共查询到20条相似文献,搜索用时 328 毫秒
1.
This paper first explores the shift now occurring in the science that provides the theoretical basis for forest conservation and management. The paper then presents the concepts of traditional ecological knowledge and traditional management systems and practise to provide background for two case studies that examine traditional knowledge and forest management practices of tribal communities in the Sariska region (Rajasthan, India) and of the indigenous Mapuche Pewenhce communities in the Andean mountains of southern Patagonia in Chile, underlining the special relationship these tribal and indigenous communities maintain with the forest and their usefulness in community-based native forest conservation. These examples of traditional ecological knowledge and traditional management systems suggest that it is important to focus on managing ecological processes, instead of products, and to use integrated ecosystem management. Recommendations to move forest management paradigms beyond the current view of ‘timber’ or ‘reserves’ and toward one of truly integrated use that adapt conservation approaches to local cultural representations of the environment are made. 相似文献
2.
Zhaoqing Yang Taiping Wang Tarang Khangaonkar Stephen Breithaupt 《Environmental Fluid Mechanics》2012,12(1):63-80
The interactions of physical processes between estuaries and upstream river floodplains are of great importance to the fish
habitats and ecosystems in coastal regions. Traditionally, a hydraulic analysis of floodplains has used one- or two-dimensional
models. While this approach may be sufficient for planning the engineering design for flood protection, it is inadequate when
floodwaters inundate the floodplain in a complex manner. Similarly, typical estuarine and coastal modeling studies do not
consider the effect of upstream river floodplains because of the technical challenge of modeling wetting and drying processes
in floodplains and higher bottom elevations in the upstream river domain. While various multi-scale model frameworks have
been proposed for modeling the coastal oceans, estuaries, and rivers with a combination of different models, this paper presents
a modeling approach for simulating the hydrodynamics in the estuary and river floodplains, which provides a smooth transition
between the two regimes using an unstructured-grid, coastal ocean model. This approach was applied to the Skagit River estuary
and its upstream river floodplain of Puget Sound along the northwest coast of North America. The model was calibrated with
observed data for water levels and velocities under low-flow and high-flood conditions. This study successfully demonstrated
that a three-dimensional estuarine and coastal ocean model with an unstructured-grid framework and wetting-drying capability
can be extended much further upstream to simulate the inundation processes and the dynamic interactions between the estuarine
and river floodplain regimes. 相似文献
3.
4.
Advances in computing power in the past 20 years have led to a proliferation of spatially explicit, individual-based models of population and ecosystem dynamics. In forest ecosystems, the individual-based models encapsulate an emerging theory of "neighborhood" dynamics, in which fine-scale spatial interactions regulate the demography of component tree species. The spatial distribution of component species, in turn, regulates spatial variation in a whole host of community and ecosystem properties, with subsequent feedbacks on component species. The development of these models has been facilitated by development of new methods of analysis of field data, in which critical demographic rates and ecosystem processes are analyzed in terms of the spatial distributions of neighboring trees and physical environmental factors. The analyses are based on likelihood methods and information theory, and they allow a tight linkage between the models and explicit parameterization of the models from field data. Maximum likelihood methods have a long history of use for point and interval estimation in statistics. In contrast, likelihood principles have only more gradually emerged in ecology as the foundation for an alternative to traditional hypothesis testing. The alternative framework stresses the process of identifying and selecting among competing models, or in the simplest case, among competing point estimates of a parameter of a model. There are four general steps involved in a likelihood analysis: (1) model specification, (2) parameter estimation using maximum likelihood methods, (3) model comparison, and (4) model evaluation. Our goal in this paper is to review recent developments in the use of likelihood methods and modeling for the analysis of neighborhood processes in forest ecosystems. We will focus on a single class of processes, seed dispersal and seedling dispersion, because recent papers provide compelling evidence of the potential power of the approach, and illustrate some of the statistical challenges in applying the methods. 相似文献
5.
