城市化对杭州市鸟类营巢集团的影响

为了了解城市化对鸟类营巢集团的影响,2007年3月至2007年8月,沿城市化梯度在杭州地区的城区、城乡结合区、农田区、农林交错区和自然林区等类型栖息地内设置3 000 m长、100 m宽的样线各18条,共计90条;并对其鸟类物种与群落营巢集团进行调查。调查共记录到繁殖鸟类96种,根据鸟类营巢位置可将其分为林冠枝干营巢集团、灌草丛营巢集团、林冠枝干/灌草丛营巢集团、自然洞穴营巢集团、人工建筑营巢集团、自然洞穴/人工建筑营巢集团地面营巢集团、水面营巢集团和寄生集团共9种。进一步分析显示,随城市化程度提高,鸟类营巢集团的数目呈整体下降趋势,而各集团的物种数也基本呈下降趋势。但是,不同的营巢集团对城市化的反应存在差异,导致其物种组成在群落中比例的明显变化。城市化程度的提高使树冠筑巢鸟、灌丛筑巢鸟、地面筑巢鸟及自然洞穴筑巢鸟在群落中所占的比例明显下降,其中地面筑巢鸟最为敏感,灌丛筑巢鸟次之。同时,自然洞穴/人工建筑集团的鸟类在群落中的比例却随着城市化程度的提高明显上升。各营巢集团之所以对城市化做出不同反应,是因为它们对筑巢地资源利用方式不同。此外,还发现植被盖度、人工设施面积、至市中心距离以及人为干扰等因素均可对鸟类营巢集团结构产生影响,但不同类型的营巢集团对上述因素的反应各异。     

Relative influence of habitat heterogeneity, climate, human disturbance, and spatial structure on vertebrate species richness in Spain

Many factors affect the distribution of species richness. This study examines the relative influence of habitat heterogeneity, climate, human disturbance, and spatial structure on the species-richness distribution of terrestrial vertebrates (amphibians, reptiles, birds and mammals) in mainland Spain. The results indicate that spatial structure and environment exert similar influences on species richness. For all four taxa, species richness increases southward and northward, being lower in the center of the country, when controlled for other variables. This may be the result of a peninsular effect, as found in other studies, and reflect the importance of historical events on species richness in the Iberian Peninsula. Climate is more important than habitat heterogeneity in determining species richness. Temperature is positively correlated with amphibian, reptile, and bird species richness, while mammalian species richness is highest at intermediate temperatures. This effect is stronger in ectotherms than among endotherms, perhaps reflecting physiological differences. Precipitation positively correlates with bird and mammalian species richness, but has no effect on ectotherm species richness. Amphibian species richness increases with altitudinal range, and bird species richness with habitat diversity. Human population density is positively correlated with bird and mammalian species richness, but does not affect ectotherm species richness, while amphibian and bird species richness is highest at moderate levels of human land alteration (farmland). However, unexplained variance remains, and we discuss that the effects of environmental variables on species richness may vary geographically, causing different effects to be obscured on a national scale, diminishing the explanatory power of environmental variables.     

Landscape effects on birds in urban woodlands: an analysis of 34 Swedish cities

Aim To compare bird abundances in woodlands along gradients from the city centre to the peri‐urban area. To evaluate the importance of the proportion of woodland within the city and in the peri‐urban landscape to forest bird communities breeding in urban woodlands. To test whether fragmentation effects on birds were linked to the type of peri‐urban matrix. Location A total of 34 Swedish cities with > 10,000 inhabitants in south‐central Sweden. The study area covered 105,000 km², in which 84% of the Swedish population of 9.1 million lives. Methods Repeated point count surveys were conducted in 2004 in a total of 474 woodlands. General linear models were used to test for possible differences in abundance along urban to peri‐urban gradients, and to regress bird abundances in local urban woodlands on: (1) total woodland cover in the city, (2) total woodland cover in the peri‐urban landscape, (3) the interaction between woodland cover in the city and in the peri‐urban area, (4) region, and (5) human density. Results More than 12,000 individuals of 100 forest bird species were recorded. Of the 34 most common species detected, 13 bird species had higher abundances in urban than in peri‐urban woodlands, and seven species showed the opposite trend. The bird community of urban woodlands was characterized by species associated with deciduous forests and tree nesters, whereas the bird community of peri‐urban woodlands was characterized by species associated with coniferous woodland and ground nesters. Twelve species were significantly linearly associated with the proportion of urban woodland and/or the proportion of peri‐urban woodland, and a further eight species were associated with the interaction between these two factors. Local breeding bird abundances of four species were significantly positively associated with the proportion of urban woodland only in farmland‐dominated landscapes. Main conclusions Fragmentation effects on some urban birds are linked to the type of peri‐urban matrix. In farmland landscapes, peri‐urban woodlands may have been too scarce to act as a source of bird immigrants to fragmented urban woodlands. To maintain populations of specialized forest birds within cities in landscapes dominated by agriculture, it is of paramount importance to conserve any remaining urban woodlands.     

