A tutela jurídica da biodiversidade no Brasil e na Colômbia pós-1992:: considerações e perspectivas atuais

The article analyses how Brazilian and Colombian legal systems deal with the protection of their biodiversity, especially after both joined the Convention on Biological Diversity (CBD) during the RIO-92 Conference. Being one of the fundamental properties of nature, biodiversity is of interest of national states, not only for the use of their natural assets, but also for protection and conservation purposes. In this study, a survey of the principles and guidelines of the CBD was carried out. The internal regulations of each country were also taken into consideration. We conclude that, in spite of their previous environmental regulations, dating from before 1992, both countries fostered the evolution of their regiments on biodiversity after the CBD. However, and as it happens with other international agreements, the Convention’s Commandments still find it difficult to be effectively applied. Scientific evidence shows that local fauna, flora and the environment as a whole are still in need of legal protection. The effective implementtion of actions for the conservation of biological diversity is still unclear.O artigo apresenta como os ordenamentos jurídicos brasileiros e colombianos abordam a tutela da biodiversidade, sobretudo após a aderência de ambos à Convenção da Diversidade Biológica (CDB), durante a Conferência RIO-92. A biodiversidade é um dos fundamentos da natureza e seus recursos despertam o interesse dos Estados, não somente para o aproveitamento de seus patrimônios naturais, mas para proteção e conservação. Realizou-se um levantamento dos princípios e diretrizes da Convenção, apresentando as regulamentações internas de cada país. Concluiu-se que, apesar de apresentarem regulamentações ambientais antes de 1992, os dois países evoluíram seus regimentos sobre biodiversidade após a CDB, todavia, similarmente a outros acordos internacionais, a convenção tem dificuldade em avançar no que diz respeito à efetividade de seus mandamentos. Há exemplos claros de que a fauna, a flora e o meio ambiente como um todo carecem de mais suporte, expondo que as ações efetivas de conservação da diversidade biológica ainda não são evidentes

Evaluation of areas with environmental vulnerability in the Rio Claro hydrographic basin, SP – Brazil/Avaliação de áreas com vulnerabilidade ambiental na bacia hidrográfica do Rio Claro, SP - Brasil

The environmental vulnerability study is one of the most important ways to analyze the anthropic pressures that occur in the physical and biological environment. In this context, the aim of this work is to evaluate the areas with environmental vulnerability in the Rio Claro Hydrographic Basin in 2001 and 2017, using physical and biological factors. The hydrographic basin has 251.91km² and is localized in the Santa Rita do Passa Quatro (SP). The analysis was carried out addressing the physical attributes (slope, geology, unconsolidated materials, and aquifer units) and biological attributes with use and land cover for 2001 and 2017. The methodology was based on the environmental characterization and standardization of the information through the Fuzzy logic, processed in ArcGIS 10.5 software. The data were classified into five levels of environmental vulnerability (very low, low, medium, high and very high). For both periods, the most evident levels were the low, medium and high vulnerability, occupying over 70%. The method employed in this work allowed the evaluation of the environmental vulnerability in the Rio Claro Hydrographic Basin and made possible the definition of the regions that suffered interference due to the influence of the anthropic activities in the physical and biological environment, as well as of the different activities that occurred in the region.

Different methodological approaches to natural vulnerability to erosion in southeastern Brazil / Diferentes abordagens metodológicas da vulnerabilidade natural à erosão no sudeste do Brasil

The natural vulnerability addresses the processes of morphogenesis and pedogenesis integrating information related to the rocky substrate, soils, geomorphology, vegetation. The study of natural variability is essential for understanding ecosystems in the face of change processes in the environment. This work aimed to analyze the natural vulnerability to the occurrence of erosion, adopting a method based on Crepani and Analysis Hierarchical Process (AHP) method in the Rio Claro Watershed - São Paulo - Brasil. Four information plans were used in the 1:50000 scale, being: geomorphology, pedology, geology and vegetation/anthropic intervention. The Natural Vulnerability to Erosion Chart is classified into five classes (Very Low, Low, Average, High, and Very High). Comparing the charts generated by the two methods based on Crepani et al. (2001) and Saaty (1980), there was a difference in the Very Low and High vulnerability classes. The most evident class in both charts is the average vulnerability, corresponding 94.55km² of the area in Crepani Method chart, and 93.34km² in AHP Method chart, followed by the “Low” class corresponding of 55.56km² and 76.67% respectively the Crepani and AHP methods. For the "High" class there was a decrease of 48.28% when compared to the two cards, the "Very high" class suffered the least change (-0.09%), while the "Very low" class increased above 100%. The methods employed allowed the generation of results that show the reality of the study area, it is worth mentioning that the Crepani method is more generic because it considers the similarity of the information plans for the vulnerability analysis, whereas the AHP method presents the advantage of hierarchizing both information plans and their classes, highlighting the relative importance of natural vulnerability to erosion.

