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1.
Ecol Appl ; 34(3): e2950, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38404050

ABSTRACT

Forest cover has been a pivotal indicator of biological conservation and carrying capacity for wildlife in forest ecoregions. Such a relationship underpins policies focused on the extension of protected lands. Here, we estimate aboveground biomass (AGB) as a proxy for habitat quality in seminatural rural patches and provide a comparison with approaches that only consider forest cover. We hypothesize that recommendations for biological conservation in agricultural landscapes are substantially improved if habitat quality is also taken into account, and thus consider the possibility of forest quality being modulated by land-use amount, type, and age. We assessed AGB in a densely farmed Brazilian region using a straightforward approach designed to be affordable at large scales, focusing on two expanding and contrasting land uses: sugarcane, and eucalyptus plantations. At a detailed scale, we confirmed through field surveys and AGB estimation using 3D-multispectral imagery (i.e., AGB = 0.842 × vegetation heightNDVI+1) that AGB variation could be predicted with forest degradation classes that are visually distinguishable with high-resolution images: 9.33 t ha-1 (90% predictive intervals [PI] = [3.23, 26.97]) in regenerating fields (RF), 31.12 t ha-1 (90% PI = [10.77, 89.90]) in pioneer woods (PW), and 149.04 t ha-1 (90% PI = [51.59, 430.58]) in dense forests (DF). Applying these values to land units sampled across the study region, we found an average land use of 88.5%, together with 11.5% of land set aside for conservation, which reduced AGB to less than 4.2% of its potential (averages of 5.85 t ha-1 in sugarcane-dominated areas and 6.56 t ha-1 in eucalyptus-dominated areas, with secondary forests averaging 149.04 t ha-1). This imbalance between forest cover and AGB resulted from forest quality decay, which was similarly severe among land-use types, ages, and extensions. Therefore, the shortage of trophic resources is likely more critical to wildlife than spatial limitations in vastly deforested tropical ecoregions, where AGB and carbon sinks can be more than doubled just by restoring forests in lands currently spared by agriculture.


Subject(s)
Ecosystem , Forests , Biomass , Conservation of Natural Resources , Agriculture , Trees
2.
Proc Biol Sci ; 290(1998): 20222450, 2023 05 10.
Article in English | MEDLINE | ID: mdl-37161334

ABSTRACT

Alien species are widely linked to biodiversity change, but the extent to which they are associated with the reshaping of ecological communities is not well understood. One possible mechanism is that assemblages where alien species are found exhibit elevated temporal turnover. To test this, we identified assemblages of vascular plants in the BioTIME database for those assemblages in which alien species are either present or absent and used the Jaccard measure to compute compositional dissimilarity between consecutive censuses. We found that, although alien species are typically rare in invaded assemblages, their presence is associated with an increase in the average rate of compositional change. These differences in compositional change between invaded and uninvaded assemblages are not linked to differences in species richness but rather to species replacement (turnover). Rapid compositional restructuring of assemblages is a major contributor to biodiversity change, and as such, our results suggest a role for alien species in bringing this about.


Subject(s)
Tracheophyta , Biodiversity , Databases, Factual , Introduced Species
3.
Biota Neotrop. (Online, Ed. ingl.) ; 23(3): e20221445, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1505832

ABSTRACT

Abstract Two species of Poaceae (Aristidoideae) Aristida ekmaniana Henrard and A. macrophylla Hack. considered "presumably extinct" in the Brazilian state of São Paulo were rediscovered during fieldwork. We hereby describe the location, ecosystem, and habitat type where the species were found. We suggest these grasses be removed from the list of extinct species and be placed in a category compatible with the current knowledge about their conservation status in the state of São Paulo.


Resumo Duas espécies de Poaceae (Aristidoideae), Aristida ekmaniana Henrard e A. macrophylla Hack., consideradas "presumivelmente extintas" no estado de São Paulo, Brasil, foram redescobertas durante trabalho em campo. Descrição, ilustração e observações ecológicas são apresentadas, incluindo locais de observação, ecossistemas e habitats. Sugerimos a revisão do status de conservação das espécies no estado de São Paulo.

