Your search found 20 records
1 Sutherland, A.; Martin, A.; Smith, D. R. 2001. Dimensions of participation: experiences, lessons and tips from agricultural research practitioners in Sub-Saharan Africa. Chatham, UK: University of Greenwich. Natural Resources Institute (NRI). 328p.
Agricultural research ; Farmer participation ; Participatory approaches ; Experimentation ; Training ; Information dissemination ; Farming systems ; Public sector ; Non governmental organizations ; Institutions ; Corporate culture ; Stakeholders ; Projects ; Case studies / Africa South of Sahara
(Location: IWMI HQ Call no: 630.7 G000 SUT Record No: H046727)
(0.54 MB)
2 Estabragh, A. R.; Moghadas, M.; Javadi, A. A. 2016. Hydrochemical effect of different quality of water on the behaviour of an expansive soil during wetting and drying cycles. Irrigation and Drainage, 65(3):371-381. [doi: https://doi.org/10.1002/ird.1974]
Water quality ; Hydrology ; Chemical composition ; Reservoirs ; Pore water ; Expansive Soils ; Wetting drying cycles ; pH ; Electrical conductivity ; Osmotic pressure ; Deformation ; Experimentation ; Flooding ; Distilled water ; Acidic Water ; Saline water
(Location: IWMI HQ Call no: e-copy only Record No: H047654)
(1.07 MB)
The effect of quality of water on deformation, pH, EC (electrical conductivity) and osmotic suction was studied for an expansive soil during wetting and drying tests. The cyclic wetting and drying tests were conducted on samples of an expansive soil in a modified oedometer flooded with distilled, acidic and saline water. During the tests axial deformation of the samples was recorded continuously. pH and EC of pore water and reservoir water were measured through duplicated samples in a conventional oedometer. Osmotic suction was calculated based on the values of EC. The results show that the magnitude of deformation depends on the quality of the water and the deformation attained an equilibrium condition after almost four cycles. pH, EC and osmotic suction decreased with increasing suction.
3 Surendran, U.; Sandeep, O.; Joseph, E. J. 2016. The impacts of magnetic treatment of irrigation water on plant, water and soil characteristics. Agricultural Water Management, 178:21-29. [doi: https://doi.org/10.1016/j.agwat.2016.08.016]
Irrigation water ; Wastewater treatment ; Magnetic water ; Saline water ; Magnetic field ; Experimentation ; Drip irrigation ; Soil moisture ; Electrical conductivity ; pH ; Total dissolved solids ; Plant growth ; Crop yield ; Cowpeas ; Brinjal / India / Kerala / Kozhikode
(Location: IWMI HQ Call no: e-copy only Record No: H047850)
(2.24 MB)
Magnetic treatment has remained a controversial process for antiscale treatment of industrial and domestic water treatment over the past many years. Hence a study was initiated to evaluate the magnetic treatment of irrigation water on growth and yield parameters of cow pea and brinjal using pot and field experiments. Also, the impact of magnetic treatment on water properties and soil moisture were also evaluated. Under pot experiment, the treatments tried are normal water, hard water 150 and 300 ppm, saline water 500, 1000 and 2000 ppm of both control and magnetic treated solutions, respectively. Two permanent magnets with the strength of 1800–2000 G was used. The results showed that magnetic treatment of irrigation water types led to an improvement in crop growth and yield parameters of cow pea. Magnetic treatments tend to reduce electrical conductivity, total dissolved solids and salinity levels of all solutions except normal irrigation water, whereas a definite trend of increase in pH was noticed for all the treatments. Soil moisture study results showed that the differences in soil moisture for days 1–3 after irrigation with magnetized irrigation water were lesser than those for the control solutions. Irrigation with magnetized irrigation water caused higher soil moisture compared with the control for different solution of saline and hard water respectively. In the field experiment with brinjal also the magnetic treatment of normal and saline water improved the yield by 25.8 and 17.0% over control. Scanning electron microscope image analysis results confirmed that under magnetic treated hard water, there was variation in the crystal structure of calcium carbonate. The length of these crystals is more when compared to control solutions. These results indicated the beneficial effect of magnetically treated irrigation water on growth and yield of crops, the properties of water and confirmed the possibility of using low quality water for agriculture.
