During October and November, IWMI prepared for COP28 in Dubai where our team presented research that influenced the water and climate policy agenda and contributed to the negotiation process. During this period, IWMI researchers published studies on a variety of subjects, including cascading hazards, virtual water trade flows and questions for the sustainable development of food systems. Continue below to read a selection of their research journal publications released in October and November 2023.
Increasing risk of cascading hazards in the central Himalayas
The central Himalayas are seeing a rise in cascading hazards, or secondary hazards, that are triggered by primary hazards. For example, primary hazards such as earthquakes and avalanches can cause landslide dam and debris flow, which multiplies risks for communities and ecosystems. In this commentary published in Natural Hazards, IWMI’s Santosh Nepal and colleagues describe the distinctive features of natural hazards in the central Himalayas, their cascading mechanisms and impacts. The authors propose that understanding the processes driving cascading hazards and accounting for their compound risks is critical to informing the development of a risk management strategy. An informed risk management strategy must be accompanied with an integrated modeling framework, early warning systems, and sustainable mitigation and adaptation plans.
Read more here.
Does bilateral trade in cereals within SADC reflect virtual trade in water between countries with different water endowments?
When it comes to trading cereal crops, do Southern Africa Development Community (SADC) states with abundant water resources export water-intensive crops to fellow member states that face heightened water security, following comparative advantage economic trade theory? Or do other factors influence cereal trade? In a study published by Water International, IWMI’s Greenwell Matchaya and colleagues examined whether cereal trade reflects relative water availabilities. Researchers analyzed the determinants of intra-regional bilateral trade of cereal crops such as maize, sorghum, wheat, rice, millet, barley and rye for twelve member states. Virtual water trade flows were calculated using the specific water demand for each cereal yield. The study found that six out of twelve countries have a clear status as either a net exporter or net importer of cereals, and a single exporting and importing country dominates five of the seven cereals. Economic variables suggested a correlation between trade and production and consumption patterns, but not with water availability.
Read more here.
Water storages in Tana-Beles sub-basin of Ethiopia: What do we know, and where should we go?
Water storage in the Tana-Beles sub-basin of Ethiopia is a key resource for agriculture, drinking water, irrigation and energy, but few studies have assessed the range of water storage options available. For that reason, IWMI’s Meron Teferi Taye, Girma Yimer Ebrahim, Jonathan Lautze and Abdulkarim Hussein Seid worked with Tewodros T. Assefa to conduct a systematic literature review of peer-reviewed and grey publications written on surface and subsurface storage. Their assessment featured in SN Applied Sciences examined the key issues and connections in sub-basin storage. Researchers found that the literature focuses on natural storage rather than human-built storage options. Storage water quantity and quality are declining due to agricultural expansion, land degradation, sedimentation and increasing water withdrawals. They anticipate this gap will grow due to climate change, population and economic growth, which underscores the need for integrated nexus approaches to optimize water storage.
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Integrating open-source datasets to analyze the transboundary water–food–energy–climate nexus in Central Asia
The water-food-energy-climate nexus (WFEC Nexus) supports informed and transparent decision making according to trade-offs and synergies across sectors. IWMI’s Oyture Anarbekov and Zafar Gafurov sought to fill Central Asia’s WFEC Nexus data gap to benefit transboundary water management, which is challenged by data scarcity and unevenly distributed water resources across its five countries. Researchers obtained geodata through surveys, stakeholder consultations, and literature screening. The study, featured in Water, identified 60 unique data sets in six categories: climate, hydrology, geography and topography, geomorphology, ecology and anthropogenic uses. Researchers provided links to the sources of data and possible applications using the datasets to assist in WFEC Nexus data studies in Central Asia and beyond.
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Implications of changes in land use for ecosystem service values of two highly eroded watersheds in Lake Abaya Chamo sub-basin, Ethiopia
Land degradation contributes to the loss of ecosystems and the variety of services they provide to humans and the environment. IWMI’s Wolde Mekuria and co-researchers applied the value transfer valuation method to gauge changes in ecosystem service values in two degraded watersheds: the Aba-Bora and Guder in Ethiopia. The study, published in Ecosystem Services, found that over 41 years loss of cropland and grassland significantly affected ecosystem services—even when plantations and shrubland increased. The costs of the losses outweighed the gains; the Aba-Bora watershed lost $1.6 million in ecosystem service values and the Guder, $24.4 million. Reduction in crop and grazing lands increases vulnerability to shocks and threatens livelihoods for many smallholders. Sustainable management of catchments and gully rehabilitation measures downstream could help restore crop and grazing lands and their ecosystem service values.
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One hundred priority questions for the development of sustainable food systems in Sub-Saharan Africa
Sub-Saharan Africa is projected to double its population and triple its food demand over the next twenty-five years. This raises difficult questions concerning trade-offs between food production, social inequality and ecosystem health and how they can be balanced in policy and funding decision making. In this paper published by Land, IWMI’s Petra Schmitter, Maha Al-Zubi and colleagues identified 100 practical or research-focused questions that could help address trade-offs and have a positive impact on the resilience of food-production systems. Researchers collected 1339 questions from 331 experts and narrowed down their responses to 100 questions through online voting and participatory workshops. The final list was sectioned into 12 themes that grouped questions based on issues such as gender inequality and climate change. The study found that although differences in perspectives and priorities exist, respondents based across 55 countries largely raised consistent questions. The authors hope that this list will contribute to guiding research directions and priority funding decisions in Sub-Saharan Africa.
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Impact of soil surface temperature on changes in the groundwater level
Water evaporation from soil due to rising surface soil temperatures can lead to a decrease in groundwater levels. IWMI’s Zafar Gafurov and colleagues analyzed the impact of surface soil temperature on changes in groundwater levels in Uzbekistan’s Bukhara region. Focusing on data between 1991-2020, researchers used a linear regression analysis and analysis of variance tests to determine the relationship between soil surface temperature and groundwater level, and impact of the location of the measurements. The study concluded that both intercept and soil surface temperature significantly impact groundwater levels. Additionally, solar radiation and soil surface temperature have a strong relationship, with a correlation ratio of 0.840. Groundwater level and soil surface temperature have a moderately correlated relationship. Their results, published in Water 2023 led researchers to observe that soil surface temperature does indeed determine changes in the groundwater level in Uzbekistan’s Bukhara region.
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Factors affecting willingness to adopt climate insurance among smallholder farmers in Sri Lanka
Drought risk, exacerbated by climate change, exacts near annual damage to Sri Lanka’s agricultural sector, causing heavy losses for farmers and the national economy. Crop insurance schemes could shield farmers from agricultural risk, but farmers’ voluntary enrollment in highly subsidized crop insurance has remained low for the past several decades. In this study published by Climate Risk Management, IWMI’s Mohamed Aheeyar, Upali Amarasinghe, Giriraj Amarnath and Niranga Alahacoon investigated what influences farmers’ willingness to enroll in crop insurance. Their logistic regression model assessment of farmers who use irrigation and rainfed systems from North Central Province found that age, agriculture as the primary source of income, irrigation as the source of water and availability of a supplementary water source are significantly related to farmers’ willingness to pay for crop insurance. These results indicate that household socioeconomic factors and their contextualized risk perceptions shape decision making. This study can assist policymakers in formulating inclusive interventions for agriculture risk management and farmers’ resilience.
Read more here.
