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Chinese Chemical Letters 2014年第11期25卷 1479-1484页

作者： Sheng-Jian Jia Da-Ming Du School of Chemical Engineering and environment Beijing Institute of Technology

Enantioselective chlorination of b-keto esters and amides catalyzed by squaramide-linked bisoxazoline ligand–Cu（OAc）2complexes was investigated. The corresponding chlorinated products were obtained in excellent yields with moderate enantioselectivities. The effect of solvent, temperature, Lewis acid, and ligand structure on the reaction is discussed. This was the first investigation of catalytic asymmetric achlorination of b-keto amides. This study has highlighted that a simple chiral squaramide–oxazoline with cheap Cu（OAc）2 H2 O complexes can catalyze this chlorination.

关键词： Asymmetric catalysis Bisoxazoline Squaramide Chlorination b-Keto esters

Diel and seasonal variation of methane and carbon dioxide fluxes at Site Guojiaba, the Three Gorges Reservoir

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Journal of environmental Sciences 2013年第10期25卷 2065-2071页

作者： Shangbin Xiao Yuchun Wang Defu Liu Zhengjian Yang Dan Lei Cheng Zhang Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges University institute of Earth environment Chinese Academy of Sciences Department of Water environment China Institute of Water Resources and Hydropower Research College of Resources and environment Sciences Hubei University of Technology

In order to investigate the CH4 and CO2 fluxes across the water-gas interface and identify their controlling factors, four diel field campaigns and one monthly sampling campaign during June 2010-May 2011 were carried out at a site near the Three Gorges Dam, China. The averaged CH4 and CO2 fluxes across the air-water interface from the site were much less than those reported from reservoirs in tropic and temperate regions, and from the natural river channels of the Yangtze River. CH4 Fluxes at the site were very low compared to most other reservoirs or natural lakes. One of the most important reasons may be due to the oxidation of CH4 in the water column owing to the great water depth and high DO in water in the Three Gorges Reservoir. The averaged monthly CH4 and CO2 fluxes at the site during the observation year were 0.05 mg/（m^2·hr） and 104.43 mg/（m^2·hr） respectively with the maximum occurred in July 2010. The monthly CO2 fluxes during the observation year were positively correlated to the surface water temperature, and negatively correlated to the air pressure and the surface water pH. The CO2 flux showed a positive correlation with DOC to some extent, although not significantly, which indicated that allochthonous organic C was a major source of CO2 and biogeochemical processes in this reservoir were C-limited. The significantly positive correlation between the reservoir outflow and the seasonal gas flux indicate the disturbance condition of the water body dominated the seasonal gas emission.

关键词： diel flux seasonal flux methane and carbon dioxide emission the Three Gorges Reservoir methane oxidation environmental factors reservoir outflow

A novel synthesis of nitroform by the nitrolysis of cucurbituril

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Chinese Chemical Letters 2015年第3期26卷 365-368页

作者： Hong-Yan Lu Jia-Rong Li De-Li Yang Qi Zhang Da-Xin Shi Chemical Engineering and environment Beijing Institute of Technology

Cucurbituril has a high symmetry and rigid *** cucurbit[6]uril（CB[6]） was nitrolyzed with the mixed solution of acetic anhydride in fuming nitric acid,nitroform（NF） was *** also can be obtained by the nitration of both CB[5,7,8].This nitration procedure provides a lower risk,inexpensive,new preparation of nitroform,and the reaction condition of this new method is very mild.

关键词： anhydride inexpensive acetic symmetry rigid oligomer supramolecular hexane condensation solubility

Application of pre-emergence herbicides in poplar nursery production

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Journal of Forestry Research 2015年第1期26卷 143-151页

作者： Verica Vasic Sasa Orlovic Predrag Pap Branislav Kovacevic Milan Drekic Leopold Poljakovic Pajnik Zoran Galic institute of Lowland Forestry and environment University of Novi Sad

In addition to pests and diseases, weeds are a major problem in poplar nursery production. The possibilities of herbicide application in juvenile poplar growth were researched, taking into account that weeds are one of the main limiting factors. The following pre-emergence herbicides were tested： acetochlor, S-metolachlor, metribuzin,oxifluorfen, and dimethenamid during two vegetation seasons at two locations, which differed by the soil physicochemical characteristics. The study results show that the number of weeds on sample plots was significantly reduced by the tested herbicides when compared to control plots. The highest reduction in the number of weeds was achieved using the herbicides acetochlor and metribuzin. However, metribuzin showed a phytotoxic effect on sandy soil. Metribuzin application is recommended only on the soils with higher contents of organic matter, where the phytotoxic effect was absent. Acetochlor, S-metolachlor, oxifluorfen, and dimethenamid were not phytotoxic to poplars and can be used for weed suppression in the production of poplar plants.