4 Haileselassie, H.; Araya, A.; Habtu, S.; Meles, K. G.; Gebru, G.; Kisekka, I.; Girma, A.; Hadgu, K. M.; Foster, A. J. 2016. Exploring optimal farm resources management strategy for Quncho-teff (Eragrostis tef (Zucc.) Trotter) using AquaCrop model. Agricultural Water Management, 178:148-158. [doi: https://doi.org/10.1016/j.agwat.2016.09.002]
Crop management ; Eragrostis tef ; Irrigation water ; Water productivity ; Models ; Farm management ; Strategies ; Crop yield ; Fertilizer application ; Sowing date ; Soil water characteristics ; Chemicophysical properties ; Rain ; Biomass ; Canopy ; Experimentation / Ethiopia / Mekelle
(Location: IWMI HQ Call no: e-copy only Record No: H047852)
(1.52 MB)
Teff is a major staple food crop in Ethiopia. Moisture and soil fertility are the two major factors limiting teff yield. Studies were conducted across three sites in Ethiopa [Mekelle (MK) in 2012 and 2016, Ilala (IL) in 2012 and Debrezeit (DZ) in 2009 and 2010]. The objectives of these studies were (1) to assess the response of Quncho-teff to different fertilizer and irrigation levels; 2) to quantify irrigation water productivity (IWP), and (3) to collect data to calibrate and validate AquaCrop model for simulating yield and evaluate optimal irrigation and sowing date strategy for Quncho-teff at different locations in Ethiopia. The different fertilizer levels were: 1) 64 kg N and 46 kg P/ha (N2P2); 2); 32 kg N and 23 kg P/ha (N1P1); 3) 0 kg N and 0 kg P/ha (N0P0) and 4) 52 kg N and 46 kg P/ha (N3P3). The four irrigation treatments were: zero (rainfed), two, four and full irrigation applications. Findings showed that full irrigation in combination with high fertilizer (N2P2) could give better yield. However, during abnormal rainfall, spreading the available fertilizer at a rate of 32 kg N and 23 kg P/ha may be preferable to applying 64 kg N and 46 kg P/ha. This study also indicated that the regional fertilizer recommendations for teff need to be revised taking in to account the soil characteristics, climate and irrigation water availability. The AquaCrop model was able to simulate the observed canopy cover, soil water, biomass and yield of teff satisfactorily. Canopy cover was simulated with normalized root mean square error (NRMSE), index of agreement (I) and R2 of 7%, 0.5 and 0.8, respectively. Soil moisture during the season was simulated with NRMSE of 11.4–15.7%, I of 0.99 and R2 of 0.85–0.9. Simulated final aboveground biomass values were in close agreement with the measured (NRMSE, 7.8%, I, 0.89 and R2, 0.66). There was also good agreement between simulated and measured grain yield with NRMSE, I and R2 values of 10.9%, 0.93, 0.80, respectively. Scenario analysis indicated that early sowing was the best option to maximize teff yield with the least amount of irrigation. Scenario analysis also showed that one irrigation during flowering stage could substantially improve irrigation water productivity (IWP) of teff and minimize the yield loses which could occur due to shifting of sowing date from early to normal. Two irrigation applications also substantially improved the yield and IWP of late sown teff. However, to get high yield, a late sown teff should receive at least four irrigation applications during the mid-growth stage of the crop. These results suggest that AquaCrop model can be used to identify optimal farm resource management strategies for teff production.
5 Becchetti, L.; Castriota, S.; Conzo, P. 2017. Disaster, aid, and preferences: the long-run impact of the tsunami on giving in Sri Lanka. World Development, 94:157-173. [doi: https://doi.org/10.1016/j.worlddev.2016.12.014]
Natural disasters ; Tsunamis ; Disaster recovery ; Development aid ; Social behaviour ; Attitudes ; Financial institutions ; Microfinance ; Loans ; Socioeconomic environment ; Econometrics ; Sensitivity analysis ; Regression analysis ; Villages ; Experimentation / Sri Lanka / Galle / Matara / Hambantota
(Location: IWMI HQ Call no: e-copy only Record No: H048148)
(0.38 MB)
Do natural disasters produce effects on preferences of victims in the long run? We test the impact of the tsunami shock on generosity of a sample of Sri Lankan affected/unaffected microfinance borrowers seven years after the event.
Specifically, we test the effect of the shock at the extensive margin by comparing damaged with non-damaged individuals in terms of giving and expected giving in a dictator game. Moreover, at the intensive margin, we compare the participants based on the amount of damage experienced and recovery aid received. The advantage of this last comparison is that differences in observables between the groups are minimized. We reduce further identification problems by selecting a random sample of damaged and non-damaged borrowers belonging to the same microfinance organization who are, therefore, likely to share some important common traits that are usually unobservable to researchers. We complete our identification strategy with weighted least squares, instrumental variable estimates and a sensitivity analysis on the exogeneity assumption.
The main findings of the paper support the hypothesis that the shock affects participants’ preferences in the long run. First, the tsunami negatively affects generosity at the extensive margin as those who suffered at least one damage give and expect less than those who did not. Second, while large recovery assistance does not directly affect giving and expected giving, it increases especially the latter indirectly, i.e., when interacted with the number of damages.
