Fragmentation causes rarity in common marmosets in the Atlantic forest of northeastern Brazil

The purpose of this study was to investigate the population status of the common marmosets, Callithrix jacchus, in one of their main habitats, the northeastern Atlantic forest of Brazil, where only 2% of its original area remains as small and isolated forest fragments, to determine long-term viable populations. The study was carried out in 15 forest fragments, measuring from 3,478.3 ha (the largest) to 6 ha, which were invariably subjected to high human impact. Line transect surveys were carried out between January 2002 and December 2004, along transects measuring from 350 to 4,000 m, between 0500 h and 0900 h. Common marmosets were registered in 73% (n = 11) of the forest fragments, were not recorded in the largest one, the Coimbra Forest, and group sizes varied from 1 to 4 individuals. A negative significant relationship was detected between the size of the fragment and the number of sightings of common marmosets. It is shown that the number of groups of common marmosets dwelling in this highly impacted landscape is nowadays lower than necessary for long-term survival. Additionally, smaller fragments having more groups suggests that they live in total association with humans, which assure their subsistence through the supply of introduced and exotic foods.     

The Importance of Tropical Rain Forest Fragments to the Conservation of Plant Species Diversity in Los Tuxtlas, Mexico

Of what value are forest fragments to the conservation of the tropical rain forest diversity for a landscape? We compared the changes in composition, diversity, and plant structure of 15 small (1–76 ha) relatively unprotected forest fragments with those of a large (700 ha) well protected fragment (LWPF) in Los Tuxtlas, Mexico. The trees, shrubs, lianas, palms, and herbs with dbh?≥?2.5 cm were sampled in 1000 m² at each site. For each ecological group (based on light requirements for germination: primary, secondary, and non-secondary light demanding, NSLD, species) and life form, estimates of species diversity, density, and basal area were analyzed using a stepwise multiple regression to determine whether there were any relationships between these variables and fragment characteristics (size, shape index, and isolation). The composition and plant structure of LWPF were different from those of the small fragments and large trees are absent from the canopy of the latter. Fragment size best explained the differences in composition and plant structure. Species composition in the largest fragments was similar to that of LWPF, but there was no significant difference in total richness between LWPF and the fragments, even though both the richness and abundance of secondary and NSLD species did differ. LWPF had more large primary trees in the canopy, and a greater abundance and basal area of palms and herbs. For tropical rain forest conservation, it is important to maintain the greatest possible number of large fragments and establish policies that prevent forest remnants from being further reduced in size and increasingly isolated from each other.     

Effects of fragmentation on parasite burden (nematodes) of generalist and specialist small mammal species in secondary forest fragments of the coastal Atlantic Forest,Brazil

Parasites are considered to play an important role in the regulation of wild animal populations. We investigated parasite burden of gastrointestinal nematodes and body condition in specialist and generalist small mammal species in secondary forest fragments in the highly endangered coastal Atlantic Forest. We hypothesized that body condition decreases with increasing parasite load and that parasite burden increases with increasing fragmentation in specialist species but not in generalist species as a consequence of differing responses to fragmentation effects. Investigated species were Akodon montensis, Oligoryzomys nigripes, and Delomys sublineatus (rodents) and the marsupials Marmosops incanus and Gracilinanus microtarsus. Prevalence of parasites was high in all species except for the arboreal G. microtarsus, presumably because of decreased infection probability. No correlation was found between body condition and parasite load in any of the species. Contrary to our expectations, body condition of the specialists D. sublineatus and M. incanus increased in both species with increasing fragmentation. In D. sublineatus, parasite burden increased and body condition decreased in fragments with relatively high density probably due to increased contact rates and facilitation of infection with nematodes. In all generalist species, low or no correlation between parasite burden and fragmentation was detected, suggesting little effect of fragmentation on population health.     

Plant endemism in two forests in southern Bahia, Brazil

An important factor in determining species rarity is the geographic distribution of species. Estimates were made of the level of endemism of the flora of two sites in the southern Bahian wet forest zone. Estimates were made for endemism in the Atlantic forest biome and for the much more restricted area of southern Bahia and northern Espi´rito Santo and are derived from analyses of the distributions of the species known from each area. The species checklist for each area is based on identified specimens resulting from intensive collecting in a forest near Serra Grande (40km north of Ilhe´us) and the Una Biological Reserve (40km south of Ilhe´us). Slightly less than half of the species (45.2% at Una and 47.7% at Serra Grande) have widespread distributions and 7.4% at each site are disjunct between the coastal forests and Amazonia. In the Una Reserve, 44.1% of the species are endemic to the coastal forest and 28.1% endemic to southern Bahia and northern Espi´rito Santo. At Serra Grande, 41.6% of the species are endemic to the coastal forest and 26.5% endemic to southern Bahia and northern Espi´rito Santo.     

