RESUMO
The Payment for Environmental Services (PES) is often conceived through complex schemes without a clear definition of all concepts involved. This study presents the results of a systematic literature review on PES schemes in Brazil, accompanied by a critical assessment of their efficacy for potential environmental gains. The PES approaches were grouped into six categories based on the research focus, and those that were focused on PES policies were identified as the most studied. A particular emphasis has been given to the Amazon and Atlantic Forest biomes, where the ecosystem services studied were mostly centered on issues related to carbon and water, respectively. Approximately one-third of all schemes provided no clear definition of which ecosystem services are proposed for payment. In addition, the review showed no consensus among studies on the definition of services in similar schemes. Most schemes presented no payment system conditioned on the provision of environmental services. Furthermore, the review showed that the absence of clarity in the application of concepts may hinder the development of public policies to properly implement PES in Brazil. The conclusion is that standardizing terms used in the literature and in PES schemes is critical; therefore, the use of the Common International Classification of Ecosystem Services (CICES) as a reference is recommended to ensure clarity, objectivity and, more importantly, the expected environmental efficacy.
RESUMO
RESUMO O número de municípios e estados brasileiros que estão aderindo ao pagamento por serviços ambientais (PSA) vem crescendo ao longo dos últimos anos. Por meio de uma pesquisa documental e científica, buscou-se compreender a evolução de quase 20 anos de experiências brasileiras em PSA hídricos. A investigação foi fundamentada em um inventário das iniciativas (já encerradas ou em desenvolvimento), de sua localização, da base legal e dos métodos de valoração. Considerando o universo amostral de 68 iniciativas brasileiras de PSA hídricos, observaram-se: maior concentração dos programas no sul e sudeste, com tendência à expansão para as demais regiões brasileiras, especialmente a Centro-Oeste; e as primeiras iniciativas de PSA hídricos do Brasil adotavam o pagamento por valor fixo, sem a consideração da qualidade biótica das propriedades rurais, padrão que foi gradualmente substituído pelo cálculo do custo de oportunidade da terra e pela inclusão de indicadores físico-ambientais e socioeconômicos nas metodologias de valoração. O estudo permite concluir que, na última década, existe a tendência de os programas de PSA hídricos adotarem metodologias com abordagem interdisciplinar e sistêmica para valoração da provisão de serviços ambientais.
ABSTRACT The number of Brazilian municipalities and states engaging in payment for environmental services (PES) has been increasing over the last few years. Through a documentary and scientific research, we sought to understand the evolution of almost 20 years of Brazilian experiences in hydrological PES. The research was based on an inventory of the initiatives (already finished or under development), their location, legal basis, and valuation methods. Considering the sampling universe of 68 Brazilian hydrological PES initiatives, we observed: higher concentration of programs in the South and Southeast, with a tendency to expand them to other Brazilian regions, especially the Midwest; the first initiatives of hydrological PES in Brazil adopted the payment of a fixed value, without considering the biotic quality of the rural properties, a pattern which was gradually replaced by the calculation of the opportunity cost of land and the inclusion of physical-environmental indicators and socioeconomic factors in the valuation methodologies. The study allows to conclude that, in the last decade, there has been a tendency for hydrological PES programs to adopt methodologies with an interdisciplinary and systemic approach to assess the provision of environmental services.
RESUMO
Avermectins (AVM) are macrocyclic lactones used in livestock and agriculture. A quantitative method of high performance liquid chromatography with fluorescence detection for the determination of eprinomectin, abamectin, doramectin and ivermectin in rural water samples was developed and validated. The method was employed to study samples collected in the Pito Aceso River microbasin, located in the Bom Jardim municipality, Rio de Janeiro State, Brazil. Samples were extracted by solid phase extraction using a polymeric stationary phase, the eluted fraction was re-concentrated under a gentle N2 flow and derivatized to allow AVM determination using liquid chromatography with fluorescence detection. The excitation and emission wavelengths of the derivatives were 365 and 470nm, respectively, and a total chromatographic run of 12min was achieved. Very low limits of quantification (22-58ngL(-1)) were found after re-concentration using N2. Recovery values varied from 85.7% to 119.2% with standard deviations between 1.2% and 10.2%. The validated method was applied in the determination of AVM in 15 water samples collected in the Pito Aceso River microbasin, but most of them were free of AVM or showed only trace levels of these compounds, except for a sample that contained doramectin (9.11µgL(-1)). The method is suitable for routine analysis with satisfactory recovery, sensitivity, and selectivity.
