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Purification Effects of Aquatic Vegetations on Lake Wetland Water Environment and Analysis of the Influencing Factors in Hongze Lake 被引量:3
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作者 赵洪波 吴睿 卡林 《Agricultural Science & Technology》 CAS 2012年第1期211-216,共6页
[Objective] To study the purification effect of plant community on wetland water environment in Hongze Lake, and to provide references to the ecological restoration of this area. [Methed] The typical lakeside zone of ... [Objective] To study the purification effect of plant community on wetland water environment in Hongze Lake, and to provide references to the ecological restoration of this area. [Methed] The typical lakeside zone of Hongze Lake Wetland National Nature Reserve was taken as the study area. Through the field survey based on environmental characteristics of aquatic areas and non-aquatic areas, combined with laboratory test, the content changes of nutrients (N and P), COD (chemical oxygen demand) and SD (transparency) levels in the water body of lake wetland were measured; the purification effect of the lake wetland ecosystem in the growth process of aquatic vegetation was quantitatively analyzed, and possible influ- encing factors were discussed. [Result] Aquatic vegetation could remove the TN, TP, COD, Chla in wetland water environment and had obvious effects on the changes of SD content. Competition between aquatic plants can inhibit the growth of algae and relieve the eutrophication of water body. [Conclusion] This study provided theoretical basis for ecological restoration and enhancement of self-purification capability in the lakeside zone of Hongze Lake. 展开更多
关键词 Aquatic vegetation Water environment Purification effect Influencing factors
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Impact of Tourism Interference on Vegetations in Xijing Mountain
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作者 杨少华 侯平 《Journal of Landscape Research》 2010年第12期32-36,40,共6页
[Objective] Taking Xijing Mountain for example,this study investigates characteristics of roadside plant communities and width changes of trampled vegetations by the tourist road,analyzes influence of tourism activiti... [Objective] Taking Xijing Mountain for example,this study investigates characteristics of roadside plant communities and width changes of trampled vegetations by the tourist road,analyzes influence of tourism activities on environment.[Method] Characteristics of roadside plant communities are studied by applying species diversity index,coverage and other such indexes;from the bottom to the top of Xijing Mountain,investigation objects are selected along the tourist road to measure the trampled width of vegetations.[Result] Characteristics of plant communities,trampled vegetations are both closely related to the design of tourist road.[Conclusion] Suggestions are proposed for the design of tourist road. 展开更多
关键词 Plant community characteristics WIDTH of trampled vegetations Design of TOURIST ROAD
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Echocardiographic predictors and associated outcomes of multiple vegetations in infective endocarditis:A pilot study
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作者 Ajay Kumar Mishra Kannu Bansal +6 位作者 Ibragim Al-Seykal Pradnya B Bhattad Anu Anna George Anil Jha Nitish Sharma Jennifer Sargent Mark J Kranis 《World Journal of Cardiology》 2024年第6期318-328,共11页
BACKGROUND Infective endocarditis(IE)is a life-threatening infection with an annual mortality of 40%.Embolic events reported in up to 80%of patients.Vegetations of>10 mm size are associated with increased embolic e... BACKGROUND Infective endocarditis(IE)is a life-threatening infection with an annual mortality of 40%.Embolic events reported in up to 80%of patients.Vegetations of>10 mm size are associated with increased embolic events and poor prognosis.There is a paucity of literature on the association of multiple vegetations with outcome.AIM To study the echocardiographic(ECHO)features and outcomes associated with the presence of multiple vegetations.METHODS In this retrospective,single-center,cohort study patients diagnosed with IE were recruited from June 2017 to June 2019.A total of 84 patients were diagnosed to have IE,of whom 67 with vegetation were identified.Baseline demographic,clinical,laboratory,and ECHO parameters were reviewed.Outcomes that were studied included recurrent admission,embolic phenomenon,and mortality.RESULTS Twenty-three(34%)patients were noted to have multiple vegetations,13(56.5%)were male and 10(43.5%)were female.The mean age of these patients was 50.Eight(35%)had a prior episode of IE.ECHO features of moderate to severe valvular regurgitation[odds ratio(OR)=4],presence of pacemaker lead(OR=4.8),impaired left ventricle(LV)relaxation(OR=4),and elevated