Historical abundance of juvenile commercial fish in coastal habitats: Implications for fish habitat management in Canada

An important component of science-based fisheries policy is the provision of habitat adequate for population renewal. In Canada, the Fisheries Act pays little attention to managing fish habitat, and was further weakened by changes enacted in 2012. Specifically, determining the role of fish habitat in contributing to fisheries and fish stock recovery is challenging when many stocks have severely declined and no longer occupy former habitats. This study compared the abundance of juvenile fish in coastal vegetated habitats before and after collapse or decline of groundfish stocks in Atlantic Canada. This comparison was done by compiling past studies that surveyed juvenile Atlantic cod (Gadus morhua) and pollock (Pollachius virens) in vegetated habitats across three provinces. Two studies were repeated, and one that already had post-collapse data was analyzed to quantify long-term changes in juvenile abundance. In all three cases substantial reduction in juvenile abundance coincided with declines in adult stocks. However, juvenile fish still occur in coastal habitats and could aid in adult stock recovery. The current version of the Canadian Fisheries Act requires presence of an ongoing fishery to trigger habitat protection. This is problematic as low fish abundance may lead to lowered habitat protection and potentially habitat degradation, with less or lesser-quality habitat for fish in the future. Thus, recommendations are made to repeal the 2012 Fisheries Act changes and enhance current fish habitat legislation. Using a precautionary approach for coastal fish habitat management, particularly in valuing its potential for fish stock recovery, would strengthen Canadian fisheries management.     

基于数据立方体的多最小支持度关联规则在犯罪分析中的应用

为了快速获取候选项集的支持度,避免频繁访问数据库而造成效率低下的问题,在MSapriori算法的基础上引入数据立方体,提出DC_MSapriori算法。该算法无需多次扫描事务数据库,减少了I/O操作,降低了搜索开销。实验基于福州市鼓楼区各大医院周边的案事件数据,快速挖掘出犯罪时空模式,验证了算法的有效性。     

An ecosystem approach to small-scale fisheries through participatory diagnosis in four tropical countries

Participatory diagnosis is an approach to identify, prioritize and mobilise around factors that constrain or enable effective governance and management in small-scale fisheries. Diagnostic frameworks are mostly designed and used for systematic scientific analysis or impact evaluation. Through participation they also have potential to guide contextually informed improvements to management in practice, including transitions to contemporary forms of governance like the ecosystem approach to fisheries (EAF)—the focus of our study. We document and critically reflect on participatory diagnosis processes and outcomes at sites in Indonesia, Philippines, Solomon Islands and Tanzania. These sites were part of an international project on the implementation of the EAF and differed widely in institutional and operational contexts. The Participatory Diagnosis and Adaptive Management framework and the “issue radar” diagnosis map were used to identify, evaluate and address factors associated with navigating management transitions towards the EAF. We found that many challenges and priority actions identified by participants were similar across the four study countries. Participants emphasized habitat restoration, particularly mangrove rehabilitation, and livelihood enhancement. The importance of strengthening governance entities, networks and processes (e.g., harmonization of policies, education and awareness of policies) was also a prominent outcome of the diagnosis. Site-specific factors were also explored together with the differing views among stakeholders. We conclude that diagnosis frameworks are indeed useful tools for guiding management transitions in fisheries, particularly where they enable flexibility in approaches to diagnosing problems and applying solutions to local contexts.     

Big data analytics: six techniques

Abstract

Big data have 4V characteristics of volume, variety, velocity, and veracity, which authentically calls for big data analytics. However, what are the dominant characteristics of big data analysis? Here, the analytics is related to the entire methodology rather than the individual specific analysis. In this paper, six techniques concerning big data analytics are proposed, which include: (1) Ensemble analysis related to a large volume of data, (2) Association analysis related to unknown data sampling, (3) High-dimensional analysis related to a variety of data, (4) Deep analysis related to the veracity of data, (5) Precision analysis related to the veracity of data, and (6) Divide-and-conquer analysis related to the velocity of data. The essential of big data analytics is the structural analysis of big data in an optimal criterion of physics, computation, and human cognition. Fundamentally, two theoretical challenges, ie the violation of independent and identical distribution, and the extension of general set-theory, are posed. In particular, we have illustrated three kinds of association in geographical big data, ie geometrical associations in space and time, spatiotemporal correlations in statistics, and space-time relations in semantics. Furthermore, we have illustrated three kinds of spatiotemporal data analysis, ie measurement (observation) adjustment of geometrical quantities, human spatial behavior analysis with trajectories, data assimilation of physical models and various observations, from which spatiotemporal big data analysis may be largely derived.     

