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1.
Throughout the development sector, there is increasing recognition of links between the environment and aspects of development such as poverty alleviation, health, income generation, and agriculture. While furnished with a diverse range of perspectives and approaches, development practice is in need of ways to better conceptualize the interactions between the social, environmental, and economic dimensions of sustainability so that opportunities for simultaneous improvement in human and ecological well-being can be identified more readily. Critical systems thinking is proposed as a way for development practitioners to conceptualize and act toward the integration of these economic, social, and environmental dimensions and, in so doing, support communities to nurture both human and ecosystem well-being. Four desirable attributes of a critical systems thinking approach to development are identified based on development literature, critical systems literature, and the author’s research into sustainability in semi-rural communities in Vietnam. The four attributes are ‘a systems thinking approach;’ ‘an ethical base to action and choices;’ ‘critical reflection permeates processes;’ and ‘appreciation of diverse views and application of diverse approaches.’ These attributes are described and then offered as the basis for further discussion of the ways in which simultaneous improvement of human well-being and ecosystem health can become an integral part of development practice.  相似文献   

2.
In spite of the consideration that toxicity testing is a reduced approach to measure the effects of pollutants on ecosystems, the early-life-stage (ELS) tests have evident ecological relevance because they reflect the possible reproductive impairment of the natural populations. The procedure and validation of Crassostrea rhizophorae embryonic development test have shown that it meets the same precision as other U.S. EPA tests, where EC(50) is generally used as a toxicological endpoint. However, the recognition that EC(50) is not the best endpoint to assess contaminant effects led U.S. EPA to recently suggest EC(25) as an alternative to estimate xenobiotic effects for pollution prevention. To provide reliability to the toxicological test results on C. rhizophorae embryos, the present work aimed to establish the critical effect level for this test organism, based on its reaction to reference toxicants, by using the statistical method proposed by Norberg-King (Inhibition Concentration, version 2.0). Oyster embryos were exposed to graded series of reference toxicants (ZnSO(4) x 7H(2)O; AgNO(3); KCl; CdCl(2)H(2)O; phenol, 4-chlorophenol and dodecyl sodium sulphate). Based on the obtained results, the critical value for C. rhizophorae embryonic development test was estimated as EC(15). The present research enhances the emerging consensus that ELS tests data would be adequate for estimating the chronic safe concentrations of pollutants in the receiving waters. Based on recommended criteria and on the results of the present research, zinc sulphate and 4-chlorophenol have been pointed out, among the inorganic and organic compounds tested, as the best reference toxicants for C. rhizophorae ELS-test.  相似文献   

3.
Studies on toxicities and tolerances of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) in the brown alga Isochrysis galbana and in the green-lipped mussel Perna viridis were conducted by short-term bioassays using endpoints growth production and mortality, respectively. The 5-day EC(50) and 24-h LC(50) of these heavy metals were determined in the brown alga and mussel, respectively. The EC(50) values calculated for the alga were 0.74 mg/l for Cd, 0.91 mg/l for Cu, 1.40 mg/l for Pb and 0.60 mg/l for Zn. The LC(50) values for the mussels were 1.53 mg/l for Cd, 0.25 mg/l for Cu, 4.12 mg/l for Pb and 3.20 mg/l for Zn. These LC(50) values were within the concentration ranges as reported by other authors who used P. viridis as the test organism. Based on these EC(50) and LC(50) values, the alga was most sensitive to Zn, followed by Cd, Cu and Pb while the mussel was most sensitive to Cu, followed by Cd, Zn and Pb. Differences in the trophic levels, metal handling strategies, biology and ecology of the primary producer (brown alga) and the primary consumer (mussel) are believed to be the plausible causes for the different toxicities and tolerances of the metals studied.  相似文献   