Phylogeny of magpie‐robins and shamas (Aves: Turdidae: Copsychus and Trichixos): implications for island biogeography in Southeast Asia

Aim Magpie‐robins and shamas are forest and woodland birds of south Asia. There are two genera: Trichixos for the monotypic T. pyrrhopygus, and Copsychus for other species. Two species are widespread, whereas the others are restricted to specific islands. Endemicity is highest in the Philippines. Using phylogenetic methods, we examined how this group came to its unusual distribution. Location Mainland Asia from India to southern China, and islands from Madagascar to the Philippines. Particular emphasis is placed on the Greater Sundas and Philippines. Methods The phylogeny was estimated from DNA sequences of 14 ingroup taxa representing all nine currently recognized Copsychus and Trichixos species. The entire mitochondrial ND2 gene and portions of nuclear myoglobin intron 2 (Myo2) and transforming growth factor beta 2 intron 5 (TGFβ2‐5) were sequenced for all but two species. The phylogeny was reconstructed using maximum likelihood and Bayesian methods. The timing of divergence events was estimated using a relaxed molecular clock approach, and ancestral areas were examined using stochastic modelling. Results The group comprises three main clades corresponding to ecological types: Trichixos, a primary‐forest specialist; Copsychus magpie‐robins, open‐woodland and coastal species; and Copsychus shamas, thick‐forest species. Trichixos appears to be sister to the magpie‐robins, rendering Copsychus polyphyletic. The dating of phylogenetic nodes was too ambiguous to provide substantial insight into specific geographical events responsible for divergence within the group. Some patterns are nevertheless clear. Copsychus shamas reached the Philippines, probably in two separate invasions, and split into endemic species. Copsychus malabaricus and C. saularis expanded widely in the Greater Sundas and mainland Southeast Asia without species‐level diversification. Main conclusions Magpie‐robins are excellent dispersers and have diversified into distinct species only on isolated oceanic islands. Trichixos, a poor disperser, is restricted to mature forests of the Malay Peninsula, Sumatra and Borneo. Copsychus shamas are intermediate in habitat preference and dispersal capabilities. Their endemism in the Philippines may be attributed to early colonization and specialization to interior forests. In the Greater Sundas, C. malabaricus and C. saularis populations split and came together on Borneo to form two separate subspecies (of each species), which now hybridize.     

闽江河口湿地生物多样性及其保护

根据闽江河口湿地比较系统的调查资料,分析了生物多样性的状况及其受人为活动影响的原因,提出了湿地生物多样性保护的对策。研究表明,闽江河口区西自闽侯竹岐,东至连江川石岛,共划分10个湿地类型,总面积约459.2km2。闽江河口众多的湿地串珠状排列,有6块面积较大的湿地,是鸟类的主要栖息、繁殖和迁徙地。闽江河口湿地的维管束植物107科337属465种,被子植物89科317属438种,大型水生无脊椎动物61种,鸟类29科118种,植被类型4种类型、18个群系和22个群丛。文中分析了环境污染、不合理开发利用、盲目围垦等人为活动对闽江口湿地生物多样性的影响,最后提出了湿地生物多样性的保护对策。     

持久性有机污染物（POPs）对鸟类的影响

持久性有机污染物(POPs)是高残留物质,进入生物体后会长期存留并产生危害。近年来,有关生物体中POPs的研究已成为环境化学、生态毒理学研究的热点之一。本文概述了持久性有机污染物(POPs)的主要类型、生态特征、来源和污染效应。介绍了POPs在鸟类体内富集的特点及其对鸟类的危害;分析了以鸟类作为环境监测指示生物时应注意的问题;对POPs的防治以及利用鹭类等水鸟监测环境污染的方法提出了建议。     

辽宁老铁山雀形目鸟类秋季迁徙初探

2000~2004年秋在辽宁旅顺老铁山自然保护区,通过鸟类环志和直接观察的方法,对该地区雀形目(Passeriformes)鸟类秋季迁徙规律进行了研究。5年共环志11 040只雀形目鸟类,发现8种保护区新记录种。结果表明,鸟类迁徙高峰大都集中在10月中下旬;气候条件与鸟类迁徙关系密切;不同年份优势种及种群数量均不同;鸟类的迁徙具有一定的顺序性和集群现象,但不同种类迁徙的种群大小又有差别;2004年雀形目鸟类的种类和数量都明显少于前4年,略有下降趋势。     

Restoration of Breeding by Snowy Plovers Following Protection from Disturbance

Promoting recreation and preserving wildlife are often dual missions for land managers, yet recreation may impact wildlife. Because individual disturbances are seemingly inconsequential, it is difficult to convince the public that there is a conservation value to restricting recreation to reduce disturbance. We studied threatened western snowy plovers (Charadrius alexandrinus nivosus) at a public beach (Sands Beach, Coal Oil Point Reserve) in Santa Barbara, California (USA) before and during a period when a barrier directed foot traffic away from a section of upper beach where snowy plovers roost. The barrier reduced disturbance rates by more than half. Snowy plovers increased in abundance (throughout the season) and their distribution contracted to within the protected area. Snowy plovers that were outside the protected area in the morning moved inside as people began using the beach. Experiments with quail eggs indicated an 8% daily risk of nest trampling outside the protected area. Before protection, plovers did not breed at Coal Oil Point. During protection, snowy plovers bred in increasing numbers each year and had high success at fledging young. These results demonstrate how recreational disturbance can degrade habitat for shorebirds and that protecting quality habitat may have large benefits for wildlife and small impacts to recreation.