Distribution of plants differing in attitude toward thermal conditions in communities of the timberline ecotone on Mount Iremel’, the Southern Urals

Specific features in the distribution of plant species differing in their attitude toward thermal conditions have been studied in communities of the present-day timberline ecotone on Mount Iremel’ in the Southern Urals. It has been shown that the distribution of such species is characterized by significant spatial nonuniformity. Elevation above sea level, local conditions in habitats located at the same altitudinal level, and specific features of mountain slopes account for 13–84, 5–30, and 0.4–14% of the total variance of test parameters, respectively. The abundance of plants changes nonlinearly along the altitudinal gradient, whereas changes in the species diversity of different plant groups have an almost linear pattern. Marked differences between plant communities with respect to the proportions of species differently responding to changes in thermal conditions have been revealed on all slopes in the upper part of the timberline ecotone, upon transition from the slopes proper to the plateau-like areas of intermontane depressions.     

The role of floods in the Long-term dynamics of geobiont and chortobiont communities on islands of the Kuibyshev Reservoir

Interannual changes in geobiont and chortobiont abundance on the islands of Kuibyshev Reservoir are largely determined by flood conditions, because the seasonal average abundance of many taxa is negatively correlated to the water level in May and June. Floods influence the abundance of these animals both directly and indirectly, through biocenotic connections and some aspects of behavior. Long-term positive trends are observed in the abundance of many species. The hypothesis is proposed that this increase in the abundance of geobionts and chortobionts is a consequence of adaptation processes in these communities, which are stimulated by the flood regime of the reservoir.     

崇南水陆交错带景观整体适应性评价与提升

水陆交错带存在自然和人文要素复合影响作用，其景观系统整体适应能力亟需提升。以崇明南部水陆交错带为研究对象，基于景观系统本底评价，借鉴景观特征评价（LCA）方法，探讨岛屿水陆交错景观整体适应性评价方法。从自然资源保护重要程度、土地资源利用适宜状况、环境安全压力显著特性3个子目标层，构建12个指标因子的评价体系；并进行要素层面和目标层面的适应性评价分析；确定研究区6类适应性特征分区，提出其景观资源适应性发展提升策略。研究为水陆交错带景观系统整合发展提供保护性开发的评价方法和决策支持路径。     

Response of three dominant shrubs to soil water and groundwater along the oasis-desert ecotone in Northwest China

The ecotone from oasis to desert is an important area for combating sandy desertification. Three dominant desert shrubs (Nitraria tangutorum, Calligonuum mongolicum, Haloxylon ammodendrori) were selected in Minqin Oasis, Northwest China, to determine the groundwater level; soil water potential; and change of the three shrubs in density, coverage, and biomass along the natural and seminatural oasis-desert ecotone (ODE), respectively. The results indicated that traits of desert plant interaction with the topsoil water and groundwater depth along the ODE play an important role in generating complex desert vegetation spatial dynamics. Some natural desert plant species with shallow root systems will distribute themselves according to distribution of topsoil water. Thus, the distribution of Nitraria tangutorum had a decreasing trend in distribution along ODE. Calligonuum mongolicum occurs in different trends in natural and seminatural ODE due to utilizing groundwater as well as topsoil water. Some plant species with deep roots, such as Haloxylon ammodendron, will show more degradation near oases and will exhibit an ascending trend along ODE. Therefore, it is of primary importance to protect the integrity of groundwater depth in order to protect the stability of the oasis-desert ecotones. The text was submitted by the authors in English.     

Arthropods and birds in the forest–tundra of Western Siberia and the edge effect

Over 2500 species of invertebrate macrofauna and over 177 species of avifauna live in the forest–tundra of the Lower Ob region and adjacent areas of the northern taiga and shrub tundra. About half of the invertebrate species of the study area are northern—mostly hypo- and hemiarctic—tundra species; the rest are boreal and arctomontane-boreal Holarctic and trans-Palearctic species. The anthophilic and aerobiont insect assemblages include many boreal forest forms. A total of 153 species have been observed nesting at the taiga–foresttundra boundary; 81 species have been observed nesting at the tundra–forest-tundra boundary. The avifauna of the forest–tundra becomes enriched with taiga species in floodplain forests and with tundra species on the flat interfluve, in areas of tundra and tundra-like wetlands. The forest–tundra of the Lower Ob region has no avifauna and entomofauna of its own and contains a mixture of taiga and tundra faunas. It has been found that the ecotone effect is not pronounced in the taxonomic composition of birds and insects in the forest–tundra, where only some particular groups (such as amphibiont insects) have increased abundance.     

