Appraisal of complementarity of subsurface drip fertigation and conservation agriculture for physiological performance and water economy of maize
The Indo-Gangetic Plains (IGP) in north-west (NW) India are facing a severe decline in ground water due to prevalent rice-based cropping systems. To combat this issue, conservation agriculture (CA) with an alternative crop/s, such as maize, is being promoted. Recently, surface drip fertigation has also been evaluated as a viable option to address low-nutrient use efficiency and water scarcity problems for cereals. While the individual benefits of CA and sub-surface drip (SSD) irrigation on water economy are well-established, information regarding their combined effect in cereal-based systems is lacking. Therefore, we conducted a two-year field experiment in maize, under an ongoing CA-based maize-wheat system, to evaluate the complementarity of CA with SSD irrigation through two technological interventions–– CA+ (residue retained CA + SSD), PCA+ (partial CA without residue + SSD) – at different N rates (0, 120 and 150 kg N ha-1) in comparison to traditional furrow irrigated (FI) CA and conventional tillage (CT) at 120 kg N ha-1. Our results showed that CA+ had the highest grain yield (8.2 t ha-1), followed by PCA+ (8.1 t ha-1). The grain yield under CA+ at 150 kg N ha-1 was 27% and 30% higher than CA and CT, respectively. Even at the same N level (120 kg N ha-1), CA+ outperformed CA and CT by 16% and 18%, respectively. The physiological performance of maize also revealed that CA+ based plots with 120 kg N ha-1 had 12% and 3% higher photosynthesis rate at knee-high and silking, respectively compared to FI-CA and CT. Overall, compared to the FI-CA and CT, SSD-based CA+ and PCA+ saved 54% irrigation water and increased water productivity (WP) by more than twice. Similarly, a greater number of split N application through fertigation in PCA+ and CA+ increased agronomic nitrogen use efficiency (NUE) and recover efficiency by 8–19% and 14–25%, respectively. Net returns from PCA+ and CA+ at 150 kg N ha-1 were significantly higher by US$ 491 and 456, respectively than the FI-CA and CT treatments. Therefore, CA coupled with SSD provided tangible benefits in terms of yield, irrigation water saving, WP, NUE and profitability. Efforts should be directed towards increasing farmers’ awareness of the benefits of such promising technology for the cultivating food grains and commercial crops such as maize. Concurrently, government support and strict policies are required to enhance the system adaptability.
Technology / Economic analysis / Crop yield / Leaf area index / Residues / Tillage / Water-use efficiency / Irrigation methods / Irrigation water / Irrigation management / Photosynthesis / Maize / Water productivity / Nitrogen-use efficiency / Drip irrigation / Drip fertigation / Subsurface irrigation / Conservation agriculture
A spatio-temporal dataset on food flows for four West African cities
Gaining insight into the food sourcing practices of cities is important to understand their resilience to climate change, economic crisis, as well as pandemics affecting food supply and security. To fill existing knowledge gaps in this area food flow data were collected in four West African cities - Bamako (Mali), Bamenda (Cameroon), Ouagadougou (Burkina Faso), and Tamale (Ghana). The data cover, depending on the city, road, rail, boat, and air traffic. Surveys were conducted for one week on average during the peak harvest, lean, and rainy seasons, resulting in a dataset of over 100,000 entries for 46 unprocessed food commodities. The data collected includes information on the key types of transportation used, quantity, source, and destination of the food flows. The data were used to delineate urban foodsheds and to identify city-specific factors constraining rural-urban linkages. The data can also be employed to inform academic and policy discussions on urban food system sustainability, to validate other datasets, and to plan humanitarian aid and food security interventions.
