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Research on the implementation of the Convention on Biological Diversity among the Shanghai Cooperation Organisation countries
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作者 HAO Yun WU Miao +2 位作者 ZHANG Xiaoyun WANG Lixian HE Jingjing 《Regional Sustainability》 2023年第3期322-331,共10页
The Shanghai Cooperation Organisation(SCO)is the most extensive and populous comprehensive regional cooperation organization in the world,covering about half of the world's population,with not only a huge consumer... The Shanghai Cooperation Organisation(SCO)is the most extensive and populous comprehensive regional cooperation organization in the world,covering about half of the world's population,with not only a huge consumer market,but also rich natural resources and strong productivity.As one of the important platforms for the implementation of the Green Belt and Road Initiative,it is an important opportunity for the SCO to actively participate in global governance and contribute to building a community of global life.To investigate the status of biodiversity conservation in the SCO countries,we used literature analysis approach.We surveyed the performance and international cooperation status of the SCO countries in the implementation of the Convention on Biological Diversity(CBD),listed facing problems and threats to biodiversity conservation,including not optimistic biodiversity conservation project implementation status,contradiction between ecological protection and economic development,impacts of human activities,lack of funds and talents,etc.,and analyzed the biodiversity protection needs of the SCO countries from the perspectives of project and policy implementation status and international cooperation.According to the cooperation between China and the other SCO countries on biodiversity conservation and the post-2020 global biodiversity framework goals,we gave some recommendations:(1)promoting access to genetic resources and benefit-sharing;(2)integrating multiple funds and innovating the implementation of funding mechanism;(3)developing talent training and exchange programs and deepening multilateral cooperation;(4)strengthening cross-border cooperation and improving cooperation network;and(5)establishing a coordination mechanism for biodiversity conservation within the framework of the SCO. 展开更多
关键词 Shanghai Cooperation Organisation(SCO) Biodiversity conservation convention on biological diversity(CBD) International cooperation Cross-border cooperation Multilateral cooperation
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Spinal cord biological safety of image-guided radiation therapy versus conventional radiation therapy 被引量:23
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作者 Wanlong Xu Xilinbaoleri +2 位作者 Hao Liu Ruozheng Wang Jingping Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第35期2755-2760,共6页
Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three m... Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three months after radiation, neuronal injury at the T9-10 levels was observed, including reversible injury induced by spinal image-guided radiation therapy and apoptosis induced by conventional radiation therapy. The number of apoptotic cells and expression of the proapoptotic protein Fas were significantly reduced, but expression of the anti-apoptotic protein heat shock protein 70 was significantly increased after image-guided radiation therapy compared with the conventional method of the same radiation dose. Moreover, the spinal cord cell apoptotic index positively correlated with the ratio of Fas/heat shock protein 70. These findings indicate that 3 months of radiation therapy can induce a late response in the spinal cord to radiation therapy; image-guided radiation therapy is safer and results in less neuronal injury compared with conventional radiation therapy. 展开更多
关键词 Image-guided radiation therapy conventional radiation therapy spinal cord NEURonS apoptosis FAS heat shock protein 70 biological safety vertebral body TUMOR
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Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau,China
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作者 SUN Lin YU Zhouchang +5 位作者 TIAN Xingfang ZHANG Ying SHI Jiayi FU Rong LIANG Yujie ZHANG Wei 《Journal of Arid Land》 SCIE CSCD 2023年第9期1107-1128,共22页
Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during th... Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during the process of succession,the effect of leguminosae on soil physical-chemical and biological properties is still unclear.This study investigated the changes in the composition of plant community,vegetation characteristics,soil physical-chemical properties,and soil biological properties on five former farmlands in China,which had been abandoned for 0,5,10,18,and 30 a.Results showed that,with successional time,plant community developed from annual plants to perennial plants,the importance of Leguminosae and Asteraceae significantly increased and decreased,respectively,and the importance of grass increased and then decreased,having a maximum value after 5 a of abandonment.Plant diversity indices increased with successional time,and vegetation coverage and above-and below-ground biomass increased significantly with successional time after 5 a of abandonment.Compared with farmland,30 a of abandonment significantly increased soil nutrient content,but total and available phosphorus decreased with successional time.Changes in plant community composition and vegetation characteristics not only change soil properties and improve soil physical-chemical properties,but also regulate soil biological activity,thus affecting soil nutrient cycling.Among these,Leguminosae have the greatest influence on soil properties,and their importance values and community composition are significantly correlated with soil properties.Therefore,this research provides more scientific guidance for selecting plant species to stabilize soil ecosystem of farmland to grassland in the Loess Plateau,China. 展开更多
关键词 secondary succession LEGUMINOSAE plant diversity plant community composition soil physical-chemical properties soil biological properties
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Plant biological diversity in natural secondary forests on Mao'er Mountains
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作者 张万里 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第2期75-78,共4页
The forest plant biological diversity investigations were conducted in Laoyeling Forest Ecological Experimental Station on Mao’er Mountains in eastern Heltongjiang Province. Sample plots were six different forest com... The forest plant biological diversity investigations were conducted in Laoyeling Forest Ecological Experimental Station on Mao’er Mountains in eastern Heltongjiang Province. Sample plots were six different forest communities. Field works were divided into three seasons : spring, summer and autumn in one year. The results showed that forest plant biological diversity varied with seasons as well as growth forms. Herb species diversity values were the highest in the community growth forms. Diversity indices No, H’ and E1 were selected out as the best richness, diversity and evenness indices to indicate the biological diversity in forest community. 展开更多
关键词 biological diversity PLANT species FOREST community
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Biological Diversity, Land Degradation and Sustainable Rural Livelihoods
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作者 Michael STOCKING ( Professor of Natural Resource Development,School of Development Studies,University of East Anglia ,Norwich NR4 7TJ, United Kingdom) 《云南植物研究》 CSCD 2000年第S1期4-17,共14页
The 1998 Conference of Parties to the Convention on Biological Diversity asked national governments to demonstrate the importance of biological diversity in supporting rural communities. This paper introduces‘agrodiv... The 1998 Conference of Parties to the Convention on Biological Diversity asked national governments to demonstrate the importance of biological diversity in supporting rural communities. This paper introduces‘agrodiversity’as the primary way in which farmers use biological diversity and, more generally, the natural diversity of the environment for production, including their choice of crops, and management of land, water and biota as a whole. Promoting agrodiversity and understanding how it functions in tropical smallholder farming systems is the best way that importance may be shown. A win-win scenario is presented which links agrodiversity to land degradation control and sustainable rural livelihoods as evidenced by food security. It is argued that policies that encourage biological diversity in areas of land use will not only meet countries’ responsibilities under the Convention but will also address land degradation problems and support to rural livelihoods. The human significance of various types of biological diversity is shown. Sustainable rural livelihoods are presented in the new capital assets framework to demonstrate how rural households may use various components to control land degradation. To enable agrodiversity to be implemented practically, it has been codified into core elements of: biophysical diversity, the diversity of the natural environment that controls the resource base for food production; management diversity that embraces the practices (many of them indigenous) of farmers such as live hedges, soil amendments and ridge tillage techniques; agro-biodiversity which is the diversity of crop, plant and animal combinations; and organisational diversity, the way that farms are owned and operated, and the way that capital assets are allocated. Each element is then systematically related to show how agrodiversity controls land degradation and how it promotes food security. The example of the maize-Mucuna system in South America is cited as an evident demonstration of the value of agrodiversity to both soil conservation and to smallholder farmers’ livelihoods. 展开更多
