Your search found 12 records
1 Cofie, Olufunke; Pleysier, J. 2004. Ion exchange involving calcium-potasium (Ca-K) and calcium-magnesium (Ca-Mg) in soil and organic matter fractions. Communications in Soil Science and Plant Analysis, 35(17-18):2417-2431.
Ion exchange ; Soil properties ; Soil organic matter ; Clay ; Fractionation ; Calcium ; Magnesium ; Potassium / Nigeria
(Location: IWMI-HQ Call no: IWMI 631.4 G000 COF Record No: H035917)
The chemical characteristics of two soil types, an Alfisol and an Ultisol, were studied in the humid tropical zone of southern Nigeria. The objective was to investigate the contribution of soil organic matter (SOM) to nutrient retention characteristics and identify those SOM pools that contribute most to the ion exchange properties of the soils. Ion exchange studies involving K-Ca and Mg-Ca systems in whole soil, organic fraction (53-250 mm) and clay fraction (<2 mm ) showed a preference for Ca relative to K in the soil and organic fraction. For the clay fraction in Alfisol, the isotherm in K-Ca system suggested a preference for K at low K saturation, but from about 50% K saturation, the isotherm inferred a preference for Ca. However, the overall selectivity at constant temperature and pressure as expressed by Gibb’s free energy change suggested a stronger binding of K than Ca by the fraction.
2 Weerasinghe, P.; Premalal, N. H. R. 2002. Influence of potassium fertilization on growth and yield of embul banana (Musa spp. AAB group) grown in Rhodudalfs under irrigated conditions. Annals of the Sri Lanka Department of Agriculture, 4:109-117.
(Location: IWMI-HQ Call no: P 7639 Record No: H039365)
3 Rajapakshe, I. H.; Najim, M. M. M. 2007. Water and nutrient balance in paddy field irrigated by wastewater during off (Yala) season in Kurunegala, Sri Lanka. Journal of Applied Irrigation Science, 42(1):77-91.
Rice ; Paddy fields ; Water quality ; Nitrogen ; Phosphorus ; Potassium ; Wastewater irrigation ; Irrigation canals ; Water balance / Sri Lanka / Kurunegala
(Location: IWMI HQ Call no: PER Record No: H040449)
4 Rajakaruna, R. M. P.; Nandasena, K. A.; Jayakody, A. N. 2005. Quality of shallow groundwater in an intensively cultivated hilly catena in up country intermediate zone of Sri Lanka. In Galagedara, L. W. (Ed.). Water resources research in Sri Lanka: Symposium Proceedings of the Water Professional’s Day 2005. Peradeniya, Sri Lanka: PGIA. pp.163-178.
Groundwater ; Water quality ; Calcium ; Magnesium ; Nitrogen ; Sodium ; Potassium ; Phosphorus ; Monitoring ; Analysis ; Irrigation water ; Drinking water ; Domestic water ; Wells ; Water pollution ; Fertilizers ; Vegetables ; Cultivation / Sri Lanka / Badulla / Hulankapolla Village
(Location: IWMI HQ Call no: IWMI 631.7 G744 GAL Record No: H040714)
5 Arasalingam, Sutharsiny; Pathmarajah, S.; Mikunthan, T.; Vithanage, M.; Manthrithilake, Herath. 2013. Impact of agricultural activities on groundwater quality and its suitability for drinking in Valikamam area, Jaffna Peninsula. In Sri Lanka Water Partnership (Lanka Jalani); International Water Management Institute (IWMI); Unilever-Pureit. Proceedings of the First Young Water Professionals Symposium, Colombo, Sri Lanka, 22-23 November 2012. Colombo, Sri Lanka: Sri Lanka Water Partnership (Lanka Jalani); Colombo, Sri Lanka: International Water Management Institute (IWMI); Colombo, Sri Lanka: Unilever-Pureit. pp.74-81.