Our results reconcile that part of the literature showing evidence of natural shocks having a detrimental effect on social preferences (Fleming, Chong, Alberto, & Bejarano, 2011; Cassar, Grosjean, & Whitt, 2013) with that supporting, instead, a positive link (Solnit, 2009; Whitt & Wilson, 2007; Cassar, Healy, & Von Kessler, 2011). Furthermore, since our study focuses on the long-run impact of a natural disaster, previous results on short-run effects are not necessarily inconsistent with ours.
Specifically, we test the effect of the shock at the extensive margin by comparing damaged with non-damaged individuals in terms of giving and expected giving in a dictator game. Moreover, at the intensive margin, we compare the participants based on the amount of damage experienced and recovery aid received. The advantage of this last comparison is that differences in observables between the groups are minimized. We reduce further identification problems by selecting a random sample of damaged and non-damaged borrowers belonging to the same microfinance organization who are, therefore, likely to share some important common traits that are usually unobservable to researchers. We complete our identification strategy with weighted least squares, instrumental variable estimates and a sensitivity analysis on the exogeneity assumption.
The main findings of the paper support the hypothesis that the shock affects participants’ preferences in the long run. First, the tsunami negatively affects generosity at the extensive margin as those who suffered at least one damage give and expect less than those who did not. Second, while large recovery assistance does not directly affect giving and expected giving, it increases especially the latter indirectly, i.e., when interacted with the number of damages.
Our results reconcile that part of the literature showing evidence of natural shocks having a detrimental effect on social preferences (Fleming, Chong, Alberto, & Bejarano, 2011; Cassar, Grosjean, & Whitt, 2013) with that supporting, instead, a positive link (Solnit, 2009; Whitt & Wilson, 2007; Cassar, Healy, & Von Kessler, 2011). Furthermore, since our study focuses on the long-run impact of a natural disaster, previous results on short-run effects are not necessarily inconsistent with ours.
6 Kumar, M.; Kumar, R.; Rajput, T. B. S.; Patel, N. 2017. Efficient design of drip irrigation system using water and fertilizer application uniformity at different operating pressures in a semi-arid region of India. Irrigation and Drainage, 66(3):316-326. [doi: https://doi.org/10.1002/ird.2108]
Irrigation systems ; Drip irrigation ; Water use ; Fertilizer application ; Performance evaluation ; Irrigation water ; Water distribution ; Nutrients ; Water quality ; Chemicophysical properties ; Discharges ; Uniformity coefficient ; Semiarid zones ; Experimentation / India / New Delhi
(Location: IWMI HQ Call no: e-copy only Record No: H048187)
(0.92 MB)
Performance evaluation of irrigation has been an important area of research for better management of water resources. The present study was conducted to evaluate the effect of drip lateral lengths and system operating pressures on water and fertilizer application uniformity at the Indian Agricultural Research Institute (IARI), New Delhi, India. The following parameters of nutrients and water were studied to design and evaluate the performance of drip irrigation systems: (i) uniformity coefficient; (ii) discharge variation; (iii) distribution uniformity; (iv) statistical uniformity. Drip-line lengths and system operating pressures (P < 0.05 and P < 0.01) significantly affect the different parameters of fertilizer and water application. The highest values of uniformity coefficient (99.2%), statistical uniformity (99.2%) and distribution uniformity (97.4%) for irrigation water were observed at a pressure of 1.5 kg cm 2 with a 25 m long drip-line. Lower values of discharge variation (2.65%) and coefficient of variation (0.04) were observed at the same operating pressure (1.5 kg cm 2 ) and drip-line length. However, the lowest value of the uniformity coefficient (88.1%), statistical uniformity (93.7%) and distribution uniformity (93.2%) for irrigation water were recorded at 0.5 kg cm 2 pressure with a 100 m long drip-line length. The highest values of urea, potassium and phosphorus distribution uniformity were found to be 97.8, 97.1 and 98.2%, respectively, at 1.5 kg cm 2 pressure with 25 m long drip-line, and lower values of urea, potassium and phosphorus distribution uniformity (93.1, 92.6 and 93.2%, respectively) were recorded at 0.5 kg cm 2 pressure with a 100 m long drip-line. Water and fertilizer distribution uniformity decreased with increase in drip-line length, and increased with increase in system operating pressure.