基于灰色关联分析法的页岩气资源丰度敏感性研究

页岩气成藏是多种因素共同作用的结果。要探明页岩气资源丰度,就要分清各种影响因素之间的关系及其重要性。研究影响页岩气资源丰度的各种因素,从众多影响因素中分析各种因素的敏感度具有重要意义。本文介绍了页岩气成藏条件,研究了影响页岩气资源丰度的主要因素。以北美典型的页岩盆地地层与中国四川盆地下古生界页岩地层相关数据为基础,利用灰色关联分析对页岩气资源丰度各种影响因素的重要程度进行研究。该方法的思路为:首先在大量离乱、随机的统计数据中建立参考数据和比较数据;其次,由于数据的单位不同,对原始数据进行无量纲化处理,使数据具有可比性;最后,运用灰色关联分析法处理数据,从整体观念出发进行综合评价,确定其对目标要素的贡献程度。本研究得到的资源丰度敏感程度自大到小依次为页岩深度、厚度、演化度(Ro)、有机质(TOC)和孔隙度,这为以后页岩资源丰度的研究提供了理论借鉴。     

Putting the principles of the Sustainable Livelihoods Approach into fisheries development policy and practice

The Sustainable Livelihoods Approach (SLA) combines a conceptual framework with a set of operational principles to provide guidance on policy formulation and development practice. The SLA has been widely used in coastal and fisheries development research and has informed the design of development programmes but experience of operationalising it remains largely undocumented. In the Sustainable Fisheries Livelihoods Programme, which involves 25 West African countries, the SLA has helped to align fisheries policy with wider poverty reduction initiatives and to identify means of contributing to poverty reduction that do not directly increase pressure on fully or over-exploited fish resources.     

略论渔业资源学的数学化趋势

本文主要从渔业资源学中数学方法的应用起源，渔业资源评估学，数量分类学，统计生态学，种群营养动力学等数学分支在渔业资源中的应用发展及其动因分析等几个方面论述了渔业资源学的数学化趋势。     

Law and fisheries reform: Legislative and policy developments in South African fisheries over the decade 1994–2004

Following the enactment of the Constitution in 1996, the South African government undertook a process of legal reform in the fishing sector. This led to the publication of a new fisheries policy endorsing equity and sustainability, as reflected in the Marine Living Resources Act. This paper examines efforts to implement the policy, particularly the objective of “transformation”, against the background of law reform in fisheries over the last decade. The discussion is located within the context of related domestic legal developments and current trends in international fisheries law. Methods for enhancing effective implementation of the new fisheries policy are highlighted.     

Effectiveness of the structural fisheries policy in the European Union

This paper presents an analysis of the effectiveness of the community structural policy in the fisheries sector by comparing the relative level of compliance with objectives (reduction of fleets and economic viability) with the mechanisms that have been implemented (structural funds and allocation of quotas). On the one hand, this analysis shows that there is a positive correlation between the level of structural funds and the attainment of goals. On the other hand, it was found that the greater the relative availability of quotas, the poorer the countries performed in complying with the objective of reducing the fishing capacity, and the higher the expectations of achieving acceptable yields. These correlations, however, were not very strong.     

Contractual solution to the tragedy of property right in coastal fisheries

This article aims to analyze how private property regimes can co-exist with common property regimes in a coastal area. The case study shows how the dynamics of private property and common property right holders is in creating commitment to make symbiosis in resource use. This is based on a case study in two villages in West Lombok, Indonesia, where pearl-culture as a private property resource exists in a common property regime. This is a successful story in dealing with the tragedy of property rights in the country wherein established institutional arrangement is still absent. Nevertheless, this may be site specific, and fragile if there is no institutional arrangement combining formal and informal rules and involving both formal and informal authorities. To make a robust solution, multilevel solution must be considered: national, local, and community level, with reference to Japan case.