关注全球气候变化情境下长江上游生态安全与农林清洁生产
Focus on ecological security and clean production of agriculture forestry in the upper reaches of Yangtz River under climate change scenarios
Abstract: Aim Litter humification is vital for carbon sequestration in terrestrial ecosystems. Probing the litter humification of treeline ecotone will be helpful to understand soil carbon afflux in alpine regions under climate change. Methods Foliar litter of six plant functional groups was chosen in an alpine treeline ecotone of the eastern Tibetan Plateau, and a field litterbag decompositi...
Abstract: Mixed litter decomposition is a common phenomenon in nature and is very important for the circulation of material through an ecosystem. Different plant functional groups (PFGs) are likely to interact during decomposition. It is unclear how mixed decomposition influences the release of multiple metallic elements, and the biogeochemical circulation mechanism in the alpine ecosystem rema...
摘要:[目的]为了解华西雨屏区亚热带不同植物功能型树种凋落叶功能性状特征,探讨不同植物功能型树种对环境的适应策略.[方法]以四川盆地西缘都江堰灵岩山亚热带森林群落为研究对象,采集了18种树种凋落叶,分为常绿阔叶、落叶阔叶和针叶3个植物功能型,比较分析碳(C)、氮(N)、磷(P)、木质素和纤维素及其化学计量比在不同功能型树种间的变异.[结果]常绿阔叶和落叶阔叶树种凋落叶N含量显著低于针叶树种,C:N比显著高于针叶树种;常绿阔...
【摘要】 【目的】了解四川盆地西缘人工林土壤有机碳组分的分布规律.【方法】采四川盆地西缘4种人工林(柳杉Cryptomeria fortunei、含笑Michelia wilsonii、桢楠Phoebe zhennan和麻栎Quercus acutissima)2个土壤层次(0~20 cm和20~40 cm)的土壤样品,测定土壤总有机碳、颗粒有机碳、轻组有机碳和易氧化有机碳的含量.【结果】麻栎人工林在0~20 cm土壤有机碳、颗粒有机碳和轻组有机碳含量分别为73.40、21.54和19.01 g/kg,显著高于...
摘要:以凋落物为载体的养分归还是生态系统物质循环的主要过程,也是林木生长所需养分的重要来源。相对于其他元素,钾(K)和钠(Na)在调节渗透压方面有着极其重要的作用,且淋溶作用强烈,极易流失,但缺乏必要关注。因此,以海拔3589 m高山峡谷区典型的四川红杉(Larix mastersiana)⁃岷江冷杉(Abies faxoniana)原始林为研究对象,在2015年9月到2016年8月期间调查了不同类型凋落物中K 和Na 元素在不同时期的归还特征。...
Abstract: As an arthropod biocide, naphthalene has been used in studies of the ecological functions of soil fauna for decades. However, its potential non-target effects on soil microorganisms may affect soil mineralization and litter decomposition processes. Therefore, we conducted an experiment with naphthalene adding to soil surface at a rate of 100 g·m-2 per month to examine the potential no...
摘要:镉(Cd)是一种有害重金属元素,能够伴随溪流水体流动和物质沉积影响下游流域的生态环境安全,但缺乏必要关注。 为 了解森林溪流Cd储量及其分配的动态变化特征,以岷江上游亚高山森林集水区的溪流为研究对象,在长度10-50、50-150、 150-260m区间内各选取5条典型溪流,研究Cd元素在亚高山森林⁃溪流⁃河流集合生态系统中的迁移过程。 结果表明:亚高山 森林溪流的Cd储量介于2.57-128.46mg/m2之间,主要储存于沉积物中;...
Abstract: Forest fire is a recurrent and serious problem which stirs major environmental, economic, and social concerns. Information on the temporal–spatial distribution of ignition probability and identifying the factors that drive the pattern of forest fire occurrences are the most challenging issues over the world. In this study, the spatial distribution and temporal variation in forest fi...
Abstract: Microbial communities and enzyme activity in soil are the functional link through which the vegetation type occupying a site, may alter soil processes fundamental to nutrient cycling. Roots are known to regulate soil carbon (C) input, but the impacts of different classes of roots on soil microbial community (as indexed by PLFAs) and enzyme activity are uncertain. Thus, the aim of th...
Abstract: Winter snow cover is a major driver of soil microbial processes in high-latitude and high-altitude ecosystems. Warming-induced reduction in snow cover as predicted under future climate scenarios may shift soil bacterial communities with consequences for soil carbon and nutrient cycling. The underlying mechanisms, however, remain elusive. In the present study, we conducted a snow manip...
Abstract: The degradations ofCellulose andligninfrom litterarecrucialprocesses forcarbon andnutrientcycling in forest ecosystems. However,theeffectsofsoilfaunaonthesedegradationprocesses areunclear despitetheirfunctional roles in litter fragmentation and microorganism regulation. Here we conducted a four-year field experiment using litterbags with two mesh sizes (3 and 0.04 mm) to assess the e...
