Rockfish in Puget Sound: An ecological history of exploitation

In Puget Sound, WA (USA), rockfish (Sebastes spp.) have significantly declined in abundance, with multiple petitions to list individual species under the Endangered Species Act. In order to better understand the ecological legacy of rockfish fishing to the Puget Sound ecosystem, the local history of rockfish exploitation was reviewed, focusing on the socioeconomic forces and management decisions which influenced the trajectory of landings. Rockfish have always been harvested for human consumption in the region, but over time exploitation patterns have changed from an opportunistic subsistence activity by indigenous peoples, to a year-round target of commercial and recreational interests. Annual commercial and recreational harvests together peaked (almost 400 mt) in the early 1980s as anglers’ attitudes changed, gear technology improved, rockfish became more familiar to the market, human population increased, and agency programs promoted fisheries to sustain employment. Rockfishes were generally not managed intensely or with conservation goals in mind until the late 1980s, in part due to scientific shortcomings and a lack of resources. By the time management actions were deemed necessary, the greatest harvest had already occurred. However, the low intrinsic productivity of most rockfish species suggests that the legacy of fishing will remain for years to come. As managers strive to restore the integrity and resilience of Puget Sound, they must realize the significance of historical fishery removals to the ecosystem and use the proper social and economic incentives to drive individual behavior toward these ecosystem goals.     

玛纳斯河流域水资源利用及其存在的问题

新疆玛纳斯河流域平原区的水资源开发利用历史悠久。随着研究区工农业和社会经济的不断发展,灌溉工程体系日趋完善。总的水资源开发利用思路较为合理,对当地经济和生态环境的发展起着积极的推动作用,但也存在一些不合理的因素,导致了生态环境形势严峻、溢出带泉流量减少、地下水位持续下降和水质恶化等环境问题。据此,本文提出了水资源合理开发利用建议。     

湘西洛塔岩溶水的综合开发与持续利用

洛塔以屋檐洞地下河系为主,地下水资源丰富,地表水缺乏.采用修建溶洼水库、地下河出口和岩溶泉围堰、堵地下河引水的开采方法,在深埋大于200m的地下河内开凿引水隧道,引水灌溉并供人畜饮用,取得了良好的效益.通过对表层岩溶带地下水的开发,解决了分散居民长期困扰的生活用水问题.根据区内水资源分布特点,总结出高洼堵洞修建溶洼水库;斜坡谷地堵截引水;河间谷地建立梯级电站开发水能资源;发展林业,增加森林对地下水资源调蓄能力的水资源持续开发利用模式.     

Fishing selectivity as an instrument to reach management objectives in an ecosystem approach to fisheries

With the development of the ecosystem approach to fisheries, improving fishing selectivity has increasingly been put forward as an objective for management. The aim of this paper is to clarify the limits of fishing selectivity and its use in fisheries management. Fishing selectivity would be better apprehended if restricted to the catching process only, not to the utilisation that is made of the catch once onboard, which falls under catch utilisation. Confusion would be further limited if fishing selectivity is restricted to the fishing operation scale, while exploitation pattern, i.e. the distribution of fishing mortality at the population or community level, applies to larger scales. Fishing selectively is minimizing bycatch – catching primarily the fishing trip targets. Since the ecological consequences of maximising the target catch relative to bycatch remain unknown at integrated scales, fishing selectivity cannot be used as an objective in itself. However, its small scale, high manageability and good understanding make it a convenient instrument to reach management objectives at large scales. Selectivity can serve to manage what is extracted from the ecosystem and thus what can be used, and/or to manage what is left in the ecosystem and how fishing impacts it. Different factors affect fishing selectivity, catch utilisation and exploitation patterns, some of them are manageable and thus can be used to move towards these objectives. Management tools are diverse, but need to be integrated to meet large-scale objectives. The complexity of dealing with large scales incurs a need to develop the available knowledge on exploitation patterns and catch utilisation to be able to adequately manage and monitor progress toward selectivity-related objectives.     

热水井开采对怀来台流体动态的影响分析

对河北省怀来县后郝窑地热田热水井开采的情况进行了调查。 并分析了热水井开采对怀4与怀3二口井水位、 水温、 流量、 氡与汞动态的影响, 结果证明同层热水井开采对地震地下流体动态的影响是严重的。 这种影响在多年、 年、 月、 日等不同频带的各种测项的动态中和模拟与数字化不同观测方式中都有所表现, 而且开采结束之后还存在一个多月的影响时间。     

保山西邑岩溶充水矿床涌水量三维模拟研究

概化研究区合理水文地质概念模型的基础上,建立地下水三维数学模型。通过渗透试验确定出三维渗透系数,运用有限差分法对该模型进行计算,模拟出在实施不同工程条件下的矿井开采涌水量,提供经济合理的治水途径。     

论我国南海资源的特点及开发利用对策

南海我国可管辖的海域面积近 2 0 0万km2 ,具有丰富的生物、油气、矿产等资源 ,是我国经济与社会可持续发展的强大支持和保障因素 ,具有海域面积大、资源丰富、区位优势明显、未来开发潜力大等特点。应从强化“寸海寸金”的海洋国土意识出发 ,通过创新管理体制和运行机制 ,建立强有力的海上统一执法队伍 ,按照统一规划、相对集中、由远及近的原则实施重点区域开发战略 ,全面提升南海国土资源开发利用的水平和效益     

中美页岩气开发合作途径初探

中国作为世界页岩气开发的后来者,开采的资源情况、理论研究、技术开发应用、评价测试等尚处于探索起步阶段,需要借鉴国外页岩气开发的经验。美国页岩气商业化的成功,让我国看到了增加天然气自给能力的可行性,使得我国在页岩气研究与开采上有可借鉴的经验。本文根据美国页岩气开发历程与我国页岩气开发现状,列举了美国页岩气的开采技术、政策法规,并根据我国的具体现状对中美页岩气的开采技术领域、投资领域以及政策法规领域的合作模式分别进行了分析与探讨。     

甘肃省地热资源分布特征、开发现状与前景

甘肃省地热资源分布可分为隆起断裂型和沉降盆地型两类,隆起断裂型分布在北山、祁连山、西秦岭3条造山带。沉降盆地型分布在安西—敦煌盆地、河西走廊盆地群、陇中盆地群(祁连东段)和陇东盆地,祁连东段是甘肃省地热资源目前有利开发地段。