Barnacle distribution in Lough Hyne Marine Nature Reserve: a new baseline and an account of invasion by the introduced Australasian species Elminius modestus Darwin

The distribution and abundances of the following species of barnacles were established in autumn 2001 within the Lough Hyne Marine Nature Reserve: Cthamalus stellatus, Cthamalus montagui, Semibalanus balanoides, Elminius modestus, Balanus crenatus and Verruca stroemia. The results of the survey showed a clear distinction between the vertical distribution and the abundance of barnacle species inside Lough Hyne, and those sites sampled in the Rapids and outside the Lough. The Lough is now dominated by the introduced Australasian species E. modestus. This species was first recorded outside Lough Hyne in 1956. By 1988 it was found occasionally throughout the Lough, and appreciable numbers were recorded in 1990–1991. It has now replaced all other species in some parts of the North Basin. At sites subject to freshwater influence it is totally dominant, including in the highly sheltered Goleen site where intertidal barnacles have not previously been recorded. It is suggested that, once established in the North Basin, the sheltered nature of the Lough, combined with high summer temperatures and limited circulation, fostered retention of larvae and heavy spatfall of E. modestus.     

Conservation And Conflicts In The Sundarban Biosphere Reserve,India

The Sundarban Biosphere Reserve in West Bengal, India, is part of the largest mangrove forest ecosystem in the world. The reserve is a world heritage site and the last refuge for the endangered Bengal tiger at a crucial time when global climate change threatens their existence. The mangrove ecosystem and wildlife conservation have become the priority for the state government of West Bengal. However, in becoming so, the state government imposes restrictions on catching fish in the core and buffer areas of the biosphere reserve, which intensify fishermen's everyday resource‐access struggles in the mangrove forest. This paper examines the conflict between local fishermen and conservation needs, broadening the understanding of human‐environment relationships in the Sundarbans region of India.     

Multi‐basin depositional framework for moisture‐balance reconstruction during the last 1300 years at Lake Bogoria,central Kenya Rift Valley

Multi‐proxy analysis of sediment cores from five key locations in hypersaline, alkaline Lake Bogoria (central Kenya Rift Valley) has allowed reconstruction of its history of depositional and hydrological change during the past 1300 years. Analyses including organic matter and carbonate content, granulometry, mineralogical composition, charcoal counting and high‐resolution scanning of magnetic susceptibility and elemental geochemistry resulted in a detailed sedimentological and compositional characterization of lacustrine deposits in the three lake basins and on the two sills separating them. These palaeolimnological data were supplemented with information on present‐day sedimentation conditions based on seasonal sampling of settling particles and on measurement of physicochemical profiles through the water column. A new age model based on ²¹⁰Pb, ¹³⁷Cs and ¹⁴C dating captures the sediment chronology of this hydrochemically complex and geothermally fed lake. An extensive set of chronological tie points between the equivalent high‐resolution proxy time series of the five sediment sequences allowed transfer of radiometric dates between the basins, enabling interbasin comparison of sedimentation dynamics through time. The resulting reconstruction demonstrates considerable moisture‐balance variability through time, reflecting regional hydroclimate dynamics over the past 1300 years. Between ca 690 and 950 AD , the central and southern basins of Lake Bogoria were reduced to shallow and separated brine pools. In the former, occasional near‐complete desiccation triggered massive trona precipitation. Between ca 950 and 1100 AD , slightly higher water levels allowed the build‐up of high pCO ₂ leading to precipitation of nahcolite still under strongly evaporative conditions. Lake Bogoria experienced a pronounced highstand between ca 1100 and 1350 AD , only to recede again afterwards. For a substantial part of the time between ca 1350 and 1800 AD , the northern basin was probably disconnected from the united central and southern basins. Throughout the last two centuries, lake level has been relatively high compared to the rest of the past millennium. Evidence for increased terrestrial sediment supply in recent decades, due to anthropogenic soil erosion in the wider Bogoria catchment, is a reason for concern about possible adverse impacts on the unique ecosystem of Lake Bogoria.     

