生态系统服务研究的问题与展望

生态系统服务的研究是当前资源经济学和生态经济学的研究热点之一。通过分析生态系统服务的概念辨析,认为从生态系统功能的定义过渡到生态系统服务定义的过程中,在关注生态系统整体性的同时忽略了生态系统要素之间的相互作用,导致生态系统服务的评估中可能存在着重复估值或者估值不全面等风险。针对目前的很多生态系统的评估对生态系统的耗损贬值和环境退化所造成的负效益的忽略,以及对人类活动的干扰和气候变化等对生态系统服务产生影响研究不足,提出在今后的研究中应该在深入理解生态系统的复杂生态学机制的基础上,结合数学模型模拟在不确定性下的各种风险损失,加强对生态系统服务的时空动态分析,重视在气候变化、经济发展、环境污染、城市化以及人类活动的过度放牧和过度开垦引起的水土流失、环境退化、荒漠化等土地利用变化的干扰时生态系统服务的变化和反馈,更进一步分析和预测生态系统服务的损益和响应研究;通过长期的试验监测揭示生物多样性和生态系统的关系,测度出土地利用和环境变化对生物多样性的影响和边际效益,及其对生态系统服务的影响的弹性值,实现生态系统服务的精确估值;关注生态系统服务对人类福利的影响,尤其重视贫困地区和生态脆弱区的生态系统服务对减小贫困的研究,建立科学的生态补偿机制,实现可持续发展。     

铝与土壤之间的表面化学反应及其后果

80年代以来，由于酸雨的发生及其对农业生产和生态环境的危害，土壤酸化问题再次成为土壤化学研究的热点．铝离子的土壤化学行为是土壤酸化的根本原因，而铝的吸附是给离子的土壤化学行为的重要方面．因此．研究铝的吸附有助于提示土壤酸化的本质，为防治土壤酸化提供有益的信息．本文综述了近30年来铝离子吸附的研究进展．其中包括吸附性铝离子的形态；铝的吸附表面；阴离子对铝吸附的影响；铝吸附的机理；铝的吸附对土壤性质的影响等．     

从接受主体看文学价值的永恒性

价值是客体的属性对主体需要的满足.主体需要是在实践中产生的,是价值关系的主动条件.文学作品的价值就是文学作品的属性满足接受主体的精神需要.人类的自由需求是共同的,而美是自由的感性显现.文学作品的价值永恒性就是其审美属性满足主体需要---人的共同自由需求.     

产品的生命周期和环境:从产业生态学到家庭生态学

与人口变化相关的生活水平的提高表现为对商品和服务日益增长的需求 .生态系统恶化的原因与对原料总是更多的攫取、与小生态环境的改变、与对包括人类在内的生物群落有损害的产品日益增加的排放有关 .旨在降低环境风险的解决办法基于对社会生态学机制的更好理解,基于制定评价的工具和方法以及有效的介入 .与在企业中的环境管理举措相补充,家庭生态学能够提供有助于决策的恰当的整体的要素 .     

北京地区农业生态系统的评价与调控问题

农业生产是在农业生态系统中进行的,其生态系统的状况与农业生产的发展,尤其是持续的发展有着十分密切的关系。对农业生态系统进行确切的评价,需要掌握生态系统的特征、结构与功能以及发展的趋势,揭示其中存在的矛盾和问题,得出控制与调整结构的客观依据。评价的标准必须符合生态经济的要求,在充分利用自然资源的同时,     

发刊词

适宜的环境是人类生存发展的基础资源,经济建设和文化建设的必要条件,不言而喻,没有辽阔肥美的土地、繁茂的森林、清彻的水体、洁净的空气,就没有健全的发展,也没有子孙后代的幸福。因此,保护环境,使我们的生存空间和基础资源免受污染和破坏,是我们大家的神圣职责和不可推卸的光荣义务。     

捷克共和国

持续的清洁生产要求改变管理的理念和战略本文涉及在中等规模的电镀车间实施清洁生产的方法,在这样的车间中,捷克清洁生产中心进行过在职的培训．金属精加工领域清洁生产的潜力是众所周知的,比如通过良好的内部管理和简单的操作变化就可以。通过改善雇员的健康和安全状况还可以获得明显的效益．     

