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How topography and neighbor shape the fate of trees in subtropical forest restoration:Environmental filtering and resource competition drive natural regeneration
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作者 Haonan Zhang Xingshuo Zhang +7 位作者 Yingying Lv Yanyan Ni Baokun Xu Xiangnan Han Xiao Cao Qingpei Yang Wanggu Xu Zhedong Qian 《Forest Ecosystems》 SCIE CSCD 2024年第1期73-86,共14页
The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering d... The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly understood.To address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total station.We monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year intervals.We fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood scale.Our results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic factors.Furthermore,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees grow,their interaction with these stressors evolves,suggesting a shift in their resource acquisition strategies and response to neighborhood effects and environmental factors.Despite these changes,the relative importance of topographic factors in determining survival and recruitment success remains constant.This research highlights the importance of considering both environmental and neighborhood effects in forest management,particularly in early secondary forest restoration. 展开更多
关键词 Natural regeneration MICROTOPOGRAPHY Neighborhood effects Mortality and recruitment
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Integrated water risk early warning framework of the semi-arid transitional zone based on the water environmental carrying capacity (WECC)
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作者 XIE Yuxi ZENG Weihua QIU Jie 《Journal of Arid Land》 SCIE CSCD 2023年第2期145-163,共19页
Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of rivers.Existing work on the early warning of WECC has mainly... Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of rivers.Existing work on the early warning of WECC has mainly concerned the comprehensive evaluation of the status quo and lacked a quantitative prejudgement and warning of future overload.In addition,existing quantitative methods for short-term early warning have rarely focused on the integrated change trends of the early warning indicators.Given the periodicity of the socioeconomic system,however,the water environmental system also follows a trend of cyclical fluctuations.Thus,it is meaningful to monitor and use this periodicity for the early warning of the WECC.In this study,we first adopted and improved the prosperity index method to develop an integrated water risk early warning framework.We also constructed a forecast model to qualitatively and quantitatively prejudge and warn about the development trends of the water environmental system.We selected the North Canal Basin(an essential connection among the Beijing-Tianjin-Hebei region)in China as a case study and predicted the WECC in 25 water environmental management units of the basin in 2018–2023.We found that the analysis of the prosperity index was helpful in predicting the WECC,to some extent.The result demonstrated that the early warning system provided reliable prediction(root mean square error of 0.0651 and mean absolute error of 0.1418),and the calculation results of the comprehensive early warning index(CEWI)conformed to the actual situation and related research in the river basin.From 2008 to 2023,the WECC of most water environmental management units in the basin had improved but with some spatial differences:the CEWI was generally poor in areas with many human disturbances,while it was relatively good in the upstream regions with higher forest and grass covers as well as in the downstream areas with larger water volume.Finally,through a sensitivity analysis of the indicators,we proposed specific management measures for the sustainability of the water environmental system in the North Canal Basin.Overall,the integrated water risk early warning framework could provide an appropriate method for the water environmental administration department to predict the WECC of the basin in the future.This framework could also assist in implementing corresponding management measures in advance,especially for the performance evaluation and the arrangement of key short-term tasks in the River Chief System in China. 展开更多
关键词 water risk early warning system water environmental carrying capacity prosperity index water management North Canal(Beiyun River)
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A Comparative Analysis of Environmental Quality Assessment Methods for Heavy Metal-Contaminated Soils 被引量:30
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作者 LI Wei-Xin ZHANG Xu-Xiang +5 位作者 WU Bing SUN Shi-Lei CHEN Yan-Song PAN Wen-Yang ZHAO Da-Yong CHENG Shu-Pei 《Pedosphere》 SCIE CAS CSCD 2008年第3期344-352,共9页