关键词： Poplar weeds Weed management Herbicides Phytotoxic effects

Forest structure and anthropogenic pressures in the Pachmarhi biosphere reserve of India

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Journal of Forestry Research 2015年第4期26卷 867-874页

作者： Chandra Prakash Kala Ecosystem & environment Management Indian Institute of Forest Management

A critical first step in establishing biosphere reserves--under the Man and Biosphere Programme of UNESCO--is to generate baseline information for future courses of action. The present study aims to assess the structure and composition of forests--along with anthro- pogenic pressures mounting on these forests in the buffer zone of one such biosphere reserves--the Pachmarhi bio- sphere reserve of India. The quadrat method was employed for sampling vegetation, and information on anthropogenic pressures was collected by conducting interviews with local people and forest officials and collecting it from secondary sources. A total of 39 tree species were sampled in 82 quadrats; of these 26 tree species were in standing stage, 25 in sapling, and 35 in seedling. Chloroxylon swi- etenia emerged as the most dominant tree species having highest importance value index, followed by Tectona grandis, Terminalia tomentosa, and Hardwickia binata. Nine tree species and their saplings, including Sterculia urens and Terminalia arjuna, were exploited so badly that they were only found in the seedlings stage. The unavail- ability of standing trees of 12 important tree species including Aegle marmelos and Phyllanthus emblicaindicates the intensity and gravity of anthropogenic pres- sures on these important tree species. If the present anthropogenic pressure continues, which has inhibited the regeneration of several tree species, then substantial neg- ative ecological and societal consequences can be expected.

关键词： Pachmarhi biosphere reserve Tropicalforest Forest composition Forest structure Regeneration Anthropogenic pressures

Geographical Space Development Zone Classification:An Essential Guide for Transformation of Mountain Resource Cities

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Chinese Geographical Science 2015年第3期25卷 361-374页

作者： ZHANG Jifei DENG Wei LIU Shaoquan institute of Mountain Hazards and environment Chinese Academy of Sciences

Sustainable development of mountain areas and resource cities has been a significant issue worldwide. Transformation of mountain resource cities is facing tremendous difficulties. In the context of National Major Function-oriented Zone Planning raised to a national strategic level in China, it is important to effectively implement the planning by studying geographical space development zone classification of prefecture- and county-level cities based on their major function orientation. This research is even more critical for the transformation of mountain resource cities. In this study, we evaluated geographical space development suitability, and classified geographical space development zones for Dongchuan Distric in Kunming City of Yunan Province, China, a typical mountain resource city. A quantitative grid-based evaluation was conducted using key-factor identification and restrictive-supportive comprehensive index determinati based on a geographic information system framework with different source data. The results included a classification of geographical space of Dongchuan into five types: the prohibited development zone, the inappropriate development zone, the controlled development zone, the moderate development zone and the preferential development zone. The distribution characteristics of geographical space development zones showed that the proportion of the prohibited development zone is the highest, while that of the other four development zones is comparatively lower and significantly fragmented. The geographical space development suitability is greatly controlled by the geomorphic pattern. Although Dongchuan is extremely restrained in terms of suitable geographical space for industrialization and urbanization, it still has the certain preferential and moderate development zones with an area of 207.81 km2 with large parts being concentrated and contiguous, which makes these areas the most favorable for development. Only by adapting to this reality and im

关键词： geographical space development suitability mountain resource city transformation of resource cities

Soil microbial community composition and its driving factors in alpine grasslands along a mountain elevational gradient

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Journal of Mountain Science 2016年第6期13卷 1013-1023页

作者： CUI Hai-jun WANG Gen-xu YANG Yan YANG Yang CHANG Rui-ying RAN Fei institute of Mountain Hazards and environment Chinese Academy of Sciences

Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soil microbial community of this type of vegetation in response to environmental change. Using phospholipid fatty acids （PLFA）, we investigated soil microbial community composition along an elevational gradient （3094-4131 m above sea level） on Mount Yajiageng, and we explored the impact of plant functional groups and soil chemistry on the soil microbial community. Except for Arbuscular Mycorrhizal fungi （AM fungi） biomarker 18：2ω6,9 increasing significantly, other biomarkers did not show a consistent trend with the elevational gradient. Microbial biomass quantified by total PLFAs did not show the elevational trend and had mean values ranging from 1.64 to 4.09 ktmol per g organic carbon （OC）, which had the maximum value at the highest site. Bacterial PLFAs exhibited a similar trend with total PLFAs, and its mean values ranged from 0.82 to 1.81 μmol （g OC）-1. The bacterial to fungal biomass ratios had the minimum value at the highest site, which might be related to temperature and soil total nitrogen （TN）. The ratios of Gram-negative to Gram-positive bacteria had a significantly negative correlation with soil TN and had the maximum value at the highest site. Leguminous plant coverage and soil TN explained 58% of the total variation in the soil microbial community and could achieve the same interpretation as the whole model. Other factors may influence the soil microbial community through interaction with leguminous plant coverage and soil TN. Soil chemistry and plant functional group composition in substantial amounts explained different parts of the variation within the soil microbial community, and the interaction between them had no impact on the soil microbial community maybe beeause long-term grazing greatly reduces litter. In sum, although there were o