Modes of transport / Virtual water / Food products / Food security / Datasets / Cities / Markets / Commodities / Food systems / Rural-urban food supply chains
Determining the marketing margin for irrigation technologies in Ethiopia: a supply chain analysis. Adaptive Innovation Scaling - Pathways from Small-scale Irrigation to Sustainable Development
Households / Policies / Private sector / Non-governmental organizations / Government agencies / Multi-stakeholder processes / Climate variability / Drought / Agricultural productivity / Investment / Willingness to pay / Imports / Taxes / Costs / Credit / Financing / Market demand / Pumps / Solar powered irrigation systems / Farmer-led irrigation / Smallholders / Sustainable development / Innovation scaling / Supply chains / Marketing margins / Technology / Small-scale irrigation
Enhancing gender and youth inclusion in Ghana’s irrigated vegetable value chain. Adaptive Innovation Scaling - Pathways from Small-scale Irrigation to Sustainable Development
Financing / Project design / Agricultural development / Water user associations / Integrated water resources management / Collaboration / Learning / Intervention / Strategies / Regulations / Policies / Governmental organizations / Non-governmental organizations / Institutions / Multi-stakeholder processes / Employment / Women farmers / Farmer-led irrigation / Smallholders / Sustainable development / Small-scale irrigation / Innovation scaling / Agricultural value chains / Vegetable growing / Irrigated farming / Inclusion / Youth / Gender
Urban agriculture during economic crisis: lessons from Cuba, Sri Lanka and Ukraine. Policy brief
Economic crises take different forms and occur for various reasons, such as political conflicts and pandemics. What all these crises have in common is that they cause disruption to rural-urban food supply chains, resulting in food shortages for the urban poor, with the most direct impact being an increase in food prices. It is within this challenging context that we present empirical examples of the role of urban agriculture.
Pandemics / War / Conflicts / Resilience / Food security / Rural-urban food supply chains / Cities / Economic crises / Urban agriculture
Estimating the potential of spices for mineral provision in a refugee context in East Africa
Micronutrient deficiency remains an enormous problem in refugee settings. Transforming refugees’ food systems through the scaling up of kitchen gardening and fortifying relief food crops with minor food components including nutrient-dense spices can help improve the quality of staple foods. Globally, spices are indispensable in the daily diet and play an important role in the socio-cultural setting of different communities. Forty turmeric and curry powder samples were collected from different market establishments and geographic locations in East Africa. The samples were analyzed for selected elements using Portable X-Ray Fluorescence (PXRF). The contents of potassium (K), calcium (Ca), zinc (Zn) and strontium (Sr) in turmeric powder were statistically different among geographic origins (Ethiopia, Kenya and Uganda). We also aimed to determine if a small portion of spices (turmeric (5 g) and curry (4 g)) would contribute to an adequate intake (AI) or recommended dietary allowance (RDA) for selected minerals, for refugee men and women aged between 19 and 50 years as defined by the Food and Nutrition Board of the Institute of Medicine (IOM). For the reference groups, the contributions of turmeric and curry powder to AI/RDA for K, Ca and Zn varied between 0.48 to 4.13%. On the other hand, turmeric was identified to contribute gt; 20% AI/RDA for refugee men and women aged between 19 and 50 years for two micro minerals: manganese (Mn) and iron (Fe). Considering turmeric and curry powder of East African origins are good sources of minerals and present acceptable toxic metal(loid)s loads coupled with low cost, these spices particularly turmeric should be more widely popularized and recommended for food-to-spice fortification among the refugee population located in East Africa.
Turmeric / Minerals / Spices / Nutrition / Recommended dietary allowances / Refugees
Digital ethnography? Our experiences in the use of SenseMaker for understanding gendered climate vulnerabilities amongst marginalized agrarian communities
Digital innovations and interventions can potentially revolutionize agri-food systems, especially in coping with climate challenges. On a similar note, digital research tools and methods are increasingly popular for the efficient collection and analysis of real-time, large-scale data. It is claimed that these methods can also minimize subjective biases that are prevalent in traditional qualitative research. However, given the digital divide, especially affecting women and marginalized communities, these innovations could potentially introduce further disparities. To assess these contradictions, we piloted SenseMaker, a digital ethnography tool designed to capture individual, embodied experiences, biases, and perceptions to map vulnerabilities and resilience to climate impacts in the Gaya District in Bihar. Our research shows that this digital tool allows for a systematic co-design of the research framework, allows for the collection of large volumes of data in a relatively short time, and a co-analysis of the research data by the researchers and the researched. This process allowed us to map and capture the complexities of intersectional inequalities in relation to climate change vulnerability. However, we also noted that the application of the tool is influenced by the prior exposure to technology (digital devices) of both the enumerators and researched groups and requires significant resources when implemented in contexts where there is a need to translate the data from local dialects and languages to more dominant languages (English). Most importantly, perceptions, positionalities, and biases of researchers can significantly impact the design of the tool’s signification framework, reiterating the fact that researcher bias persists regardless of technological innovations in research methodology.
