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1.
Aiming to evaluate the potential of Passerine birds as bioindicators of forest fragmentation, we studied the avifauna in the mountain region of the state of Rio de Janeiro by mist-netting between 2001 and 2005. We sampled six sites, including four small fragments (from 4 to 64 ha) in an agricultural area (Teresópolis), one second-growth forest (440 ha - Miguel Pereira) and a continuous forest (10,600 ha, Serra dos Org?os National Park - SONP). Indicator Species analysis and a Monte Carlo test were run to detect associations between species and sites, considering at least 30% of perfect indication and a significant value for the statistical test, only considering species with at least 10 captures. A total of 30 Passerine birds were sampled, and due to their association to the largest area (SONP), we considered Sclerurus scansor, Mionectes rufiventris, Chiroxiphia caudata and Habia rubica as the best indicators for this area. Five species were more captured not by chance in the 440 ha second-growth: Conopophaga melanops, Myiobius barbatus, Myrmeciza loricata, Philydor atricapillus and Schiffornis virescens and no species were related to any small fragment. This analysis has identified specialized Passerine species in many aspects (foraging substract, needs for nesting, rarity status), and it can be a valuable tool for detecting possible bioindicators.  相似文献   

2.
The phlebotomine fauna is highly varied in Três Bra?os, an endemic area of american cutaneous leishmaniasis, situated in the cacao growing region in the southeast of Bahia State, Brazil. Thirty spécies of the Lutzomyia genus were identified in 13,535 specimens collected between 1976 and 1984. Lutzomyia whitmani was the dominant species accounting for 99% of flies in the peridomicile and 97.5% of those caught in homes. In the forest the predominant species were Lu. ayrozai and Lu. yuilli. Lu. whitmani accounted for only 1.0% of the specimens examined. Lu. flaviscutellata, the proven vector of Leishmania mexicana amazonensis, was also collected in small numbers. Lu. wellcomei, a known vector of L. braziliensis braziliensis in the Serra dos Carajás, Pará, Brazil was not encountered in the Três Bra?os region where the parasite causing human infections is usually L.b. braziliensis. Although we have not encountered a natural infection with leishmanial promastigotes in 1,832 females of the various species examined, we discuss the probability that Lu. whitmani is the vector of L.b. braziliensis in the region maintaining transmission in dogs and man.  相似文献   

3.
We developed a multimetric index based on macroinvertebrates to assess ecological condition of wadeable streams in Rio de Janeiro State, southeast Brazil. To do so we used a set of 12 reference and 12 severely impaired sites sampled in the summer wet season as calibration sites. Nine metrics were selected based on their abilities to distinguish between reference and impaired sites and their independence from other metrics. Metrics retained in the final index were: family richness; Trichoptera family richness; Shannon family diversity; % Plecoptera individuals; % Ephemeroptera, Plecoptera and Trichoptera (EPT) individuals; % mollusk and Diptera individuals; % shredder individuals; proportion Chironomidae/Diptera individuals; and proportion Hydropsychidae/Trichoptera individuals. The final 9 metrics were standardized; then the Guapiaçu-Macau Multimetric Index (GMMI) was calculated, yielding a final index score ranging from 0 to 100. We validated the index through use of 19 sites subject to different levels of impairment, sampled both in summer and in winter. Our final multimetric index distinguished well between different levels of impairment and was strongly correlated with other disturbance measures. Temporal stability was also tested through use of 8 sites that were sampled in both seasons, and results showed no significant changes in the index final score among seasons. Our research represents one of the first initiatives in Brazil to develop a multimetric index for use in a spatially extensive bioassessment program extending across substantial natural and disturbance gradients. It can be a useful tool to help conserve streams in Atlantic forest conservation areas. We suggest that the methodology established here offers a foundation for similar index development and assessments in Brazil.  相似文献   

4.
Alcantarea martinellii is described and illustrated as a new species endemic to Serra dos Órgãos, Petrópolis, Rio de Janeiro State, Brazil. The presence of a simple and erect inflorescence concomitant with a conspicuous water impounding rosette is an unreported combination of characters for Alcantarea. This new lithophytic taxon is unique, with no obvious close relative, but it is similar to A. benzingii, A. farneyi, and A. hatschbachii, which also have unbranched inflorescences.  相似文献   

