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1.
This article examines current neoliberal forces in the Torres Strait tropical rock lobster (TRL) fishery and their likely impacts on the lives of indigenous Islanders. It describes how neoliberal principles of market governance, commodification of natural resources, profit maximization, individualization and property rights are at odds with Islander rights, values, sense of place, and institutions of knowledge, tenure and practice. It argues that proposed fisheries measures based on neoliberal imperatives could cause important conflicts and create high social, political, and economic costs. The TRL fishery is integral to Islanders’ aspiration of self-determination and economic autonomy. A more holistic vision inclusive of Islander perspectives is necessary if management of the TRL fishery is to be truly socially and culturally appropriate.  相似文献   

2.
The EU Blue Growth Agenda targets maritime economic activities that have the sea and the coasts as drivers. These activities are supported by marine Ecosystem Services (ES) in combination, or not, with abiotic outputs from the marine natural capital. This paper analyses Blue Growth activities with regards to the demand and supply of marine ES and Good Environmental Status (GES). The results show that marine provisioning ES support aquaculture and blue biotechnology, while blue energy is supported by marine provisioning ES and by abiotic provisioning, and abiotic provisioning supports extraction of marine mineral resources. Maritime, coastal and cruise tourism is supported by cultural marine ES and cultural settings dependent on marine abiotic structures. All these multi-sectoral economic activities depend on healthy marine and coastal ecosystems that are provided by regulating and maintenance ES combined with the abiotic regulation and maintenance by natural marine physical structures and processes. In order to balance concurrent sectoral interests and achieve sustainable use of marine resources there is the need to consider indicators for demand for ES, which are social and economically driven, and for the supply, which are dependent on ecosystems capacity to provide the required marine ES. Some of the actions foreseeing GES are already anticipated in legislation that underpin Blue Growth, whilst others could benefit from additional regulation, particularly in what concern the exploration and exploitation of marine mineral and biological resources. Blue Growth options require navigating trade-offs between economic, social and environmental aspects.  相似文献   

3.
The ability to robustly predict future shoreline position under the influence of changing waves and sea-level rise is a key challenge to scientists and engineers alike. While extrapolating a linear trend out in time is a common baseline approach, the recent development of a number of empirical shoreline models allows the prediction of storm and annual-scale variability as well. The largest constraint in applying these models is the availability of high quality, adequate duration data sets in order to calibrate model free parameters. This contribution outlines several such models and discusses the monitoring programs required to calibrate and hindcast shoreline change from 1 to 10 years at two distinct beach types: a storm-dominated site and the second exhibiting a large seasonal variability. The seasonally-dominated site required longer data sets but was less sensitive to sampling interval, while the storm-dominated site converged on shorter, more frequently sampled data sets. In general, calibration based on a single year of observed shorelines resulted in a large range of model skill and was not considered robust. Monitoring programs of at least two years, with shorelines sampled at dt  30 days were sufficient to determine initial estimates of calibration coefficients and hindcast short-term (1–5 years) shoreline variability. In the presence of unresolved model processes and noise, hindcasting longer (5 + years) data sets required longer (5 + years) calibration data sets, particularly when sampling intervals exceeded 60 days.  相似文献   

4.
Although New Zealand rock lobster (Jasus edwardsii) fisheries can be assessed with a sophisticated Bayesian length‐based model, these assessments are expensive and time consuming; they cannot be conducted for each area every year. Harvest control rules are increasingly important management tools in New Zealand rock lobster fisheries. Recent work has developed and evaluated procedures for rebuilding or maintaining lobster stocks based on criteria agreed by stakeholders. Most management procedures depend on a single abundance index, often catch per unit of effort (CPUE). When management procedures react slowly to changes in vulnerable biomass, allowable catches get out of phase with the stock, causing large oscillations in both catches and CPUE. Lags between data and management actions and “latent years” are features of rules that reduce responsiveness. This study explores ways to improve the responsiveness of harvest control rules by using additional data to predict changes in vulnerable biomass. Four data sets are examined: CPUE trends, pre‐recruit indices, puerulus settlement indices, and size frequencies. Only pre‐recruit indices, which were explored with a simple delay‐difference model based on parameter estimates from recent assessments, appeared to have immediate potential for use in improving management procedures.  相似文献   

