Benthic macroinfaunal assemblages associated with Amazonian saltmarshes

The composition and abundance of the poorly known benthic macroinfauna associated with northern Brazilian saltmarshes, were described from eight sites (between 0°42′2.5″S, 47°52′44.1″W and 0°50′17.3″S, 46°36′13.3″W) along the Pará coast, Brazil. Sampling was carried out in November of 2007. Univariate and multivariate analyses were used to test for differences in sediment, vegetation and macroinfaunal variables among sites. No vertical zonation of the macroinfauna was detected. Macroinfaunal structure differed greatly among sites with different sediment and vegetation characteristics. Number of individuals and taxa were low in sites with sandy sediments and short, sparse vegetation and high in those with silty sediments with high organic matter and water contents, and tall, dense vegetation. Increasing number of individuals and taxa were associated with a geographical gradient in pore water salinity, which increases from west to east, coinciding with patterns of rainfall described for the Pará coast.     

A new genus of <Emphasis Type="Italic">Monimiaceae</Emphasis> from the Atlantic Coastal Forest in South-Eastern Brazil

Summary  A new monotypic genus and a new species of Monimiaceae, Grazielanthus arkeocarpus from the Brazilian Atlantic coastal forest are described, illustrated and compared with morphologically related taxa. The new taxon occurs in the State of Rio de Janeiro in the central coastal plain and was collected in the Po?o das Antas Biological Reserve, municipality of Silva Jardim (22°30′– 22°33′S; 42°14′– 42°19′W). The new taxon is represented by dioecious climbing shrubs of the sub-canopy that have urceolate, four-lobed flowers and a fleshy hypanthium that is closed until the fruit ripens. When ripe, the hypanthium ruptures irregularly and the fruitlets are exposed. The relationships between the new genus and other neotropical (Hennecartia J. Poiss. and Macrotorus Perkins) and paleotropical (Palmeria F. Muell.) genera are discussed.     

Altitudinal zonation of human-disturbed vegetation on Mt. Tianmu,eastern China

Much of the primary vegetation at low altitudes has been greatly altered or destroyed by a long history of human activities. This is particularly true in eastern China, where low-altitude areas are now dominated by secondary forests or plantations. Altitudinal vegetation zonation of this region is often based on these secondary forests, resulting in seral vegetation with an obscure zonal sequence. Here, we deduced the potential climax vegetation according to the regeneration patterns of the dominant species of the secondary forests at low altitudes (below 1,000 m a.s.l.) on Mt. Tianmu (1,506 m a.s.l., 30°18′30″–30°21′37″N, 119°24′11″–119°27′11″E). Based on the potential climax vegetation combined with the floristic composition and community structure, three vegetation zones were identified, viz: (1) evergreen broad-leaved forest zone (400–950 m a.s.l.); (2) evergreen and deciduous broad-leaved mixed forest zone (950–1,100 m a.s.l.); (3) deciduous broad-leaved forest zone (1,100–1,506 m a.s.l.). The altitudinal vegetation zones identified in this study correspond with the thermal conditions on Mt. Tianmu. The distribution of vegetation on Mt. Tianmu was limited by lower temperatures in winter, and the altitudinal thermal vegetation zones on this mountain were more similar to the thermal vegetation of Japan than to that of China. The vertical distributions and roles of conifers were different between the eastern and the western regions along 30°N latitude in humid East Asia. Cryptomeria fortunei formed the emergent layer, towering above the broad-leaved canopy at middle altitudes as C. japonica on Yakushima, but disappeared at high altitudes with hydrothermal limitation on Mt. Tianmu.     

Use and knowledge of plants by “<Emphasis Type="Italic">Quilombolas</Emphasis>” as subsidies for conservation efforts in an area of Atlantic Forest in Espírito Santo State,Brazil