能源在可持续发展中的作用：拉丁美洲能源政策分析的要素

与能源政策和可持续发展之间的关系有关的决策的制定应该不仅包括对当前问题的鉴定和对未来影响的评估，而且为了增加这些政策成功的可能性还包括有关各方面的积极参与，因为一切环境政策都有着非常复杂的环境内涵，仅仅采用有限的技术手段或系统的运作可能很难找到合适的解决方案。     

生态危机的社会伦理根源

从人与自然的关系实际上是人与人之间的利益关系的论点出发,揭示了生态危机发生实质是人类为了获取自身利益的最大化,对自然资源无止境的索取和争夺而导致的;论证了生态危机发生的社会伦理根源是技术理性的扩张导致科学技术的异化、消费主义的盛行加重了对自然的消耗与污染、功利主义的漫延导致代际自然资源分配不公;提出了要缓解人与自然日趋紧张的关系,解决生态危机,不仅要依靠科技、经济手段,最根本的还是要从改变人们的社会伦理观出发,用价值理性自觉地调适技术理性的非理性倾向、改变物质主义的生活方式、摒弃发展理念的功利主义,从而调节好人与人之间的利益冲突,处理好人与自然的"物质变换"关系。     

植物多样性对土壤微生物的影响

生物多样性强烈地影响生态系统的过程.生态系统过程的变化可导致生物多样性衰减并因此导致生态系统功能衰退.植物种丰度和植物功能多样性对土壤细菌群落的代谢活性和代谢多样性有成正比的影响.土壤细菌的代谢活性和代谢多样性随植物种数量的对数和植物功能组的数量而直线上升.其原因可能是由植被流入土壤的物质和能量的多样性和数量的增加,也可能是由土壤动物区系起作用的土壤微生境的多样性的增加造成的.由于植物多样性的丧失所引起的植物生物量的减少对分解者群落有强烈的影响微生物生物量将可能减少,因为在大多数陆地生态系统中,有机碳源限制着土壤微生物的活性.     

On the behaviour of the residence time at the bottom of the mixed layer

To understand why the findings of Deleersnijder et al. [(2006), Environ Fluid Mech 6: 25–42]—the residence time in the mixed layer in not necessarily zero at the pycnocline—are consistent with those of Delhez and Deleersnijder [(2006), Ocean Dyn 56:139–150]—the residence time in a control domain vanishes at the open boundaries of this control domain—, it is necessary to consider a control domain that includes part of the pycnocline, in which the eddy diffusivity is assumed to be zero. Then, depending on the behaviour of the eddy diffusivity near the bottom of the mixed layer, the residence time may be seen to exhibit a discontinuity at the interface between the mixed layer and the pycnocline. If such a discontinuity exists, the residence time is non-zero in the former and zero in the latter. This is illustrated by analytical solutions obtained under the assumption that the eddy diffusivity is constant in the mixed layer.     

知识型员工的特点、激励及管理对策研究

知识经济时代，企业最宝贵的财富是知识型员工。知识型员工是生产力的代表。知识型员工的工作效率决定了企业的竞争能力．因此。如何激励知识型员工成为企业探讨的一个重要问题．本文从知识型员工的特点入手。按有关知识管理专家提出的激励因素，从四个方面阐述了对知识型员工的激励策略。并提出了对知识型员工的管理对策．     

高产玉米因土高效施肥技术研究

通过田间试验,研究广东省粤东河源灯塔盆地的粉砂坭地和粤北阳山县石灰岩山区的黄泥地氮、磷、钾养分的供应特性;高产玉米不同生育期吸收氮、磷、钾的规律,以及在不同土壤上氮、磷、钾肥的不同配比对玉米产量和经济效益的影响。根据试验结果进行统计,提出了高产玉米因土高效施肥技术方法。     

Adjusting the economy to the new energy realities of the second half of the age of oil

Our research indicates that, due to the depletion of conventional, and hence cheap, crude oil supplies (i.e. peak oil), increasing the supply of oil in the future would require exploiting lower quality resources (i.e. expensive), and thus will most likely occur only at high prices. This situation creates a system of feedbacks where economic growth, which requires more oil, would require high oil prices that will undermine that economic growth. We conclude that the economic growth of the past 40 years is unlikely to continue unless there is some remarkable change in how we manage our economy.     

