An interactive simulation model is established based on the methodology of 'sensitivity model' (SM) during the cooperative research process between the founders of SM and the authors. And the conceptual framew...An interactive simulation model is established based on the methodology of 'sensitivity model' (SM) during the cooperative research process between the founders of SM and the authors. And the conceptual framework of SM is developed into the interactively qualitative and quantitative simulation model presented in this paper, which makes it possible to break down a complex urban ecosystem into simple and visual quantitative or qualitative relationships between the factors. By studying the dynamic responses of the system to the changes of the inputs and parameters of the model, future trends in urban development can be predicted and strategies formulated. The whole process is realized on micro-computer in the course of man-computer interaction. Its potential use is shown in a case of Tianjin City.展开更多
This paper systematically combs 416 literature on urban ecosystem services (UES) in China and other countries from 2010 to 2020,and carefully interprets the abstracts of 383 effective literature.According to the class...This paper systematically combs 416 literature on urban ecosystem services (UES) in China and other countries from 2010 to 2020,and carefully interprets the abstracts of 383 effective literature.According to the classification method of the research perspectives of ecosystem services proposed by Luederitz C,the literature is divided into six categories:ecology,governance,methods / tools / guidelines,social networking,economy and planning,and Excel and CiteSpace software were used for data statistical analysis and visual processing.The research shows that:in terms of research perspectives,foreign researches are evenly distributed in six categories:ecology,governance,methods / tools / guidelines,social networking,economy and planning,while domestic research perspectives are relatively concentrated in three categories:economy,governance,methods / tools / guidelines,and the proportion of economic category is particularly significant.In terms of research contents,there are more studies on climate governance,decision-making mechanism and method innovation abroad,while there are more studies on the measurement of carbon sequestration and oxygen releasing,the evaluation of ecological security pattern and the quantitative evaluation of UES’s economic value in China,and there are less studies on institutional organization structure and policy tools,innovative methods of UES’s value evaluation,the potential role of UES on some social phenomena,the relationship between UES and residents’ behavior and perception.展开更多
Background: Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services(ES) ar...Background: Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services(ES) are an important response. Given the limited resources available for assessing urban ES in many cities, practical approaches for integrating ES in decision-making process are needed.Methods: We apply remote sensing techniques(integrating LiDAR data with high-resolution multispectral imagery)and combined these with supplementary spatial data to develop a replicable approach for assessing the role of urban vegetation(including invasive alien plants) in providing ES and ecosystem disservices(EDS). We identify areas denoting potential management trade-offs based on the spatial distribution of ES and EDS using a local-scale case study in the city of Cape Town, South Africa. Situated within a global biodiversity hotspot, Cape Town must contend with widespread invasions of alien plants(especially trees and shrubs) along with complex socio-political challenges. This represents a useful system to examine the challenges in managing ES and EDS in the context of urban plant invasions.Results: Areas of high ES provision(for example carbon sequestration, shade and visual amenity) are characterized by the presence of large trees. However, many of these areas also result in numerous EDS due to invasions of alien trees and shrubs – particularly along rivers, in wetlands and along the urban edge where tall alien trees have established and spread into the natural vegetation(for example increased water consumption, increased fire risk and reduced soil quality). This suggests significant trade-offs regarding the management of species and the ES and EDS they provide.Conclusions: The approach applied here can be used to provide recommendations and to guide city planners and managers to fine-tune management interventions at local scales to maximise the provision of ES.展开更多
The urban ecosystem possesses dissipating structures that can absorb substances and energy from the external environment and export products and wastes to maintain order within the system. Given these circumstances, t...The urban ecosystem possesses dissipating structures that can absorb substances and energy from the external environment and export products and wastes to maintain order within the system. Given these circumstances, this paper analyzed the ability of the urban ecosystem in Guangzhou City to sustain development from the perspective of entropy. The research was carried out in three steps. First, an evaluation index system that considers the ability of the urban ecosystem for sustainable development was formed based on the struc- tures and functions of the urban ecosystem and the change in the entropy of the urban so- cioeconomic ecosystem. Second, the sustainable development ability assessment model for the urban ecosystem was built using information entropy. Last, by combining the time series variation of the evaluation indicators with the entropy weights, this paper analyzed the influ- ence of the combined factors on the sustainable development ability of the urban ecosystem in Guangzhou and suggested some measures to promote the sustainable development of the urban ecosystem in Guangzhou. The conclusions of this study can be summarized as follows: (1) The urban ecosystem has developed in an orderly and healthy direction, with effective control over the urban environmental pollution problems in Guangzhou between 2004 and 2010. (2) The sustainable development ability of the urban ecosystem had been on an up- ward trend in Guangzhou during the study period. The ability of the natural urban ecosystem to support the urban socioeconomic ecosystem increased continuously, and the improved ecoenvironment enhanced the harmony and vitality of the urban ecosystem in Guangzhou.展开更多