Groundwater resources ; Drinking water ; Water quality ; Agricultural production ; Wells ; Aquifers ; Fluorides ; Nitrates ; Chlorides ; Calcium ; Magnesium ; Carbonates ; Bicarbonates ; Sodium ; Potassium / Sri Lanka / Jaffna Peninsula / Valikamam / Chunnakam aquifer
(Location: IWMI HQ Call no: 333.91 G744 SRI Record No: H046158)
http://lankajalani.org/wp-content/uploads/2015/03/Proceedings-YWPS.pdf
https://vlibrary.iwmi.org/pdf/H046158.pdf
https://vlibrary.iwmi.org/pdf/H046158.pdf
(0.64 MB) (5.26 MB)
6 Chinnasamy, Pennan; Hubbart, J. A. 2015. Stream and shallow groundwater nutrient concentrations in an Ozark forested riparian zone of the central USA. Environmental Earth Sciences, 73(10):6577-6590. [doi: https://doi.org/10.1007/s12665-014-3880-7]
Groundwater ; Surface water ; Stream flow ; Nutrients ; Nitrates ; Phosphorus ; Potassium ; Ammonium ; Hydrology ; Riparian zones ; Case studies / Central USA / Ozark Forest
(Location: IWMI HQ Call no: e-copy only Record No: H046717)
(1.12 MB)
Characterizing spatiotemporal variations in surface water (SW)–shallow groundwater (GW) nutrient concentrations is important to predict stream ecosystem responses to disturbance. Unfortunately, there is a lack of such information from mixed-deciduous semi-karst hydro-geological regions. Nitrate (NO3 -), total phosphorous (P), potassium (K) and ammonium (NH4 +) concentrations were monitored in a case study between an Ozark stream and riparian hardwood forest GW over the 2011 water year in the central USA. Average SW NO3 -, P, K and NH4 + concentrations were 0.53, 0.13, 3.29 and 0.06 mg L-1, respectively. Nine meters from the streambank, average GW NO3 -concentration was 0.01 mg L-1, while P, K and NH4 + concentrations were 0.03, 1.7 and 0.04 mg L-1, respectively. Hyperbolic dilution model results indicated that NO3 - and K exhibited dilution behavior, while NH4 + had a concentration effect and P was hydrologically constant. Observed seasonal NO3 - concentration patterns of winter maxima and summer minima in SW (1.164 and 0.133 mg L-1) and GW (0.019 and 0.011 mg L-1) were supported by previous studies yet exhibited distinct semi-karst characteristics. Results indicate that in addition to relatively low residence time, lower nutrient concentrations in GW (relative to SW) may suggest that shallow GW flow processes are important for vegetation removal and retention of nutrients from streams in semi-karst shallow groundwater systems of the central USA.
7 Smith, C. J.; Oster, J. D.; Sposito, G. 2015. Potassium and magnesium in irrigation water quality assessment. Agricultural Water Management, 157:59-64. (The Jim Oster Special Issue) [doi: https://doi.org/10.1016/j.agwat.2014.09.003]
Irrigation water ; Wastewater irrigation ; Water quality ; Assessment ; Potassium ; Magnesium ; Sodium ; Soil hydraulic properties ; Hydraulic conductivity / USA / Australia / California
(Location: IWMI HQ Call no: e-copy only Record No: H047500)
(0.51 MB)
There is a growing trend of K replacing Na in wastewaters from agricultural industries to reduce the adverse effects of irrigation with these waters on soil hydraulic properties. However, problems with soil physical properties caused by wastewaters with high concentrations of K have been reported in both Australia and California. A review of the literature dating back to the 1930s supports the general conclusion that the relative order of deleterious effect on soil hydraulic properties of the four common cations in soils is Na >K> Mg > Ca. This paper explores the capabilities of the Cation Ratio of Structural Stability (CROSS), a generalized Sodium Adsorption Ratio incorporating all four cations, as an improved irrigation water quality parameter. This new parameter includes a coefficient for K that accounts for its relative deleterious effect as compared with Na and another coefficient for Mg that accounts for its relative beneficial effect as compared with Ca. Based on optimizing CROSS using threshold electrolyte concentration data for a Sodosol from the Riverina Region of Australia, the deleterious effect of K is estimated to be about one-third of that of Na, while the concentration of Mg needs to be about an order of magnitude larger than Ca to have the same beneficial effect.