关键词 biological diversity Agro-biodiversity Agrodiversity Land degradation Livelihoods Food security Rural development SUSTAINABILITY
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Effect of Application of Vermicompost and Conventional Compost Derived from Different Residues on Pea Crop Production and Soil Faunal Diversity in Agricultural System in Garhwal Himalayas India
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作者 Tunira Bhadauria Pradeep Kumar +1 位作者 Rakesh Maikhuri Krishan Gopal Saxena 《Natural Science》 2014年第6期433-446,共14页
Sedentary crop-livestock mixed farming is the predominant agricultural land use in Central Himalaya upland and largely rainfed;agrochemicals are not used at all. Farmers focus on increasing yields with poor soil ferti... Sedentary crop-livestock mixed farming is the predominant agricultural land use in Central Himalaya upland and largely rainfed;agrochemicals are not used at all. Farmers focus on increasing yields with poor soil fertility management practices resulted in sharp decline in production of pea crop in the study site. Therefore in present study options are being looked into devising some conservation strategies that increase yields of pea while reducing harm to soil biodiversity at a local scale here. The present study explores the efficiency of P. excavatus as endemic earthworm species for vermicomposting, the potential utilization of Conventional oak based farmyard manure (FM-O);Conventional pine based farmyard manure(FM-P);Earthworm fed ? Cow dung + oak leaves based vermicompost (VC-O);Earthworm fed ? Cow dung + pine leaves based vermicompost (VC-P);freshly fallen leaf litter (LM) on pea crop productivity and soil faunal diversity in agricultural system, and if the changed soil faunal biodiversity scenario in any way affected the crop production. The higher uptake of nitrogen, higher germination percentage enhanced seedling growth, early emergence flower, increase number of pods, seed, husk , and root biomass was significantly higher in plants which received VC-O followed by VC-P as manure input treatments. The change in the diversity of soil micro arthropods in relation to quality change in organic residues input in experimental plots and expressed as the Simpsons diversity index showed that the diversity of soil fauna is related to improvements in soil conditions resulting from nutrient manipulations through vermicompost and conventional compost treatments. This response of soil biota to increased production most likely represents an increase in the availability of resources through addition of vermicompost when compared to other compost treatments. Alternatively, an increase in predators and therefore predation, could, increase the diversity of its prey, thereby decreasing dominant competitors and reducing the possibility of competitive exclusion, but this needs further studies. Chronosequence study during cropping season indicated that the composition and abundance of soil fauna in agricultural fields changed considerably with time under cultivation. This technology has now been adopted by the farmers in the area once again for growing the pea crop. 展开更多
关键词 HIMALAYAS Crop-Livestock Mixed Farming VERMICOMPOST conventionAL COMPOSTS PEA Crop Production Cropping Pattern Soil Faunal diversity
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Biological Diversity VS. Urgent Protection
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作者 WANGDUI 《China's Tibet》 1998年第6期18-18,共1页
Not long ago, an international symposium was held in Lhasa to discuss ways and means of protecting and managing the region’s biological diversity. Wangdui took the advantage of the occasion to interview Mr. Li Boshen... Not long ago, an international symposium was held in Lhasa to discuss ways and means of protecting and managing the region’s biological diversity. Wangdui took the advantage of the occasion to interview Mr. Li Bosheng, research fellow with the Beijing Plant Research Institute and Director of the Beijing Botanical Garden. Mr. Li is one of the few who discovered the U-turn canyon on the Yarlung Zangbo River. The following is his view on the symposium theme. 展开更多
关键词 biological diversity VS Urgent Protection
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Effects of vegetation type on soil microbial community structure and catabolic diversity assessed by polyphasic methods in North China 被引量:61
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作者 HAN Xue-mei WANG Ren-qing +3 位作者 LIU Jian WANG Meng-cheng ZHOU Juan GUO Wei-hua 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第10期1228-1234,共7页