Four assessment methods(two pollution indexes and two fuzzy mathematical models) were employed to investigate the environmental quality of four soils around a ferroalloy plant in Nanjing City.Environmental quality was... Four assessment methods(two pollution indexes and two fuzzy mathematical models) were employed to investigate the environmental quality of four soils around a ferroalloy plant in Nanjing City.Environmental quality was assessed as class IV(moderately polluted) for each soil with single-factor index method,and was identified to be classes IV,III(slightly polluted),III,and III for soils A,B,C,and D,respectively,with the comprehensive index model.In comparison with the single-factor index method,the comprehensive index model concerned both dominant parameter and average contribution of all factors to the integrated environmental quality.Using the two fuzzy mathematical methods(single-factor deciding and weighted average models),the environmental risks were determined to be classes IV,III,II(clean),and II for soils A,B,C,and D,respectively.However,divergence of the membership degree to each pollution class still occurred between the two methods.In fuzzy mathematical methods,membership functions were used to describe the limits between different pollution degrees,and different weights were allocated for the factors according to pollution contribution.Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of environmental risk assessment. 展开更多
关键词 环境评估 模糊数学模型 重金属污染 环境保护
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Optical Characteristics of Chromophoric Dissolved Organic Matter(CDOM)in Upstream and Downstream Lakes of Taihu Lake Basin:New Insights for Water Environmental Management
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作者 REN Weixiang WU Xiaodong +4 位作者 CHEN Bingfa CHAO Jianying GE Xuguang YANG Jiuyun YANG Hui 《Chinese Geographical Science》 SCIE CSCD 2022年第4期606-619,共14页
Chromophoric dissolved organic matter(CDOM)is a key component of organic matter that contributes to the ecological functioning of lakes.The lakes in Taihu Lake Basin play an important role in maintaining regional ecol... Chromophoric dissolved organic matter(CDOM)is a key component of organic matter that contributes to the ecological functioning of lakes.The lakes in Taihu Lake Basin play an important role in maintaining regional ecological stabilities;however,the optical characteristics of the CDOM in the upstream and downstream lakes in this basin have not yet been systematically studied.Here,the optical characteristics of CDOM in ten lakes of upstream and downstream of the Taihu Lake Basin were studied using UV-Visible and excitation-emission matrix spectroscopies.Three different fluorophores consisting of two humic-like components(C1,C2)and one protein-like component(C3)were identified by parallel factor analysis.Soil or surface erosion was responsible for the higher abund-ance of C1 in the upstream lakes,and increased biological activities accounted for the higher abundance of C3 in the downstream lakes.Rainfall erosion in the wet season led to an increase in CDOM.We also found that the photodegradation and flocculation degree,which played a significant role in reducing CDOM,were higher in downstream lakes than in upstream lakes.Optical analysis of CDOM provides a promising method for monitoring water qualities(e.g.,total phosphorus and potassium permanganate index)in each lake.Re-ductions in soil or surface erosion in the upstream are needed to improve water quality. 展开更多
关键词 Taihu Lake Basin chromophoric dissolved organic matter(CDOM) excitation-emission spectra parallel factor analysis(PARAFAC)
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Spatial distributions of intra-community tree species under topographically variable conditions
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作者 LV Ting ZHAO Rong +5 位作者 WANG Ning-jie XIE Lei FENG Yue-yao LI Yao DING Hui FANG Yan-ming 《Journal of Mountain Science》 SCIE CSCD 2023年第2期391-402,共12页
Growing public awareness of the importance of protecting biodiversity requires the development of forest practices that increase the complexity of stand structure.Understanding the ecological processes of different fo... Growing public awareness of the importance of protecting biodiversity requires the development of forest practices that increase the complexity of stand structure.Understanding the ecological processes of different forest vegetation provide insights into community coexistence mechanisms.In this paper,the spatial patterns of three different communities,evergreen broadleaf forest,deciduous broadleaf forest,and mixed needleleaf and broadleaf forest at Mt.Huangshan,China,were quantified with four structural parameters,the mingling index,the uniform