8 Akoto-Danso, E. K.; Manka'abusi, D.; Steiner, C.; Werner, S.; Haering, V.; Lompo, D. J.-P.; Nyarko, G.; Marschner, B.; Drechsel, Pay; Buerkert, A. 2019. Nutrient flows and balances in intensively managed vegetable production of two West African cities. Journal of Plant Nutrition and Soil Science, 182(2):229-243. [doi: https://doi.org/10.1002/jpln.201800339]
Wastewater irrigation ; Vegetable growing ; Nutrient balance ; Nutrient use efficiency ; Biochar ; Horticulture ; Leaching ; Volatilization ; Nitrogen fertilizers ; Phosphorus ; Potassium ; Soil fertility ; Irrigation water ; Emission ; Crop production / West Africa / Ghana / Burkina Faso / Tamale / Ouagadougou
(Location: IWMI HQ Call no: e-copy only Record No: H049077)
This study reports and analyzes nutrient balances in experimental vegetable production systems of the two West African cities of Tamale (Ghana) and Ouagadougou (Burkina Faso) over a twoyear period comprising thirteen and eleven crops, respectively. Nutrient-use efficiency was also calculated. In Tamale and Ouagadougou, up to 2% (8 and 80 kg N ha–1) of annually applied fertilizer nitrogen were leached. While biochar application or wastewater irrigation on fertilized plots did not influence N leaching in both cities, P and K leaching, as determined with ion-absorbing resin cartridges, were reduced on biochar-amended plots in Tamale. Annual nutrient balances amounted to +362 kg N ha–1, +217 kg P ha–1, and –125 kg K ha–1 in Tamale, while Ouagadougou had balances of up to +692 kg N ha–1, +166 kg P ha–1, and –175 kg K ha–1 y–1. Under farmers’ practice of fertilization, agronomic nutrient-use efficiencies were generally higher in Tamale than in Ouagadougou, but declined in both cities during the last season. This was the result of the higher nutrient inputs in Ouagadougou compared to Tamale and relatively lower outputs. The high N and P surpluses and K deficits call for adjustments in local fertilization practices to enhance nutrient-use efficiency and prevent risks of eutrophication.
9 Qadir, M.; Drechsel, Pay; Cisneros, B. J.; Kim, Y.; Pramanik, A.; Mehta, P.; Olaniyan, O. 2020. Global and regional potential of wastewater as a water, nutrient and energy source. Natural Resources Forum, 44(1):40-51. [doi: https://doi.org/10.1111/1477-8947.12187]
Wastewater treatment ; Recycling ; Resource recovery ; Reuse ; Nutrients ; Energy sources ; Nitrogen ; Phosphorus ; Potassium ; Fertilizers ; Wastewater irrigation ; Energy generation ; Energy recovery ; Forecasting ; Municipal wastewater ; Sustainable Development Goals ; Urban population ; Water stress / Asia / Africa South of Sahara / Middle East / North Africa / Europe / Latin America / Caribbean / North America / Oceania
(Location: IWMI HQ Call no: e-copy only Record No: H049500)
https://onlinelibrary.wiley.com/doi/epdf/10.1111/1477-8947.12187
https://vlibrary.iwmi.org/pdf/H049500.pdf
https://vlibrary.iwmi.org/pdf/H049500.pdf
(1.44 MB)
There is a proactive interest in recovering water, nutrients and energy from waste streams with the increase in municipal wastewater volumes and innovations in resource recovery. Based on the synthesis of wastewater data, this study provides insights into the global and regional “potential” of wastewater as water, nutrient and energy sources while acknowledging the limitations of current resource recovery opportunities and promoting efforts to fast-track highefficiency returns. The study estimates suggest that, currently, 380 billion m3 (m3 = 1,000 L) of wastewater are produced annually across the world which is a volume fivefold the volume of water passing through Niagara Falls annually. Wastewater production globally is expected to increase by 24% by 2030 and 51% by 2050 over the current level. Among major nutrients, 16.6 Tg (Tg = million metric ton) of nitrogen are embedded in wastewater produced worldwide annually; phosphorus stands at 3.0 Tg and potassium at 6.3 Tg. The full nutrient recovery from wastewater would offset 13.4% of the global demand for these nutrients in agriculture. Beyond nutrient recovery and economic gains, there are critical environmental benefits, such as minimizing eutrophication. At the energy front, the energy embedded in wastewater would be enough to provide electricity to 158 million households. These estimates and projections are based on the maximum theoretical amounts of water, nutrients and energy that exist in the reported municipal wastewater produced worldwide annually. Supporting resource recovery from wastewater will need a step-wise approach to address a range of constraints to deliver a high rate of return in direct support of Sustainable Development Goals (SDG) 6, 7 and 12, but also other Goals, including adaptation to climate change and efforts in advancing “netzero” energy processes towards a green economy.