The present work was undertaken in the Cachoeira do Retiro “Quilombola” community, located in the municipality of Santa Leopoldina (20°06′04″S × 40°31′47″W), in Espírito Santo State, Brazil. We expected to encounter high levels of ethnobotanical knowledge in the community due to its distance from the principal local urban center and its localization in a region of high biodiversity. Field work was undertaken between August 2005 and August 2006, employing semi-structured interviews, participant observation, artifact-interviews, as well as the “walk-in-the-forest” technique in the company of a local specialist. Ten additional informants participated in the research (seven women and three men with ages between 42 and 84) who were identified using the “snow-ball” method. A total of 192 ethnospecies belonging to 188 distinct plant taxa were cited (with 59% being native to the Atlantic Forest biome) and were classified into the following use-categories: medicinal (52%), food (34%), construction (18%), technology (10%), ritualistic (5%), ornamental (5%), and fuelwoods (2%). The plants with the greatest Use-Values were Attalea humilis (1.3) and Polyandrococos caudescens (1.1). The Diversity Index of the community’s ethnobotanical knowledge (5.12 nats) was found to be higher than seen in other ethnobotanical studies undertaken in the Atlantic Forest. Using a methodology for determining conservation priorities it was found that 17 of the 49 species analyzed should be examined more closely in studies that could help guarantee the continuity of their populations in the local forest fragment in light of their low density and intense utilization by the Retiro Quilombola community.     

The Conservation Value of Small Fragments For Atlantic Forest Reptiles

Loss and fragmentation of natural habitats are key contributors to the decline of populations and impoverishment of biological communities. The response to these disturbances can vary substantially among taxa and depends on spatial metrics of habitat fragments and the surrounding landscape. Herein we test how fragment area, shape, isolation, and matrix quality affect reptile richness, abundance, and occurrence in Brazilian Atlantic Forest fragments, a biodiversity hotspot with a poorly studied reptile fauna. We used 23 forest fragments, ranging from 2 to 30 hectares, surrounded by different matrix types, including sugarcane crop fields, cattle ranching, subsistence farmlands and rural communities. Species richness, total reptile abundance, population abundance, and occurrence probability of many species decreased with fragment area. Model selection suggested that fragment area is the main predictor of both richness and abundance, but matrix quality as well as fragment shape are also important predictors. For population abundance and occurrence probability, fragment area and proximity were the most important predictors followed by fragment shape and matrix quality, but the strength and even the sign of predictors varied substantially among species. We highlight that the value of small fragments should not be neglected for the conservation of Atlantic Forest reptiles.     

<Emphasis Type="Italic">Membraniporopsis tubigera</Emphasis>, an invasive bryozoan in sandy beaches of southern Brazil and Uruguay

The massive irruption of the invasive bryozoan Membraniporopsis tubigera (Osburn) in sandy beaches of southern Brazil and Uruguay is reported. The species, originally described from Puerto Rico, Texas and Florida, has also been recorded for Brazilian beaches from 21°S to 26°S as well as for harbours of Australia, New Zealand and the Sea of Japan. The southward spreading rate of this bryozoan along the Brazilian and Uruguayan coasts can be estimated in approximately 183–195 km year⁻¹. The chances that this invasion could proceed southwards in the Southwest Atlantic and the possible impacts that it may be causing are discussed. The case of M. tubigera seems to be qualitatively and quantitatively different from those of other alien bryozoans previously recorded for this region, since it appeared massively in exposed sandy beaches, a habitat regarded to date as apparently free from the pervasive ecological impact of invasion by exotic species in the Southwest Atlantic.     

Dynamics of a dry forest fragment after the exclusion of human disturbance in southeastern Brazil

Changes in the structure and composition of a dry forest fragment were described for a 4-yr period (1994–1998) in the southeastern Brazil (19°12′05″ S and 47°08′02″ W). This is the first dynamic study of a vanishing type of dry forest, which grows on base-rich soils originating from the basalt bedrock of western Minas Gerais State. A survey of trees ≥ 3.2 cm dbh (diameter at breast height, or 1.30 m) was conducted in 26 transects of 50 m × 6 m (0.78 ha). The species were classified into three regeneration guilds – pioneer, light-demanding and shade-tolerant – on the basis of others studies and personal observation. There was a decrease of 10.1% in the number of trees between 1994 and 1998. However, the basal area had an increase of 1.5% in the same period. Size class distributions in 1994 and 1998 were significantly different. The smallest trees (diameter < 10 cm) had the highest mortality rates. Although stand composition showed little change, a few species showed significant imbalance between recruitment and mortality. The studied fragment had mortality (2.3% yr^–1) and recruitment (1.6% yr^–1) rates similar to other tropical rain forests for trees ≥ 10 cm dbh. The present fragment of forest (turnover time = 39.5 yr, at cut level 10 cm dbh) lies among the most dynamic tropical forests. The main compositional changes were the increase of shade-tolerant trees and decline of pioneer species. The changes in composition and structure over the survey period may reflect the recovery of the forest after 4 yr of conservation. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effects of habitat transitions on rainforest bird communities across an anthropogenic landscape mosaic