7 Okyere, C. Y.; Asante, F. A. 2017. Perceptions and determinants of households’ participation in a randomized evaluation on water quality testing and information in southern Ghana. Water Policy, 19(6):1206-1224. [doi: https://doi.org/10.2166/wp.2017.177]
Water quality ; Testing ; Households ; Attitudes ; Community involvement ; Wastewater treatment ; Information dissemination ; Evaluation techniques ; Experimentation ; Training ; Socioeconomic environment / Africa / Ghana / Shai-Osudoku District / Ga South Municipal
(Location: IWMI HQ Call no: e-copy only Record No: H048382)
(0.14 MB)
In this paper, we analyze perceptions and determinants of households’ participation in a randomized experiment on water quality testing and information in southern Ghana. Beneficiary households assessed the components of the intervention including its relevance and adequacy in improving understanding of water quality issues. Motivating and constraining factors to participation in the randomized experiment are also assessed. We also estimate the correlates of participation in the intervention. Social and economic benefits derived from the intervention based on perceptions are compared with impacts of the intervention using an instrumental variable approach. We found evidence that subjective analysis estimates of the effects of the intervention are higher than the objective analysis estimates. Households generally perceived the intervention to be relevant in improving their understanding of water quality issues. However, there are differing opinions based on random assignment into either child or adult treatment groups on most- and least-liked attributes of the intervention, and also motivating and constraining factors affecting participation in the intervention. The factors that statistically and significantly influenced participation in the intervention include educational attainment, ethnicity, religious denomination and marital status of the household heads, in addition to the location of residence.
8 Meinzen-Dick, R.; Janssen, M. A.; Kandikuppa, S.; Chaturvedi, R.; Rao, K.; Theis, S. 2018. Playing games to save water: collective action games for groundwater management in Andhra Pradesh, India. World Development, 107:40-53. [doi: https://doi.org/10.1016/j.worlddev.2018.02.006]
Groundwater management ; Water conservation ; Collective action ; Game theory ; Human behaviour ; Experimentation ; Groundwater table ; Crops ; Stakeholders ; Nongovernmental organizations ; Research organizations ; Communities ; Models / India / Andhra Pradesh
(Location: IWMI HQ Call no: e-copy only Record No: H048587)
https://www.sciencedirect.com/science/article/pii/S0305750X18300445/pdfft?md5=edf7de8abb3f4dffd9577674b0b40969&pid=1-s2.0-S0305750X18300445-main.pdf
https://vlibrary.iwmi.org/pdf/H048587.pdf
https://vlibrary.iwmi.org/pdf/H048587.pdf
(0.93 MB) (952 KB)
Groundwater is one of the most challenging common pool resources to govern, resulting in resource depletion in many areas. We present an innovative use of collective action games to not only measure propensity for cooperation, but to improve local understanding of groundwater interrelationships and stimulate collective governance of groundwater, based on a pilot study in Andhra Pradesh, India. The games simulate crop choice and consequences for the aquifer. These were followed by a community debriefing, which provided an entry point for discussing the interconnectedness of groundwater use, to affect mental models about groundwater. A slightly modified game was played in the same communities, one year later. Our study finds communication within the game increased the likelihood of groups reaching sustainable extraction levels in the second year of play, but not the first. Individual payments to participants based on how they played in the game had no effect on crop choice. Either repeated experience with the games or the revised structure of the game evoked more cooperation in the second year, outweighing other factors influencing behavior, such as education, gender, and trust index scores. After the games were played, a significantly higher proportion of communities adopted water registers and rules to govern groundwater, compared to other communities in the same NGO water commons program. Because groundwater levels are affected by many factors, games alone will not end groundwater depletion. However, games can contribute to social learning about the role of crop choice and collective action, to motivate behavior change toward more sustainable groundwater extraction.
9 Kumar, T.; Post, A. E.; Ray, I. 2018. Flows, leaks and blockages in informational interventions: a field experimental study of Bangalore’s water sector. World Development, 106:149-160. [doi: https://doi.org/10.1016/j.worlddev.2018.01.022]
Water supply ; Information dissemination ; Households ; Social welfare ; Income ; Pipes ; Political aspects ; Transparency ; Population ; Socioeconomic environment ; Psychological factors ; Stress ; Experimentation / India / Bangalore
(Location: IWMI HQ Call no: e-copy only Record No: H048795)
(1.14 MB)
Many policies and programs based on informational interventions hinge upon the assumption that providing citizens with information can help improve the quality of public services, or help citizens cope with poor services. We present a causal framework that can be used to identify leaks and blockages in the information production and dissemination process in such programs. We conceptualize the "information pipeline" as a series of connected nodes, each of which constitutes a possible point of blockage. We apply the framework to a field-experimental evaluation of a program that provided households in Bangalore, India, with advance notification of intermittently provided piped water. Our study detected no impacts on household wait times for water or on how citizens viewed the state, but found that notifications reduced stress. Our framework reveals that, in our case, noncompliance among human intermediaries and asymmetric gender relations contributed in large part to these null-to-modest results. Diagnostic frameworks like this should be used more extensively in development research to better understand the mechanisms responsible for program success and failure, to identify subgroups that actually received the intended treatment, and to identify potential leaks and blockages when replicating existing programs in new settings.