angle index,the diameter dominance index and the crowdedness index.All trees with a diameter at breast height of more than 5 cm were measured.Our analyses highlighted that most trees in the three communities were extremely dense and slightly clumped,with a moderate size differentiation and high mixed structure.In mixed needleleaf and broadleaf forest,the distribution pattern of tree species was better than the other two forests.Overall,spatial patterns in mixed needleleaf and broadleaf forest exhibited a strong stability-effect,that is,the stand had a suitable environment for the stable survival of the forest.With the increasing of elevation,the degree of the mingling index and the crowdedness index increased,however,there was no influence on the uniform angle index and the diameter dominance index.Further,at the same elevation,four structural parameters of shady slope were larger than that of sunny slope.Then we found the relationship between stand spatial structure and environment factors had important influence on forest structure.Our work contributes to the knowledge of population structure,and further provide theoretical basis for the sustainable development of forest resources and protecting biodiversity of Huangshan Mountain.In future studies,it is necessary to explore the limiting factors of community spatial distribution by combining species diversity and functional traits. 展开更多
关键词 Intra-community Stand spatial structure Comprehensive evaluation Topographical factor Forest vegetation
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Phosphorylation of SiRAV1 at Ser31 regulates the SiCAT expression to enhance salt tolerance in Setaria italica
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作者 LI Qiao-lu LI Zhi-yong +2 位作者 WANG Meng-meng YAN Jing-wei FANG Lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3638-3651,共14页
Salinity severely affects plant growth and development.Thus,it is crucial to identify the genes functioning in salt stress response and unravel the mechanism by which plants against salt stress.This study used the pho... Salinity severely affects plant growth and development.Thus,it is crucial to identify the genes functioning in salt stress response and unravel the mechanism by which plants against salt stress.This study used the phosphoproteomic assay and found that 123 of the 4000 quantitative analyzed phosphopeptides were induced by salt stress.The functional annotation of the non-redundant protein database(NR)showed 23 differentially expressed transcription factors,including a phosphopeptide covering the Serine 31 in the RAV(related to ABI3/VP1)transcription factor(named SiRAV1).SiRAV1 was located in the nucleus.Phenotypic and physiological analysis showed that overexpressing SiRAV1 in foxtail millet enhanced salt tolerance and alleviated the salt-induced increases of H_(2)O_(2) accumulation,malondialdehyde(MDA)content,and percent of electrolyte leakage.Further analysis showed that SiRAV1 positively regulated SiCAT expression to modulate the catalase(CAT)activity by directly binding to the SiCAT promoter in vivo and in vitro.Moreover,we found that phosphorylation of SiRAV1 at the Ser31 site positively regulated salt tolerance in foxtail millet via enhancing its binding ability to SiCAT promoter but did not affect its subcellular localization.Overall,our results define a mechanism for SiRAV1 function in salt response where salt-triggered phosphorylation of SiRAV1 at Ser31 enhances its binding ability to SiCAT promoter,and the increased SiCAT expression contributes to salt tolerance in foxtail millet. 展开更多
关键词 foxtail millet salt stress phosphoproteomic SiRAV1 SiCAT
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Anthropogenic footprints are invading global habitats of Indo-Pacific humpback dolphins
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作者 Yongquan Lu Guilin Liu +3 位作者 William W.L.Cheung Yuyang Xian Weijia Chen Dandan Yu 《Geography and Sustainability》 CSCD 2023年第1期58-69,共12页
As ecologically fragile areas,coastal zones are affected by both anthropogenic activities and climate change.However,the impacts of these factors on large nearshore mammals,such as Indo-Pacific humpback dolphins(IPHDs... As ecologically fragile areas,coastal zones are affected by both anthropogenic activities and climate change.However,the impacts of these factors on large nearshore mammals,such as Indo-Pacific humpback dolphins(IPHDs,Sousa chinensis),are poorly understood.Here,modeling revealed that the suitable habitats of IPHDs are affected mainly by the sea surface temperature(SST),and the habitat suitability decreases as the distance to the nearest coastline increases.In addition,anthropogenic activities involving demersal fishing,contamination and shipping have narrowed IPHD habitats and reduced the habitat suitability.We found that climate change will further narrow suitable habitats located farther than 7 km from coastlines and trigger habitat losses in the eastern Taiwan Strait by 2090-2100 under the Representative Concentration Pathway(RCP)8.5 scenario.The projected decreases in habitat suitability and area emphasize the urgency of establishing connected marine protected areas(MPAs)while considering climate change,intergovernmental cooperation,and public involvement. 展开更多