We compared bird community responses to the habitat transitions of rainforest‐to‐pasture conversion, consequent habitat fragmentation, and post‐agricultural regeneration, across a landscape mosaic of about 600 km² in the eastern Australian subtropics. Birds were surveyed in seven habitats: continuous mature rainforest; two size classes of mature rainforest fragment (4–21 ha and 1–3 ha); regrowth forest patches dominated by a non‐native tree (2–20 ha, 30–50 years old); two types of isolated mature trees in pasture; and treeless pasture, with six sites per habitat. We compared the avifauna among habitats and among sites, at the levels of species, functional guilds, and community‐wide. Community‐wide species richness and abundance of birds in pasture sites were about one‐fifth and one‐third, respectively, of their values in mature rainforest (irrespective of patch size). Many measured attributes changed progressively across a gradient of increased habitat simplification. Rainforest specialists became less common and less diverse with decreased habitat patch size and vegetation maturity. However, even rainforest fragments of 1–3 ha supported about half of these species. Forest generalist species were largely insensitive to patch size and successional stage. Few species reached their greatest abundance in either small rainforest fragments or regrowth. All pastures were dominated by bird species whose typical native habitats were grassland, wetland, and open eucalypt forest, while pasture trees modestly enhanced local bird communities. Overall, even small scattered patches of mature and regrowth forest contributed substantial bird diversity to local landscapes. Therefore, maximizing the aggregate rainforest area is a useful regional conservation strategy.     

The persistence of the snow petrel (Pagodroma nivea) in Dronning Maud Land (Antarctica) for over 37,000?years

Two samples of snow petrel Pagodroma nivea mumiyo (solidified stomach oil) from Heimefrontfjella (74°34′36″S, 11°13′24″W) in Dronning Maud Land, Antarctica, were radiocarbon dated at 37,400 ± 1,500 and 3,120 ± 70 years old (dates are corrected for the ‘reservoir effect’). The age of the older sample provides further evidence that snow petrel colonies have existed in the mountain peaks of Dronning Maud Land since before the last glacial maximum (approx. 20,000–16,000 years ago). This finding also pushes back the estimated timing of establishment of snow petrel breeding colonies in this part of the continent by several thousand years. The variation in the accumulation rates of these two samples (1.6 and 35.2 mm per millennium, respectively) supports previous observations that mumiyo accumulation rates are highly variable and probably relate to site-specific factors affecting accumulation and degradation of the oil. Studies that help us understand historical bird population distributions in continental Antarctica can significantly aid the development and refinement of models that explain glacial advancement and retreat, the relationship between sea ice and population viability and, perhaps, predict species responses to future climate shifts.     

Bird communities in rainforest fragments: guild responses to habitat variables in Tabasco,Mexico

The effects of habitat loss and fragmentation in tropical forests are difficult to separate, as they usually occur concurrently. In the state park La Sierra, in Tabasco, Mexico, the rainforest is being cleared for pasture, and fragments are being used by local inhabitants. This study examined the response of bird feeding guilds to habitat characteristics, including human disturbance, in five fragments of different sizes (1 ∼ 4,500 ha, 2 ∼ 150 ha, and 2 ∼ 80 ha). Using point count observations, 125 species were recorded and were grouped into 11 feeding guilds. As expected, the largest fragment had higher species richness and abundances than the smaller fragments. However, five habitat features differed significantly among fragment sizes, including tree density, the number of tree stumps and the number of trails. Thus the larger fragment was also less disturbed. Fragment size alone was significant only for scavenger species richness, and for the abundance of bark gleaning insectivores and insectivore/nectarivores. Raptors were more diverse and abundant in the large fragment and less disturbed sites. Arboreal frugivores and bark or foliage gleaning insectivores, depended on higher trees and less disturbed sites. A better understanding of the mechanisms that affect persistence is essential for the planning of conservation actions.     