10 Adimassu, Zenebe; Tamene, L.; Degefie, D. T. 2020. The influence of grazing and cultivation on runoff, soil erosion, and soil nutrient export in the central highlands of Ethiopia. Ecological Processes, 9:23. [doi: https://doi.org/10.1186/s13717-020-00230-z]
Grazing lands ; Cultivated land ; Soil fertility ; Nutrients ; Erosion ; Runoff ; Soil loss ; Land degradation ; Sediment ; Total nitrogen ; Phosphorus ; Potassium ; Highlands ; Watersheds ; Tillage ; Rain / Ethiopia / Galesa Watershed
(Location: IWMI HQ Call no: e-copy only Record No: H049738)
https://ecologicalprocesses.springeropen.com/track/pdf/10.1186/s13717-020-00230-z
https://vlibrary.iwmi.org/pdf/H049738.pdf
https://vlibrary.iwmi.org/pdf/H049738.pdf
(1.74 MB) (1.74 MB)
Background: Grazing by livestock and cultivation have been considered as two important causes of soil erosion and nutrient export. However, there has been limited evidence that grazing or cultivation matters to soil erosion and nutrient export in Ethiopia. Hence, this study was conducted in the Galesa watershed in Ethiopia to examine the effects of grazing and cultivation on runoff, soil loss, and nutrient export. Daily values of runoff, soil erosion, and nutrient outflow were measured for three consecutive years following standard procedures. Independent t test was performed to check if the means of runoff, soil loss, and nutrient loss from grazing and cultivated lands were significantly different. Moreover, repeated analysis of variance (ANOVA) was used to test if mean values of runoff, soil loss, and nutrient export varied significantly over the study years.
Results: Although the average annual runoff depth was 7.8% higher in grazing land (GL), soil erosion was significantly lower (39%) in GL as compared to cultivated land (CL). Similarly, sediment and runoff-associated annual losses of total nitrogen (N), available phosphorus (P), exchangeable potassium (K), and organic carbon (OC) were low in the GL treatments. Lowest losses of total N (9.30 kg ha-1 year-1 ), available P (0.83 kg ha-1 year-1 ), and exchangeable K (1.84 kg ha-1 year-1 ) were recorded in GL treatment. Likewise, lowest losses of sediment-associated total N (32.8 kg ha-1 year-1 ), available P (0.39 kg ha-1 year-1 ), exchangeable K (0.23 kg ha-1 year-1 ), and soil organic carbon (630 kg ha-1 year-1 ) were recorded from GL over the 3 years of experimentation.
Conclusion: Our results indicate that cultivation increased soil erosion as compared to grazing. Although there were significant reductions in soil erosion and nutrient export from grazing lands compared with cultivated lands, the absolute losses were still high. This implies the need for grazing land management using appropriate physical and biological erosion control measures to increase productivity and reduce soil erosion as well as nutrient export.
Results: Although the average annual runoff depth was 7.8% higher in grazing land (GL), soil erosion was significantly lower (39%) in GL as compared to cultivated land (CL). Similarly, sediment and runoff-associated annual losses of total nitrogen (N), available phosphorus (P), exchangeable potassium (K), and organic carbon (OC) were low in the GL treatments. Lowest losses of total N (9.30 kg ha-1 year-1 ), available P (0.83 kg ha-1 year-1 ), and exchangeable K (1.84 kg ha-1 year-1 ) were recorded in GL treatment. Likewise, lowest losses of sediment-associated total N (32.8 kg ha-1 year-1 ), available P (0.39 kg ha-1 year-1 ), exchangeable K (0.23 kg ha-1 year-1 ), and soil organic carbon (630 kg ha-1 year-1 ) were recorded from GL over the 3 years of experimentation.
Conclusion: Our results indicate that cultivation increased soil erosion as compared to grazing. Although there were significant reductions in soil erosion and nutrient export from grazing lands compared with cultivated lands, the absolute losses were still high. This implies the need for grazing land management using appropriate physical and biological erosion control measures to increase productivity and reduce soil erosion as well as nutrient export.
