“Chance” and mixed-species associations

Summary Spatial associations between members of different animal species may arise through mutual behavioral attraction, through attraction to common resources or locations, or by chance. I outline a means of calculating the expected duration of associations based on the null hypothesis that members of different species move independently and randomly. Observed association durations can be compared to these expectations to identify those cases of association (or avoidance) that have biologically interesting causes. The method is applicable to any species in which the presence of a second species can be recorded during focal samples of an individual or a cohesive social group. The data required are readily collected in the field; I illustrate the use of the technique with data from several East African forest primates.     

Founder Effects,Inbreeding, and Loss of Genetic Diversity in Four Avian Reintroduction Programs

Abstract: The number of individuals translocated and released as part of a reintroduction is often small, as is the final established population, because the reintroduction site is typically small. Small founder and small resulting populations can result in population bottlenecks, which are associated with increased rates of inbreeding and loss of genetic diversity, both of which can affect the long‐term viability of reintroduced populations. I used information derived from pedigrees of four monogamous bird species reintroduced onto two different islands (220 and 259 ha) in New Zealand to compare the pattern of inbreeding and loss of genetic diversity among the reintroduced populations. Although reintroduced populations founded with few individuals had higher levels of inbreeding, as predicted, other factors, including biased sex ratio and skewed breeding success, contributed to high levels of inbreeding and loss of genetic diversity. Of the 10–58 individuals released, 4–25 genetic founders contributed at least one living descendent and yielded approximately 3–11 founder–genome equivalents (number of genetic founders assuming an equal contribution of offspring and no random loss of alleles across generations) after seven breeding seasons. This range is much lower than the 20 founder–genome equivalents recommended for captive‐bred populations. Although the level of inbreeding in one reintroduced population initially reached three times that of a closely related species, the long‐term estimated rate of inbreeding of this one population was approximately one‐third that of the other species due to differences in carrying capacities of the respective reintroduction sites. The increasing number of reintroductions to suitable areas that are smaller than those I examined here suggests that it might be useful to develop long‐term strategies and guidelines for reintroduction programs, which would minimize inbreeding and maintain genetic diversity.     

浅议生态城市建设的4个环节

阐述了生态城市理念的演化过程和生态城市的不同提法,针对生态城市建设中需要解决的诸多问题,提出了生态城市建设应主要抓好的4个环节:和谐是生态城市的核心,发展是生态城市的动力,绿色是生态城市的生命,文明是生态城市的精髓。     

4种农药复合污染对斑马鱼仔鱼联合毒性效应

为探明农药混合污染对斑马鱼的联合毒性效应,以斑马鱼仔鱼为研究对象,开展了氯氰菊酯、咪鲜胺、马拉硫磷和杀螟硫磷等4种农药的联合毒性效应研究。研究表明,氯氰菊酯、马拉硫磷,杀螟硫磷和咪鲜胺对斑马鱼仔鱼的96 h-LC_(50)值分别为0.12、17.88、12.39和1.45 mg·L~(-1)。根据96 h-LC_(50)值采用等毒比(1∶1)进行二元及多元联合毒性试验。二元农药混合污染(氯氰菊酯+马拉硫磷、氯氰菊酯+杀螟硫磷、氯氰菊酯+咪鲜胺和杀螟硫磷+咪鲜胺)对斑马鱼仔鱼联合作用表现协同作用。马拉硫磷+杀螟硫磷对斑马鱼仔鱼联合毒性在24 h时表现为协同作用,在其他不同时间均表现为相加作用。马拉硫磷+咪鲜胺二元农药对斑马鱼仔鱼联合毒性表现为拮抗作用。氯氰菊酯、咪鲜胺、马拉硫磷和杀螟硫磷4种农药的所有三元和四元混合污染对仔鱼联合毒性作用均表现为协同作用。研究表明,在真实的环境中,农药以混合物形式存在可能增加其对水生生物的毒性效应,给生态环境造成严重影响。     

无锡鼋头渚4种鹭类繁殖期的生态学特征研究

20 0 0年 3月～ 6月对无锡鼋头渚的鹭鸟繁殖期的种群生态特征进行了调查研究 ,结果表明 :栖息地共有鹭巢 3 64 0 0个 ,巢密度为 0 5 2个 /m2 ,平均每棵树有巢 3 3 6个 ;较早迁来的夜鹭首先占据了远离村庄及公路的相对较好的位置 ;鹭类筑巢对高大的马尾松利用率较高 ,且个体较大的鹭鸟多占据树的中上部 ,个体较小的鹭鸟则主要栖息于下部 ;夜鹭和牛背鹭平均窝卵数为 3个 /巢 ,白鹭和池鹭为 5个 /巢。     

Written Accounts of an Amazonian Landscape Over the Last 450 Years

Abstract:  Books, articles, government documents, and other written accounts of tropical biology and conservation reach a tiny fraction of their potential audience. Some texts are inaccessible because of the language in which they are written. Others are only available to subscribers of developed-world journals, or distributed narrowly within tropical countries. To examine this dysfunction in the tropical literature—and what it means for conservation—we tried to compile everything ever written on the biology and conservation of the department of Madre de Dios, Peru, in southwestern Amazonia. Our search of libraries, databases, and existing bibliographies uncovered 2,202 texts totaling roughly 80,000 pages. Texts date from 1553 to 2004, but 93% were written after 1970. Since that year the publication rate has increased steadily from fewer than 10 texts/year to nearly 3 texts/week in 2004. Roughly half of the Madre de Dios bibliography is in Spanish-language texts written by Peruvian authors and mostly inaccessible outside Peru. Most of the remaining material is English-language texts written by foreign authors and largely inaccessible in Peru. Foreign authors tended to write about ecological studies with limited relevance to on-the-ground conservation challenges, whereas Peruvian authors were more likely to make specific management recommendations. The establishment of a Web-based digital library for Neotropical nature would help make the tropical literature a more efficient resource for science and conservation. Additional recommendations include investing in syntheses, translations, popular summaries, and peer-reviewed journals in tropical countries, providing incentives for management-relevant research in tropical protected areas, and reinforcing training of scientific reading and writing in tropical universities.     