Phenology and dispersal modes of wood species in the Carrasco,a tropical deciduous shrubland in the Brazilian semiarid

We provide, for the first time, data on phenology and dispersal modes for the Carrasco, a tropical deciduous shrubland in the Brazilian semiarid. The study was conducted in the Serra das Almas Reserve (5°8′45″S, 40°55′43″W), northeastern Brazil. We sampled 2,790 individuals from 39 species, 30 genera, and 17 families. Fabaceae, Euphorbiaceae, and Myrtaceae were the most representative. All species lose leaves, fully or partially, during the dry season. Leaf flush was observed to increase at the end of the dry season with a peak during the rainy season. Similarly, the peak of flowering/fruiting occurred at the end of the dry and the beginning of the rainy season. Air humidity and maximum temperature were the only variables correlated with leaf flush. Most species showed annual flowering/fruiting. Flowering lasted 2–5 months, but even longer fruiting periods were observed. Zoochory was the most frequent dispersal mode, followed by autochory. Zoochoric, barochoric, and autochoric species fruited throughout the year, while for anemochorics fruiting occurred at the end of the rainy and/or during dry season. Despite both, the Carrasco and the Caatinga are deciduous, the Carrasco has a greater intensity and duration of phenological events and a higher frequency of zoochory, thus being more similar to less arid ecosystems. We discuss the local implications of these patterns, as well as how our results are in accordance with other regional and global studies with similar approaches.     

An initial comparison of tubular netting versus tie–tie methods of cultivation for Kappaphycus alvarezii (Rhodophyta, Solieriaceae) on the south coast of Rio de Janeiro State, Brazil

A new cultivation technique for Kappaphycus alvarezii was used in the Brazilian southeastern coast (23°02′25″ S and 43°53′39″ W), the tubular netting on floating rafts. The tubular net technique (TN) was compared with the current method of tie–tie (TT). After 47 days, the daily growth rate (mean ± SD of TN and TT = 3.4 ± 0.7% day⁻¹), carrageenan yield (mean ± SD of TN and TT = 36 ± 1.3%), gel strength (mean ± SD of TN and TT = 730 ± 114.5 g cm2), and viscosity (mean ± SD of TN and TT = 350 ± 60.4 cP) did not differ between the two techniques (p > 0.05). The amount of time used to plant (TT = 30.2 ± 2.3 min and TN = 13.3 ± 3.4 min) and to harvest the seedlings (TT = 36.2 ± 2.7 min and TN = 17.8 ± 3.7 min) were lower in TN (p < 0.001). It is concluded that TN was more effective than TT, the cultivation management (time rates used to plant and harvest the seedlings) was 53.6% faster, no seedlings were lost, the cost was lower, and an estimated return in 1 year of nearly 20% more than that of the TT technique.     

Forms of rarity of tree species in the southern Brazilian Atlantic rainforest

The assessment of species rarity considers local abundance (scarce or abundant population), habitat affinity (stenoecious or euryecious species), and geographic distribution (stenotopic or eurytopic species). When analyzed together these variables classify species into eight categories, from common species to those having small populations, unique habitats, and restricted geographic distribution (form 7), as proposed by Rabinowitz in 1981. Based on these categories, it is possible to calculate the frequency of the different forms of rarity of the species present in a given site. The Brazilian Atlantic rainforest is considered a hotspot of the world biodiversity harboring many endemic species, which have restricted geographic distribution. Our objective was to identify the forms of rarity of tree species and their proportions in the southern portion of the Brazilian Atlantic rainforest using Rabinowitz’s forms of rarity. All the seven forms of rarity are present in the 846 tree species we analyzed: 46% eurytopic and 54% stenotopic, 73% euryecious and 27% stenoecious, 76% locally abundant and 24% locally scarce species. Eurytopic, euryecious locally abundant species accounted for 41.1%, whereas 58.9% were somehow rare: 4.5% eurytopic, euryecious locally scarce, 0.2% eurytopic, stenoecious locally abundant, 0.1% eurytopic, stenoecious locally scarce, 19.5% stenotopic, euryecious locally abundant, 8.0% stenotopic, euryecious locally scarce, 15.6% stenotopic, stenoecious locally abundant, and 11.0% stenotopic, stenoecious locally scarce. Considering that the most restrictive forms of rarity precedes extinction, the application of Rabinowitz’s system demonstrated that most tree species of the southern Brazilian Atlantic rainforest are threatened due to their restricted geographic distribution, restriction to a single habitat, reduced local abundance, or even to a combination of these variables.     

