Certification's limited contribution to sustainable aquaculture should complement public and private governance.

Rice is the most consumed staple food in the world and a key crop for food security. Much of the world's rice is produced and consumed in Asia where cropping intensity is often greater than 100% (more than one crop per year), yet this intensity is not sufficiently represented in many land use products. Agricultural practices and investments vary by season due to the different challenges faced, such as drought, salinity, or flooding, and the different requirements such as varietal choice, water source, inputs, and crop establishment methods. Thus, spatial and temporal information on the seasonal extent of rice is an important input to decision making related to increased agricultural productivity and the sustainable use of limited natural resources. The goal of this study was to demonstrate that hyper temporal moderate-resolution imaging spectroradiometer (MODIS) data can be used to map the spatial distribution of the seasonal rice crop extent and area. The study was conducted in Bangladesh where rice can be cropped once, twice, or three times a year.MODIS normalized difference vegetation index (NDVI) maximum value composite (MVC) data at 500 m resolution along with seasonal field-plot information from year 2010 were used to map rice crop extent and area for three seasons, boro (December/January-April), aus (April/May-June/July), and aman (July/ August-November/December), in Bangladesh. A subset of the field-plot information was used to assess the pixel-level accuracy of the MODIS-derived rice area. Seasonal district-level rice area statistics were used to assess the accuracy of the rice area estimates. When compared to field-plot data, the maps of rice versus non-rice exceeded 90% accuracy in all three seasons and the accuracy of the five rice classes varied from 78% to 90% across the three seasons. On average, the MODIS-derived rice area estimates were 6% higher than the sub-national statistics during boro, 7% higher during aus, and 3% higher during the aman season. The MODIS-derived sub-national areas explained (R 2 values) 96%, 93%, and 96% of the variability at the district level for boro, aus, and aman seasons, respectively.The results demonstrated that the methods we applied for analysing and interpreting moderate spatial and high temporal resolution imagery can accurately capture the seasonal variability in rice crop extent and area. We discuss the robustness of the approach and highlight issues that must be addressed before similar methods are used across other areas of Asia where a mix of rainfed, irrigated, or supplemental irrigation permits single, double, and triple cropping in a single calendar year.

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This paper introduces a special issue of Aquaculture that brings together the largest collection of research on aquaculture value chains compiled to date, comprising 19 individual papers and this introductory review. The introduction identifies five themes emerging from research on aquaculture value chains in the special issue, namely: multi-polarity, diversity and scale, dynamics of transformation, performance and equity, and technical and institutional innovation. Contrary to much research to date, the papers addressing these themes show how the expansion of aquaculture has resulted highly diverse configurations of production for consumption in the global South. Collectively, the papers highlight the need for greater attention to neglected value chain segments and categories of actor, modes of production, regulation, and innovation, and patterns of access to benefits. The papers synthesized also affirm the need for more rigorous and diverse future value chain research to illuminate the aquaculture sector's ongoing development, and contribute to the sustainable expansion as an increasingly important component of the global food system.

In the last few decades, disaster risk reduction programs and climate initiatives across the globe have focused largely on the intimate connections between vulnerability, recovery, adaptation, and coping mechanisms. Recent focus, however, is increasingly paid to community resilience. Community, placed at the intersection between the household and national levels of social organization, is crucial in addressing economic, social, or environmental disturbances disrupting human security. Resilience measures a community’s capability of bouncing back—restoring the original pre-disaster state, as well as bouncing forward—the capacity to cope with emerging post-disaster situations and changes. Both the ‘bouncing back’ and ‘moving forward’ properties of a community are shaped and reshaped by internal and external shocks such as climate threats, the community’s resilience dimensions, and the intensity of economic, social, and other community capitals. This article reviews (1) the concept of resilience in relation to climate change and vulnerability; and (2) emerging perspectives on community-level impacts of climate change, resilience dimensions, and community capitals. It argues that overall resilience of a place-based community is located at the intersection of the community’s resilience dimensions, community capitals, and the level of climate disruptions.

The recent coronavirus disease 2019 (COVID-19) pandemic is a global threat for healthcare management and the economic system, and effective treatments against the pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus responsible for this disease have not yet progressed beyond the developmental phases. As drug refinement and vaccine progression require enormously broad investments of time, alternative strategies are urgently needed. In this study, we examined phytochemicals extracted from Avicennia officinalis and evaluated their potential effects against the main protease of SARS-CoV-2. The antioxidant activities of A. officinalis leaf and fruit extracts at 150 µg/mL were 95.97% and 92.48%, respectively. Furthermore, both extracts displayed low cytotoxicity levels against Artemia salina. The gas chromatography–mass spectroscopy analysis confirmed the identifies of 75 phytochemicals from both extracts, and four potent compounds, triacontane, hexacosane, methyl linoleate, and methyl palminoleate, had binding free energy values of −6.75, −6.7, −6.3, and −6.3 Kcal/mol, respectively, in complexes with the SARS-CoV-2 main protease. The active residues Cys145, Met165, Glu166, Gln189, and Arg188 in the main protease formed non-bonded interactions with the screened compounds. The root-mean-square difference (RMSD), root-mean-square fluctuations (RMSF), radius of gyration (Rg), solvent-accessible surface area (SASA), and hydrogen bond data from a molecular dynamics simulation study confirmed the docked complexes′ binding rigidity in the atomistic simulated environment. However, this study′s findings require in vitro and in vivo validation to ensure the possible inhibitory effects and pharmacological efficacy of the identified compounds.

Recurrent haze in Southeast Asian countries including Singapore is largely attributable to rampant forest fires in Indonesia due to, for example, extensive slash-and-burn (S & B) culture. Drawing on the "treadmill of production" and environmental governance approach, we examine causes and consequences of this culture. We found that, despite some perceived benefits, its environmental consequences include deforestation, soil erosion and degradation, global warming, threats to biodiversity, and trans-boundary haze pollution, while the societal consequences comprise regional tension, health risks, economic and productivity losses, as well as food insecurity. We propose sustainability through a plural coexistence framework of governance for targeting S & B that incorporates strategies of incentives, education and community resource management.

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