Response curves of seventeen woody species to soil factors along a riparian forest in northern Iran

The aim of this study was to determine type of response curves for seventeen woody species (10 tree and 7 shrub species) to soil factors in an intact riparian forest in Safaroud River in northern Iran using HOF function. Data were collected along transects established perpendicular to the water flow on both sides of the river. Results indicated different responses for different woody species. The most common were symmetricunimodal response curves and curves showing an increase in occurrence probability after a certain value in form of a plateau. Bimodal curves were four times more frequent in riverside than forest interior area. It seems that river flow disturbances through frequent floods effect on species tolerance and optimum in riversides.     

Quantitative Relationships between Predatory and Nonpredatory Animals in Freshwater Ecosystems

The ratios between the sizes of predators and prey have been estimated. On average, the linear sizes and body weights of aquatic predatory animals are approximately three and nine times greater, respectively, than those of nonpredatory animals. The biomass of predators in waters with different productivity levels is, on average, about 20% of the biomass of nonpredatory animals. However, the ratio between the biomasses of predatory and nonpredatory animals in the same water body may vary seasonally and annually and differ in different parts of this water body. The average numbers of predatory fish in ichthyocenoses are no more than 3% of the numbers of nonpredatory fish. The living space (individual range) of predatory fish is about 40 times larger than that of their prey. The relatively low numbers of predators in water bodies may be accounted for by the lower number of predatory species and their higher mortality at early developmental stages, compared to nonpredatory species.     

Relationships between sea-bed radionuclide activities and some sedimentological variables

Natural radionuclides (232Th, 226Ra, 40K) and 137Cs, coming from atmospheric radioactive fallout, have been measured in sea-bed sediments of the Bay of Cádiz (South Western Spain). In this report, multivariate analysis methods have been employed to study the relationships between the activities of the radionuclides and some sedimentological variables like granulometric facies, organic content and apparent density. The correlation functions found show that it is possible to determine, with a satisfactory degree of approximation, the granulometric facies of the sediments using only radiometric information.     

Frequency distribution of minimum distances between singing males in different chaffinch (Fringilla coelebs L.) populations as an indicator of habitat quality

The results of census mapping over nine nesting seasons have been used to calculate frequency distributions of minimum distances between male singing chaffinches. Comparison of these distributions shows consistent, high, and significant similarity of spatial structures within each population, despite considerable fluctuations in bird density (from 204 to 118 territories per hectare) and basic differences between spatial structures of different populations (two significantly different classes are distinguished). An approach to estimation of habitat quality by assessing the spatial structure of populations is proposed.     

Relationships between pikas (Ochotona, mammalia) and vegetation in Tuva

The burrowing and trophic activities of four pika (Ochotona) species proved to be reflected in the horizontal structure of the biogeocenotic cover. Zoophytochores ofOchotona daurica andO. pallasi pricei burrows correspond to previously described ameboid zoophytochores. Burrows of pikas provide for the growth of pea shrubs (Caragana bungei, C leucophloea), with the formation of specific plant groups under their crowns and on rubble dug out by pikas. In ecosystems of placers, zoophytochores are formed owing to the presence of pika food stores and lavatories, which are the main substrate for vascular plants first appearing among the stones. General ecological (and successional) series characterizing the overgrowing of placers is as follows: (1) separate spots of vegetation with poor floristic composition at the sites of pika food stores (stacklets); (2) groups of spots and simplest complexes; and (3) complex plant communities of pika colonies. Food stores of pikas in Tuva were analyzed.     

黑河流域产业结构与生态环境耦合关系辨识

产业结构作为人类作用于生态环境的主要环节．与区域资源、环境存在着显著的互动关系。在生态环境脆弱、水资源紧缺的西北干旱区内陆河流域,由于产业发展与流域生态环境及水资源的空间分布不相吻合．导致生态环境严重退化．目前亟需深入研究产业结构与生态环境的耦合关系。本文以黑河流域为典型研究区,通过建立生态环境质量及产业结构效益指标体系,对黑河流域上、中、下游的生态环境质量和产业结构效益作了综合评价,并对二者的耦合关系进行了定量辨识。结果表明：黑河流域产业结构效益自上游向下游在空间上呈倒“U”型,而生态环境质量与环境产业协调度沿河自上游向下游具有基本一致的变化趋势,都依次降低,说明现阶段黑河流域沿河自上游向下游,产业结构对生态环境的依赖性逐渐降低,而破坏性逐渐上升。     