pulmonary artery systolic pressure(PASP)(OR=2.2)are associated with higher odds of multiple vegetations.Of these moderate to severe valvular regurgitation(P=0.028),pacemaker lead(P=0.039)and impaired relaxation(P=0.028)were statistically significant.These patients were noted to have an increased association of recurrent admissions(OR=3.6),recurrent bacteremia(OR=2.4),embolic phenomenon(OR=2.5),intensive care unit stay(OR=2.8),hypotension(OR=2.1),surgical intervention(OR=2.8)and device removal(OR=4.8).Of this device removal(P=0.039)and recurrent admissions(P=0.017)were statistically significant.CONCLUSION This study highlights the associations of ECHO predictors and outcomes in patients with IE having multiple vegetations.ECHO features of moderate to severe regurgitation,presence of pacemaker lead,impaired LV relaxation,and elevated PASP and outcomes including recurrent admissions and device removal were found to be associated with multiple vegetations. 展开更多
关键词 ENDOCARDITIS ECHOCARDIOGRAPHY vegetations PREDICTORS OUTCOME
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A Fractal Method of Estimating Soil Structure Changes Under Different Vegetations on Ziwuling Mountains of the Loess Plateau,China 被引量:14
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作者 ZHAO Shi-wei SU Jing +3 位作者 YANG Yong-hui LIU Na-na WU Jin-shui SHANGGUAN Zhou-ping 《Agricultural Sciences in China》 CAS CSCD 2006年第7期530-538,共9页
Fractal method is a new method to estimate soil structure. It has been shown to be a useful tool in studies related to physical properties of soil as well as erosion and other hydrological processes. Fractal dimension... Fractal method is a new method to estimate soil structure. It has been shown to be a useful tool in studies related to physical properties of soil as well as erosion and other hydrological processes. Fractal dimension was used to study the soil structure in soil at different stages of vegetative succession on the Ziwuling Mountains. The land use and vegetation types included cultivated land, abandoned land, grassland, two types of shrub land, and three types of forests. The grassland, shrub land, and forested areas represented a continuum in vegetative succession that had occurred naturally, as the land was abandoned in 1862. Disturbed and undisturbed soil samples were collected from ten vegetation types from depths of 0-10, 10-20, and 20-30 cm on the Ziwuling Mountains, at a site with an elevation of about 1 500 m. Particle size distribution was determined by the pipette method and aggregate size distribution was determined by wet sieving. The results were used to calculate the particle and aggregate fractal dimension. The results showed that particle and aggregate fractal dimensions varied between vegetation types. There was a positive correlation between the particle fractal dimension and the weight of particles with diameter 〈 0.001 mm, but no relationship between particle fractal dimension and the other particle size classes. Particle fractal dimension was lower in vegetated soils compared to cropland and there was no consistent relationship between fractal dimension and vegetation type. Aggregate fractal dimension was positively correlated with the weight of 〉 0.25 mm aggregates. Aggregate fractal dimension was lower in vegetated soils compared with cropland. In contrast to particle fractal dimension, aggregate fractal dimension described changes in soil structure associated with vegetative succession. The results of this study indicate that aggregate fractal dimension is more effective in describing soil structure and function compared with particle fractal dimension. 展开更多
关键词 soil fractal dimension soil particle soil aggregate vegetation type Ziwuling Mountains
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Sensitivity analyses of different vegetations responding to climate change in inland river basin of China 被引量:8
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作者 Hou Peng Wang Qiao +3 位作者 Cao Guangzhen Wang Changzuo Zhan Zhiming Yang Bingfeng 《Journal of Geographical Sciences》 SCIE CSCD 2012年第3期387-406,共20页
Terrestrial ecosystem and climate system are closely related to each other. Faced with the unavoidable global climate change, it is important to investigate terrestrial ecosystem responding to climate change. In inlan... Terrestrial ecosystem and climate system are closely related to each other. Faced with the unavoidable global climate change, it is important to investigate terrestrial ecosystem responding to climate change. In inland river basin of arid and semi-arid regions in China, sensitivity difference of vegetation responding to climate change from 1998 to 2007 was analyzed in this paper. (1) Differences in the global spatio-temporal distribution of vegetation and climate are obvious. The vegetation change shows a slight degradation in this whole