Heterotrophic Nano- and Microplankton under Conditions of Anthropogenic Eutrophication of the Bay of Novorossiisk

Seasonal and long-term dynamics of heterotrophic plankton in the Bay of Novorossiisk are discussed. It is shown that specific variation in the biomass of nanoheterotrophs and infusoria is associated with the processes of anthropogenic water eutrophication. The biomass of infusoria has increased ten times and that of zooflagellates two times since 1985–1986. Infusoria of the genera Strombidium, Strobilidium, and Mesodiniumare dominant in the protozoan plankton. The annual average level of Oligotrichadevelopment in the bay is characteristic of eutrophic water bodies (112–417 mg/m³); in the spring–summer season, however, it may increase to 500–1034 mg/m³. In the part of the bay near the port, which is exposed to a strong anthropogenic impact, the biomass of ciliate protozoa can reach 2 g/m³.     

花江峡谷石漠化土地生态重建及其启示

尽管西南岩溶地区石漠化趋势严重,但真正做到生态、经济、社会三效益统一的岩溶石漠化生态重建模式的实践工作却做得很少。且对于这些实践活动还缺乏理论的总结和思考。花江峡谷顶坛片区,充分利用当地的适生植物资源和干热资源优势在石漠化土地上种植花椒、砂仁等喜热耐旱的经济作物,在恢复和治理生态的前提下成功调整了农业内部结构,形成以花椒规模种植为核心心的特色产业,利用雨水、坡面水、岩溶裂隙水,实行参与式社区管理,使环境、经济与社区文化得以可持续发展。“顶坛”模式是充分利用岩溶环境资源优势,高山地保护于特色农业开发之中的一个成功例子。它启示我们,岩溶石漠化土地恢复重建必须重新认识岩溶环境优势。因地制宜,对过去侧重于水土保持的传统治理模式进行创新。     

亚高山旅游景区岩溶地下水水化学动态变化及其影响因素

岩溶地下水是岩溶区重要的水资源,因岩溶水文系统具有敏感性和脆弱性,其一旦遭受污染便很难再恢复。以重庆亚高山金佛山水房泉为例,通过计算2008年和2016年各水化学参数的浓度增降幅度和地球化学敏感性指数,对比分析各水化学参数及其地球化学敏感性变化特征。结果表明：水房泉水化学类型为Ca-HCO₃型,受水 岩作用控制。旅游活动产生的生活污水自2013年起被分成两条管道,住宿排污经过泉域内化粪池的沉淀降解后排入地下,使得2016年水房泉中K⁺、Na⁺、PO₄^3-浓度较2008年降低,显示化粪池对污染物具有有效的调节作用;而餐饮排污未经处理仍直接排入地下,导致流域出口水房泉中Cl^-、NO₃^-浓度呈翻倍增长,水质恶化。污水还加剧了碳酸盐岩的溶蚀,地下水中HCO₃^-、Ca²⁺、Mg²⁺浓度上升。由于旅游高峰期与非高峰期的游客量差距逐渐缩小,2016年各化学组分的敏感性指数多低于2008年,地下水受旅游活动影响的时间变长;分别对比不同水文年各主量组分的敏感性指数大小和离子当量浓度大小,发现2008年两者排序基本一致,而2016年较为混乱,这可能表明研究区地下水系统逐渐从有序转向无序的状态,稳定性被破坏,熵值增大。     

Dynamics of growth and seed production in the Siberian stone pine: The level and pattern of variation in characters

A statistical analysis of interannual variation in a set of vegetative and generative characters over 13 years has been performed to characterize the growth and seed production dynamics of the Siberian stone pine (Pinus sibirica Du Tour) in the southeast of the forest zone in western Siberia. The results have shown that the range of fluctuations in most of vegetative characters is ordinary and their distribution is close to normal. The range of fluctuations in many generative characters is enormous (from 0 to +∞), and the distribution of their values is usually skewed, with low values being recorded several times more frequently than high values. Most variable are the proportion of abortive cones and other characters that are determined mainly in the spring of the pollination year. These characters account for a very high level of variation in the total seed production.     