Evaluation of land use change degree and ecological security in the Manas River Basin,Xinjiang, China

In this paper, we evaluate the extent of land use change and ecological security grades in the Manas River Basin, on the northern slopes of the Tianshan Mountains, from 1989–2002. Surveys were performed using Remote Sensing (RS) and Geographic Information System (GIS) means, and the relationship between land use change and ecological security was analyzed. The results are as follows: (i) the degree of land use change steadily increased in the Manas River Basin, and overall land use was in a state of development; (ii) From 1989–2002, the ecological security of the drainage basin generally improved somewhat, but deteriorated subsequently in some regions; (iii) the ecological security grade increased in regions with land use composite change extent values of 18–100, and ecological security grade improved from moderate warning in 1989 to early warning in 2002; and (iv) the cumulative areas of regions with relatively secure, and early-warning ecological security grade were ranked by land use degree in the order, V > IV > I > VI > III > II, showing that that regions with land use degree V (woodlands and grasslands) were important areas for ecological restoration and regeneration in this drainage basin, and that it was difficult to improve the ecological environment on sandy soils. We suggest that ecological security grades can be improved by increasing land use degree in regions where it is low.     

欧盟碳配额现货与期货价格关系及对中国的借鉴

基于欧盟碳市场配额现货与期货的发展经验和对我国统一碳市场建设的借鉴,本文以2005-2012年欧盟碳排放权交易体系(EU ETS)欧盟配额的现货和期货价格为样本研究二者之间的关系。本文运用单位根检验(ADF检验)的方法验证现货与期货价格的序列平稳性,并在序列平稳的前提下基于协整理论研究现货价格与期货价格的长期均衡关系,反映了二者间的静态关系。但短期内这一静态关系并不成立,反而表现出一定的动态性,短期价格的变动能够真实地反映市场需求,对价格的形成起着重要作用,因而采用向量误差修正模型重点研究二者间的短期动态关系。研究表明:1碳现货价格与期货价格间有着不同程度的影响,二者存在长期均衡,但短期内受市场特定因素的影响,二者又有所偏离;2期货价格反应灵敏,偏离均衡后调整速度快于现货,而且期货的滞后期价格对现货价格影响显著,这更加突显了碳期货的价格发现作用;3期货市场涉及了投资者对市场的预期和判断,较现货交易包含了更多的投机性,价格更为灵活,波动频繁,增加了市场风险。最后,根据结论对我国碳市场建设提出一些启示和建议:针对现货与期货价格之间的动态关系,应当积极开发和利用碳期货市场,通过期货的价格发现功能形成合理碳价,同时需要增强期货市场与现货市场的透明度,实现信息的传递与分享,最终实现期货市场对现货市场的补充和完善;为规避期货价格的波动性所带来的风险,需要建立一套完善的风险防控体系,在风险可控的前提下利用期货价格对市场进行预期,及时引导市场价格,形成完善的价格机制,为全国统一碳市场建设提供价格基础。     

Expansion and some ecological features of the wild boar beyond the northern boundary of its historical range in European Russia

During a historically observable period, profound and often irreversible changes in the faunal composition, distribution, and abundance of game animals were taking place throughout the territory of northern Europe. These changes were especially conspicuous in case of large mammals because of their large body size and roles in biocenoses and human economic activities. This paper deals with the results of monitoring the range and abundance of the wild boar and some ecological observations on this species at the northern limit of its distribution in European Russia.     