region. Degradation is more obvious in densely vegetated areas. Temperature shows a general downward trend with a linear trend coefficient of -1.1467. Conversely, precipitation shows an increasing trend with a linear trend coefficient of 0.3896. (2) About the central tendency response, there are similar features in spatial distribution of both NDVI responding to precipitation (NDVI-P) and NDVI responding to AI (NDVI-AI), which are contrary to that of NDVI responding to air temperature (NDVI-T). Typical sensitivity region of NDVI-P and NDVI-AI mainly covers the northern temperate arid steppe and the northern temperate desert steppe. NDVI-T typical sensitivity region mainly covers the northern temperate desert steppe. (3) Regarding the fluctuation amplitude response, NDVI-T is dominated by the lower sensitivity, typical regions of the warm temperate shrubby, selui-shrubby, bare extreme dry desert, and northern temperate meadow steppe in the east and temperate semi-shrubby, dwarf arboreous desert in the north are high response. (4) Fluctuation amplitude responses between NDVI-P and NDVI-AI present a similar spatial distribution. The typical sensitivity region mainly covers the northern temperate desert steppe. There are various linear change trend responses of NDVI-T, NDVI-P and NDVI-AI. As to the NDVI-T and NDVI-AI, which are influenced by the boundary effect of semi-arid and semi-humid climate zones, there is less correlation of their linear change tendency along the border. There is stronger correlation in other regions, especially in the NDVI-T in the northern temperate desert steppe and NDVI-AI in the warm temperate shrubby, selui-shrubby, bare, extreme and dry desert. 展开更多
关键词 VEGETATION CLIMATE satellite images sensitivity analyses inland river basin China
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Fractions and Bioavailability of Soil Inorganic Phosphorus in the Loess Plateau of China under Different Vegetations 被引量:5
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作者 WEI Xiaorong SHAO Mingan +2 位作者 SHAO Hongbo GAO Jianlun XU Gang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期263-270,共8页
Plants play an important role in soil phosphorus nutrition. However, the effect of plants on phosphorus nutrition in soils of the Loess Plateau of China is not well understood. This study was conducted to reveal the r... Plants play an important role in soil phosphorus nutrition. However, the effect of plants on phosphorus nutrition in soils of the Loess Plateau of China is not well understood. This study was conducted to reveal the relationships between plants and phosphorus' fractions and availability in the Loess Plateau of China. Twenty-two plant communities were surveyed and soil samples under different plant canopies were collected for the determination of soil properties and inorganic phosphorus fractionation. The results showed that Leguminosae and Lilaceae reduced pH and increased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies, while Labiatae and Rosaceae increased pH and decreased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies. The contents of Ca2P, CasP, AI-P and Fe-P were highly related with soil Oisen phosphorus. They were all higher in soils under Leguminosae and Lilaceae and lower in softs under Labiatae and Rosaceae. The results of this study indicate that Leguminosae and Lilaceae improved phosphorus nutrition in soils, yet Labiatae and Rosaceae impeded the improvement of phosphorus nutrition in soils under their canopies, which will be of more help to instruct vegetation restoration in the region and provide information for soil development. 展开更多
关键词 BIOAVAILABILITY FRACTION inorganic phosphorus VEGETATION soil development Loess Plateau
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Velocity distribution of flow with submerged flexible vegetations based on mixing-length approach 被引量:2
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作者 槐文信 韩杰 +3 位作者 曾玉红 安翔 钱忠东 Yu-lu LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期343-351,共9页
By choosing a PVC slice to simulate flexible vegetation, we carried out experiments in an open channel with submerged flexible vegetation. A 3D acoustic Doppler velocimeter (micro ADV) was used to measure local flow... By choosing a PVC slice to simulate flexible vegetation, we carried out experiments in an open channel with submerged flexible vegetation. A 3D acoustic Doppler velocimeter (micro ADV) was used to measure local flow velocities and Reynolds stress. The results show that hydraulic characteristics in non-vegetation and vegetation layers are totally different. In a region above the vegetation, Reynolds stress distribution is linear, and the measured velocity profile is a classical logarithmic one. Based on the concept of new-riverbed, the river compression parameter representing the impact of vegetation on river is given, and a new assumption of mixing length expression is made. The formula for time-averaged velocity derived from the expression requires less parameters and simple calculation, and is useful in applications. 展开更多
