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1.
Through their semi-natural and agricultural areas, peri-urban regions are pivotal in providing ecosystem services (ES) to city dwellers. To quantify the ES provided by these areas, it is possible to use ES mapping methods: many ES mapping methods rely on land cover maps, but most maps are coarse compared to the peri-urban scale. Nevertheless, readily-available land use data and methods are often used to map ES at such scales, without contextualisation. As a result, such methods may not be able to capture the diversity that is present in the peri-urban vegetation, which could have consequences for their accuracy and furthermore for urban planning policies.To increase our understanding of the applicability of ES mapping methods in peri-urban regions, we assessed to what degree sites with similar plant composition in the green belt of Paris, France, were also projected to have similar ES bundles. We considered two commonly used ES model types: proxy-based models (here: look-up tables) and phenomenological models. We used 252 sites for which botanical survey data were available and applied the ES models to seven ES relevant in the peri-urban context. A cluster analysis was used to group sites, hence facilitating analyse of the spatial congruence between types of vegetation and bundles of ES.Clustering sites based on plant composition revealed six distinct clusters. Clustering sites based on ES bundles as estimated by phenomenological models and proxy-based models, resulted in four and two clusters, respectively. The proxy-based clustering only highlighted broad-leaved forests as an important ES supply source. The phenomenological model estimates of ES allowed a more nuanced clustering of sites into four different groups. The level of congruence between the different sets of clusters based on plant composition and estimated ES bundles was low. Except for forests, the commonly used ES models tested here were not able to represent the same level of heterogeneity in the peri-urban landscape as was found in the vegetation. Our results demonstrate the need to integrate finer scale approaches and primary data in ES assessments of peri-urban areas.  相似文献   

2.
Assessing mismatches between ecosystem service (ES) supply and demand can provide relevant insights for enhancing human well-being in urban areas. This paper provides a novel methodological approach to assess regulating ES mismatches on the basis of environmental quality standards and policy goals. Environmental quality standards (EQS) indicate the relationship between environmental quality and human well-being. Thus, they can be used as a common minimum threshold value to determine whether the difference between ES supply and demand is problematic for human well-being. The methodological approach includes three main steps: (1) selection of EQS, (2) definition and quantification of ES supply and demand indicators, and (3) identification and assessment of ES mismatches on the basis of EQS considering certain additional criteria. While ES supply indicators estimate the flow of an ES actually used or delivered, ES demand indicators express the amount of regulation needed in relation to the standard. The approach is applied to a case study consisting of five European cities: Barcelona, Berlin, Stockholm, Rotterdam and Salzburg, considering three regulating ES which are relevant in urban areas: air purification, global climate regulation and urban temperature regulation. The results show that levels of ES supply and demand are highly heterogeneous across the five studied cities and across the EQS considered. The assessment shows that ES supply contributes very moderately in relation to the compliance with the EQS in most part of the identified mismatches. Therefore, this research suggests that regulating ES supplied by urban green infrastructure are expected to play only a minor or complementary role to other urban policies intended to abate air pollution and greenhouse gas emissions at the city scale. The approach has revealed to be appropriate for the regulating ES air purification and global climate regulation, for which well-established standards or targets are available at the city level. Yet, its applicability to the ES urban temperature regulation has proved more problematic due to scale and user dependent constraints.  相似文献   

3.
We present at a national-scale estimates of spatial covariance between areas important for ecosystem services (ES) and biodiversity, at a fixed spatial scale in France. We calculated different diversity and community metrics for common bird communities: taxonomic diversity (TD), functional diversity (FD), community specialization index (CSI), trophic index (TI), phylogenetic diversity (PD) and community evolutionary distinctiveness (CED). The ES multifunctionality (ESMF) was measured using a combination of ES evenness and overall ES estimator. Spatially explicit tests were used to compare the spatial patterns of ES and diversity metrics. Mixed models were used for comparisons.We found low spatial congruence between ES and both diversity and community metrics in France. However, we detected even opposite associations between ES and each biodiversity component. Crop production was negatively associated with CED, it was positively correlated with CSI. No positive associations were found between ESMF and any diversity metric, independently of farming systems. The only significant association was negative: lower values of CED were associated with hotspots of ESMF. We found also a negative effect of crop production on bird CED. The conservation implication is remarkable, because conservation policies focusing solely on the economic value of ES will fail to protect overall biodiversity.  相似文献   