A. Jarernpornnipat O. Pedersen K. R. Jensen S. Boromthanarat S. Vongvisessomjai P. Choncheanchob 《Journal of Coastal Conservation》2003,9(2):135-146
Bandon Bay (Surat Thani Province) is one of the most productive coastal areas in southern Thailand. The Tapi River and 18
channels are the main sources of freshwater, nutrients, organic matter and sediment to the bay and the loading of freshwater
and nutrients provide essential support for the production of phytoplankton in the estuarine ecosystem. Bandon Bay is important
as natural spawning, nursery and feeding grounds for shellfish such as oysters, blood cockles, green mussels, short-necked
clams, mud crabs and shrimps, and the estuary also serves as an excellent area for mariculturing of shellfish. In fact, oysters
and blood cockles cultured in Bandon Bay are now being exported worldwide. However, Bandon Bay is also a textbook example
of overexploitation of coastal resources in the tropics including all the derived changes in the estuarial ecosystem with
severe socio-economic consequences. Hence, there is an urgent need for setting up an integrated management plant for a sustainable
use of shellfish resources in Bandon Bay. The present study attempts to integrate water quality simulation results, socio-economic
data and information on existing shellfish resource use in the process of proposing a set of sustainable management strategies
for shellfish resources in Bandon Bay. These strategies involve: (1) using water quality modeling to monitor ecological and
environmental changes in shellfish culture beds and their natural habitats in the process of setting up a master plan for
management of waste water discharge into Bandon Bay; (2) zoning of shellfish mariculture in the coastal area in order to solve
conflicts between resource users; (3) setting up a clear system for taxation of mariculture where the revenue may be used
for (4) setting up and managing mangrove strips as filters of pollution and sediment around Bandon Bay; and finally (5) it
is suggested to form a committee with members representing all relevant stakeholders plus the local government in order to
work on resolving the existing and potential future conflicts over resource usage in Bandon Bay. This methodology may be seen
as an important contribution towards a Bandon Bay sustainable management approach, based on the principles of integrated coastal
zone management because it is science-based and takes into consideration the needs and perceptions of people involved in coastal
resource extraction. 相似文献
6.
M. Àngels ColomerAntoni Margalida Delfí SanuyMario J. Pérez-Jiménez 《Ecological modelling》2011,222(1):33-47
The models used for ecosystems modeling are generally based on differential equations. However, in recent years new computational models based on biological processes, or bioinspired models, have arisen, among which are P systems. These are inspired by the functions of cells and present important advantages with respect to traditional models, such as a high computational efficiency, modularity and their ability to work in parallel. They are simple, individual-based models that use biological parameters that can be obtained experimentally. In this work, we present the framework for a model based on P systems applied to the study of an ecosystem in which three avian scavengers (predators) interact with 10 wild and domestic ungulates (preys). The computation time for 100 repetitions, corresponding to 14 simulation years each, with an initial population composed of 385,422 individuals, was 30 min. Our results suggest that the model presented, based on P systems, correctly simulates the population dynamics in the period of time analyzed. We discuss the usefulness of this tool in simulating complex ecosystems dynamics to aid managers, conservationists and policy-makers in making appropriate decisions for the improvement of management and conservation programs. 相似文献
7.
Breininger DR Nichols JD Duncan BW Stolen ED Carter GM Hunt DK Drese JH 《Ecology》2010,91(11):3354-3364
Many ecosystems are influenced by disturbances that create specific successional states and habitat structures that species need to persist. Estimating transition probabilities between habitat states and modeling the factors that influence such transitions have many applications for investigating and managing disturbance-prone ecosystems. We identify the correspondence between multistate capture-recapture models and Markov models of habitat dynamics. We exploit this correspondence by fitting and comparing competing models of different ecological covariates affecting habitat transition probabilities in Florida scrub and flatwoods, a habitat important to many unique plants and animals. We subdivided a large scrub and flatwoods ecosystem along central Florida's Atlantic coast into 10-ha grid cells, which approximated average territory size of the threatened Florida Scrub-Jay (Aphelocoma coerulescens), a management indicator species. We used 1.0-m resolution aerial imagery for 1994, 1999, and 2004 to classify grid cells into four habitat quality states that were directly related to Florida Scrub-Jay source-sink dynamics and management decision making. Results showed that static site features related to fire propagation (vegetation type, edges) and temporally varying disturbances (fires, mechanical cutting) best explained transition probabilities. Results indicated that much of the scrub and flatwoods ecosystem was resistant to moving from a degraded state to a desired state without mechanical cutting, an expensive restoration tool. We used habitat models parameterized with the estimated transition probabilities to investigate the consequences of alternative management scenarios on future habitat dynamics. We recommend this multistate modeling approach as being broadly applicable for studying ecosystem, land cover, or habitat dynamics. The approach provides maximum-likelihood estimates of transition parameters, including precision measures, and can be used to assess evidence among competing ecological models that describe system dynamics. 相似文献
8.