关键词 flexible vegetation PVC slice micro ADV mixing-length approach streamwise velocity distribution Reynolds stress river compression parameter
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Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate
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作者 Zhengchao Ren Lei Liu +1 位作者 Fang Yin Xiaoni Liu 《Forest Ecosystems》 SCIE CSCD 2024年第2期184-192,共9页
Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional pr... Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide. 展开更多
关键词 Potential natural vegetation Global warming Vegetation classification Predicted model CSCS
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Floral Diversity of Abandoned Mansions and the Influence of Soil Properties on These Unique Vegetations
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作者 Md. Tahidul Islam Md. Mahadiy Hasan +2 位作者 Md. Ashikur Rahman Laskar Subroto K. Das Tania Sultana 《American Journal of Plant Sciences》 2021年第10期1559-1600,共42页
Abandoned land and mansions are always a matter of curiosity to the human beings. They are treated as haunted places in many societies. In the present research, three decrepit abandoned mansions from the southern Bang... Abandoned land and mansions are always a matter of curiosity to the human beings. They are treated as haunted places in many societies. In the present research, three decrepit abandoned mansions from the southern Bangladesh were investigated to measure their floral diversity, physico-chemical properties of soil and the soil-plant interrelationship which is responsible for the diversification of wild flora within the regions. From Shannon and Simpson diversity indexes, it can be deducted that the floral diversity within the abandoned mansions ha</span><span style="font-family:"">s</span><span style="font-family:""> a<span style="color:red;"> </span>positive relationship with their territory size. The high values of Marg<span>alef’s and Menhinick’s species richness indexes confirmed that these areas are a rich source of a large number of plant species. A great variation in soil physico-chemical properties has been observed during the analysis. Soil organic matter, nitrogen, phosphorus, potassium & moisture contents were varied significantly from one quadrat to another in every site. Biplot analysis showed that the distribution of plant species in abandoned mansions </span></span><span style="font-family:"">is</span><span style="font-family:""> primarily determined by the organic matter, pH, moisture and potassium contents of soil. As t</span><span style="font-family:"">hese factors were present in versatile distribution within the studied regions, a great number of plants can grow in the same area simultaneously. So these areas should be protected from human intervention to proce</span><span style="font-family:"">ss</span><span style="font-family:""> natural selection and in situ conservation of plant species. 展开更多
关键词 Floral Diversity Abandoned Area Soil Properties VEGETATION
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A random walk simulation of scalar mixing in flows through submerged vegetations 被引量:14
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作者 梁东方 WU Xuefei 《Journal of Hydrodynamics》 SCIE EI CSCD 2014年第3期343-350,共8页
The scalar transport phenomena in vertical two-dimensional flows are studied using the random walk method. The established Lagrangian model is first applied to study the idealized longitudinal dispersion in open chann... The scalar transport phenomena in vertical two-dimensional flows are studied using the random walk method. The established Lagrangian model is first applied to study the idealized longitudinal dispersion in open channels, before being used to investigate the scalar mixing characteristics of the flows through submerged vegetations. The longitudinal dispersion coefficients of the fully-developed boundary layer flows, with and without vegetations, are calculated based on the positions of the particles. A convenient way of incorporating the effects of vegetations is proposed, where all the flow parameters are regarded to be continually distributed over the depth. The simulation results show high accuracy of the developed random walk method, and indicate that the new method of accounting for the vegetation effects is appropriate for all the test cases considered. The predicted longitudinal dispersion coefficients agree well with the measurements. The merit of the new method is highlighted by its simplicity and efficiency in comparison with the conventional method that assumes the discontinuous distribution of the flow parameters over the depth. 展开更多