Wetland ecosystems, particularly the mangrove forest, are the primary wild habitat of heronry birds. However, urban ecosystems have become a favorite breeding habitat of these birds. To provide inputs into the habitat...Wetland ecosystems, particularly the mangrove forest, are the primary wild habitat of heronry birds. However, urban ecosystems have become a favorite breeding habitat of these birds. To provide inputs into the habitat management for conservation of these birds, we investigated the quantitative and qualitative characteristics of nesting trees of heronry birds in the urban environment of the North Kerala region of peninsular India. Census on nesting trees was done in 3 major microhabitats of the urban ecosystem: avenues of national highways and towns, nonresidential plots, and residential areas apart from the mangrove islets in the peri-urban locality. The study found that 174 trees of 22 species hosted 1,928 heronry bird nests in the urban habitats; mangrove forests, although plentiful in the study area, hosted only about 20% of the total nests encountered in the study. Rain trees Samanea saman (43.7%) were the most available nesting tree. The greatest number of nests and nesting trees were encountered on the roads of urban areas, followed by nonresidential areas and residential areas. The differences in the observed frequencies of nesting trees in 3 microhabitats and in 3 types of roads (national highways 〉 state highways 〉 small pocket road) were significant. Canopy spread, girth size, and quality of the trees predicted the tree selection of the heronry birds in urban environments. Therefore, we recommend proper management and notification of the identified nesting trees as protected sites for the conservation of herorny birds.展开更多
In the light of the study of domestic and foreign ur-ban ecosystem,this article puts forward a set of ideological systemsfor the forecast,evaluation and tactic,and conducts initial primaryexploration of its forecast a...In the light of the study of domestic and foreign ur-ban ecosystem,this article puts forward a set of ideological systemsfor the forecast,evaluation and tactic,and conducts initial primaryexploration of its forecast and evaluation methods.展开更多
Urban parks are an important part of urban ecosystems and play an important role in biodiversity conservation.However,it is still unclear how park characteristics aff ect plant diversity which could hinder the conserv...Urban parks are an important part of urban ecosystems and play an important role in biodiversity conservation.However,it is still unclear how park characteristics aff ect plant diversity which could hinder the conservation of urban biodiversity due to the ineff ective design of urban parks.The diversity of woody plants in 33 parks of Changchun,China,was measured with plot measurements and linked with urban park characteristics(e.g.,size and age of the park)to uncover the relationship between them.The results show that urban woody plant species were abundant,with 98 species belonging to 51 genera and 26 families in the snow climate city of Changchun.The variation in woody plant diversity was largely explained by internal patch characteristics(e.g.,size,age,shape),and external factors surrounding the park(e.g.,land use type and socioeconomic level)accounted for only 16.0%in our study.For internal patch characteristics,older urban parks with larger areas demonstrated a richer level of plant diversity and increased nonlinearly with increasing park area.The threshold size signifi cantly aff ecting plant diversity variation was approximately 30 ha.Plant diversity had positive linear relationships with the ages of urban parks,supporting the legacy eff ect.In addition,woody plant diversity nonlinearly decreased with increasing park shape index,which suggested that the plant diversity could also be increased by optimizing the park shape.Regarding the external factors surrounding parks,the spatial distribution of woody plant diversity varied greatly from the urban center to the suburbs.House prices around the park had positive linear relationships with woody plant diversity in parks,supporting the luxury eff ect.However,building and road proportions,and green space proportion had no relationship with plant diversity in parks.This study can provide a robust reference for enriching plant diversity in urban parks,thus improving the development of urban sustainable cities.展开更多
Microorganisms play a key role in aquatic ecosystems.Recent studies show that keystone taxa in microbial community could change the community structure and function.However,most previous studies focus on abundant taxa...Microorganisms play a key role in aquatic ecosystems.Recent studies show that keystone taxa in microbial community could change the community structure and function.However,most previous studies focus on abundant taxa but neglected low abundant ones.To clarify the seasonal variation of bacterial and microalgal communities and understand their synergistic adaptation to diff erent environmental factors,we studied the bacterial and eukaryotic phytoplankton communities in Fenhe River that runs through Taiyuan City,central China,and their seasonal co-occurrence patterns using 16S and 18S rDNA sequencing.Results indicate that positive interaction of eukaryotic phytoplankton network was more active than negative one except winter,indicating that the cooperation(symbiotic phenomenon in which phytoplankton are interdependent and mutually benefi cial)among them could improve the adaption of microbial community to the local environmental changes and maintain the stability of microbial network.The main genera that identifi ed as keystone taxa in bacterial network were Salinivibrio and Sphingopyxis of Proteobacteria and they could respond to the variation of nitrite and make use of it,while those that identifi ed as keystone taxa in eukaryotic phytoplankton network were Pseudoschroederia and Nannochloris,and they were more susceptible to nitrate and phosphate.Mychonastes and Cryptomonas were closely related to water temperature.However,the loss of the co-occurrence by environmental factor changes aff ected the stability of network structure.This study provided a reference for analyzing relationship between bacteria and eukaryotic phytoplankton and revealing potential importance of keystone taxa in similar ecological domains in carbon,nitrogen,and phosphorus dynamics.展开更多