基于耦合协调度模型的河西走廊生态环境质量时空格局演化

以“丝绸之路”经济带上的河西走廊地区为研究对象,采用耦合分析法,构建环境承载力与生态弹性限度的耦合协调模型,在分析2001—2016年河西走廊生态环境承载力和生态弹性限度的基础上,探析河西走廊生态环境承载力与弹性限度的耦合协调度,评价生态环境承载力和生态弹性限度耦合协调阶段及区域生态环境质量水平,从区域和城市两个空间尺度分析生态环境耦合协调类型,为探索河西走廊生态环境可持续发展道路提供科学依据。结果表明:①2001—2016年,河西走廊生态环境承载力和生态弹性限度均呈现东南高、西北低的空间格局和缓慢波动上升趋势。②河西走廊生态环境耦合协调度呈现“东南高西北低,优劣破碎穿插”的空间格局特征,耦合协调度在0~0.5之间,生态系统处于低水平和拮抗耦合阶段,生态环境质量处于濒临失调阶段。③河西走廊生态环境承载力与生态弹性限度耦合协调度存在明显区域差异。河西走廊生态环境耦合协调度共分9个等级3个层次3个耦合协调阶段:高水平-磨合阶段区(良好协调、中度协调和初级协调区);中等水平-拮抗耦合阶段区(勉强协调、濒临失调和轻度失调区)和低水平区-低水平耦合阶段区(极度失调、严重失调和中度失调区)。④根据2001—2016年生态环境耦合协调状况将河西走廊五市分为4种耦合协调类型:高耦合协调增长型(张掖市、金昌市)、高耦合协调减少型(武威市)、中耦合协调增长型(嘉峪关市)和低耦合协调增长型(酒泉市)。各地区应因地制宜地制定发展战略,提高生态环境质量,推进生态环境持续协调发展。     

Relationships between spatial and temporal variabilities in airborne metal distributions in Won Ju City, Korea

The relationship between temporal and spatial factors in controlling the metal distribution characteristics was investigated using the monthly metal concentration data collected from four distinctive sampling sites (grassland, residential, commercial, and industrial site) of Won Ju City, Kang Won province for approximately 4-year periods between 1991 and 1995. In order to compare the relative role of spatial and temporal factors, two-factor analysis of variance (ANOVA) was applied to these data sets. For the application of this method, temporal factors were investigated in terms of both annual and seasonal basis. The results of our data analysis indicated several interesting aspects of metal-to-metal distribution behavior such that: (1) Pb, Fe, and Cu tend to exhibit strong variabilities in both spatial and temporal scale, (2) the distribution variabilities for Mn are almost negligible in both temporal and spatial scale, (3) Cd is more variable in temporal, rather than spatial, sense, and (4) Cr and Ni can exhibit more variable patterns depending on temporal scale selected for data analysis. On the basis of this study, the relative roles of spatial and temporal factors are described in relation to each other and to different metal species.     

Modelling the trade-off between fire and grazing in a tropical savanna landscape, northern Australia.

As savannas are widespread across northern Australia and provide northern rangelands, the sustainable use of this landscape is crucial. Both fire and grazing are known to influence the tree-grass character of tropical savannas. Frequent fires open up the tree layer and change the ground layer from perennials to that dominated by annuals. Annual species in turn produce copious quantities of highly flammable fuel that perpetuates frequent, hot fires. Grazing reduces fuel loads because livestock consumes fuel-forage. This trade-off between fire and grazing was modelled using a spatially explicit, process-orientated model (SAVANNA) and field data from fire experiments performed in the Victoria River District of northern Australia. Results of simulating fire (over 40 years) with minimal or no grazing pressure revealed a reduction in the shrub and woody plants, a reduction in grasses, and no influence on the tree structure given mild fires. While mature trees were resistant to fire, immature trees, which are more likely associated with the shrub layer, were removed by fire. The overall tree density may be reduced with continual burning over longer time periods because of increasing susceptibility of old trees to fire and the lack of recruitment. Increases in stocking rates created additional forage demands until the majority of the fuel load was consumed, thus effectively suppressing fire and reverting to the grazing and suppressed fire scenario where trees and shrubs established.     

