New approaches to agricultural water use, and more:
A roundup of IWMI contributions to research articles and journals in February 2022
By Clara Colton Symmes, Princeton in Asia Fellow, IWMI
Researchers at the IWMI were collaborators on eight articles published in research journals in February 2022, covering a wide range of subject matter relating to how water use impacts security, health, agriculture, and more. Continue reading below to learn more about some of our latest research.
Water reuse to free up fresh water for higher-value use and increase climate resilience and water productivity
Because climate change’s impact on water availability affects all economic sectors and all aspects of daily life, integrated water resource management is key to strengthening climate resilience in communities and countries around the world. In an article published in Irrigation and Drainage, IWMI’s Pay Drechsel reflects on different efforts to adapt to water scarcity, focusing especially on wastewater reuse and compensating farmers with fresh water if they donate wastewater. Such processes, which incentivize the reuse of wastewater across sectors like industry and food production, expand the productivity of water in agriculture and beyond.
Read more here.
Predicting the chlorophyll content of maize over phenotyping as a proxy for crop health in smallholder farming systems
In South Africa, where smallholder farmers rely on productive crop yields to ensure livelihood security, IWMI’s Tafadzwanashe Mabhaudhi contributed to a study that tested the use of unmanned aerial vehicles (UAVs) in collecting data on maize crops. One of the most accurate ways to measure crop health is by assessing its chlorophyll content, due to its pigment and ability to indicate plant productivity. The study, published in Remote Sensing, found that UAVs — when used in combination with a robust machine algorithm — can serve as critical tools for shaping smallholder farmers’ water management decisions, given the technology’s accuracy.
Read more here.
Neglected and underutilised crops: A systematic review of their potential as food and herbal medicinal crops in South Africa
In South Africa, crops that were historically used for medicinal and nutritional purposes had eventually lost their status within farming systems, becoming underutilized over time. But an increased need to transition to more sustainable food systems has sparked renewed interest in these traditional crops. In a study published in Frontiers in Pharmacology, IWMI’s Tafadzwanashe Mabhaudhi worked with a team to examine 5,000 of these species, finding that several included pharmaceutical and nutritional properties. However, the research team emphasized that since current production levels remain low, a transdisciplinary approach to the industrial development of these crops is necessary to maximize these crops’ potential as food and medicine.
Read more here.
Sustainable surface water storage development: Measuring economic benefits and ecological and social impacts of reservoir system configurations
Dammed reservoirs can play an important role in adapting to seasonal shifts in water supply, but such infrastructure also often incurs detrimental social and environmental costs. In a paper published in Water, a team of researchers including IWMI’s Nishadi Eriyagama illustrated an approach to measuring how basin-wide water storage development affects the economic benefits and environmental and social impacts of water storage infrastructure. While small reservoir dams are typically considered as having a lower impact, basin-wide impact assessments reveal that the cumulative effects of many small reservoirs are comparable to basins with only a few large reservoirs.
Read more here.
Effects of long-term land use and land cover changes on ecosystem service values: An example from the Central Rift Valley, Ethiopia
IWMI’s Wolde Mekuria and Amare Haileslassie collaborated with a team to study how changes in land use and land cover are affecting ecosystem services. The study focuses on the Central Rift Valley lakes basin in Ethiopia, where the expansion of farmlands has negatively impacted grasslands, forestlands, and shrublands. Researchers estimated that over the last 47 years, the changes in land use and land cover resulted in a total loss of USD$62,110 × 106 worth of ecosystem services. The article, published in Land, identifies areas that are critical for conserving natural resources, reversing loss of ecosystem services, and achieving the Sustainable Development Goals related to water and food security.
Read more here.
Human arsenic exposure risk via crop consumption and global trade from groundwater-irrigated areas
Regardless of whether it originates from natural deposits or pollution, arsenic that finds its way into aquifers negatively impacts the health of populations who rely on groundwater for drinking. While these effects are widely studied, arsenic exposure through food intake is less well understood. In an article published in Environmental Research Letters, IWMI’s Mohammad Alam and Karen Villholth examine the threat of arsenic-polluted groundwater on irrigated crops. Unlike the health threats posed by arsenic-contaminated drinking water, the effects of arsenic-related crop contamination are not localized. Rather, due to global trade, countries with a dependency on imported crops — including many in the Middle East and small island nations — face potentially elevated health risks from food grown in arsenic hazard areas. Further, because of expanding trade and growing reliance on groundwater for crop production, the researchers call for additional studies to more deeply understand the health risks of arsenic exposure through food.
Read more here.
Heat units-based potential yield assessment for cotton production in Uzbekistan
In Uzbekistan, 40 percent of irrigated lands are used for growing cotton. However, in recent years, a lack of reliable water availability has combined with other factors to constrain cotton production to a point where yields are significantly lower than those in similar agro-climatic regions. IWMI’s Tulkin Yuldashev collaborated with a team of researchers to estimate the highest potential cotton yield given irrigation practices and air temperature. The resulting report, published in International Journal of Agricultural and Biological Engineering, concluded that lower elevations and latitudes are most suitable for cotton growing, and that the Uzbekistan government should focus on crop conversion in less suitable areas for cotton production.
Read more here.
Investigating effects of deficit irrigation levels and fertilizer rates on water use efficiency and productivity based on field observations and modeling approaches
In Pakistan, where nearly 19 percent of GDP is attributed to the agriculture sector, making the right decisions about proper irrigation practices and fertilizer management is key to not only feeding the country, but also sustaining agricultural livelihoods. While bread wheat is one of the most common crops grown, traditional farming practices are proving increasingly inefficient and unsustainable, especially in the face of intensifying drought conditions linked to climate change. In a study published in International Journal of Hydrology, IWMI’s Muhammad Shafeeque worked with researchers to examine how different irrigation and fertilizer treatments affected wheat growth over the course of two years. Researchers concluded that changing the type and timing of fertilizer and irrigation application would benefit wheat crop yields in Pakistan, and they predict that with further research, this method could be used in other climate regions as well.
Read more here.