Latitudinal Gradients of Trophics in Ural Macrolepidoptera: The Role of Food Quality

The Macrolepidoptera fauna of the Urals, from the southern to the northern boundary of the forest zone (i.e., from the forest–steppe of the Southern Urals to the forest–tundra of the Polar Urals) has been analyzed. It has been demonstrated that the proportion of Lepidoptera feeding on woody plants, including evergreens, increases in this direction. Among the Heterocera, the proportion of species feeding on graminoids decreases; in the Polar Urals, none of these species is specialized. The food spectrum is particularly variable in noctuids and almost invariable in geometrids and Rhopalocera. It is assumed that foods with a low nutrient value (grasses, mosses, lichens, plant debris, wood, and roots of various plants) prevent Macrolepidoptera species from spreading in the Subarctic region. In the Polar Urals, multiyear developmental cycles and wintering at the larval stage are related to feeding on these types of food.     

基于多元数据的景观格局演变及其影响因素——以流沙河流域宜东段为例

利用1985年和1994年两期土地利用现状图及2003年遥感资料，在ArcGIS 9．0平台上，选取多样性、均匀度、破碎度、分离度和分维数等指数，分析了流沙河上游汉源县宜东乡的景观格局演变特征及其影响因素。结果表明，景观整体多样性指数和均匀度指数增大，优势组分有林地对景观的控制作用不断减弱；景观整体破碎度增大，斑块间离散度增大，景观形状变得较为复杂。影响因素分析表明，集镇和主要公路的影响使得其周围景观的分布以人为景观旱地为主。地形因素中，居民点、水田在坡度15^o以下区域和平地、阴坡上广泛分布；有林地、灌木林和荒草地等景观在15^o以上坡度级分布较广，其中有林地阴坡分布稍高于其余坡向，灌木林分布阳坡多于阴坡，旱地在半阳坡出现分布峰值。     

江汉平原耕地数量变化驱动机制分析--以仙桃市为例

江汉平原历来是我国重要的商品粮生产基地，保留一定的耕地数量对保障我国粮食安全具有重大意义。因此，研究其耕地变化的驱动因子使具有实际意义。文章以仙桃市为例，借助统计分析软件SAS，运用主成分析分析方法，分析了其1990-2002年耕地的数量变化及其驱动因子，并基于可持续发展理论提出了仙桃市耕地可持续利用的对策。     

Functional Isomorphism of Ecosystems and Its Significance for Ecological Prognosis

A concept concerning the functional isomorphism of natural ecosystems as a factor modulating climatogenic changes in the soil–plant cover is proposed. On an empirical basis, production and destruction types of isomorphism are distinguished, which differ in their prevailing influence on the dynamics of zonal and regional ecosystems in the boreal and subboreal belts.     

Biochemical Changes in Decomposing Leaves of Mangroves

Nylon bags containing yellow leaves of Rhizophora apiculata and Avicennia marina, were immersed for 80 days from August to October, 1996. the decomposing leaves were collected every 10 days and analysed for dry weight loss and six biochemical parameters: tannins, total amino acids, total sugars, total nitrogen, total lipids and fatty acid profile. the leaf weight initially decreased very rapidly by about 50% of the start in two species of mangroves within 10 days. Similar changes were observed with tannins, total amino acids and sugars. However, the concentration of nitrogen increased significantly with decomposition. There was no significant change in total lipid and fatty acid profile. the highest concentration of fatty acid in the decomposing leaves was palmitic acid (16:0). Unsaturated fatty acids such as, 18:1 w7c and 18:1 w9c were found to be present in decomposing leaves of both species.     

Climate changes and overstory recruitment of larch at the northern timberline in the Yamal Peninsula

Studies on overstory recruitment of the Siberian larch (Larix sibirica Ledeb.) in open larch forests depending on the time of seedling establishment (1880–1980) have been performed in the northern timberline ecotone on the Yamal Peninsula. Two periods of active larch establishment have been revealed: from 1900 to 1935 and from 1950 to 1970. A comparison of these data with the results of instrumental observations on temperature and precipitation has shown that the overstory recruitment of larch in valleys of northern rivers is largely dependent on July air temperatures in the first years of tree life, when seedlings grow 10–20 cm high.     

保定地区PM2.5中重金属元素的污染特征及健康风险评价

为了解保定市大气环境中PM_2.5中重金属的污染特征及其健康风险,在保定市设立观测站点,利用中流量颗粒物采样器对保定市大气PM_2.5进行了连续昼夜采集,并使用微波消解-电感耦合等离子质谱法分析了样品中的V、Cr、Mn、Co、Ni、Cu、Zn、As、Cd和Pb等10种重金属元素的质量浓度.结果表明,保定市大气PM_2.5浓度范围为16.84~476.19 μg·m^-3,采样期间有65d高于我国《环境空气质量标准》（GB 3095-2012）中的二级标准,超标率为54.2%.保定市PM_2.5中重金属元素的浓度变化趋势为：除Ni、Mn和Co外,夜间浓度略大于日间;大部分重金属元素秋冬季浓度大于春夏季.富集因子分析可知,保定市Cu、Zn、Pb、Cd主要来自于人为源,特别是受到交通源的影响较大.健康风险评估结果表明,保定市大气PM_2.5中的重金属污染的非致癌风险较小,致癌风险主要是As、Cr、Cd和Co,且成年人的致癌风险大于儿童.     

Changing institutions for environmental policy and politics in New Era China

ABSTRACT

The evolution of Chinese environmental policy and politics can be better understood in the broader context of institutional changes that have taken place since the late 1970s. In this study, an analytical framework was established to analyze how overall institutional changes were reflected in the roles of relationships between governmental and non-governmental actors engaged in environmental governance. Institutional changes were observed at three levels: informal institutions (cultural traditions, and political ideology); formal institutions (the polity, political system, property rights, and judiciary); and governing mechanisms (structures, regulatory approaches, and incentives). This analysis of interactions between institutional changes and the changing environmental process explained not only the drives and constraints behind China’s environmental policy evolution so far but also shed light on future challenges and opportunities.     

Evolution of the landscape as a response of a demographic change. A case study in the Duero riverside,Spain

The Arribes del Duero area, in western Spain, at the border with Portugal, is suffering a drastic change in the landscape, as a response of the diminution of population. Traditional tasks related to agriculture have been abandoned, and heavy sheep farming on the area is provoking the impoverishment of soils. The effect derived from these actions is the disintegration of the terraces, which are one of the major attractions for tourists visiting the region. We propose that incentives for local people could help to develop those traditional labours to recover the landscape, together with the promotion of immigration of families with school-age children, could bring back the economy to the area.     

中国农业发展与环境变迁

我国农业历史悠久,农业人口众多,人类活动尤其是农业发展对地理环境的影响极大。我国地理环境在时间与空间上都有很大差异。我国的环境变迁是自然条件与人类活动相互作用的结果。有些环境变化是“积极的”,如土地开发与绿洲建设、水利与灌溉、作物与家畜驯化、平原森林的营造等等,但更多环境变化是“消极的”,如旱灾、洪涝灾害、流沙、盐渍化、森林破坏、动物灭绝、土壤侵蚀、山地灾害等等。当地理环境利用得当时,积极的环境变化将占主导;但若利用不当或利用过度,消极的环境变化将最终占优势。