Social aspects / Technology / Transdisciplinary research / Agriculture / Women / Gender / Marginalization / Communities / Vulnerability / Climate change / Ethnography
Are farmers’ climate change adaptation strategies understated? Evidence from two communities in northern Ethiopian highlands
Research and policy analyses of climate change adaptation in Africa are often centre to examine adjustments in agricultural operations. This mainly bases on a misconception that rural households merely depend on agriculture for their livelihoods. This research aimed at positioning livelihood (farm and non-farm activities) as the centre of climate adaptation strategies to better understand rural households’ adaptation strategic options and capacities, using two rural communities in the Northern highlands of Ethiopia. The result showed that rural households have broader options both in farm and non-farm strategies for combating adverse climate condition than previously reported. A strong and positive association are found between wealth indicators such as farm size (0.08) and productive assets (0.0917) with farm-level adaptation strategies such as short maturing crop and irrigation. Non-farm adaptation strategies (such as business activities and wage employment) are, mainly, influenced by household demographic characteristics such as age of the household head (0.01) and adult household size (0.09). This indicates that there is no specific adaptation strategy panacea for rural households. Rather, rural households use a mix of strategies to meet the particular agro-ecological settings (for farm-level adaptation strategies), and infrastructure and the location of the community, which enable to access market and other services (for non-farm adaptation strategies). Thus, national level climate policies and strategies need to be tailored to address the specific agro-ecology, and infrastructure of the local area and the socio-economic context of the households in the two communities. In this regard, the different levels of government and nongovernmental organizations should provide more adaptation measures on agricultural extension services, access to loans, roads, transport, market, knowledge and creation of wage employment and business opportunities in the vicinity of rural communities and its surrounding towns.
Migration / Socioeconomic aspects / Rainfall / Irrigation / Soil conservation / Rural communities / Households / Livelihoods / Strategies / Farmers / Climate change adaptation
Managing African commons in the context of Covid-19 challenges
COVID-19 / Communities / Customary tenure / Water tenure / Co-management / Forestry / Climate change / Gender / Commons
Journal Whole Issues / Newsletter
Managing African commons in the context of Covid-19 challenges
COVID-19 / Social aspects / Resilience / Communities / Financing / Governance / Political aspects / Infrastructure / Water sharing / Women / Institutions / Co-management / Agroforestry / Customary tenure / Water tenure / Climate change mitigation / Climate change adaptation / Gender / Commons
Occurrence and distribution of long-term variability in precipitation classes in the source region of the Yangtze River
Various precipitation-related studies have been conducted on the Yangtze River. However, the topography and atmospheric circulation regime of the Source Region of the Yangtze River (SRYZ) differ from other basin parts. Along with natural uniqueness, precipitation constitutes over 60% of the direct discharge in the SRYZ, which depicts the decisive role of precipitation and a necessary study on the verge of climate change. The study evaluates the event distribution of long-term variability in precipitation classes in the SRYZ. The precipitation was classified into three precipitation classes: light precipitation (0–5 mm, 5–10 mm), moderate precipitation (10–15 mm, 15–20 mm, 20–25 mm), and heavy precipitation (gt;25 mm). The year 1998 was detected as a changing year using the Pettitt test in the precipitation time series; therefore, the time series was divided into three scenarios: Scenario-R (1961–2016), the pre-change point (Scenario-I; 1961–1998), and the post-change point (Scenario-II; 1999–2016). Observed annual precipitation amounts in the SRYZ during Scenario-R and Scenario-I significantly increased by 13.63 mm/decade and 48.8 mm/decade, respectively. The same increasing trend was evident in seasonal periods. On a daily scale, light precipitation (0–5 mm) covered most of the days during the entire period, with rainy days accounting for 83.50%, 84.5%, and 81.30%. These rainy days received up to 40%, 41%, and 38% of the annual precipitation during Scenario-R, Scenario-I, and Scenario-II, respectively. Consequently, these key findings of the study will be helpful in basin-scale water resources management.
Vegetation / Dry spells / Hydrological factors / Time series analysis / Drought / Rainfall / Rivers / Trends / Precipitation / Climate change
Multilateral development banks investment behaviour in water and sanitation: findings and lessons from 60 years of investment projects in Africa and Asia
Multilateral development banks (MDBs) play a pivotal role in financing water and sanitation infrastructure projects and thus have a major impact on the development of basic services. Although information about the MDBs’ investments is publicly available, it is dispersed and not easily comparable. A comprehensive compilation of MDBs’ water and sanitation investments has long been lacking. To address this gap, we assess water and sanitation financing by the three MDBs most relevant to Africa and Asia between 1960 and 2020: the World Bank, the African Development Bank, and the Asian Development Bank. We compile a new dataset by drawing on 3,639 water and sanitation projects and assess territorial trends, technology choices, distribution of financial burdens, and reforms to institutional arrangements. We find that MDBs’ investments align with changing patterns of urbanization and increasingly finance sanitation infrastructures including non-sewered technologies. However, our results also suggest that institutional reforms have addressed utility efficiency through investment in equipment and skills rather than through increased commercialization and private sector participation. The leverage effect of MDB investment on private financing is negligible, whereas co-financing from local governments dominates.
