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This study describes a collaborative modeling process deployed at the Cantareira Water Supply System (CWSS) in São Paulo City Metropolitan Area, Brazil. The CWSS faces challenges for meeting the increasing water demand, while land-use and climate change and their combined effect on its water cycle and balance have created a complex water resources management problem. Through a stakeholder engagement process—involving scientists and policymakers, the water utility company, and state administration—environmental simulation models were developed to elicit and represent multiple environmental, economic, and policy perspectives, developing a mutual language to communicate and establish common goals of water resources management. Study outputs include estimation of biophysical and economic benefits associated with prioritized native vegetation restoration activities in the source watersheds. These outputs are deployed in support of landscape planning and the decision process integrating multiple stakeholder perspectives in São Paulo state administration, the water utility company, and municipalities.

In order to understand the hydrological impacts of the nature-based solutions in the Cantareira Water Supply System, this study evaluates six different land cover and land use change scenarios. The first and second consider the restoration of native vegetation in riparian areas, the third prioritizes restoration sites using biophysical characteristics (optimized restoration scenario derived from Resource Investment Optimization System—RIOS), the fourth considers best management practices and the fifth and sixth are hypothetical extreme scenarios converting all pasture to forest and vice versa. Two hydrological models were developed to represent the distributions of water and yields in the study watershed: HEC-HMS and SWAT. Simulation results indicate that when nature-based solutions are implemented, surface runoff is reduced and ambient storage increases during the rainy season (December–March); while the overall flow increases during the dry season (June–September). The combination of specific hydrologic components of RIOS-customized intervention scenario simulation outputs—namely surface flows and groundwater contribution to stream flows—indicate on average 33% increase in the overall water yield, or 206 hm3/year, across the study watershed when comparing against the baseline conditions. In the same modeling scenario, the water storage in the sub-watersheds adjacent to the reservoirs showed an increase of 58% (or 341 hm3/year). The results indicate that adopting NbS in the source watershed can mitigate the impacts of extreme drought conditions and contribute toward building long-term water security.

Despite its rich water resources, Brazil is increasingly facing extreme hydrologic events such as droughts and floods. The Sao Paulo Cantareira water supply system (CWSS) offers an opportunity to examine the potential economic benefits of nature-based solutions (NbS) to improve water security and reduce the economic cost of drought. This study explores the potential benefits under a counterfactual NbS land-use scenario compared to actual land use and assesses the economic viability of NbS investments in the CWSS. Specifically, we estimate the economic cost of the 2014–2015 drought in Sao Paulo state for the industrial and water sectors served by the CWSS. We estimate the potential avoided costs under the NbS scenario and conduct a cost–benefit analysis of the NbS scenario investments, including both water supply and carbon sequestration benefits. We estimate that the economic losses of this single drought event totaled BRL 1.6 billion. If NbS had been implemented, this cost could have been reduced by 28%. A cost–benefit analysis that includes only the water supply or both the water supply and carbon sequestration benefits indicates that the NbS scenario has a positive net present value of BRL 144 million and BRL 632 million, respectively. Thus, our results highlight the economic viability of the hypothetical NbS investment in mitigating extreme climatic events.

Investments in watershed services programs hold the promise to protect and restore ecosystems and water resources. The design and implementation of such programs is often accompanied by hydrologic modeling and monitoring, although the role of hydrologic information in meeting the needs of program managers remains unclear. In the Camboriu watershed, Brazil, we explored the value of hydrologic modeling and monitoring with respect to two dimensions: scientific credibility and use of generated knowledge in the design, implementation, and evaluation of the watershed management program. We used a combination of semi-structured interviews, focus groups, and hydrologic modeling under various levels of data availability to examine when improved models and data availability might build credibility and provide more useful information for decision makers. We found that hydrologic information was not actually used for the detailed design, but rather contributed to broad-scale support of the program by increasing scientific credibility. Model sophistication and data availability improved the credibility of hydrologic information but did not affect actual decisions related to program design. Hydrologic monitoring data were critical for model calibration, and high-resolution land use and land cover data, obtained via remote sensing, affected some model outputs which were not used to design the program. Our study suggests that identifying how hydrologic data will inform decision making should guide the level of effort used in hydrologic modeling and monitoring.

Water funds seek to promote long-term watershed conservation with multiple benefits for biodiversity and human well-being. This approach has grown rapidly, particularly in Latin America where more than 30 water funds were in operation or development by 2014. To meet the need for evidence to guide ongoing decisions, we assessed the goals and strategies of 16 programs that were operating in 2013–2014 in association with the Latin American Water Funds Partnership. Our findings underscore the diversity within this approach to investment in watershed services. The various financial, governance, and management mechanisms adopted by these programs reflected their distinct biophysical, socio-economic, and political contexts. All 16 water funds aimed to secure water quality (15/16) and/or quantity (including the timing of flows) (14/16). The majority of programs also explicitly strived for co-benefits to local livelihoods (9/16) and biodiversity (11/16). Public funding secured through legislation provided the most funding to date, but private, NGO, and development bank source were also important for some programs. While programs have actively engaged rural land stewards, this stakeholder group was represented on governance boards in just 4 of 16 funds. Additionally, while the majority of water funds with activities on the ground (13/16) reported biophysical and social impact monitoring (8/16), many faced significant logistical, technical, and funding challenges to its implementation. We recommend greater inclusion of rural land stewards on governance boards, increased engagement of the private sector, and a sustained commitment to an evidence-based approach to increase the likelihood that programs will attain their goals.