关键词 random walk longitudinal dispersion submerged vegetations scalar mixing
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Response of soil moisture to vegetation restoration:A bibliometric synthesis
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作者 GAN Shao'an HAN Lei +3 位作者 LI Yabei CHANG Yuqing ZHANG Hanxiao TUO Fengwei 《中国水土保持科学》 北大核心 2026年第1期270-284,共15页
[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucid... [Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucidating the global response patterns of soil moisture to vegetation restoration and identifying research hotspots are critical for guiding ecological construction in arid regions.[Methods]We reviewed 6,152 articles concerning soil moisture and vegetation retrieved from the Web of Science platform.Using VOSviewer,we conducted analyses of keyword co-occurrence,publication trends,and research hotspots to systematically delineate the evolving trends in this field.[Results]The results indicate a significant increasing trend in the number of publications since 2000.Global research keywords are categorized into seven clusters,including vegetation,soil moisture,rainfall-erosion-infiltration,spatial heterogeneity,and climate change.In terms of highly cited papers in 2024,China and the United States maintain a significant lead.Global research demonstrates a strong dependency on typical regional geographical features(such as climate types and topography),exhibiting differentiated research focuses.Furthermore,studies extend beyond soil moisture itself to deeply couple with ecological processes such as vegetation restoration,soil respiration,carbon cycling,and hydrothermal conditions.[Conclusions]The long-term ecological effects of afforestation in arid regions remain unclear,and empirical data from key regions highlight the current urgency.Future research should integrate climate change dynamics,innovate monitoring methodologies,and deepen the understanding of regional differentiation to provide scientific support for the adaptive management of vegetation in arid regions. 展开更多
关键词 soil moisture VEGETATION bibliometric analysis VOSviewer
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An index for characterizing bioavailability and risk of metals in soil-vegetable systems
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作者 Lanqin YANG Yuechen YU +2 位作者 Yuanming WANG Biao HUANG Wenyou HU 《Pedosphere》 2026年第1期358-362,共5页
Dear Editor,With the growing food demands and the rapid development of intensive vegetable cultivation,the vegetable yield and planting area have increased to 230 million tons and 2.13 million hectares,respectively,in... Dear Editor,With the growing food demands and the rapid development of intensive vegetable cultivation,the vegetable yield and planting area have increased to 230 million tons and 2.13 million hectares,respectively,in China in 2021(MARAPRC,2023). 展开更多
关键词 METALS BIOAVAILABILITY RISK soil vegetable systems intensive vegetable cultivationthe
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Effects of wetland connectivity on plant communities and vegetation patterns in the Qaidam Basin
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作者 YUE Yifan MA Dengke +3 位作者 MA Yuanyuan KANG Wenrong ZHOU Guoying ZHAO Wenzhi 《Journal of Arid Land》 2026年第4期696-714,共19页
The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronou... The Qaidam Basin,a typical alpine arid inland basin on the northern Qinghai-Xizang Plateau,China,hosts wetland ecosystems that are strongly constrained by topography and extreme climate.These ecosystems exhibit pronounced spatiotemporal heterogeneity and fragmented distribution patterns,rendering them highly sensitive to environmental change.This study integrated Sentinel-2 remote sensing imagery with the SedInConnect model to delineate wetland patch distributions and calculate the Index of Connectivity(IC)values across the basin.Based on IC values,we stratified field sampling sites into high-,moderate-,and lowconnectivity gradient groups to analyze the relationships among plant community characteristics,vegetation spatial patterns,and wetland connectivity in the Qaidam Basin.Partial Least Squares Path Modeling(PLSPM)was further employed to quantify the driving mechanisms underlying wetland vegetation characteristics.The results revealed that wetland connectivity across the basin was generally low,with IC values up to 1.32 and displaying a west-to-east decreasing gradient.The west and northwest were characterized by relatively continuous high-connectivity wetland networks,while fragmented and low-connectivity wetlands predominated in the east and southeast.Connectivity regulated wetland vegetation patterns primarily by affecting patch size,fragmentation,and internal adjacency.High-connectivity areas had higher class area(CA),largest patch index(LPI),and