Ecosystem services of urban green spaces play an important role in the sustainable development of the urban ecosystem. How to quantify the ecological benefits of urban green spaces and evaluate their ecological servic...Ecosystem services of urban green spaces play an important role in the sustainable development of the urban ecosystem. How to quantify the ecological benefits of urban green spaces and evaluate their ecological services is a hot topic in related fields. Currently, with the advancement of science and technology, the assessment method has been developed from the traditional ones such as the Council of Tree and Landscape Appraisers(CTLA) method, afforestation cost method, and carbon tax method to CITYgreen and i-Tree. The latter two models have been widely used in countries of Europe and America, while the use of i-Tree has not been promoted in China. In this paper, i-Tree Eco(UFORE) was selected for research, and its application in the assessment of the ecosystem services of urban green spaces, including energy saving, air quality improvement, interception of rainwater, and aesthetic benefits, were analyzed. This study aims to provide a theoretical and scientific basis for the introduction and localization of i-Tree, as well as its generalization in the assessment of forest ecosystem services domestically.展开更多
As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis a...As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis and expert knowledge gathered within COST Action FP1204 GreenInUrbs,we proposed a classification of urban forest EESs into three categories:(A)regulation of air,water,soil and climate;(B)provisioning of habitat quality;and(C)provisioning of other goods and services.Each category is divided into EES types:(a)amelioration of air quality;restoration of soil and water;amelioration of the microclimate;removal of CO2 from the air;(b)provision of habitat for biodiversity;support for resilient urban ecosystems;provision of genetic diversity;and(c)provision of energy and nutrients;provision of grey infrastructure resilience.Each EES type provides one or more benefits.For each of these 12 benefits,we propose a set of indicators to be used when analyzing the impacts on the identified EESs.Around half of the 36 indicators are relevant to more than one single benefit,which highlights complex interrelationships.The indicators of wider applicability are tree and stand characteristics,followed by leaf physical traits and tree species composition.This knowledge is needed for the optimization of the EESs delivered by urban forests,now and in the future.展开更多
Urban planning has become a widely concern for minimizing the negative effects of urban expansion on terrestrial ecosystems. We developed an interdisciplinary modeling framework to evaluate the effectiveness and short...Urban planning has become a widely concern for minimizing the negative effects of urban expansion on terrestrial ecosystems. We developed an interdisciplinary modeling framework to evaluate the effectiveness and shortcomings of urban expansion management strategies. A three-step method was applied to Yinchuan Plain in the northwestern of China, including(1)analyzing the relationship between landscape pattern and ecosystem service values through mathematical statistics;(2) predicting landscape pattern and ecosystem services change under different scenarios based on cellular automaton model(SLEUTH-3r model); and(3) designing and validating optimized scenario through integrating historical analysis experiments and future multi-comparison suggestions. Results have suggested that landscape composition and configuration can significantly affect regional ecosystem service values, especially the connectivity and shape of landscape. Compact urban growth policy and medium environment protection policy are the appropriate setting for urban expansion plan. Optimization validation of the combined designed scenario implied the reliability of this method. Our results highlighted the significance of integrating application of landscape pattern analysis, ecosystem service value evaluation,model simulation and multi-scenario prediction in urban planning.展开更多
China is undergoing a rapid urbanization process,and urbanization will have a direct impact on regional ecosystems and affect regional ecosystem services.Considering the mountainous counties in Southwestern China as t...China is undergoing a rapid urbanization process,and urbanization will have a direct impact on regional ecosystems and affect regional ecosystem services.Considering the mountainous counties in Southwestern China as the research object,this study reveals the spatial clustering characteristics of four typical ecosystem services(food production,soil conservation,water yield and carbon sequestration)as well as the trade-offs and synergies among ecosystem services in different urbanized areas.At the same time,piecewise linear regression is used to determine the threshold of the influence of urbanization on ecosystem services.The results indicate that:1)There are spatial autocorrelations among the four typical ecosystem services;with strong clustering characteristics,the positive correlation types are"clustered"locally;and with significant spatial heterogeneity,the negative correlation types are scattered and mainly appear in the highly urbanized area.2)There are also remarkable differences in the relationship among various ecosystem services in different urbanized areas,and in particular,there are marked trade-offs between food production and carbon sequestration in the moderately urbanized area and the highly urbanized area.However,there are synergies between them in the lowly urbanized area.3)With an increase in the compounded night light index(CNLI),water yield,carbon sequestration,food production and overall ecosystem services values present an increasing-decreasing trend,the soil conservation function value shows a decreasing-increasing trend.The response of water yield,carbon sequestration,food production,and overall ecosystem services to the compounded night light index(CNLI)has a threshold of 1.2642,1.4833,1.3388,1.5146 and 1.2237,respectively.Based on the detected relationships between urbanization and ecosystem services,this study provides a theoretical reference for the selection of urbanization development models in key ecological functional areas.展开更多