A população mundial deverá atingir 9 bilhões de pessoas em 2050 e colocará maior pressão sobre os recursos naturais para garantir o atendimento das necessidades nutricionais e conforto desse grande contingente populacional. Inúmeros investimentos em pesquisas agropecuárias, medicina, fontes energéticas, tecnologias de materiais, políticas para redução da pobreza e estratégias de desenvolvimento sustentável estão em curso para atender esta previsão. Ações para a conservação dos recursos naturais e dos serviços ambientais estão implícitas nas estratégias de desenvolvimento sustentável. Observa-se um aumento no número de políticas públicas implementadas, resultados alcançados, projetos em curso e pesquisas relacionados à conservação ambiental, comprovando a sua relevância atual e para o futuro. Artigo bilíngue, escrito em português e inglês.

Sensitive biological responses to environmental contaminants are useful as early warning signals to predict the damages by long-term exposure. Protocols standardization to quantify biochemical parameters in different fish species is required to validate its use as biomarkers. Comparative studies from different fish species and its interpretation are a challenge for the validation of its use as general biomarkers, representative of environmental impact. In this study, the protocol for liver cytochrome P450 (CYP) analysis from the native Brazilian fish Ancistrus multispinis was established. The microsome contamination by hemoglobin during the analysis of CYP in liver was detected, leading to misinterpretation of the results. The spectrophotometric method for CYP analysis was adapted in order to diminish the hemoglobin interference. Additionally, the western blotting method for CYP1A analysis was tested with success for this fish species.Respostas biológicas sensíveis aos contaminantes ambientais são úteis para prever efeitos prejudiciais devido a exposições crônicas. Padronização de protocolos para quantificar parâmetros bioquímicos em diferentes espécies de peixes é necessária para validar o uso como biomarcador. Estudos comparativos de diferentes espécies de peixe e sua interpretação são um avanço para a validação do uso de biomarcadores gerais, representativos do impacto ambiental. Neste estudo o protocolo para a análise do citocromo P450 (CYP) do peixe nativo brasileiro Ancistrus multispinis foi estabelecido. Cyp é um biomarcador de exposição principalmente de hidrocarbonetos policíclicos aromáticos (HAP), bifenilas policloradas (PCB) e dioxinas. A contaminação do microssomo pela hemoglobina durante as análises do CYP no fígado foi detectada, levando a uma interpretação errônea dos resultados. O método espectrofotométrico para análise do CYP foi adaptado para diminuir a interferência da hemoglobina. Além disso, o método de western blotting para análise de CYP1A foi testado com sucesso para essa espécie de peixe.

This study aimed to determine the effect of sublethal doses of deltamethrin, using biochemical biomarkers as activities of cholinesterase (ChE), ethoxyresorufin-O-deethylase (EROD) and the Na + K + - ATPase and levels of total cytochrome P450 (CYP450). Fishes received sublethal doses of deltamethrin and were sacrificed after 96 h of exposure. Samples of gills, heart, brain, liver and muscle were collected for enzymatic analyses. Deltamethrin inhibited the activity of the gills and heart Na + K + -ATPase, induced the liver total CYP450, as well as the liver EROD activity. The activity of the ChE was not inhibited by deltamethrin. Deltamethrin altered the hepatic metabolism and the normal ionic flux in Ancistrus multispinis . Key words: deltamethrin, cytochrome P450, fish, Ancistrus multispinis , biomarker * Author for correspondence: helassis@ufpr.br INTRODUCTION Pyrethroids are synthetic derivatives of pyrethrins, which are toxic components contained in the flowers of Chrysanthemum cinerariaefolium . Although synthetic pyrethroids are less persistent and less toxic to mammals and birds (Sayeed et al, 2003), they are highly toxic to a number of non-target organisms such as bees, freshwater fish and other aquatic organisms even at very low concentrations (Oudou et al, 2004). For this reason, these organisms are extremely sensitive to neurotoxic effects of pyrethroids when they reach surface water-courses (Bradbury and Coats 1989, Haya, 1989; Mittal et al, 1994). One of the pyrethroids that has found wide acceptability and is extremely used in agriculture and forestry because of its high activity against a broad spectrum of insect pests (Villarini et al, 1998) is deltamethrin ((S) α-cyano-3-phenoxybenzyl-(1R)-cis-3-(2.2-dibromovinyl)-2,2- dimethyl cyclopropane carboxylate). However, its effects on nervous, respiratory, and hematological systems in fishes have been reported (Ural and Sa glam, 2005, Pimpao et al, 2007). Balint et al (1995) observed 20% decrease in acetylcholinesterase activity of brain, heart, blood, liver and skeletal muscle of carp after the 3 days exposure to deltamethrin. In rats, the main reaction involved in the metabolism of deltamethrin is ester cleavage, by CYP450 and carboxyesterase action. Metabolism in fish is largely oxidative and deficient in esterases metabolization (Demoute, 1989). ATPase has been demonstrated to be one of the targets of pyrethroids. Some authors showed that ATPase including cell membrane-associated

