897 resultados para Socio-ecological systems


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Integrated simulation models can be useful tools in farming system research. This chapter reviews three commonly used approaches, i.e. linear programming, system dynamics and agent-based models. Applications of each approach are presented and strengths and drawbacks discussed. We argue that, despite some challenges, mainly related to the integration of different approaches, model validation and the representation of human agents, integrated simulation models contribute important insights to the analysis of farming systems. They help unravelling the complex and dynamic interactions and feedbacks among bio-physical, socio-economic, and institutional components across scales and levels in farming systems. In addition, they can provide a platform for integrative research, and can support transdisciplinary research by functioning as learning platforms in participatory processes.

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Rising demands for agricultural products will increase pressure to further intensify crop production, while negative environmental impacts have to be minimized. Ecological intensification entails the environmentally friendly replacement of anthropogenic inputs and/or enhancement of crop productivity, by including regulating and supporting ecosystem services management in agricultural practices. Effective ecological intensification requires an understanding of the relations between land use at different scales and the community composition of ecosystem service-providing organisms above and below ground, and the flow, stability, contribution to yield, and management costs of the multiple services delivered by these organisms. Research efforts and investments are particularly needed to reduce existing yield gaps by integrating context-appropriate bundles of ecosystem services into crop production systems.

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This paper analyses and describes the semi-arid rangelands of southern Africa. These rangelands are found in the grassland, savanna and thicket biomes and comprise all the remaining land which does not support commercial rainfed agriculture, in extent some 778221 km2 (66% of South Africa). Although production is primarily driven by rainfall, rangeland management systems have been developed to cope with the uncertain climate and to ameliorate the impact of inter-annual variation in production. We describe the rangeland types that occur, provide an insight into their management and examine some constraints on livestock production which the socio-economic environment presents. We describe the grazing management systems which apply under the two land tenure systems, namely freehold and leasehold tenure, and discuss how each of these systems effects livestock production, management and resource condition.

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This paper makes a theoretical case for using these two systems approaches together. The theoretical and methodological assumptions of system dynamics (SD) and soft system methodology (SSM) are briefly described and a partial critique is presented. SSM generates and represents diverse perspectives on a problem situation and addresses the socio-political elements of an intervention. However, it is weak in ensuring `dynamic coherence'. consistency between the intuitive behaviour resulting from proposed changes and behaviour deduced from ideas on causal structure. Conversely, SD examines causal structures and dynamic behaviours. However, whilst emphasising the need for a clear issue focus, it has little theory for generating and representing diverse issues. Also, there is no theory for facilitating sensitivity to socio-political elements. A synthesis of the two called ‘Holon Dynamics' is proposed. After an SSM intervention, a second stage continues the socio-political analysis and also operates within a new perspective which values dynamic coherence of the mental construct - the holon - which is capable of expressing the proposed changes. A model of this holon is constructed using SD and the changes are thus rendered `systemically desirable' in the additional sense that dynamic consistency has been confirmed. The paper closes with reflections on the proposal and the need for theoretical consistency when mixing tools is emphasised.

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We provide new evidence on sea surface temperature (SST) variations and paleoceanographic/paleoenvironmental changes over the past 1500 years for the north Aegean Sea (NE Mediterranean). The reconstructions are based on multiproxy analyses, obtained from the high resolution (decadal to multidecadal) marine record M2 retrieved from the Athos basin. Reconstructed SSTs show an increase from ca. 850 to 950 AD and from ca. 1100 to 1300 AD. A cooling phase of almost 1.5 �C is observed from ca. 1600 AD to 1700 AD. This seems to have been the starting point of a continuous SST warming trend until the end of the reconstructed period, interrupted by two prominent cooling events at 1832 ± 15 AD and 1995 ± 1 AD. Application of an adaptive Kernel smoothing suggests that the current warming in the reconstructed SSTs of the north Aegean might be unprecedented in the context of the past 1500 years. Internal variability in atmospheric/oceanic circulations systems as well as external forcing as solar radiation and volcanic activity could have affected temperature variations in the north Aegean Sea over the past 1500 years. The marked temperature drop of approximately ~2 �C at 1832 ± 15 yr AD could be related to the 1809 АD ‘unknown’ and the 1815 AD Tambora volcanic eruptions. Paleoenvironmental proxy-indices of the M2 record show enhanced riverine/continental inputs in the northern Aegean after ca. 1450 AD. The paleoclimatic evidence derived from the M2 record is combined with a socio-environmental study of the history of the north Aegean region. We show that the cultivation of temperature-sensitive crops, i.e. walnut, vine and olive, co-occurred with stable and warmer temperatures, while its end coincided with a significant episode of cooler temperatures. Periods of agricultural growth in Macedonia coincide with periods of warmer and more stable SSTs, but further exploration is required in order to identify the causal links behind the observed phenomena. The Black Death likely caused major changes in agricultural activity in the north Aegean region, as reflected in the pollen data from land sites of Macedonia and the M2 proxy-reconstructions. Finally, we conclude that the early modern peaks in mountain vegetation in the Rhodope and Macedonia highlands, visible also in the M2 record, were very likely climate-driven.