Soil microbes play a major role in ecological processes and are closely associated with the aboveground plant community. In order to understand the effects of vegetation type on the characteristics of soil microbial c... Soil microbes play a major role in ecological processes and are closely associated with the aboveground plant community. In order to understand the effects of vegetation type on the characteristics of soil microbial communities, the soil microbial communities were assessed by plate counts, phospholipid fatty acid (PLFA) and Biolog microplate techniques in five plant communities, i.e., soybean field (SF), artificial turf (AT), artificial shrub (AS), natural shrub (NS), and maize field (MF) in Jinan, Shandong Province, North China. The results showed that plant diversity had little discernible effect on microbial biomass but a positive impact on the evenness of utilized substrates in Biolog microplate. Legumes could significantly enhance the number of cultural microorganisms, microbial biomass, and community catabolic diversity. Except for SF dominated by legumes, the biomass of fungi and the catabolic diversity of microbial community were higher in less disturbed soil beneath NS than in frequently disturbed soils beneath the other vegetation types. These results confirmed that high number of plant species, legumes, and natural vegetation types tend to support soil microbial communities with higher function. The present study also found a significant correlation between the number of cultured bacteria and catabolic diversity of the bacterial community. Different research methods led to varied results in this study. The combination of several approaches is recommended for accurately describing the characteristics of microbial communities in many respects. 展开更多
关键词 BIOLOG LEGUME microbial biomass plant diversity phospholipid fatty acid (PLFA) soil microbes
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Degradation of chlorpyrifos in laboratory soil and its impact on soil microbial functional diversity 被引量:25
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作者 FANG Hua YU Yunlong +3 位作者 CHU Xiaoqiang WANG Xiuguo YANG Xiaoe YU Jingquan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期380-386,共7页
Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory condition. The degradation half-live of chlorpyrifos at levels o... Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory condition. The degradation half-live of chlorpyrifos at levels of 4, 8, and 12 mg/kg in soil were calculated to be 14.3, 16.7, and 18.0 d, respectively. The Biolog study showed that the average well color development (AWCD) in soils was significantly (P 〈 0.05) inhibited by chlorpyrifos within the first two weeks and thereafter recovered to a similar level as the control. A similar variation in the diversity indices (Simpson index lID and McIntosh index U) was observed, but no significant difference among the values of the Shannon-Wiener index H' was found in chlorpyrifos-treated soils. With an increasing chlorpyrifos concentration, the half-life of chlorpyrifos was significantly (P ≤ 0.05) extended and its inhibitory effect on soil microorganisms was aggravated. It is concluded that chlorpyrifos residues in soil had a temporary or short-term inhibitory effect on soil microbial functional diversity. 展开更多
关键词 BIOLOG CHLORPYRIFOS community-level physiological profile microbial functional diversity
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Species composition,distribution patterns and ecological functions of biological soil crusts in the Gurbantunggut Desert 被引量:12
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作者 Zhang, YuanMing Wu, Nan +1 位作者 Zhang, BingChang Zhang, Jing 《Journal of Arid Land》 SCIE 2010年第3期180-189,共10页
关键词 biological soil crusts species diversity location-specific distribution desert ecosystem
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Effects of cultivation of Osr HSA transgenic rice on functional diversity of microbial communities in the soil rhizosphere 被引量:3
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作者 Xiaobing Zhang Xujing Wang +6 位作者 Qiaoling Tang Ning Li Peilei Liu Yufeng Dong Weimin Pang Jiangtao Yang Zhixing Wang 《The Crop Journal》 SCIE CAS CSCD 2015年第2期163-167,共5页
With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate th... With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate the possible effects of Osr HSA transgenic rice on soil microbial utilization of carbon substrates under field conditions. There were no significant differences in average well-color development(AWCD) values, Shannon–Wiener diversity index(H), Simpson dominance indices(D) and Shannon–Wiener evenness indices(E) of microbial communities in rhizosphere soils at eight samplings between Osr HSA transgenic rice and its non-transgenic counterpart. The main carbon sources utilized by soil microbes were carbohydrates, carboxylic acids, amino acids and polymers. The types,capacities and patterns of carbon source utilization by microbial communities in rhizosphere soils were similar throughout the detection period. We detected no Osr HSA protein in the roots of Osr HSA transgenic rice. We concluded that Osr HSA transgenic rice and the r HSA protein it produced did not alter the functional diversity of microbial communities in the rhizosphere. 展开更多