This study is aimed at evaluating the sublethal effects of endosulfan (EDS) in juvenile common carp (Cyprinus carpio). For this purpose, fish were exposed for 15 days to the technical EDS (95% pure) diluted in dimethyl sulfoxide (DMSO) 0.1% of the total volume in water solution in a semi-static system at sublethal concentration (1 μg/L). Subsequently, the liver somatic index (LSI) and factor condition (K) were determined. The total cytocrome P450 (CYP), CYP1A isoform, and the ethoxyresorufin-O-deethylase (EROD) activity were determined from the hepatic microsomal fraction as well as the activity of the oxidative stress enzyme system such as superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione peroxidase (GP(X)), glutathione reductase (GR), and glucose-6-phosphate dehydrogenase (G6PDH). Among the parameters assessed, EDS at the sublethal concentration in subchronic exposure caused significant changes in liver somatic indices as well as induction of the phase I biotransformation system and oxidative stress in juvenile common carp (Cyprinus carpio). Thus, it is seen that the use of biochemical biomarkers of environmental contamination in this study proved to be an extremely important tool for detecting the adverse effects of xenobiotics in the aquatic environment, even at low concentration.

Endosulfano, um pesticida organoclorado, tem sido banido pela maioria dos países desenvolvidos, embora seja ainda produzido e utilizado deliberadamente em países em desenvolvimento. Utilizado no controle de pragas, assim como no controle de insetos em Programas de Saúde Pública em alguns países, seus efeitos no meio ambiente e sua toxicidade continuam em discussão. Para alguns pesquisadores a bioacumulação nos organismos terrestres é considerada irrelevante, mas não para a vida aquática. O objetivo da presente pesquisa foi estudar os efeitos das concentrações subletais do endosulfano em peixes de água doce Cyprinus carpio, (Linnaeus, 1758). Os peixes foram expostos durante 15 dias, a uma concentração de 0,001mg/L de endosulfano utilizando o dimetilsulfóxido (DMSO) a 0,1% como solvente. A atividade da acetilcolinesterase do músculo axial e cerebral assim como a morfometria, histopatologia e a ultraestrutura do fígado desses peixes foram avaliadas. O índice somático hepático e o peso dos fígados mostraram valores menores quando comparados ao grupo controle, observando-se também, alterações histopatológicas e ultraestruturais. Nenhuma alteração significante na atividade da acetilcolinesterase muscular e cerebral foram observadas. Os resultados sugerem que o organoclorado endosulfano causou efeitos tóxicos no metabolismo hepático dos peixes expostos a doses subletais.

Respostas biológicas à presença de poluentes, também chamadas biomarcadores, podem ser usadas como indicadores precoces de contaminação ambiental. Esses biomarcadores são usados em programas de monitoramento ambiental, porém, devido às características de cada espécie animal usada como bioindicadora, a utilização de biomarcadores deve ser precedida da padronização dos métodos. A atividade da acetilcolinesterase é um dos mais antigos biomarcadores de contaminação aquática em peixes. Pesticidas organofosforados e carbamatos atuam como inibidores da acetilcolinesterase, outros compostos, porém, parecem também ter esta capacidade. É motivo de controvérsia na literatura a atividade anticolinesterásica do organoclorado endosulfano. Neste trabalho foi escolhida uma espécie nativa de peixe (Ancistrus multispinnis) e a viabilidade do uso da atividade acetilcolinesterásica como biomarcador de contaminação por endosulfano foi avaliada. Uma dose subletal de endosulfano (4 mg/kg) intracelomática foi administrada e uma amostra de músculo retirada após 24, 48 e 96 horas. A atividade acetilcolinesterásica foi medida e não se encontrou diferença estatística significativa em comparação ao grupo controle. Uma correlação negativa foi encontrada entre o peso e comprimento dos peixes em relação à atividade da enzima. Não houve correlação da atividade enzimática com o sexo dos animais. Esta informação se torna relevante em programas de monitoramento ambiental, onde se compara a atividade colinesterásica de peixes coletados em diferentes locais. O estudo dos efeitos do endosulfano em laboratório é importante no sentido de elucidar possíveis mecanismos de ação, viabilidade do uso do biomarcador e contribuir para a interpretação de resultados obtidos em pesquisas de campo.