4株多环芳烃降解菌的分离及鉴定

以多环芳烃(PAHs)为筛选培养基,从石油污染土壤和石油废水中筛选到4株能够降解PAHs的高效微生物菌株,分别定名为3-28、NF、EW和EY;并对其进行了形态学观察、生理生化指标测定及分子生物学鉴定.16S rDNA序列分析显示,这4株细菌分别有581、582、1209和1230个碱基,与Microbacterium、Cellulosimicrobium、Chelatococcus和Sphingopyxis等4个属有较高的序列同源性,分别为100%、97.8%、98.2%和99.0%.结合表型特征和16S rDNA序列分析,用DNAMAN构建系统发育树,并用Bootstraping法对其评价,初步将3-28、NF、EW和EY这4株PAHs降解菌分别归属于Microbacterium sp.、Cellulosimicrobium sp.、Chelatococcus sp.和Sphingopyxis sp..图3表1参22     

Gas and Organic Matter in Last Glacial and Holocenic Sediments of Venice Lagoon

Two drills (MBM1* and MBM2) provided at “Bocca di Malamocco” gave environmental and palaeo-environmental information on sedimentation for the last 50,000 years. the MBM2 supplies textural, gas and organic matter studies of sediment and principal ion content of pore water. Two main palaeo-environments, divided in six cycles, are recognized. Marine environment characterizes the sediment above 12.80 metres below sea level (mbsl) and continental environment dominates the sediments below.

The concentration/depth profiles of dissolved ammonia, phosphates and gases are related to the occurrence of a relatively high organic content in the sediment core. Carbon dioxide to methane ratio shows a constant value below 20 mbsl, while above that level only carbon dioxide was detected. A sulphate gradient in the transition zone between the marine to fresh water interval suggests a methane oxidation. These findings indicate that diffusive transport of methane from marine sediments to the atmosphere may be considered minimal. the sedimentary cycles are related to the oxygen isotopic stages. They suggest a variable hydraulic regime occurred during the last Glacial time in the palaeo-plain corresponding to the present Venice lagoon.     

4种吸附剂对对氯苯酚的吸附性能

研究了常温（18℃）条件下粉末活性炭（PAC）、颗粒活性炭（GAC）、天然膨润土和天然海泡石4种吸附剂对对氯苯酚（4-CP）的静态吸附规律,考察了投加灭活活性污泥对吸附性能的影响。结果表明：4种吸附剂对4-CP的吸附符合Langmiur和Freundlich吸附等温式,且吻合良好;4种吸附剂对4-CP的饱和吸附量不同,大小顺序为：PAC〉GAC〉天然膨润土〉天然海泡石;灭活活性污泥与4种吸附剂共存时,降低了4种吸附剂对4-CP的吸附能力。     

四种不同生态系统的土壤解磷细菌数量及种群分布

通过分析农田、林地、草地和菜地土壤有机磷细菌和无机磷细菌的数量及种群结构,发现有机磷细菌数量比无机磷细菌多;有机磷细菌主要是芽孢杆菌属,其次是假单胞菌属;而无机磷细菌主要是假单胞菌属。菜地土壤解磷细菌的数量和种类最多。不同的细菌解磷能力差异很大,其解磷能力与培养介质的ｐＨ值有一定的关系;许多菌株在进一步的纯化过程中失去了解磷能力。     

Four challenges to an effective national nature assessment

Comprehensive biodiversity assessments play an essential role in strengthening global and national conservation strategies. The recently announced first U.S. National Nature Assessment (NNA) provides an unparalleled opportunity to comprehensively review status and trends of biodiversity at all levels. This broad context can help in the coordination of actions to conserve individual species and ecosystems. The scientific assessments that informed the Kunming–Montreal Global Biodiversity Framework adopted at the 2022 Convention on Biological Diversity (CBD) conference of parties provide models for synthesizing information on trends at multiple levels of biodiversity, including decline in abundance and distribution of species, loss of populations and genetic diversity, and degradation and loss of ecosystems and their services. The assessments then relate these trends to data on drivers of biodiversity loss and pathways to their mitigation. The U.S. NNA can augment such global analyses and avoid the pitfalls encountered by previous U.S. efforts by ensuring policy-relevant design, data accessibility, and inclusivity in process and product and by incorporating spatial data relevant to national and subnational audiences. Although the United States is not formally a CBD party, an effective NNA should take full advantage of the global context by including indicators adopted at the 2022 meeting and incorporating an independent review mechanism that supports periodic stocktaking and ratcheting up of ambition in response to identified shortfalls in stemming biodiversity loss. The challenges to design of an effective U.S. assessment are relevant globally as nations develop assessments and reporting to support the new global biodiversity framework's targets. By considering and incorporating the diverse ways in which society values and benefits from nature, such assessments can help bridge the gap between research and conservation practice and communicate the extent of the biodiversity crisis to the public, fostering broad-based support for transformative change in humanity's relationship to the natural world.