The association between organochlorine and thyroid hormone levels in cord serum: a study from northern Thailand

It is now known that many organochlorines (OCs) act as endocrine disruptors, causing harmful effects on wildlife and humans. Several field and laboratory animal studies have reported that OCs cause adverse effects on thyroid hormone status. However, data regarding their effects on thyroid hormone status in humans are inconclusive. Because a developing fetus is especially sensitive to hormonal disruption by exposure to OCs, the adverse health effects on infants are of concern. The present study aimed to investigate the association between OC levels in maternal and cord serum, and the association between OC and thyroid hormone levels in cord serum. The study was performed with 39 mother-infant pairs from Mae Rim District of Chiang Mai Province, northern Thailand, who had normal delivery and full term gestation. Maternal blood was collected for measuring OCs and total lipids. Umbilical cord blood was collected for measuring OCs, total lipids, and thyroid hormones, including total thyroxine (TT(4)), free thyroxine (FT(4)), and thyroid stimulating hormone (TSH). 1,1-dichloro-2,2-di(4-chlorophenyl)ethylene (p,p'-DDE) had the highest level in all serum samples with a geometric mean of 1,191 ng/g lipids in maternal serum and 742 ng/g lipids in cord serum. The second highest level was that for 1,1,1-trichloro-2,2-di(4-chlorophenyl)ethane (p,p'-DDT), followed by 1,1-dichloro-2,2-di(4-chlorophenyl)ethane (p,p'-DDD). Levels of p,p'-DDE, p,p'-DDT, p,p'-DDD, and dieldrin in maternal serum were positively associated with levels in cord serum (r = 0.86, 0.77, 0.66, and 0.60, respectively; P<0.001). The important findings were that cord serum TT(4) levels were negatively associated with cord serum levels of p,p'-DDE (r = -0.37, P = 0.024), p,p'-DDT.3 (r = -0.33, P = 0.048), and 1,1-dichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethylene (o,p'-DDE) (r = -0.76, P = 0.019). These results therefore suggest that exposure to DDT and its metabolites during fetal development may cause some effects on thyroid hormonal status in infants.     

中国建设占用耕地数量与人口增长关系实证

采用经济计量分析方法通过观察1986-2006年中国建设占用耕地数量与人口增长之间的动态演进机制,提出两者之间的因果关系的假设,并进行了验证.研究结果表明我国建设占用耕地资源数量变化与人口增长具有协整关系,即两者之间存在长期均衡关系;建设占用耕地资源数量与人口增长之间相互作用的效果存在明显差异,建设占用耕地资源数量对人口增长带来的冲击响应强烈,而人口增长对建设占用耕地资源数量的冲击响应则相对较弱;进而验证建设占用耕地资源数量的变化与人口增长之间存在从人口增长到建设占用耕地数量变化的单向Granger因果关系,而从建设占用耕地数量变化到人口增长的Granger因果关系并不显著.因此,为协调"人口-(土地)资源"的关系,我国政府在加强人口和计划生育工作的基础上,应同时采取长期而非短期的策略,把"先补后占"、耕地转用许可制度等系列耕地保护政策与土地集约节约利用作为主要途径.     

Water quality of reclaimed water from treated urban wastewater in Chaobai River Basin,North China

The utilization of reclaimed water could be an efficient tool to alleviate water scarcity,especially for dry river augmentation.However,it is crucial to monitor water quality to ensure safety to human health and to avoid negative effects on the environment.Reclaimed water samples were collected bimonthly from May to November in 2010 in Chaobai River,and the physiochemical parameters were determined.The main results are as follows:The parameters exceeding the threshold value of the water guidelines are mainly nutrition related to nitrogen and phosphorus,which are known to increase the risk of eutrophication in surface waters.Additionally,nitrite and nitrate can be detrimental to human health.The majority of the parameters have a peaking concentration in May,whereas others either show significant temporal variation over the entire period or remain relatively constant in all four months.Correlation analysis shows that some parameters(pH,T and B) have no significant correlation with others,whereas significant positive correlation was found for Sr with EC and TDS,for CI with TDS,for Si02 with TP and for NO3-N with TN and a significant negative correlation between SO4 and Ba.According to principal component analysis,60.108%of the total data is represented by dominant solutes,and the second principal component with a percentage of 31.876 comprises parameters related to nitrogen.Subsequent cluster analysis of parameters identified four groups,which represent different compositions,and samples in May differ from others.     