西双版纳热带雨林树种多样性的尺度效应

基于西双版纳20hm2森林动态监测样地内直径≥1cm的树种资料,分析了该样地树种香农多样性指数和辛普森多样性指数及其方差和变异系数在7个取样尺度(5m×5m、10m×10m、20m×20m、25m×25m、50m×50m、100m×100m、200m×250m)的变化规律,结果表明:(1)香农指数-面积曲线在尺度100m×100m有一个峰值,而辛普森指数-面积曲线在尺度为20m×20m有一个峰值。(2)香农指数和辛普森指数的方差随尺度的增加而减小,其中香农指数的方差在尺度100m×100m上最小,辛普森指数在尺度20m×20m方差最小,表明香农多样性指数在100m×100m的尺度上所获得的多样性信息比较可靠,而辛普森指数在20m×20m的尺度上所获得信息比较可靠。(3)多样性指数的方差和变异系数远大于随机模型拟合的数值,说明样地内树种不是随机分布。     

Comparing bird assemblages in large and small fragments of the Atlantic Forest hotspots

The Atlantic Forest (AF) is one of the five most threatened and megadiverse world hotspots. It is arguably the most devastated and highly threatened ecosystem on the planet. The vast scope of habitat loss and extreme fragmentation in the AF hotspots has left intact very few extensive and continuous forested fragments. We compared bird assemblages between small (<100 ha) and large (>6,000 ha) forest remnants, in one of the largest AF remnants in Argentina. We performed 84 point-counts of birds in four large fragments (LF) and 67 points in 25 small fragments (SF). We recorded 4,527 bird individuals belonging to 173 species; 2,632 belonging to 153 species in LF and 1,897 in 124 species in SF. Small fragments suffered a significant loss of bird richness, mainly forest dependent species, but the birds abundance did not decrease, due to an increase in abundance of forest independent and semi-dependent bird species (edge and non forest species) that benefit from forest fragmentation. The bird guilds of frugivores, undestory, terrestrial and midstory insectivores, nectarivores and raptors, and the endemic species of AF were area sensitive, decreasing significantly in richness and abundance in the SF. Terrestrial granivores were the only guild positively affected by forest fragmentation, containing mainly edge species, which forage in open areas or borders including crops. Our first observations on fragmentation effects on bird assemblages in the southernmost Argentinean Atlantic Forests did not validate the hypothesis on pre-adaptation to human disturbances in the bird communities of AF. On the contrary, we observed that forest dependent, endemic and several sensitive bird guilds were strongly affected by fragmentation, putting in evidence the vulnerability to the fragmentation process and the necessity to conserve large remnants to avoid reduction of the high biodiversity of AF birds.     

Amphibian Chytrid Fungus Broadly Distributed in the Brazilian Atlantic Rain Forest

To investigate the occurrence of the chytrid fungus Batrachochytrium dendrobatidis in Brazil, we conducted histological screenings of 96 preserved specimens of anurans collected at 10 sites in the Atlantic rain forest. Data show this fungus to be widely distributed. Infected specimens included Colostethus olfersioides (Dendrobatidae), Bokermannohyla gouveai and Hypsiboas freicanecae (Hylidae), as well as Thoropa miliaris and Crossodactylus caramaschii (Leptodactylidae), extending the area of B. dendrobatidis occurrence in Brazil approximately 1,600 km N, 200 km S, and 270 km E. The altitudinal range of the chytrid is broad, spanning from less than 100 m (Estação Ecológica Juréia-Itatins, Reserva Biológica do Tinguá) to about 2,400 m (Parque Nacional do Itatiaia). An infection record dating to 1981 roughly coincides with the time of the first observations of amphibian declines in the country. Widespread occurrence of B. dendrobatidis in the Atlantic Forest adds to the challenge of conserving an already endangered biome given the potential risk of further local biodiversity loss. Further research is needed to understand how environmental and genetic factors relate to chytridiomycosis in leading to or preventing local die-offs. Protected sites at mid and high elevations may be particularly threatened, while lowland populations may be functioning as reservoirs. Conservation efforts should also involve monitoring studies and habitat protection.     

西双版纳热带季节雨林土壤氮含量对乔木树种多样性的影响?