4.
The use of Ecosystem Services (ES) indicators can help designing, implementing and monitoring public environmental policies. Such indicators may be used as a support tool for natural resources management, like in forest areas, which are important ES providers. In this context, military areas are particularly challenging due to the nature of the activities conducted and the need to conciliate them with ecological protection, without undermining military readiness. It is argued that in addition to technical issues, considering stakeholders’ opinions is beneficial for the selection and design of ES indicators. The main aim of this research is to develop forest ES indicators supported by a participatory indicator selection process. A case study is made of an Atlantic Forest area in the Northeast of Brazil, under the jurisdiction of the Brazilian Army. To accomplish that aim, a questionnaire survey was sent to a group of stakeholders in order to evaluate an initial set of proposed 44 indicators for several forest ES. Through a weighting of stakeholders’ scores, 25 ES indicators for the Atlantic forest were obtained. The selected indicators portray the study area mainly as a provider of regulating, cultural and habitat services and less of provisioning services, which can be related with military and nature protection restrictions on the use of provisioning ES. Nevertheless, the three top-rated indicators dealt with water availability, regulation and quality (for human consumption). Together with the predominance of water-related ES that was observed (ten out of 25 indicators), this points out the relevance of forest water-related ES in the study area. On the other hand, the specificity of the military context was not clearly reflected by the indicators selected, since most of them are applicable in areas or contexts other than a military one. Alongside indicators expressing the benefits provided by nature, stakeholders’ scorings reveal recognition of the importance of biodiversity and resilience of the area. This stresses the importance of biodiversity and resilience to support ES supply, but is also linked with one of the major challenges for managing a military area with high natural value: that of conciliating military activities (that support military readiness) with nature protection. Other forest areas under military or similar particular jurisdiction, often representing a major fraction of national forests, could learn from this approach and identify areas for priority response measures. These indicators could be also a driver to increase and improve environmental management of military training activities and safeguarding natural resources in important ES providing areas like Atlantic forests.  相似文献   

5.
The rapid decline in urban green (UGS) and blue space (UBS) in developing countries has led to a widespread degradation of available ecosystem services (ES). However, impacts of UGS and UBS changes on ES tend to vary over space and time, and to date these impacts have not been studied in sufficient detail in emerging economies. By comparing UGS and UBS change patterns with multitemporal Landsat data recorded during the past 30 years (1991–2021), this study has examined the impact of several factors on ES in some of the world's climate hotspots. Although obtaining relevant and accurate information on ES is difficult in many parts of the developing world, this work has developed baseline data suitable for assessing ES loss over five densely populated cities in Bangladesh – Dhaka, Chattogram, Khulna, Rajshahi, and Sylhet. ES loss was quantified in monetary terms using adjusted value coefficients. The topographic and anthropogenic factors driving spatial differences in ES degradation in these cities were analyzed with a geographical detector. The results indicated that the cities experienced a combined monetary loss of USD 628.58 million as a result of specific ES degradation, primarily due to the decline of UGS and UBS. The value of ES loss was notably higher in Dhaka and Chattogram than in the other cities due to marked differences in anthropogenic activities. Population growth, extensive urban sprawl, and the development of dense road networks were identified as the major causes of urban green and blue space loss and consequent reduction of ES. The findings of this study provide important insights which can be used to support the formulation of public policies and management plans aimed at restoring and maintaining sustainable urban ecosystems.  相似文献   