11 Mbangi, A.; Nongqwenga, N.; Mabhaudhi, T. 2023. Calibration accuracy of requirement factor and sorption studies for fertilizer recommendation. Agrosystems, Geosciences and Environment, 6(3):e20401. [doi: https://doi.org/10.1002/agg2.20401]
Fertilizer application ; Sorption isotherms ; Phosphorus ; Potassium ; Equilibration ; Plant growth ; Parameters ; Biomass ; Leaf area index ; Crop yield ; Soil solution ; Physicochemical properties ; Cowpeas ; Mustard ; Maize / South Africa
(Location: IWMI HQ Call no: e-copy only Record No: H052103)
https://acsess.onlinelibrary.wiley.com/doi/epdf/10.1002/agg2.20401
https://vlibrary.iwmi.org/pdf/H052103.pdf
https://vlibrary.iwmi.org/pdf/H052103.pdf
(0.20 MB) (209 KB)
The inconsistent and incoherent approaches by fertilizer recommendations to index crop response has prompted the search for alternative approaches. Some of the problems stem from the overlooking of fundamental soil properties that govern the soil solution, which is where plant roots absorb nutrients for growth. A comparison was made between two contrasting equilibration techniques to evaluate their precision in estimating crop response. Sorption isotherms for phosphorus (P) and potassium (K) were compared to requirement factors. Phosphorus sorption isotherms were determined following the batch equilibration technique. Potassium was developed following equilibration with graded K levels. The requirement factors of both P and K were determined following a 6-week incubation with four different levels of fertilization. Cowpea (Vigna unguiculata), mustard (Brassica juncea), and maize (Zea mays) were used as test crops. The growth parameters measured included biomass (g), height (cm), and leaf area index. At harvest, yield (g pot-1) and uptake (mg pot-1) were also recorded. Linear correlation studies were carried out to evaluate the association between treatments and the growth parameters of the tested crops. Results showed no significant difference (p < 0.05) in maize growth parameters between the equilibration methods, despite the sorption isotherms estimating higher levels of P and K. The sorption isotherms for P and K were 1.7 and 9.8 times higher than their respective requirement factors. The crop response, although relatively similar in both methods, was weakly correlated with the sorption-estimated nutrient levels, indicating an overestimation of nutrients. Therefore, the requirement factors were deemed to be a more precise equilibration technique for estimating nutrient levels.
12 Mndzebele, B.; Ncube, B.; Fessehazion, M.; Mabhaudhi, Tafadzwanashe; Modi, A. T. 2023. Assessment of the effects of NPK fertilizer on edible yield and agro-biological parameters in a cowpea–amaranth intercrop. Frontiers in Sustainable Food Systems, 7:1210984. [doi: https://doi.org/10.3389/fsufs.2023.1210984]
NPK fertilizers ; Cowpeas ; Amaranthus ; Intercropping ; Crop yield ; Cropping systems ; Yield losses ; Parameters ; Food security ; Nutrition security ; Biomass ; Nitrogen fertilizers ; Phosphate fertilizers ; Potassium ; Land use / South Africa
(Location: IWMI HQ Call no: e-copy only Record No: H052404)
https://www.frontiersin.org/articles/10.3389/fsufs.2023.1210984/pdf?isPublishedV2=False
https://vlibrary.iwmi.org/pdf/H052404.pdf
https://vlibrary.iwmi.org/pdf/H052404.pdf
(0.49 MB) (497 KB)
Introduction: Estimates indicate that food and nutritional demand in sub-Saharan African nutrient-poor soils will exceed the high population demand. Vegetables such as amaranth and cowpea are key in contributing to food and nutritional security. Fertilizers are used to mitigate low nutrient levels in soils. This study aimed to investigate the yield parameters of cowpea and amaranth vegetables.
Methods: The experiment was designed with a 2 × 4 factorial treatment structure in a completely randomized design, with intercropping and fertilizer level as treatment factors and with four replications.
Results and discussion: The biomass of amaranth and cowpea increased with increased fertilizer application up to the level of 100% nitrogen, phosphorus, and potassium (NPK) fertilizer. A measure of land utilization showed values greater than one. Crop comparison showed that cowpea was more aggressive, had higher actual yield loss, and was highly competitive compared to amaranth. More income could be obtained from intercropping. The research shows the benefits of fertilizer application in improving the biomass of amaranth and cowpea. Overall, the application of NPK fertilizer at levels up to 100%, based on the results of this study, resulted in higher biomass accumulation and improved intercropping indices.
Methods: The experiment was designed with a 2 × 4 factorial treatment structure in a completely randomized design, with intercropping and fertilizer level as treatment factors and with four replications.
Results and discussion: The biomass of amaranth and cowpea increased with increased fertilizer application up to the level of 100% nitrogen, phosphorus, and potassium (NPK) fertilizer. A measure of land utilization showed values greater than one. Crop comparison showed that cowpea was more aggressive, had higher actual yield loss, and was highly competitive compared to amaranth. More income could be obtained from intercropping. The research shows the benefits of fertilizer application in improving the biomass of amaranth and cowpea. Overall, the application of NPK fertilizer at levels up to 100%, based on the results of this study, resulted in higher biomass accumulation and improved intercropping indices.
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