area-weighted mean patch size(AREA_AM)than low-connectivity areas.Connectivity had the strongest effect on vegetation coverage,which declined sharply from 87.577%in highconnectivity areas to 12.152%in low-connectivity areas.Meanwhile,species diversity showed a moderately negative response to connectivity changes,whereas species evenness remained relatively unaffected.PLS-PM explained 78.300%and 67.500%of the variance in vegetation community and vegetation pattern,respectively.Climate played a dominant role in shaping vegetation characteristics,with significant negative effects on both vegetation community and pattern.Topography influenced vegetation indirectly through climate,and connectivity was influenced by both drivers and exerted positive effects on vegetation community and pattern.This study reveals the multi-pathway driving mechanisms underlying vegetation pattern formation in alpine wetlands,providing a theoretical foundation and decision-support framework for the scientific conservation and adaptive management of wetlands in the Qaidam Basin. 展开更多
关键词 connectivity gradient wetland vegetation vegetation pattern community characteristics driving mechanisms
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Mapping vegetation phenology and its response to climate change in Southwest China using solar-induced chlorophyll fluorescence
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作者 TANG Feng GE Zhongxi +5 位作者 TANG Bohui FANG Liuyang ZHANG Zhen FAN Dong CHEN Junyi ZHU Xinming 《Journal of Mountain Science》 2026年第1期97-117,共21页
Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon ... Accurate phenological information is essential for measuring ecosystem dynamics and carbon uptake.Southwest China is one of the country's largest terrestrial carbon sink regions and plays a crucial role in carbon peaking and neutrality.However,its complex terrain,fragile ecosystem,and variable climate challenge carbon sink stability.Vegetation phenology significantly impacts carbon absorption and release,making accurate phenological data essential for understanding carbon sequestration dynamics.The widespread distribution of evergreen forests and their weak seasonal variation in canopy introduce significant uncertainties in extracting phenology using traditional remote sensing information in this region.These limitations can lead to inaccurate assessments of carbon sink dynamics.Therefore,precise phenology extraction and analysis are vital for improving ecosystem dynamics and the carbon cycle in Southwest China.Firstly,we employed different ways to evaluate the ability of solar-induced chlorophyll fluorescence(SIF)and traditional remote sensing information to extract phenology.Secondly,based on SIF,we analyzed the spatial and temporal changes in the start of the growing season(SOS),the end of the growing season(EOS),and the length of the growing season(LOS)from 2001 to 2020.Finally,we systematically analyzed the response of SOS and EOS to five preseason climatic factors.The results showed that(1)SIF outperformed traditional remote sensing information in extracting phenology.(2)Vegetation phenology exhibited significant spatial heterogeneity.Moreover,SOS,EOS,and LOS showed trends of advancement,delay,and extension both overall and across all vegetation types.(3)Precipitation was the main factor influencing SOS,while surface downward solar radiation and mean temperature were the main factors affecting EOS,and the phenology of different vegetation types showed a great difference in response to preseason climate factors.These findings improve our understanding of vegetation phenology and its dynamics over Southwest China. 展开更多
关键词 Carbon stability Mountain area Vegetation phenology Evergreen vegetation Solar induced chlorophyll fluorescence
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Spatio-Temporal Dynamics of the Vegetation Cover in a Northern Forest of Morocco:Izarene Forest
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作者 Fatima-Zahra Elmassamri Said Laaribya 《Research in Ecology》 2026年第1期79-98,共20页
The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based o... The study presents an analysis of the spatiotemporal evolution of vegetation cover in the Izarene forest,using LANDSAT satellite images collected for the years 1984,2003,and 2022.The methodological approach is based on the use of ArcGIS 10.8 software for processing multispectral images,as well as the calculation of the Normalized Difference Vegetation Index(NDVI),which enables the observation of variations in vegetation cover over time.The findings show that biodiversity is pretty abundant,but they also show that some places with low vegetation density are under a lot of stress.Due in large part to overuse of natural resources,uncontrolled human activity,and environmental factors,these regions seem to be more vulnerable to degradation.However,a decrease in deforestation over the past 20 years is revealed by comparing the two periods(1984–2003 and 2003–2022).The participation of governmental agencies,especially the Department of Water and Forests,through concrete projects like reforestation,forest fire prevention,and awareness-raising campaigns among local communities,is responsible for this progress.In several areas,these measures have stabilized or even improved the state of the vegetation.The analysis emphasizes how crucial sustainable,integrated,and participatory management is to protecting the Izarene forest,which is a significant resource for maintaining the region’s ecological balance. 展开更多
