近50年来河西走廊区域生态环境变化特征与综合防治对策

近50年来,河西走廊地区在人类活动强烈作用和区域气候变化双重驱动下,区域水文与生态环境发生了一系列变化。①区域出山径流过程表现为走廊东段的石羊河流域出山流量多年变化呈显著减少趋势,河西走廊中、西段的黑河流域和疏勒河流域年均出山流量则呈现递增趋势,但下游河流水量锐减并呈现明显的人为水文过程特征,水体盐化和污染趋势加剧,其中Ⅳ～Ⅴ级污染河道长度达到208km。②南部祁连山区森林面积减少约16.5%,自20世纪90年代以来逐渐有所恢复;北部天然荒漠森林则持续衰退,天然林加速消亡,仅额济纳和民勤两地减少林地34.31×104hm₂。草地生态呈现以面积减少、草地荒漠化和载畜能力降低等为特征的持续退化趋势,河西地区总体退化草地面积达46.86%。③近50年来河西土地沙漠化发展十分强烈,其发展速度在80年代初期最高达到年递增2.15%,80年代后期至90年代,全区域土地沙漠化过程出现明显的减缓。以流域为单元,进行水资源统筹利用规划与管理,统筹兼顾不同区域经济发展与生态环境建设对水的需求,以生态系统健康发展为原则,遵循生态规律来进行土地资源的开发利用,系统开展流域为单元的生态功能保护与建设是提高区域可持续发展能力的根本途径。     

安宁工业区社会经济与环境持续发展战略规划

安宁是昆明的工业卫星城市和全省冶金、盐、磷化工业基地，限制其发展的环境因素主要是区域大气和水环境容量太小。围绕调整产业结构和工业布局等原则，将其划分为５个环境功能区和１个环境功能带。在未来发展中，走可持续发展道路，在布局上合理利用环境容量，加速城市化发展，加大环保投入，同时实施区域环境管理战略、污染防治战略、螳螂川水环境污染防治战略和区域水资源调控战略。     

中国双向式自然资源发展战略研究

本项研究系统分析了资源与经济发展的基本关系特点。提出中国持续发展的核心问题是处理资源与发展的关系 ,并认为关键是建立适应市场机制的资源供需体系。总结了中国跨世纪面临的资源四大挑战与存在的五大问题 ,概括了我国资源与发展的若干规律 ,首次提出中国存在资源国际贸易逆差 ,中国国际贸易的顺差是依靠资源国际贸易的逆差、牺牲紧缺资源而换取的。因此 ,中国应该实行双向式自然资源发展战略。并提出了该战略的核心思想及若干政策性建议     

康洁生产——高技术污染下清洁生产的新视点

清洁生产自80年代末在美国等发达国家提出以后。得到国际社会的普遍响应，成为一种环保潮流，被认为是环境战略由被动反应转向主动行动的一个转折点，当今高技术污染呈现许多新的特点。对清洁生产理念提出挑战。文章从清洁生产的起源和发展出发。通过反思高技术污染对清洁生产的挑战，指出了“清洁生产”需要理论完善，提出了“康洁生产”这一环境战略的新观念。     

试论西藏一江两河地区综合防护林体系建设

本文通过林业建设环境分析、论证,提出一江两河地区综合防护林体系建设的战略构想:在认真保护、科学经营现有森林资源的基础上,以拉萨河、雅鲁藏布江中段、年楚河谷地为主线,重点建设沿江防护林带,构成防护林体系的主要骨架;在河谷农田草场加速防护林网建设,完成防护林体系的网络结构;依土地条件积极营造薪炭林,适当发展用材林和四旁植树(含林卡和经济果树等),完善防护林体系的带网片结,建立起我国高原最大的综合防护林体系,保护好地理环境独特的高寒农业区和“世界第三极”。     

盘锦市危险废物现状及管理对策的初探

以盘锦市2002年危险废物申报登记的结果为依据，进行了危险废物统计分析，找出盘锦市重点危险废物是含铅废物，其主要集中在八家石油、天然气开采企业、占产生危险废物总量的70％以上。并提出了危险废物的管理对策和建议。     