Species effects on litter decomposition and N transfer between leaves in mixed plantation of Eucalyptus grandis and Acacia mangium

As espécies fixadoras de nitrogênio (N) são utilizadas junto às plantações florestais com o objetivo de incremento de N. Entretanto quando essas espécies são inseridas à monocultura acorre interferência na formação da serapilheira e, consequentemente, a ciclagem de nutrientes do sistema. O estudo foi desenvolvido em plantios puros e mistos de Eucalyptus grandis e Acacia mangium na Estação Experimental de Ciências Florestais da ESALQ- USP, em Itatinga - SP. O presente trabalho constitui de dois experimentos utilizando a técnica in situ de bolsas de decomposição e teve como objetivos: a) avaliar a dinâmica de decomposição de folhas e raízes finas de E. grandis e A. mangium em diferentes plantios e qual a influência da composição química do material vegetal e do solo na ciclagem de nutrientes, a \"teoria da vantagem doméstica\"; b) estudar a ciclagem de nutrientes em plantios consorciados através da determinação da composição química e a qualidade do material vegetal em decomposição; c) estimar a transferência bruta e líquida de nitrogênio durante a decomposição de folhas na mistura das duas espécies, com a finalidade de entender as interações ecológicas no consórcio do eucalipto com leguminosa. A decomposição de folhas e raízes das duas espécies estudadas apresentaram dinâmicas distintas de perdas de massa: as folhas de eucalipto (FE) decompõem mais rápido que as de acácia (FA), já as raízes não apresentaram diferenças entre raízes de acácia (RA) e raízes de eucalipto (RE). A quantidade inicial de N não influenciou na decomposição do material e houve imobilização deste elemento durante o período. A relação C/N não foi eficiente como parâmetro de decomposição, pois o valor de C/N para FA foi o dobro de FE. A relação N/P apresentou uma evolução durante o experimento, tanto para folhas quanto para raízes e pode predizer características da comunidade microbiana, maior prevalência de bactérias ou fungos. A lignina demonstrou-se como o componente químico responsável pelo padrão de decomposição encontrado, pois após um ano não alterou sua concentração nas folhas. A transferência de N foi dirigida pela qualidade da folha dreno e não pela fonte, assim FA foi o tipo de folha que recebeu mais N das folhas em que foram pareadas, principalmente com FE. Esses resultados demonstram que embora o material do eucalipto seja considerado recalcitrante, após sucessivos anos de manejo desta espécie na área a comunidade microbiana do solo foi favorável a melhor decomposição deste material que o material da acácia, mesmo em segunda rotação desta culturaThe nitrogen-fixing species (N) are used with forest plantations to increase N. However when these species are inserted monoculture rushes to interference in the formation of litter, and thus the nutrient cycling of the system. The study was conducted in pure and mixed plantations of Eucalyptus grandis and Acacia mangium in the Experimental Station of Forest Sciences ESALQ-USP in Itatinga - SP. This work consists of two experiments using litterbags technique to assess the decomposition and were aimed at: a) evaluate the dynamics of decomposing leaves and fine roots of E. grandis and A. mangium plantations in different and what influence the chemical composition of plant material and soil nutrient cycling in the \"home advantage theory\", b) study the cycling of nutrients in plantations syndicated by determining the chemical composition and quality of material decaying plant c) estimate the gross and net transfer of nitrogen during decomposition of leaves of the mixture of the two species, in order to understand the ecological interactions in the consortium of eucalyptus and legumes. The decomposition of leaves and roots of both species showed distinct dynamics of mass loss: eucalyptus leaves (LE) decomposer faster than acacia (LA), since the roots did not differ among acacia roots (RA) and eucalyptus roots (RE). The initial amount of N had no influence on the decomposition of material there and immobilization element during this period. The C / N was not effective as a parameter of decomposition, because the value of C / N for AF is twice the FE. The N / P ratio had changed during the experiment, both for leaves and for roots and can predict characteristics of the microbial community, the greater prevalence of bacteria or fungi. The lignin was shown as the chemical component responsible for the pattern of decay found, because after one year did not alter its concentration in the leaves. The transfer of N was driven by the quality of the sheet drain and not the source, than LA was the type of leaf that received more N in the leaves that were paired primarily with LE. These results demonstrate that although the material is eucalyptus considered recalcitrant, after successive years of management of this species in the soil microbial community was in favor of better decomposition of this material as the material of the acacia, even in this second rotation cro

Tree species effects on topsoil carbon stock and concentration are mediated by tree species type, mycorrhizal association, and N-fixing ability at the global scale