Many nearshore restoration projects are currently underway at coastal locations where human influence and development have disrupted natural habitat and coastal ecological systems. The objectives of these projects in general are to restore the lost estuarine functions to the tidal marshland. Often these projects are conducted with little understanding of the potential effects of other nearby projects within the ecosystem, and similarly, it is easy to neglect the effect of the local project on the larger estuarine scale. In this paper, a modeling study is presented to evaluate the hydrodynamic responses of multiple restoration projects and their cumulative effect in the Snohomish River estuary in Washington, USA. The concept of absolute mean tidal transport is introduced and used to measure the cumulative effect of the proposed restoration projects on the estuarine hydrodynamics. The results show that the hydrodynamic responses due to multiple restoration projects are additive in the estuary, and the effect is nonlinear. The hydrodynamic response under restoration conditions depends on the size of the restoration area and the geometric configuration of the existing river channels. Within a complex braided estuary such as the Snohomish, the influence of a specific restoration project is not only experienced locally, but also found to significantly affect tidal transport in all distributary branches within the system. 相似文献
9.
David C. Natcher 《国际发展与全球生态学杂志》2013,20(4):363-374
Recognizing the limitations common to both centralized and privatized management regimes, institutionalized resource management is beginning to incorporate the knowledge and skills of local resource users, coupled with the enabling policies and legislation of state systems, to arrive at cooperative approaches to resource management. These varying and dynamic approaches to resource management have been compelled largely through the recognition of the limited capabilities of existing management systems to adapt effectively to ecosystem change and the evolving needs of resource users. These cooperative approaches to management should not, however, be considered an institutional end-point, but rather a phase in the perpetual transition of a social system; each unique in character and individually variable depending on the resource being managed, the political climate in which management occurs, as well as the differing strategies employed by resource users to enact institutional change. Drawing from the experiences of the Whitefish Lake First Nation of Alberta, Canada, this paper presents a brief overview of the evolution of resource management theory, grounded in the real-world formation of the Whitefish Lake First Nation — Province of Alberta Cooperative Management Agreement. 相似文献
10.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years,
the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled
fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus
influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development
policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales
of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences
of development plans are seldom considered). Some international conservation organizations are testing promising new approaches
to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful
examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources,
they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance
agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected
areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered
as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with
the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major
role in the design and implementation of any fishing management actions. 相似文献
11.
This paper explores the prospects for combining elements of the ecological and policy sciences to form a substantive and effective science of ecological policy design. This exploration is made through a case study whose specific focus is the management problem posed by competition between man and an insect (the spruce budworm, Choristoneura fumiferana) for utilization of coniferous forests in the Canadian Province of New Brunswick. We used this case study as a practical testing ground in which we examined the relative strengths, weaknesses, and complementarities of various aspects of the policy design process. Where existing approaches proved wanting, we sought to develop alternatives and to test them in turn. In particular, we used a combination of simulation modeling and topological approaches to analyze the space-time dynamics of this ecosystem under a variety of natural and managed conditions. Explicit consideration was given to the development of invalidation tests for establishing the limits of model credibility. An array of economic, social, and environmental indicators was generated by the model, enabling managers and policy makers to evaluate meaningfully the performance of the system under a variety of management proposals. Simplified versions of the models were constructed to accomodate several optimization procedures, including dynamic programming, which produced trial policies for a range of possible objectives. These trial policies were tested in the more complex model versions and heuristically modified in dialogue with New Brunswick's forest managers. We explored the role of utility functions for simplifying and contrasting policy performance measures, paying special attention to questions of time preferences and discounting. Finally, the study was shaped by a commitment to transfer the various models and policy design capabilities from their original academic setting to the desks and minds of the practicing managers and politicians. An array of workshops, model gaming sessions, and nontraditional communication formats was developed and tested in pursuit of this goal.This paper reports some specific management policies developed, and some general lessons for ecological policy design learned in the course of the study. 相似文献
12.
13.
