Energy production and development have impacts on non-energy sector concerns including food security, water security, and sustainable land-use. Biofuel pathways differ in the tradeoffs they present within this “energy-water-food nexus” (EWFN). In this study, we focus on algal systems in the context of these interrelated challenges. We present areas of key consideration within the EWFN for large-scale algal system planning and commercialization, consider key resource inputs and outputs in the context of traditional biofuels compared with algal biofuels, provide examples of current global practices and EWFN impacts pertaining to liquid biofuels, and discuss potential opportunities and tradeoffs in applications of algal systems to EWFN challenges. The work described here could be used as a guide for future analysis that could quantitatively evaluate algal system feasibility in terms of economic viability, spatially and temporally explicit environmental impacts and production levels, and cross-sectorial impacts.

Land and water are vital resources for sustaining rural livelihoods and are critical for rural development as they form the basis of agriculture, the main economic activity for rural communities. Nevertheless, in most developing countries, land and water resources are unevenly distributed due to historical and socio-economic imbalances, hence the need for land reform policies to address these disparities. However, redistributing land without considering the interconnectedness of land and socio-ecological systems can compound existing food and water insecurity challenges. This study used a mixed research method, integrating both quantitative and qualitative data, to develop a framework to guide policy and decision-makers to formulate coherent strategies towards sustainable land redistribution programmes and achieve the desired outcomes. The approach was vital for integrating the broad and intricate interlinkages between water, land, and environmental resources. Therefore, the framework is based on transformative and circular models for informing strategic policy decisions towards sustainable land redistribution. The focus was on South Africa’s land redistribution plans and the implications on water and food security and rural development. The developed framework is designed to ensure the sustainability of agrarian reform and rural economic development. It is framed to address land and water accessibility inequalities, promote water and food security, and enhance rural development. A sustainable land redistribution increases the adaptive capacity of rural communities to climate change, enhances their resilience, and provides pathways towards Sustainable Development Goals (SDGs).

Regions affected by resource scarcity, poverty, and land-use conflicts need to advocate the merits of practices strongly grounded in sustainable land management. This review paper provides an analysis of agroforestry as an integrated system embedded in complex relations between resource uses in the Water–Energy–Land–Food (WELF) nexus. Using the African Sahel region as a case study, the paper explains the need for understanding land management practices, such as agroforestry, through the lens of trade-offs and benefits inherent in the WELF nexus. Agroforestry practices are demonstrated to be valuable interventions leading to i) resilience to climate stresses, ii) water, energy, and food securities, iii) mitigation of resource-oriented harbingers of conflicts and iv) development opportunities. These goals can also yield valuable results in terms of promoting sustainable development, i.e. functional ecosystems, livelihoods, and human security. Two overarching sub-nexuses, namely agroforestry–food–energy and agroforestry–food–water–climate, are identified in the Sahelian context and conceptualized. Primarily, the trade-offs outlined within these sub-nexuses are fuelwood vs. crops, use of land for more forests vs. more cropping, and water availability for agroforestry vs. agroforestry impacts on the water cycle. Despite the positive outcomes and opportunities, agroforestry systems in the Sahel still face some challenges such as vague land use rights, inadequate capacities and lack of investments. Policy recommendations are synthesized at three levels. This synthesis involves remedies to lessen pressures at the interlinks of WELF resource use, overarching remedies in the two sub-nexuses, and remedies across all the sectors and issues for improving agroforestry outcomes. Optimal remedies stress the importance of choosing the right land, water and plant combinations as well as incorporating efficiency measures and alternative sources. A successful agroforestry system is characterized by a conducive environment at the farm level in terms of institutions, management, enhancing the farmer's capacity, and good infrastructure.

Land and water are vital resources for sustaining rural livelihoods and are critical for rural development as they form the basis of agriculture, the main economic activity for rural communities. Nevertheless, in most developing countries, land and water resources are unevenly distributed due to historical and socio-economic imbalances, hence the need for land reform policies to address these disparities. However, redistributing land without considering the interconnectedness of land and socio-ecological systems can compound existing food and water insecurity challenges. This study used a mixed research method, integrating both quantitative and qualitative data, to develop a framework to guide policy and decision-makers to formulate coherent strategies towards sustainable land redistribution programmes and achieve the desired outcomes. The approach was vital for integrating the broad and intricate interlinkages between water, land, and environmental resources. Therefore, the framework is based on transformative and circular models for informing strategic policy decisions towards sustainable land redistribution. The focus was on South Africa’s land redistribution plans and the implications on water and food security and rural development. The developed framework is designed to ensure the sustainability of agrarian reform and rural economic development. It is framed to address land and water accessibility inequalities, promote water and food security, and enhance rural development. A sustainable land redistribution increases the adaptive capacity of rural communities to climate change, enhances their resilience, and provides pathways towards Sustainable Development Goals (SDGs).

Aside from the many services that soil provides, it also stores water and makes it available to crops, which is critical for food security. However, the necessity of further studies for overcoming the existing gap in relation to the role of soil in the water, energy, and food nexus system has been preoccupying the experts and specialists around the world for some time. In this sense, the balance between many key ecosystem components based on the Soil, water, energy, and food (SWEF) nexus framework is one of the key characteristics of holistic and accommodative watershed management systems. To the best of our knowledge, the watershed scale is used as a planning unit for the first time in the current study to construct a conceptual model for adaptive management of optimum land-use/cover allocation using SWEF. The method was then used for the Shazand Watershed, Iran. Numerous metrics, such as soil erosion, soil organic carbon (SOC), water and energy use, mass efficiency, and economic efficiency, were investigated. Finally, a compound indicator was used to generate the SWEF nexus index (SWEFNI) for various land-uses/crops for the node year 2014. SWFENI ranged from 0.19 (worst) for rangeland to 0.78 (best) for almond plantations, according to the findings. The study's present approach may be tested worldwide.