4.
Biota Neotrop. (Online, Ed. ingl.) ; 22(spe): e20221407, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1403631

ABSTRACT

Abstract: Despite their negative environmental impacts, human-modified environments such as agricultural and urban landscapes can have a relevant role on biodiversity conservation as complements of protected areas. Such anthropized landscapes may have endangered, valuable, and nuisance species, although most of them do not fit in any of these categories. Therefore, in such environments we must deal with the same decision-making process concerning the same possible interventions proposed by Caughley (1994) to wildlife management, which are related to biological conservation, sustainable use, control/coexistence, and monitoring. Such decision-making process should be based on good science and good governance. On such context, the first step should be to implement multifunctional landscapes, which keep their primary mission of human use, but incorporate a second but fundamental mission of biological conservation. In this study we present a summary of the research carried out at the Biota Program of Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) in this field since the late 1990's and propose priorities for biodiversity research and governance in multifunctional landscapes for the near future.


Resumo Apesar de seus impactos ambientais negativos, ambientes modificados pelo homem, como paisagens agrícolas e urbanas, podem ter um papel relevante na conservação da biodiversidade como complementos de áreas protegidas. Tais paisagens antropizadas podem ter espécies ameaçadas, valiosas e incômodas, embora a maioria delas não se enquadre em nenhuma dessas categorias. Portanto, em tais ambientes devemos lidar com o mesmo processo de tomada de decisão sobre as mesmas possíveis intervenções propostas por Caughley (1994) para o manejo da vida selvagem, que estão relacionadas à conservação biológica, uso sustentável, controle/coexistência e monitoramento. Esse processo de tomada de decisão deve ser baseado em boa ciência e boa governança. Neste contexto, o primeiro passo deverá ser a implementação de paisagens multifuncionais, que mantenham a sua missão primordial de uso humano, mas que incorporem uma segunda, mas fundamental missão de conservação biológica. Neste estudo apresentamos um resumo das pesquisas realizadas no Programa Biota da Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) neste campo desde o final da década de 1990 e propomos prioridades para pesquisa e governança da biodiversidade em paisagens multifuncionais para o futuro próximo.

5.
Sci Total Environ ; 704: 135397, 2020 Feb 20.
Article in English | MEDLINE | ID: mdl-31810678

ABSTRACT

The Brazilian savanna (Cerrado) has been extensively converted to croplands, pastures and forestry plantations, and the deforestation frontier continues expanding. Land conversion may cause critical changes in soil functioning, yet very little is still known about the impact of Cerrado conversion on nutrient cycling and soil fertility. Here, we addressed this knowledge gap by investigating the effects of the woodland cerrado (cerradão) conversion into pastures and Eucalyptus plantations on nitrogen availability and mineralization potential, considering a wide range of spatial and temporal variability due to soil depth, site conditions, and seasonal variation. For three sites in São Paulo state and each of the target land cover types, we assessed the total N and inorganic N (NH4-N and NO3-N) pools, potentially mineralizable nitrogen (PMN) and soil urease activity in the first 2 m of the soil profile. Cerrado conversion to either pastures or Eucalyptus plantations significantly reduced NH4-N, while NO3-N showed similar values in Cerrado and Eucalyptus and lower values in pastures. We found a consistent pattern of lower N mineralization in the uppermost soil layers associated to Cerrado conversion, with decreases in PMN rate and urease activity. The soil below 30 cm depth showed no relevant changes. Considering the first 30 cm of the soil profile, the reduction in the stocks of inorganic N (NH4-N + NO3-N) ranged from ~14% for the conversion to Eucalyptus to ∽20% for the conversion to pasture. The impact of land conversion on N cycling surpassed the influence of the spatial (between-site) and seasonal variation. Overall, the results indicate a decline in available N and overall soil fertility due to Cerrado conversion, which could further increase N limitation in the Cerrado region, increase fertilization needs for future exploitation, and compromise the recovery of Cerrado in case of land abandonment or restoration.