The relationship between ecosystem services and urban phytodiversity is being studied in the Moukonzi-Ngouaka district of Brazzaville. Urban forestry, a source of well-being for the inhabitants, is associated with soc...The relationship between ecosystem services and urban phytodiversity is being studied in the Moukonzi-Ngouaka district of Brazzaville. Urban forestry, a source of well-being for the inhabitants, is associated with socio-cultural foundations. The surveys concern flora, ethnobotany, socio-economics and personal interviews. The 60.30% naturalized flora is heterogeneous and closely correlated with traditional knowledge. The Guineo-Congolese endemic element groups are 39.27% of the taxa, of which 3.27% are native to Brazzaville. Ethnobotany recognizes 48.36% ornamental taxa;28.36% food taxa;and 35.27% medicinal taxa. Some multiple-use plants are involved in more than one field. The supply service, a food and phytotherapeutic source, provides the vegetative and generative organs. Of the 52.31% of recognized taxa, 33.45% essentially provide leaves and 18.50% fruits. The main obsession of plant introduction being 1) food and phytotherapeutic, and 2) aesthetic, obscures other ecosystem services such as fuelwood and income, provided by NTFPs, pillars of poverty alleviation.展开更多
Sustainable urban forest management is still an evolving concept, particularly as it pertains to a sustainable supply of ecosystem benefits and management planning. Urban forestry maintains a greater human dimension c...Sustainable urban forest management is still an evolving concept, particularly as it pertains to a sustainable supply of ecosystem benefits and management planning. Urban forestry maintains a greater human dimension component than traditional timber-oriented rural forestry because urban trees grow in city centers and neighborhoods, supplying critical ecosystem benefits to the population centers. The overall goal of this study was to evaluate the relationship of urban forest stand structure and its temporal dynamics with the sustainable supply of ecosystem benefits in university environments. Individual tree data were collected from a completed inventory, while the i-Tree Eco model was used to generate ecosystem benefits data from the Clemson urban forest. The cumulative-benefits supply curve had an inverted J-shaped curve, but the average supply curve had a negative slope against the species richness. Likewise, individual tree variables total height, DBH, leaf area, and crown height strongly correlated with the total ecosystem services supply. Based on the temporal supply trends, the study area trees were broadly segmented into three groups: establishment, growth, and legacy, with 65%, 31%, and 4% frequency distribution, respectively. Urban forest managers need to identify forest management goals and preferred ecosystem benefits among the urban communities to guide the required forest structure and dynamics to ensure a sustainable and functioning urban forest.展开更多
During land transformation process in the human history, naturalized plants were introduced to several land use patterns by the different ways of plant itself. Including some naturalized plants that had been contribut...During land transformation process in the human history, naturalized plants were introduced to several land use patterns by the different ways of plant itself. Including some naturalized plants that had been contribute to land restoration, many naturalized plants have been invaded to original habitat or landscape for native plants. Once the plants were colonized, they extend their area and population size. Urban developed areas often give an important role of source habitat for naturalized plants and expanding their population size. In recent, this situation is appearing as one of environmental problems about the urban landscape management controlling the naturalized plants that invaded in the developed area and conserving the native vegetation. This paper is focusing on relationships between distribution of habitat of naturalized plants and landscape patch in urban area in Seoul. Gangdong-Gu, one of the administrative areas in Seoul was selected for this study. We examined the recent land use change using LANDSAT TM data and spreading of the representative naturalized plants (Robinia pseudoacacia and Eupatorium rugosum) by Seoul Biotope Mapping Project and field survey in 1999. As a result, these two species were often occurred in the same habitat and distributed in forest edge disturbed by man. Their distribution patterns were related to landscape indices (patch size and shape) in the forest edge.展开更多
Colombo is the capital of Sri Lanka and the only wetland city in South Asia under the Ramsar Convention. Crow Island Beach Park and associated coastal area belong to the Colombo urban coastal wetland ecosystems. Crow ...Colombo is the capital of Sri Lanka and the only wetland city in South Asia under the Ramsar Convention. Crow Island Beach Park and associated coastal area belong to the Colombo urban coastal wetland ecosystems. Crow Island wetland contributes diverse habitats for numerous flora and fauna species. The present study was conducted to assess the status of floral diversity in the Crow Island Beach Park and associated coastal ecosystem during the months of August to October 2021. Study area is divided in to three sites (A, B, C). Line transects method and field observations were used in the study. This coastal wetland consists of mosaic of five major vegetation types: Herbaceous, tree, shrub, creeper, grass and other than that marine algae namely<em> Chaetomorpha antennina</em>, <em>Rhizoclonium africanum</em>, <em>Ulva compressa</em> belonging to chlorophyta (green algae) and <em>Grateloupia</em> <em>lithophila</em> belonging to rhodophyta (red algae) were found in the study area. A total number of 102 flora species belonging to 50 families were recorded from the study area. There were two true mangrove species and 16 mangrove associated species in the study sites. Out of the 102 plant species 46 were recognized and documented as plants with medicinal values. Shannon-Wiener diversity indexes for mangrove and mangrove associated species were recorded as 2.378, 2.304 and 1.676 in site A, B and C respectively. Simpson’s diversity index for mangrove and mangrove associated species was recorded as 0.889, 0.874 and 0.735 respectively in site A, B and C and Jaccard index of similarity between three study sites showed high values ranging from 41% to 69% for mangrove and mangrove associated species.展开更多
基金It is a part of CERP (Cooperative Ecologioal Research Project) supported by UNESCO.