10 Jordan, A.; Huitema, D.; van Asselt, H.; Forster, J. (Eds.) 2018. Governing climate change: polycentricity in action? Cambridge, UK: Cambridge University Press. 389p. [doi: https://doi.org/10.1017/9781108284646]
Climate change adaptation ; Governance ; International agreements ; Environmental conventions ; UNFCCC ; International organizations ; Environmental organizations ; State intervention ; Regulations ; International law ; Environmental policies ; Carbon markets ; Entrepreneurship ; Economic aspects ; Technology transfer ; Innovation ; Experimentation ; Energy technology ; Solar energy ; Towns ; Political aspects ; Equity ; Leadership ; Diffusion ; Monitoring ; Evaluation ; Learning
(Location: IWMI HQ Call no: e-copy only Record No: H048770)
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/033486F6DA7F2CD1F8F3D6011B17909B/9781108418126AR.pdf/Governing_Climate_Change.pdf?event-type=FTLA
https://vlibrary.iwmi.org/pdf/H048770.pdf
https://vlibrary.iwmi.org/pdf/H048770.pdf
(6.89 MB) (6.89 MB)
11 High, H. 2013. Experimental consensus: negotiating with the irrigating state in the South of Laos. Asian Studies Review, 37(4):491-508. [doi: https://doi.org/10.1080/10357823.2013.794188]
Irrigation management ; Agreements ; Political aspects ; Economic aspects ; Policy ; Experimentation ; Farmers ; Living standards ; Poverty ; Villages / Lao People's Democratic Republic / Don Khiaw
(Location: IWMI HQ Call no: e-copy only Record No: H048825)
(0.24 MB)
It is common to view Laos as a political culture prone to “consensus”, yet it is also true that policy is constantly changing there, often radically. If everyone is always “in consensus”, what can explain this change? I suggest that the answer is found in the particular kind of consensus at play: it is informed by a wider “experimentarian” ethic evident in rural Laos, where ideas (including the latest policies) are put to the test through practical implementation. The results of these experiments are used to validate policy change and reversal. This allows rural residents a degree of manoeuvrability in their engagements with the state that is striking given the “authoritarian” status of the current regime. It can explain and is used to justify, for instance, the oft-observed gap between policy and actual practice. This room for manoeuvre comes at the price of “playing the game”, at least for a while, of the latest policy fad, sometimes with disastrous consequences for rural livelihoods. I use the example of an irrigation project that was implemented in the south of Laos from 1999–2002 to examine “experimental consensus” at work as policy was received, engaged and eventually relinquished.
12 McCord, P.; Waldman, K.; Baldwin, E.; Dell’Angelo, J.; Evans, T. 2018. Assessing multi-level drivers of adaptation to climate variability and water insecurity in smallholder irrigation systems. World Development, 108:296-308. [doi: https://doi.org/10.1016/j.worlddev.2018.02.009]
Climate change adaptation ; Water insecurity ; Smallholders ; Irrigation systems ; Agriculture ; Flow discharge ; Water governance ; Water user associations ; Collective action ; Seeds ; Experimentation ; Households ; Socioeconomic environment / Kenya / Mount Kenya Region
(Location: IWMI HQ Call no: e-copy only Record No: H048849)
(1.45 MB)
Smallholder agriculturalists employ a range of strategies to adapt to climate variability. These adaptive strategies include decisions to plant different seed varieties, changes to the array of cultivated crops, and shifts in planting dates. Smallholder access to irrigation water is crucial to the adoption of such strategies, and uncertainty of water availability may prove to be a stimulating force in a smallholder’s decision to adjust their on-farm practices. Within smallholder irrigation systems, attributes at multiple levels influence water availability and collective action, and in the process play a role in adaptation: community-level governance institutions may influence trust in others and the ability to overcome appropriation and provisioning dilemmas, and, at the household-level, the availability of irrigation water and socioeconomic and demographic factors may influence farmer willingness to take on the risk of altering their on-farm practices. In this study we investigate smallholder adaptation in Kenya from multiple levels. Specifically, we identify the role of household- and community-level characteristics in shaping smallholder experimentation with different seed varieties. Standard ordinary least squares and logistic regressions are constructed to assess the influence of these interactions on smallholder adaptation. We further discuss the ability of smallholders to respond to poor water provisioning. Among the study’s findings is evidence that smallholders are more willing to employ adaptive measures if they have a limited capacity to irrigate.