关键词： Alpine grassland Elevational gradient Soil microbial community Phospholipid fatty acid Plant functional group Soil chemistry Variancepartitioning

Synthesis,Crystal Structure and Analysis of 6-Methoxycarbonylmethyl-7-methyl-6H-dibenzopyran

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Chinese Journal of Structural Chemistry 2015年第9期34卷 1335-1340页

作者：徐迪戴力李兰周智明章军 School of Chemical Engineering and the environment Beijing Institute of Technology

The compound 6-methoxycarbonylmethyl-7-methyl-6H-dibenzopyran has been synthesized by one-pot tandem reaction catalyzed by palladium and norbornene, which was initially structurally characterized by X-ray diffraction. The DSC spectra and chiral HPLC chromatography are reported. Crystal data of the title compound： C17H1603, orthorhombic system, space group Pbca, a = 14.507（3）, b = 9.3993（16）, c = 19.562（3） A, V= 2667.4（8） A3, Mr = 268.30, Dc = 1.336 g/cm3,μ = 0.091 mm-1, Z= 8, F （000） = 1136, R = 0.0653 and wR = 0.1447.

关键词： dibenzopyran palladium catalysis crystal structure chiral center

Landslide Loss and Damage in Sindhupalchok District, Nepal:Comparing Income Groups with Implications for Compensation and Relief

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International Journal of Disaster Risk Science 2018年第2期9卷 157-166页

作者： Kees van der Geest United Nations University institute for environment and Human Security

The 2014 Jure landslide in Sindhupalchok District, Nepal, caused significant loss and damage to ecosystems and livelihoods in the area. In the direct aftermath of the landslide, several disaster loss assessments were conducted, with the aim of counting casualties,injured people, and damaged houses and *** useful and necessary in their own right, such rapid assessments do not reveal the true extent and significance of the losses and damages that people in disaster areas face, including their monetary value. We address this gap, based on a comprehensive household survey(N = 234), as well as other, qualitative research tools. Our results highlight the importance of differentiating between loss and damage in absolute monetary terms as opposed to losses relative to annual income. We find a stark contrast between the high absolute losses incurred by nonpoor households, and the high relative losses—up to 14 times their annual income—experienced by poor *** results have important implications for policy that addresses loss and damage, not only of landslides but also of other disasters. Loss and damage assessments need to take the livelihood characteristics of affected households into account to identify and support those most in need of compensation and relief.

关键词： Compensation and relief Impact assessment Landslides Loss and damage analysis Nepal

Assessing the bird guild patterns in heterogeneous land use types around Jammu,Jammu and Kashmir,India

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Ecological Processes 2020年第1期9卷 564-578页

作者： Asha Sohil Neeraj Sharma institute of Mountain environment University of JammuJammuIndia

Land-use sprawl in the Himalayas has caused the conversion of natural habitat into human-modified habitats,thus degrading ecosystem *** of birds to changing physical environment can be well understood by analyzing their habitat preferences,and foraging dynamics explored to a limited extent in the Himalayan region,as *** achieve a comprehensive understanding of avian guild structure,we used multivariate statistical techniques to classify bird species according to their similarities in foraging patterns and habitat *** based on habitat and diet affinities accounted for rich avian diversity with a total of 208 bird species(about 15%of country’s avifauna)recorded from six different sites during 1 year *** pair-group average cluster analysis performed on the families revealed ten feeding and fifteen habitat guilds among 63 bird families *** forests harbored more species followed by urban forests and agricultural *** and omnivorous outnumbered other feeding guilds in the study *** assemblages were richer in protected areas and semidisturbed landscapes and did not show significant variation between the *** of the study revealed that different functional groups of birds behaved differently,primarily induced by choice of *** site heterogeneity favored avifaunal persistence by providing favorable foraging,roosting,and nesting opportunities to *** of avian guilds indicated level of intactness and ecological integrity of ecosystems *** outcome thus sets the background for long-term analysis of bird-habitat relationship and their foraging *** study has the relevance for decision-makers to integrate avian guild structure as an essential ingredient in formulating conservation strategies.

关键词： Avian guild Food resource utilization Habitat preference Heterogeneous landscape Eutrophic wetland Protected area