巢湖水陆交错带生态服务价值梯度分析

基于巢湖水陆交错带1995、2000、2007和2013年4期遥感影像提取土地利用信息,参考前人的相关研究成果,测算研究区的生态服务价值。在综合研究区实际情况和相关研究基础上采用等距离缓冲带法,对研究区生态服务价值的梯度变化进行研究。结果表明:(1)各土地利用类型的梯度变化在不同时期有较为一致的变化趋势,在不同的缓冲带内都有1~2个贡献率较大的土地利用类型;(2)在研究期内各缓冲带生态服务价值处于基本平稳的状态,其中缓冲带1到缓冲带2的变化幅度较大;(3)从生态服务价值的空间分布来看,缓冲带1的生态服务价值始终最高,外层的缓冲带5和缓冲带6由低等级到中等级平稳过度,缓冲带3和缓冲带4则始终处在低水平;(4)林地和水域对生态服务价值的贡献率与距巢湖水陆边界的距离有显著的相关性,表明林地和水域对研究区生态服务价值的影响大。     

Populations of orchids at the northern limit of their distribution (Murmansk Oblast): Effect of climate

The effect of climatic conditions on the dynamics of 21 populations of 10 species of the family Orchidaceae at the northern limit of their range in Europe was studied between 1992 and 2004. The abundance of orchid populations proved to depend primarily on air temperature during the previous and current growing seasons.     

Influence of Hydrologic Conditions of the Lower Ob Floodplain on Reproduction in Coregonids

The influence of the water level in the period of the open river channel and the duration of lower floodplain inundation on the feeding conditions, abundance, and population state of coregonids in the Lower Ob was investigated. The long-term dynamics of catches of some coregonid species was analyzed and compared with changes in the hydrologic conditions in the floodplain. The relationship between basic hydrologic conditions in the Lower Ob (water level in the period of the open channel, the duration of the lower floodplain inundation), the coregonid population sizes, the state of spawners, and the size of catches is demonstrated.     

Structure and formation of conifer stands in the upper timberline ecotone on the North Chuya Ridge,Central Altai

The structure of Siberian stone pine (Pinus sibirica Du Tour.) and Siberian larch (Larix sibirica Ledeb.) stands and specific features of their formation have been studies in the forest-tundra ecotone on the North Chuya Ridge (2235–2475 m a.s.l.). Changes in the structure of these stands along the transition from the upper boundary of closed forests to the high-mountain tundra have proved to have an ambiguous pattern. Both tree species form mixed clusters of similar-aged trees in the lower part of the ecotone but grow singly, in scatters, in its upper part. The formation of conifer stands (tree clusters) in the lower part of the ecotone, on the slopes of the Aktru River valley, began during climate warming in the second half of the 19th century. The expansion of confers to its upper part took place markedly later, in the early 20th century (Siberian larch) or even in the 1930s (Siberian stone pine).     

Activity of Beavers as an Ecological Factor Affecting the Zooplankton of Small Rivers

The role of beavers in the transformation of small rivers is elucidated by analyzing the taxonomic and trophic structure of zooplankton in ponds differing in age, water flow rate, and the degree of overgrowing with higher aquatic plants. The building activity of beavers in the river system promotes the formation of biotopes of the ecotone type, in which the planktonic invertebrate community develops some features similar to or different from those of zooplanktonic communities from lakes and rivers undergoing anthropogenic eutrophication. The main distinctive feature of response to this activity in zooplankton is that its development reaches a plateau at the early and middle stages of succession, compared to that under conditions of anthropogenic eutrophication. For small rivers, the concept of zoogenic eutrophication (in addition to anthropogenic) is proposed.     

Changes in the structure and phytomass of tree stands at the upper limit of their growth in the Southern Urals

Relationships between stem diameter and phytomass of trees and their parts (single- and multistemmed growth forms) have been studied at different altitudinal levels of the present-day upper treeline ecotone on the Iremel’ Massif, the Southern Urals. The time course of changes in the structure and phytomass of birch–spruce stands during the past centuries has been reconstructed. It is shown that the expansion of forests to the mountains in this period has occurred against the background of rise in summer and winter temperatures and increase in the amount of solid precipitation in the Southern Urals.     