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Background: The oral health conditions of indigenous peoples in Amazonia are closely associated with ecological and dietary changes related to interaction with non-Indians. Aim: The study investigated the incidence of caries in an indigenous community from Central Brazil focusing on gender differences. Subjects and methods: The research was conducted among the Xavante Indians and was based on longitudinal data collected in two surveys (1999 and 2004). The study included 128 individuals, 63 (49.2%) males and 65 (50.8%) females, divided in four age brackets (6-12, 13-19, 20-34, 35-60 years of age). The DMFT (decayed, missing and filled teeth) index and incidences (difference between 1999 and 2004) were calculated for each individual. The proportion of incidence was also calculated. Differences in caries risk between gender and age brackets were compared by parametric and non-parametric tests. Results: There were statistically significant differences in relation to caries incidence between age brackets and gender. The greatest incidence was observed in the 20-34 age bracket, which presented 3.30 new decayed teeth, twice the risk of the 6-12 age bracket (p0.01), chosen as reference. While females in most age groups did not show higher risk for caries when compared to males, there was a 4.04-fold risk in the 20-34 age bracket (p0.01). Conclusion: It is concluded that factors related to the social functions of each sex (gender issues) and differential access to information, health services, and education may help to understand the differences observed in the incidence of caries.

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Obesity is socio-culturally distributed; that is the prevalence of obesity is known to vary according to socio-cultural factors, including socio-economic position, social roles and circumstance, and cultural factors. Further, these socio-cultural patterns are complex and specific to sex, age, and sometimes racial groups, as well as type of society, with patterns of relationships observed in developed countries sometimes reversed in developing countries. As described in Chapter 4, there is little doubt of the importance of the changing physical environment to the increases in obesity observed over the past several decades. However, far less attention has been paid to investigating the potential contribution of socio-cultural factors and to changes in the socio-cultural environment over time to the current obesity pandemic. The mechanisms through which socio-cultural factors may influence body weight and risk for obesity are also not well understood. In discussing socio-cultural influences we refer to systems of social relations (roles and relationships that define class, gender, ethnicity, and other social factors) and the meanings attached to these (1). For the purposes of this chapter, we focus on the impact of social, economic, and value systems on individuals' obesity-related behaviors (particularly, certain eating patterns and physical inactivity). In particular, we examine socio-cultural categories (socio-economic status, ethnicity, marital/family roles) for which evidence exists that rates of obesity are differentially distributed. We have not focused on the role of physical environmental factors, which is covered in Chapter 4, and we have largely restricted our focus to developed countries, from where the majority of the evidence for socio-cultural influences on obesity is derived. Issues relating to influences on obesity in developing countries are covered in detail in Chapter 5. This chapter provides an overview of the impact of socio-cultural influences on obesity in developed countries, and considers the potential pathways through which these influences may operate. The chapter concludes by speculating about the potential impact of societal trends on future rates and patterns of obesity in developed countries.

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Issue addressed: Health programs have been part of the responsibility of Victorian school education for 90 years. Yet rarely have there been studies to identify what is happening in school health promotion, or what the differences between schools might be, particularly in relation to the socioeconomic status of the school community and whether the school is in a metropolitan or regional area. Methods: In 1997 all Victorian schools (primary and secondary) in the State, Catholic and Independent systems were sent questionnaires in order to promote broader awareness about health promotion, and to identify what health programs, policies and activities the schools believed existed within their school community. A response rate of 43% was achieved, and results were collated under the six domains of the Health Promoting School model as outlined by the Western Pacific Regional Office of the World Health Organisation. Data analysed in this paper compared highest versus lowest quartiles for socioeconomic status (SES), and schools in metropolitan Melbourne versus regional areas. Results: Most differences between schools based on socioeconomic status occurred in secondary schools and were related mainly to environmental policies and practices, use of back packs, the presence of safety policies, involvement of parents in school activities and the provision of services for mental and social health needs. All differences were in favour of the highest SES quartile schools. Environmental policies and procedures, and school-based health and welfare services were present more often in metropolitan schools than in regional and rural schools. Conclusion: Although there were notable differences between schools, the audit results pointed to more similarities than differences between schools in the highest and lowest SES quartiles for health-related policies and practices; there were even fewer differences between metropolitan and non-metropolitan schools. So what: Regardless of the actual advantages and disadvantages schools experience with respect to location or socioeconomic status, it is important to understand that school staff perceive that they can and do have reasonably comprehensive health policies, procedures and practices to address health issues. Nevertheless, clear differences between schools did emerge in certain health areas and findings will assist policy making and the allocation of limited resources.

