Southeast Asia

The countries around the world are dealing with air quality issues for decades due to their mode of production and energy usages. The outbreak of COVID-19 as a pandemic and consequent global economic shutdown, for the first time, provided a base for the real-time experiment of the effect of reduced emissions across the globe in abetting the air pollution issue. The present study dealt with the changes in Aerosol Optical Depth (AOD), a marker of air pollution, because of global economic shutdown due to the coronavirus pandemic. The study considered the countries in south and south-east Asia (SSEA), Europe and the USA for their extended period of lockdown due to coronavirus pandemic. Daily Aerosol Optical Depth (AOD) from Moderate-resolution imaging spectroradiometer (MODIS) and tropospheric column density of NO2 and SO2 from Ozone monitoring instrument (OMI) sensors, including meteorological data such as wind speed (WS) and relative humidity (RH) were analyzed during the pre-lockdown (2017–2019) and lockdown periods (2020). The average AOD, NO2 and SO2 during the lockdown period were statistically compared with their pre-lockdown average using Wilcoxon-signed-paired-rank test. The accuracy of the MODIS-derived AOD, including the changing pattern of AOD due to lockdown was estimated using AERONET data. The weekly anomaly of AOD, NO2 and SO2 was used for analyzing the space-time variation of aerosol load as restrictions were imposed by the concerned countries at the different points of time. Additionally, a random forest-based regression (RF) model was used to examine the effects of meteorological and emission parameters on the spatial variation of AOD. A significant reduction of AOD (- 20%) was obtained for majority of the areas in SSEA, Europe and USA during the lockdown period. Yet, the clusters of increased AOD (30–60%) was obtained in the south-east part of SSEA, the western part of Europe and US regions. NO2 reductions were measured up to 20–40%, while SO2 emission increased up to 30% for a majority of areas in these regions. A notable space-time variation was observed in weekly anomaly. We found the evidence of the formation of new particles for causing high AOD under high RH and low WS, aided by the downward vertical wind flow. The RF model showed a distinguishable relative importance of emission and meteorological factors among these regions to account for the spatial variability of AOD. Our findings suggest that the continued lockdown might provide a temporary solution to air pollution; however, to combat persistent air quality issues, it needs switching over to the cleaner mode of production and energy. The findings of this study, thus, advocated for alternative energy policy at the global scale.

This paper develops a conceptual framework with an indicator-based approach to assess Climate-Smart Villages (CSVs) and applies it to case study sites in Lao PDR (Ekxang CSV), Cambodia (Rohal Suong CSV), and Vietnam (Tra Hat CSV) in Southeast Asia. The intensification, extensification, diversification, commercialization, alteration of practices, use of common lands, migration strategies that can augment climate resilience, farm income, assets, and food security are assessed based on a composite index of the strategies and key outcome variables. The study demonstrates a method that can be applied widely for assessing climate-smart agriculture strategies and finding possible entry points for climate-smart interventions. The influence of gender in resource control and livelihood strategies is also discussed. It is also evident that the climate-smart interventions can augment different livelihood strategies of farmers and enhance the developmental and climate resilience outcomes. There is a need to prioritize the possible interventions in each case and implement them with the help of donor agencies, local institutions, and government offices.

After introducing the objectives and outcomes of Humidtropics, and some institutional constraints the research program faced, this chapter offers a synthesis of achievements, gaps and challenges of agricultural research for development activities implemented in the Humidtropics Central Mekong Action Area, as well as a discussion of the challenges faced. This chapter provides lessons learned from implementing agricultural research for development in this region, and offers insights and recommendations that could support integrated agricultural systems research in the Mekong region and elsewhere.

After reviewing the main causes and effects of land degradation and erosion in the uplands of mainland Southeast Asia, this chapter presents several case studies of recent land-use changes governed by economic, political and institutional transitions, the expansion of teak and rubber tree plantations in northern Laos and southwest China, respectively, and of monocropping coffee in the Central Highlands of Viet Nam. We explain how these environmental disturbances are altering water and soil resources across different geographic scales, from the agricultural plot to the headwater catchment. Examples of coping strategies combining field trials and participatory approaches are illustrated with several case studies taken from research for development activities conducted in Cambodia, Laos, Viet Nam and the Yunnan Province of China. These activities were part of the CGIAR Research Program on Integrated Systems for the Humid Tropics (Humidtropics) in the Central Mekong Action Area. We propose solutions for sustainable agricultural intensification to diversify income, improve dietary diversity and improve natural resource management. The accomplishment of these objectives requires longterm involvement with ethnic minority communities that have been the particular focus in the target areas. The three-anda-half-year lifespan of Humidtropics in the Mekong region was a short period. It would require extension to maintain the carefully built and nurtured relationships with local implementation partners and local farming communities, and reach its full promise.