Assessment of the hunting of mammals using local ecological knowledge: an example from the Brazilian semiarid region

The hunting of wild animals remains a common activity in various parts of the world, especially in rural communities with poor socioeconomic conditions. To investigate patterns of mammal hunting, this study adopted a rural community located in semiarid Brazil as a model to test whether variables such as perceived abundance, activity period (day or night) and animal biomass could influence the consumption potential of mammal taxa. For this study, a checklist/interview technique using 32 photographs of mammals recorded in the region and two photographs of species that did not occur in the region, which acted as “control” species, was used, in addition to other visual stimuli and free lists. All species presented in the photographs, with the exception of the “control” species, were recognized as occurring in the region. Fourteen species were cited as being those most hunted locally. The species cited as most hunted had an average perceived abundance higher than the group of the least-hunted species. However, there was no significant relationship between hunting of a species and its locally perceived abundance. No significant difference in hunting pressure between diurnal and nocturnal species was found, nor was a relationship between animal biomass and hunting pressure observed. Our findings suggest that perceived abundance is an important factor for choosing a resource fauna, but other factors such as intended use, meat flavor and vulnerability to hunting, among others, may influence the potential use of a species.     

青藏铁路沿线北段植被物种丰富度及盖度的动态变化

通过青藏铁路沿线北段西大滩至唐古拉山北坡范围内植被样带的抽样调查,对植物物种丰富度（〖WTBX〗S〖WTBZ〗）、植被盖度由北至南的动态变化特征以及两者的相关关系进行了分析。结果表明：（1）在青藏沿线北段高海拔地区,由北至南植物物种丰富度呈逐渐升高的趋势,1m2样方平均物种数量由沿线北部样带的5或6种,逐渐升高至南部样带的9或10种。多重比较表明,相邻或相近的植被样带间单位面积物种丰富度多差异不显著,而当样带间距加大时,则表现出显著性差异。（2）由北至南各样带1m2样方平均盖度呈不规则的动态变化,多重分析表明,多数样带间1m2样方盖度间存在显著差异,说明植被盖度与物种丰富度相比更多地受到地形、土壤理化性质等小环境因素的影响。（3）研究区域北部各样带1m2样方平均盖度与物种丰富度呈现较显著的正相关关系,且多以乘幂指数方程拟合精度较高。而在研究区域南部,则未表现出显著的相关关系,这是因为这些样带中群落盖度主要受少数优势种盖度所控制,而与群落物种数量相关性不大。最后,提出今后需要加强青藏铁路沿线高寒地区植被分布格局及其环境解释的相关研究,以便深入分析区域植被分布的格局和成因。     

Economic Conditions,the Policy Cycle,and Media Visibility of Environmental Organizations

The extent to which social movements have access to the news media has important implications on the capability of social movements to communicate with and garner support from the public. Factors that shape movement organizations' media visibility thus deserve scholarly attention. This article deals with news coverage of environmental movement organizations (EMOs) in Hong Kong and focuses on the impact of economic conditions, the policy cycle, and the number of EMOs in society on media visibility of EMOs. Analysis of a data-set constructed based on archival data and official statistics illustrates that all three factors influence media visibility of EMOs through media attention to environmental issues, while the number of EMOs and economic conditions also affect media visibility of EMOs directly. In-depth interview data are then used to supplement the quantitative analysis by showing how movement activists perceive and respond strategically to the structural factors. Theoretical implications of the findings are discussed.     

中国植被覆盖度时空特征及其影响因素分析

植被覆盖度是衡量植被生长状况和描述生态系统环境的重要指标,以2001～2018年MODIS NDVI数据集为基础,采用混合像元二分模型,计算中国植被覆盖度(FVC),分析中国年FVC的时空变化特征,探讨FVC对气候和人类活动干扰的响应机制,以及人类活动对FVC影响的未来变化特征。结果表明:(1)中国FVC整体呈上升趋势;西北的年均FVC明显低于东南的年均FVC;除青藏高原FVC为下降趋势外,其余均呈上升趋势,且该趋势具有一定持续性。(2)各植被类型中,混交林的年均FVC最高,草原的年均FVC最低;而农作物变化率最大,混交林变化率最小,且未来将由改善转为退化趋势,其余均表现为持续性改善。(3)中国FVC与气温呈负相关、与降水呈正相关,且降水对FVC的影响强于气温,表明降水是影响FVC变化的主要因素。(4)中国人类活动对FVC的影响程度整体表现为增强趋势,未来人类活动影响力以反向持续性为主。表明未来18a中国FVC受人类活动的影响有所下降。     