4.
Social-ecological traps are theorized to be present when human actions affect feedbacks and drivers in social-ecological systems, which, in turn, lead to regime shifts that may alter ecosystem capacity to generate services on which human wellbeing depends, and this, in turn, triggers societal responses, where actors and institutions interact with ecological dynamics and unwittingly lock development into a vulnerable pathway. The key dynamic in this theorization seems to be that human action often predicates or initiates the series of cascading affects that determine the presence of, and, perhaps, the effectiveness of, social-ecological traps. However, what drives human action in this context? What logic, assumptions, decisions, world views, and other processes are implicated in this configuration? This paper first briefly reviews ecological identity and the problems of anthropocentricism, human exceptionalism, and human exemptionalism and introduces the term ecological disenfranchisement. Building upon this, the author invokes Horn’s logic and dialectical traps as a lens for understanding human roles and the prevalence of issues with ecological identities, within social ecological traps. Drilling further down, the paper illustrates these traps with short vignettes, in each case, attempting to link the human logical traps with larger system dynamics. Finally, the author proposes a chain of reasoning to serve as an example of how the presence of human logic traps (or entrapment) in a number of different spheres has an impact upon the larger system, and, perhaps, even predicts entrapment of the larger system. Future efforts to either understand social-ecological traps or navigate away or out of them must first take stock of the human logical traps that actors within the systems are influenced by, and that influence the large system(s).This paper argues that failing to account for human traps within will render most efforts to avoid or escape social-ecological traps futile.  相似文献   

5.
Food ecologies and economies are vital to the survival of communities, non-human species, and our planet. While environmental communication scholars have legitimated food as a topic of inquiry, the entangled ecological, cultural, economic, racial, colonial, and alimentary relations that sustain food systems demand greater attention. In this essay, we review literature within and beyond environmental communication, charting the landscape of critical food work in our field. We then illustrate how environmental justice commitments can invigorate interdisciplinary food systems-focused communication scholarship articulating issues of, and critical responses to, injustice and inequity across the food chain. We stake an agenda for food systems communication by mapping three orientations—food system reform, justice, and sovereignty—that can assist in our critical engagements with and interventions into the food system. Ultimately, we entreat environmental communication scholars to attend to the bends, textures, and confluences of these orientations so that we may deepen our future food-related inquiries.  相似文献   

6.
This study examines what happens when contentious lay citizens harness the technical-ecological repertoire of experts as means of challenging nature conservation policy. The causes, manifestations, and implications of this phenomenon are elucidated through a critical discourse analysis. The case study is based on the wolf reintroduction project in Europe, with particular focus on Sweden, using illegal hunting discussions as a point of entry within the hunting community. It reveals the deployment of three topoi, which are defined as stock arguments situated within a discourse. Analysis shows how while some topoi often incur short-term gains in the debate because of their scientific guise, they are fundamentally relegated as folk science (or “barstool biology”) by government experts and, in some cases, contribute to the further marginalization of other knowledges. Acquiescence to this discourse is shown to greatly impede the debate. Finally, the study shows how lack of trust in the public dialog, which hunters openly recognize to be colonized by ecological expertise, results in increasingly noncommunicative forms of resistance toward policy.  相似文献   

7.
Glutaraldehyde (GA), an aliphatic dialdehyde disinfectant, and surfactants, one of the major components of detergents, are widely used in hospitals in order to eliminate pathogenic organisms causing nosocomial infectious diseases. After their use, disinfectants and surfactants reach the wastewater network together. The discharge of chemical compounds from hospital activities into wastewater is also a well-known problem, causing pollution of water resources and constituting an ecological risk for aquatic organisms. In this study, the chemistry and toxicology of GA and surfactant mixtures were reviewed in order to estimate their fate in aquatic ecosystems. Furthermore, their joint effects on aquatic organisms were experimentally assessed in the laboratory. A simple model of the additive joint action of toxicants was used to determine combined acute toxicity effects on the bacteria luminescence and Daphnia mobility of three mixtures containing GA at 1.5 x EC50 24 h [in mg/L] on Daphnia and anionic, cationic and nonionic surfactants at twice their critical micellar concentration (CMC). The mixture of GA and a cationic surfactant gave an EC50 30 min on Vibrio fischeri of 0.158%, with a concentration of 0.04 mg GA/L and 1.04 mg CTAB/L, which provided an additive action. The interaction between GA and an anionic surfactant on V. fischeri produced an antagonistic joint action with an EC50 30 min of 3.95%, containing 1.06 mg GA/L and 33.2 mg SDS/L. A synergistic action with an EC50 30 min of 8.4% on V. fischeri was observed for the mixture containing GA and a nonionic surfactant. Antagonistic interactions were observed for the joint action between GA and the surfactants studied on Daphnia. The mixture of GA and CTAB was more toxic (EC50 24 h=0.02%) than the two other mixtures (EC50 24 h GA+SDS=6%; EC50 24 h GA+TX 100=10%). This study provides new data on the toxicity of certain hospital pollutants entering the aquatic environment and detected in surface and groundwaters. It is necessary to study the joint effects of GA and surfactant mixtures following chronic and sublethal standard bioassays in order to estimate the contribution of the additive joint action models in assessing the environmental risk of hospital wastewater (HW).  相似文献   

