摘要
2013年11月,在鄱阳湖南矶湿地国家级自然保护区,沿水位梯度测定了岗地、天然堤、洲滩和水域7种植物群丛下的土壤有机碳、全氮和全磷含量,研究了土壤碳、氮、磷化学计量特征及其对水位梯度与植物群丛变化的响应,探讨了碳与养分比对土壤碳储量的指示作用。结果表明,0~30 cm深度土层的平均有机碳、全氮和全磷质量比分别为(16.27±4.18)mg/g、(1.28±0.24)mg/g和(0.77±0.14)mg/g;碳氮比、碳磷比和氮磷比的变化范围分别为4.35~30.86、3.61~52.19和0.52~4.31,其平均值分别为(12.60±5.40)、(19.73±13.28)和(1.58±0.90);随着水位梯度与群落类型的变化,土壤碳、氮、磷化学计量比发生显著变化,且土壤碳氮比和碳磷比的变化主要取决于有机碳含量,氮磷比的变化主要受控于全氮含量;岗地、天然堤、洲滩和水域0~30 cm深度土壤有机碳储量分别为4 103.57 g/m2、8 248.01 g/m2、5 143.58 g/m2和2 225.57 g/m2;随着碳氮比的增大,有机碳储量总体上呈增加趋势。
Carbon-nitrogen, carbon-phosphorus and nitrogen-phosphorus ratios are critical indicators of biogeochemical coupling in terrestrial ecosystems. Stoichiometric homoeostasis plays important role in modulating structure, functioning and stability of ecosystems. The dynamics of soil nutrients and moisture of the wetlands are more frequent than terrestrial ecosystem. Poyanghu Lake is the largest freshwater lake in China, with huge areas of wetlands occurring during drawdown periods in a year. In this study, a typical wetland was selected in the Nanji Wetland National Nature Reserve. Subsequently, soil organic carbon, total nitrogen and total phosphorus contents under 7 types of plant communities were measured along water level gradient. The objectives were to clarify the soil carbon-nitrogen, carbon-phosphorus and nitrogen-phosphorus ratios in response to water level gradient and community change, and discuss the relation between soil carbon to nutrient element ratio and carbon storage. The results showed that mean organic carbon, total nitrogen and phosphorus contents were(16.27 ± 4.18) mg/g,(1.28 ± 0.24) mg/g and(0.77 ± 0.14) mg/g in soil of 0-30 cm depth, respectively.The ratios of carbon-nitrogen, carbon-phosphorus and nitrogen-phosphorus varied from 4.35 to 30.86, 3.61 to52.19 and 0.52 to 4.31, respectively. The mean carbon-nitrogen, carbon-phosphorus and nitrogen-phosphorus ratios were(12.60 ± 5.40),(19.73 ± 13.28) and(1.58 ± 0.90), respectively. Soil carbon-nitrogen, carbon-phosphorus and nitrogen-phosphorus ratios were mainly affected by soil water regime and community type in the wetlands. Moreover, the variations of carbon-nitrogen and carbon-phosphorus ratios were mainly controlled by soil organic carbon content. The variation of nitrogen-phosphorus ratio was highly dependent on soil total nitrogen content. Soil carbon-nitrogen ratio was relatively low, which was in favor of wetland carbon accumulation. The mean organic carbon storage in soil of 0-30 cm depth was 4 103.57 g/m2, 8 248.01 g/m2, 5 143.58
出处
《湿地科学》
CSCD
北大核心
2015年第3期374-380,共7页
Wetland Science
基金
国家自然科学基金项目(31460129和31270522)
鄱阳湖湿地与流域研究教育部重点实验室开放基金项目(PK2013001)资助
关键词
化学计量比
水位梯度
植物类型
鄱阳湖
南矶湿地
stoichiometry
water level gradient
plant type
Poyang Lake
Nanji wetlands
