贡嘎山海螺沟冰川退缩区4种常见树种的异速生长方程

【目的】异速生长方程是构建林木生物量最简单常用的方法,本研究旨在为川西亚高山森林生物量及碳储量估测提供有效的研究方法,同时为异速生长模型优化以及植被原生演替过程研究提供基础依据。【方法】本文基于海螺沟冰川退缩区植被原生演替过程中主要树种的生物量实测数据,通过模型将树木的总生物量及不同组分(如枝、叶、树干、根等)生物量与胸径和树高等易测指标联系起来,建立了各树种总生物量及各组分生物量异速生长方程。【结果】引入树高(H)的二元模型拟合效果要优于一元模型,同一模型对地上和树干生物量估计精度要优于枝叶和地下生物量的估计。【结论】以D^2H为自变量的方程对树干和地上生物量的拟合效果更好,而以D^3/H为自变量的方程更适合枝叶和根的生物量拟合。在实际工作中,考虑到野外测量的难度,可以采用一元模型W=aD^b。本次构建的生物量异速生长方程对于青藏高原东缘亚高山森林生态系统生物量的估算以及植被演替过程中生物量的动态研究具有重要参考价值。

二氧化氯氧化法处理含氰废水试验研究

针对某含氰含铜废液,采用二氧化氯氧化法脱除废液中氰,再用硫化法沉淀回收溶液中铜。结果表明,二氧化氯氧化法除氰合理工艺条件为:反应温度25℃、溶液初始pH=9.5、反应时间60 min、二氧化氯气体流速60 mL/min,此时除氰率达到96%以上;硫化沉淀法回收除氰后液中的铜,合理工艺条件为:反应温度25℃、反应时间60 min、溶液初始pH=3、搅拌速度300 r/min、硫化钠用量为理论量3倍,此时沉铜率达到93%以上。

Phosphorus Biogeochemical Cycle Research in Mountainous Ecosystems

Phosphorus(P),as a limiting nutrient,plays a crucial role in the mountainous ecosystem development.Its biogeochemical cycle in mountainous ecosystems determines the bioavailability and sustainable supply of P,and thus becomes a crucial process which needs to be fully understood and described for ecological and environmental conservation.However,most of research about P biogeochemical processes has been carried out in aquatic environment and agronomic field,but rare researches have been done in mountain ecosystem.In the present review,we summarize researches on P biogeochemical cycle concerning mountain ecosystem in recent decades,including rock weathering,the release,transformation and bioavailability of P,interactions between the P biological cycle and microbial and plant life,as well as the development of models.Based on the state of art,we propose the future work on this direction,including the integration of all these research,the development of a practical model to understand the P biogeochemical cycle and its bioavailability,and to provide a reference for ecological and environmental conservation of mountainous ecosystems and lowland aquatic systems.

Effect of an Anionic Surfactant on Hydraulic Conductivities of Sodium- and Calcium-Saturated Soils

The effect of sodium dodecylbenzenesulfonate (SDBS), an anionic surfactant used widely in household products and industrial processes, on saturated hydraulic conductivities (Ksat) of an Anthrosol saturated with sodium (Na-soil) or calcium (Ca-soil) was analyzed in a laboratory experiment using the constant head method, and adsorption and dispersion experiments were also conducted to infer the possible mechanisms of Ksat fluctuations. The results showed that SDBS was more intensely adsorbed in the Ca-soil than in the Na-soil. With an increase in the SDBS concentration, the stability of the Na-soil suspensions decreased when the SDBS concentration was less than 1.2 mmol L-1 and then above this concentration, increased markedly, while the stability of the Ca-soil suspensions increased gradually at all SDBS concentrations studied. With an increase in the SDBS concentration, the Ksat of the Na-soil increased, which resulted mainly from the increase of water channels in the soil because of the coagulation of the soil particles, while the Ksat of Ca-soil decreased mainly on account of the clogging of partial water channels by precipitated Ca(DBS)2 and the fine soil particles generated.

贡嘎山峨眉冷杉成熟林碳利用效率季节动态及其影响因子

碳利用效率(CUE)是植被生态系统的一个重要功能参数,反映了植被生态系统的固碳能力,适用于分析不同时间段内器官、个体和群落等不同层次的碳收支趋势,因而有助于对陆地生态系统碳功能的确定与预测,引起了广泛关注。该研究采用生物计量法,测定和计算了川西贡嘎山东坡峨眉冷杉(Abiesfabri)成熟林树木不同器官的呼吸与净生产力动态,分析了乔木层及其各器官CUE动态及主要影响因子,并估算了乔木层不同径级树木CUE。主要结果:(1)乔木层各器官月呼吸速率与温度呈正相关关系,以细根月呼吸速率为最大;不同径级树木年呼吸量无显著差异,以小径级树木树干的年呼吸量为最小。(2)乔木层细根和树干月净初级生产力(NPP)均随温度增加而增加,以细根月NPP为最大。小径级树木年NPP最大,其针叶年NPP也显著高于中径级和大径级树木。(3)林分乔木层及其各器官CUE大多集中在0.30–0.60之间,其中细根、树干CUE具有相似的月变化动态,均随温度的升高而上升。不同径级树木CUE及树干和针叶CUE均随树木个体的增大而明显下降。(4)气温和土壤温度与乔木层树干和细根CUE呈正相关关系,而降水量与针叶CUE呈负相关关系。细根CUE与树干CUE呈正相关关系,与针叶CUE呈负相关关系。峨眉冷杉成熟林乔木层CUE主要取决于树干和细根CUE。该研究证实了川西亚高山暗针叶成熟林仍具有较强的碳汇功能,在区域碳储存和森林生态系统碳循环中发挥着极其重要的作用。