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Keywords: toxin, nAChR, nAChR antagonist, APS12-2, chemotherapeutic agent
Published in DiRROS: 24.12.2024; Views: 77; Downloads: 22
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Keywords: queen caging, trapping comb, Varroa destructor, Deformed Wing Virus, Acute Bee Paralysis Virus
Published in DiRROS: 24.12.2024; Views: 83; Downloads: 15
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Abstract: This systematic review addresses the need for integrating social, ecological, and economic dimensions into sustainable forest management to enhance resilience and sustainability. Existing research reveals a gap in understanding community involvement and governance effectiveness. The review synthesizes findings from diverse studies, focusing on community forestry and agroforestry practices. An analysis of 48 peer-reviewed articles and case studies was conducted to identify the best practices and key themes. Results indicate that robust institutions and effective governance are essential for sustainable forest management. Community engagement and education significantly enhance sustainable practices, with fiscal subsidies in forestry proving more effective than agricultural subsidies. Agroforestry emerges as a strategy that boosts agricultural income and biodiversity through improved market access. The conclusions emphasize the need to address social inequalities and urban pressures while fostering community participation for effective forest management. Recommendations include strengthening institutional frameworks, promoting education for sustainable practices, developing targeted policies that address identified barriers, and leveraging community participation in decision-making processes.
Keywords: agroforestry systems, community forestry, institutional governance, sustainable forest management
Published in DiRROS: 24.12.2024; Views: 1455; Downloads: 33
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Abstract: Forests play a crucial role in global carbon cycling by absorbing and storing significant amounts of atmospheric carbon dioxide. Although boreal forests contribute to approximately 45% of the total forest carbon sink, tree growth and soil carbon sequestration are constrained by nutrient availability. Here, we examine if long-term nutrient input enhances tree productivity and whether this leads to carbon storage or whether stimulated microbial decomposition of organic matter limits soil carbon accumulation. Over six decades, nitrogen, phosphorus, and calcium were supplied to a Pinus sylvestris-dominated boreal forest. We found that nitrogen fertilization alone or together with calcium and/or phosphorus increased tree biomass production by 50% and soil carbon sequestration by 65% compared to unfertilized plots. However, the nonlinear relationship observed between tree productivity and soil carbon stock across treatments suggests microbial regulation. When phosphorus was co-applied with nitrogen, it acidified the soil, increased fungal biomass, altered microbial community composition, and enhanced biopolymer degradation capabilities. While no evidence of competition between ectomycorrhizal and saprotrophic fungi has been observed, key functional groups with the potential to reduce carbon stocks were identified. In contrast, when nitrogen was added without phosphorus, it increased soil carbon sequestration because microbial activity was likely limited by phosphorus availability. In conclusion, the addition of nitrogen to boreal forests may contribute to global warming mitigation, but this effect is context dependent.
Keywords: carbon storage, microbial communities, boreal forest, fertilization
Published in DiRROS: 23.12.2024; Views: 92; Downloads: 30
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Abstract: In cold climates, concrete structures confront durability challenges due to harsh conditions. This study evaluates the effects of incorporating natural fibers, such as hemp and flax fibers (at 1 vol%), and partially replacing cement with fly ash (at 25 and 50 wt%) on the properties of cementitious composites subjected to accelerated aging under freeze-thaw cycles and deicing salts. Findings reveal that natural fibers enhance the freeze-thaw resistance, reducing deterioration (scaling) to 5-8% after 56 cycles. When mortars were subjected to accelerated freeze-thaw cycles, the compressive strength of plain mortar significantly decreased (up to 57%). However, adding natural fibers to the matrix substantially reduced its compressive strength loss. In the case of flexural strength, plain mortars experienced 33% loss, while hemp, flax, and polypropylene fiber mortars showed only 13%, 23%, and 10% losses, respectively. Furthermore, mortars experience a notable enhancement in their energy absorption capacity when reinforced with natural fibers, particularly with hemp fibers (up to 348% higher than plain mortar). Under harsh conditions, hemp and flax-reinforced mortars, with 25wt% fly ash replacement, lose the compressive strength significantly however still demonstrate an alternative to synthetic fibers in terms of flexural strength. Even with 25wt% of fly ash, mortars with natural fiber reinforcement display significantly superior energy absorption capacities compared to plain mortars (up to 48%).
Keywords: cementitious composites, natural fibers, freeze-thaw cycles, mechanical properties, mass loss, fly ash
Published in DiRROS: 23.12.2024; Views: 86; Downloads: 27
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