5.
Three new species of Peristicta Hagen in Selys from Brazil are described and illustrated: P. janiceae from Minas Gerais State (Diamantina, Gouvêa, Lagoa Santa, Serra do Cara?a, Serra do Cipó, Urobotanga), P. jalmosi from Goiás State (Chapada dos Veadeiros, Reserva da Universidade de Brasília) and Minas Gerais State (Urobotanga, Lagoa Santa, Ponte Nova, S?o Jo?o del Rey,) and P. muzoni from Mato Grosso State (Serra da Bodoquena). An identification key for males of Peristicta is presented.  相似文献   

6.
We developed a preliminary fish-based multimetric index (MMI) to assess biotic condition of Atlantic Rain Forest streams in Southeastern Brazil. We used least-disturbed sites as proxies of reference conditions for metric development. To determine the disturbance gradient we used an Integrated Disturbance Index (IDI) that summarized the multiple disturbances measured at local/regional catchment scales in a single index, describing the totality of exposure of the streams to human pressures. For our 48 sites, nine were least-disturbed (IDI < 0.25), five were most-disturbed (IDI > 1.35) and 34 were intermediate. Initially, we considered 41 candidate metrics selected primarily from previous studies. We screened this pool of candidate metrics using a series of tests: range test, signal-to-noise test, correlation with natural gradients, responsiveness test, and redundancy test. After screening, we selected six metrics for the MMI: % Characiform individuals, % water column native individuals, % benthic invertivorous individuals, % tolerant species, % intolerant species, and % detritivorous individuals. Metrics such as diversity, dominance, species richness and biomass that have been historically used for assessing ecosystem condition failed one or more screening tests. We conclude that an IDI and rigorous metric screening are critical to the MMI development process and for meaningful assessments of stream condition.  相似文献   

7.
The chemical investigation of the aerial parts of Guatteria ferruginea collected in the National Park of Serra dos Órgãos, Teresópolis, Brazil and of Guatteria latifolia and Guatteria sellowiana collected in the National Park of Itatiaia, Itatiaia, Brazil resulted in the isolation and identification of six isoquinoline alkaloids, two aporphine alkaloids 3-hydroxy-nornuciferine (1), nornuciferine (2) and four oxoaporphine alkaloids lysicamine (3), isomoschatoline (4), liriodenine (5) and O-methylmoschatoline (6). The isoquinoline alkaloids were found in the species G. ferruginea, G. latifolia and G. sellowiana for the first time and they support the taxonomic position within the genus Guatteria. Isoquinoline alkaloids (5–6) can be considered chemotaxonomic markers of the subfamily Annonoideae.  相似文献   

8.
The common opossum of the Atlantic forest,Didelphis aurita Wied-Neuwied, 1826 is predominantly terrestrial, but uses the vertical space of the forest regularly. It is the didelphid that most frequently uses large supports in vertical movements. Here we test the influence of age and seasonality in fruit production on the vertical movements ofD. aurita. Animals were trapped in Serra dos órgăos, state of Rio de Janeiro, and equipped with a spool-and-line device before release. The paths were tracked, and variables related to support incline, diameter, distances and heights moved above ground were measured and compared between age classes and seasons. There were no significant differences between seasons. Individuals of all ages used the vertical space of the forest but the young opossums did it more intensively along their paths.  相似文献   

9.
Most bioassessment programs in Brazil face difficulties when scaling up from small spatial scales because larger scales usually encompass great environmental variability. Covariance of anthropogenic pressures with natural environmental gradients can be a confounding factor in the evaluation of biologic responses to anthropogenic pressures. The objective of this study was to develop a multimetric index (MMI) with macroinvertebrates for two stream types and two ecoregions in the Atlantic Forest biome in Rio de Janeiro state, Brazil. We hypothesized that by using two approaches – (1) testing and adjusting metrics to landscape parameters, and (2) selecting metrics using a cluster analysis to avoid metrics redundancy – the final MMI would perform better than the traditional approach (unadjusted metrics, one metric representing each category). Four MMIs were thus developed: MMI-1 – adjusted MMI with metrics selected after cluster analysis); MMI-2 – adjusted MMI with one metric from each category; MMI-3 – unadjusted MMI with metrics selected after cluster analysis; MMI-4 – unadjusted MMI with one metric from each category. We used three decision criteria to assess MMI’s performance: precision, responsiveness and sensitivity. In addition, we tested the MMI’s by using an independent set of sites to validate the results. Although all MMIs performed well in the three criteria, adjusting metrics to natural variation increased MMI response and sensitivity to impairment. In addition, the selected MMI-2 was able to classify sites of two stream types and two ecoregions. The use of cluster analysis, however, did not avoid high redundancy between metrics of different branches. The MMI-4 had the poorest performance among all tested MMIs and it was not able to distinguish adequately reference and impaired sites from both ecoregions. We present some considerations on the use of metrics and on the development of MMI’s in Brazil and elsewhere.  相似文献   