6.
This study investigates how the ecosystem services (ES) linked to livestock grazing are perceived across countries. A total of 82 case studies collected from 42 countries via survey (53.7% cases from Europe and 46.3% from outside of Europe) have been analysed through a multivariate approach. In all, 18 non-provisioning ES were considered. Overall, the reported impacts of livestock grazing on the different ES were much more positive than negative. Notably, a large proportion of respondents reported either positive or very positive impacts for some cultural ES, namely cultural, historic and natural heritage (84%), knowledge systems and educational values (77%), landscape values (74%), and for some supporting and regulating ES, namely habitat provision (66%), nutrient cycling (65%), and bush encroachment/fire control (66%). Based on multiple regression analysis, geographic origin, stakeholder type and species category, as well as protection status of the grazing area, had significant effects on the perception of the impacts. Respondents reported those impacts as more positive in Europe, in protected areas and where several species were present in the grazing area. A significantly larger proportion of respondents reported recognition of ES provided by the grazing livestock population in European countries (40.9%) compared with non-European countries (23.7%). Based on the survey responses it appears that in non-European countries absence of formal recognition, especially by policy makers, is a major challenge for the continued provision of ES in grazing systems. In Europe, where such recognition is already often included in legislation, the long-term sustainability of related policies and incentives to provide such services is viewed as a major issue by the respondents.  相似文献   

7.
We analyze the evolutionary consequences of host resistance (the ability to decrease the probability of being infected by parasites) for the evolution of parasite virulence (the deleterious effect of a parasite on its host). When only single infections occur, host resistance does not affect the evolution of parasite virulence. However, when superinfections occur, resistance tends to decrease the evolutionarily stable (ES) level of parasite virulence. We first study a simple model in which the host does not coevolve with the parasite (i.e., the frequency of resistant hosts is independent of the parasite). We show that a higher proportion of resistant host decreases the ES level of parasite virulence. Higher levels of the efficiency of host resistance, however, do not always decrease the ES parasite virulence. The implications of these results for virulence management (evolutionary consequences of public health policies) are discussed. Second, we analyze the case where host resistance is allowed to coevolve with parasite virulence using the classical gene-for-gene (GFG) model of host-parasite interaction. It is shown that GFG coevolution leads to lower parasite virulence (in comparison with a fully susceptible host population). The model clarifies and relates the different components of the cost of parasitism: infectivity (ability to infect the host) and virulence (deleterious effect) in an evolutionary perspective.  相似文献   

8.
Conversion of tropical forests is among the primary causes of global environmental change. The loss of their important environmental services has prompted calls to integrate ecosystem services (ES) in addition to socio‐economic objectives in decision‐making. To test the effect of accounting for both ES and socio‐economic objectives in land‐use decisions, we develop a new dynamic approach to model deforestation scenarios for tropical mountain forests. We integrate multi‐objective optimization of land allocation with an innovative approach to consider uncertainty spaces for each objective. These uncertainty spaces account for potential variability among decision‐makers, who may have different expectations about the future. When optimizing only socio‐economic objectives, the model continues the past trend in deforestation (1975–2015) in the projected land‐use allocation (2015–2070). Based on indicators for biomass production, carbon storage, climate and water regulation, and soil quality, we show that considering multiple ES in addition to the socio‐economic objectives has heterogeneous effects on land‐use allocation. It saves some natural forest if the natural forest share is below 38%, and can stop deforestation once the natural forest share drops below 10%. For landscapes with high shares of forest (38%–80% in our study), accounting for multiple ES under high uncertainty of their indicators may, however, accelerate deforestation. For such multifunctional landscapes, two main effects prevail: (a) accelerated expansion of diversified non‐natural areas to elevate the levels of the indicators and (b) increased landscape diversification to maintain multiple ES, reducing the proportion of natural forest. Only when accounting for vascular plant species richness as an explicit objective in the optimization, deforestation was consistently reduced. Aiming for multifunctional landscapes may therefore conflict with the aim of reducing deforestation, which we can quantify here for the first time. Our findings are relevant for identifying types of landscapes where this conflict may arise and to better align respective policies.  相似文献   