Policies / Public-private partnerships / Institutional reform / Investment / Development banks / Multilateral organizations / Goal 6 Clean water and sanitation / Sustainable Development Goals / Water supply
Effects of land use land cover change on streamflow of Akaki Catchment, Addis Ababa, Ethiopia
Evaluation of the hydrological impact of urbanization-induced land use land cover (LULC) changes for medium to large catchments is still an important research topic due to the lack of evidence to conclude about how local changes translate to impacts across scales. This study aims to provide evidence on the effects of LULC change on the streamflow of the Akaki catchment that hosts Addis Ababa, the capital city of Ethiopia. Since the comparative performance of classification algorithms is poorly understood, we compared the performance of one parametric and five non-parametric machine learning methods for LULC mapping using Landsat imageries. To investigate the effect of LULC changes on streamflow, a semi-distributed HEC-HMS model was calibrated and validated using daily discharge data at multiple sites. Findings of this study showed that: (i) the accuracy of classification and regression tree (CART) was superior to the other classifiers, (ii) from 1990 to 2020, urban and forest cover increased at the expense of agricultural and bare land, (iii) the performance of the HEC-HMS model was acceptable at all stations during both the calibration and validation periods, and (iv) the mean annual and main rainy seasonal streamflow of the catchment experienced significant increases due to LULC change but the simulated streamflow changes highly varied with the type of LULC classifier. This study contributes to the limited evidence on how catchments, with rapidly developing cities are prone to hydrological regime changes that need to be recognized, understood and quantified, and incorporated into urban planning and development.
Models / Machine learning / Hydrological factors / Reservoirs / Rivers / Urbanization / Stream flow / Catchment areas / Land cover change / Land use change
Upscaling micro-irrigation in the Indian states of Odisha and Assam: recommendations based on field evidence
Awareness / Capacity development / Irrigation systems / Irrigation water / Farmers / Smallholders / Water productivity / Resilience / Microirrigation
Five decades of freshwater salinization in the Amu Darya River Basin
Study region: The Amu Darya River (ADR) basin in Central Asia. Study focus: To understand the spatiotemporal patterns and underlying driving mechanisms of river salinization in arid environments, this study gathered 50 years (1970–2019) of water chemistry data from 12 locations along the ADR. The variations in discharge and salinity were assessed by a linear regression model and violin plot. The salinity-discharge relationships were evaluated by a general hyperbolic model and Spearman’s rank correlation coefficient. Random forest models were also constructed to identify the predominant drivers of river water salinization. Finally, a conceptual model of river water salinization was constructed. New hydrological insights for the region: The water salinity (S) in the upper stream of the ADR was 541–635 mg/L. Salinity showed an increasing trend along the river course, reaching 751–1560 mg/L downstream. In the downstream, the river salinity before the 1990 s (751–1128 mg/L) was slightly lower than that after the 1990 s (983–1560 mg/L). Generally, water salinity was notably correlated with river discharge (Q) in upstream, exhibiting a relationship of S= 17,497Q- 0.62, p lt; 0.05, before the 1990 s. Interannual variation in river salinity is mainly controlled by secondary salinization, and intra-annual variation is controlled by river flow. From upstream to downstream, the controlling salinization process changes from primary salinization to secondary salinization. Specifically, secondary salinization has accelerated due to intensified agricultural activities in recent years.
Models / Seasonal variation / Spatial variations / Hydrology / Discharges / Agriculture / Climate change / Salinity / River basins / Salinization / Freshwater
Remote sensing grassland productivity attributes: a systematic review
A third of the land on the Earth is composed of grasslands, mainly used for forage. Much effort is being conducted to develop tools to estimate grassland productivity (GP) at different extents, concentrating on spatial and seasonal variability pertaining to climate change. GP is a reliable indicator of how well an ecosystem works because of its close connection to the ecological system equilibrium. The most commonly used proxies of GP in ecological studies are aboveground biomass (AGB), leaf area index (LAI), canopy storage capacity (CSC), and chlorophyll and nitrogen content. Grassland science gains much information from the capacity of remote sensing (RS) techniques to calculate GP proxies. An overview of the studies on RS-based GP prediction techniques and a discussion of current matters determining GP monitoring are critical for improving future GP prediction performance. A systematic review of articles published between 1970 and October 2021 (203 peer-reviewed articles from Web of Science, Scopus, and ScienceDirect databases) showed a trend in the choice of the sensors, and the approaches to use are largely dependent on the extent of monitoring and assessment. Notably, all the reviewed articles demonstrate the growing demand for high-resolution sensors, such as hyperspectral scanners and computationally efficient image-processing techniques for the high prediction accuracy of GP at various scales of application. Further research is required to attract the synthesis of optical and radar data, multi-sensor data, and the selection of appropriate techniques for GP prediction at different scales. Mastering and listing major uncertainties associated with different algorithms for the GP prediction and pledging to reduce these errors are critical.