10.
Five new taxa in Eriocaulaceae from the Chapada Diamantina of Bahia, Brazil are described and illustrated and their diagnostic characters discussed and compared with other similar taxa. Eriocaulon ligulatum var. dimerum occurs only between Len?óis and Palmeiras; Paepalanthus carvalhoi occurs in Palmeiras, Mucugê and Barra da Estiva; P. umbrosus, P. multicapitatus and P. oblongifolius are known only from the Serra da Chapadinha near Len?óis.  相似文献   

11.
Ma T W  Huang Q H  Wang H  Wang Z J  Wang C X  Huang S B 《农业工程》2008,28(3):1192-1200
To develop benthic macroinvertebrate-based multimetrics for the bioassessment of the water quality of Taihu Lake, benthic macroinvertebrate assemblages were sampled at 60 sites in 8 subareas of Taihu Lake. A total of 24 species of benthic macroinvertebrates were obtained: 14 species of Mollusca, 5 species of Arthropoda and 5 species of Annelida. A comprehensive evaluation of the metrics was carried out. The results showed that 7 metrics (i.e., total number of taxa, the number of Mollusca & Crustacea taxa, % Mollusca & Crustacea, % Gastropoda, Goodnight-Whitley index, Hilsenhoff biotic index and % Collector-gatherers) were sensitive. A score of 5, 3 or 1 was assigned to every metric for standardization of the metrics, and a multimetric on a scale ranging from 7 to 35 for bioassessment was developed. Four-level discriminatory biocriteria for water quality were eventually proposed by quartation: 7–14, very poor; 15–21, poor; 22–28, fair; 29–35, good. The re-scored results from the 60 sites showed that the water quality of southeastern Taihu Lake was relatively good, whereas that of northwestern Taihu Lake was relatively poor. Basically, the discriminatory biocriteria are suitable for the assessment of the water quality of Taihu Lake.  相似文献   

12.
典型平原河网地区底栖动物生物指数筛选及评价基准研究   总被引:1,自引:0,他引:1  
2011年夏、秋季在上海市全境主要河流的83个断面进行大型底栖动物的采样, 共获取底栖动物20个分类单位(种), 其中软体动物、环节动物和节肢动物分别占50%、30% 和20%。选取常见的28个生物指数分别进行计算, 并采用非参数统计检验方法筛选出8个敏感生物指数。通过记分法对8种敏感生物指数统一量纲后, 获得数值范围为8-40的综合生物指数, 运用四分法划分了判别河道水环境质量的生物基准: 32-40, 较好(Good); 24-31, 一般(Fair); 16-23, 污染(Poor); 8-15, 严重污染(Very poor)。9个断面未发现活体生物, 定为超严重污染(Super poor)。依照生物基准比较上海市41个代表性断面近5年主要水质理化指标, 基本反映出水质理化指标的空间差异性, 该综合生物指数及判别基准也可适用于评价平原河网地区的河道水质状况。    相似文献   

13.
《L'Anthropologie》2023,127(2):103132
As part of the research program “Archaeology of rock art in Mato Grosso: the Chapada dos Guimarães National Park (Cuiabá, Brazil)” placed under the coordination of Patrick Paillet and Veronica Wesolowski, an integrated and interdisciplinary approach to the territory still largely unpublished rock art of the Chapada dos Guimarães, has been undertaken since 2020 by combining strictly archaeological research (surveys, excavations and prospecting-inventories), rock art studies (analysis and graphic, photographic and photogrammetric recording of representations) and geological analyzes and, to define and characterize the structure of its ornamented landscapes. Our program is an extension of other projects carried out from 1983 to 2013 under the direction of Agueda Vilhena-Vialou, Denis Vialou and Levy Figuti in the region of the Cidade de Pedra near Rondonópolis and at Santa Elina in the Serra das Araras (Jangada). The region of the Chapada dos Guimarães National Park (PNCG) was the subject of exploration and partial studies between 2017 and 2019 under the direction of Caroline Bachelet within the framework of the program “Prehistory and Paleoenvironments in the Pantanal region (Mato Grosso, Brazil)”. The pursuit of archaeological research in the PNCG contributes to better defining the chronology and the dynamics of occupations at local and regional scales, to characterizing chrono-culturally the settlements and their variability in the region, extending from the Rio Vermelho in the south to the Rio Cuiabá in the north, and to understand the processes of settlement and/or mobility of past populations along the firm lands and especially the hydrographic systems that border the floodplains of the Pantanal and which constitute the main routes of population movement.  相似文献   