Water quality of reclaimed water from treated urban wastewater in Chaobai River Basin,North China

The utilization of reclaimed water could be an efficient tool to alleviate water scarcity, especially for dry river augmentation. However, it is crucial to monitor water quality to ensure safety to human health and to avoid negative effects on the environment. Reclaimed water samples were collected bimonthly from May to November in 2010 in Chaobai River, and the physiochemical parameters were determined. The main results are as follows: The parameters exceeding the threshold value of the water guidelines are mainly nutrition related to nitrogen and phosphorus, which are known to increase the risk of eutrophication in surface waters. Additionally, nitrite and nitrate can be detrimental to human health. The majority of the parameters have a peaking concentration in May, whereas others either show significant temporal variation over the entire period or remain relatively constant in all four months. Correlation analysis shows that some parameters (pH, T and B) have no significant correlation with others, whereas significant positive correlation was found for Sr with EC and TDS, for Cl with TDS, for SiO₂ with TP and for NO₃–N with TN and a significant negative correlation between SO₄ and Ba. According to principal component analysis, 60.108% of the total data is represented by dominant solutes, and the second principal component with a percentage of 31.876 comprises parameters related to nitrogen. Subsequent cluster analysis of parameters identified four groups, which represent different compositions, and samples in May differ from others.     

Principles and issues in radiological ecological risk assessment

This paper provides a bridge between the fields of ecological risk assessment (ERA) and radioecology by presenting key biota dose assessment issues identified in the US Department of Energy's Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota in a manner consistent with the US Environmental Protection Agency's framework for ERA. Current radiological ERA methods and data are intended for use in protecting natural populations of biota, rather than individual members of a population. Potentially susceptible receptors include vertebrates and terrestrial plants. One must ensure that all media, radionuclides (including short-lived radioactive decay products), types of radiations (i.e., alpha particles, electrons, and photons), and pathways (i.e., internal and external contamination) are combined in each exposure scenario. The relative biological effectiveness of alpha particles with respect to deterministic effects must also be considered. Expected safe levels of exposure are available for the protection of natural populations of aquatic biota (10 mGy d(-1)) and terrestrial plants (10 mGy d(-1)) and animals (1 mGy d(-1)) and are appropriate for use in all radiological ERA tiers, provided that appropriate exposure assumptions are used. Caution must be exercised (and a thorough justification provided) if more restrictive limits are selected, to ensure that the supporting data are of high quality, reproducible, and clearly relevant to the protection of natural populations.     

基于MODIS数据的堵河流域生态指数变化及与气候因子的相关性分析

堵河流域是南水北调中线工程的重要水源区,流域的生态环境决定着南水北调的经济效益和水质状况.基于MODIS影像(2001～2017年)、数字表面模型(DSM)与气象数据,采用均值统计法、一元线性回归趋势法和相关分析法对堵河流域总初级生产力(GPP)、归一化差异植被指数(NDVI)、和蒸散发(ET)等生态指数的时空变化特征及其与气象因子的相关性进行研究,探讨堵河流域生态环境演变规律及其气候响应特征.结果 表明:(1)堵河流域多年月均GPP、NDVI和ET分别为1868.67 gC/(m2·month-1)、0.605和959.975 mm/month,植被覆盖率较高;多年年均GPP、NDVI和ET呈现相似的空间分布规律,堵河南岸值均高于北岸,竹溪河流域值均最低,最高值均位于神农架林区在内的高海拔区域.(2)年均GPP、NDVI和ET值总体呈波动上升的趋势,表明堵河流域的生态环境在向好的趋势发展;年内呈周期性单峰变化趋势,7月达到最大值;具有较强的季节性,夏季GPP、NDVI和ET值最大,冬季最小.(3)流域月均NDVI、ET和GPP之间均具有较强的正相关性,其中月均NDVI与月均GPP\ET的相关系数R2均为0.65,月均ET与月均GPP的R2为0.70.(4)流域月均GPP与月均降水的相关性强于月均气温,而NDVI、ET与气温的相关性均大于降水;GPP、NDVI和ET的变化与气温、降水呈现同期变化规律,NDVI、ET和GPP的变化对气候因子的响应不到一个月的滞后性.