关键词 BIOLOG method ELISA SOIL microbes Functional diversity
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Trait variation and functional diversity maintenance of understory herbaceous species coexisting along an elevational gradient in Yulong Mountain,Southwest China 被引量:4
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作者 Yahuang Luo Jie Liu +4 位作者 Shaolin Tan Marc W.Cadotte Kun Xu Lianming Gao Dezhu Li 《Plant Diversity》 SCIE CAS CSCD 北大核心 2016年第6期303-311,共9页
Characterizing trait variation across different ecological scales in plant communities has been viewed as a way to gain insights into the mechanisms driving species coexistence.However,little is known about how change... Characterizing trait variation across different ecological scales in plant communities has been viewed as a way to gain insights into the mechanisms driving species coexistence.However,little is known about how changes in intraspecific and interspecific traits across sites influence species richness and community assembly,especially in understory herbaceous communities.Here we partitioned the variance of four functional traits(maximum height,leaf thickness,leaf area and specific leaf area)across four nested biological scales:individual,species,plot,and elevation to quantify the scale-dependent distributions of understory herbaceous trait variance.We also integrated the comparison of the trait variance ratios to null models to investigate the effects of different ecological processes on community assembly and functional diversity along a 1200-m elevational gradient in Yulong Mountain.We found interspecific trait variation was the main trait variation component for leaf traits,although intraspecific trait variation ranged from 10% to 28% of total variation.In particular,maximum height exhibited high plasticity,and intraspecific variation accounted for 44% of the total variation.Despite the fact that species composition varied across elevation and species richness decreased dramatically along the elevational gradient,there was little variance at our largest(elevation)scale in leaf traits and functional diversity remained constant along the elevational gradient,indicating that traits responded to smaller scale influences.External filtering was only observed at high elevations.However,strong internal filtering was detected along the entire elevational gradient in understory herbaceous communities,possibly due to competition.Our results provide evidence that species coexistence in understory herbaceous communities might be structured by differential niche-assembled processes.This approach ee integrating different biological scales of trait variation ee may provide a better understanding of the mechanisms involved in the structure of communities. 展开更多
关键词 biological scale Community assembly Functional diversity Intraspecific variation Species richness Trait variance ratio
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The diversity and potential function of endophytic bacteria isolated from Kobreasia capillifolia at alpine grasslands on the Tibetan Plateau, China 被引量:6
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作者 WANG Ying YANG Cheng-de +3 位作者 YAO Yu-ling WANG Yu-qin ZHANG Zhen-fen XUE Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第9期2153-2162,共10页
A total of 50 endophytic bacterial isolates were obtained from Kobreasia capillifolia at alpine grasslands in the Eastern Qilian Mountains on the Tibetan Plateau in China. Based on the sequencing and phylogenetic anal... A total of 50 endophytic bacterial isolates were obtained from Kobreasia capillifolia at alpine grasslands in the Eastern Qilian Mountains on the Tibetan Plateau in China. Based on the sequencing and phylogenetic analysis of 16 S r DNA genes, all isolates phylogenetically related closely to Bacillus, Acinetobacter, Stenotrophomonas, Brevundimonas, Arthrobacter, Curtobacterium, Paenibacillus, Plantibacter, Promicromonospora, Serratia, and Microbacterium, among which Bacillus was the predominant genus(47.8% of the total number of endophytic isolates). These isolates possessed different biological functions. In 50 endophytic bacteria, 42 isolates produced indole acetic acid(IAA) on King medium. There were seven isolates showing potency of mineral phosphate solubilization in Pikovaskaia's(PKO) liquid medium. Seven isolates exhibited antagonistic effect against Fusarium avenaceum, Colletotrichum coccodes and Phoma foveata. This was the first report on diversity and plant growth promotion of endophytic bacteria from K. capillifolia on alpine grassland in the Eastern Qilian Mountains, Chain. It is essential for revealing the relationship among plant, microorganism, and the special environment because the potential function of endophytic bacteria made a contribution to the interactions of plants and endophytic bacteria. 展开更多