5.
We describe a multi‐stock, length‐based Bayesian assessment model for New Zealand spiny lobster (Jasus edwardsii) fisheries. This model allows simultaneous modelling of two or more stocks with a mixture of common and stock‐specific parameters: recruitment is always stock‐specific, but any other parameter can be specified as either common or stock‐specific. Common parameters are estimated from a wider base than they would be in a single‐stock model. The model's time step is flexible and can be changed during the period being modelled to accommodate better data quality in recent data. Other options include the capacity to estimate movements among stocks, allow density‐dependent growth, and choose among likelihood functions for the various data sets, between finite and instantaneous fishing dynamics and between two forms of selectivity curve.  相似文献   

6.
The means, variances, and three-dimensional spatial covariances of the ocean temperature and salinity anomalies in the upper 1400 m layer have been estimated using data of the Argo profiling floats from 2005 to 2007. The results of data processing suggest the continuation of general warming of the ocean waters noted in a number of papers based on earlier data. A pronounced geographical and vertical nonuniformity characterizes this warming but, as a whole, it is mostly distinct in the upper 100 m layer both in the tropics and midlatitudes. For the first time, the unique characteristics of the Argo observing system allowed us to obtain previously unfeasible estimates of the spatial statistics for salinity field. In particular, it has been demonstrated that the spatial structure of salinity anomalies is similar to those of temperature, excluding the case of the near-surface layer.  相似文献   

7.
In the North Cape area (34°26'S, 173°07'E) there appears to be a concentration of late juvenile packhorse rock lobsters, Jasus verreauxi (H. Milne Edwards'), which subsequently contributes significantly to the nearby fishery for adult J. verreauxi off Cape Reinga. Evidence for this is based on the overall smaller size and fewer mature rock lobsters at North Cape compared to areas nearby, and on the results of tagging experiments carried out during 1976–77. Rock lobsters tagged at North Cape moved 21–514 km, mainly west and south, before recapture at minimum rates of 0.03–2.00 krn.d‐1. For females at least, the movement away from North Cape usually occurs at about the time that sexual maturity is attained. Rock lobsters tagged near Cape Reinga moved 3–34 km west at minimum rates of 0.04–0.35 km.d‐1.

Although the closure of the North Cape grounds to rock lobster fishing restricts the taking of the small number of legal‐sized fish available in the area, the restriction ensures less mortality and damage to the undersized fish due to handling.  相似文献   

8.
Caribbean spiny lobster (Panulirus argus) settle preferentially in macroalgal‐covered hard‐bottom habitat, but seagrass is more prevalent in Florida (United States) and the Caribbean, so even low settlement of lobsters within seagrass could contribute substantially to recruitment if post‐settlement survival and growth were high. We tested the role of seagrass and hard‐bottom habitats for P. argus recruitment in three ways. We first explored possible density‐dependent regulation of early benthic juvenile lobster survival within cages deployed in seagrass and hard‐bottom habitats. Second, we compared settlement and survival of P. argus in both habitats, by comparing the recovery of microwire‐tagged early benthic juveniles from patches of seagrass and hard‐bottom. Finally, we assessed the relative abundance of juvenile lobsters in each habitat by deploying artificial structures in seagrass sites and compared these data with data from similar deployments of artificial structures in hard‐bottom habitat in other years. More early benthic juvenile lobsters were recovered from cages placed in hard‐bottom than in seagrass, but mortality of the early benthic life stage was high in both habitats. In regional surveys, the mean number of lobsters recovered from artificial shelters deployed within seagrass was lower than in any year that we sampled hard‐bottom, indicating that fewer lobsters reside naturally in seagrass, particularly large juveniles >40 mm carapace length. The greater abundance (and likely survival) of juvenile P. argus that we observed in hard‐bottom habitat as opposed to seagrass, combined with previous studies demonstrating that postlarval P. argus are attracted to, settle in, and metamorphose more quickly in red macroalgae, confirm that macroalgae‐dominated hard‐bottom habitat appears to be the preferred and more optimal nursery for Caribbean spiny lobster.  相似文献   