关键词 Anthropogenic activities Climate change Indo-Pacific humpback dolphins Habitat shifts MaxEnt modeling
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Fecal DNA metabarcoding reveals the dietary composition of wintering Red-crowned Cranes(Grus japonensis)
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作者 Hongyi Liu Wei Xu +6 位作者 Nan Xu Wenwen Zhang Haoming Jiang Yongqiang Zhao Changhu Lu Ying Zhu Peng Xu 《Avian Research》 SCIE CSCD 2023年第4期647-655,共9页
Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management measures.The Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast Asia.Previou... Understanding the diet of threatened wildlife is vital for species-specific conservation and habitat management measures.The Red-crowned Crane(Grus japonensis)is a vulnerable bird distributed in Northeast Asia.Previous dietary studies of this bird focused mainly on its plant food composition based on field observations and microhistological identification.Herein,a total of 45 fecal samples were collected in November,December and January(15 fecal samples each month)from wintering cranes,and then subjected to a high throughput sequencing meta-barcoding approach to determine the primary plant(rbcL)and animal(COI)food items in their diet.A total of 230 operational taxonomic units(OTUs)of plant foods and 371 OTUs of animal foods were obtained.The main plant foods in the wintering period were Miscanthus,Zea,and Hordeum genera,which were similar to those in the breeding and the migration periods.Both agricultural and natural plants were detected,indicating a relatively broad dietary niche for this crane species.However,the main animal foods were representatives of Theridiidae,Megascolecidae,and Agelenidae,in sharp contrast to previous studies.The higher number of small terrestrial arthropods in animal foods might be due to the indirect intake of plants.The composition of both plant and animal foods in the diet showed the highest diversity in December,while it was homogeneous in January.The plant of Zea genus became the main source of nutrition in late winter,as supplementary feeding was performed in the reserve,which could help Red-crowned Cranes to get through the cold season.The results obtained in this work would contribute to the development of effective conservation strategies for the Red-crowned Crane. 展开更多
关键词 Dietary composition Dietary niche Metabarcoding Molecular diet analysis Red-crowned Crane
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Effects of hydrodynamics processes on phosphorus fluxes from sediment in large,shallow Taihu Lake 被引量:23
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作者 YOU Ben-sheng ZHONG Ji-cheng +3 位作者 FAN Cheng-xin WANG Tong-cheng ZHANG Lu DING Shi-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1055-1060,共6页
在湖沉积,超营养作用的一个主要原因和水质的随后的恶化的磷(P) 的周转,需要深理解。在这研究, P 版本上的暂停的效果与 Y 形状仪器在圆柱的缩影被学习。结果显示在越过沉积水接口(Fss ) 和风速度的推迟的物质的流动之间有一道正相... 在湖沉积,超营养作用的一个主要原因和水质的随后的恶化的磷(P) 的周转,需要深理解。在这研究, P 版本上的暂停的效果与 Y 形状仪器在圆柱的缩影被学习。结果显示在越过沉积水接口(Fss ) 和风速度的推迟的物质的流动之间有一道正相关,并且增加的 FSS 在各个期间弯屈由一个稳定的状态跟随的过程。在轻、中等、大的风条件下面的最大的 FSS 是 299.9 ± 4 1.1, 573.4 ± 6 1.7,和 2093.8 ± 2 15.7 g/m2 分别地。然而,越过沉积水接口(FP ) 的 P 的流动没作为反应弯屈紧张的 Fss 跟随一个类似的模式,它增加了并且到达最大值在起始为光的 120 min 弯屈,然后逐渐地减少了,与 9.4 ± 1 .9 mg/m2 的最大的流动。在开始的 30 min 的 FP 的快速的增加在中等的风下面被观察,与 11.2 ± 0 .6 mg/m2 的最大的流动。令人惊讶地,大风与 3.5 ± 0 .9 mg/m2 的最大的流动比在轻、中等的风条件下面引起了更少的 FP。在水列的 Fss 在风以后在沉积过程期间显然衰退了,但是 FP 与风政体变化了。没有明显的差别在 8 h 沉积过程以后在 FP 上被检测,与起始的值相比,它意味着小冗余的 P 在风以后在水列离开了。 展开更多
关键词 太湖 水处理 悬浮物 沉降
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A New Species of the Genus Xenophrys(Amphibia: Anura: Megophryidae) from Libo County, Guizhou, China 被引量:9
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作者 Yanan ZHANG Gang LI +5 位作者 Ning XIAO Jiaqi LI Tao PAN Hui WANG Baowei ZHANG Jiang ZHOU 《Asian Herpetological Research》 SCIE CSCD 2017年第2期75-85,共11页