Parallel declines in species and genetic diversity in tropical forest fragments

The potential for parallel impacts of habitat change on multiple biodiversity levels has important conservation implications. We report on the first empirical test of the 'species-genetic diversity correlation' across co-distributed taxa with contrasting ecological traits in the context of habitat fragmentation. In a rainforest landscape undergoing conversion to oil palm, we show that depauperate species richness in fragments is mirrored by concomitant declines in population genetic diversity in the taxon predicted to be most susceptible to fragmentation. This association, not seen in the other species, relates to fragment area rather than isolation. While highlighting the over-simplification of extrapolating across taxa, we show that fragmentation presents a double jeopardy for some species. For these, conserving genetic diversity at levels of pristine forest could require sites 15-fold larger than those needed to safeguard species numbers. Importantly, however, each fragment contributes to regional species richness, with larger ones tending to contain more species.     

Effect of fragmentation on the community structure of epixylic bryophytes in Atlantic Forest remnants in the Northeast of Brazil

The effects of fragmentation and edge effects on the floristic composition, richness, diversity and abundance of epixylic bryophytes (growing on decaying wood) were investigated in ten fragments of Atlantic Forest remnants in the Northeast of Brazil. In each fragment, four perpendicular 100 m transects were demarcated. Along these transects, samples of bryophytes growing on decaying wood were collected. The forest fragments were grouped in three size classes (small: <100 ha; medium: 100–500 ha; large: >500 ha). Correlation and multivariate analysis were undertaken between bryophyte flora and fragment metrics (size, form, isolation, altitude variation, nuclear area and secondary vegetation percentage and distance from the edge). A total of 99 species of bryophytes, 52 liverworts and 47 mosses were registered. The statistical results confirming fragment size is an important factor in epixylic community structure. Therefore, composition, richness, diversity and abundance can be better explained by a junction of all studied landscape factors. Bryophyte richness, the percentage of samples with the greatest coverage of decaying wood and shade-tolerant species’ distribution, were not correlated to distance from the forest edge. This suggests that edge effects are not linear or can be detected beyond 100 m from the edge, which is very important for inclusion in future studies.     

How well do single samples reflect rotifer species diversity? A test based on interannual variation of rotifer communities in Big Bend National Park (Texas,USA)

Studies of rotifer community composition and dynamics often rely on limited sampling regimes. To determine how well species richness is reflected in these studies, we examined interannual variation of rotifer species richness and monogonont community structure from 10 aquatic systems comprising four habitat types—springs, rock pools (tinajas), former cattle tanks, and artificial ponds—in Big Bend National Park (Texas, USA). Planktonic, littoral, and benthic samples were collected from all sites at about the same date for each of five summers (2001–2005). Our survey yielded 15 monogonont families including 30 genera and 84 species. Two bdelloid taxa also were designated. Species richness varied widely among these four habitats: range, 1–32; mean (±1 SD), 11.2 ± 8.0. Total Species richness in the habitats also varied considerably: springs (54 taxa) > artificial ponds (35 taxa) > tinajas (19 taxa) > cattle tanks (15 taxa). Sessile species comprised ≈13% of the taxa in our samples. Species turnover indices (STI) of these systems indicate low overall relatedness: mean (±1 S.D.) = 85.2 ± 7.1%. The relative frequency of encounter of most taxa in the four systems was low, with 79 taxa (≈92%) having values ≤2.0%. Singleton rates were quite high, ranging from 46.7 to 71.4%, with an overall mean ≈65.1%. Most importantly, we found that both species richness and STI varied considerably among habitat type. Species richness varied by 2–10× between consecutive years and STI ranged from 64 to 89% over the entire study. Our results indicate that rotifer community composition fluctuates greatly over time, and that rotifer community structure may be more labile than is generally believed. Species richness and thus biodiversity may be dramatically underestimated using single sampling or short-term strategies that are often employed in studies of zooplankton community structure. Guest editors: S. S. S. Sarma, R. D. Gulati, R. L. Wallace, S. Nandini, H. J. Dumont & R. Rico-Martínez Advances in Rotifer Research     