9.
Endosidin20 (ES20) is a recently identified cellulose biosynthesis inhibitor (CBI) that targets the catalytic site of plant cellulose synthase (CESA). Here, we screened over 600 ES20 analogs and identified nine active analogs named ES20-1 to ES20-9. Among these, endosidin20-1 (ES20-1) had stronger inhibitory effects on plant growth and cellulose biosynthesis than ES20. At the biochemical level, we demonstrated that ES20-1, like ES20, directly interacts with CESA6. At the cellular level, this molecule, like ES20, induced the accumulation of cellulose synthase complexes at the Golgi apparatus and inhibited their secretion to the plasma membrane. Like ES20, ES20-1 likely targets the catalytic site of CESA. However, through molecular docking analysis using a modeled structure of full-length CESA6, we found that both ES20 and ES20-1 might have another target site at the transmembrane regions of CESA6. Besides ES20, other CBIs such as isoxaben, C17, and flupoxam are widely used tools to dissect the mechanism of cellulose biosynthesis and are also valuable resources for the development of herbicides. Here, based on mutant genetic analysis and molecular docking analysis, we have identified the potential target sites of these CBIs on a modeled CESA structure. Some bacteria also produce cellulose, and both ES20 and ES20-1 inhibited bacterial cellulose biosynthesis. Therefore, we conclude that ES20-1 is a more potent analog of ES20 that inhibits intrinsic cellulose biosynthesis in plants, and both ES20 and ES20-1 show an inhibitory effect on bacterial growth and cellulose synthesis, making them excellent tools for exploring the mechanisms of cellulose biosynthesis across kingdoms.  相似文献   

10.
A useful approach for exploring gene function involves generating mutant mice from genetically modified embryonic stem (ES) cells. Recent advances in genetic engineering of ES cells have shifted the bottleneck in this process to the generation of mice. Conventional injections of ES cells into blastocyst hosts produce F0 generation chimeras that are only partially derived from ES cells, requiring additional breeding to obtain mutant mice that can be phenotyped. The tetraploid complementation approach directly yields mice that are almost entirely derived from ES cells, but it is inefficient, works only with certain hybrid ES cell lines and suffers from nonspecific lethality and abnormalities, complicating phenotypic analyses. Here we show that laser-assisted injection of either inbred or hybrid ES cells into eight cell-stage embryos efficiently yields F0 generation mice that are fully ES cell-derived and healthy, exhibit 100% germline transmission and allow immediate phenotypic analysis, greatly accelerating gene function assignment.  相似文献   

11.
This paper contributes to the discussion on integrating societal considerations, stakeholders' perceptions and laymen knowledge into ecosystem services (ES) assessments. The paper illustrates how social mapping of perceived ES supply (or alternatively demand) can contribute to integrated ES assessment. Based on sketched locations of the, according to 38 respondents, most important ES at the local scale, we describe the perceived ES distribution with social landscape metrics (abundance, diversity, richness, risk, rarity) based on traditional landscape ecology indicators. We illustrate how social landscape metrics can inform ES management and planning and describe how synergies between ES as stated by the respondents differ from calculated synergies (the latter based on correlation coefficients between perceived ES abundance). We present indicators pointing to locations where (multiple) ES synergies are perceived by stakeholders (stated synergy index), and to conflicting ES and ES perceived to be at risk (risk index). Overlapping social ES hotspots based on the social landscape metrics with ES hotspots based on more traditional biophysical modelling (biophysical hotspots) and ecological inventories (ecological hotspots) results in social–ecological or social–biophysical hotspots, coldspots and warmspots relevant for nature and landscape planning, management and governance. Based on an analysis of the overlaps between social, biophysical and ecological hotspots on the one hand, and the contribution of ecological quality, land zoning categories and conservation statuses on the other hand, we discuss the added value of integrating social ES mapping in integrated ES assessment, above ES assessments based on biophysical or ecological attributes. Given the limited overlap between social hotspots and ecological or biophysical hotspots, we conclude that integrating stakeholders' mapping of perceived ES supply (or demand) into ES assessments is necessary to reflect the societal aspects of ES in ES assessments. However, with a limited sample of respondents, there is a risk of collectivisation of respondents' viewpoints as a common, societal stance. Moreover, the social landscape metrics are not suitable for describing the distribution of ES with low perceived abundance. Finally, we explain how social ES assessment can result in mainstreaming ES in planning, policy and practice.  相似文献   

