联合国大学

Geopolitical conflicts are increasingly threatening global food security, economic stability, and peace, impacting Tanzania's tea agrifood system. This study develops a quantitative Resource Nexus-based system dynamics simulation model assessing the feedbacks and interdependencies among key environmental and socioeconomic resources shaping system vulnerability and resilience in the context of geopolitical tensions. Over a 10-year horizon (2024-2034), the model simulates interactions among land use, agricultural inputs, capital productivity, and export performance, as the main variables driving the tea agrifood system in the context of geopolitical tensions, and generates vulnerability and resilience indices. Results indicate that rising geopolitical tensions increase vulnerabilities in land use, inputs, and capital, reducing agricultural productivity and export potential that negatively impact income generation and decent livelihoods. The study recommends adaptive strategies (i.e., intensive agricultural mechanization, capacity building, and modern tea markets) and transformative change policies (i.e., conflict resolution, sustainable agriculture, and agrifood systems governance and policy reforms) can stabilize resource performance, lowering vulnerability and strengthening the sector's resilience, which is essentially shaped by multiple archetypes, such as limits to growth and shifting the burden archetypes. This study contributes to the growing knowledge on the consideration of Resource Nexus on achieving agrifood resilience and finally recommends policy renovations that facilitate sustainable livelihoods and conflict prevention.

Heavy metal pollution from mining activities and urban runoff poses a serious threat to public health and aquatic ecosystems in vulnerable communities around the Bolivia-Peru transboundary Lake Titicaca basin. This study evaluates the use of two abundant wetland plants-totora (Schoenoplectus californicus) and reed (Phragmites australis)-as low-cost, locally available biosorbents for the removal of dissolved iron (Fe2+) from the Pallina River, a major contaminant source to Cohana Bay. Monitoring data from Bolivia's Ministry of Environment and Water (2019-2022) revealed Fe2+ concentrations exceeding the national legal limit (0.3 mg/L) by more than 20 times during the dry season. Laboratory experiments using synthetic Fe2+ solutions (20 mg/L) optimized biosorption conditions, identifying pH 5, 4-6 g/L biomass, fine particle size (0.15-0.212 mm), and a 3 h contact time as optimal. Both plants followed pseudo-second-order kinetics and Langmuir isotherms. Totora showed superior performance, achieving a maximum capacity of 7.8 mg/g compared to reed's 2.9 mg/g. Continuous-flow column tests removed up to 95% of Fe2+ from synthetic water. When applied to real Pallina River water, totora achieved 50% Fe2+ removal despite reduced efficiency due to competing organic matter. The findings demonstrate the potential of totora-based biosorption as a scalable, nature-based solution for transboundary water management. The policy implications of this study are profound under the national and global water and wetland governance mechanisms and transboundary frameworks like the Binational Autonomous Authority of Lake Titicaca (ALT, est. 1996) and Ramsar Convention.

Global water scarcity has intensified competition among different water-use sectors. Collection, treatment, and fit-for-purpose use of wastewater generated by non-agricultural activities offers an opportunity in augmenting water supplies, recovering nutrients and energy, and mitigating pollution. Disparities across countries persist with high-income nations treating 91.5% of wastewater, whereas low-income countries managing to treat only a small fraction (5.8%). Major challenges include limited investments, lack of pertinent policies and application of regulations, and fragmented institutional support amid aging infrastructure, emerging contaminants, and limited resource recovery, particularly in developing regions. Implementation of advanced treatment technologies, regulatory frameworks, and integrated resource management are fundamental to address such challenges. Investments in wastewater monitoring, governance, and capacity-building are essential to achieving safely managed wastewater systems. Such efforts can transform wastewater into a sustainable water resource, support public health and environmental protection, and provide economic benefits. Learning from successful policies, such as the EU's Urban Wastewater Treatment Directive and the US Clean Water Act, can guide global efforts in line with the global sustainability agenda.

Sacred forests in urban areas, often regarded as green oases, are vital yet understudied components of city ecosystems, providing significant ecological benefits. This study investigates the role of sacred forests in conserving biodiversity, sequestering carbon, and mitigating local temperatures in Japanese cities. Through botanical records, biodiversity metrics, carbon estimates, and spatial analysis, we documented 170 species from 64 families, including four of conservation concern. These forests also demonstrated carbon storage and helped regulate urban microclimates, as evidenced by surface temperature differences that indicate their role in mitigating heat in densely populated urban areas. Despite their small size, sacred forests make disproportionately large contributions to urban resilience. By protecting species, enhancing climate regulation, and conserving cultural heritage, they support global sustainability goals, such as the Kunming–Montreal Global Biodiversity Framework and the Sustainable Development Goals. The results highlight the importance of including sacred forests in urban policy and planning as culturally resilient green infrastructure. Promoting their preservation through policy and community support is key to maximizing ecological benefits and creating more nature-friendly cities.

Environmental innovation is presented in the public debate as a tool to mitigate climate change, while promoting growth and employment. However, the empirical evidence on its socioeconomic impact is limited to specific types of innovation, sectors, and countries. In this paper, we investigate the direct and indirect effects of environmental product and process innovation in the context of global trade. To conduct our investigation, we build and empirically calibrate a model of the world economy on environmental accounts, socioeconomic accounts, and world input-output tables. We use it to simulate the effects of environmental product and process innovation in different sectors over the period 2020-2040. Our findings point to positive and significant effects in most sectors. However, they confirm the importance of substitution effects between more and less polluting products, imported and domestic. Furthermore, significant trade-offs emerge between promoting growth and supporting employment. These effects vary substantially depending on the type of innovation and sector. The main implication is that industrial policies to promote innovation should be calibrated to the specific policy goal and patterns of innovation prevailing in each sector.