8.
This article deals with how nature is articulated in public discourse and more specifically how humans’ relationship to nature is constructed via such articulations. Based on critical cultural analyses of ads presented in a Norwegian context, the article claims articulations of nature serve to a depoliticization of nature, which silence social differences and reduce environmental politics to individual moral action. Several rhetorical patterns of particular relevance to the articulation of nature are discussed, pointing out how disparate, sometimes conflicting, understandings of nature are rhetorically configured and aligned in ways that benefit a global market economy. There is a discursive distancing of nature and everyday life, even as nature remains valorized and very much central to national identity. This constrains citizens’ political engagement and undermines understandings of how to govern nature.  相似文献   

9.
The Chernobyl accident led to a long-term crisis that affected agriculture, food and living conditions in complex ways, and that modified the usual economical, political and social relations between public and private stakeholders at local, national and international level. The EC FARMING project aims to create a European stakeholder network to consider possible rehabilitation strategies for rural areas contaminated after a nuclear accident. The Institute of Patrimonial Strategies of the National Institute on Agronomy had responsibility for setting up the French stakeholder group. The objective was to develop favourable conditions and ways whereby stakeholders could deal with such a complex situation as a nuclear emergency and develop rehabilitation strategies. The results from the 3-year work programme on both strategic and technical aspects, showed an increasing commitment from the stakeholders that led to the building up of a common understanding of what a nuclear accident could be and how it could be dealt with.  相似文献   

10.
湖北省洪湖市生态足迹与水足迹动态分析   总被引:2,自引:0,他引:2  
为了分析洪湖市的可持续发展情况,本文运用生态足迹法计算了洪湖市2000~2007年的生态足迹和生态承载力,同时基于生态足迹理论,运用水足迹模型,计算了洪湖市的水足迹.结果表明,洪湖市的人均生态足迹呈整体上升趋势,由1.450 8hm2攀升到2.022 3 hm2,8年间增长近40%,其中能源用地和耕地生态足迹的贡献率最大;人均生态承载力变化不大,稍有下降趋势.2000-2007年洪湖市均表现为生态赤字,且随着生态足迹的不断增大,生态赤字逐渐加大,2007年人均生态赤字达1.373 hm2,表明生产、生活强度已超过生态系统的承载能力,区域生态系统处于人类的过度开发利用和压力之下,洪湖市处于不可持续发展状态.8年间洪湖市水足迹变化不大,2007年为1 399 m3/a,高于全国平均水平,在国内属于水资源丰富型城市.  相似文献   

11.
The current state of the ecology of the impact regions is outlined. It is argued that the complex of ecosystems situated around a point polluter (an impact region) is an appropriate model for solving several fundamental and applied ecological problems related to the exploration of strong external impacts on biota. Typical methodological errors resulting from insufficient attention to specific features of passive experiments are analysed, and ways to avoid them are proposed. The principles of spatial arrangements of study sites within the impact region and of the selection of experimental and evaluation units are discussed.  相似文献   

12.
Shantou, China, is one of the endemic regions of esophageal cancer (EC) in the coastal areas, but the relationship between the multiple exposures of total N-nitroso compounds (TNOCs) and the high risk of EC to date is unclear. This study is to estimate the potential integrative role of multiple exposures of environmental and endogenous TNOC on the EC risk. We collected randomly the samples of 72 h diet and 24 h urine from 256 healthy male (aged 30-65 years) in the high- and low-risk area for EC, and determined the contents of TNOC and 4 N-nitrosamino acids (NAAs) by a method of chemical fission-Thermal Energy Analyzer (TEA) and gas chromatography--TEA, respectively. We used TNOC and NAAs index to evaluate the integrative effect of multiple TNOC exposures on the EC risk by a logistic model. TNOC intake and urinary TNOC content were higher in the high-risk subjects than that in the low-risk subjects by 1.60 micromol/day and 1.45 micromol/L, respectively. TNOC intake, urinary TNOC content and its interaction were significant factors involved in the higher risk of EC (R(2)=0.685, p=0.000) with predicted Correct Class of 85.6%. The risk of the occurrence of a larger SMR of EC may increase by 4.841-fold for every 1 micromol/day increase in TNOC intake (95% CI 2.370-9.888, p=0.000) and by 4.113-fold for every 1 micromol/L increase in urinary TNOC content (95% CI 2.108-8.023, p=0.000), respectively. The integrally role of multiple exposures of TNOC in environment and in vivo may increase the risk of EC in the coastal areas in eastern Guangdong, China.  相似文献   