Subject(s)
Agriculture , Conservation of Natural Resources , Ecosystem , Environmental Monitoring , Eucalyptus , Nitrogen/analysis , Brazil , Forestry , Forests , Grassland , Soil
6.
Environ Manage ; 55(6): 1377-89, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25860593

ABSTRACT

Strictly Protected Areas and riparian forests in Brazil are rarely large enough or connected enough to maintain viable populations of carnivores and animal movement over time, but these characteristics are fundamental for species conservation as they prevent the extinction of isolated animal populations. Therefore, the need to maintain connectivity for these species in human-dominated Atlantic landscapes is critical. In this study, we evaluated the landscape connectivity for large carnivores (cougar and jaguar) among the Strictly Protected Areas in the Atlantic Forest, evaluated the efficiency of the Mosaics of Protected Areas linked to land uses in promoting landscape connectivity, identified the critical habitat connections, and predicted the landscape connectivity status under the implementation of legislation for protecting riparian forests. The method was based on expert opinion translated into land use and land cover maps. The results show that the Protected Areas are still connected by a narrow band of landscape that is permeable to both species and that the Mosaics of Protected Areas increase the amount of protected area but fail to increase the connectivity between the forested mountain ranges (Serra do Mar and Serra da Mantiqueira). Riparian forests greatly increase connectivity, more than tripling the cougars' priority areas. We note that the selection of Brazilian protected areas still fails to create connectivity among the legally protected forest remnants. We recommend the immediate protection of the priority areas identified that would increase the structural landscape connectivity for these large carnivores, especially paths in the SE/NW direction between the two mountain ranges.


Subject(s)
Animal Migration , Conservation of Natural Resources/methods , Ecosystem , Forests , Panthera/growth & development , Puma/growth & development , Animals , Brazil , Humans
7.
Appl Plant Sci ; 3(2)2015 Feb.
Article in English | MEDLINE | ID: mdl-25699216

ABSTRACT

UNLABELLED: • PREMISE OF THE STUDY: We developed and validated microsatellite primers for Vellozia squamata (Velloziaceae), an endemic species of the cerrado (Brazilian savannas), to investigate the influence of different fire regimes on its genetic diversity and population structure. • METHODS AND RESULTS: Using a selective hybridization method, we tested 51 SSR loci using a natural population of V. squamata and obtained 47 amplifiable loci. Among these, 26 loci were polymorphic and the average values of genetic diversity were: average number of alleles per locus ([Formula: see text]) = 6.54, average number of alleles per polymorphic locus ([Formula: see text]) = 7.13, average observed heterozygosity [Formula: see text] = 0.22, average expected heterozygosity [Formula: see text] = 0.49, and average fixation index [Formula: see text] = 0.55. • CONCLUSIONS: These 26 loci allowed us to assess the effects of distinct fire regimes on the genetic structure of V. squamata populations with the aim of establishing strategies for the conservation of this endemic species. The markers can also be useful for future pharmaceutical studies, as the species has great potential for medicinal and cosmetic applications.

8.
Environ Manage ; 44(2): 346-55, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19536591

ABSTRACT

Prior to deforestation, São Paulo State had 79,000 km(2) covered by Cerrado (Brazilian savanna) physiognomies, but today less than 8.5% of this biodiversity hotspot remains, mostly in private lands. The global demand for agricultural goods has imposed strong pressure on natural areas, and the economic decisions of agribusiness managers are crucial to the fate of Cerrado domain remaining areas (CDRA) in Brazil. Our aim was to investigate the effectiveness of Brazilian private protected areas policy, and to propose a feasible alternative to promote CDRA protection. This article assessed the main agribusiness opportunity costs for natural areas preservation: the land use profitability and the arable land price. The CDRA percentage and the opportunity costs were estimated for 349 municipal districts of São Paulo State through secondary spatial data and profitability values of 38 main agricultural products. We found that Brazilian private protected areas policy fails to preserve CDRA, although the values of non-compliance fines were higher than average opportunity costs. The scenario with very restrictive laws on private protected areas and historical high interest rates allowed us to conceive a feasible cross compliance proposal to improve environmental and agricultural policies.


