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81.
Positives and pathologies of natural resource management on private land‐conservation areas
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In managed natural resource systems, such as fisheries and rangelands, there is a recognized trade‐off between managing for short‐term benefits and managing for longer term resilience. Management actions that stabilize ecological attributes or processes can improve productivity in the supply of ecosystem goods and services in the short term but erode system resilience at longer time scales. For example, fire suppression in rangelands can increase grass biomass initially but ultimately result in an undesirable, shrub‐dominated system. Analyses of this phenomenon have focused largely on how management actions influence slow‐changing biophysical system attributes (such as vegetation composition). Data on the frequency of management actions that reduce natural ecological variation on 66 private land‐conservation areas (PLCAs) in South Africa were used to investigate how management actions are influenced by manager decision‐making approaches, a largely ignored part of the problem. The pathology of natural resource management was evident on some PLCAs: increased focus on revenue‐generation in decision making resulted in an increased frequency of actions to stabilize short‐term variation in large mammal populations, which led to increased revenues from ecotourism or hunting. On many PLCAs, these management actions corresponded with a reduced focus on ecological monitoring and an increase in overstocking of game (i.e., ungulate species) and stocking of extralimitals (i.e., game species outside their historical range). Positives in natural resource management also existed. Some managers monitored slower changing ecological attributes, which resulted in less‐intensive management, fewer extralimital species, and lower stocking rates. Our unique, empirical investigation of monitoring‐management relationships illustrates that management decisions informed by revenue monitoring versus ecological monitoring can have opposing consequences for natural resource productivity and sustainability. Promoting management actions that maintain resilience in natural resource systems therefore requires cognizance of why managers act the way they do and how these actions can gradually shift managers toward unsustainable strategies. 相似文献
82.
JOHN S. HICKS MARK A. BURGMAN JULIAN N. MAREWSKI FIONA FIDLER GERD GIGERENZER 《Conservation biology》2012,26(5):760-768
Abstract: The Tiwi people of northern Australia have managed natural resources continuously for 6000–8000 years. Tiwi management objectives and outcomes may reflect how they gather information about the environment. We qualitatively analyzed Tiwi documents and management techniques to examine the relation between the social and physical environment of decision makers and their decision‐making strategies. We hypothesized that principles of bounded rationality, namely, the use of efficient rules to navigate complex decision problems, explain how Tiwi managers use simple decision strategies (i.e., heuristics) to make robust decisions. Tiwi natural resource managers reduced complexity in decision making through a process that gathers incomplete and uncertain information to quickly guide decisions toward effective outcomes. They used management feedback to validate decisions through an information loop that resulted in long‐term sustainability of environmental use. We examined the Tiwi decision‐making processes relative to management of barramundi (Lates calcarifer) fisheries and contrasted their management with the state government's management of barramundi. Decisions that enhanced the status of individual people and their attainment of aspiration levels resulted in reliable resource availability for Tiwi consumers. Different decision processes adopted by the state for management of barramundi may not secure similarly sustainable outcomes. 相似文献
83.
84.
High rates of extra-pair young in the pair-living fat-tailed dwarf lemur, Cheirogaleus medius 总被引:6,自引:0,他引:6
J. Fietz H. Zischler C. Schwiegk J. Tomiuk K. H. Dausmann J. U. Ganzhorn 《Behavioral ecology and sociobiology》2000,49(1):8-17
Cheirogaleids are one of the most primitive extant primate taxa in the world. Their lifestyle and mating system, therefore,
have been considered to be representative for social systems in primate ancestors. Accepted models of social evolution in
primates state that pair-bonding has evolved secondarily from diurnal group-living taxa and should therefore be constrained
primarily to diurnal species. In contrast to these assumptions, the nocturnal fat-tailed dwarf lemur (Cheirogaleus medius) lives in permanent pairs, with obligate paternal care probably representing the evolutionary basis of pair-living. In this
sociobiological field study, we analyzed the reproduction strategy of C. medius in the tropical forest of western Madagascar. In the rainy seasons from 1995 to 1999, 173 individuals of C. medius were captured and individually marked and 131 were genetically characterized through seven microsatellite loci. Additionally,
36 of these individuals were radio-tracked and observed. For 53 genotyped individuals, including 16 offspring, information
about pair-bonding and family structure was known from field observations. Genetic analyses revealed that yearlings and infants
living with an adult pair were in all cases sibs of the social mother. However, C. medius does not restrain from extra-pair copulations (EPCs) and a high rate of extra-pair paternity (44%) was detected. Males sired
offspring with their female partners as well as with extra-pair females within the same year, indicating that males may increase
their reproductive success by EPCs without necessarily running the risk of cuckoldry. Females on the other hand do not seem
to run the risk of reduced paternal care, either because males cannot detect relatedness of young, or because they might even
increase their inclusive fitness by raising offspring of closely related males. Since females reproduce preferentially with
territory holders and no paternity could be assigned to floating males, superior genetic quality of the males might be crucial
for female choice.
Received: 12 January 2000 / Revised: 15 August 2000 / Accepted: 26 August 2000 相似文献
85.
Moira J. Calder 《Local Environment》2013,18(7):671-686
In this paper we examine and compare communication processes aimed at building social networks and increasing citizen engagement in two communities participating in a municipal sustainability planning (MSP) pilot programme in Alberta, Canada, initiated by the Alberta Urban Municipalities Association (AUMA). Data were gathered through qualitative semi-structured interviews and documentary review. In soliciting citizen engagement, each community utilised a variety of communication methods, based on available resources and on-going evaluation of community responses. In both cases, citizens developed a shared vision of a preferred future for their community, aided by a reconfiguration of their internal and external social networks. In addition to drawing upon and strengthening bonding relationships within the community, bridging relationships with external actors and agencies promoted knowledge mobilisation that aided in planning and transitioning towards sustainability. Both communities faced challenges as well, which the authors discuss in relation to the sustainability of MSP planning. 相似文献
86.