A new species of the genus Xenophrys is described from a karst cave environment of Libo County, Guizhou Province, Southern China. The new species, Xenophrys liboensis sp. nov., is distinguished from its congeners by a... A new species of the genus Xenophrys is described from a karst cave environment of Libo County, Guizhou Province, Southern China. The new species, Xenophrys liboensis sp. nov., is distinguished from its congeners by a combination of the following characters: 1) tympanum distinct; 2) vomerine teeth present; 3) the length of lower arm and hand larger than the half of snout-vent; 4) heels overlapped slightly when the flexed legs are held at right angles to the body axis; 5) toe tips with rudimentary webs and without grooves; 6) dermal fringes moderate; 7) tubercles on the dorsum forming an X-shaped weak ridge; 8) horn-like tubercle at the edge of the upper eyelid distinct; 9) color of the iris in life is brown. In Bayesian phylogenetic analysis of 22 species of Xenophrys, all the individuals of X. liboensis sp. nov. clustered into a monophyletic clade with high posterior probabilities. In addition, the ranges of genetic divergences of X. liboensis sp. nov. with other species were interspecific rather than intraspecific. Based on the above evidences, we consider that X. liboensis sp. nov. is a valid species in Xenophrys. 展开更多
关键词 荔波县 新属种 贵州省 角蟾科 两栖纲 中国 系统发育分析 洞穴环境
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Effect of exposure to ambient PM2.5 pollution on the risk of respiratory tract diseases: a meta-analysis of cohort studies 被引量:16
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作者 Qian Liu Cheng Xu +5 位作者 Guixiang Ji Hui Liu Wentao Shao Chunlan Zhang Aihua Gu Peng Zhao 《The Journal of Biomedical Research》 CAS CSCD 2017年第2期130-142,共13页
The International Agency for Research on Cancer and the World Health Organization have designated airborne particulates,including particulates of median aerodynamic diameter < 2.5um(PM_(2.5)),as Group 1 carcinogens... The International Agency for Research on Cancer and the World Health Organization have designated airborne particulates,including particulates of median aerodynamic diameter < 2.5um(PM_(2.5)),as Group 1 carcinogens.It has not been determined,however,whether exposure to ambient PM_(2.5) is associated with an increase in respiratory related diseases.This meta-analysis assessed the association between exposure to ambient fine particulate matter(PM_(2.5)) and the risk of respiratory tract diseases,using relevant articles extracted from PubMed,Web of Science,and Embase.In results,of the 1,126 articles originally identified,35(3.1%) were included in this meta-analysis.PM_(2.5)was found to be associated with respiratory tract diseases.After subdivision by age group,respiratory tract disease,and continent,PM_(2.5) was strongly associated with respiratory tract diseases in children,in persons with cough,lower respiratory illness,and wheezing,and in individuals from North America,Europe,and Asia.The risk of respiratory tract diseases was greater for exposure to traffic-related than non-traffic-related air pollution.In children,the pooled relative risk(RR) represented significant increases in wheezing(8.2%),cough(7.5%),and lower respiratory illness(15.3%).The pooled RRs in children were 1.091(95%CI:1.049,1.135) for exposure to<25 μg/m^3 PM_(2.5),and 1.126(95%CI:1.067,1.190) for exposure to > 25 μg/m^3 PM_(2.5).In conclusion,exposure to ambient PM_(2.5) was significantly associated with the development of respiratory tract diseases,especially in children exposed to high concentrations of PM_(2.5). 展开更多
关键词 PM2.5 呼吸道疾病 队列研究 风险 环境 大气细颗粒物 空气动力学 世界卫生组织
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A New Species of the Genus Tylototriton(Amphibia: Urodela: Salamandridae) from the Southern Dabie Mountains in Anhui Province 被引量:6
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作者 Lifu QIAN Xiaonan SUN +7 位作者 Jiaqi LI Weibo GUO Tao PAN Xing KANG Hui WANG Jianping JIANG Jun WU Baowei ZHANG 《Asian Herpetological Research》 SCIE CSCD 2017年第3期151-164,共14页
A new species of the genus Tylototriton is described,from Yuexi county,Anhui province,in the south of the Dabie Mountains.It is based on morphological and molecular analysis.The new species is identified as belonging ... A new species of the genus Tylototriton is described,from Yuexi county,Anhui province,in the south of the Dabie Mountains.It is based on morphological and molecular analysis.The new species is identified as belonging to the Tylototriton asperrimus group and shares a number of similarities with T.wenxianensis,T.broadoridgus and T.dabienicus.The diagnostic characteristics of the new species are as follows: the head length is greater than the width of the head; bony ridges on the head are prominent and necked-in; the distal digit ends,ventral digits,peripheral area of the cloaca and the tail's lower edge are orange.The result from the molecular analysis of the genus Tylototriton(including the type specimen of the new species) based on three mitochondrial genes(ND1,ND2 and CYTB) indicated that the new species was close to T.wenxianensis,T.dabienicus,and T.broadoridgus,but formed an independent clade.This result was consistent with the morphological analysis above,which supports the theory that the population distributed in the south of the Dabie Mountains,namely in from Yuexi county,Anhui province,represented a distinct species,Tylototriton anhuiensis sp.nov. 展开更多
