喀斯特峰丛洼地小流域不同群落凋落物分解动态及养分释放  

Decomposition dynamics and nutrient release of litter in different communities in small watersheds of karst peak-cluster depressions

作　　者：刘讯 赵久骞 张运林 LIU Xun;ZHAO Jiuqian;ZHANG Yunlin(School of Biological Sciences,Guizhou Education University,Guiyang 550018,Guizhou,China)

机构地区：[1]贵州师范学院生物科学学院,贵州贵阳550018

出　　处：《中南林业科技大学学报》2021年第11期98-107,共10页Journal of Central South University of Forestry & Technology

基　　金：贵州省社发攻关项目(黔科合SY4[2013]3164号);贵州省一流专业(生物科学)项目(教高厅函[2019]46号);贵州师范学院一流培育学科建设项目(2019YLPYXKB01)。

摘　　要：【目的】凋落物作为森林生态系统的重要组成部分,是林地土壤有机质的主要物质库和维持土壤肥力的基础。虽然国内外已经进行了很多关于凋落物分解的研究,但是针对喀斯特地区丛峰洼地小流域不同森林群落的混合凋落物分解还未有研究,而森林凋落物能够为喀斯特丛峰洼地的森林植被恢复提供养分和营养元素,其主要是通过分解释放养分参与物质循环实现的,因此森林凋落物分解速率及养分情况对于该地区生态恢复具有重要意义。【方法】以黔西北喀斯特峰丛洼地7个典型群落下凋落物为研究对象,于2019年收集7个群落下凋落物进行分解实验,并进行养分测定,包括有机碳、氮、磷含量测定,计算凋落物分解速率,建立分解速率模型。并分析不同分解时间下相同群落有机碳、氮、磷和化学计量的差异以及相同分解时间下不同群落间有机碳、氮、磷和化学计量的差异。【结果】1)7种群落的分解系数变化范围在0.043~0.073,分解t_(0.5)为0.8~1.2 a,分解t0.95为3.4~5.7 a。2)有机碳在7个群落中均表现为释放。有机氮除了F群落为释放外,其余6个群落都为富集。有机磷含量除了C群落为释放外,其余6个群落都为富集。3)碳氮比在7个群落中均为释放,碳磷比在7个群落中均为释放,氮磷比在A、C、D群落为富集,在B、E、F、G群落为释放。【结论】贵州省喀斯特地区丛峰洼地小流域不同森林群落的凋落物分解速率及养分变化情况与林分类型、立地条件等差异显著,建立得到分解率与化学指标之间的关系模型,对于该地区森林维持和植被恢复具有重要意义。【Objective】As an important part of forest ecosystem,litter is the main material reservoir of forest soil organic matter and the basis of maintaining soil fertility.Although a lot of research on litter decomposition has been carried out,there is no research on the mixed litter decomposition of different forest communities in karst area cluster peak depression small watershed.Forest litter can provide nutrients and nutrient elements for forest vegetation restoration in karst cluster peak depression,which is mainly realized through decomposition and release of nutrients to participate in the material cycle.Therefore,forest litter can provide nutrients and nutrient elements for forest vegetation restoration in karst cluster peak depression The decomposition rate and nutrient status of forest litter are important for ecological restoration in this area.【Method】The litter of seven typical communities in karst peak cluster depression of northwest Guizhou province was collected in 2019 for decomposition experiment,and the nutrient content,including organic carbon,nitrogen and phosphorus was determined.The decomposition rate of litter was calculated and the decomposition rate model was established.The differences of organic carbon,nitrogen,phosphorus and stoichiometry in the same community under different decomposition time and the differences of organic carbon,nitrogen,phosphorus and stoichiometry in different communities under the same decomposition time were analyzed.【Result】1)The decomposition coefficients of the seven communities ranged from 0.043 to 0.073,the decomposition t0.5 was 0.8 to 1.2 a,and the decomposition t0.95 was 3.4 to 5.7 a.2)Except F community,the other six communities were enriched in organic nitrogen.The content of organic phosphorus was enriched in all six communities except C community;3)the ratio of carbon to nitrogen was released in all seven communities,the ratio of carbon to phosphorus was released in all seven communities,the ratio of nitrogen to phosphorus was enriched in a,C an

关 键 词：峰丛洼地 凋落物 分解速率 凋落物质量 

分 类 号：S718.55[农业科学—林学]