12.
Chimeric or entirely embryonic stem (ES) cell-derived mice ("ES mice") can be produced by injecting ES cells into diploid (2n) or tetraploid (4n) host blastocysts, respectively. Usually, between 10 and 15 ES cells are injected into the host blastocyst, but it is not clear how many of the injected cells contribute to the somatic lineages, thus serve as "founder cells" of the embryo proper. We have used genetically labeled ES cells to retrospectively determine the number of founder ES cells that generate the somatic lineages of chimeric and of ES mice. ES cell clones individually labeled with provirus were mixed in equal numbers and injected into 2n or 4n blastocysts to generate chimeric or ES mice. Southern analysis of DNA from the resulting animals indicated that the somatic lineages were most often derived from one or two and sometimes from up to three founder ES cells. The number of founder cells was independent of the total number of cells injected into the host blastocysts. Our results are consistent with the notion that constraints of the host embryo restrict the number of ES cells that can contribute to a chimeric or an ES mouse.  相似文献   

13.
14.
鱼类的胚胎干细胞   总被引:6,自引:1,他引:6  
胚胎干细胞(ES)是未分化的细胞培养物,来自动物的早期胚胎。它们能成为稳定的细胞系和长期冻存。在适当的条件下,ES细胞能分化成各种细胞类型,包括生殖细胞。这样,ES细胞就提供了一个有效的纽带,将动物基因组的体外和体内遗传操作连系起来。ES细胞的魅力就由其在产生和分析基因敲除老鼠中显现出来。目前,ES细胞技术仅见之老鼠,因其它脊椎动物的ES细胞的培养和建系难获成功。在鱼类,人们已做了大量的尝试。我们以青鳉(Oryzias latipes)作为建立鱼类ES细胞技术的模式,通过建立并应用无滋养层细胞的培养条件,获得了来自中期囊胚的ES细胞系。青鳉的ES细胞和老鼠的ES细胞有很多共同特征,如二倍体核型、分化潜力和形成嵌合体。因此,在鱼类建立和应用ES细胞技术是可能的。青鳉ES细胞的培养条件已成功地应用到其它鱼类如斑马鱼甚至海水鱼。本文旨在以青鳉为模式,综述获得和应用模式鱼和经济鱼ES细胞的主要进展和前景。  相似文献   

15.
Extracellular signal-regulated kinases (ERKs) have been implicated to be dispensable for self-renewal of mouse embryonic stem (ES) cells, and simultaneous inhibition of both ERK signaling and glycogen synthase kinase 3 (GSK3) not only allows mouse ES cells to self-renew independent of extracellular stimuli but also enables more efficient derivation of naïve ES cells from mouse and rat strains. Interestingly, some ERKs stay active in mouse ES cells which are maintained in regular medium containing leukemia inhibitory factor (LIF) and bone morphogenetic protein (BMP). Yet, the upstream signaling for ERK activation and their roles in mouse ES cells, other than promoting or priming differentiation, have not been determined. Here we found that mouse ES cells express three forms of Raf kinases, A-Raf, B-Raf, and C-Raf. Knocking-down each single Raf member failed to affect the sustained ERK activity, neither did A-Raf and B-Raf double knockdown or B-Raf and C-Raf double knockdown change it in ES cells. Interestingly, B-Raf and C-Raf double knockdown, not A-Raf and B-Raf knockdown, inhibited the maximal ERK activation induced by LIF, concomitant with the slower growth of ES cells. On the other hand, A-Raf, B-Raf, and C-Raf triple knockdown markedly inhibited both the maximal and sustained ERK activity in ES cells. Moreover, Raf triple knockdown, similar to the treatment of U-0126, an MEK inhibitor, significantly inhibited the survival and proliferation of ES cells, thereby compromising the colony propagation of mouse ES cells. In summary, our data demonstrate that all three Raf members are required for ERK activation in mouse ES cells and are involved in growth and survival of mouse ES cells.  相似文献   