关键词 细痣疣螈 大别山 安徽省 蝾螈科 有尾目 两栖纲 分子分析 新物种
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Impacts of Drought and Human Activity on Vegetation Growth in the Grain for Green Program Region,China 被引量:6
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作者 WANG Hao LIU Guohua +3 位作者 LI Zongshan YE Xin FU Bojie LV Yihe 《Chinese Geographical Science》 SCIE CSCD 2018年第3期470-481,共12页
The Chinese government adopted six ecological restoration programs to improve its natural environments. Although these programs have proven successful in improving local environments, some studies have questioned thei... The Chinese government adopted six ecological restoration programs to improve its natural environments. Although these programs have proven successful in improving local environments, some studies have questioned their performance when regions suffer from drought. Whether we should consider the effects of drought on vegetation change in assessments of the benefits of ecological restoration programs is unclear. Therefore, taking the Grain for Green Program(GGP) region as a study area, we estimated vegetation growth in the region from 2000–2010 to clarify the trends in vegetation and their driving forces. Results showed that: 1) vegetation growth increased in the GGP region during 2000–2010, with 59.4% of the area showing an increase in the Normalized Difference Vegetation Index(NDVI). This confirmed the benefits of the ecological restoration program. 2) Drought can affect the vegetation change trend, but human activity plays a significant role in altering vegetation growth, and the slight downward trend in the NDVI was not consistent with the severity of the drought. Positive human activity led to increased NDVI in 89.13% of areas. Of these, 22.52% suffered drought, but positive human activity offset the damage in part. 3) Results of this research suggest that appropriate human activity can maximize the benefits of ecological restoration programs and minimize the effects of extreme weather. We therefore recommend incorporating eco-risk assessment and scientific management mechanisms in the design and management of ecosystem restoration programs. 展开更多
关键词 植被生长 中国政府 干旱 程序 谷物 格林 生态系统恢复 科学管理机制
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Resurrection of the Genus Leptomantis, with Description of a New Genus to the Family Rhacophoridae(Amphibia:Anura) 被引量:8
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作者 Dechun JIANG Ke JIANG +2 位作者 Jinlong REN Jun WU Jiatang LI 《Asian Herpetological Research》 SCIE CSCD 2019年第1期1-12,共12页
Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and co... Genus Rhacophorus Kuhl and Van Hasselt, 1 822 is one of the most diverse genera of the family Rhacophoridae, and its taxonomy of genus Rhacophorus faces major challenges because of rapidly described new species and complex interspecies relations. In this study, we investigate the generic taxonomy within the genus Rhacophorus based on 1 972 bp of mitochondrial genes(12S rRNA, tRNA-val and 16S rRNA), containing 102 sequences from 58 species. The results reveal three well-supported and highly diverged matrilines that correspond with morphological characteristics and geographic distribution. Accordingly, we consider these three lineages as distinct genera: Rhacophorus sensu stricto, resurrected genus Leptomantis Peters, 1867, and the genus Zhangixalus gen. nov. 展开更多
关键词 Rhacophorus TAXONOMIC revision tree FROG Zhangixalus gen.nov.
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Effects of freezing intensity on soil solution nitrogen and microbial biomass nitrogen in an alpine grassland ecosystem on the Tibetan Plateau,China 被引量:5
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作者 YANG Zhaoping GAO Jixi +1 位作者 YANG Meng SUN Zhizhong 《Journal of Arid Land》 SCIE CSCD 2016年第5期749-759,共11页
The change of freeze-thaw pattern of the Tibetan Plateau under climate warming is bound to have a profound impact on the soil process of alpine grassland ecosystem;however,the research on the impact of the freeze-thaw... The change of freeze-thaw pattern of the Tibetan Plateau under climate warming is bound to have a profound impact on the soil process of alpine grassland ecosystem;however,the research on the impact of the freeze-thaw action on nitrogen processes of the alpine grassland ecosystem on the Tibetan Plateau has not yet attracted much attention.In this study,the impact of the freezing strength on the soil nitrogen components of alpine grassland on the Tibetan Plateau was studied through laboratory freeze-thaw simulation experiments.The 0–10 cm topsoil was collected from the alpine marsh meadow and alpine meadow in the permafrost region of Beilu River.In the experiment,the soil samples were cultivated at –10°C,–7°C,–5°C,–3°C