关键词 FOREST Izarene Vegetation Cover DYNAMICS DEGRADATION Morocco
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Dynamic vegetation change response to topography based on Landsat observations in the Tianshan Mountains,China during 2000–2022
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作者 WEN Di LI Jun +2 位作者 XU Weifeng CHEN Zhixiang PENG Dailiang 《Journal of Arid Land》 2026年第3期501-523,共23页
In the arid regions of Northwest China,vegetation cover plays a crucial role in maintaining unique terrestrial ecosystems.Vegetation growth is highly sensitive to variations in topographical factors,and the influence ... In the arid regions of Northwest China,vegetation cover plays a crucial role in maintaining unique terrestrial ecosystems.Vegetation growth is highly sensitive to variations in topographical factors,and the influence of topography on vegetation cover has attracted increasing attention.This study analyzed vegetation dynamics and their relationship with topography in the Tianshan Mountains of China using Landsat Normalized Difference Vegetation Index(NDVI)data during 2000–2022 and Shuttle Radar Topography Mission(SRTM)-derived topographical factors(elevation,slope,and aspect).Theil-Sen slope estimation and Mann-Kendall trend tests were applied to quantify temporal changes in vegetation,while a terrain area correction coefficient(K)was used to assess spatial associations of vegetation with topography.Random Forest(RF)regression and SHapley Additive exPlanations(SHAP)analysis evaluated the relative importance of topographical factors in shaping vegetation cover(multi-year mean NDVI)distribution.Key findings included that over the 23-a period,59.46%of the vegetated area exhibited significant improvement(P<0.05),with the southern Tianshan Mountains showing the most pronounced increase(70.59%),whereas vegetation degradation(3.10%)was primarily concentrated in river valleys with intensive human activities.RF-SHAP analysis revealed that elevation is the primary driver of vegetation cover patterns,explaining 52.00%of the NDVI variation.The peak NDVI(0.42)occurred at elevations between 2800 and 3200 m.Slope and aspect also significantly influenced vegetation distribution,and higher NDVI values and greater improvement trends were observed on shady(north-facing)slopes compared to sunny(south-facing)slopes.K-index analysis indicated pronounced vegetation change—both degradation and improvement—in areas with elevations between 1100 and 2800 m and slopes exceeding 5°,particularly on sunny slopes.Low-elevation desert areas in the southern Tianshan Mountains were highly susceptible to degradation.This study underscores the critical role of topography in regulating vegetation cover and its spatiotemporal dynamics,providing a scientific basis for sustainable management of arid mountain ecosystems. 展开更多
关键词 TOPOGRAPHY vegetation dynamics Normalized Difference Vegetation Index(NDVI) Random Forest(RF) SHapley Additive exPlanations(SHAP) Tianshan Mountains
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Basic research and industrial development status of suancai in Northeast China:history,microflora diversity,processing technology,nutrition and safety
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作者 Qianqian Wang Jingbo Yang +7 位作者 Yuqi Wang Meiru Xie Xiaoxi Qi Ramnarain Ramakrishna Libo Liu Wenkui Guo Guofang Zhang Chun Li 《Food Science and Human Wellness》 2026年第1期13-27,共15页
Suancai has a lengthy history and a wide range of categories,which has some influence on the pickled diet culture around the world.Suancai production is transitioning to a large-scale,standardized production due to th... Suancai has a lengthy history and a wide range of categories,which has some influence on the pickled diet culture around the world.Suancai production is transitioning to a large-scale,standardized production due to the growth of the market.It has a unique flavor and is rich in nutrients,and its abundance of free amino acids,vitamins and phenolics has many positive effects on the human body.This review gives the types and history of suancai,as well as its impact on the world’s pickled culture.The changes in nutritional composition and flavor of suancai during fermentation are summarized.It presented the production technology and influencing factors of the northeast suancai,examined the quality and safety issues in suancai,and put forth some ideas and opinions on the standardization development of the suancai industry.It also summarized the geographic distribution and flora diversity of pickles around the world.In order to provide some knowledge and guidance for the promotion of modern industrial production in the suancai industry. 展开更多