13.
The objective of this ecological study was to discover associations between selected climate variables and esophageal cancer (EC) mortality in China using a Geographic Information System (GIS). A digital distribution map of EC mortality in China was established in GIS, which was based on one-tenth of nationwide population cause-of-death surveys conducted in mainland China in 1990-1992. Selected climate variables such as 30-year annual average precipitation and evaporation data of the sample areas were extracted from the environmental databases by zonal statistics finished in Spatial Analyst module of ArcInfo 9.0. Drought Indexes were calculated by using the precipitation and evaporation data and a digital distribution map of them was created to compare with the distribution of EC mortality. Correlation and regression analyses were applied to evaluate associations between the EC mortality rates defined at the sample areas and selected climate variables from the raster datasets. The results of the digital GIS maps of EC mortality and Drought Index show that the high EC mortality mostly occurred in areas with high Drought Index. Correlation and regression analyses also show weak negative correlation between precipitation and EC mortality (p<0.001), and weak positive correlation between Drought Index and EC mortality (p<0.001). This study presented a unique model for the link of cancer and climate using a GIS. The study suggests that drought plays a role in the occurrence and development of EC in China, however, other environmental, biological and genetic factors should not be ignored. There is need for further studies using multiple factors and more accurate and detailed environmental and health data.  相似文献   

14.
Conservation discourses tend to portray invasive species as biological entities temporally connected to colonial timelines, using terms such as “alien”, “colonizing”, “colonial”, and “native”. This focus on a colonial timeline emerges from scientific publications within conservation biology and invasion ecology and is enacted through invasive species management by state and NGO actors. Colonialism is influential for indigenous nations in myriad ways, but in what ways do indigenous understandings of invasive species engage with colonialism? We conducted ethnographic research with indigenous Anishnaabe communities to learn about the ways Anishnaabe people conceptualize invasive species as a phenomenon in the world and were gifted with three primary insights. First, Anishnaabe regard plants, like all beings, as persons that assemble into nations more so than “species”. The arrival of new plant nations is viewed by some Anishnaabe as a natural form of migration. The second insight highlights the importance of actively discovering the purpose of new species, sometimes with the assistance of animal teachers. Lastly, while Anishnaabe describe invasive species as phenomenologically entangled with colonialism, the multiple ways Anishnaabe people think about invasive species provide alternatives to native–non-native binaries that dominate much of the scientific discourse.  相似文献   

15.
This study ethnographically identifies and examines a common-sense performer metaphor entangled within deep-rooted Western ecocultural conceptions, in which humans are perceived as separate from and audience to a spectacular nature. I illustrate the cultural cohesiveness of the performer metaphor in a Western nature tourism setting to draw attention to the term's pervasiveness, its network of metaphoric entailments, and its generally unreflected upon meaning and reverberations. I examine struggles in using alternative metaphors and demonstrate ways the performer metaphor mediates processes of involvement with/in nature.  相似文献   

16.
In recent years, nitrate (NO3) contamination of groundwater has become a growing concern for people in rural areas in North China Plain (NCP) where groundwater is used as drinking water. The objective of this study was to evaluate groundwater resource level, to determine groundwater quality and to assess the risk of NO3 pollution in groundwater in Quzhou County in the NCP. Ordinary Kriging (OK) method was used to analyze the spatial variability of shallow groundwater level, groundwater electrical conductivity (EC) and NO3-N concentrations, and Indictor Kriging (IK) method was used to analyze the data with NO3-N concentrations equal or greater than the groundwater NO3 pollution threshold (20 mg L(-1)). The results indicated that groundwater level averaged 9.81 m, a level 6 m lower than in 1990. The spatial correlation distances for groundwater level, EC and NO3-N concentration were 21.93, 2.19 and 3.55 km, respectively. The contour map showed that shallow groundwater level areas extended from north to south across the County. Groundwater EC was above 3 dS m(-1) in the most part of the northern county. Groundwater NO3 pollution (NO3-N> or =20 mg L(-1)) mainly occurred in the County Seat areas due to wastewater irrigation and excessive fertilizer leaching from agricultural fields. At Henantuang town, besides suburban of the County Seat, groundwater was also contaminated by NO3 shown by the map generated using the IK method, which was not reflected in the map generated using the OK method. The map generated using the OK method could not reflect correctly the groundwater NO3 pollution status. The IK method is useful to assess the risk of NO3 pollution by giving the conditional probability of NO3 concentration exceeding the threshold value. It is suggested that risk assessment of NO3 pollution is useful for better managing groundwater resource, preventing soil salinization and minimizing NO3 pollution in groundwater.  相似文献   

