接种不同污泥源条件下厌氧氨氧化菌的特性

2组ASBR接种污泥源分别为好氧硝化污泥、好氧硝化污泥和厌氧氨氧化污泥按2：1比例}昆合的混合污泥。在相同条件下,经过驯化培养均实现了厌氧氨氧化的稳定运行。接种好氧硝化污泥的反应器的适应期为29d,经过105d的培养反应器成功启动;接种混合污泥的反应器的适应期为13d,经过49d反应器启动成功。从2组ASBR污泥中提取细菌总DNA,经过厌氧氨氧化菌特异引物Pla46rc／Amx820对污泥样品进行PCR扩增、克隆和测序等分析。实验结果表明,接种不同污泥源条件下的反应器中厌氧氨氧化菌的特性存在差异,接种污泥源为好氧硝化污泥的反应器中存在的厌氧氨氧化菌种为CandidatusKuenenia,而接种混合污泥的反应器中存在的厌氧氨氧化菌种为CandidatusAnammox—oglobus,与最初接种的混合污泥中的厌氧氨氧化菌相同。当接种污泥中存在厌氧氨氧化菌时,该菌株经过长时间的驯化可成为优势菌种,而当接种污泥中无厌氧氨氧化菌存在时,CandidatusKueneniasp．可以在反应器中占主导,具有更强的竞争优势。     

膜生物反应器中生物膜的生长特性

实验采用经甲苯培养驯化而成的单一假单胞菌菌种,通过分析平板式生物膜反应器内,不同阶段假单胞细菌生物膜干重、厚度、活性生物量和生物种群分布的变化,研究生物膜特性与降解效率之间的关系。实验结果表明,在挂膜初期生物膜迅速生长,生物量以及生物膜干重增长很快,有利于甲苯及营养物质的传输,降解效率也快速提升。随着生物膜的生长,生物量及干重也逐步增加,厚度逐渐增加使传质阻力不断增大,生物膜上层微生物的有机底物供应不足,使生物膜上层结构稀疏,最终维持一个甲苯的总传输量与生化降解量的平衡,生物量的生长与衰亡也达到动态平衡,形成了一个较高且稳定的降解效率。     

间歇运行式生物滴滤池处理油漆废气中试研究

为研究间歇运行式生物滴滤池对油漆生产厂废气净化能力,建立一座中试规模生物滴滤池（BTF）,接种降解菌群,采用8 h/d运行方式净化某油漆厂包装车间废气,并用PCR-DGGE技术揭示BTF细菌群落结构与工艺运行条件间的联系。油漆厂包装车间废气中挥发性有机物（VOCs）主要为甲苯、乙苯、混合二甲苯（间、对和邻二甲苯）,BTF对甲苯、乙苯、混合二甲苯最大去除率分别为88.8%、83.7%和86.3%。DGGE分析显示,BTF稳定运行时,主要优势菌相对丰度较为稳定（F,P>0.05）,其细菌多样性显著低于启动期（F,P>0.05）;同时,下层填料细菌多样性高于上层填料,其细菌结构变化也较上层明显;另外,提升培养液浓度至2倍和4倍对菌群结构亦无显著影响。     

曝气强度对同时硝化反硝化（SND）脱氮过程中N2O排放的影响

为了控制污水脱氮中N2O排放,在不同曝气强度下研究了好氧硝化段同时硝化反硝化（SND）系统的N2O排放特性,并采用PCR—DGGE技术分析微生物群落特征。结果发现,随着曝气强度的增强,系统总氮去除率下降,但脱氮中N2O—N所占比例则上升,实验中从低到高3个曝气强度下,总氮去除率分别为80．01％、65．28％和58．62％,脱氮中N2O—N所占的比例为1．89％、7．84％和9．20％。PCR—DGGE分析显示,和低曝气强度下相比中、高曝气强度下系统微生物群落发生明显变化,但中曝气强度和高曝气强度下系统微生物群落表现出较高相似性。这表明,不同曝气强度下系统N2O排放受到氮素转化和微生物群落变化的影响。适宜曝气强度不仅提高总氮去除率,还可有效控制N2O排放。     

Study on the Relationship between Tourist Influence and Residents＇ Sense of Community： An Empirical Study from Changdao County in Shandong Province

Residents＇ sense of community is an important prereq- uisite to promote the development of community. Tourism has sig- nificant influence on residents＇ sense of community. An empirical study from Chang...     

江苏阳澄湖螺类群落的空间分布格局

2008年1月～2009年10月对江苏阳澄湖螺类群落结构进行了季节调查研究。共采集到螺类4科5属6种,优势种为铜锈环棱螺,次优种为长角涵螺。阳澄湖螺类平均密度为220±47 ind./m2,平均生物量为2331±469 g/m2,螺类密度和生物量在年际和季节间均无明显差异,但群落结构存在显著的空间变化,密度在东湖区和中华绒螯蟹围网养殖区较大、西湖区最小,生物量围网养殖区最高、西湖区最低;铜锈环棱螺密度围网养殖区最高、西湖区最低,长角涵螺密度东湖区最高、围网养殖区次之、入湖河流及其它湖区极低。中华绒螯蟹养殖未导致围网养殖区螺类数量下降,螺类（主要是铜锈环棱螺）的投放可能是该区螺类密度、生物量及铜锈环棱螺所占比例较高的主要原因之一。逐步回归分析表明,水深是影响螺类群落整体密度和生物量空间分布差异的主要因子;典型对应分析（CCA）表明,铜锈环棱螺主要分布在叶绿素a较高的水域,而长角涵螺和纹沼螺则主要分布在透明度较大的地方     