大气氮沉降或人类活动导致生态系统氮输入增加,可能会提高土壤氮含量水平,促进优势种的生长和减少环境异质性,从而使物种共存的生态位减少,群落物种多样性降低。为研究土壤氮含量的增加对森林群落乔木树种多样性的影响,本研究在西双版纳热带季节雨林随机设置了14个1 ha的样方,对各样方土壤总氮( TN)含量、乔木树种丰富度以及西双版纳热带季节雨林20 ha动态监测样地中各样方乔木树种及建群种望天树( Parashorea chinensis)生物量进行了调查。结果表明：土壤氮含量与乔木树种丰富度具有显著负相关而与群落及建群种望天树生物量具有显著正相关。我们推测其机制可能是：土壤氮含量增加促进了建群种望天树等的生长及群落生物量的积累,减少树种共存的生态位,由于竞争排斥等原因而导致群落树种丰富度降低。因此,减少生态系统人为氮输入,对于保护西双版纳热带季节雨林乔木树种多样性具有重要意义。     

Abundance and Flower Visits of Bees in a Cerrado of Bahia,Tropical Brazil

Abundance, seasonal phenology and flower visits of eusocial bees were studied in Diamantina, a national park with cerrado vegetation in Bahia, tropical Brazil. About 700 bees were collected, mainly native stingless bees and the introduced Africanized honey bee. Sampling along a transect was most effective March through September during the dry season. The foraging worker bees were observed on flowers of over 60 angiosperm species of which a few were visited with high frequency. Foraging activity concentrated on flowering plants of the families Leguminosae and Asteraceae. The results are discussed under aspects of nutritional resource partitioning by bee communities in neotropical habitats and the specific composition of a cerrado apifauna.     

Genetic structure and conservation of Mountain Lions in the South-Brazilian Atlantic Rain Forest

The Brazilian Atlantic Rain Forest, one of the most endangered ecosystems worldwide, is also among the most important hotspots as regards biodiversity. Through intensive logging, the initial area has been reduced to around 12% of its original size. In this study we investigated the genetic variability and structure of the mountain lion, Puma concolor. Using 18 microsatellite loci we analyzed evidence of allele dropout, null alleles and stuttering, calculated the number of allele/locus, PIC, observed and expected heterozygosity, linkage disequilibrium, Hardy-Weinberg equilibrium, F(IS), effective population size and genetic structure (MICROCHECKER, CERVUS, GENEPOP, FSTAT, ARLEQUIN, ONESAMP, LDNe, PCAGEN, GENECLASS software), we also determine whether there was evidence of a bottleneck (HYBRIDLAB, BOTTLENECK software) that might influence the future viability of the population in south Brazil. 106 alleles were identified, with the number of alleles/locus ranging from 2 to 11. Mean observed heterozygosity, mean number of alleles and polymorphism information content were 0.609, 5.89, and 0.6255, respectively. This population presented evidence of a recent bottleneck and loss of genetic variation. Persistent regional poaching constitutes an increasing in the extinction risk.     

Massive Seed Predation of Pseudobombax grandiflorum (Bombacaceae) by Parakeets Brotogeris versicolurus (Psittacidae) in a Forest Fragment in Brazil1

Here we report massive seed predation of Pseudobombax grandiflorum (Bombacaceae) by Botogeris versicolurus (Psittacidae) in a forest fragment in Brazil. The intensity of seed predation was very high when compared to other studies in continuous forest, perhaps resulting from a scarcity of resources in such areas. This scarcity may limit the range of parrot's diet to a few plant species. It suggests that studies of Psittacidae seed predation may be important for conservation of some plants in fragments.     

Hunting Spiders of Woodland Fragments and Agricultural Habitats in the Atlantic Rain Forest Region of Brazil

The hunting spider communities of the Dionycha clade were studied 1986 through 1988 in fragmented woodlands and secondary agricultural habitats of the Botucatu area in São Paulo state, Brazil. The original vegetation of mainly tropical Atlantic rain forest (Mata Atlântica) was cleared already 70 years ago. In a total sample of over 1000 adult spiders, 247 species belonging to 12 families were determined. A decreasing frequency and diversity of spiders was found if forest remnants were compared with sugar cane fields and cattle pasture. The specific composition of the spider fauna as surveyed in different habitats is discussed under ecological aspects and in relation to the history of land use.     

The Use of Seeds by a Twig-Dwelling Ant on the Floor of a Tropical Rain Forest

The role of Pheidole praeses , a twig-nesting ant inhabiting the floor of the Brazilian Atlantic forest, as potential secondary seed disperser was investigated. A total of 901 seeds (20 morphospecies) were retrieved from 50 nests, most of them intact and able to germinate. Considering the abundance of Pheidole species and the evidence pointing to their potential as seed dispersers, these ants may be important determinants of the recruitment of small-seeded plants in tropical forests.
Abstract in Portugese is available at http://www.blackwell-synergy.com/loi/btp .     

