高浓度有机废水厌氧处理研究

指出了高浓度有机废水的排放给水体造成了严重的危害,对其处理的研究具有重要意义。阐述了高浓度有机废水的来源,分析了近年来比较广泛使用的厌氧处理技术,探讨了这项技术在高浓度有机污水资源化处理领域的应用前景及发展方向。     

超临界水氧化处理难降解废水的中试研究

指出了高浓度难降解有机废水对环境危害很大，此类废水采用常规技术一般无法处理或者处理效果差且运行费用高。超临界水氧化（SCWO）是一种新兴的，很有前景的处理高浓度难降解有机废水的环保技术，具有很多特色和优势。介绍了处理高浓度、难降解、小流量有机废水的超临界水氧化处理中试装置，采用该装置对造纸黑液、制药废水、化工废水和军工废水等不同种类的高浓度难降解有机废水进行了处理。最大处理量为12．5L/d ，化学需氧量（COD）的去除率＞99％，处理后的排放水质可以达到国家规定的排放标准。     

高浓度难降解制药废水强化预处理技术研究进展

指出了高浓度难降解制药废水毒性大、盐分高、成分复杂，是公认的难处理的一类废水，传统的处理方法难以处理此类废水，故需要进行强化预处理才能达到预期的处理效果。对近年来国内外处理制药废水的强化预处理技术进行了介绍与评价，对制药废水处理技术的发展方向进行了展望。     

过硫酸盐在有机污染土壤修复中的应用

指出了过硫酸盐的高级化学氧化是近年来出现的一种新兴的有机污染土壤修复技术。从过硫酸盐活化方式及在土壤和地下水修复中的应用两个方面探讨了相关研究进展,提出了实际应用中存在的问题,并对未来研究进行了展望。     

工矿企业污染场地修复工程案例分析

指出了随着我国城市化进程加速和产业结构调整,导致因城市工业企业搬迁、改造或关闭而遗留大量的污染场地。污染场地不仅会对周边环境和居民健康带来严重威胁,也制约了土地资源的安全再利用,需通过必要的工程措施进行污染修复。以某城市某片区关停企业场地修复工程为例,通过全面的污染调查与分析,提出了污染场地修复技术方案及其实施要点,以期作为工程案例为同类污染治理提供借鉴。     

南京市污染地块环境管理对策探讨

指出了为应对逐渐增多的关闭搬迁遗留地块,南京市在制定管理政策、强化多部门联动监管等方面进行了积极探索,以有效防范污染地块土壤环境安全事件发生。对南京市的管理实践进行了总结,分析了污染地块管理中存在的困难,并提出了相应的对策建议,为污染地块环境管理工作未来走向提供思路。     

水生植物氧化沟治理橡胶废水试验小结

橡胶制胶废水是一种高浓度的有机废水，其中含有橡胶粒子、酸、氨、蛋白质、糖类等多种成分。由于橡胶废水中含有大量的胶粒，在其他废水处理中一些应用较好的方法和技术用于橡胶废水处理上却不成功。近年来橡胶废水处理工艺技术有了较大发展，处理方法有稳定塘法、厌氧一机械曝气法、生物接触氧化法等。景洪农场四胶厂由于所处环境的限制，上述的方法都难于应用。为了减少污染并达标排放，胶厂的领导和技术人员因地制宜，大胆探索，于1994年初设计建成了一套以水生植物氧化沟为主的简易橡胶废水处理设施，经过几年运行，生化沟对橡胶废水的…     

植物对土壤Cd、Pb污染的修复与抗性机理研究进展

近年来,土壤重金属污染呈现扩大趋势,其中Cd、Pb污染尤为严重。重金属污染治理方法虽有很多,但各有利弊。传统的物理和化学治理方法存在花费高、操作难、容易破坏土壤理化特性和干扰土壤生物多样性等问题。近年来,植物修复技术逐渐被人们所认知和重视,它具有原位修复、廉价、对环境友好等优点。文中从重金属Cd、Pb对植物的影响、植物修复技术和植物抗性机理3个方面对国内外相关研究进展进行综述,并展望今后的发展方向,以期对未来土壤重金属污染修复技术和基础研究提供参考。     

有机固体废弃物蚯蚓堆制处理

蚯蚓能疏松土壤,增加土壤有机质并改善结构,分泌出一种能分解蛋白质、脂肪和木质纤维的特殊酚,生活垃圾、活性污泥、造纸、食品工业下脚料是其食料,因此,蚯蚓能在一定程度内清除环境污染.叙述了有机固体废弃物的污染状况以及对环境造成的压力,并从堆置处理技术、影响因素等几方面概述了蚯蚓处理有机固体废弃物的相关研究和成果进展.     

加根条件下PAHs污染土壤理化性质的动态变化

多环芳烃(PAHs)是普遍存在于环境中的持久性有机污染物,土壤理化性质影响PAHs污染土壤植物修复的效率。以菲为多环芳烃(PAHs)代表物,人工添加栾树细根,设置3个处理:1加根处理:加根、加菲;2无根处理:不加根、加菲;3对照:不加根、不加菲,研究细根添加下菲污染土壤理化性质的动态变化。结果表明:(1)菲污染土壤p H略有上升,细根添加对污染土壤p H影响不明显;(2)菲污染显著增加了土壤有机质含量,细根添加进一步增加污染土壤有机质含量;(3)菲污染显著降低了土壤全N、P含量,细根添加增加了污染土壤N、P含量,但仍低于对照。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.