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Tropical stream ecosystems are under increasing human pressure, making the development of effective restoration approaches and expanding knowledge in this field urgent. This study evaluated the impact of riparian vegetation restoration and environmental context on stream ecosystem functioning by measuring key ecosystem functions - gross primary production (GPP), ecosystem respiration (ER), and nutrient uptake of ammonium and soluble reactive phosphorus - across ten tropical streams in southeastern Brazil. The streams represented a gradient from clearcut areas (impacted reaches) to relatively pristine conditions (reference reaches), including intermediate stages of vegetation recovery (restored reaches). In the short-term (~15-20 years after restoration), restoration led to reduced GPP akin to reference reaches. Yet, ER did not show the anticipated increase, suggesting a longer timeframe is necessary for restored streams to emulate the functional characteristics of reference reaches. Additionally, the restored reaches did not achieve the nutrient uptake efficiencies observed in both impacted and reference reaches, pointing to a partial recovery of ecosystem function. This study suggests that while riparian vegetation restoration contributes positively to certain aspects of stream function, environmental variables less related to this type of restoration, such as discharge and hydromorphology, significantly influence stream ecosystem functioning, highlighting the importance of considering environmental context in restoration efforts. A more holistic approach, possibly encompassing broader hydromorphological and habitat enhancements, is needed to fully restore ecological processes in these vital ecosystems. These insights are critical for informing future tropical stream restoration projects, advocating the use of ecosystem function metrics as comprehensive indicators of ecological recovery and restoration success.

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Ciprofloxacin (CIP) is an antimicrobial "pseudo-persistent" in aquatic ecosystems. Once dispersed in the water compartments, it can also affect the microalgae. Thus, the evaluation of its long-term ecotoxicological effects is necessary. CIP interactions with other pharmaceuticals are not well known. In this study, we investigated the toxic effects of CIP alone and combined with caffeine (CAF), using the modified Gompertz model parameters and the chlorophyll-a production of the microalga Raphidocelis subcapitata as endpoints, throughout a 16-day exposure assay. The exposure to CIP alone led to significant reductions of the growth rate and the cell density of the microalgae compared to control groups. The combination with CAF lowered the adverse effects of CIP to R. subcapitata. However, as the toxicity is dynamic, our results indicated that the toxic effects in respect to the studied endpoints changed throughout the exposure period, reinforcing the need for longer-term ecotoxicity assessments.

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The potential impacts of citizen science initiatives are increasing across the globe, albeit in an imbalanced manner. In general, there is a strong element of trial and error in most projects, and the comparison of best practices and project structure between different initiatives remains difficult. In Brazil, the participation of volunteers in environmental research is limited. Identifying the factors related to citizen science projects' success and longevity within a global perspective can contribute for consolidating such practices in the country. In this study, we explore past and present projects, including a case study in Brazil, to identify the spatial and temporal trends of citizen science programs as well as their best practices and challenges. We performed a bibliographic search using Google Scholar and considered results from 2005-2014. Although these results are subjective due to the Google Scholar's algorithm and ranking criteria, we highlighted factors to compare projects across geographical and disciplinary areas and identified key matches between project proponents and participants, project goals and local priorities, participant profiles and engagement, scientific methods and funding. This approach is a useful starting point for future citizen science projects, allowing for a systematic analysis of potential inconsistencies and shortcomings in this emerging field.

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ABSTRACT The potential impacts of citizen science initiatives are increasing across the globe, albeit in an imbalanced manner. In general, there is a strong element of trial and error in most projects, and the comparison of best practices and project structure between different initiatives remains difficult. In Brazil, the participation of volunteers in environmental research is limited. Identifying the factors related to citizen science projects' success and longevity within a global perspective can contribute for consolidating such practices in the country. In this study, we explore past and present projects, including a case study in Brazil, to identify the spatial and temporal trends of citizen science programs as well as their best practices and challenges. We performed a bibliographic search using Google Scholar and considered results from 2005-2014. Although these results are subjective due to the Google Scholar's algorithm and ranking criteria, we highlighted factors to compare projects across geographical and disciplinary areas and identified key matches between project proponents and participants, project goals and local priorities, participant profiles and engagement, scientific methods and funding. This approach is a useful starting point for future citizen science projects, allowing for a systematic analysis of potential inconsistencies and shortcomings in this emerging field.