Beliefs about the environment: moving from the egocentric towards the ecocentric perspective

Our behaviour towards the environment depends on our beliefs about the environment. Beliefs, however, are a subject of change, particularly during important life transitions such as the transition to adolescence, because this is a period when an individual develops the ability of complex and abstract reasoning. Understanding this transition is therefore crucial for understanding and predicting the attitudes and courses of action in terms of sustainable development later in life. Due to many methodological constraints, the number of empirical studies examining these issues is very limited; the current study aimed to collect empirical data to explore the origins of our beliefs about the environment-related issues. We devised a picture association test and used it to compare children’s and adolescents’ beliefs about our environment in the context of the means of transportation. A large sample of 2264 participants aged 6–18 years took part in the study. The data supported the claim that children’s beliefs about environment share egocentric properties. The findings represent an important puzzle into the whole picture of children’s thinking and offer us great insight into the origins of beliefs about environment-related questions in adults. Educational implications are addressed.     

关于《湿地公约》中"湿地"定义的汉译

湿地公约文本使用的英语是英国英语，其使用的词汇与美国英语有微妙的区别，湿地国际(中国)官方文本对《湿地公约》中湿地定义的汉译不确切。文章讨论了英国英语和美国英语中与湿地有关的几个词语在含义上的差别，重译并解剖了几个典型的湿地定义。     

Explaining the fragmentation in the Brazilian Amazonian forest

Although vast literature exists on the drivers of tropical deforestation and its ecological consequences, less is known about how patterns of forest fragmentation emerge in the first place. The purpose of this paper is to address this issue for the Brazilian portion of the Amazon basin by analyzing the social processes generative of five specific patterns, including rectangular, fishbone, radial, dendritic, and what we refer to as ‘the stem of the rose.’ We argue that forest fragmentation patterns in the Brazilian Amazon are largely determined by the types and arrival times of the agents who engage in land clearing. We also argue that the patterns manifest in the landscape by virtue of road construction and agricultural property formation, which often occur in tandem. We conclude by placing our discussion within legal and institutional contexts, and observe that fragmentation stemming from formal colonization projects is more consistent with biodiversity conservation than that associated with a laissez-faire occupation. However, erosive impacts may be greater in topographically sensitive areas.     

Splitting the tail of the displacement kernel shows the unimportance of kurtosis

Animals disperse in space through different movement behaviors, resulting in different displacement distances. This is often described with a displacement kernel where the long-distance dispersers are within the tail of the kernel. A displacement with a large proportion of long-distance dispersers may have impact on different aspects of spatial ecology such as invasion speed, population persistence, and distribution. It is, however, unclear whether the kurtosis of the kernel plays a major role since a fatter tail also influences the variance of the kernel. We modeled displacement in landscapes with different amounts and configurations of habitats and handled kurtosis and variance separately to study how these affected population distribution and transition time. We conclude that kurtosis is not important for any of these aspects of spatial ecology. The variance of the kernel, on the other hand, was of great importance to both population distribution and transition time. We argue that separating variance and kurtosis can cast new light on the way in which long-distance dispersers are important in ecological processes. Consequences for empirical studies are discussed.     

Dynamic preservation of the coastline in the Netherlands

In 1990, the Government and Parliament of the Netherlands decided on a new national policy for coastal defence. To ensure the enduring safety of the low-lying polders as well as the sustainable preservation of the coastal dunes, it was decided to maintain the coastline in its 1990 position. The main method for coastline preservation in the Netherlands is beach nourishment. Since 1991, approximately 7 million m³ of sand is added to the Dutch beaches annually. From an evaluation study of sand nourishment projects it is concluded that nourishment is an effective and efficient method to preserve the coastline. The evaluation study also proves that nourishment projects should be ‘tailor-made’, taking the local morphological and hydraulic conditions into account. The first results of an experimental shoreface nourishment are discussed. The choice for nourishment as the principal method to combat erosion is well in line with the intention to restore the natural dynamics of the dune-coast in the Netherlands. The key probably is a less strict policy with regard to the maintenance of the foredunes. Plans for the development of typical coastal features such as slufters^*, wash-overs, blow-outs and mobile dunes are currently under discussion. A slufter is a breakthrough in the first dune-ridge whereby the sea invades former dune slacks or beach plains situated behind the duneridge. In this way a tidal marsh is formed within the dune zone.     

水上公园水体的水供现状及营养功能状态评价

本文论述了天津市水上公园水体的水质现状,并依据有关标准对水体的营养状态,水体的游览景 产养殖,饮水备用水源等功能进行了评价。