文摘An interactive simulation model is established based on the methodology of 'sensitivity model' (SM) during the cooperative research process between the founders of SM and the authors. And the conceptual framework of SM is developed into the interactively qualitative and quantitative simulation model presented in this paper, which makes it possible to break down a complex urban ecosystem into simple and visual quantitative or qualitative relationships between the factors. By studying the dynamic responses of the system to the changes of the inputs and parameters of the model, future trends in urban development can be predicted and strategies formulated. The whole process is realized on micro-computer in the course of man-computer interaction. Its potential use is shown in a case of Tianjin City.
基金supported by the National Social Science Fond of China (Grant No. 19XJY003)。
文摘This paper systematically combs 416 literature on urban ecosystem services (UES) in China and other countries from 2010 to 2020,and carefully interprets the abstracts of 383 effective literature.According to the classification method of the research perspectives of ecosystem services proposed by Luederitz C,the literature is divided into six categories:ecology,governance,methods / tools / guidelines,social networking,economy and planning,and Excel and CiteSpace software were used for data statistical analysis and visual processing.The research shows that:in terms of research perspectives,foreign researches are evenly distributed in six categories:ecology,governance,methods / tools / guidelines,social networking,economy and planning,while domestic research perspectives are relatively concentrated in three categories:economy,governance,methods / tools / guidelines,and the proportion of economic category is particularly significant.In terms of research contents,there are more studies on climate governance,decision-making mechanism and method innovation abroad,while there are more studies on the measurement of carbon sequestration and oxygen releasing,the evaluation of ecological security pattern and the quantitative evaluation of UES’s economic value in China,and there are less studies on institutional organization structure and policy tools,innovative methods of UES’s value evaluation,the potential role of UES on some social phenomena,the relationship between UES and residents’ behavior and perception.
基金Funding for this work was provided by the DST-NRF Centre of Excellence for Invasion Biology and the Working for Water Programme through their collaborative research project on “Integrated Management of invasive alien species in South Africa”the National Research Foundation,South Africa(grant85417 to DMR)
文摘Background: Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services(ES) are an important response. Given the limited resources available for assessing urban ES in many cities, practical approaches for integrating ES in decision-making process are needed.Methods: We apply remote sensing techniques(integrating LiDAR data with high-resolution multispectral imagery)and combined these with supplementary spatial data to develop a replicable approach for assessing the role of urban vegetation(including invasive alien plants) in providing ES and ecosystem disservices(EDS). We identify areas denoting potential management trade-offs based on the spatial distribution of ES and EDS using a local-scale case study in the city of Cape Town, South Africa. Situated within a global biodiversity hotspot, Cape Town must contend with widespread invasions of alien plants(especially trees and shrubs) along with complex socio-political challenges. This represents a useful system to examine the challenges in managing ES and EDS in the context of urban plant invasions.Results: Areas of high ES provision(for example carbon sequestration, shade and visual amenity) are characterized by the presence of large trees. However, many of these areas also result in numerous EDS due to invasions of alien trees and shrubs – particularly along rivers, in wetlands and along the urban edge where tall alien trees have established and spread into the natural vegetation(for example increased water consumption, increased fire risk and reduced soil quality). This suggests significant trade-offs regarding the management of species and the ES and EDS they provide.Conclusions: The approach applied here can be used to provide recommendations and to guide city planners and managers to fine-tune management interventions at local scales to maximise the provision of ES.
基金Project funded by both the Bureau of Science and Information Technology of Guangzhou Municipal Governmentthe Key Laboratory of Offshore Oil Exploration and Development in 2011
文摘The urban ecosystem possesses dissipating structures that can absorb substances and energy from the external environment and export products and wastes to maintain order within the system. Given these circumstances, this paper analyzed the ability of the urban ecosystem in Guangzhou City to sustain development from the perspective of entropy. The research was carried out in three steps. First, an evaluation index system that considers the ability of the urban ecosystem for sustainable development was formed based on the struc- tures and functions of the urban ecosystem and the change in the entropy of the urban so- cioeconomic ecosystem. Second, the sustainable development ability assessment model for the urban ecosystem was built using information entropy. Last, by combining the time series variation of the evaluation indicators with the entropy weights, this paper analyzed the influ- ence of the combined factors on the sustainable development ability of the urban ecosystem in Guangzhou and suggested some measures to promote the sustainable development of the urban ecosystem in Guangzhou. The conclusions of this study can be summarized as follows: (1) The urban ecosystem has developed in an orderly and healthy direction, with effective control over the urban environmental pollution problems in Guangzhou between 2004 and 2010. (2) The sustainable development ability of the urban ecosystem had been on an up- ward trend in Guangzhou during the study period. The ability of the natural urban ecosystem to support the urban socioeconomic ecosystem increased continuously, and the improved ecoenvironment enhanced the harmony and vitality of the urban ecosystem in Guangzhou.