Relation between environmental variables and aquatic megafauna in a first order stream of the Atlantic Forest, southern Brazil

The study was done in a first order stream in the southern portion of the Brazilian Atlantic Rain Forest. Samples of the aquatic megafauna (amphibians, crustaceans and fishes) were taken with the aim of describing spatial (longitudinal) and temporal (seasonal) patterns in species composition and abundance. Thirty four structural and limnological variables at macro and mesoscales from three sampling reaches were analysed. The spatio-temporal analysis of species richness and diversity indicated a gradient in which values increased in an upstream–downstream direction, independently of the season of the year. The results showed a strong influence of structural environmental variables on community structure. Furthermore, they revealed a hierarchical relation between macroscale and mesoscale variables and their influence on community abundance and composition in the various spatio-temporal sampling units analysed. The spatial distribution of species richness and diversity in the Carvão creek was strongly influenced by the presence of waterfalls, being progressively richer and more diverse downstream. Waterfalls seem to function as selective filters more than as absolute barriers, presenting different efficiencies for different species.     

A multimetric index based on benthic macroinvertebrates for evaluation of Atlantic Forest streams at Rio de Janeiro State, Brazil

This study describes the application of a protocol for biological assessment of water quality at first to third order streams at Serra dos órg?os, an area covered by Atlantic Forest in Rio de Janeiro State, Brazil. Major impacts in the region are domestic effluents and deforestation. Our main objective is to establish biocriteria for the establishment of the Serra dos órg?os Multimetric Index (SOMI) based on benthic macroinvertebrates. We used data from previous studies, sampled by experienced biologists, from 1999 through 2002. The benthic macroinvertebrate community was sampled in 12 reference sites and seven impaired sites in three river basins: Guapimirim, Macaé and Grande, all from the same bioregion. From the 22 tested metrics, 6 were included in the SOMI (% Diptera, % Coleoptera, Family Taxa, EPT Taxa, BMWP-CETEC and % Shredders). Scores (5, 3 or 1) were developed for these metrics to allow for aggregation into the index. Seven intermediately impaired sites were used for evaluating the applicability of the multimetric index. We concluded that the SOMI is a robust easy-to-apply tool for biomonitoring programs in the Serra dos órg?os region, south-east Brazil. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorised users. Handling editor: D. Dudgeon     

Ethnobotany of Atlantic Forest Coastal Communities: II. Diversity of Plant Uses at Sepetiba Bay (SE Brazil)

This is an ethnobotanical study of Atlantic Forest coastal communities located at Sepetiba Bay, Rio de Janeiro State, Brazil. Atlantic Forest remnants are top priority conservation areas, and include native communities that depend on fish and small-scale agriculture. We conducted fieldwork in the community of Calhaus (Jaguanum Island) from 1989 to 1991, and interviewed adults on their use of plants. We examined the diversity of medicinal plants used among communities of different islands and found results similar to previous research at Gamboa (Itacuruçá Island); communities living in smaller islands and on islands further from the coast use a lower diversity of plants. Also, older islanders show a deeper knowledge of medicinal plants than younger islanders.     

A new species of Inga (Fabaceae,Mimosoideae, Ingeae) from Atlantic Forest in Bahia,Brazil

Inga unica Barneby & J. W. Grimes, notable for a syndrome of: a) softly pilose foliage, b) emarginate leafstalks lacking nectaries, c) leaflets 2–3 pairs, of moderate size, d) filiform pliant peduncles, e) globose capitula, f) elongate linear floral bracts persistent after fall of the flowers, g) calyx more than half as long as corolla, and h) thin-textured fruit shattering after falling, is described, figured, and discussed. It appears related toI. (Leptinga) nutans (Vellozo) Martius ex Bentham.     

Three new species of melastomataceae from the southeastern Atlantic Forest of Brazil

Three species are described here that occur in montane and high-montane forests in Southeastern Brazil.Miconia shepherdii belongs to sectionGlossocentrum and occurs on the Serra da Mantiqueira, on the border between the states of São Paulo, Minas Gerais, and Rio de Janeiro.Miconia kollmannii belongs to sectionHypoxanthus (formerChaenanthera) and occurs in the state of Espírito Santo.Ossaea suprabasalis was also collected in the state of Espírito Santo.