%0 Journal Article %T 鄱阳湖湿地枯丰水期转换对灰化薹草(Carex cinerascens Kükenth)枯落物分解及碳、氮、磷释放的影响 %T The impact of dry and flood seasons shifts on Carex cinerascens Kükenth litter decomposition and the release of C, N, P in Lake Poyang wetland* %A 张全军,张广帅,于秀波,刘宇,夏少霞 %A Zhang Quanjun %A Zhang Guangshuai %A Yu Xiubo %A Liu Yu %A Xia Shaoxia %J 湖泊科学 %J Journal of Lake Sciences %@ 1003-5427 %V 33 %N 5 %D 2021 %P 1508-1519 %K 水文过程;分解速率;养分归还;化学计量比;鄱阳湖湿地 %K Hydrological process;decomposition rate;nutrient relative return index;stoichiometry;Lake Poyang wetland %X 枯落物分解过程是湿地生态系统生源要素生物地球化学循环的关键环节.研究湿地枯落物分解过程是揭示湿地生态功能机理的关键.洪泛平原湿地枯水期的地下水位及丰水期的洪水淹没深度和持续时间都是湿地枯落物分解过程的重要调控因素.本研究采用分解袋法和原位观测模拟试验研究了鄱阳湖优势湿地植物薹草枯落物分解及碳、氮、磷释放对枯水期转化到丰水期的响应.利用鄱阳湖湿地洲滩的高程差选取4个水位梯度,在枯水期4个梯度分别是G-H(高地下水位带)、G-MH(中高地下水位带)、G-ML(中低地下水位带)和G-L(低地下水位带),而在丰水期这4个梯度又转变为G-H(深淹水带)、G-MH(中度深淹水带)、G-ML(中度浅淹水带)和G-L(浅淹水带).研究结果表明:无论在枯水期内还是在丰水期内,4个梯度带之间薹草枯落物干物质残留率及分解速率都具有极显著的差异性.在枯水期内,4个梯度分解速率的大小关系为:G-H > G-MH > G-ML > G-L,在丰水期内,分解速率大小关系发生了反转,即为:G-L > G-ML > G-MH > G-H.薹草枯落物碳、氮、磷相对归还指数表现出与干物质相似的差异性.本研究可为湿地生态系统生物地球化学循环过程对水文节律的响应研究提供数据和理论支撑,也为鄱阳湖基于水位调控下的生态系统管理提供新的认识和决策依据. %X The litter decomposition process is an impotent link in the biogeochemical cycle of the biological elements of the wetland ecosystem. Studying the decomposition process of wetland litter is the key to reveal the wetland ecological function mechanism. Groundwater level of floodplain wetland during the dry season and the depth and duration of flooding during the flood season are both important regulators of wetland litter decomposition. In this study, the decomposition bag method and in situ observation simulation experiments were used to study the response of the litter decomposition and carbon, nitrogen and phosphorus release of the dominant plant Carex cinerascens Kükenth litter to the shift of dry and flood seasons in Lake Poyang wetland. Four gradient belts were selected using the elevation difference of the wetland beach of Lake Poyang. The four gradients are G-H (high groundwater level belt), G-MH (medium-high groundwater level belt), G-ML (medium-low groundwater level belt) and G-L (low groundwater level belt) during the dry season. The four gradients are transformed into G-H (deep flooded zone), G-MH (moderately deep flooded zone), G-ML (moderately shallow flooded zone) and G-L (shallow flooded zone) during the flood season. The results showed that the dry mass remaining rate and decomposition rate of the C. cinerascens litter among the four gradient belts are the extremely significant difference. During the dry season, the relationship of the four gradient decomposition rates is: G-H>G-MH>G-ML> G-L. However, the relationship is perfectly reversed: G-L>G-ML> G-MH> G-H during the flood season. The relative return indexes of carbon, nitrogen, and phosphorus of the C. cinerascens litter showed similar differences with dry mass. This study could provide data and theoretical support for the study of the response of the biogeochemical cycling of wetland ecosystem to hydrological rhythm and provide new knowledge and decision-making basis for the ecosystem management of Lake Poyang based on water level regulation. %R 10.18307/2021.0519 %U http://www.jlakes.org/ch/reader/view_abstract.aspx %1 JIS Version 3.0.0