关键词 Tibetan Plateau Kobreasia capillifolia endophytic bacteria diversity biological functions
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Biological characteristics and conservation genetics of the narrowly distributed rare plant Cinnamomum chago(Lauraceae) 被引量:1
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作者 Wenjing Dong Xue Zhang +3 位作者 Yang Guansong Liu Yang Yuehua Wang Shikang Shen 《Plant Diversity》 SCIE CAS CSCD 北大核心 2016年第5期247-252,共6页
Cinnamomum chago(family Lauraceae) is an essential source of timber and oil.This plant is narrowly distributed in the western part of the Yunnan Province.In this study,the distribution,habitat,and biological character... Cinnamomum chago(family Lauraceae) is an essential source of timber and oil.This plant is narrowly distributed in the western part of the Yunnan Province.In this study,the distribution,habitat,and biological characteristics of C.chago were examined through field investigation.The genetic diversity and the variation of the remnant populations were also studied using the inter-simple sequence repeat technique.Results showed that C.chago is mainly distributed in the upstream tributary mountains of Lancang River in Yunlong County of Yunnan Province.The species distribution exhibited a fragmented pattern with five isolated populations and high-frequency anthropogenic interference.A combination of morphological features(opposite leaves,pinnate leaf veins,absence of glandular fossa,large drupe,small punch,and pollen surface with triangular spike grain,with cushion bumps at the base) indicated that C.chago is a key phylogenetic taxon between the two sections of Asian Cinnamomum plants(Sect.Camphora(Trew) Meissn.and Sect.Cinnamomum).Analysis of the genetic diversity of C.chago indicated that it has a moderately high level of genetic diversity at the population and species levels(populations level:N_e = 1.629,H = 0.348,1= 0.504,and PPB = 83.3%;species level:N_e = 1.864,H = 0.460,1 = 0.652,and PPB = 100%).Analysis of molecular variance revealed that 17%of the genetic variation was divided between the populations,whereas 83%was observed within the populations.Based on these results,we suggest the inclusion of C.chago in the Wild Plants with Extremely Small Populations in China.Moreover,the species should be given special attention and protection.Some strategies were proposed for the conservation of the C.chago populations. 展开更多
关键词 Cinnamomum chago HABITAT biological characteristic Genetic diversity Conservation strategies
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Large-scale forest inventories of the United States and China reveal positive effects of biodiversity on productivity 被引量:1
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作者 James V Watson Jingjing Liang +3 位作者 Patrick C Tobin Xiangdong Lei James S Rentch Catherine E Artis 《Forest Ecosystems》 SCIE CSCD 2015年第4期272-287,共16页
Background: With the loss of species worldwide due to anthropogenic factors, especially in forested ecosystems, it has become more urgent than ever to understand the biodiversity-ecosystem functioning relationship (... Background: With the loss of species worldwide due to anthropogenic factors, especially in forested ecosystems, it has become more urgent than ever to understand the biodiversity-ecosystem functioning relationship (BEFR). BEFR research in forested ecosystems is very limited and thus studies that incorporate greater geographic coverage and structural complexity are needed. Methods: We compiled ground-measured data from approx, one half million forest inventory sample plots across the contiguous United States, Alaska, and northeastern China to map tree species richness, forest stocking, and productivity at a continental scale. Based on these data, we investigated the relationship between forest productivity and tree species diversity, using a multiple regression analysis and a non-parametric approach to account for spatial autocorrelation. Results: In general, forests in the eastern United States consisted of more tree species than any other regions in the country. The highest forest stocking values over the entire study area were concentrated in the western United States and Central Appalachia. Overall, 96.4 % of sample plots (477,281) showed a significant positive effect of species richness on site productivity, and only 3.6 % (17,349) had an insignificant or negative effect. Conclusions: The large number of ground-measured plots, as well as the magnitude of geographic scale, rendered overwhelming evidence in support of a positive BEFR. This empirical evidence provides insights to forest management and biological conservation across different types of forested ecosystems. Forest timber productivity may be impaired by the loss of species in forests, and biological conservation, due to its potential benefits on maintaining species richness and productivity, can have profound impacts on the functioning and services of forested ecosystems. 展开更多