Allometry of aboveground biomasses in mangrove species in Itamaracá, Pernambuco, Brazil

Allometric equations to estimate aboveground biomass (AGB) and plant part biomasses (PPB) of three mangrove species, Rhizophora mangle, Avicennia schaueriana, and Laguncularia racemosa, were determined in Itamaracá, Pernambuco, Brazil (7°48′44″S and 34°49′39″W). Twenty-three to thirty-six trees of each species, ranging in height (H) from 1.6 to 11.8 m and in diameter, at breast height or above prop roots (D), from 2 to 21 cm, were measured, cut, and separated into stems, branches, leaves, and prop roots. Biomass proportions in each tree part were similar among species, excluding prop roots: stems 37–47%, branches 41–46%, and leaves 11–17%. Prop roots represented 37% of AGB in R. mangle. Tree size had a significant but not large influence on biomass distribution among plant parts: as stem diameters increased the proportions allocated to leaves decreased and those to stems and branches increased. AGB and PPB were significantly related to D and D² × H and the best fittings were obtained with power equations. A few equations from literature fitted the data reasonably well for AGB of one or two of the species but resulted in large errors for the others. Applying the equations to previous measurements of tree diameters in a sample area, AGB for the mangrove site was estimated at 105 Mg ha⁻¹, with 78, 19, and 3% corresponding to biomasses of R. mangle, L. racemosa, and A. schaeuriana trees, respectively.     

Distribution patterns of flora and fauna in southern Chilean Coastal rain forests: Integrating Natural History and GIS

Knowledge of species richness centers is necessary for the design of conservation areas. In this study, we present a GIS analysis of two years of field data on animal and plant diversity distributions in evergreen, coastal rain forests of southern Chile (39°30′–41°25′ S). Despite their high endemism, these forests have remained largely unprotected. Field records were complemented with data from museum collections and scientific literature. We used selected environmental variables (evapotranspiration, altitude) and, in some cases, forest types as predictors of species distributions. Our study focused on the distribution of forest bryophytes, vascular plants, soil invertebrates, amphibians and birds. We generated distributional maps for each taxa based on their field records in the study area, complemented by natural history information, except in the case of bryophytes and soil invertebrates. In general, species richness was lower at 600 m elevation or above for all the taxa studied. Species richness tends to increase in the northern sector of the study area. We observed a greater richness of vascular plants near rivers and streams, and noted important floristic differences between west and east-facing slopes of the Coastal Range, with more species in the oriental side. Because species in high altitude forests are not a subset of those found at lower elevations, we propose that conservation strategies should prioritize the protection of the entire altitudinal gradient of the southern Coastal Range, especially in the more diverse oriental and northern sectors.     

Isolation of a strong promoter fragment from endophytic Enterobacter cloacae and verification of its promoter activity when its host strain colonizes banana plants

To engineer endophytic Enterobacter cloacae as a biocontrol agent against banana fusarium wilt, a promoter-probe plasmid pUCK was constructed to identify a strong promoter to express disease resistance genes. Using a kanamycin resistance gene for selection, 10 fragments with strong promoter activity were identified from the genome of the E. cloacae KKWB-10 strain. The regions of these 10 fragments that were the primary contributors to the promoter function were identified, and their promoter activities were further evaluated using green fluorescent protein (GFP) as a reporter gene. Fragment 132a″ drove the highest level of GFP activity when the bacteria bearing the fragments were cultured in Luria–Bertani and banana stem extract media. The GFP-expressing strain harboring fragment 132a″ (K-pUCK7-132a″-GT) was then inoculated into banana plantlets (about 1 × 10⁷ CFU per plant) to verify the activity of fragment 132a″ in planta. Ten days after inoculation, tissue sections of these banana plantlets were observed by laser confocal scanning microscope. Green fluorescence was observed in the tissues of banana plantlets inoculated with K-pUCK7-132a″-GT but not in uninoculated controls. These results suggest that fragment 132a″ possesses strong promoter activity when its host strain colonizes the banana plants and can be used to engineer endophytic E. cloacae KKWB-10 for biocontrol.