摘要
为明确湿地退化过程中枯落物分解动态和营养元素变化趋势,本研究采用空间替代时间的方法选取未退化原始沼泽(UP)、轻度退化沼泽(LDP)、重度退化沼泽(HDP)和排水造林地(DA)内的枯落物为研究对象,探讨泥炭沼泽退化过程中枯落物的分解速率及碳、氮、磷释放动态特征.结果表明,不同退化阶段枯落物失重率、分解速率及营养元素相对归还指数均具有显著的差异.0～90 d内各样地枯落物的分解速率和失重率较高,分解 120 d后,UP、LDP、HDP和DA样地枯落物的失重率分别为初始质量的 15.31%、11.69%、7.16%和 20.11%,总体表现为DA样地的分解速率最快.碳相对归还指数(CRRI)依次为 17.32%、16.72%、4.22%和 20.17%,氮相对归还指数(NRRI)依次为-0.86%、-25.22%、28.03%和 5.15%,磷相对归还指数(PRRI)依次为-4.57%、-97.03%、6.19%和-29.56%.总体上各样地碳元素表现为净释放模式;HDP和DA样地枯落物氮元素总体上表现为净释放模式,LDP表现为净积累模式;LDP、HDP和DA样地枯落物磷元素总体上表现为净积累模式,UP表现为净释放模式.
Abstract
This study aims to investigate the decomposition rate and dynamic characteristics of carbon,nitrogen,and phosphorus release of litter during the degradation process of peatland,in an attempt to provide certain basic data for restoration of degraded peatland.The litter were collected from four types of peatlands,including undegraded peatland(UP),lightly degraded peatland(LDP),heavily degraded peatland(HDP),drainage afforestation(DA).The results showed that there were significant differences of mass loss rate,decomposition rates,and carbon relative return index(CRRI),nitrogen relative return index(NRRI),phosphorus relativereturm index(PRRI)between four types of peatlands.During the experiment period of 90 days,the litter had higher mass loss rate and decomposition rates than the other times.After the 120 days,the litter from UP lost 15.31 percent of its weight,LDP lost 11.69 percent of its weight,HDP lost 7.16 percent of its weight,DA lost 20.11 percent of its weight,and DA had highest decomposition rates.The CRRIs of four types of peatlands were 17.32%,16.72%,4.22%and 20.17%,the NRRIs of them were-0.86%,-25.22%,28.03%and 5.15%,andthe PRRIsof them were 4.57%,-97.03%,6.19%and-29.56%,respectively.The C of four types of peatlands showed a net release pattern,the N of the litter from HDP and DA showed a net release pattern,but the litter from LDP showed a net accumulation pattern,the P of the litter from LDP,HDP and DA showed a net accumulation pattern,but DA showed a net release pattern.
基金项目
吉林省自然科学基金项目(YDZJ202301ZYTS235)
吉林省公益性科研院所基本科研业务费项目(GY-2022-13)
吉林省公益性科研院所基本科研业务费项目(GY-2023-10)
吉林省林业自主研发项目(2022-001)
NETL
NSTL
万方数据