试论宜居性城市绿地的规划与建设

在生态城市、可持续发展等社会思潮的推动下,宜居性城市已逐渐成为新的城市发展观。我国的城市绿地建设也由过去的点缀性工作上升为城市基础设施建设的重点内容。但从城市的宜居性角度分析,我国城市绿地的规划与建设主要存在定位比较模糊,重综合公园和专类公园绿地、轻社区绿地,重绿地美化亮化效果、轻绿地生态效益,重整体性评价指标、轻宜居性指标等问题。立足于城市绿地规划的宜居性导向,提出了合理定位、绿地工程与主体工程“四同时”, 按自然规律进行城市绿地的建设与管理,突出社区性绿地,推行“绿径＋缀块”的绿地网络布局,强调绿地的“可达性＋开放性＋复合性”,以及适度兼顾绿地规模等宜居性城市绿地规划与建设的策略。     

Effects of an Exotic Plant Invasion on Native Understory Plants in a Tropical Dry Forest

Abstract: The dry forests of southern India, which are endangered tropical ecosystems and among the world's most important tiger (Panthera tigris) habitats, are extensively invaded by exotic plants. Yet, experimental studies exploring the impacts of these invasions on native plants in these forests are scarce. Consequently, little is known about associated implications for the long‐term conservation of tigers and other biodiversity in these habitats. I studied the impacts of the exotic plant Lantana camara on understory vegetation in a dry‐forest tiger habitat in southern India. I compared the richness, composition, and abundance of tree seedlings, herbs, and shrubs and the abundance of grass among plots in which Lantana was cleared or left standing. These plots were distributed across two blocks—livestock free and livestock grazed. Removal of Lantana had an immediate positive effect on herb–shrub richness in the livestock‐free block, but had no effect on that of tree seedlings in either livestock block. Tree‐seedling and herb–shrub composition differed significantly between Lantana treatment and livestock block, and Lantana removal significantly decreased survival of tree seedlings. Nevertheless, the absence of trees, in any stage between seedling and adult, indicates that Lantana may stall tree regeneration. Lantana removal decreased the abundance of all understory strata, probably because forage plants beneath Lantana are less accessible to herbivores, and plants in Lantana‐free open plots experienced greater herbivory. Reduced access to forage in invaded habitats could negatively affect ungulate populations and ultimately compromise the ability of these forests to sustain prey‐dependent large carnivores. Additional research focused on understanding and mitigating threats posed by exotic plants may be crucial to the long‐term protection of these forests as viable tiger habitats.     

Hunter Reporting of Catch per Unit Effort as a Monitoring Tool in a Bushmeat‐Harvesting System

Abstract: Growing threats to biodiversity in the tropics mean there is an increasing need for effective monitoring that balances scientific rigor with practical feasibility. Alternatives to professional techniques are emerging that are based on the involvement of local people. Such locally based monitoring methods may be more sustainable over time, allow greater spatial coverage and quicker management decisions, lead to increased compliance, and help encourage attitude shifts toward more environmentally sustainable practices. Nevertheless, few studies have yet compared the findings or cost‐effectiveness of locally based methods with professional techniques or investigated the power of locally based methods to detect trends. We gathered data on bushmeat‐hunting catch and effort using a professional technique (accompanying hunters on hunting trips) and two locally based methods in which data were collected by hunters (hunting camp diaries and weekly hunter interviews) in a 15‐month study in Equatorial Guinea. Catch and effort results from locally based methods were strongly correlated with those of the professional technique and the spatial locations of hunting trips reported in the locally based methods accurately reflected those recorded with the professional technique. We used power simulations of catch and effort data to show that locally based methods can reliably detect meaningful levels of change (20% change with 80% power at significance level [α]= 0.05) in multispecies catch per unit effort. Locally based methods were the most cost‐effective for monitoring. Hunter interviews collected catch and effort data on 240% more hunts per person hour and 94% more hunts per unit cost, spent on monitoring, than the professional technique. Our results suggest that locally based monitoring can offer an accurate, cost‐effective, and sufficiently powerful method to monitor the status of natural resources. To establish such a system in Equatorial Guinea, the current lack of national and local capacity for monitoring and management must be addressed.     

Perspectives on utilising Community Land Trusts as a vehicle for affordable housing provision

With lack of affordable housing being clearly identified as a social and economic exclusion issue for most communities, innovative ways of addressing this deficiency should be considered. Increasingly local communities are engaging with the possibility of direct provision themselves and discussion around this notion has profound implications for community cohesion. One community-based solution gaining popular support within communities, and with government ministers, is the Community Land Trust mechanism. This involves control and ownership of land to help ensure affordable housing is built and remains affordable in perpetuity for the community. The language and difficulties with definition of terms, together with the complexity of engaging relevant stakeholders in a changing policy and legislative framework can be problematic. This may lead to apparent lack of consensus within communities on the way forward. Perceptions of local housing issues and ways to address them are sometimes vague, sometimes diverse but rarely apathetic. This paper includes data from two case studies in North East England, which are examined using interviews with key players, as a means of seeking some practical solutions.