川滇黔接壤区经济非均衡性的边界效应

以区域经济学为基础,选择基尼系数来研究川滇黔接壤地区的区域经济非均衡发展水平和空间分布特点。通过Chow检验,发现川滇黔接壤地区各县/市间存在结构性变化,行政边界阻碍了省间各县/市经济差异的缩小速度。运用Barro回归方程对川滇黔接壤地区1995—2008年经济非均衡性的边界效应进行了定量测定,研究发现虽然行政区边界对...     

卫生垃圾填埋场边界的地电特性研究

研究卫生垃圾填埋场边界的地电特性,界定卫生垃圾填埋场边界有助于场地环境的维护和管理,采用电阻率二维层析成像技术中的3种装置排列(测深、温纳、偶极-偶极)对小型卫生垃圾填埋场模型进行对比测量,通过电阴率二维层析成像技术对填埋场边界的地电特性进行分析研究.研究结果表明,在测深和温纳两种装置排列,不能进行精确定位;而偶极-偶...     

欧盟碳边境调节机制的影响与应对分析

欧盟碳边境调节机制（CBAM）是当前国际上应对气候变化领域讨论的热点议题。欧盟委员会于2021年7月14日发布了CBAM草案,计划从2023年起逐步实施CBAM,并于2026年起正式对欧盟进口的部分商品征收碳边境调节税,这一举措引起了国际社会的强烈反响。本文对欧盟CBAM对全球和中国的影响进行了系统分析,结果表明： CBAM对全球减排的作用较小,中国碳密集产业将遭遇欧盟等国际市场竞争挤压,可能推进中国碳价上涨,建议要加强跟踪评估与开展储备研究,通过深入参与和引领国际标准与规则制定、全面发展低碳技术和产品、完善碳排放权交易制度、研究开征碳税等积极主动做好应对工作。     

Breeding birds in short-rotation coppices on farmland in central Sweden—the importance of Salix height and adjacent habitats

Plantations of short-rotation coppice (SRC) have a potential for being a useful measure to stop the ongoing impoverishment of farmland biodiversity by increasing structural diversity, and decreasing cultivation intensity and use of pesticides in intensively managed farmland landscapes. The aim of this study was to investigate the relative importance of the structure of the plantation and composition of adjacent habitats for breeding birds in 41 SRCs (meansize±S.E.=9.4±1.6 ha). Mean number of species per ha in the SRCs was 2.8±0.3 species and there were more farmland birds (32 species, 808 territories) than forest birds (22 species, 400 territories). A major result of the present study was the strong influence of adjacent habitats on bird community composition (18 of 22 analysed species affected). There were large differences in bird communities between forest-bordered and open-bordered sites, but occurrence of residual habitats (i.e. other habitats than forest, pastures, shrub areas and arable fields) was also associated with occurrence of several species. The second factor of major importance for the bird fauna was the height of the plantations. Most species (14) were associated with tall plantations (>2 m), seven species were associated with plantations of intermediate (1–2 m) height, and six species were associated with plantations of low height (<1 m). A comparison of ecological traits between species classified as preferring SRC and species classified as avoiding SRC suggests that nest height was the only ecological character associated with a preference for Salix habitats, i.e. species with nests on the ground or in shrubs were more abundant in Salix habitats than in farmland landscapes in general. However, a broad spectrum of species was found in the SRCs and many of these seemed to be dependent on habitat features outside the plantations. Planting of Salix in intensively managed farmland plains will have positive effects on bird diversity by increasing the structural diversity of the landscape. In contrast, plantations on infields in forest-dominated landscapes will have negative effects, since the mosaic structure (i.e. mixture of open and forested habitats) positive for most farmland birds will disappear, and Salix plantations favour relatively few forest species. Additionally, Salix could be planted along sharp edges between coniferous plantations and open farmland in order to increase the complexity of the ecotone in intensively managed forest-farmland landscapes.     

边境碳调节对中国EITE产业竞争力和碳泄漏的影响

碳市场碎片化状态使各国碳排放因减排力度差异而消长,不仅造成碳泄漏风险,同时对减排国家经济特别是排放密集产业的国际竞争力产生负面冲击。本文建立多区域多部门CGE模型,设计4种边境碳调节政策,模拟分析其对我国的福利、碳泄漏和出口型排放密集产业(EITE)竞争力产生的政策效应。研究显示,我国制定边境碳调节政策,既要考虑碳关税也要考虑出口返还,前者有利于改善我国的福利水平,后者可以收到抑制碳泄漏和保持EITE产业国际竞争力的效果,因而有必要把边境碳调节政策纳入我国碳市场制度设计。无论从产出还是贸易来看,我国EITE产业中的非金属矿、有色金属、钢铁产业在边境碳调节政策影响下,面临来自日本和亚洲其他国家的竞争压力,双方的碳泄漏和产业竞争力呈现此消彼长的动态变化。在我国碳市场建设过程中,边境碳调节政策与拍卖相结合,有利于在实现碳减排目标和维护产业竞争力之间实现平衡。     

Comparison of Diuron degradation by direct UV photolysis and advanced oxidation processes

The rates of Diuron elimination by some advanced oxidation processes (AOPs) such as Fe(III)/UV, Ferrioxalate/UV, Fe(III)/H(2)O(2)/UV, Ferrioxalate/UV/H(2)O(2) and Fe(III)/H(2)O(2) have been compared. Experiments have been conducted at pH=2.3+/-0.1 with a batch reactor equipped with a low-pressure mercury lamp emitting mainly at 253.7nm. Data obtained under the following experimental conditions ([H(2)O(2)](0)=10(-3)M, [Diuron](0)=5x10(-5)M and [Fe(III)](0)=10(-3)M) have shown that rates of Diuron oxidation were higher with the systems Fe(III)/H(2)O(2)/UV and Ferrioxalate/UV/H(2)O(2) than with Fe(III)/UV and Fe(III)/H(2)O(2). On the other hand, Fe(III)/UV was found to be very efficient in mineralization of Diuron solution in comparison to direct UV photolysis. The experimental results showed that radical ()OH is the major pathway in the process of Diuron degradation.     

Analysis of chemical contamination within a canal in a Mexican border colonia

This study examines urban pollution within Derechos Humanos, a colonia popular in Matamoros, Tamaulipas, Mexico. General water quality indicators (coliform bacteria, total dissolved solids, ecologically relevant cations and anions), heavy metals (copper, lead, nickel, zinc, iron and cadmium), and volatile organic compounds (benzene, toluene, ethylbenzene, styrene, and dichlorobenzene and xylene isomers) were quantified within a wastewater canal running adjacent to the community. Water samples were collected at multiple sites along the banks of the canal and evidence of anthropogenic emissions existed at each sampling location. Sample site 2, approximately 10 m upstream of the colonia, contained both the widest range of hazardous pollutants and the greatest number exceeding US Environmental Protection Agency surface water standards. At each sampling location, high concentrations of total coliform (> 10(4) colonies/100 mL sample), lead (ranging from 0.05 to 0.40 mg/L), nickel (levels from 0.21 to 1.45 mg/L), and benzene (up to 9.80 mg/L) were noted.     

A COMPREHENSIVE STUDIES ON THE BORDER OF THE EASTERN PARTS OF AREOGRAPHY OF MICHELIA YUNNANENSIS

This paper studies the morphological taxonomy, origination,ecological environment, floristic geography, community, regeneration,biomass.seed character,breeding and their biomass.and the relationship of the relative growth in the yearing seedling of Michelia yunnunensis, especially in the border of the eastern parts of the areography of Michelia vannanensis.