14.
对太湖8个区域共60样点进行底栖大型无脊椎动物采样,共获得底栖动物24种,其中软体动物14种,节肢动物5种,甲壳动物5种.根据Hilsenhoff 生物指数确定了15个相对清洁的样点和45个污染样点,然后进行21种生物指数的综合评估,结果表明,总分类单元数、(甲壳动物 软体动物)分类单元数、%(甲壳动物 软体动物)、%腹足纲、Goodnight-Whitley指数、Hilsenhoff 生物指数和%直接收集者等7个底栖动物生物指数可以用作判别太湖水质的敏感生物指数.通过5, 3, 1记分法对6种生物指数统一量纲后,获得变化范围为7~35的综合生物指数,运用四分法划分了太湖水质判别的生物基准:7~14很差,15~21差,22~28一般,29~35好,并对60个样点进行重新记分,获得了太湖水质的基本生态分区现状,太湖的东南区属水质较好的区域,而西北区属水质较差的区域.该水质生物基准基本适合评价太湖不同区域的水质状况.  相似文献   

15.
Yeasts were isolated from three vineyards located in the South Region of Brazil. A cross evaluation was carried out at the oldest vineyard of the study in Pinheiro Preto. Samples of grape berries, grapevine leaves and the soil, along with samples of the winery equipment and effluent, were collected. In the Serra do Marari and Campos Novos vineyards only samples of grape clusters were obtained. The 106 yeast isolates were identified by sequencing the D1/D2 domain of LSU rDNA or ITS1-5.8S-ITS2 region in 22 species. The values for the richness indices varied between the vineyards. A comparison of the taxonomic diversity of the yeasts from these regions using the reciprocal Simpson index showed a significant difference between the Serra do Marari and Campos Novos vineyards (5.72?±?0.36 and 2.92?±?0.36, respectively, p?<?0.0001). The functional diversity was assessed in relation to the use of carbon and nitrogen sources by the yeasts isolated from each location. In general, we observed that the Pinheiro Preto and Campos Novos vineyards differed consistently from the Serra do Marari vineyard according to these indices (FAD2, FDc and Rao, p?<?0.0001). The possible spreading of Saccharomyces cerevisiae from the winery to the vineyard in Pinheiro Preto was observed.  相似文献   

16.
基于底栖生物完整性指数的赣江流域河流健康评价   总被引:4,自引:0,他引:4  
底栖生物完整性指数(B-IBI)是最为广泛应用的水生态系统健康评价指数之一。根据2009-2010年期间赣江流域60个采样点的底栖动物数据(15个参照点, 45个受损点), 对17个生物参数进行分布范围、判别能力和Pearson相关性分析, 确定了B-IBI指数体系由总分类单元数、甲壳和软体动物分类单元数、甲壳和软体动物%和BI指数构成。采用比值法统一各生物参数量纲, 将各个生物参数分值加和得到B-IBI指数值。根据参照点的B-IBI值的25%分位数值最终确定赣江流域河流健康评价标准。评价结果表明, 赣江流域60个采样点中19个为健康, 19个为亚健康, 14个为一般, 8个较差。综合来看, 赣江流域河流处于健康-亚健康状态: 上游各支流中绵水、贡江、上犹江和桃江为健康状态, 章水、濂水、梅江和平江为较差状态; 中游各支流健康评价结果多为健康-亚健康状态, 而乌江为较差状态; 下游各支流为健康-亚健康状态; 赣江干流上健康评价的结果均为健康。    相似文献   