and –1°C,respectively for three days and then thawed at 2°C for one day.The results showed that after the freeze-thaw process,the soil microbial biomass nitrogen significantly decreased while the dissolved organic nitrogen and inorganic nitrogen significantly increased.When the freezing temperature was below –7°C,there was no significant difference between the content of nitrogen components,which implied a change of each nitrogen component might have a response threshold toward the freezing temperature.As the freeze-thaw process can lead to the risk of nitrogen loss in the alpine grassland ecosystem,more attention should be paid to the response of the soil nitrogen cycle of alpine grasslands on the Tibetan Plateau to the freeze-thaw process. 展开更多
关键词 微生物生物量氮 草地生态系统 高寒草甸 西藏高原 草地土壤 冻结强度 固溶态 土壤微生物量氮
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Characteristics of microfauna and their relationships with the performance of an activated sludge plant in China 被引量:5
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作者 ZHOU Kexin XU Muqi +1 位作者 LIU Biao CAO Hong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期482-486,共5页
微动物志组织的出现和许多与在中国的 Baoding Lugang 污水处理工厂的物理化学、运作的参数相比。属于并且爬行纤毛虫类是纤毛虫类的主导的组。爬行纤毛虫类和留有遗嘱的阿米巴与自河 BOD5 (生物化学的氧需求) 显示出一个强壮的协会。... 微动物志组织的出现和许多与在中国的 Baoding Lugang 污水处理工厂的物理化学、运作的参数相比。属于并且爬行纤毛虫类是纤毛虫类的主导的组。爬行纤毛虫类和留有遗嘱的阿米巴与自河 BOD5 (生物化学的氧需求) 显示出一个强壮的协会。因此,自从他们的数字减少了,当这个过程生产了差的优秀自河,这二个组是可能的是有用简历指示物。留有遗嘱的阿米巴也有重要负相关与自河 TN (总氮) , NH4+-N, SS (推迟的固体) 和 SVI (污泥容量的索引) ,它意味着这组纤毛虫类可以是活性污泥系统的好性能的指示物。食肉的纤毛虫类和 flagellates 与 SVI 有重要正相关,建议这二个组可以是污泥的坏解决条件的指示物。因为微动物志种类的鉴定困难、费时间,我们用微动物志建议功能的组评估活性污泥系统的性能。 展开更多
关键词 活性炭 微生物系统 生命 环境保护
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Trade-offs and Synergies of Ecosystem Services in the Taihu Lake Ba- sin of China 被引量:5
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作者 QIAO Xuning GU Yangyang +3 位作者 ZOU Changxin WANG Lei LUO Juhua HUANG Xianfeng 《Chinese Geographical Science》 SCIE CSCD 2018年第1期86-99,共14页
Understanding the spatial interactions among multiple ecosystem services is crucial for ecosystem services management. Ecosystem services, including crop production, freshwater supply, aquatic production, net primary ... Understanding the spatial interactions among multiple ecosystem services is crucial for ecosystem services management. Ecosystem services, including crop production, freshwater supply, aquatic production, net primary production, soil conservation, water conservation, flood regulation, forest recreation, were measured at 1-km grid scale covering the Taihu Lake Basin(TLB) of China. Our objective is to get a comprehensive understanding of the spatial distributions, trade-offs, synergies of multiple ecosystem services across the TLB. Our results found that: 1) majority of ecosystem services were clustered in space and had a similar spatial distribution pattern with the geographical resource endowment. Most of the landscape contributed a high supply of no services, one or two, and a low supply of three to seven services. 2) There were high correlation between forest recreation and freshwater supply and regulating services. Aquatic production had low correlation with other services. 3) The changes of provisioning services led to trade-offs between regulating services and cultural services in the TLB, while synergies mainly occurred among the provisioning service. 4) The spatial relationships of multiple services are consistent at 1-km spatial scale, counties and provinces. This research could help integrate multiple ecosystem services across scales and serve as a reference for decision making. 展开更多
关键词 生态系统服务 协同作用 交易 中国 空间相互作用 淡水供应 服务管理 防洪条例
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A New Species of the Genus Rhacophorus (Anura: Rhacophoridae) from Dabie Mountains in East China 被引量:5
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作者 Tao PAN Yanan ZHANG +9 位作者 Hui WANG Jun WU Xing KANG Lifu QIAN Kai LI Yu ZHANG Jinyun CHEN Dingqi RAO Jianping JIANG Baowei ZHANG 《Asian Herpetological Research》 SCIE CSCD 2017年第1期1-13,共13页
A new species of rhacophorid of the genus Rhacophorus is described from the Dabie Mountains of west Anhui,east China.The new species,Rhacophorus zhoukaiyae sp.nov.is distinguished from its congeners by a combination o... A new species of rhacophorid of the genus Rhacophorus is described from the Dabie Mountains of west Anhui,east China.The new species,Rhacophorus zhoukaiyae sp.nov.is distinguished from its congeners by a combination of the following characters: 1) the ventral surface and front-and-rear of the femur is paler yellowish and decorated with irregular grayish blotching,and without obvious spots on the dorsum of the hand and foot webbing; 2) the outer metatarsal tubercle is small; 3) outer fingers are half-webbed and outer toes two third webbed; 4) the skin on the dorsum is smooth and without compressed warts; 5) the throat,chest and belly are pure paler yellowish; 6) the dorsal part of the fingers and toes are grayish-white; 7) the iris is golden-yellow.In addition,the phylogenetic tree showed that all the individuals of R.zhoukaiyae sp.nov.clustered into one distinct clade which suggested the validity of this species.This results could also be used to the support of species delimitation.Currently,this species is known only from mid-elevation montane evergreen forest in the Dabie Mountains of west Anhui,China. 展开更多