13 Yates, J. S.; Harris, L. M. 2018. Hybrid regulatory landscapes: the human right to water, variegated neoliberal water governance, and policy transfer in Cape Town, South Africa, and Accra, Ghana. World Development, 110:75-87. [doi: https://doi.org/10.1016/j.worlddev.2018.05.021]
Water availability ; Human rights ; Water supply ; Water governance ; Water policy ; Regulations ; Water management ; Water demand ; User charges ; Social aspects ; Environmental effects ; Economic aspects ; Constraints ; Experimentation / South Africa / Ghana / Cape Town / Accra
(Location: IWMI HQ Call no: e-copy only Record No: H048923)
(0.42 MB)
Drawing on an analysis of water access and supply in Cape Town (South Africa) and Accra (Ghana), we illustrate that neoliberal and human right to water-oriented transformations co-constitute each other discursively, practically, and in policy implementation. Focusing on the transfer of policies and experiences (particularly conjoined demand management-free basic water programs and related social contestation), we provide examples of how neoliberal logics and human right to water principles intersect in evolving hybrid regulatory landscapes, which are characterized by contradiction. The human right to water makes a difference by influencing the drafting and implementation of water-related policies that affect to the lives of poor and vulnerable populations. Yet this process unfolds unevenly, as human right to water principles and practices are contextually applied, often alongside neoliberalizing policy instruments within evolving regulatory landscapes. Our analysis reveals the uneven effects of policy experimentation, transfer, and adaptation. The analysis shows that the principle of the human right to water affects the transformation of policy options circulating in the water sector, but it does so in relation to the institutional histories and policy options associated with uneven patterns of variegated neoliberalization in the water sector.
14 Mazzucato, M.; European Commission. Directorate-General for Research and Innovation. 2018. Mission-oriented research and innovation in the European Union: a problem-solving approach to fuel innovation-led growth. Luxembourg City, Luxembourg: Publications Office of the European Union. 30p. [doi: https://doi.org/10.2777/360325]
Research projects ; Innovation policies ; European Union ; Research policies ; Applied research ; Experimentation ; Problem solving ; Stakeholders ; Public participation ; Implementation ; Economic growth ; Public health ; Strategies ; Social aspects ; Oceans
(Location: IWMI HQ Call no: e-copy only Record No: H049066)
https://ec.europa.eu/info/sites/info/files/mazzucato_report_2018.pdf
https://vlibrary.iwmi.org/pdf/H049066.pdf
https://vlibrary.iwmi.org/pdf/H049066.pdf
(0.45 MB) (464 KB)
15 Ma, B.; Xue, W.; Ding, Y.; Hu, C.; Liu, H.; Qu, J. 2019. Removal characteristics of microplastics by fe-based coagulants during drinking water treatment. Journal of Environmental Sciences, 78:267-275. [doi: https://doi.org/10.1016/j.jes.2018.10.006]
Drinking water treatment ; Microplastics ; Ultrafiltration ; Membrane filtration ; Disinfection ; Coagulation ; Experimentation
(Location: IWMI HQ Call no: e-copy only Record No: H049224)
(1.06 MB)
Microplastics have caused great concern worldwide recently due to their ubiquitous presence within the marine environment. Up to now, most attention has been paid to their sources, distributions, measurement methods, and especially their eco-toxicological effects. With microplastics being increasingly detected in freshwater, it is urgently necessary to evaluate their behaviors during coagulation and ultrafiltration (UF) processes. Herein, the removal behavior of polyethylene (PE), which is easily suspended in water and is the main component of microplastics, was investigated with commonly used Fe-based salts. Results showed that although higher removal efficiency was induced for smaller PE particles, low PE removal efficiency (below 15%) was observed using the traditional coagulation process, and was little influenced by water characteristics. In comparison to solution pH, PAM addition played a more important role in increasing the removal efficiency, especially anionic PAM at high dosage (with efficiency up to 90.9%). The main reason was ascribed to the dense floc formation and high adsorption ability because of the positively charged Fe-based flocs under neutral conditions. For ultrafiltration, although PE particles could be completely rejected, slight membrane fouling was caused owing to their large particle size. The membrane flux decreased after coagulation; however, the membrane fouling was less severe than that induced by flocs alone due to the heterogeneous nature of the cake layer caused by PE, even at high dosages of Fe-based salts. Based on the behavior exhibited during coagulation and ultrafiltration, we believe these findings will have potential application in drinking water treatment.
16 Endrie, B.; Schmitter, Petra; Haileslassie, Amare; Desalegn, Y.; Chali, A.; Tilahun, S.; Barron, Jennie. 2019. Feeding hungry and thirsty soils increases yield and protects the environment: some results of a Wetting Front Detectors (WFD) experiment in LIVES [Livestock and Irrigation Value Chains for Ethiopian Smallholders]. In Mekonnen, K.; Yasabu, S.; Gebremedhin, B.; Woldemeskel, E.; Tegegne, A.; Thorne, P. (Eds.). Proceedings of a Workshop and Exhibition on Promoting Productivity and Market Access Technologies and Approaches to Improve Farm Income and Livelihoods in Ethiopia: Lessons from Action Research Projects, Addis Ababa, Ethiopia, 8-9 December 2016. Nairobi, Kenya: International Livestock Research Institute (ILRI). pp.13-17.