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The management of urban water resources plays an important role for developing countries. The Tietê and Pinheiros Rivers (São Paulo, Brazil) are affected by domestic and industrial effluents and by the diffuse pollution. This research aimed to quantify 134 variables in the water of Tietê and Pinheiros Rivers (approximately 7,200 and 6,600 analyses, respectively) from August 2007 to December 2008. The idea was to verify if the fact that both rivers are located in the same basin is enough to consider the application of a single management plan for both. Data showed that the rivers presented significant anthropogenic interference. The results suggested that such rivers must be subjected to individual management plans since there were exclusive occurrences (variables that were only detected in one of the rivers). Moreover, there was a statistically significant difference between rainy and dry periods for eleven variables (p*<0.05, ANOVA), reinforcing the special importance of the temporal component within the monitoring program. It is expected that this study subsidize environmental recovery programs in the Tietê River, to which is recommendable to focus on prosecution of illegal wastewater releases, and in the Pinheiros River, to which special attention is suggested to the pollution derived from the pesticides load to the water body.

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The management of urban water resources plays an important role for developing countries. The Tietê and Pinheiros Rivers (São Paulo, Brazil) are affected by domestic and industrial effluents and by the diffuse pollution. This research aimed to quantify 134 variables in the water of Tietê and Pinheiros Rivers (approximately 7,200 and 6,600 analyses, respectively) from August 2007 to December 2008. The idea was to verify if the fact that both rivers are located in the same basin is enough to consider the application of a single management plan for both. Data showed that the rivers presented significant anthropogenic interference. The results suggested that such rivers must be subjected to individual management plans since there were exclusive occurrences (variables that were only detected in one of the rivers). Moreover, there was a statistically significant difference between rainy and dry periods for eleven variables (p*<0.05, ANOVA), reinforcing the special importance of the temporal component within the monitoring program. It is expected that this study subsidize environmental recovery programs in the Tietê River, to which is recommendable to focus on prosecution of illegal wastewater releases, and in the Pinheiros River, to which special attention is suggested to the pollution derived from the pesticides load to the water body.

O gerenciamento dos recursos hídricos urbanos desempenha um papel importante para os países em desenvolvimento. Os rios Tietê e Pinheiros (São Paulo, Brasil) são afetados por efluentes domésticos e industriais e pela poluição difusa. Esta pesquisa teve como objetivo quantificar 134 variáveis da água dos rios Tietê e Pinheiros (aproximadamente 7.200 e 6.600 análises, respectivamente) de Agosto de 2007 a Dezembro de 2008. A ideia foi verificar se o fato de os dois rios se localizarem na mesma bacia hidrográfica é suficiente para que se considere a aplicação de um único plano de manejo para ambos. Os dados mostraram que os rios apresentam significativa interferência antrópica. Os resultados sugeriram que tais rios devem ser submetidos a planos individuais de gerenciamento, uma vez que houve ocorrências exclusivas (variáveis que foram detectadas em apenas um dos rios). Além disso, houve diferença estatisticamente significativa entre os períodos seco e chuvoso para onze variáveis (p*<0,05, ANOVA), o que reforça a especial importância da componente temporal do programa de monitoramento. Espera-se que esse estudo ofereça subsídios para programas de recuperação ambiental do rio Tietê, para o qual é recomendado foco na repressão de lançamentos clandestinos de águas residuárias, e do rio Pinheiros, para o qual se sugere especial atenção à poluição derivada do aporte de pesticidas ao corpo de água.

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Determining reference concentrations in rivers and streams is an important tool for environmental management. Reference conditions for eutrophication-related water variables are unavailable for Brazilian freshwaters. We aimed to establish reference baselines for São Paulo State tropical rivers and streams for total phosphorus (TP) and nitrogen (TN), nitrogen-ammonia (NH(4) (+)) and Biochemical Oxygen Demand (BOD) through the best professional judgment and the trisection methods. Data from 319 sites monitored by the São Paulo State Environmental Company (2005 to 2009) and from the 22 Water Resources Management Units in São Paulo State were assessed (N = 27,131). We verified that data from different management units dominated by similar land cover could be analyzed together (Analysis of Variance, P = 0.504). Cumulative frequency diagrams showed that industrialized management units were characterized by the worst water quality (e.g. average TP of 0.51 mg/L), followed by agricultural watersheds. TN and NH(4) (+) were associated with urban percentages and population density (Spearman Rank Correlation Test, P < 0.05). Best professional judgment and trisection (median of lower third of all sites) methods for determining reference concentrations showed agreement: 0.03 & 0.04 mg/L (TP), 0.31 & 0.34 mg/L (TN), 0.06 & 0.10 mg-N/L (NH(4) (+)) and 2 & 2 mg/L (BOD), respectively. Our reference concentrations were similar to TP and TN reference values proposed for temperate water bodies. These baselines can help with water management in São Paulo State, as well as providing some of the first such information for tropical ecosystems.

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