沸石曝气生物滤池去除氨氮性能及生物学特征分析

天然沸石具有较大的孔隙率和比表面积,对氨氮有较强的选择性离子交换能力.运用天然沸石曝气生物滤池处理城市污水厂二级生化出水,结果表明,曝气生物滤池有良好的去除效果.在气水比为3∶1,水力负荷为1 m/h,温度＞20℃情况下,沸石曝气生物滤池对城市污水厂二级生化出水COD去除率为12.7%,NH3-N去除率为96.6%;试验系统沿程微生物活性和微生物量呈现逐渐下降趋势,而单位生物量的生物活性沿程分布则与此相反;曝气生物滤池对水中污染物的去除主要集中在底部进水端部分,当水流达到距进水端上方105 cm时,曝气生物滤池对水中NH3-N的去除率已达86.8%(占氨氮总去除率的90%),COD的去除率为13.3%(占COD总去除率的67%).     

岷山北坡高海拔区草本植物群落特征及主要植物功能群C、N、P含量分析

海拔是影响物种多样性格局的决定性因素之一,对生态系统格局与过程起着重要作用。运用回归分析、相关分析、Duncan多重比较和Pearson相关系数检验对岷山北坡高海拔2300—2900 m草本群落特征、群落初级生产力及不同植物功能群进行分析。结果表明:样地共调查出草本植物20科35属44种,菊科、百合科和蔷薇科的物种数分别占总物种数的比例为25%,14%和11%,表现出明显的优势性。草本群落的生物量均与海拔梯度的相关性不显著(P>0.05),且随海拔升高均表现出先增后减的总体趋势;植物盖度、物种丰富度、密度均与海拔表现出极显著负相关关系(P<0.001),而植物高度与海拔表现出极显著正相关关系(P<0.01)。从功能群的角度分析,随着海拔梯度的不断升高,禾本科、菊科以及杂类草3个植物功能群的叶碳含量(LCC)和根碳含量(RCC)整体呈上升趋势;叶磷含量(LPC)整体都呈下降趋势,而禾本科的根磷含量(RPC)呈上升趋势,菊科和杂类草表现出先升后降的趋势;叶氮含量(LNC)禾本科呈下降趋势,菊科呈上升趋势,杂类草呈先上升后下降的变化趋势,根氮含量(RNC)禾本科和杂类草的呈上升趋势,而菊科表现出先上升后下降的趋势。研究结果初步揭示了岷山北坡不同海拔梯度草本植物群落特征及其生物量的变化特征,以及物种多样性和主要植物功能群碳、氮、磷元素在海拔梯度上的分布差异,为今后岷山北坡草本群落分布格局和生物地球化学循环的研究提供科学依据。     

红花荷天然林群落结构特征的研究

对从化石门国家森林公园的红花荷天然林群落进行了样地群落调查，测定了该群落的11种树种的重要值，并对群落的结构和动态进行了分析。结果表明，红花荷在群落中处于主要地位，红花荷群落稳定，天然更新良好，处于旺盛生长阶段。     

Conservation Strategies for Endemic Fish Species Threatened by the Three Gorges Dam

Abstract:   The largest damming project to date, the Three Gorges Dam has been built along the Yangtze River (China), the most species-rich river in the Palearctic region. Among 162 species of fish inhabiting the main channel of the upper Yangtze, 44 are endemic and are therefore under serious threat of global extinction from the dam. Accordingly, it is urgently necessary to develop strategies to minimize the impacts of the drastic environmental changes associated with the dam. We sought to identify potential reserves for the endemic species among the 17 tributaries in the upper Yangtze, based on presence/absence data for the 44 endemic species. Potential reserves for the endemic species were identified by characterizing the distribution patterns of endemic species with an adaptive learning algorithm called a "self-organizing map" (SOM). Using this method, we also predicted occurrence probabilities of species in potential reserves based on the distribution patterns of communities. Considering both SOM model results and actual knowledge of the biology of the considered species, our results suggested that 24 species may survive in the tributaries, 14 have an uncertain future, and 6 have a high probability of becoming extinct after dam filling.     