Vegetation index / Nitrogen content / Chlorophylls / Canopy / Above ground biomass / Leaf area index / Ecosystem services / Techniques / Monitoring / Estimation / Remote sensing / Prediction / Productivity / Grasslands
Prospects for treated wastewater reuse in agriculture in low- and middle-income countries: systematic analysis and decision-making trees for diverse management approaches
The Middle East and North Africa (MENA) region is suffering from severe water scarcity. Decision-makers in MENA are tackling this challenge by tapping the potential of reusing treated wastewater in agriculture so that large volumes of freshwater sources can be released for priority domestic needs. This aligns with the global efforts to make wastewater reuse mainstream in developing countries by overcoming the technological, infrastructural, health, and socio-cultural barriers that are limiting the expansion of wastewater reuse in agriculture. In this regard, this paper analyses the management modalities of wastewater reuse practices in agriculture in MENA by studying two case studies from Egypt and Jordan. The result of this analysis is a proposed decision-tree tool to help decision-makers in making optimal wastewater reuse decisions based on contextual factors including agricultural field demands, location, freshwater resources, sanitation coverage, and infrastructure, as well as regulations, policies, and restrictions for wastewater reuse. The decision-tree framework was operationalized and validated using the two case studies. The decision tree proved to be an effective framework in assisting decision-makers in making the optimum choice for wastewater reuse in agriculture. It aided the decision maker in evaluating potential reuse options and selecting between several courses of action.
Case studies / Institutions / Stakeholders / Wastewater treatment / Irrigation water / Agriculture / Wastewater irrigation / Decision making / Wastewater management / Water reuse
Investigating nitrate with other constituents in groundwater in two contrasting tropical highland watersheds
Nitrate is globally the most widespread and widely studied groundwater contaminant. However, few studies have been conducted in sub-Saharan Africa, where the leaching potential is enhanced during the rainy monsoon phase. The few monitoring studies found concentrations over drinking water standards of 10 mg N-NO3 - L -1 in the groundwater, the primary water supply in rural communities. Studies on nitrate movement are limited to the volcanic Ethiopian highlands. Therefore, this study aimed to evaluate the transport and fate of nitrate in groundwater and identify processes that control the concentrations. Water table height, nitrate, chloride, ammonium, reduced iron, and three other groundwater constituents were determined monthly in the groundwater in over 30 wells in two contrasting volcanic watersheds over two years in the Ethiopian highlands. The first watershed was Dangishta, with lava intrusion dikes that blocked the subsurface flow in the valley bottom. The water table remained within 3 m of the surface. The second watershed without volcanic barriers was Robit Bata. The water table dropped rapidly within three months of the end of the rain phase and disappeared except near faults. The average nitrate concentration in both watersheds was between 4 and 5 mg N-NO3 - L -1 . Hydrogeology influenced the transport and fate of nitrogen. In Dangishta, water was blocked by volcanic lava intrusion dikes, and residence time in the aquifer was larger than in Robit Bata. Consequently, nitrate remained high (in several wells, 10 mg N-NO3 - L -1 ) and decreased slowly due to denitrification. In Robit Bata, the water residence time was lower, and peak concentrations were only observed in the month after fertilizer application; otherwise, it was near an average of 4 mg N-NO3 - L -1 . Nitrate concentrations were predicted using a multiple linear regression model. Hydrology explained the nitrate concentrations in Robit Bata. In Dangishta, biogeochemistry was also significant.