关键词 大别山 树蛙科 华东地区 蛙属 系统进化树 常绿阔叶林 金黄色 物种
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A New Species of the Asi an Toad Genus Megophrys sensu lato (Anura: Megophryidae) from Guizhou Province, China 被引量:4
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作者 Jing LIU Shize LI +4 位作者 Gang WEI Ning XU Yanlin CHENG Bin WANG Jun WU 《Asian Herpetological Research》 SCIE CSCD 2020年第1期1-18,共18页
We describe a new species of the genus Megophr ys from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an indepen... We describe a new species of the genus Megophr ys from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent clade nested into the Megophrys clade and sister to M. minor. On morphology,the new species is distinguished from its congeners by a combination of the following characters:(1) small body size with SVL < 39.2 mm in male and SVL < 40.4 mm in female;(2) vomerine teeth absent;(3) tongue not notched behind;(4) a small horn-like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two or three metacarpal tubercles in hand;(7) relative finger lengths: Ⅰ< Ⅱ< Ⅴ< Ⅲ;(8) toes without webbing;(9) heels overlapped when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers. 展开更多
关键词 Taxonomy new species molecular PHYLOGENETIC analysis morphology China
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An ethnobotanical study of forage plants in Zhuxi County in the Qinba mountainous area of central China 被引量:3
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作者 Jun Yang Jifeng Luo +5 位作者 Qiliang Gan Leiyu Ke Fengming Zhang Hairu Guo Fuwei Zhao Yuehu Wang 《Plant Diversity》 SCIE CAS CSCD 2021年第3期239-247,共9页
In the Qinba mountainous area of Central China,pig farming has a significant impact on the growth of the rural economy and has substantially increased farmer incomes.Traditional knowledge plays an important role in th... In the Qinba mountainous area of Central China,pig farming has a significant impact on the growth of the rural economy and has substantially increased farmer incomes.Traditional knowledge plays an important role in the selection of forage plant species for pig farming by local people.This study aimed to identify the forage plants used for pig feeding and to catalog indigenous knowledge regarding their use.During 2016 and 2017,ethnobotanical surveys and inventories were conducted in Zhuxi County,Hubei Province,China.Data were collected using semi-structured interviews,key informant reports,free listings,guided field walks,and participatory observations with 77 households in 16 villages in 13 towns/townships.The obtained data were analyzed using a relative frequency citation(RFC)index.Overall,145 wild forage plants from 91 genera and 31 families were recorded.The most cited families were Asteraceae,Polygonaceae,Urticaceae,Amaranthaceae,Fabaceae,Cruciferae,Caryophyllaceae,and Lamiaceae.Whole plants(75.9%)and tender leaves(12.4%)were the most frequently used parts of the plants.Most of the forage plants were herbaceous(88.9%).Almost all forage plants could be collected throughout the year(62.7%).Raw and cooked were the two main preparation methods.The most frequently cited species were Taraxacum mongolicum,Bidens pilosa,Sonchus oleraceus,Pilea verrucosa,and Pilea pumila var.obtusifolia.A total of 14 species were identified as the top forage plants in Zhuxi County based on their RFC values(RFC value greater than 0.5).Local people possess rich traditional knowledge about the utilization and management of forage plants for pig feeding.However,the maintenance of this traditional knowledge may be seriously threatened by changes in pig feeding modes and the lack of successors.Appropriate strategies and action plans have been suggested for the conservation of traditional knowledge associated with biodiversity and the sustainable use of forage species resources.These include 1)taking targeted measures to protect forage resources and associated traditional knowledge;2)strengthening research on the forage plants with the highest RFC values for nutritional value,digestibility,other functions,and ecological status;and 3)enhancing the identification of poisonous forage plants. 展开更多
关键词 Qinba mountainous area Zhuxi county ETHNOBOTANY Traditional knowledge Pig forage plants
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