbon contents in the moderately degraded marshy wetland (46.18±6.61 g/kg) and severely degraded peatland (87.37±6.36 g/kg) have reduced by 74.2％ and 51.1％,respectively.As the soil samples were collected at depth of 0-100 cm,the soil organic carbon storage in the original peatland was 47.0％ significantly higher than that of the moderately degraded marshy wetland (384.73±95.57 t/hm2),but difference between the soil organic carbon storage in original peatland and that in severely degraded peatland (518.39±33.07 t/hm2) were no significant.However,the soil samples were a depth of 0-200 cm for the original peatland,the soil organic carbon storage in the moderately degraded marshy wetland was 64.6％ significantly lower than that of the original peatland (1 088.17±172.84 t/hm2),the soil organic carbon storage in the severely degraded peatland was 52.4％ significantly lower than that of the original peatland,respectively.This result could be main attribute to the decreases of the soil organic carbon contents in the degraded wetlands.Although the soil organic carbon storages in degraded wetland decrease,these values are still 3～5 times of that in Chinese or Global land soil (at depth of 0-100 cm).This result can provide useful information for the protection and restoration wetland in the Zoigê Plateau.