广西大明山自然保护区两栖动物资源调查报告

2000年9月11日至26日，在广西省大明山自然保护区共采集鉴定两栖类动物66只(种)，共计9种，隶属1目，4科．结合以往的调查资料，目前已知大明山自然保护区有两栖动物动物22种，隶属1目，5科，9属．保护区内的两栖类多样性系数(H′)为1．21028，均匀度指数(J)为0．58202．     

Portuguese coastal zones and the new coastal management plans

Coastal zones in Portugal, as interface areas between land and sea, have problems related to the growing human pressure in terms of changes in land use associated with urban and industrial occupation, new accessibility (ports, motorways) and traffic flows, intensification of recreational use (beaches, water sports) and excessive fishing. Impacts include deterioration of water quality and sediments; alteration and degradation of natural habitats; new hydrodynamic situations; major landscape changes: and rapid changes in habits and way of life of the local populations and increased exposure of populations and assets to natural and induced risks (storms, accidents, spills, explosions). Plans for the Management of the Coastal Zone (POOC) have been developed and seven of them have been approved, while two similar plans are at a final stage of preparation. Together they cover the entire coast of Portugal. Their implementation and assessment could be a first step towards an integrated management of the Portuguese coastal zones. River Basin Management Plans (PBH) have been concluded and recently approved for the whole country. However, these plans do not consider estuarine systems and some other issues related to coastal systems. The National Water Plan (PNA) is under public presentation and discussion. Several ‘key messages’ are presented in this paper as a contribution for assessment of the proposals of this plan on issues related with coastal waters.     

Set-up costs and the existence of competitive equilibrium when extraction capacity is limited

Although set-up costs are prevalent and substantial in natural resource extraction, it is known that a Walrasian competitive equilibrium cannot exist in simple extraction models with set-up costs. This paper demonstrates that this result is sensitive to the assumption of unlimited extraction capacity and derives sufficient conditions for existence. An equilibrium exists if extraction is limited such that each firm earns sufficient surplus to cover its set-up costs or if firms choose extraction capacity subject to non-increasing returns. The resulting competitive equilibrium price either grows at the rate of interest when total extraction is below industry capacity or is constant when industry capacity is fully utilized. In the equilibrium, identical deposits are opened simultaneously, and set-up costs for new deposits are incurred when the industry has excess capacity rather than when capacity is fully utilized.     

海洋病毒--一种新的、潜力巨大的赤潮防治工具

概述了海洋病毒尤其是藻类病毒(包括原核藻类病毒和真核藻类病毒)的研究进展,以及赤潮发生的新态势和目前赤潮防治方法的不足,评析了海洋病毒与赤潮生物的关系,介绍了藻类病毒在赤潮控制方面所取得的一些成果,强调了海洋病毒在生态环境中的重要作用,提出了利用病毒防治赤潮的可能性及有效性,展望了以病毒调控赤潮的前景.参54     

导游人力资源的现状分析与对策

随着导游职业的社会化，导游数量急剧上升，但导游质量却是年年下降，本文就目前我国导游人力资源的学历、等级等现状为主，分析其现状和所存在的问题，并提出相应的对策与建议。     

嗜盐光合细菌的分离鉴定及其营养成分分析

从大连海岸的海泥中分离到 4株海洋光合细菌 :菌株C4 10、菌株DS2、菌株E3 和E4,它们都能在厌氧光照下营光异养生长 ,菌株C4 10还能够利用还原性硫化物营光自养生长 .依菌对NaCl的需求 ,菌株C4 10、DS2归属于嗜盐光合细菌 ,菌株E3 和E4属于耐盐光合细菌 .根据形态和培养特征、生理生化特征、光合作用内膜结构、泛醌组成、(G +C)的摩尔百分比等指标 ,菌株C4 10鉴定为Rhodovulumsulfidophilus (嗜硫小红卵菌 )、菌株DS2鉴定为Rhodobiummarinum (海红菌 )、菌株E3 和E4鉴定为Rhodobacterazotoformans.4株菌的营养成分分析表明 ,它们的细胞的最大生长量为 4× 10 9mL-1.粗蛋白含量占细胞干重的 5 5 %左右 ,菌株DS2高达 6 4 .2 % .4菌株所含氨基酸种类齐全 ,特别具备人和动物所必需的氨基酸 .4株菌均含有辅酶Q10和类胡萝卜素 .其中菌株C4 10的类葫萝卜素含量最高 .图 1表 6参 14     

紫外线B对海洋生态系统的影响

近年来随着臭氧损失现象日益严重，到达地球表面的紫外线B辐射不断加强，海洋生态系统受到了前所未有的威胁。UV-B的增强改变了生物体赖以生存的水体环境，影响了浮游植物对营养盐的吸收同化，抑制了浮游植物的光合作用，从而减少了海洋对CO2的吸收能力，其结果直接增加了温室效应。同时UV-B也直接影响生态系统食物链的各个营养级，伤害海洋病毒、细菌和浮游植物，降低浮游动物和仔稚鱼的成活率，进而影响到整个海洋生态系统的结构和功能。     

Sequential development and exploitation of an exhaustible resource: do monopoly rights promote conservation?

This paper explores the problem of sequential exploitation of exhaustible resources by a monopolist, when a setup cost must be incurred to access the next pool. Under certain circumstances, the monopolist will always follow a more conservationist path of extraction and delay the introduction of new resource pools compared to a social planner. However, with other forms of consumer demand, the monopolist may exhaust the resource more quickly, especially if many new options will follow. These results may apply especially to depletable resources like antibiotics or biotech products, for which significant research and development costs are required, followed by monopoly rights conferred by patents.     

长江口湿地资源生物的可持续利用

长江口湿地是我国一块重要的滨海湿地,蕴含了丰富的自然资源,这些自然资源为当地乃至更广领域的经济发展都作出了重要的贡献。本文主要探讨该湿地生态系统中六种具有代表性资源生物的利用现状。这六种资源生物是中华绒螯蟹苗、日本鳗鲡苗、缢蛏、河蚬、芦苇和海三棱草。它们在维持河口生态系统的稳定性和连续性上具有其他许多生物所不可替代的作用。目前由于种种原因,这些资源的持续发展已受到了一定的威胁,造成它们资源现存量下降的主要原因是过度捕捞、受污严重及围垦滩涂等一些因素。如何正确利用和保护这些资源已是一项急待解决的问题,针对这些问题为可持续利用它们提出了一些相应的对策和建议。