Runoff / Fertilizers / Ammonia / Chlorides / Rainfall / Precipitation / Wells / Aquifers / Volcanic areas / Highlands / Watersheds / Nitrates / Groundwater table
Expanding water reuse in the Middle East and North Africa: policy report
Social aspects / Women / Gender-transformative approaches / Stakeholders / Business models / Cost recovery / Financing / Sustainability / Health hazards / Water quality standards / Agricultural water use / Irrigation water / Guidelines / Planning / Water governance / Water policies / Resource recovery / Municipal wastewater / Wastewater treatment / Water scarcity / Water availability / Water resources / Water reuse
Implementing conjunctive management of water resources for irrigation development: a framework applied to the Southern Plain of western Nepal
Climate variability and insufficient irrigation are primary constraints to stable and higher agricultural productivity and food security in Nepal. Agriculture is the largest global freshwater user, and integration of surface- and ground-water use is frequently presented as an strategy for increasing efficiency as well as climate change adaptation. However, conjunctive management (CM) planning often ignores demand-side requirements and a broader set of sustainable development considerations, including ecosystem health and economics of different development strategies. While there is generic understanding of conjunctive use, detailed technical knowhow to realize the CM is lacking in Nepal. This article presents a holistic framework through literature reviews, stakeholders consultations and expert interviews for assessing CM and implementation prospects from a systems-level perspective. We demonstrate the framework through a case study in Western Nepal, where climatic variability and a lack of irrigation are key impediments to increased agricultural productivity and sustainable development. Results show that knowledge of water resources availability is good and that of water demand low in the Western Terai. Additional and coordinated investments are required to improve knowledge gaps as well as access to irrigation. There is therefore a need to assess water resources availability, water access, use and productivity, to fill the knowledge gaps in order to pave pathways for CM. This paper also discusses some strategies to translate prospects of conjunctive management into implementation.
Case studies / Capacity development / Awareness / Social inclusion / Gender equity / Stakeholders / Water governance / Energy sources / Monitoring / Strategies / Planning / Sustainable Development Goals / Agricultural productivity / Food security / Water policies / Water productivity / Water demand / Water availability / Surface water / Groundwater / Climate change / Irrigation systems / Conjunctive use / Water use / Water management / Water resources
Scaling best-fit irrigation bundles in Mali: a pathway for improved development outcomes. Adaptive Innovation Scaling - Pathways from Small-scale Irrigation to Sustainable Development
Non-governmental organizations / Food security / Social inclusion / Stakeholders / Credit / Financing / Investment / Profitability / Marketing channels / Market access / Farm income / Agricultural extension / Women farmers / Agricultural resources / Water storage / Pumps / Irrigation equipment / Solar powered irrigation systems / Innovation adoption / Technology / Farmer-led irrigation / Irrigation practices / Irrigated farming / Crop production / Agricultural value chains / Vegetables / Sustainable development / Innovation scaling / Small-scale irrigation
Application of geomorphometric characteristics to prioritize watersheds for soil and water conservation practices in the Lake Tana Basin, Ethiopia
This study employed geomorphometric analysis to characterize the four major watersheds (Gilgel Abay, Gumara, Rib, and Megech) of Lake Tana sub-basin, Ethiopia, and prioritize the watersheds for the implementation of SWC practices using GIS and remote sensing techniques. Also, the study analyzed streamflow and sediment data recorded at the outlets of each watershed to associate the geomorphometric prioritization result with recordings of the watersheds. Geomorphometric analysis results indicated that the Rib watershed is the most susceptible watershed for soil erosion and should be prioritized for the implementation of SWC practices. The analysis of streamflow and suspended sediment concentration suggest that the Rib watershed had the second maximum sediment yield (14.3 t ha-1 yr-1) compared to the other three watersheds. This is because of the low streamflow response of the watershed compared with the Gumara watershed which had the highest sediment yield (18.9 t ha-1 yr-1).
