The combination of urbanization and global warming leads to urban overheating and compounds the frequency and intensity of extreme heat events due to climate change. Yet, the risk of urban overheating can be mitigated by urban green-blue-grey infrastructure (GBGI), such as parks, wetlands, and engineered greening, which have the potential to effectively reduce summer air temperatures. Despite many reviews, the evidence bases on quantified GBGI cooling benefits remains partial and the practical recommendations for implementation are unclear. This systematic literature review synthesizes the evidence base for heat mitigation and related co-benefits, identifies knowledge gaps, and proposes recommendations for their implementation to maximize their benefits. After screening 27,486 papers, 202 were reviewed, based on 51 GBGI types categorized under 10 main divisions. Certain GBGI (green walls, parks, street trees) have been well researched for their urban cooling capabilities. However, several other GBGI have received negligible (zoological garden, golf course, estuary) or minimal (private garden, allotment) attention. The most efficient air cooling was observed in botanical gardens (5.0 ± 3.5°C), wetlands (4.9 ± 3.2°C), green walls (4.1 ± 4.2°C), street trees (3.8 ± 3.1°C), and vegetated balconies (3.8 ± 2.7°C). Under changing climate conditions (2070–2100) with consideration of RCP8.5, there is a shift in climate subtypes, either within the same climate zone (e.g., Dfa to Dfb and Cfb to Cfa) or across other climate zones (e.g., Dfb [continental warm-summer humid] to BSk [dry, cold semi-arid] and Cwa [temperate] to Am [tropical]). These shifts may result in lower efficiency for the current GBGI in the future. Given the importance of multiple services, it is crucial to balance their functionality, cooling performance, and other related co-benefits when planning for the future GBGI. This global GBGI heat mitigation inventory can assist policymakers and urban planners in prioritizing effective interventions to reduce the risk of urban overheating, filling research gaps, and promoting community resilience.

Based on country-specific panel data from 1990–2014 for 86 different countries, we quantify the effects of forests and agricultural land in CO₂ emissions, using the framework of the Environmental Kuznets Curve (EKC). The results from the dynamic panel data method reveal that forests are an important determinant in reducing CO₂ emissions globally, but the effects vary by region. All else constant, we estimate a 0.11% decline in CO₂ emissions per 1% increase in the forest area globally. However, the agricultural sector is found to be a true CO₂ emitter. Our study provides additional empirical evidence for the roles of forests in regulating atmospheric CO₂, further reinforcing the importance of forests in global climate change policies.

Despite its widespread recognition as a successful model of participatory forest management, the community forestry program in Nepal is often criticized for its protection-oriented emphasis. Recognizing the need for more active timber management, the government of Nepal recently adopted a scientific forest management (SFM) policy in the lowland tropical region. In this study, strength, weakness, opportunity, and threat analytical hierarchical process criteria were employed to understand stakeholder perceptions concerning SFM implementation in Nepal. The overall perception was prioritized in the order of strengths (35%), threats (28%), opportunities (22%), and weaknesses (16%). The study results suggest that there is agreement among stakeholders regarding the need for active management of forests in the tropical lowland region. However, the perceptions of academic researchers and non-government organization professionals differed from those of the other stakeholders in that those two groups were more concerned about potential corruption and uncertainties surrounding policy and legal issues. The findings suggest that the long-term success of SFM may depend on the ability of the government to develop a mechanism that is transparent and capable of ensuring equitable benefit sharing among stakeholders. While the stakeholder perception analysis performed in this study was focused on SFM implementation in Nepal, the results could have implications for other countries that practice the participatory model of forest governance as well.

While the Nepalese Community Forestry (CF) program is a highly prioritized development program with potential social, economic, and environmental benefits, its effect on the rural household economy has not been well examined. Using the cost–benefit analysis, this study examines the impact of the CF program on the household economy of forest users in the mid-hills region of Nepal. Both direct and indirect benefits and costs accrued by three wealth-ranked users were considered while calculating net present values. Results revealed that net benefits of the program were greater in rich households than in poor forest user households across a 50-year period. The poor households realized less direct and indirect benefits, yet they paid highest indirect costs incurred from the CF program. The CF program in Nepal requires prompt policy revisions to ensure cost-effective mechanisms to improve net income of poor households participating in the CF program.