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Purpose - Recently, Colac Otway Shire in Australia released its management plan for Lake Colac, claiming over-enrichment of the lake with nutrients and degraded water quality. This paper aims to investigate these claims by establishing a correlation between key water and ecological indicators and land uses.

Design/methodology/approach - Examines the correlation between impairment and stressors in Lake Colac. This was achieved by identifying the likely sources of pollutants into Lake Colac; identifying any existing monitoring program; and characterizing the water and sediment inputs. The likely impacts of increased nutrients and sediment levels on indigenous flora and fauna were also examined. The use of meiofauna (very small benthic metazoan animals) was investigated as an indicator of degraded sites. Plankton diversity as a measure of water health was also assessed.

Findings - Water quality in Lake Colac was found to vary both temporally and spatially, and exhibited low attainment against acceptable trigger values/objectives. At current levels the lake can be classified as poorly degraded. Likely sources of pollution were identified to be related to land uses in the catchments. The biota of the lake, investigated at four study sites, yielded a sparse, benthic macrofaunal assemblage that was dominated by oligochaetes. In contrast, an abundant and taxonomically diverse meiofaunal assemblage was noted. Future meiofaunal analyses are likely to resolve suitable biotic indicator species of free-living nematodes in response to land use and waterway threats specified in the study. Originality value - This work will provide a better understanding of integrated environmental systems to enable development of best management practices, thus transforming the way the land and water are used in the future. Following the present work, other key water and ecological indicators (increased dispersion and dominance of biological species) at five additional sites were studied. Alternative management options for the effluent generated at Colac Sewage Treatment Plant and possible ecological effects of each option were also evaluated. More recently, a sediment characterization study was also carried out at sensitive sites representative of locations where build up of sediments and algae outbreaks are reported. This will enable classification of sediment and evaluation of dredging options.


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This qualitative study investigated why women of low socio-economic status (SES) are less physically active than women of higher-SES. Semi-structured interviews were conducted with 19 high-, 19 mid- and 18 low-SES women. A social-ecological framework, taking into account intrapersonal, social and environmental level influences, was adopted to guide the development of interview questions and interpretation of data. Thematic analysis identified a number of key influences on physical activity that varied by SES. These included negative early life/family physical activity experiences (a consistent theme among those of low-/mid-SES); participation in a wider range of physical activities in leisure time (high-SES); greater priority given to television viewing (low-SES); lack of time due to work commitments (low-SES); lack of time due to family commitments (high-SES); and neighbourhood-level barriers (low-SES). Financial costs were not perceived as a key barrier by women in any SES group. Public health strategies aimed at reducing SES

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This paper explores Critical Success Factors (CSFs) in the transfer
of after-sales support-oriented knowledge from Information Technology (IT)
support organisations to enterprise customers, using Web-based self-service Systems (WSS). As it appears that best-in-class companies are ahead of the academic work in this area, we approached the topic through an exploratory CSF study of a best-in-class multinational IT services firm and identified 26 CSFs. Key findings from the study indicate that best-in-class IT service organisations may be cognisant of a range of factors relating to supporting customers, but are less aware of what is needed to support their own frontline support agents. Such organisations also lack an understanding of what is needed to provide enterprise support in the later stages of knowledge transfer, where enterprise customers can experience problems attempting to integrate resolutions. The study further showed that many aspects that might be characterised as encompassing socio-technical issues relating to the provision of web-based self-service are still poorly understood.

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This article categorizes four kinds of adverse effects to human health caused by ecosystem change: direct, mediated, modulated, and systems failure. The effects are categorized on their scale, complexity, and lag-time. Some but not all of these can be classified as resulting from reduced ecosystem services. The articles also explores the impacts that different socioeconomic–ecologic scenarios are likely to have on human health and how changes to human health may, in turn, influence the unfolding of four different plausible future scenarios. We provide examples to show that our categorization is a useful taxonomy for understanding the complex relationships between ecosystems and human well-being and for predicting how future ecosystem changes may affect human health.

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Although intranets appear to be ideal environments for employees to share knowledge quickly and efficiently, usage in practice appears limited. We report findings from two case studies that highlight three key issues limiting intranet utilisation for knowledge sharing: organisational structures and strategies, the impact of the receiver on sharer choices, and the availability of alternative channels for knowledge sharing. This study suggests that for companies to obtain more effective intranets, they need to better align organisational structures and strategies with intranet objectives, develop a comprehensive corporate communication plan, and find new ways to better link sharers with receivers’ knowledge needs.