Lakes / Resuspended sediments / Soil erosion / Remote sensing / Geographical information systems / Water conservation / Soil conservation / Watersheds
Sustainable and inclusive scaling of irrigation technologies and services in Ethiopia. Adaptive Innovation Scaling - Pathways from Small-scale Irrigation to Sustainable Development
Intervention / Partnerships / Informal organizations / Private sector / Stakeholders / Youth / Women / Gender / Social inclusion / Value chains / Supply chains / Irrigated farming / Strategies / Regulations / Agricultural financial policy / Water policies / Agricultural water management / Farmer-led irrigation / Smallholders / Sustainable development / Innovation scaling / Technology / Small-scale irrigation
Estimation of shallow groundwater abstraction for irrigation and its impact on groundwater availability in the Lake Tana Sub-basin, Ethiopia
Study region: Lake Tana sub-basin of the Upper Blue Nile River Basin, Ethiopia. Study focus: Groundwater use for small-scale irrigation is increasing in the Lake Tana sub-basin. However, the abstraction amount and its impact are not well understood. In this study, a new methodological approach was utilized to estimate the irrigation water abstraction amount, which is based on groundwater level monitoring before, during, and at the end of the irrigation season (2021/2022). The monitoring was conducted on 361 hand-dug wells distributed throughout the sub-basin, which is subdivided into East, Southwest, and North zones. New hydrological insights for the region: Groundwater abstraction for irrigation and associated groundwater level decline estimates are 10.6 × 106 m3 and 2.43 m in the East, 4.2 × 106 m3 and 3.23 m in the Southwest, and 0.6 × 106 m3 and 1.32 m in the North. These abstractions account for 103%, 97%, and 62% of the mean annual groundwater recharge in the East, Southwest, and North zones, respectively. Groundwater is overexploited in the East and Southwest zones although, at the sub-basin scale, the amount of groundwater used for irrigation is small compared to the renewable groundwater resource. However, if groundwater-based irrigation continues to expand especially in the East and Southwest zones, groundwater scarcity at the local scales will worsen. Adaptive management strategies are required to minimize the potential adverse effects on groundwater resources.
Dry season / Wells / Lakes / Sediment / Aquifers / Irrigated land / Water supply / Surface water / Water use / Small-scale irrigation / Water levels / Monitoring / Groundwater table / Groundwater recharge / Water availability / Shallow water / Groundwater irrigation / Groundwater extraction
Shifting waters: the challenges of transitioning from freshwater to treated wastewater irrigation in the northern Jordan Valley
Jordan’s water scarcity prompted a national plan whereby treated wastewater is utilized to amend agricultural irrigation water so as to reallocate freshwater to urban/domestic uses. The policy, however, has engendered farmers’ resistance in the Northern Jordan Valley (NJV), causing a stalemate in putting new infrastructure into operation. This research investigated the socio-economic causes of farmer resistance and contestation, and examined the government’s institutional approach to overcome the challenges. We found that the perceived risks of wastewater reuse such as salinization and restrictions from international markets figure prominently in the farmers resistance. As yet, farmers have managed to avoid the shift to treated wastewater use by using the political agency of elite farmers who control the Water Users Associations. These same farmers have adopted informal water access practices to overcome freshwater shortages. At the same time, small producers who don’t have possibilities to access extra water and with less political clout seem more willing to irrigate with treated wastewater. We conclude that understanding the heterogeneous context in which the envisioned wastewater users operate is key to predicting and solving conflicts that arise in treated wastewater reuse projects.
Socioeconomic aspects / Farmers / Water user associations / Stakeholders / Water policies / Water scarcity / Urban areas / Water management / Infrastructure / Irrigation water / Freshwater / Water allocation / Water reuse / Wastewater irrigation
Do needs motivate the exchange of data in transboundary waters? Insights from Africa’s shared basins
Despite widespread recognition of the importance of data exchange in transboundary waters’ management, there is growing evidence that data exchange is falling short in practice. A possible explanation may be that data exchange occurs where and when it is needed. Needs for data exchange in shared waters, nonetheless, have not been systematically assessed. This paper evaluates data exchange needs in a set of transboundary basins and compares such needs with evidenced levels of data exchange. Our findings indicate that it may be possible to accelerate data exchange by identifying and promoting the exchange of data that respond to palpable need and serve practical use.
Environmental factors / Hydropower / Agriculture / Water supply / Urban areas / Water quality / Treaties / International agreements / Water management / Water resources / Assessment / Information exchange / Data / River basins / Transboundary waters
Economic valuation of restoring and conserving ecosystem services of Indian Sundarbans
Conservation of forest ecosystem is fundamental for economic-ecological sustainability. Indian Sundarbans provide several ecosystem services, which needs sustainable exploitation since forest dwellers are heavily dependent on the forest. In our study, we attempt to estimate the option value of the forest dwellers through a non-market based valuation technique. Using contingent valuation, we seek to estimate the contribution forest fringe dwellers are ready to provide for restoration and conservation of the ecosystem services. Assuming a random utility framework, mean willingness to pay is estimated from the forest dwellers’ responses to the Dichotomous Choice bidding as well as open-ended bidding question using socio-economic variables which determine the value towards forest ecosystem services. The results indicate that forest dwellers have a positive option value and hence are willing to forgo present extraction of forest resources for future use. This value the forest dwellers associate with non-use ecosystem services indicates their willingness to participate in forest conservation. The study therefore concludes that institutions like Joint Forest Management should be promoted for efficient management of the mangrove in providing livelihood and ecosystem services.