文摘Wetland ecosystems, particularly the mangrove forest, are the primary wild habitat of heronry birds. However, urban ecosystems have become a favorite breeding habitat of these birds. To provide inputs into the habitat management for conservation of these birds, we investigated the quantitative and qualitative characteristics of nesting trees of heronry birds in the urban environment of the North Kerala region of peninsular India. Census on nesting trees was done in 3 major microhabitats of the urban ecosystem: avenues of national highways and towns, nonresidential plots, and residential areas apart from the mangrove islets in the peri-urban locality. The study found that 174 trees of 22 species hosted 1,928 heronry bird nests in the urban habitats; mangrove forests, although plentiful in the study area, hosted only about 20% of the total nests encountered in the study. Rain trees Samanea saman (43.7%) were the most available nesting tree. The greatest number of nests and nesting trees were encountered on the roads of urban areas, followed by nonresidential areas and residential areas. The differences in the observed frequencies of nesting trees in 3 microhabitats and in 3 types of roads (national highways 〉 state highways 〉 small pocket road) were significant. Canopy spread, girth size, and quality of the trees predicted the tree selection of the heronry birds in urban environments. Therefore, we recommend proper management and notification of the identified nesting trees as protected sites for the conservation of herorny birds.
文摘In the light of the study of domestic and foreign ur-ban ecosystem,this article puts forward a set of ideological systemsfor the forecast,evaluation and tactic,and conducts initial primaryexploration of its forecast and evaluation methods.
基金supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2020237 and 2019234)the National Natural Science Foundation of China(Grant No.42171109 and 32130068).
文摘Urban parks are an important part of urban ecosystems and play an important role in biodiversity conservation.However,it is still unclear how park characteristics aff ect plant diversity which could hinder the conservation of urban biodiversity due to the ineff ective design of urban parks.The diversity of woody plants in 33 parks of Changchun,China,was measured with plot measurements and linked with urban park characteristics(e.g.,size and age of the park)to uncover the relationship between them.The results show that urban woody plant species were abundant,with 98 species belonging to 51 genera and 26 families in the snow climate city of Changchun.The variation in woody plant diversity was largely explained by internal patch characteristics(e.g.,size,age,shape),and external factors surrounding the park(e.g.,land use type and socioeconomic level)accounted for only 16.0%in our study.For internal patch characteristics,older urban parks with larger areas demonstrated a richer level of plant diversity and increased nonlinearly with increasing park area.The threshold size signifi cantly aff ecting plant diversity variation was approximately 30 ha.Plant diversity had positive linear relationships with the ages of urban parks,supporting the legacy eff ect.In addition,woody plant diversity nonlinearly decreased with increasing park shape index,which suggested that the plant diversity could also be increased by optimizing the park shape.Regarding the external factors surrounding parks,the spatial distribution of woody plant diversity varied greatly from the urban center to the suburbs.House prices around the park had positive linear relationships with woody plant diversity in parks,supporting the luxury eff ect.However,building and road proportions,and green space proportion had no relationship with plant diversity in parks.This study can provide a robust reference for enriching plant diversity in urban parks,thus improving the development of urban sustainable cities.
基金Supported by the National Natural Science Foundation of China(No.31770223)the Excellent Achievement Cultivation Project of Higher Education in Shanxi(No.2020KJ029)the Scientifi c and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2019L0778)。
文摘Microorganisms play a key role in aquatic ecosystems.Recent studies show that keystone taxa in microbial community could change the community structure and function.However,most previous studies focus on abundant taxa but neglected low abundant ones.To clarify the seasonal variation of bacterial and microalgal communities and understand their synergistic adaptation to diff erent environmental factors,we studied the bacterial and eukaryotic phytoplankton communities in Fenhe River that runs through Taiyuan City,central China,and their seasonal co-occurrence patterns using 16S and 18S rDNA sequencing.Results indicate that positive interaction of eukaryotic phytoplankton network was more active than negative one except winter,indicating that the cooperation(symbiotic phenomenon in which phytoplankton are interdependent and mutually benefi cial)among them could improve the adaption of microbial community to the local environmental changes and maintain the stability of microbial network.The main genera that identifi ed as keystone taxa in bacterial network were Salinivibrio and Sphingopyxis of Proteobacteria and they could respond to the variation of nitrite and make use of it,while those that identifi ed as keystone taxa in eukaryotic phytoplankton network were Pseudoschroederia and Nannochloris,and they were more susceptible to nitrate and phosphate.Mychonastes and Cryptomonas were closely related to water temperature.However,the loss of the co-occurrence by environmental factor changes aff ected the stability of network structure.This study provided a reference for analyzing relationship between bacteria and eukaryotic phytoplankton and revealing potential importance of keystone taxa in similar ecological domains in carbon,nitrogen,and phosphorus dynamics.