This contribution presents an introduction to a series of papers on integrated scientific approaches presented at the San
Feliu Euroconference on transdisciplinary coastal management research. Coastal management is a challenging area for the integration
of social and natural sciences. The papers provide a basis for ongoing cross-disciplinary research. 相似文献
14.
Corinna Abesser Derek Clarke Andrew G. Hughes Nick S. Robins 《Journal of Coastal Conservation》2017,21(5):595-614
Coastal dunes are delicate systems that are under threat from a variety of human and natural influences. Groundwater modelling can provide a better understanding of how these systems operate and can be a useful tool towards the effective management of a coastal dune system, e.g. by identifying strategically important locations for flora and fauna and guiding the planning of management operations through predicting impacts from climatic change, sea level rise and land use management. Most dune systems are small, typically of the size 10–100 km2, compared with inland groundwater systems. Applying conventional groundwater modelling approaches to these small systems presents a number of challenges due to the local scale of the system and the fact that the system boundaries (sea, drains, ponds etc.) are close to the main body of the aquifer. In this paper, two case studies will be presented using different modelling approaches to understand the groundwater balance in two dune systems in the UK. The studies demonstrate that, although conventional hydraulic models can describe the general system behaviour, a fuller understanding of the recharge mechanisms and system boundaries is needed to represent adequately system dynamics of small groundwater systems. 相似文献
15.
《Ecological modelling》2005,187(4):513-523
Phytoplankton growth in estuaries is controlled by factors such as flushing, salinity tolerance, light, nutrients and grazing. Here, we show that biodiversity of estuarine phytoplankton is related to flushing, and illustrate this for some European estuaries.The implications for the definition of reference conditions for quality elements in estuaries of different types are examined, leading to the conclusion that constraints on the number of estuarine and coastal types that may be defined for management purposes require that quality classes take into account natural variability within types, in order to be ecologically meaningful. We develop a screening model to predict the growth rate required for a phytoplankton species to be present under different flushing conditions and apply it to estuaries in the EU and US to show how changes in physical forcing may alter biodiversity. Additional results are presented on the consequences for eutrophication, showing that changes in residence time may interact with species-specific nutrient uptake rates to cause shifts in species composition, potentially leading to effects such as harmful algal blooms.We discuss applications for integrated coastal zone management, and propose an approach to normalization of estuarine phytoplankton composition as regards species numbers. 相似文献
16.
Jesús Cambrollé Juan Manuel Mancilla-Leytón Sara Muñoz-Vallés Beatriz Morenza-Barrera Manuel Enrique Figueroa 《Journal of Coastal Conservation》2018,22(6):1201-1207
Human pressure has been exponentially growing during recent decades in coastal areas, which have led to drastic losses of biodiversity in coastal ecosystems. The current conservation status of many coastal plant species is directly related to a lack of environmental criteria in the urban planning of coastal areas over recent decades. This study aimed to evaluate the evolution, over the last 9 years, of the conservation status of various populations of the endangered plant Glaucium flavum, exploring the extent to which human pressure and different management strategies practiced in the coastal areas where the populations are established have affected the conservation status of the species. The populations analysed have evolved in a different manner over the last 9 years, as have their threat factors, and a relationship was evident between their conservation status and the evolution of these different threat factors. Our results indicate that an appropriate planning of local management actions, such as the installation of walkways or the successful eradication of invasive species, may be determinant factors for successful conservation of the coastal vegetation. The presence of species that are sensitive to slight changes in the ecosystem, and the main factors that govern the plant performance of these species, must be given full consideration in decision-making processes of coastal planning and management. 相似文献
17.