CHRIS SANDBROOK IVAN R. SCALES BHASKAR VIRA WILLIAM M. ADAMS 《Conservation biology》2011,25(2):285-294
Abstract: Debate on the values that underpin conservation science is rarely based on empirical analysis of the values conservation professionals actually hold. We used Q methodology to investigate the values held by international conservation professionals who attended the annual Student Conference in Conservation Science at the University of Cambridge (U.K.) in 2008 and 2009. The methodology offers a quantitative means of examining human subjectivity. It differs from standard opinion surveys in that individual respondents record the way they feel about statements relative to other statements, which forces them to focus their attention on the issues they believe are most important. The analysis extracts the diverse viewpoints of the respondents, and factor analysis is used to reduce the viewpoints to a smaller set of factors that reflect shared ways of thinking. The junior conservation professionals attending the conference did not share a unifying set of core values; rather, they held a complex series of ideas and a plurality of opinions about conservation and how it should be pursued. This diversity of values empirically challenges recent proposals for conservation professionals to unite behind a single philosophy. Attempts to forge an artificial consensus may be counterproductive to the overall goals conservation professionals are pursuing. 相似文献
87.
In this paper we developed a general stage-structured, Leslie-type model, suitable to simulate dynamics of soil arthropods under typical Mediterranean conditions. In order to explore arthropods’ life-history strategies in relation to enhanced spatial heterogeneity of the Mediterranean ecosystems, metapopulation characteristics were considered and different habitat quality regimes, in terms of dominant microclimatic conditions, were taken into account. Environmental stochasticity in temperature and humidity was incorporated into the model, and an elasticity analysis was conducted to quantify contribution of different life-history traits to metapopulation growth rate. The application of the model revealed well-known life-cycle characteristics of Mediterranean arthropods, such as seasonally fluctuating population sizes and skewing phenologies, a fact that confirms models’ reliability. Furthermore, the model seems able to elucidate controversial points of the animals’ life-cycle development, such as the long-term maintenance of populations in the field and the underlying mechanisms related to the adjustment to the specific features of the Mediterranean ecosystem. Subpopulations inhabiting various microsites display different dynamics and the interaction between these subpopulations, via dispersion, seems to be able to ensure stochastic equilibrium for the system. Dispersal appears to play a decisive role, allowing arthropods to conform to spatial severities and habitats fragmentation, rescuing individuals and recolonizing previously extinct habitats. 相似文献
88.
Abstract: The search for generalities in ecology has often been thwarted by contingency and ecological complexity that limit the development of predictive rules. We present a set of concepts that we believe succinctly expresses some of the fundamental ideas in conservation biology. (1) Successful conservation management requires explicit goals and objectives. (2) The overall goal of biodiversity management will usually be to maintain or restore biodiversity, not to maximize species richness. (3) A holistic approach is needed to solve conservation problems. (4) Diverse approaches to management can provide diverse environmental conditions and mitigate risk. (5) Using nature's template is important for guiding conservation management, but it is not a panacea. (6) Focusing on causes not symptoms enhances efficacy and efficiency of conservation actions. (7) Every species and ecosystem is unique, to some degree. (8) Threshold responses are important but not ubiquitous. (9) Multiple stressors often exert critical effects on species and ecosystems. (10) Human values are variable and dynamic and significantly shape conservation efforts. We believe most conservation biologists will broadly agree these concepts are important. That said, an important part of the maturation of conservation biology as a discipline is constructive debate about additional or alternative concepts to those we have proposed here. Therefore, we have established a web‐based, online process for further discussion of the concepts outlined in this paper and developing additional ones. 相似文献
89.
丁琳琳 《中国环境管理干部学院学报》2011,(6):58-61
建设"国际旅游名城"不可或缺的人力资源之一是高素质的涉外旅游人才。从秦皇岛"旅游立市"及创建"国际旅游名城"的大背景出发,分析秦皇岛面临的国际旅游发展机遇,阐述涉外旅游人才的种类和含义,并针对所需人才特点提出了培养思路和策略。 相似文献
90.
C. A. Kessler 《Environment, Development and Sustainability》2008,10(2):233-247
In Bolivia, recent decentralisation policies have broadened the participation of local actors in development processes. However,
development is far from sustainable, and poverty and natural resources degradation still increase. The challenge is to develop
strategies that achieve the genuine participation of poor farmers in natural resources management and sustainable development.
The logical strategy, which was developed and validated in five Bolivian mountain villages, is an example. In this strategy,
first a solid foundation for sustainable development is laid, with activities focussing on five basic conditions for sustainable
development in rural villages: leadership and organisation, responsible participation, effective collaboration, mutual trust
and environmental awareness. The results show that the existence of a solid foundation is crucial for the success of other
development activities, such as soil and water conservation activities. However, given that 2 years after the project’s withdrawal
the firmness of the foundation had slightly weakened, it was concluded that a better integration of these villages in local
development processes is essential to profit from the new dynamics. This is especially true for soil and water conservation.
To achieve this integration, municipalities—with the support of international development agencies—must be encouraged to invest
in laying this solid foundation in rural villages and in facilitating follow-up activities to keep the dynamic process going.
This study shows that such investments result in better organised villages, more equality, and the genuine participation of
more people in sustainable village development. Effective collaboration and accountability at institutional level are, however,
required. 相似文献