基金Sponsored by Science and Technology Project of Beijing Municipal Administration Center of Parks(ZX2017029)Special Fund for Forest Scientific Research in the Public Welfare(201404301)
文摘Ecosystem services of urban green spaces play an important role in the sustainable development of the urban ecosystem. How to quantify the ecological benefits of urban green spaces and evaluate their ecological services is a hot topic in related fields. Currently, with the advancement of science and technology, the assessment method has been developed from the traditional ones such as the Council of Tree and Landscape Appraisers(CTLA) method, afforestation cost method, and carbon tax method to CITYgreen and i-Tree. The latter two models have been widely used in countries of Europe and America, while the use of i-Tree has not been promoted in China. In this paper, i-Tree Eco(UFORE) was selected for research, and its application in the assessment of the ecosystem services of urban green spaces, including energy saving, air quality improvement, interception of rainwater, and aesthetic benefits, were analyzed. This study aims to provide a theoretical and scientific basis for the introduction and localization of i-Tree, as well as its generalization in the assessment of forest ecosystem services domestically.
基金financially supported by COST Action FP1204 GreenInUrbsPRIN project EUFORICCMinistry of Education and Science of the Russian Federation(the Agreement No.02.A03.21.0008)
文摘As a Nature-Based Solution,urban forests deliver a number of environmental ecosystem services(EESs).To quantify these EESs,well-defined,reliable,quantifiable and stable indicators are needed.With literature analysis and expert knowledge gathered within COST Action FP1204 GreenInUrbs,we proposed a classification of urban forest EESs into three categories:(A)regulation of air,water,soil and climate;(B)provisioning of habitat quality;and(C)provisioning of other goods and services.Each category is divided into EES types:(a)amelioration of air quality;restoration of soil and water;amelioration of the microclimate;removal of CO2 from the air;(b)provision of habitat for biodiversity;support for resilient urban ecosystems;provision of genetic diversity;and(c)provision of energy and nutrients;provision of grey infrastructure resilience.Each EES type provides one or more benefits.For each of these 12 benefits,we propose a set of indicators to be used when analyzing the impacts on the identified EESs.Around half of the 36 indicators are relevant to more than one single benefit,which highlights complex interrelationships.The indicators of wider applicability are tree and stand characteristics,followed by leaf physical traits and tree species composition.This knowledge is needed for the optimization of the EESs delivered by urban forests,now and in the future.
基金supported by the National Natural Science Foundation of China [Grant number 41371176]the Fundamental Research Funds for the Central Universities[Grant number lzujbky_2017_it91]
文摘Urban planning has become a widely concern for minimizing the negative effects of urban expansion on terrestrial ecosystems. We developed an interdisciplinary modeling framework to evaluate the effectiveness and shortcomings of urban expansion management strategies. A three-step method was applied to Yinchuan Plain in the northwestern of China, including(1)analyzing the relationship between landscape pattern and ecosystem service values through mathematical statistics;(2) predicting landscape pattern and ecosystem services change under different scenarios based on cellular automaton model(SLEUTH-3r model); and(3) designing and validating optimized scenario through integrating historical analysis experiments and future multi-comparison suggestions. Results have suggested that landscape composition and configuration can significantly affect regional ecosystem service values, especially the connectivity and shape of landscape. Compact urban growth policy and medium environment protection policy are the appropriate setting for urban expansion plan. Optimization validation of the combined designed scenario implied the reliability of this method. Our results highlighted the significance of integrating application of landscape pattern analysis, ecosystem service value evaluation,model simulation and multi-scenario prediction in urban planning.
基金supported by the 135 Strategic Program of the Institute of Mountain Hazards and Environment, CAS (NO.SDS-135-1703)the Science and Technology Service Network Initiative (No. KFJ-STS-QYZD-060)+2 种基金Doctor Startup Foundation of China West Normal University (N0. 412650)the Sichuan Center for Rural Development Research Project (No. CR1811)Scientific Research Innovation Team Projects of China West Normal University (N0. CXTD2018-10)
文摘China is undergoing a rapid urbanization process,and urbanization will have a direct impact on regional ecosystems and affect regional ecosystem services.Considering the mountainous counties in Southwestern China as the research object,this study reveals the spatial clustering characteristics of four typical ecosystem services(food production,soil conservation,water yield and carbon sequestration)as well as the trade-offs and synergies among ecosystem services in different urbanized areas.At the same time,piecewise linear regression is used to determine the threshold of the influence of urbanization on ecosystem services.The results indicate that:1)There are spatial autocorrelations among the four typical ecosystem services;with strong clustering characteristics,the positive correlation types are"clustered"locally;and with significant spatial heterogeneity,the negative correlation types are scattered and mainly appear in the highly urbanized area.2)There are also remarkable differences in the relationship among various ecosystem services in different urbanized areas,and in particular,there are marked trade-offs between food production and carbon sequestration in the moderately urbanized area and the highly urbanized area.However,there are synergies between them in the lowly urbanized area.3)With an increase in the compounded night light index(CNLI),water yield,carbon sequestration,food production and overall ecosystem services values present an increasing-decreasing trend,the soil conservation function value shows a decreasing-increasing trend.The response of water yield,carbon sequestration,food production,and overall ecosystem services to the compounded night light index(CNLI)has a threshold of 1.2642,1.4833,1.3388,1.5146 and 1.2237,respectively.Based on the detected relationships between urbanization and ecosystem services,this study provides a theoretical reference for the selection of urbanization development models in key ecological functional areas.