17.
Marshes have been proposed as sites for phytoremediation of metals. The fate of metals within plant tissues is a critical issue for effectiveness of this process. In this paper we review studies that investigate the effects of plants on metals in wetlands. While most of these marsh plant species are similar in metal uptake patterns and in concentrating metals primarily in roots, some species retain more of their metal burden in below ground structures than other species, which redistribute a greater proportion of metals into above ground tissues, especially leaves. Storage in roots is most beneficial for phytostabilization of the metal contaminants, which are least available when concentrated below ground. Plants may alter the speciation of metals and may also suffer toxic effects as a result of accumulating them. Metals in leaves may be excreted through salt glands and thereby returned to the marsh environment. Metal concentrations of leaf and stem litter may become enriched in metals over time, due in part to cation adsorption or to incorporation of fine particles with adsorbed metals. Several studies suggest that metals in litter are available to deposit feeders and, thus, can enter estuarine food webs. Marshes, therefore, can be sources and well as sinks for metal contaminants. Phragmites australis, an invasive species in the northeast U.S. sequesters more metals below ground than the native Spartina alterniflora, which also releases more via leaf excretion. This information is important for the siting and use of wetlands for phytoremediation as well as for marsh restoration efforts.  相似文献   

18.
In May 2011, a highly mediatized direct action in the form of a “field liberation” took place in Flanders, Belgium, against a field trial of genetically modified potatoes. This direct action and its aftermath revealed the conflictual and antagonistic nature of the genetically modified organisms debate in Flanders. Consequently, it serves as a particularly suitable case to investigate the post-political thesis with regard to environmental discourse and politics. The aim of this paper is to investigate in what ways news media in their reporting contribute to processes of depoliticization and, resultantly, impede a democratic debate on the issues at stake. This paper attempts to provide an answer to this question based on a critical discourse analysis of the reporting by Flanders’ two generalist, elite newspapers, De Standaard and De Morgen and the alternative online news site DeWereldMorgen. The findings reveal the existence of three ideological cultures, which are characterized by different degrees of de/politicization. We conclude by discussing how this study adds to our understanding of the relation between the depoliticization of environmental discourse, democratic debate and twenty-first-century news media.  相似文献   

19.
Past and current experiences within many African countries confirm the hypothesis that the interaction between political stability, private investments and human rights is a critical element in the pursuit of sustainable development. Unfortunately, socio-economic and political crises African countries went through (and are still undergoing for some) have often occasioned a negative interaction between these three factors, with the consequence that the sustainable development process of Africa is yet slow comparatively to other developing regions in the world. Thus, in order to find the way forward, Africa needs more than ever before an effective leadership with rulers that are able to implement good governance principles in the functioning of the political system and also the participation of citizens, as far as possible, to public decision-making in respect of questions directly relevant to the sustainable development.  相似文献   

20.
The following study looks at how traditional, organic, cooperative farmers starting a new farming cooperative in the US Southwest communicate about their farming as a set of (sustainable) cultural practices. The study draws on environmental communication theory, the theory of the coordinated management of meaning, and Vandana Shiva’s three-tiered economic model to construct a communication-based framework through which to view farmers’ stories about sustainability. This framework is productive, showing how some Nuevo Mexicano farmers (and others) orient toward farming, sustenance, and human-nature relationships through community, family, heritage, and education. Moreover, in addition to a conceptualization of sustainability as specific practices for nurturing and enduring in environments, communities, and organizations/institutions, sustainability can be understood as embedded ecocultural and historical experience with cross-cultural parallels in land-based communities. This study advances the ethical duty of environmental communication to better understand the ways in which environmental discourse and ecocultural and material realities are imbricated, as well as the call for such discursive study to be grounded in phenomenological experience of the natural world.  相似文献   

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