土壤是陆地生态系统有机碳赋存的重要载体.土壤碳库规模和周转的变化都可能影响大气中的CO_(2)浓度,促使全球气候变暖.茶树是我国重要的经济作物,作为多年生常绿作物,在有机碳的固存、分配与稳定中发挥着重要作用.针对茶园土壤有机碳研...土壤是陆地生态系统有机碳赋存的重要载体.土壤碳库规模和周转的变化都可能影响大气中的CO_(2)浓度,促使全球气候变暖.茶树是我国重要的经济作物,作为多年生常绿作物,在有机碳的固存、分配与稳定中发挥着重要作用.针对茶园土壤有机碳研究仍存在诸多不确定性,尚缺乏系统认识与现状计量.为明晰茶园土壤有机碳库组分和稳定性,基于文献检索整理数据归纳结果,以Web of Science(WOS)和CNKI为数据源,系统剖析和总结1990-2023年共1906篇国内外茶园有机碳领域的研究成果及研究热点,并对茶园土壤有机碳库组分、影响因素及其稳定性进行系统梳理.结果表明:①该领域近30年文献量逐年增加且处于快速增长阶段,国际上的研究热点主要聚集在“碳”“茶树种植”“生长”“管理”等,国内的研究热点主要聚集在“茶园土壤”“土壤养分”“土壤肥力”等.②综合国内外的研究,茶园土壤有机碳含量与pH(R^(2)=0.0771)呈显著负相关,与黏粒含量(R^(2)=0.0771)、降水量(R^(2)=0.1999)、海拔(R^(2)=0.2489)、碱解氮含量(R^(2)=0.6842)和有效磷含量(R^(2)=0.6375)均呈显著正相关.③茶园土壤有机碳库的稳定性主要通过团聚体物理保护、化学键合和结构组分稳定以及生物调控来实现.未来还需结合多种现代技术,加强构建茶园土壤有机碳库影响因素、稳定机制以及预测模型和空间联网的长期定位观测研究,并因地制宜地构建茶园土壤碳增汇技术模式.研究结果对深入认知碳循环关键过程与机理,实现茶园可持续固碳具有重要意义.展开更多
Ciliates of the heterotrich family Folliculinidae are characterized by their transparent lorica,conspicuous peristomial lobes pair and dimorphic life cycle,a sessile trophont and a motile swarmer.However,understanding...Ciliates of the heterotrich family Folliculinidae are characterized by their transparent lorica,conspicuous peristomial lobes pair and dimorphic life cycle,a sessile trophont and a motile swarmer.However,understanding their biodiversity and systematics is relatively poor.In the present study,two species representing two genera of folliculinids,which were collected from marine and brackish habitats in China,were investigated with morphological and molecular methods.The genus Diafolliculina n.gen.is established for D.longilobata n.sp.Detailed morphological redescriptions for another species Eufolliculina is provided.Moreover,phylogenetic analysis based on small subunit ribosomal DNA(SSU rDNA)sequences showed that 1)all two genera locate in the Folliculinidae clade;2)Metafolliculina clusters with Eufolliculina;and 3)two genera(Diafolliculina and Ampullofolliculina)with a lorica closure device have close affinities with Folliculina.The lorica of Diafolliculina and Ampullofolliculina lacks a closure device,thereby the phylogeney contradicts the morphology-based classification.展开更多
文摘土壤是陆地生态系统有机碳赋存的重要载体.土壤碳库规模和周转的变化都可能影响大气中的CO_(2)浓度,促使全球气候变暖.茶树是我国重要的经济作物,作为多年生常绿作物,在有机碳的固存、分配与稳定中发挥着重要作用.针对茶园土壤有机碳研究仍存在诸多不确定性,尚缺乏系统认识与现状计量.为明晰茶园土壤有机碳库组分和稳定性,基于文献检索整理数据归纳结果,以Web of Science(WOS)和CNKI为数据源,系统剖析和总结1990-2023年共1906篇国内外茶园有机碳领域的研究成果及研究热点,并对茶园土壤有机碳库组分、影响因素及其稳定性进行系统梳理.结果表明:①该领域近30年文献量逐年增加且处于快速增长阶段,国际上的研究热点主要聚集在“碳”“茶树种植”“生长”“管理”等,国内的研究热点主要聚集在“茶园土壤”“土壤养分”“土壤肥力”等.②综合国内外的研究,茶园土壤有机碳含量与pH(R^(2)=0.0771)呈显著负相关,与黏粒含量(R^(2)=0.0771)、降水量(R^(2)=0.1999)、海拔(R^(2)=0.2489)、碱解氮含量(R^(2)=0.6842)和有效磷含量(R^(2)=0.6375)均呈显著正相关.③茶园土壤有机碳库的稳定性主要通过团聚体物理保护、化学键合和结构组分稳定以及生物调控来实现.未来还需结合多种现代技术,加强构建茶园土壤有机碳库影响因素、稳定机制以及预测模型和空间联网的长期定位观测研究,并因地制宜地构建茶园土壤碳增汇技术模式.研究结果对深入认知碳循环关键过程与机理,实现茶园可持续固碳具有重要意义.
基金This work was supported by the National Natural Science Foundation of China(No.31970398)the National Key Research and Development Program of China(No.2018YFD0900701)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2019333).
文摘Ciliates of the heterotrich family Folliculinidae are characterized by their transparent lorica,conspicuous peristomial lobes pair and dimorphic life cycle,a sessile trophont and a motile swarmer.However,understanding their biodiversity and systematics is relatively poor.In the present study,two species representing two genera of folliculinids,which were collected from marine and brackish habitats in China,were investigated with morphological and molecular methods.The genus Diafolliculina n.gen.is established for D.longilobata n.sp.Detailed morphological redescriptions for another species Eufolliculina is provided.Moreover,phylogenetic analysis based on small subunit ribosomal DNA(SSU rDNA)sequences showed that 1)all two genera locate in the Folliculinidae clade;2)Metafolliculina clusters with Eufolliculina;and 3)two genera(Diafolliculina and Ampullofolliculina)with a lorica closure device have close affinities with Folliculina.The lorica of Diafolliculina and Ampullofolliculina lacks a closure device,thereby the phylogeney contradicts the morphology-based classification.