文摘The relationship between ecosystem services and urban phytodiversity is being studied in the Moukonzi-Ngouaka district of Brazzaville. Urban forestry, a source of well-being for the inhabitants, is associated with socio-cultural foundations. The surveys concern flora, ethnobotany, socio-economics and personal interviews. The 60.30% naturalized flora is heterogeneous and closely correlated with traditional knowledge. The Guineo-Congolese endemic element groups are 39.27% of the taxa, of which 3.27% are native to Brazzaville. Ethnobotany recognizes 48.36% ornamental taxa;28.36% food taxa;and 35.27% medicinal taxa. Some multiple-use plants are involved in more than one field. The supply service, a food and phytotherapeutic source, provides the vegetative and generative organs. Of the 52.31% of recognized taxa, 33.45% essentially provide leaves and 18.50% fruits. The main obsession of plant introduction being 1) food and phytotherapeutic, and 2) aesthetic, obscures other ecosystem services such as fuelwood and income, provided by NTFPs, pillars of poverty alleviation.
文摘Sustainable urban forest management is still an evolving concept, particularly as it pertains to a sustainable supply of ecosystem benefits and management planning. Urban forestry maintains a greater human dimension component than traditional timber-oriented rural forestry because urban trees grow in city centers and neighborhoods, supplying critical ecosystem benefits to the population centers. The overall goal of this study was to evaluate the relationship of urban forest stand structure and its temporal dynamics with the sustainable supply of ecosystem benefits in university environments. Individual tree data were collected from a completed inventory, while the i-Tree Eco model was used to generate ecosystem benefits data from the Clemson urban forest. The cumulative-benefits supply curve had an inverted J-shaped curve, but the average supply curve had a negative slope against the species richness. Likewise, individual tree variables total height, DBH, leaf area, and crown height strongly correlated with the total ecosystem services supply. Based on the temporal supply trends, the study area trees were broadly segmented into three groups: establishment, growth, and legacy, with 65%, 31%, and 4% frequency distribution, respectively. Urban forest managers need to identify forest management goals and preferred ecosystem benefits among the urban communities to guide the required forest structure and dynamics to ensure a sustainable and functioning urban forest.
文摘During land transformation process in the human history, naturalized plants were introduced to several land use patterns by the different ways of plant itself. Including some naturalized plants that had been contribute to land restoration, many naturalized plants have been invaded to original habitat or landscape for native plants. Once the plants were colonized, they extend their area and population size. Urban developed areas often give an important role of source habitat for naturalized plants and expanding their population size. In recent, this situation is appearing as one of environmental problems about the urban landscape management controlling the naturalized plants that invaded in the developed area and conserving the native vegetation. This paper is focusing on relationships between distribution of habitat of naturalized plants and landscape patch in urban area in Seoul. Gangdong-Gu, one of the administrative areas in Seoul was selected for this study. We examined the recent land use change using LANDSAT TM data and spreading of the representative naturalized plants (Robinia pseudoacacia and Eupatorium rugosum) by Seoul Biotope Mapping Project and field survey in 1999. As a result, these two species were often occurred in the same habitat and distributed in forest edge disturbed by man. Their distribution patterns were related to landscape indices (patch size and shape) in the forest edge.
文摘Colombo is the capital of Sri Lanka and the only wetland city in South Asia under the Ramsar Convention. Crow Island Beach Park and associated coastal area belong to the Colombo urban coastal wetland ecosystems. Crow Island wetland contributes diverse habitats for numerous flora and fauna species. The present study was conducted to assess the status of floral diversity in the Crow Island Beach Park and associated coastal ecosystem during the months of August to October 2021. Study area is divided in to three sites (A, B, C). Line transects method and field observations were used in the study. This coastal wetland consists of mosaic of five major vegetation types: Herbaceous, tree, shrub, creeper, grass and other than that marine algae namely<em> Chaetomorpha antennina</em>, <em>Rhizoclonium africanum</em>, <em>Ulva compressa</em> belonging to chlorophyta (green algae) and <em>Grateloupia</em> <em>lithophila</em> belonging to rhodophyta (red algae) were found in the study area. A total number of 102 flora species belonging to 50 families were recorded from the study area. There were two true mangrove species and 16 mangrove associated species in the study sites. Out of the 102 plant species 46 were recognized and documented as plants with medicinal values. Shannon-Wiener diversity indexes for mangrove and mangrove associated species were recorded as 2.378, 2.304 and 1.676 in site A, B and C respectively. Simpson’s diversity index for mangrove and mangrove associated species was recorded as 0.889, 0.874 and 0.735 respectively in site A, B and C and Jaccard index of similarity between three study sites showed high values ranging from 41% to 69% for mangrove and mangrove associated species.