The Northern Myth Revisited? Aborigines,environment and agriculture in the Ord River Irrigation Scheme,Stages One and Two

Western Australia's Ord River Irrigation Scheme has been controversial since its establishment more than twenty-five years ago. A substantial expansion of the scheme, known as Ord Stage Two, is currently underway as a joint project of the Western Australian and Northern Territory governments. In this study I examine and compare Stages One and Two in the context of the significant social and economic changes that have occurred during this period, focusing on attitudes to, and conceptualisations of, nature and the human place in it. Despite a context in which consideration of both Aboriginal and environmental issues is now integrated into the development process, three colonial themes persist in the rhetoric of Stage Two. These are the empty landscape, the invisible Aborigine, and the idealisation of agricultural land use. When expressed together these three help to naturalise the development process as both inevitable and strategically implemented. The contradictions inherent in this process enhance existing doubts about the social and ecological sustainability of continuing attempts to 'develop' Australia's north.     

用插入观测法将高度计观测同化到海浪模式WAM中

本文讨论了海浪数值预报的特殊性,分析了卫星高度计观测的特征,指出了如何用插入观测法同化卫星高度计观测的有效浪高和海面风场,介绍了Ｔｈｏｍａｓ,Ｊａｎｓｓｅｎ等人和Ｌｉｏｎｅｌｌｏ等人的同化研究,并在结尾作了讨论和总结。     

大青沟国家自然保护区土地利用与覆盖变化研究

通过对"科尔沁草原大青沟自然保护区沙漠化程度图"的数字化处理以及相关社会、经济活动资料的收集整理,建立了大青沟及其附近地区土地利用与覆盖变化的地理信息系统数据库。同时,对1958年到1981年20多年间该地区土地利用与覆盖的变化进行了分析。结果显示大青沟自然保护区内天然植被得到了很大程度的恢复,面积由1958年的446hm²增加到了1981年的6094hm²。人工林面积也有所增加。与此同时,大青沟保护区周边地区由于不合理的土地利用,引起了以沙漠化发生发展为显著特征的土地退化过程。流动沙丘面积和斑块数由1958年的916hm²和70块增加到了1981年的9221hm²和300块,半流动、半固定和固定沙丘的面积逐渐减少。在可识别的16种土地类型中,其余土地类型的变化相对较小。值得注意的是该地区水体数量由1958年的50个减少到了1981年的25个左右,面积减少了71hm²。在科尔沁沙地这样一个生态环境脆弱的地区建立自然保护区,而保护区附近地区的土地则发生严重退化,无论这种现象与保护区的建立有无关系,都是值得引起注意的问题。     

Comparative review of marine mammal guidance implemented during naval exercises

This article reviews the types and effectiveness of marine mammal mitigation measures used during some naval activities worldwide. The three main standard methods used to mitigate the potential impacts of naval sonar sound on marine mammals are (1) time/area planning (of exercises/active sonar use) to avoid marine mammals; (2) implementation of operational procedures (e.g. ‘soft start’ - where sound levels are gradually increased over time); and (3) monitoring of animals for the purpose of maintaining an ‘exclusion zone’ around the sound source. Suggestions towards a minimum worldwide mitigation standard are made.     

中国荒漠类自然保护区保护成效评估指标及其应用

自然保护区的保护成效是近年来一个重要科学问题。中国荒漠类自然保护区面积比例较高,而针对其保护成效问题的研究较少。本文以中国荒漠类自然保护区为研究对象,结合国内外自然保护区保护成效的相关研究,构建了荒漠类自然保护区保护成效评估指标体系,包括5个因素层共计20个评估指标,并在安西极旱荒漠国家级自然保护区进行了示范应用。结果表明:本研究构建的指标体系能够反映荒漠类自然保护区主要保护对象的动态变化,从而为科学客观评估荒漠类自然保护区保护成效、提升管理水平提供重要参考依据。此外,通过示范评估可以看出,安西保护区在物种及珍稀濒危生物保护方面取得了一定成效,但在珍稀濒危及特有物种和生态系统服务功能等方面的科研监测尚有待加强。     

矿产储量与铀矿储量计算中几个问题的探讨

本文简要介绍了新的矿产资源 /储量概念及其分类框架 ,指出储量计算与勘查规范之间的关系 ,认为铀矿应分不同开采方法类型制定必要的勘查规范。当前急需制定可地浸开采的砂岩型铀矿勘查规范 ,以重点解决 8个方面的问题 ,使该类型铀矿储量计算有章可循。文章还重点探讨了可地浸开采的砂岩型铀矿储量计算中的工业指标、计算方法、块段划分、矿体圈定、特高值处理等问题。