应用假单胞菌进行防蜡作用的研究

假单胞菌L－11菌体与其胞外产物可以作为一种很好的防蜡剂，对L－11的发酵条件进行了优化，确定了最适发酵培养基的配方，发酵培养基以葡萄糖、蛋白胨为其最适碳、氮源，防蜡剂生产的发酵条件为：前16h的发酵温度为35℃，后期将温度降至20℃，发酵液的pH=4．5为发酵终点，此时发酵液在内条件下的防蜡率为78％，将上述所得菌液在大庆油田做了防蜡实验，结果表明，注入L－11的油井洗井周期有所延长，实验证明了L－11的发酵液可以作为一种经济、有效的蜡剂。     

秸秆不同还田方式下蚯蚓对旱作稻田土壤碳、氮的影响

通过两年的田间小区试验，研究了在秸秆的不同施用方式下，蚯蚓(Pheretima sp)对旱作水稻土壤中碳、氮的影响。设置5个处理：秸秆混施，秸秆深施 蚯蚓，秸秆表施，秸秆表施 蚯蚓，对照。2001年夏季播种旱稻，在4个主要生育期采集(0-20cm)土样。2002年再次播种该品种旱稻，采集成熟期(0-20cm)土壤。测定土壤碳、氮以及微生物量碳、氮。结果表明，不论采用何种秸秆还田方式，蚯蚓并不造成土壤有机碳和全氮显著耗减。蚯蚓活动对土壤氨态氮及硝态氮的影响较大；从总体上看，它促进了土壤氮的矿化。不同秸秆施用方式都影响蚯蚓对土壤微生物的作用，在表施秸秆情况下，蚯蚓对微生物量提高最显著。     

A Comparison of Logging Systems and Bat Diversity in the Neotropics

Abstract:  Evaluating logging systems to determine which are most compatible with the maintenance of biodiversity is of prime importance if tropical forests are to be managed in a sustainable way. Bats are model taxa for this purpose. Two different logging systems are used in the natural forest of the Victoria-Mayaro Forest Reserve in Trinidad: open range and periodic block. Open range is a continuous harvesting system and, in common with most methods used to log tropical forests worldwide, has few harvest controls other than girth limits for selected species. Periodic block is a polycyclic system, with felling based on ecological criteria assumed to be compatible with the maintenance of biodiversity. To compare the effects of periodic block and open-range systems on biodiversity, we determined bat species richness and abundance in each system and in primary forest. We caught bats in mist nets set at ground level and in the canopy and in harp traps. In total 1959 individuals representing 38 species were captured. Species richness was similar among primary forest and logged forest habitats, although bat diversity was lower in logged forest. The distributions of bat species abundance did not differ significantly between logged forest and primary forest. We found, however, that both logging systems lead to a decrease in gleaning animalivores and an increase in frugivores. The increase in frugivores was likely the result of an increase in the abundance of bat-dispersed pioneer fruiting plants in logged forest. Bats of periodic-block-managed forest were more similar to those of primary forest than those of forest logged using the open-range system, indicating that the periodic-block system is more compatible with the maintenance of bat diversity. Our results support the suggestion that the measured use of tropical forests can largely be compatible with biodiversity conservation.     

化学-生物絮凝污水处理工艺中微生物群落结构变化分析

利用分子生物学技术，直接从化学-生物絮凝工艺的活性污泥样品中提取DNA，对16S rDNA V3区进行PCR扩增，结合DGGE（变性浓度梯度凝胶电泳），分析了活性污泥中微生物群落结构，并对Shannon多样性指数进行分析讨论，通过研究指出系统中细菌数量的增加或减少．测定了活性污泥中部分菌种的16S rDNA V3区片段序列，通过NCBI（美国国立生物技术信息中心）基因库比对，初步确定细菌的属．结果表明，PCR—DGGE结合测序技术是一种完全可行的快速进行环境样品微生物研究的分析方法．图3表4参13     

南岳森林群落生物多样性研究(Ⅴ)上封寺森林群落植物物种多样性测定

本文根据对南岳上封寺森林群落野外实地考察以及研究结果,选用了24个有代表性的物种多样性测定公式,并采用重要值、株数或鲜重、优势度或盖度作为测度指标对南岳上封寺森林群落植物物种多样性进行了研究。结果表明,南岳上封寺森林群落植物物种多样性水平较高,但又低于南岳广济寺。此外,不同测度指标对物种多样性指数的结果并无明显的规律性变化。     

Preliminary evidence for the metabolism of benzo(a) pyrene by Plantago lanceolata

Polycyclic aromatic hydrocarbons (PAHs) have long been recognised as potential carcinogens in animals in which biotransformation into reactive metabolites can lead to DNA damage. In animals PAHs metabolism mainly occurs in hepatic microsomes and is associated with the cytochrome p-450 mediated mixed functional oxidase (MFO) system. PAH metabolism in plants has been shown to occur via a similar enzyme system, but has received relatively little attention. This study is looking at how the plant species Plantago lanceolata metabolises benzo(a)pyrene (B(a)P), which is one of the PAHs whose metabolism has been studied extensively in animals. The aim of the work is to establish firstly that the B(a)P is taken up and secondly that it is biotransformed by the plant to products possibly similar to those found in animals. This work is achieved by using C-14-B(a)P along with whole body autoradiography, scintillation analysis and chromatography techniques to locate the B(a)P and its metabolites.