Selection of appropriate tree species is an important forest management decision that may affect sequestration of carbon (C) in soil. However, information about tree species effects on soil C stocks at the global scale remains unclear. Here, we quantitatively synthesized 850 observations from field studies that were conducted in a common garden or monoculture plantations to assess how tree species type (broadleaf vs. conifer), mycorrhizal association (arbuscular mycorrhizal (AM) vs. ectomycorrhizal (ECM)), and N-fixing ability (N-fixing vs. non-N-fixing), directly and indirectly, affect topsoil (with a median depth of 10 cm) C concentration and stock, and how such effects were influenced by environmental factors such as geographical location and climate. We found that (1) tree species type, mycorrhizal association, and N-fixing ability were all important factors affecting soil C, with lower forest floor C stocks under broadleaved (44%), AM (39%), or N-fixing (28%) trees respectively, but higher mineral soil C concentration (11%, 22%, and 156%) and stock (9%, 10%, and 6%) under broadleaved, AM, and N-fixing trees respectively; (2) tree species type, mycorrhizal association, and N-fixing ability affected forest floor C stock and mineral soil C concentration and stock directly or indirectly through impacting soil properties such as microbial biomass C and nitrogen; (3) tree species effects on mineral soil C concentration and stock were mediated by latitude, MAT, MAP, and forest stand age. These results reveal how tree species and their specific traits influence forest floor C stock and mineral soil C concentration and stock at a global scale. Insights into the underlying mechanisms of tree species effects found in our study would be useful to inform tree species selection in forest management or afforestation aiming to sequester more atmospheric C in soil for mitigation of climate change.Comment: Authors Accepted Manuscrip

Litter quality, mycorrhizal association, and soil properties regulate effects of tree species on the soil fauna community

Forest management, including selection of appropriate tree species to mitigate climate change and sustain biodiversity, requires a better understanding of factors that affect the composition of soil fauna communities. These communities are an integral part of the soil ecosystem and play an essential role in forest ecosystem functioning related to carbon and nitrogen cycling. Here, by performing a field study across six common gardens in Denmark, we evaluated the effects of tree species identity and mycorrhizal association (i.e., arbuscular mycorrhiza (AM) and ectomycorrhiza (ECM)) on soil fauna (meso- and macrofauna) taxonomic and functional community composition by using diversity, abundance, and biomass as proxies. We found that (1) tree species identity and mycorrhizal association both showed significant effects on soil fauna communities, but the separation between community characteristics in AM and ECM tree species was not entirely consistent; (2) total soil fauna abundance, biomass, as well as taxonomic and functional diversity were generally significantly higher under AM tree species, as well as lime, with higher litter quality (high N and base cation and low lignin:N ratio); (3) tree species significantly influenced the properties of litter, forest floor, and soil, among which litter and/or forest floor N, P, Ca, and Mg concentrations, soil pH, and soil moisture predominantly affected soil fauna abundance, biomass, and taxonomic and functional diversity. Our results from this multisite common garden experiment provide strong and consistent evidence of positive effects of tree species with higher litter quality on soil fauna communities in general, which helps to better understand the effects of tree species selection on soil biodiversity and its functions related to forest soil carbon sequestration

Deco<em></em>mposition of <em>Eucalyptus grandis</em> and <em>Acacia mangium</em> leaves and fine roots in tropical conditions did not meet the home field Advantage hypothesis

International audienceUnlike Eucalyptus monocultures, nitrogen fixing trees are likely to improve the soil nutrient status through the decomposition of N-enriched litter. The Home Field Advantage (HFA) hypothesis states that plants can create conditions that increase the decomposition rates of their own litter. However, there may not be any HFA when most of the decomposers are generalists. A reciprocal transplant decomposition experiment of fine roots and leaves of Acacia mangium and Eucalyptus grandis was undertaken in monocultures of these two species to test the HFA hypothesis using a complete randomized design with three blocks. Three litterbags containing leaf or fine root residues of each species were collected every 3 months from each plot over 12 months for fine roots and 24 months for leaves. The litter mass and C, N and P concentrations were measured at each sampling date. The concentrations of C-compounds were measured 0, 12 and 24 months from the start of the experiment. There was no evidence of HFA for either the leaves or the fine roots of either species. The decomposition rates were slower for Acacia litter than for Eucalyptus litter even though initial N concentrations were 1.9-2.9 times higher and P concentrations were 1.5-3.3 times higher in the Acacia residues. N:P ratios were greater than 20-30 for the residues of both species, with the highest values for Acacia. Litter decomposition depended partly on the C quality of the litter, primarily in terms of water soluble compounds and lignin content. As shown recently in tropical rainforests, these results suggest that the activity of decomposers is limited by energy starvation in tropical planted forests. Decomposer activity may also have been limited by P availability which may not have been directly related to the P concentrations or C:P ratios in the residues