ABSTRACT: Because climate change is predicted to have a strong impact on high-altitude ecosystems, a better knowledge of litter decomposition in alpine ecosystems is critical to improve our predictions of the effect of climate change on ecosystem processes and services such as nutrient cycling, carbon sequestration, and below-ground biodiversity. To evaluate the effects of vegetation types [alp...
Abstract: Base cation transfer from stemflow is an important process for nutrient transfer and plays a key role in maintaining the balance of soil nutrient pools. To research the differences of stemflow chemistry in mixed plantations, we conducted a continuous field experiment in the rainy zone of Western China from December 2016 to November 2017. Three representative mixed plantations, includi...
Abstract: Planted forests in China have continuously stored large amounts of vegetation carbon since the implementation of the National Key Forestry Ecology Projects (NKFEPs). However, the time variation of the contribution of NKFEP-covered planted forests to the national forest vegetation carbon storage has not been systematically documented. Moreover, predicting the future vegetation carbon s...
摘 要:植物对矿质元素的吸收和利用是衡量森林群落养分状况的重要指标. 为了解亚热带常绿阔叶林植物群落矿质元素分配特征,以华西雨屏区亚热带常绿阔叶林优势植物为研究对象,于2017年8月采集乔木、灌木和草本植物的根、茎、 皮、枝、叶样品,测定分析森林群落优势植物矿质元素K、Ca、Na、Mg的分配特征. 结果表明:优势植物矿质元素平均浓度表现为Ca > K > Mg > Na;不同功能群各元素浓度存在一定差异,K和Mg浓度以乔木植物最...
摘 要:为了解亚高山林区河岸带木质残体的持水能力,以王朗国家级自然保护区亚高山林区河岸带康定柳(Salix paraplesia)直径>30、30~20、20~10、10~5、5~2和2~1cm六个径级的木质残体为研究对象,运用浸泡模拟法研究了其吸水过程和持水能力随径级的变化特征。 结果表明:不同径级木质残体的最大持水量为1024.78~2674.67g·kg-1,不同径级木质残体的持水量大小顺...
Abstract: Reducing the threats of sulfate ion (SO42-) deposition to terrestrial ecosystems is a great challenge. The canopy interception effect on SO42-deposition has been well documented, but the interception efficiency of the gap edge remains unknown. Therefore, a subalpine dragon spruce (Picea asperata) plantation was evaluated in the upper reaches of the Yangtze River. The dynamics of the S...
Abstract:Litter decomposition is a major component of the nutrient cycle in forest ecosystems. It is generally accepted that higher initial quality and litter mixture contribute to increased mass loss, and the effects of soil fauna on litter decomposition is context-dependent. Meanwhile, the formation of gaps alters the hydrological and thermal conditions of the forest through the redistribut...
Abstract: Litter decomposition plays a critical role in regulating biogeochemical cycles in terrestrial ecosystems and is profoundly impacted by increasing atmospheric nitrogen (N) deposition. Here, a N manipulation experiment was conducted to explore the effects of N additions (0 kg N ha-1 yr-1, 20 kg N ha-1 yr-1 and 40 kg N ha-1 yr-1) on decay rates and nutrients release of two contrasting sp...
摘要:凋落叶分解所产生的水溶性组分(water soluble matter)是森林水陆不同生境碳和 养分迁移的重要载体。 本研究通过布设高寒森林4种代表物种凋落叶分解袋,即康定柳 (Salix paraplesia)、高山杜鹃(Rhododendron lapponicum)、方枝柏(Sabina saltuaria)和四川红 杉(Larix mastersiana),探讨其在林下地表、溪流和河岸带3种生境下不同分解时期(冻结初 期、冻结期、融化期、生长季节、生长季节后期)的水溶性组分及...
Abstract: Improved knowledge of biological diversity patterns associated with elevation and their driving factors is indispensable for developing ecological theories. However, the results for the elevational distribution patterns of soil fauna are not consistent due to differing climates and vegetation. Here, we present a comprehensive analysis of soil macroinvertebrate composition and structur...
ABSTRACT: Headwater streams are an essential link in the source and sink dynamics of heavy metals between terrestrial and aquatic ecosystems and are also critically important for downstream ecosystem processes and water quality. However, there is little available information about headwater streams. Therefore, the stream storage and distribution patterns of Cd, Pb, Ni, Cr, Cu, Mn and Zn were in...
AbstractPurpose Humification of plant detritus is an important pathway for soil organic matter formation. The long-standing studies considered that humification proceeds at very late stages of litter decomposition, while the degree of humification in newly shed litters before decomposition remains unclear. In this study, we aimed to explore the degree of humification and conjugate struc...