Absence of oxygen effect on microbial structure and methane production during drying and rewetting events

Natural environments with frequent drainage experience drying and rewetting events that impose fluctuations in water availability and oxygen exposure. These relatively dramatic cycles profoundly impact microbial activity in the environment and subsequent emissions of methane and carbon dioxide. In this study, we mimicked drying and rewetting events by submitting methanogenic communities from strictly anaerobic environments (anaerobic digestors) with different phylogenetic structures to consecutive desiccation events under aerobic (air) and anaerobic (nitrogen) conditions followed by rewetting. We showed that methane production quickly recovered after each rewetting, and surprisingly, no significant difference was observed between the effects of the aerobic or anaerobic desiccation events. There was a slight change in the microbial community structure and a decrease in methane production rates after consecutive drying and rewetting, which can be attributed to a depletion of the pool of available organic matter or the inhibition of the methanogenic communities. These observations indicate that in comparison to the drying and rewetting events or oxygen exposure, the initial phylogenetic structure and the organic matter quantity and quality exhibited a stronger influence on the methanogenic communities and overall microbial community responses. These results change the current paradigm of the sensitivity of strict anaerobic microorganisms to oxygen exposure

Social Participation in the Brazilian National Biodiversity Monitoring Program Leads to Multiple Socioenvironmental Outcomes

The Brazilian Biodiversity Monitoring Program (Monitora Program) is a long-term large-scale program aimed at monitoring the state of biodiversity and associated ecosystem services in the protected areas (PAs) managed by Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio). Encouraging qualified social participation is one of Monitora Program’s guiding principles. In this case study, we describe how citizen participation occurs in various stages of the Monitora Program, including planning, data collection, interpretation, and discussion of results. Aspects that are crucial for a legitimate and continuous involvement and participation are described. We also illustrate some of the results from the Program and discuss how the program can contribute to Brazil’s achievement of the United Nations (UN) Sustainable Development Goals (SDGs). In 2022, the program was implemented in 113 of the 334 protected areas managed by ICMBio, most of them in the Amazon. The program results are aligned to 12 of the 17 SDGs, influencing changes that move society closer to these goals at the local scale. Data from the Monitora Program can be used to support Brazilian SDG reporting, but this requires further developments. Social participation in Monitora Program has strengthened links between institutions and people of different profiles, enhancing participation in protected area (PA) management and generating multiple local impacts, while producing quality biodiversity information to inform decision-making in conservation

Variação temporal do microfitoplâncton no Canal Estuarino de Santos (SP)

An increase in abundance of potentially toxic dinoflagellates in Santos channel, located in a highly urbanized and eutrophized estuarine complex, was reported in literature. Prediction of such occurences is, essential, but phytoplankton community structure in dynamic estuarine systems are difficult to analyze. In the present work, we attempted to discuss microphytoplanktonic community in relation to physical variables to looking for shifts in composition in time scales of 24 hours and in pluviometric extremes. To achive our goal two surveys were performed on anchored stations of 25 hours (two complete tidal cicles) in Santos channel, during November 2005 (“dry season”) and April 2006 (“rainy season”). Diatoms community enhanced in periods of lower current velocity (tide peaks) during dry season, probably due to lower stratification after tidal runs and light availability, while dinoflagellates enhanced after rainfall events, probably due to a higher haline stratification and an increase in dissolved nutrients. The occurance of Pseudo-Nitzschia spp and Prorocentrum minimum blooms reinforces the necessity of a constatnt monitoring program in the region

Absence of oxygen effect on microbial structure and methane production during drying and rewetting events

Natural environments with frequent drainage experience drying and rewetting events that impose fluctuations in water availability and oxygen exposure. These relatively dramatic cycles profoundly impact microbial activity in the environment and subsequent emissions of methane and carbon dioxide. In this study, we mimicked drying and rewetting events by submitting methanogenic communities from strictly anaerobic environments (anaerobic digestors) with different phylogenetic structures to consecutive desiccation events under aerobic (air) and anaerobic (nitrogen) conditions followed by rewetting. We showed that methane production quickly recovered after each rewetting, and surprisingly, no significant difference was observed between the effects of the aerobic or anaerobic desiccation events. There was a slight change in the microbial community structure and a decrease in methane production rates after consecutive drying and rewetting, which can be attributed to a depletion of the pool of available organic matter or the inhibition of the methanogenic communities. These observations indicate that in comparison to the drying and rewetting events or oxygen exposure, the initial phylogenetic structure and the organic matter quantity and quality exhibited a stronger influence on the methanogenic communities and overall microbial community responses. These results change the current paradigm of the sensitivity of strict anaerobic microorganisms to oxygen exposure.Funding Agencies|Swedish Energy Agency [35624-2]</p

Biogas Potential for Improved Sustainability in Guangzhou, China—A Study Focusing on Food Waste on Xiaoguwei Island

As a result of rapid development in China and the growth of megacities, large amounts of organic wastes are generated within relatively small areas. Part of these wastes can be used to produce biogas, not only to reduce waste-related problems, but also to provide renewable energy, recycle nutrients, and lower greenhouse gases and air polluting emissions. This article is focused on the conditions for biogas solutions in Guangzhou. It is based on a transdisciplinary project that integrates several approaches, for example, literature studies and lab analysis of food waste to estimate the food waste potential, interviews to learn about the socio-technical context and conditions, and life-cycle assessment to investigate the performance of different waste management scenarios involving biogas production. Xiaoguwei Island, with a population of about 250,000 people, was chosen as the area of study. The results show that there are significant food waste potentials on the island, and that all studied scenarios could contribute to a net reduction of greenhouse gas emissions. Several socio-technical barriers were identified, but it is expected that the forthcoming regulatory changes help to overcome some of them