Appropriateness of needles of different conifer species for the feeding and growth of larvae from two populations of the Siberian moth

A comparison of two Siberian moth populations from the Altai Republic (feeding on Siberian fir) and the Tyva Republic (feeding on Siberian larch) has revealed no differences between them with respect to ecophysiological parameters of larval growth and feeding on needles of the same conifer species under laboratory conditions. The index of appropriateness of food plants for the larvae from both populations decreases in the series larch > fir > spruce > pine. The age-related dynamics of parameters characterizing the feeding and growth of larvae are independent of the population to which the insects belong.     

贵州喀斯特土石山区水土保持生态经济型植被恢复模式

以贵州省喀斯特土石山区为例,通过总结前人的研究成果和中国科学院亚热带农业生态研究所喀斯特生态实验站的部分试验数据,从全局性、紧迫性、高效性、层次性、可持续性、创新性与多样性的角度提出了在贵州喀斯特土石山区的急坡地、陡坡地、缓陡坡地其水土保持生态经济型植被恢复模式分别采用3种典型模式,即:灌草模式,乔灌草模式与林果模式,以期促进该区域的生态、经济与社会的全面协调与可持续发展。     

Unsteadiness of COD in the Upper and Middle Reaches of Minjiang River

This paper explores and identifies the rules of the unsteady evolution of COD in the upper and middle reaches of Minjiang River through multi-scale analysis on the weekly COD data for the last six years provided by the Water Quality Monitoring Station,Minjiang River Bridge,Leshan City,Sichuan Province.The results of the wavelet analysis indicate that the COD index oscillates alternatively and differently at each time-scale in an oneyear cycle,and the density of COD,subjected to the runoff volume,the effects of Wenchuan Earthquake and agricultural seeding and industrial construction,etc.,is high in winter and spring,mild in summer and autumn.     

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

Abstract

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.     

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

1INTRODUCTIONResources and environment crisis are accompanied byincreasing economic development pressures and rapidpopulation growth in many countries of the world(RobSwart,1996).Ecological security is a hotspot.Majorityof scholars have taken in the hot discussions of ecologicalsecurity of different regions,most of which is differentfrom their background of subjects(Alex F.Mc Calla,1999;Xiao Duning,Chen Wenbo and Guo Fuliang,2002).With the development of GIS,GPS,RS and modeltechno…     

秸秆还田对稻田温室气体排放的影响:Meta分析——以长江中下游地区为例

全球气候变暖是人类面临的严峻挑战,稻田生态系统在全球气候变暖中起到重要的作用。目前已有许多学者通过大田试验的方法研究了不同秸秆还田方式下温室气体排放的特征,但由于试验地点等因素的不同导致最终的结果差异很大。通过整合这些结果来研究区域内不同秸秆还田方式(翻耕秸秆还田(CTS)、免耕秸秆还田(NTS)和旋耕秸秆还田(RTS))下稻田温室气体排放的特征,能够准确地反映一定区域内稻田生态系统的净减排潜力。本文基于长江中下游地区32篇关于秸秆还田对稻田温室气体排放的文献收集173组数据,利用Meta分析方法研究了3种秸秆还田方式下稻田CH_4和N_2O排放的特征,并估算出不同秸秆还田方式下稻田的全球增温潜势和净增温潜势。结果表明,CTS、NTS和RTS处理下稻田CH_4周年排放的效应值分别为0.76、0.37和0.68,稻田N_2O周年排放的效应值分别为0.44、0.36和0.52;在两熟制下,不同秸秆还田方式下稻田CH_4周年排放的效应值的大小为RTSCTSNTS,但N_2O周年排放的效应值的大小为RTSNTSCTS。在三熟制下,三种秸秆还田方式下稻田CH_4的周年排放的效应值的高低为CTSRTSNTS,而N_2O周年排放的效应值的高低为RTSNTSCTS。在相同的秸秆还田方式下,三熟制稻田温室气体周年排放的效应值都高于两熟制。此外,不同的还田秸秆种类影响稻田温室气体的排放;结合前期研究,估算出CTS、NTS和RTS处理下稻田的净增温潜势分别为12 375.55、11 232.36和15 982.87 kg CO_2-equivalent·hm~(-2)。因此,免耕秸秆还田是长江中下流地区稻田净减排条件下适宜的秸秆还田方式。