Subject(s)
Conservation of Natural Resources/economics , Brazil , Conservation of Natural Resources/legislation & jurisprudence , Private Sector
11.
Braz. arch. biol. technol ; 51(4): 625-631, June-Aug. 2008. ilus, tab
Article in English | LILACS | ID: lil-622670

ABSTRACT

The aim of this study was to look for evidence of allelochemicals in B. decumbens, in parts of the plant from where they could easily be released to the environment. The germination inhibition of Phalaris canariensis, Lactuca sativa (standard species) and Melinis minutiflora, another invasive African grass, was tested using B. decumbens germinating seeds and aqueous leachates of the roots, green and senescent leaves, at 5, 10 and 20% w/v. Both the germinating seeds and the aqueous leachates of B. decumbens reduced the germination of the species tested; the effectiveness of the aqueous leachates increased according to concentration. Apparently, the competitive advantage of B. decumbens in the cerrados could be amplified via allelopathy.


Invasão biológica é uma das maiores causas atuais da perda de biodiversidade. Várias espécies que se tornam invasoras produzem substâncias fitotóxicas que aumentam sua capacidade competitiva; assim, a alelopatia é uma estratégia capaz de potencializar o sucesso de invasão. Brachiaria decumbens, uma gramínea africana, invadiu os cerrados brasileiros e representa, atualmente, uma séria ameaça à biota regional. Neste ensaio, verificamos a presença de aleloquímicos em partes de B. decumbens das quais poderiam ser facilmente liberados para o ambiente. Testamos a inibição da germinação de Phalaris canariensis, Lactuca sativa (espécies padrão) e Melinis minutiflora (outra gramínea africana invasora) usando sementes de B. decumbens e soluções aquosas lixiviadas de suas raízes, folhas verdes e folhas senescentes, a 5, 10 e 20% de peso do material por volume de água. Tanto as sementes como as soluções lixiviadas de decumbens reduziram a germinação das outras espécies; a eficiência dos lixiviados aumentou de acordo com a concentração da solução. Acreditamos que a grande vantagem competitiva de B. decumbens no cerrado possa ser amplificada pela alelopatia.

12.
Comp Biochem Physiol A Mol Integr Physiol ; 147(3): 586-593, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17321770

ABSTRACT

Brazil stood out as the country with the highest number of submissions to the editorial project dedicated to Latin America by the journal Comparative Biochemistry and Physiology. Therefore, we felt that it was important to critically discuss the state of comparative biochemistry and physiology in this country. Our study is based on data collected from the ISI Web-of-Science. We analyzed publication trends through time, availability of novel approaches and techniques, patterns of collaboration among different geographical regions, patterns of collaboration with researchers abroad, and relative efforts dedicated to the study of biochemical and physiological adaptation of native fauna representing different terrestrial Brazilian biomes. Overall, our data shows that comparative biochemistry and physiology is a lively and productive discipline, but that some biases limit the scope of the field in Brazil. Some important limitations are the very heterogeneous distribution of research nuclei throughout the country and the absence of some important approaches, such as remote sensing and the use of molecular biology techniques in a comparative or evolutionary context. We also noticed that international collaboration far surpasses interregional collaboration, and discuss the possible causes and consequences of this situation. Finally, we found that Brazilian comparative biochemistry and physiology is biome-biased, as the Amazonian fauna has received far more attention than the whole pool of fauna representing other terrestrial biomes. We discuss the possible causes of these biases, and propose some directions that may contribute to invigorate the field in the country.


