Urban Domestic Gardens: The Effects of Human Interventions on Garden Composition

Private domestic gardens contribute substantially to the biodiversity of urban areas and benefit human health and well-being. We previously reported a study of 267 gardens across five cities in the United Kingdom in which variation in geographical and climatic factors had little bearing on the richness, diversity and composition of plant species. We therefore hypothesise that garden management is an important factor in determining garden characteristics. Here, from the same sample of gardens, we investigate potential associations between the uses to which people put their gardens, the types of management activities they undertake, and the characteristics of those gardens. Householders (n = 265) completed a questionnaire detailing various aspects of garden use and management activities. The majority of respondents used their gardens chiefly for relaxation, recreation, and eating. Fewer than one fifth included “gardening” amongst their garden uses even though all performed some garden management, suggesting that not all management activity resulted from an interest in gardening. Garden-watering and lawn-mowing were the most prevalent activities and were predictors of other types of management including weeding, vegetation-cutting, leaf-collection, and dead-heading flowers. A number of these activities were associated with one another, the richness and composition of plant species, and the number of land uses in gardens. However, relationships between management activities and the amount of tall vegetation were less consistent, and garden management appeared to be independent of garden area. More species of amphibians, birds, and mammals were observed in gardens with ponds and in which efforts were made to attract wildlife, particularly by providing drinking water. This study supports the hypothesis that garden use and management is associated with garden characteristics.     

Special Issue: Statistical mathematics for ecological and environmental data

Environmental and Ecological Statistics -     

清洁生产观点2:把清洁生产纳入可持续性战略

清洁生产已经作为一套手段、一个计划和一种思维方式而产生了影响.对这些影响可以从不同的层面进行评价.清洁生产虽然在过去十年取得了进步，但是仍需解决的清洁生产问题包括政府的政策、环境技术、废物减少、工作场所的安全、经济发展和社会消费.下一个十年需要取得进展的三个环境目标是去除毒性、非物质化和脱碳.另外还提出了清洁生产的一些更长期的目标.     

Heterotrophic bacterial activities and treatment performance of surface flow constructed wetlands receiving woodwaste leachate.

Heterotrophic activities were investigated by measuring 3H-leucine incorporation to bacterial protein and 14C-glucose turnover in surface flow constructed wetlands receiving woodwaste leachate. No significant longitudinal variation was found in heterotrophic activities of bacterioplankton. An open wetland, a vegetated wetland, and a fertilized vegetated wetland were used to examine the effects of vegetation and ammonium nitrate amendment. There was not a significant difference in treatment performance among the three wetlands, except for a significant pH increase and more efficient volatile fatty acids removal in the fertilized wetland. The fertilized wetland had the highest leucine incorporation rate and shortest glucose turnover time accompanied by the lowest glucose mineralization percentage, followed by the open wetland, then the vegetated wetland. Planktonic and sedimentary bacteria contributed to the majority of the total heterotrophic activities; epiphytic bacteria played a minor role. Heterotrophic activities were influenced by the availability of nutrient, electron acceptor, and organic substrate.     

Patterns of volatile metabolites and nonvolatile trichothecenes produced by isolates of <Emphasis Type="Italic">Stachybotrys,Fusarium, Trichoderma,Trichothecium</Emphasis> and <Emphasis Type="Italic">Memnoniella</Emphasis>

We reported previously that trichodiene, a volatile trichothecene derivative, was produced by a Stachybotrys isolate, also known to produce highly cytotoxic, non-volatile, macrocyclic trichothecenes (satrotoxins). We investigated the relationship between the production of trichodiene and various non-volatile trichothecenes for several molds. Volatile metabolites were concentrated by adsorption on Tenax TA and analyzed by GC/MS, while non-volatile metabolites were separated by HPLC, derivatized and analyzed by GC/MS. Stachybotrys chartarum isolates producing macrocyclic trichothecenes secreted significantly larger amounts of trichodiene and other sesquiterpenes than isolates which only produced simple trichothecenes. The amounts of secreted trichodiene were relatively small in all cases. With the exception of Memnoniella, which excreted small amounts of sesquiterpenes, the other isolates produced varying amounts of sesquiterpenes, including trichodiene, as well as simple tricothecenes, no detectable trichodiene, but large amounts of griseofulvin derivatives. In Stachybotrys there is apparently a correlation between trichodiene and macrocyclic trichothecene production. In the remaining isolates, there was no simple relationship between trichodiene and non-volatile trichothecene synthesis. Trichodiene is produced in larger amounts by Stachybotrys isolates, which also produce satratoxins, but it will be difficult to utilize this metabolite to detect toxic isolates in buildings due to the relatively small amounts excreted.     

水生毒理联合效应相加指数法

在水体中往往是多种污染物共存，它们彼此相互影响，产生协同、加合或拮抗作用。本文以联合效应相加指数法研究污染物对水生生物的毒性作用。     

Natural selection and the communal rearing of pups in African wild dogs (Lycaon pictus)

Summary The contributions of adult (>18 months) and yearling (10–18 months) African wild dogs (Lycaon pictus), to raising pups were quantified at eight natal dens, where pups remain for their first three months of life.Adults between 2–6 years of age did most of the hunting, and the dominant male often made the first grab at fleeing prey. Yearlings contributed to the hunting but were reluctant to tackle large prey animals. Yearlings and breeding females had prior access to food. Yearlings and adults regurgitated comparable amounts of food, but in one pack watched at a time of food shortage, the yearlings failed to regurgitate and stole food from the pups.Dominant dogs chased predators, especially spotted hyenas (Crocuta crocuta) from the area of the den more frequently than other adults or yearlings chased predators. Mothers, particularly in the first six weeks post-partum, stayed and protected the pups when the pack hunted.There is a positive, but non-significant correlation between the number of adult helpers and the number of pups raised. However, the sex ratio bias towards males at birth suggests that male helpers (which predominate) usually increase pup survivorship. The roles of direct and indirect selection in the evolution of the helping behavior are discussed. Indirect selection has probably played an important role in the unusual post-reproductive survival of males and their helping behavior.Serengeti Wildlife Research Institute contribution number 284     

Changes in singing behavior of male black-capped chickadees (Parus atricapillus) following mate removal

We removed the mates of ten male black-capped chickadees (Pares atricapillus) during the nest-building period to determine the effect of female presence on dawn singing. During the first dawn chorus following mate removal, males sang significantly longer, increased movement within their territory, and increased the percentage of their territory covered while singing. After the female was returned, these parameters returned to the pre-removal values. Males did not alter the frequency range or modal frequency of their songs when the mate was removed, nor did they change the degree of frequency shifting in the fee-bee song. We conclude that dawn singing in the black-capped chickadee acts, in part, as an intersexual signal, and that the behavior of frequency shifting in the song may be directed more toward rival males than females. Correspondence to: K. Otter