17.
Assessing the ecological impacts of anthropogenic pressures is a key task in environmental management. Multimetric indices (MMIs), based on aquatic assemblage responses to anthropogenic pressures, have been used increasingly throughout the world. The MMI approach is a low-cost, rapid field method that produces an aquatic condition index that responds precisely to anthropogenic pressures, making it useful for conservation and environmental management. We developed four candidate MMIs based on benthic macroinvertebrate assemblages sampled at 40 randomly selected sites to assess the environmental condition of streams upstream of a hydroelectric power plant in the Brazilian Neotropical Savanna biome. Those MMIs were built from landscape-adjusted and unadjusted biological metrics as well as two alternative ways of choosing metrics. The alternative MMIs performances were tested by comparing their precision to distinguish least-disturbed areas, responsiveness to discriminate least- and most-disturbed areas, and sensitivity to anthropogenic pressures at catchment and local scales. The best performing MMI had landscape-adjusted metrics and was produced through use of principal component analysis for metric selection. It included 4 metrics: Ephemeroptera richness, average tolerance score per taxon, percentage of predator individuals, and percentage of Odonata individuals adjusted by elevation. This index discriminated well the anthropogenic pressures at local- and catchment-scales, and at both scales simultaneously, as indicated by an integrated disturbance index. Our methodological development included statistical criteria for identifying least- and most-disturbed sites, calibrating for natural landscape variability, and use of non-redundant metrics. Therefore, we expect it will provide a model for environmental assessment of water resources elsewhere in Brazil and in other nations.  相似文献   

18.
《Ecological Indicators》2008,8(5):582-587
An accurate assessment of estuarine condition is critical to determining whether there has been a change from baseline or ‘natural’ conditions; benthic communities are routinely used as an ecological endpoint to make this assessment. We addressed two issues, which arise when attempting to detect differences between benthic communities. The first is the varying sensitivity of metrics, e.g. one metric may not be able to detect differences between two communities where another metric can. The second is the influence of season on the detection of differences between benthic communities from different estuarine systems. In this study, benthic communities taken from depositional sites were sampled in three seasons, at three sites within two relatively pristine estuaries located in southern Massachusetts, USA. Statistical comparisons of benthic community data from the two estuaries were made using three common metrics: species richness, Shannon diversity and Bray–Curtis similarity indices. Significant community differences were found depending upon the index. The Bray–Curtis index, using permutation testing, was the only metric that detected differences between estuaries despite disparate seasonal sampling. This suggests that researchers do not need to be overly constrained to sampling in the same season when testing for differences in benthic communities between estuaries. Additionally, we propose an analytical method to identify anthropogenically impacted estuarine systems.  相似文献   

19.
Specific impacts and benefits of nature tourism on species, ecosystem and socio-economic aspects have to be addressed in detail. This study compared diurnal medium-large vertebrate richness and abundance in a visited (VT) and a non-visited trail (NVT) in the mountain forest of Serra dos Órgãos National Park (SONP), a priority area for nature conservation in the Atlantic Forest hotspot. Results suggest that richness and abundance of medium-large mammals and birds are significantly reduced in VT, however sample effort was insufficient for further analysis. In the absence of adequate data, protected area managers have to guarantee infrastructure and control, but first, limit access by visitors, to small sized groups and low in frequency, guaranteeing large refuges for wildlife, and effective contributions for nature conservation with real socio-economic benefits at local and regional scales. The Brazilian government is investing in tourism in National Parks, including SONP, but there are no directives to monitor and manage potential negative impacts. Researchers and managers need to work together to couple this economic activity with environmental conservation in SONP and other protected areas in Brazil.  相似文献   

20.
The aim of this study is to develop a benthic index of biotic integrity (B‐IBI) to help understand how the increasing anthropogenic pressure may impact the subtropical Xiangxi River in China. Benthic macroinvertebrate and environmental surveys were conducted at 77 sites in early summer 2004. Each collection site was categorized as reference or impaired based on physical, chemical, biological, and land‐use information. Six non‐redundant metrics from 35 metrics were used to differentiate between reference and impaired sites. We selected six metrics for the final IBI. The scoring criteria of each metric were normalized based on the quadrisection and 0–10 scaling systems. Both scaling methods were used to assess the aquatic health of each site in the Xiangxi River watershed. The results showed that most sites were in fairly poor condition. Furthermore, we identified the relationship between B‐IBI metrics, water‐quality, and land‐use variables with a principal component analysis. A composite of nutrients and land‐use intensity explained most variances. These results suggest that the B‐IBI may be a suitable method for assessing river conditions within the subtropical Xiangxi River in central China (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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