可持续交通消费的接受和使用行为研究——基于上海市汽车共享的调查

汽车共享作为中国新兴的可持续交通方式,如何成功的使消费者接受和使用,是研究的关键挑战。本文基于UTAUT2模型,选择上海市居民作为调查对象,发现价格价值对行为意向影响最大,其次为享乐动机、努力期望、绩效期望和便利条件,社群影响对行为意向影响不显著;行为意向和便利条件对使用行为有显著正面影响,便利条件对使用行为影响更大。进而,使用个人特征为调节变量(是否有私家车、网约车经验和婚姻状况)验证对模型路径的影响,绩效期望对行为意向的影响受到是否有车、网约车经验和婚姻状况三个因素的调节,无车、无网约车经验与未婚的受访者调节效应更强;便利条件对行为意向和使用行为的影响同时受到是否有车单个因素的调节,无车者的调节作用更强;价值价格对行为意向的影响受到婚姻状况的调节,未婚者的调节效应更强;行为意向对使用行为的影响受到是否有网约车经验的调节,无网约车经验的调节效应更强。基于汽车共享服务发展初期的市场调查,本文建议汽车共享企业应提前布局服务网络,扩大会员数量,宣传它与私家车相比的成本优势和共享的价值观,获得细分市场。     

社会资本对农户保护性耕作技术采用的影响及区域差异研究——基于技术认知的中介效应分析

利用黄土高原1 237户农户的调查数据，以少免耕技术为例，分析了社会资本5个维度对黄土高原农户保护性耕作技术采用的影响，并检验了技术便利性认知、技术效果认知和技术风险认知的中介效应。结果表明，社会资本和技术认知对农户少免耕技术采用的影响存在明显的区域差异，其中山西省农户的社会信任、社会参与、社会声望和社会规范对农户少免耕技术采用有直接的正向影响；技术便利性认知在社会参与、社会声望和社会规范对技术采用的影响发挥了中介效应；技术效果认知在社会声望对技术采用的影响中发挥了中介效应；技术风险认知在社会信任、社会声望和社会规范对技术采用的影响中发挥了中介效应。陕西省农户的社会信任和社会规范对少免耕技术采用有直接的正向影响；技术便利性认知在社会信任和社会规范对技术采用的影响中发挥了中介效应；技术效果认知在社会信任对技术采用的影响中发挥了中介效应；技术风险认知在社会信任和社会规范对技术采用的影响中发挥了中介效应。甘肃省农户的社会网络、社会声望和社会规范对少免耕技术采用有直接的正向影响；技术便利性认知在社会规范对技术采用的影响中发挥了中介效应；技术风险认知在社会网络和社会规范对技术采用的影响中发挥了中介效应；技术效果认知为完全中介。     

农牧交错区生态环境建设与可持续农业发展研究

我国北方农牧交错区的地理分布特点，决定了它在我国农业生态上举足轻重的地位。面对日益严峻的环境问题，加大农牧交错区生态环境建设力度对改善该区生态环境和实现农业可持续发展具有十分重要的作用。针对农牧交错区面临的主要生态问题，提出了该区生态环境建设及实现农业可持续发展的基本对策。     

The Role of Micromycetes in the Phytotoxicity of Crude Oil-Polluted Soils

The microbe–plant interaction in soil under crude oil pollution was studied in Perm oblast, the Cisural Region. In the rhizosphere of plants growing in the oil-polluted soil, an increased abundance of nonsymbiotic saprotrophic micromycetes was recorded. Under conditions of crude oil pollution, the development of these microorganisms in the rhizosphere proved to have a strong adverse effect on the plants due to production of mycotoxins.     

Structure and dynamics of marginal Gymnadenia conopsea (L.) R. Br. (Orchidaceae) populations on limestones in the northeast of European Russia

Data are presented on the abundance, structure, and dynamics of hemipopulations of G. conopsea protocorms and autotrophic individuals at the northern boundary of the species range. The dynamics of ontogenetic structure of G. conopsea cenopopulations have a fluctuating pattern. Their response to adverse weather conditions is manifested in short-term reduction of density and increase in cenopopulation ageness in subsequent years. Deterioration of growing conditions in a series of ecotopes is accompanied by an increase in the proportion of young individuals, which allows the species to level off the impact of adverse weather factors on population size.