Visions from Local Populations for Livelihood-Based Solutions to Promote Forest Conservation Sustainability in the Congo Basin

Forest management practices that aim to mitigate the threats of deforestation and forest degradation can inadvertently threaten the ability of forest-dependent local populations to meet basic daily sustenance needs. Stakeholder engagement can help find common ground between environmental goals and the livelihood needs of local populations. A starting point for local stakeholder engagement is to gather insights into how forest management differentially impacts the livelihoods and well-being of these populations, which may be quite heterogeneous in their perspectives and livelihood needs. Towards this end, we conducted semi-structured first-person interviews in forest-dependent communities in Cameroon about perspectives on and suggestions about forest resources and management. This study provides insights into commonalities and differences of perspectives within and among local populations and supports the use of stakeholder engagement strategies that facilitate bidirectional communication and take into consideration diverse perspectives and priorities.     

Liquid Exfoliated Co(OH)2 Nanosheets as Low‐Cost,Yet High‐Performance,Catalysts for the Oxygen Evolution Reaction

Identifying cheap, yet effective, oxygen evolution catalysts is critical to the advancement of water splitting. Using liquid exfoliated Co(OH)₂ nanosheets as a model system, a simple procedure is developed to maximize the activity of any oxygen evolution reaction nanocatalyst. First the nanosheet edges are confirmed as the active areas by analyzing the catalytic activity as a function of nanosheet size. This allows the authors to select the smallest nanosheets (length ≈50 nm) as the best performing catalysts. While the number of active sites per unit electrode area can be increased via the electrode thickness, this is found to be impossible beyond ≈10 µm due to mechanical instabilities. However, adding carbon nanotubes increases both toughness and conductivity significantly. These enhancements mean that composite electrodes consisting of small Co(OH)₂ nanosheets and 10 wt% nanotubes can be made into freestanding films with thickness of up to 120 µm with no apparent electrical limitations. The presence of diffusion limitations results in an optimum electrode thickness of 70 µm, yielding a current density of 50 mA cm^?2 at an overpotential of 235 mV, close to the state of the art in the field. Applying this procedure to a high‐performance catalyst such as NiFeO_x should significantly surpass the state of the art.     

Biodiversity improves the ecological design of sustainable biofuel systems

For algal biofuels to become a commercially viable and sustainable means of decreasing greenhouse gas emissions, growers are going to need to design feedstocks that achieve at least three characteristics simultaneously as follows: attain high yields; produce high quality biomass; and remain stable through time. These three qualities have proven difficult to achieve simultaneously under the ideal conditions of the laboratory, much less under field conditions (e.g., outdoor culture ponds) where feedstocks are exposed to highly variable conditions and the crop is vulnerable to invasive species, disease, and grazers. Here, we show that principles from ecology can be used to improve the design of feedstocks and to optimize their potential for “multifunctionality.” We performed a replicated experiment to test these predictions under outdoor conditions. Using 80 ponds of 1,100 L each, we tested the hypotheses that polycultures would outperform monocultures in terms of the following functions: biomass production, yield of biocrude from biomass, temporal stability, resisting population crashes, and resisting invasions by unwanted species. Overall, species richness improved stability, biocrude yield, and resistance to invasion. While this suggests that polycultures could outperform monocultures on average, invasion resistance was the only function where polycultures outperformed the best single species in the experiment. Due to tradeoffs among different functions that we measured, no species or polyculture was able to maximize all functions simultaneously. However, diversity did enhance the potential for multifunctionality—the most diverse polyculture performed more functions at higher levels than could any of the monocultures. These results are a key finding for ecological design of sustainable biofuel systems because they show that while a monoculture may be the optimal choice for maximizing short‐term biomass production, polycultures can offer a more stable crop of the desired species over longer periods of time.