16.
The endolymphatic sac (ES) is an organ that is located in the temporal bone. Its anatomical location makes ES tissue collection without any contamination very difficult, and sometimes accurate molecular analyses of the ES are prevented due to this matter. In the present study, a new selective ES epithelial tissue collection method was attempted using laser capture microdissection to obtain pure ES RNA without any contamination. The validity of this method was demonstrated by RT-PCR with three specific primer pairs against osteocalcin, calponin H1, and NKCC2, which are specific proteins in bone, smooth muscle, and kidney/ES cells, respectively. From the RT-PCR results, the high specificity and sufficient sensitivity of the new method was indicated. It is considered that the new method is optimal for ES collection without contamination and it will be able to contribute to future analyses of the ES.  相似文献   

17.
18.
Tetraploid (4n) embryo complementation assay has shown that embryonic stem (ES) cells alone are capable of supporting embryonic development (ES mouse), allowing the recovery of mouse lines directly from cultured ES cell lines. Although the advantages of this technique are well recognized, it remains inefficient for generating ES mice. In the present study, we investigated the effects of cell number of host 4n embryos on the production of ES mice. Four independent ES cell lines (two general ES cell lines and two nuclear transfer-derived ES cell lines) were used, and each cell line was aggregated with single (1x) to triple (3x) host 4n embryos. We found that birth rate of ES mice using 1x 4n embryos was quite low (0-2%) regardless of cell line, whereas except for one cell line, approximately 6-14% of embryos developed to full term in the case of 3x 4n embryos. Contamination of host 4n cells in ES mice was quite rare, being comparable to that generated using general methods even if they were delivered from 3x 4n host embryos. These results demonstrate that the use of 3x 4n embryos is effective for generating ES mice. Our technique described here will be applicable to any ES cell line, including general ES cell lines used for gene targeting.  相似文献   

19.
胚胎干细胞   总被引:4,自引:0,他引:4  
李凌松  王莉 《生命科学》2006,18(4):318-322
胚胎干细胞具有自我复制并分化为人体各种功能细胞的潜能。胚胎干细胞具有的独特生物学特性使其被广泛应用于生物学研究的各个领域,特别是发育学。同时,它潜在的医学应用也成为世界范围内的研究热点。但是,由于人胚胎干细胞的来源为植入前的早期胚胎,人胚胎干细胞自诞生之日起便倍受争议。本文将从胚胎干细胞的来源、特性、鉴定标准、增殖机理、应用前景以及研究本身涉及的伦理学争论给予概述。  相似文献   

20.
Accumulation of mutations in embryonic stem (ES) cells would be detrimental to an embryo derived from these cells, and would adversely affect multiple organ systems and tissue types. ES cells have evolved multiple mechanisms to preserve genomic integrity that extend beyond those found in differentiated cell types. The present study queried whether mismatch repair (MMR) and base-excision repair (BER) may play a role in the maintenance of murine ES cell genomes. The MMR proteins Msh2 and Msh6 are highly elevated in mouse ES cells compared with mouse embryo fibroblasts (MEFs), as are Pms2 and Mlh1, albeit to a lesser extent. Cells transfected with an MMR reporter plasmid showed that MMR repair capacity is low in MEFs, but highly active in wildtype ES cells. As expected, an ES cell line defective in MMR was several-fold less effective in repair level than wildtype ES cells. Like proteins that participate in MMR, the level of proteins involved in BER was elevated in ES cells compared with MEFs. When BER activity was examined biochemically using a uracil-containing oligonucleotide template, repair activity was higher in ES cells compared with MEFs. The data are consistent with the suggestion that ES cells have multiple mechanisms, including highly active MMR and BER that preserve genetic integrity and minimize the accumulation of mutations.  相似文献   

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