项目来源

国家重点研发计划(NKRD)

项目主持人

王国梁

项目受资助机构

中国科学院生态环境研究中心

立项年度

2022

立项时间

未公开

项目编号

2022YFF1300403

研究期限

未知 / 未知

项目级别

国家级

受资助金额

268.00万元

学科

典型脆弱生态系统保护与修复

学科代码

未公开

基金类别

未公开

关键词

黄土缓坡丘陵区 ; 低效林 ; 水土保持 ; 碳汇 ; The hilly areas with gentle slopes of loess ; inefficient forest ; soil and water conservation ; carbon sink

参与者

彭信浩；张钦弟；李宗善；童兵；陈胜楠；卫伟；朱琪

参与机构

山西师范大学

项目标书摘要：针对黄土高原人工林结构不合理、生长不良及可持续性差等问题，重点聚焦定西龙潭流域立地条件下整地方式和林分结构调整对人工林水碳耦合效应，小流域尺度林分结构空间优化格局识别及生态效应，以及区域及国家尺度上的人工林生长衰退特征及林分调整的水碳效应。结果表明:1)立地条件下，间伐明显提高人工油松林的净降雨量、降雨利用效率和生物量，且间伐显著提高林地浅层土壤含水量和土壤表层细根生物量，而对深层土壤水影响较小。与反坡台油松林相比，间伐能显著改善鱼鳞坑油松林的土壤水分条件。2)小流域尺度上，油松鱼鳞坑的土壤多功能性高于油松反坡台。油松—反坡台小区的减流减沙效益最高，鱼鳞坑和反坡台的土壤含水量均显著大于对照样地，鱼鳞坑土壤含水量显著大于反坡台。3)区域上，由于撂荒及损坏的梯田区域的还林及农林混合种植模式的推广实施，黄土高原坡改梯整地工程下用地转移类型主要是耕地与草地林地化；人工林生长和导水功能的解耦现象导致生长发生衰退且具有空间南北分异特征；全国尺度上人工林间伐显著增加了表土层和底土层有机碳含量，轻度和中度间伐均显著增加了表土层和底土层有机碳含量，重度间伐下有机碳的降低可能与枯落物和根系密度的降低有关，另外干旱半干旱区域(低经度、高纬度、低降雨、低年均温)人工林间伐会产生比湿润区域更高的土壤碳收益效果。

Application Abstract: In response to issues such as the unreasonable structure,poor growth,and low sustainability of forests in the Loess Plateau,this study focused on the effects of land preparation methods and stand structure adjustment on the water-carbon coupling in the Longtan watershed of Dingxi.We also investigated the spatial optimization pattern recognition of stand structure and its ecological effects at watershed scale,the growth decline characteristics of planted forests,and the water-carbon effects of stand adjustment at regional and national scales.The results indicated that:At stand conditions,thinning significantly increased the net rainfall,rainfall use efficiency,and biomass of Chinese pine forests.Thinning also significantly increased soil moisture and biomass of fine roots in the shallow layer,with a minimal impact on deep soil moisture.Thinning significantly improved the soil moisture conditions of Chinese pine fish-scale pit compared to Chinese pine on the opposing slope.At watershed scale,the soil multifunctionality of Chinese pine fish-scale pits was higher than Chinese pine on opposing slopes.The highest reduction of runoff and sediment yield was observed in Chinese pine-opposing slope areas.The soil water of fish-scale pits and opposing slopes was significantly greater than control plots,with the soil water of fish-scale pits being significantly greater than opposing slopes.At regional scale,due to the fallowing and restoration of damaged terraced areas,as well as the promotion and implementation of afforestation and agroforestry mixed planting patterns,the conversion of land use under the slope-to-ladder project in the Loess Plateau was mainly characterized by the transformation of arable land and grassland into forestland.The decoupling of growth and water conduction functions in planted forests led to the occurrence of growth decline,and the decline showed spatial north-south differentiation characteristics.At national scale,thinning significantly increased the organic carbon content in the top and subsoil layers.Slight and moderate thinning both significantly increased the organic carbon content in the top and subsoil layers.The decrease in organic carbon under severe thinning may be related to the reduction in litter and root density.Additionally,in arid and semi-arid regions(low longitude,high latitude,low rainfall,low average temperature),thinning may result in higher soil carbon benefits than humid regions.

项目受资助省

北京市

联系人信息

卫伟：weiwei@rcees.ac.cn