关键词 Fermented vegetables Microbial community Process NUTRITION SAFETY
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s... Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests. 展开更多
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Light Regulation across Strawberry Growth Stages:A Comprehensive Review
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作者 Geng Zhang Xiangyu Ding +7 位作者 Zidan Wen Chao Liu Duyen T.P.Nguyen Jinxiu Song Zejin Zhang Zhiming Yan Yuanhua Wang Zhengnan Yan 《Phyton-International Journal of Experimental Botany》 2026年第2期1-21,共21页
As a pivotal environmental factor,light,comprising intensity,photoperiod,and spectrum,governs the entire life cycle of strawberries by mediating alterations in the plant’s morphological,physiological,and biochemical ... As a pivotal environmental factor,light,comprising intensity,photoperiod,and spectrum,governs the entire life cycle of strawberries by mediating alterations in the plant’s morphological,physiological,and biochemical traits.Although extensive research has been conducted on light-mediated growth regulation in horticultural crops,most reviews focus primarily on leafy and fruiting vegetables,with limited attention given to berry crops such as strawberries.Additionally,most existing reviews concentrate on one or several growth stages,failing to systematically characterize light’s effects throughout the entire growth cycle and postharvest stage.This review briefly summarizes the regulatory roles of light across key stages of strawberry growth,including seedling propagation,vegetative growth,reproductive growth,and postharvest stages.It seeks to address the knowledge gap by systematically organizing research findings across these developmental phases.The integrated analysis provides a theoretical foundation for designing stage-specific lighting strategies to improve strawberry yield and quality. 展开更多
关键词 Light intensity light spectrum STRAWBERRY seedling propagation vegetative growth reproductive growth POSTHARVEST
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Urban expansion drives both loss and compensation in city vegetation productivity
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作者 Xinyue Liu Tianshan Zha +6 位作者 Charles P.-A.Bourque Peng Liu Hongxian Zhao Tingshan Li Xinhao Li Yun Tian Xin Jia 《Journal of Environmental Sciences》 2026年第2期591-599,共9页
Urbanization alters vegetation productivity by both direct(ωd)and indirect(ω_(i))effects.The direct effect is from the change of vegetated area indicated by impervious surface intensity(ISI),while indirect effects a... Urbanization alters vegetation productivity by both direct(ωd)and indirect(ω_(i))effects.The direct effect is from the change of vegetated area indicated by impervious surface intensity(ISI),while indirect effects arise from changes in urban environmental factors,such as near-surface air temperatures,precipitation,urban heat island(UHI)intensity,and population density(POP).The respective contributions ofω_(d) andω_(i) to vegetation net primary productivity(NPP)under various phases of urbanization are not well quantified.Using multisource remote-sensing data from 1990 to 2020,we analyzed the spatiotemporal variation in urban expansion and the effect thatω_(d) andω_(i) had on NPP in the megalopolis of Beijing,China,over 5-year intervals.During this period,Beijing underwent significant planar expansion rates of about 58.9 km^(2)/yr.Annual mean loss of NPP byω_(d) was estimated to be about 77.1 g C/(m^(2)·yr)during the 1990-2020 period,while annual mean improvement to NPP byω_(i) amounted to an increase of 28.9 g C/(m^(2)·yr).The NPP losses were partially offset by NPP improvements in the order of 18.6%-69.3%.The impact of forcing variables on NPP varied spatially.Air temperature,precipitation,UHI,POP,and ISI explained about 13.8%,23.2%,23.7%,14.7%,and 24.6%of the spatial variation in NPP.The impact of air temperature on NPP was related to available moisture,negatively affecting NPP in regions with water deficits.Our findings demonstrate the dual impact of urbanization on vegetation and underscore the necessity for spatially adaptive ecological management strategies in regions experiencing rapid urban growth. 展开更多
关键词 Impervious surface intensity Vegetation productivity COMPENSATION Spatial heterogeneity
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