9.
In the past few decades, hydrothermal vent research has progressed immensely, resulting in higher-quality samples and long-term studies. With time, scientists are becoming more aware of the impacts of sampling on the faunal communities and are looking for less invasive ways to investigate the vent ecosystems. In this perspective, imagery analysis plays a very important role. With this study, we test which factors can be quantitatively and accurately assessed based on imagery, through comparison with faunal sampling. Twelve instrumented chains were deployed on the Atlantic Eiffel Tower hydrothermal edifice and the corresponding study sites were subsequently sampled. Discrete, quantitative samples were compared to the imagery recorded during the experiment. An observer-effect was tested, by comparing imagery data gathered by different scientists. Most factors based on image analyses concerning Bathymodiolus azoricus mussels were shown to be valid representations of the corresponding samples. Additional ecological assets, based exclusively on imagery, were included.  相似文献   

10.
Over the past six years international interest in multi-use marine spatial planning (MSP), as a practical process to launch integrated coastal management (ICM), exploded. This paper explores the extent to which existing national legal frameworks can support this process, focusing on the coastal marine environment. First the characteristics of an appropriate legal regime for multi-use MSP are explored by interrogating secondary data sourced from literature reviews and case studies. Key paradigms are distilled as a means of dissecting this complex process into a suite of characteristic determinants that disclose the underpinning environmental management approaches or principles. These criteria are then used to assess the compatibility of national legal regimes for multi-use MSP—in this instance the South African legal framework. Although multi-use MSP has not been explicitly adopted as a process within South Africa's broader ICM implementation, existing legislation does reveal support. The department responsible for the environment is viewed as the most appropriate agency to house the statutory mechanism for multi-use MSP at national and provincial levels, but delegating local multi-use MSP processes to local government agencies. The political will to deploy and dedicate duties and resources to effective implementation of multi-use MSP, however, remains critical. Finally, the approach adopted here is proposed as a means to assess the compatibility of other national legal regimes for multi-use MSP, although the suite of characteristic determinants may need to be reviewed from time to time, as new learning emerges from practice.  相似文献   

11.
In the mid 1990s, American lobster (Homarus americanus) from Canadian waters was considered overfished based on estimated levels of egg‐per‐recruit production (EPR). In 1997, the Department of Fisheries Oceans responded by adopting a goal of doubling the level of EPR from its 1996 level. In the Magdalen Islands (Quebec), results from a simulation model indicated that doubling EPR could be reached by increasing the minimum legal size (MLS) from 76 mm to 83 mm carapace length. This was done at a pace of 1 mm per year from 1997 to 2003. Following the increase of MLS, the size structure, mean size, and the abundance of ovigerous females improved significantly in the catches. However, levels of fishing effort are still very high. This could cause undesirable effects such as altering sex ratios and size structure of males, which could lead to sperm limitation, and reducing the contribution of multiple spawners to egg production, which could become an issue if egg quality is important. Consideration of these issues leads to the recommendation of a multidimensional approach to lobster conservation.  相似文献   

12.
Boretti (2012) claims that sea-level records show insufficient acceleration to support the projections of sea-level rise that are used worldwide for planning and policy-making. Unfortunately, his claim is based more on flawed qualitative reasoning than on quantitative analysis.We replicate Boretti's methodology of fitting quadratic functions to tide-gauge observations from Fremantle and Sydney, in order to estimate the sea-level acceleration. However, we also evaluate the uncertainty in these estimates (a crucial step, omitted by Boretti), and thereby show that the observed accelerations are statistically consistent with the projections of the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Our finding is the same when we repeat this analysis using two data sets which have smaller uncertainties, one from satellite altimeters and the other from a sea-level reconstruction.We therefore conclude that Boretti's claim is without foundation.  相似文献   

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