Irrigation schemes ; Water management ; Wetting front ; Experimentation ; Reservoirs ; Fertilizer application ; Crop yield ; Soils ; Farmers ; Agricultural practices / Ethiopia / Koga Irrigation scheme / Meki Irrigation scheme
(Location: IWMI HQ Call no: e-copy only Record No: H049335)
https://cgspace.cgiar.org/bitstream/handle/10568/102356/AR_proceedings_2019.pdf?sequence=1&isAllowed=y
https://vlibrary.iwmi.org/pdf/H049335.pdf
https://vlibrary.iwmi.org/pdf/H049335.pdf
(0.16 MB) (6.23 MB)
17 Liu, Y.; Zhang, J.-y.; Elmahdi, Amgad; Yang, Q.-l.; Guan, X.-x.; Liu, C.-s.; He, R.-m.; Wang, G.-q. 2021. Transferability of a lumped hydrologic model, the Xin’anjiang model based on similarity in climate and geography. Water Supply, 21(5):2191-2201. [doi: https://doi.org/10.2166/ws.2021.055]
Hydrology ; Models ; Watersheds ; Catchment areas ; Climatic zones ; Geography ; Rivers ; Runoff ; Discharges ; Precipitation ; Forecasting ; Experimentation / China / Chuzhou / Chengxi Experimental Watershed
(Location: IWMI HQ Call no: e-copy only Record No: H050320)
https://iwaponline.com/ws/article-pdf/21/5/2191/920069/ws021052191.pdf
https://vlibrary.iwmi.org/pdf/H050320.pdf
https://vlibrary.iwmi.org/pdf/H050320.pdf
(0.52 MB) (532 KB)
Hydrological experiments are essential to understanding the hydrological cycles and promoting the development of hydrologic models. Model parameter transfers provide a new way of doing hydrological forecasts and simulations in ungauged catchments. To study the transferability of model parameters for hydrological modelling and the influence of parameter transfers on hydrological simulations, the Xin’anjiang model (XAJ model), which is a lumped hydrologic model based on a saturation excess mechanism that has been widely applied in different climate regions of the world, was applied to a low hilly catchment in eastern China, the Chengxi Experimental Watershed (CXEW). The suitability of the XAJ model was tested in the eastern branch catchment of CXEW and the calibrated model parameters of the eastern branch catchment were then transferred to the western branch catchment and the entire watershed of the CXEW. The results show that the XAJ model performs well for the calibrated eastern branch catchment at both daily and monthly scales on hydrological modelling with the NSEs over 0.6 and the REs less than 2.0%. Besides, the uncalibrated catchments of the western branch catchment and the entire watershed of the CSEW share similarities in climate (the precipitation) and geography (the soil texture and vegetation cover) with the calibrated catchment, the XAJ model and the transferred model parameters can capture the main features of the hydrological processes in both uncalibrated catchments (western catchments and the entire watershed). This transferability of the model is useful for a scarce data region to simulate the hydrological process and its forecasting.
18 Dissanayake, J.; Han, M. 2021. The effect of number of tanks on water quality in rainwater harvesting systems under sudden contaminant input. Science of the Total Environment, 769:144553. [doi: https://doi.org/10.1016/j.scitotenv.2020.144553]
Rainwater harvesting ; Water quality ; Storage tanks ; Pollutants ; Particulate matter ; Experimentation ; Drinking water ; Developing countries
(Location: IWMI HQ Call no: e-copy only Record No: H050533)
https://www.sciencedirect.com/science/article/pii/S0048969720380840/pdfft?md5=122187d4541e9fe35480b2f1b876453a&pid=1-s2.0-S0048969720380840-main.pdf
https://vlibrary.iwmi.org/pdf/H050533.pdf
https://vlibrary.iwmi.org/pdf/H050533.pdf
(0.97 MB) (992 KB)
Rainwater harvesting (RWH) is a sustainable solution for curbing existing urban water crises. Many countries have implemented various design guidelines for RWH systems, but water quality issues persist, especially with respect to particulate matter and soluble contaminants entering the RWH system after a prolonged dry period. A first-flush unit in an RWH system can partially manage this sudden influx of pollutants, provided that rainfall conditions are favorable for its optimal operation. Therefore, a significant proportion of these pollutants reach the storage tank. The most common single storage tank RWH systems accumulate particulate matter, and allow soluble and particulate contaminants to reach the outlet quickly at undesirably high concentrations. To overcome these issues pertaining to single tank systems, multiple tank systems with similar volumes have been implemented globally. However, limited research has been conducted to assess the effect of the number of tanks on harvested water quality under a sudden pollutant input. Hence, the authors have investigated the effect of the number of tanks on particulate matter distribution in multi-tank systems, and observed that more than 60% of the particle mass input was retained in the first tank. By increasing the number of tanks, the particle mass reaching the final tank becomes constant despite changes in the flowrate and influx particle mass. Furthermore, a soluble contaminant entering a multi-tank system was observed to reside within the system for a prolonged time by approximately a factor of two, which is favorable for developing a response strategy. It is recommended by the authors that at least three tanks should be used to gain the benefits of a multiple-tank RWH system.