Photochemical production of ozone and control strategy for Southern Taiwan

An observation-based method (OBM) is developed to evaluate the ozone (O₃) production efficiency (O₃ molecules produced per NO_x molecule consumed) and O₃ production rate (P(O₃)) during a field campaign in southern Taiwan. The method can also provide an estimate of the concentration of OH. A key step in the method is to use observed concentrations of two aromatic hydrocarbons, namely ethylbenzene and m,p-xylene, to estimate the degree of photochemical processing and amounts of photochemically consumed NO_x and NMHCs by OH. In addition, total oxidant (O₃+NO₂) instead of O₃ itself turns out to be very useful for representing ozone production in the OBM approach. The average O₃ production efficiency during the field campaign in Fall (2003) is found to be about 10.2±3.9. The relationship of P(O₃) with NO_x is examined and compared with a one-dimensional (1D) photochemical model. Values of P(O₃) derived from the OBM are slightly lower than those calculated in the 1D model. However, OH concentrations estimated by the OBM are about a factor of 2 lower than the 1D model. Fresh emissions, which affect the degree of photochemical processing appear to be a major cause of the underestimate. We have developed a three-dimensional (3D) OBM O₃ production diagram that resembles the EKMA ozone isopleth diagram to study the relationship of the total oxidant versus O₃ precursors. The 3D OBM O₃ production diagram suggests that reducing emissions of NMHCs are more effective in controlling O₃ than reducing NO_x. However, significant uncertainties remain in the OBM, and considerable more work is required to minimize these uncertainties before a definitive control strategy can be reached. The observation-based approach provides a good alternative to measuring peroxy radicals for evaluating the production of O₃ and formulating O₃ control strategy in urban and suburban environments.     

基于张家界市环境质量变化的生态环境建设对策

本文通过对“九五”期间张家界市的生态环境质量进行回顾性分析评价,在掌握其区域自然特征和生态环境现状的基础上,运用环境科学的基本理论分析了张家界市环境质量变化原因和趋势,指出了张家界市存在的主要生态环境问题,并提出了若干对策来引导张家界市的生态环境建设,以实现其建设生态城市的宏伟目标.     

Carotenoids in the egg yolks of collared flycatchers (<Emphasis Type="Italic">Ficedula albicollis</Emphasis>) in relation to parental quality,environmental factors and laying order

Birds may influence the fitness of their offspring by transmission of different amounts of carotenoids to their eggs. Carotenoids play crucial roles in antioxidant protection and immune defence mechanisms, but they may be available to females in limiting amounts. Therefore, their allocation to the eggs may be influenced by the female’s condition, age and environmental circumstances. Furthermore, the quality of the male parent, which affects the reproductive value of the offspring, may also influence this investment. In this correlational study, we investigated proximate and ultimate factors that may lead to variation in yolk lutein, zeaxanthin and β-carotene concentrations among and within clutches of a wild passerine, the collared flycatcher (Ficedula albicollis). We found that carotenoid concentration was positively associated with caterpillar supply at the time of egg formation, which suggests a proximate constraint of carotenoid availability on yolk composition. Neither female condition, body size, age, nor male plumage ornamentation, age and body size correlated with carotenoid deposition. Yolk β-carotene concentration was found to be positively linked to yolk testosterone concentration. We suggest that females allocated more β-carotene to their eggs to mitigate the potentially detrimental effects of elevated steroid concentration. We found that concentration of β-carotene increased with laying order. The possible function of this pattern may be to enhance the resistance to oxidative stress and pathogens of the disadvantaged last-hatching nestling, suggesting that collared flycatchers pursue a compensatory, “brood survival” strategy.     

Sexual selection and mating system in Zorotypus gurneyi Choe (Insecta: Zoraptera)

Body size is clearly an important factor influencing the outcome of agonistic contests, but is often weakly correlated with dominance ranks in Zorotypus gurneyi Choe (Insecta: Zoraptera). The study of the development and dynamics of dominance relations using artificially constructed colonies show that age, or tenure within the colony, is the prime determinant of dominance among males. Dominance hierarchies become relatively stable within 2 or 3 days and males that emerge later normally begin at the bottom of the hierarchy regardless of size. Males interact much more frequently when they are simultaneously introduced to each other than when they are allowed to emerge at different times. In the latter case, males that emerge late appear to recognize relative dominance of older males and avoid direct contests. Considering the high correlation between dominance rank and mating success, there is a strong selective advantage to males that emerge earlier and such pressure of sexual selection may be responsible for the difference in life history strategies between Z. gurneyi and its sympatric congener, Z. barberi Gurney, in central Panama.