Subject(s)
Biochemistry , Physiology, Comparative , Animals , Biochemical Phenomena , Brazil , Cooperative Behavior , Geography , International Cooperation , Publishing
13.
Biota neotrop. (Online, Ed. port.) ; 7(3): 21-29, 2007. ilus, tab
Article in Portuguese | LILACS | ID: lil-477669

ABSTRACT

A Ecologia de Paisagens busca entender a influência da heterogeneidade espacial do meio em processos ecológicos, enfatizando as ações do homem sobre o meio, ou o contexto espacial sobre as populações. É uma ciência recente, que ainda está solidificando conceitos, mas que se utiliza fortemente dos avanços tecnológicos em sensoriamento remoto e sistemas de informação geográfica. Com o objetivo de verificar os principais temas, abordagens metodológicas e técnicas de análise que estão sendo seguidas em Ecologia de Paisagens no Brasil, bem como as instituições de pesquisa envolvidas, fizemos um levantamento analisando os resumos de trabalhos científicos em Ecologia de Paisagens apresentados nas principais reuniões científicas nacionais que abordaram esse assunto, realizadas entre 2000 e 2005, e também analisamos os resumos das dissertações e teses produzidas entre 2000 e 2004. Os resumos foram classificados conforme a temática (7 temas), abordagem metodológica (7 abordagens) e técnicas de análise utilizadas (5 técnicas). Dos 226 resumos de congressos e 222 dissertações e teses analisados, a maioria tratou da descrição de padrões espaciais, da relação entre padrões e processos e de planejamento ambiental. Predominou a abordagem observacional-descritiva e o uso de técnicas qualitativas ou quantificações simples (medições e porcentagens). Menos de 20 por cento dos estudos utilizaram técnicas quantitativas, numa abordagem observacional-experimental, contudo, houve uma tendência crescente ao emprego de abordagens quantitativas. Foi notada uma baixa correspondência entre as instituições de pesquisa onde as dissertações e teses foram produzidas, as instituições representadas nos congressos e aquelas catalogadas nos grupos de pesquisa do CNPq. Constatamos também que a participação brasileira na produção científica mundial em Ecologia de Paisagens ainda é muito pequena, provavelmente devido ao caráter predominantemente descritivo...


Landscape Ecology seeks to understand the influence of environmental spatial heterogeneity on ecological processes, emphasizing human actions on the environment or the spatial context on biological species. It is a new science still consolidating concepts which makes strong use of technological improvements in remote sensing and geographical information systems. Aiming at verifying the main themes, methodological approaches and techniques that are being used in Landscape Ecology in Brazil, as well as the research institutes involved, we carried out a survey and analyzed the abstracts on Landscape Ecology researches submitted to the main national scientific meetings where this subject was discussed (years 2000-2005), and the abstracts of MSc and PhD theses produced from 2000 to 2004. The abstracts were classified according to 7 themes, 7 methodological approaches and 5 techniques of analysis. We analyzed 226 congress abstracts and 222 theses abstracts, from which most dealt with the description of spatial patterns, the relationships between patterns and processes, and environmental planning. A descriptive approach and the use of qualitative techniques or simple quantifications (measurements and percentages) prevailed. Less than 20 percent of the studies used quantitative techniques under an experimental approach, but a growing tendency on the use of quantitative procedures was verified throughout the years. Comparing both the research institutes where the theses were produced and those represented in the meetings with the research institutes which appear in the CNPq research groups database we noticed a low correspondence among them. We also verified that the Brazilian contribution in the Landscape Ecology scientific production worldwide is still very small, probably due to the prevailing descriptive nature of the current researches. We believe that the growth of Brazilian research in Landscape Ecology must go beyond the description of...


Subject(s)
Biological Phenomena/analysis , Trees/classification , Comparative Study , Man-Made Disasters/analysis , Man-Made Disasters/classification , Ecology/classification , Review
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