关键词 Tree species diversity Forest management biological conservation Continental map of forest diversity Spatial autocorrelation BOOTSTRAP
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Effects of contamination of single and combined cadmium and mercury on the soil microbial community structural diversity and functional diversity 被引量:9
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作者 XIE Xiaomei LIAO Min +1 位作者 MA Aili ZHANG Haijun 《Chinese Journal Of Geochemistry》 EI CAS 2011年第3期366-374,共9页
To assess the effects of single and combined pollution of cadmium (Cd) and mercury (Hg) on soil micro-bial community structural and functional diversities, an incubation experiment was conducted, by employing two soil... To assess the effects of single and combined pollution of cadmium (Cd) and mercury (Hg) on soil micro-bial community structural and functional diversities, an incubation experiment was conducted, by employing two soils, namely, the marine sediment silty loam soil and the yellowish-red soil, in which five levels of Cd, Hg and Cd and Hg in combination were added. After being incubated for 56 days, the phospholipid fatty acids (PLFAs) profile and sole carbon source utilization pattern (BIOLOG) of the samples were tested. The results showed that the compo-sition of the microbial communities changed significantly at different levels of metals application. The principal component analyses (PCA) of PLFAs indicated that the structure of the microbial community was also significantly altered with increasing levels of metals, with increasing PLFAs biomarkers for fungi and actinomycetes, and in-creasing ratio of Gram-positive to Gram-negative bacteria. Sole carbon source utilization pattern analysis revealed that single and combined application of Cd and Hg inhibited significantly the functional activity of soil microorgan-isms, the functional diversity indices [Richness (S), Shannon-Wiener indices (H) and Evenness (EH)] were signifi-cantly lower in polluted soils than those in non-polluted soils, which also significantly altered with increasing levels of metals. PCA for the sole carbon source utilization pattern also indicated that the metal contamination could result in a variable soil microbial community. The results revealed that the combination of Cd and Hg had higher toxicity to soil microbial community structural and functional diversities than the individual application of Cd or Hg. 展开更多
关键词 微生物群落结构 镉(CD) 功能多样性 污染土壤 重金属污染 土壤微生物群落 多样性指数
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Effect of Long-Term Application of Chemical Fertilizers on Microbial Biomass and Functional Diversity of a Black Soil 被引量:22
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作者 KONG Wei-Dong ZHU Yong-Guan +3 位作者 FU Bo-Jie HAN Xiao-Zeng ZHANG Lei HE Ji-Zheng 《Pedosphere》 SCIE CAS CSCD 2008年第6期801-808,共8页
An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to exam... An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA Soil Taxonomy) in Northeast China. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13 to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil. 展开更多
关键词 生物测井 土壤 化学肥料 微生物 生物量
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Effects of Transgenic Bt+CpTI Cotton Cultivation on Functional Diversity of Microbial Communities in Rhizosphere Soils 被引量:1
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作者 Hongmei LIU Xin LAI +2 位作者 Xiaolong SONG Haifang ZHANG Dianlin YANG 《Agricultural Biotechnology》 CAS 2013年第3期60-64,70,共6页
[Objective] This study aimed to investigation the effects of tranagenic Bt + CpTI cotton cultivation on functional diversity of microbial communities in rhizospbere soils. E Method] By using the Biolog method, a comp... [Objective] This study aimed to investigation the effects of tranagenic Bt + CpTI cotton cultivation on functional diversity of microbial communities in rhizospbere soils. E Method] By using the Biolog method, a comparative study was conducted on the utilization level of single carbon source by microbes in the rhi- zosphere soils of transgenic Bt + CpTI cotton sGK321 and its parental conventional cotton ' Shiyuan 321' at different growth stages. [ Result ] The results showed that, compared with the parental conventional cotton, the average well-color development (AWCD) value of micmhial communities in rhizospbere soils of transgenie Bt + CpTI cotton were significantly higher (P 〈 O. 05) at seedling stage and budding stage while significantly lower at flower and boll stage and bell opening stage. Shannon-Wiener diversity index (H) and Simpson