Mangroves / Participatory approaches / Communities / Socioeconomic aspects / Households / Livelihoods / Willingness to pay / Economic value / Contingent valuation / Environmental restoration / Forest conservation / Ecosystem services
Filling streamflow data gaps through the construction of rating curves in the Lake Tana Sub-basin, Nile Basin
In recent decades, streamflow data remain inaccessible for most river gauges in Ethiopia due to a lack of updated stage–discharge relationships, also called rating curves. In this study, researchers and hydrologic technicians collaborated to fill the recent streamflow data gaps at three gauging stations in the Lake Tana sub-basin of the Nile River. We conducted extensive field campaigns to improve the coverage of stage–discharge measurements for rating curve development. We evaluated the rating curve uncertainty during the time of its establishment and the sensitivity of the rating curves to sample size. The stage–discharge measurements conducted by the hydrological agency during the period 2016–2020 were found inadequate in number and coverage to establish reliable rating curves. Hence, converting recent water level measurements to discharge data was made possible using the rating curves developed in this study. The converted discharge data will be accessible to researchers to investigate the sub-basin’s hydrology. Our study emphasizes the need to improve the stage–discharge measurement frequency to keep up with the frequent change in the morphology of the rivers’ channels. The study demonstrated that collaboration between the data provider and data users can improve streamflow data availability and accessibility, which has become an increasing global challenge.
Collaboration / Hydrology / Catchment areas / Lakes / Rivers / Tributaries / Monitoring / Water levels / Discharges / Stream flow
Diversifying agrifood systems to ensure global food security following the Russia–Ukraine crisis
The recent Russia–Ukraine conflict has raised significant concerns about global food security, leaving many countries with restricted access to imported staple food crops, particularly wheat and sunflower oil, sending food prices soaring with other adverse consequences in the food supply chain. This detrimental effect is particularly prominent for low-income countries relying on grain imports, with record-high food prices and inflation affecting their livelihoods. This review discusses the role of Russia and Ukraine in the global food system and the impact of the Russia–Ukraine conflict on food security. It also highlights how diversifying four areas of agrifood systems—markets, production, crops, and technology can contribute to achieving food supply chain resilience for future food security and sustainability.
Conflicts / Technology / Exports / Markets / Food prices / Resilience / Food supply chains / Food production / Food crops / Sustainable intensification / Diversification / Agrifood systems / Food security
Assessing the prospects of remote sensing maize leaf area index using UAV-derived multi-spectral data in smallholder farms across the growing season
Maize (Zea Mays) is one of the most valuable food crops in sub-Saharan Africa and is a critical component of local, national and regional economies. Whereas over 50% of maize production in the region is produced by smallholder farmers, spatially explicit information on smallholder farm maize production, which is necessary for optimizing productivity, remains scarce due to a lack of appropriate technologies. Maize leaf area index (LAI) is closely related to and influences its canopy physiological processes, which closely relate to its productivity. Hence, understanding maize LAI is critical in assessing maize crop productivity. Unmanned Aerial Vehicle (UAV) imagery in concert with vegetation indices (VIs) obtained at high spatial resolution provides appropriate technologies for determining maize LAI at a farm scale. Five DJI Matrice 300 UAV images were acquired during the maize growing season, and 57 vegetation indices (VIs) were generated from the derived images. Maize LAI samples were collected across the growing season, a Random Forest (RF) regression ensemble based on UAV spectral data and the collected maize LAI samples was used to estimate maize LAI. The results showed that the optimal stage for estimating maize LAI using UAV-derived VIs in concert with the RF ensemble was during the vegetative stage (V8–V10) with an RMSE of 0.15 and an R2 of 0.91 (RRMSE = 8%). The findings also showed that UAV-derived traditional, red edge-based and new VIs could reliably predict maize LAI across the growing season with an R2 of 0.89–0.93, an RMSE of 0.15–0.65 m2/m2 and an RRMSE of 8.13–19.61%. The blue, red edge and NIR sections of the electromagnetic spectrum were critical in predicting maize LAI. Furthermore, combining traditional, red edge-based and new VIs was useful in attaining high LAI estimation accuracies. These results are a step towards achieving robust, efficient and spatially explicit monitoring frameworks for sub-Saharan African smallholder farm productivity.
Crop yield / Agricultural productivity / Machine learning / Models / Forecasting / Monitoring / Growth stages / Smallholders / Small-scale farming / Multispectral imagery / Unmanned aerial vehicles / Remote sensing / Vegetation index / Leaf area index / Maize
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