19 Amirova, I.; Petrick, M.; Djanibekov, N. 2022. Investment traps and resilience to shocks: an experimental study of Central Asian collective water governance. Irrigation and Drainage, 14p. (Online first) [doi: https://doi.org/10.1002/ird.2704]
Water governance ; Collective action ; Water management ; Resilience ; Investment ; Water users ; Farmers ; Irrigation systems ; Infrastructure ; Monitoring ; Experimentation ; Institutions ; Models / Central Asia / Kazakhstan / Uzbekistan
(Location: IWMI HQ Call no: e-copy only Record No: H051013)
(2.16 MB) (2.16 MB)
We theoretically and empirically investigate the investments of water users in a stylized local irrigation system. We model irrigation self-management as an interdependent interaction of users in an evolutionary game and study the resilience of the irrigation system. The theoretical model implies multiple stable equilibria at different efficiency levels. Users may be trapped in a low level of collective investment or succeed by being locked in a high collective investment level, implying an irrigation system resilient against external shocks. The study seeks to empirically identify such lock-ins in experimental interactions among Central Asian farmers. Furthermore, we inquire into whether a pre-play cheap talk opportunity with peer-monitoring or sanctioning treatments influence the self-reinforcing dynamic. Our findings revealed several stable states. Among these states, there are both low and high levels of efficiency, which we measure in the size of public good. Communication among users results in higher collective investment levels. However, this does not guarantee the complete elimination of inferior conventions from best-response play. Penalties crowded out the intrinsic motivation to cooperate as they reduced collective investment in both low- and high-level equilibria. Our findings imply that institutional settings tailored to each community can improve resilience to climate-driven perturbations in water resources.
20 Sahya, A.; Sonkamble, S.; Jampani, Mahesh; Rao, A. N.; Amerasinghe, Priyanie. 2023. Field site soil aquifer treatment shows enhanced wastewater quality: evidence from vadose zone hydro-geophysical observations. Journal of Environmental Management, 345:118749. [doi: https://doi.org/10.1016/j.jenvman.2023.118749]
Wastewater treatment ; Nature-based solutions ; Water quality ; Parameters ; Experimentation ; Soil moisture ; Aquifers ; Groundwater ; Wastewater irrigation ; Periurban areas ; River basins ; Hydrogeology ; Pollutants / India / Hyderabad / Musi River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H052159)
(14.20 MB)
Soil aquifer treatment (SAT) is an emerging, nature-based, economically viable wastewater treatment solution. Currently, most SAT experiments are done at the laboratory scale, which cannot generate the same conditions as natural field sites and limits the understanding of treatment efficiency. The current study carried out in situ SAT experiments in the Musi River basin in India, where wastewater irrigation is a common practice. SAT efficiency was determined using an integrated approach, including electrical resistivity tomography (ERT) surveys, soil investigations (grain size, permeability, and moisture measurements), and biochemical characterization of raw and SAT treated wastewater. The ERT scans of SAT column show lower order electrical resistivity 10-30 O-m with enhanced chargeability >5–6 mV/V attributed to the vadose zone, characterized by clay-rich soil and sandy soil up to 5–6 m depth. The increase in sand percentage (>70%) below 140–160 cm depth corroborates with the high moisture content (23.5%). The vadose zone permeability (K) 1.58 m/day and discharge (Q) 38.19 m3/day is used to determine the pollutants reduction efficiency of SAT column. Hydrogeological and biogeochemical observations reveal that the improved dissolved oxygen from <1.0 to 5–6 mg/L in the vadose zone catalyzes the oxidation of organic matter resulting in the reduction of BOD and COD up to 92% and 97%, respectively, and denitrification reducing NO3-- (0.55 kg/day). In addition, the precipitation and adsorption by kaolinite clay prompted the reduction of PO42- (0.26 kg/day). Furthermore, the oxic-vadose zone could not support the growth of coliforms and faecal coliforms, and the reduction observed was up to 99.99% in the SAT production well. Overall, the results indicated a positive outcome with SAT efficiency and framed the SAT sitting criteria for different geological environments.
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