dominance index (D) of microbial communities in rhlzesphere soils of transgenic cotton and conventional cotton varied with the different growth stages, whereas the Shannon-Wiener evenness index (E) showed no significant difference between transgenie cotton and convention- al cotton at four growth stages. Principal component analysis indicated that the patterns of carbon source utilization by microbial communities in rhizospbere soils were similar among transgenic cotton at seeding stage and flower and boll stage and parental conventional cotton at seeding stage and budding stage, which were also similar between tranagenic cotton at budding stage and parental conventional cotton at flower and boll stage. [ Conclusion] Analysis of different carbon sources indi- cated that the main carbon sources utilized by soil microbes were carbohydrates, amino acids, carboxylie acids and polymers. 展开更多
关键词 Transgenic Bt CpTI cotton Soil microbe Functional diversity BIOLOG Principal component analysis
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Soil and Water Ecology as the Core Issue of Contemporary Biodiversity Conservation:A Case Study of the Population of Elk,an Endemic Species in China 被引量:1
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作者 Fazheng SUN 《Meteorological and Environmental Research》 CAS 2022年第5期25-27,32,共4页
From a new vision of the theory of soil and water ecology,it is discussed that soil and water ecology is the core issue of contemporary biodiversity protection.First,soil and water ecology constitutes the habitat for ... From a new vision of the theory of soil and water ecology,it is discussed that soil and water ecology is the core issue of contemporary biodiversity protection.First,soil and water ecology constitutes the habitat for biological survival,and is the premise and foundation of biodiversity.Second,soil and water ecology is the material and energy source of biological survival and the prerequisite of biodiversity.Human beings are the beneficiaries and operators of soil and water ecology,which is related to the future and destiny of biodiversity on the earth.It should protect and restore the original,diverse,complete and clean soil and water ecology on the earth from three aspects of protecting pure natural soil and water ecology,protecting and restoring natural soil and water ecology,and building and regenerating artificial soil and water ecology,so as to fundamentally achieve biodiversity protection. 展开更多
关键词 Soil and water ecology biological diversity Protection Core issue
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Soils Typology and Floristic Diversity of the Forest of the“Cite Scientifique”of Brazzaville,Congo 被引量:1
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作者 Jean de Dieu Nzila Victor Kimpouni +3 位作者 Noel Watha-Ndoudy Michele Mercia Nanitelamio Yallo Mouhamed Salisou Diane Prudence Nguila-Ntsoko 《Open Journal of Ecology》 2018年第4期286-304,共19页
A study of the typology of soils and floristic diversity was carried out in the forest of the “Cité Scientifique” of Brazzaville. The study aimed to assess the influence of soil cover on the distribution of tax... A study of the typology of soils and floristic diversity was carried out in the forest of the “Cité Scientifique” of Brazzaville. The study aimed to assess the influence of soil cover on the distribution of taxa. The study covers 18 plots of 625 m2 each, distributed in different soil profiles. The floristic inventory concerns the measurement of diameter of trees with dbh ≥ 10 cm and the counting of herbaceous and shrubs of dbh < 10 cm. The floristic composition reveals a total of 129 plant species distributed in 48 families dominated by Fabaceae and a preponderance of pioneer taxa. The Jaccard coefficients of similarity reveal a low degree of homology of woody plots, whereas for the flora as a whole, the floristic composition is heterogeneous. The Shannon biological diversity index of ligneous varies from 0.6 to 2, against a maximum diversity of 0.69 to 3. The Pielou index of ligneous (0.5 to 0.9) does not reveal any dominance. Soil cover consists of ferrallitic and podzol soils. Their texture is sandy, weakly structured, fragmentary polyhedral throughout the profile, but lumpy and/or nuciform at the surface and sub angular in depth. The porosity decreases proportionally with the depth and thickness of the horizons. The floristic analysis presents an ecosystem with a low degree of diversification for a high floristic richness. The preponderance of anthropization markers is a proof of its very advanced state of disturbance. The study shows that soil cover does not influence the distribution of timber. Indeed, the establishment and development of pioneer species are less prone to soil properties. 展开更多
关键词 ConGO Soil Cover Floristic diversity Urban Forest biological diversity Index Distribution of Taxa
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