Ecological-Economic Modeling for Biodiversity Management: Potential, Pitfalls, and Prospects 总被引:3,自引:0,他引:3
FRANK WÄTZOLD††† MARTIN DRECHSLER CLAIRE W. ARMSTRONG† STEFAN BAUMGÄRTNER‡ VOLKER GRIMM REAS HUTH CHARLES PERRINGS§‡‡‡ HUGH P. POSSINGHAM JASON F. SHOGREN†† ERS SKONHOFT‡‡ JANA VERBOOM-VASILJEV§§ CHRISTIAN WISSEL 《Conservation biology》2006,20(4):1034-1041
Abstract: Ecologists and economists both use models to help develop strategies for biodiversity management. The practical use of disciplinary models, however, can be limited because ecological models tend not to address the socioeconomic dimension of biodiversity management, whereas economic models tend to neglect the ecological dimension. Given these shortcomings of disciplinary models, there is a necessity to combine ecological and economic knowledge into ecological-economic models. It is insufficient if scientists work separately in their own disciplines and combine their knowledge only when it comes to formulating management recommendations. Such an approach does not capture feedback loops between the ecological and the socioeconomic systems. Furthermore, each discipline poses the management problem in its own way and comes up with its own most appropriate solution. These disciplinary solutions, however, are likely to be so different that a combined solution considering aspects of both disciplines cannot be found. Preconditions for a successful model-based integration of ecology and economics include (1) an in-depth knowledge of the two disciplines, (2) the adequate identification and framing of the problem to be investigated, and (3) a common understanding between economists and ecologists of modeling and scale. To further advance ecological-economic modeling the development of common benchmarks, quality controls, and refereeing standards for ecological-economic models is desirable. 相似文献
18.
Paul M. Thompson Ben Wilson † Kate Grellier and Philip S. Hammond† 《Conservation biology》2000,14(5):1253-1263
Abstract: Traditionally, marine resources have been managed such that controls on new developments are implemented only when harmful effects on other environmental or economic interests can be demonstrated. This approach poses particular problems for the conservation of coastal cetaceans because potential threats to their populations are diverse and likely to interact, individual threats may result from multiple sources, and the problems inherent in studying cetaceans result in considerable scientific uncertainty and low statistical power to detect any effects. Consequently, many countries are adopting integrated coastal management programs and precautionary management principles. In practice, however, issues continue to be dealt with within traditional frameworks that require demonstration of harm. Because cetaceans are long-lived, they demand long-term studies, and populations could decline to dangerously low levels before management action is taken. We illustrate these problems using a case study from the Moray Firth, Scotland. This inshore area will soon be designated and managed as a "special area of conservation" to protect bottlenose dolphins ( Tursiops truncatus ) under the European Community's Habitats Directive. The population is small and isolated, and it faces a wide range of potential threats, but there remains considerable uncertainty over the magnitude of each threat. We combined power analysis and population viability analysis to explore the relative consequences of adopting either traditional or precautionary approaches to management. In this case, our results reaffirm the need for precautionary management. More generally, we illustrate how this approach can be used to provide a more scientific basis for determining the level of precaution required to address particular management issues in this and other marine systems. 相似文献
19.
The Euroconference on Coastal Management Research held in San-Feliu de Guixols, Spain, in December 1997 brought together scientists
from a great variety of disciplines in the natural and social sciences, in a search for modes of transdisciplinary cooperation
in the context of integrated coastal management. During the conference the participants discussed which interactions among
disciplines are required for different coastal issues. Discussion groups each focused on a particular type of coastal environment,
characterized by a particular type and degree of development. The group discussions were inspired by background papers which
were prepared for this purpose by invited speakers. A selection of these background papers were redrafted on the basis of
the conference outcome, and are published in this issue of theJournal of Coastal Conservation. The reports of the discussion groups are published in a conference proceedings booklet issued by EMAPS (1998), the European
Polar and Marine Sciences Secretariat. A synthesis of ideas on the challenge of transdisciplinarity, expressed during the
discussion group sessions, is presented in this introduction. The statements reflect opinions or suggestions which received
broad support from the participants; they should not be taken as proven knowledge. 相似文献
20.
In order to understand the reproductive contribution among migratory types in the Japanese eel, Anguilla japonica, otolith strontium (Sr) and calcium (Ca) concentrations by X-ray electron microprobe analysis were examined for 37 silver
eels collected in Kii Channel off Shikoku Island during the spawning migration season. The wide range of otolith Sr:Ca ratios
indicated that the habitat use of A. japonica was not obligatory but facultative among fresh, brackish and marine waters during their growth phases after recruitment to
the coastal areas as glass eels. Three migratory types, which were categorized as river eels, estuarine eels and sea eels
were found. The estuarine eels were dominant (59%), followed by sea eels (22%) and river eels (19%). The low proportion of
river eels from the spawning migration season suggested that the estuarine and sea eels inhabiting the nearby coastal areas
might make a larger reproductive contribution to the next generation in this area. 相似文献