International Soil and Water Conservation Research
Volume 4, Issue 3, Pages 151-236(Sep. 2016)
Independent principal component analysis for simulation of soil water content and bulk density in a Canadian Watershed
Pages 151-158
Alaba Boluwade, Chandra A. Madramootoo
Soil erodibility mapping using three approaches in the Tangiers province –Northern Morocco
Pages 159-167
Hamza Iaaich, Rachid Moussadek, Bouamar Baghdad, Rachid Mrabet, Ahmed Douaik, Derradji Abdelkrim, Abdelhak Bouabdli
Improved USLE-K factor prediction: A case study on water erosion areas in China
Pages 168-176
Bin Wang, Fenli Zheng, Yinghui Guan
Assessing sediment yield in Kalaya gauged watershed (Northern Morocco) using GIS and SWAT model
Pages 177-185
Hamza Briak, Rachid Moussadek, Khadija Aboumaria, Rachid Mrabet
Change in rainfall erosivity in the past and future due to climate change in the central part of India
Pages 186-194
Arun Mondal, Deepak Khare, Sananda Kundu
Farming methods impact on soil and water conservation efficiency under tea [Camellia sinensis (L.)] plantation in Nilgiris of South India
Pages 195-198
Dhruba Charan Sahoo, Made Gowda Madhu, Sivagnanam Santhana Bosu, Om Pal Singh Khola
Assessment of sediment yield using RS and GIS at two sub-basins of Dez Watershed, Iran
Pages 199-206
Hamed Noori, Seyed Mostafa Siadatmousavi, Barat Mojaradi
Predicted and measured soil retention curve parameters in Lombardy region north of Italy
Pages 207-214
Fatma Wassar, Claudio Gandolfi, Michele Rienzner, Enrico Antonio Chiaradia, Ettore Bernardoni
The centrality of water resources to the realization of Sustainable Development Goals (SDG). A review of potentials and constraints on the African continent
Soil respiration responses to soil physiochemical properties in urban different green-lands: A case study in Hefei, China
Pages 224-229
Xiao Tao, Jun Cui, Yunze Dai, Zefu Wang, Xiaoniu Xu
Effects of compost age on the release of nutrients
Pages 230-236
Bilal B. Al-Bataina, Thomas M. Young, Ezio Ranieri
Free full papers and open access are available at
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with free access to the paper abstracts.
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Alaba Boluwade, Chandra A. Madramootoo, Independent principal component analysis for simulation of soil water content and bulk density in a Canadian Watershed, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 151-158, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.09.001.
(http://www.sciencedirect.com/science/article/pii/S2095633916300065)
Abstract: Abstract
Accurate characterization of soil properties such as soil water content (SWC) and bulk density (BD) is vital for hydrologic processes and thus, it is importance to estimate θ (water content) and ρ (soil bulk density) among other soil surface parameters involved in water retention and infiltration, runoff generation and water erosion, etc. The spatial estimation of these soil properties are important in guiding agricultural management decisions. These soil properties vary both in space and time and are correlated. Therefore, it is important to find an efficient and robust technique to simulate spatially correlated variables. Methods such as principal component analysis (PCA) and independent component analysis (ICA) can be used for the joint simulations of spatially correlated variables, but they are not without their flaws. This study applied a variant of PCA called independent principal component analysis (IPCA) that combines the strengths of both PCA and ICA for spatial simulation of SWC and BD using the soil data set from an 11 km2 Castor watershed in southern Quebec, Canada. Diagnostic checks using the histograms and cumulative distribution function (cdf) both raw and back transformed simulations show good agreement. Therefore, the results from this study has potential in characterization of water content variability and bulk density variation for precision agriculture.
Keywords: Spatial variability; Soil properties; Agricultural decision-making; Independent principal component analysis
Hamza Iaaich, Rachid Moussadek, Bouamar Baghdad, Rachid Mrabet, Ahmed Douaik, Derradji Abdelkrim, Abdelhak Bouabdli, Soil erodibility mapping using three approaches in the Tangiers province –Northern Morocco, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 159-167, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.07.001.
(http://www.sciencedirect.com/science/article/pii/S2095633915301052)
Abstract: Abstract
Soil erodibility is a key factor in assessing soil loss rates. In fact, soil loss is the most occurring land degradation form in Morocco, affecting rural and urban vulnerable areas. This work deals with large scale mapping of soil erodibility using three mapping approaches: (i) the CORINE approach developed for Europe by the JRC; (ii) the UNEP/FAO approach developed within the frame of the United Nations Environmental Program for the Mediterranean area; (iii) the Universal Soil Loss Equation (USLE) K factor. Our study zone is the province of Tangiers, North-West of Morocco. For each approach, we mapped and analyzed different erodibility factors in terms of parent material, topography and soil attributes. The thematic maps were then integrated using a Geographic Information System to elaborate a soil erodibility map for each of the three approaches. Finally, the validity of each approach was checked in the field, focusing on highly eroded areas, by confronting the estimated soil erodibility and the erosion state as observed in the field. We used three statistical indicators for validation: overall accuracy, weighted Kappa factor and omission/commission errors. We found that the UNEP/FAO approach, based principally on lithofacies and topography as mapping inputs, is the most adapted for the case of our study zone, followed by the CORINE approach. The USLE K factor underestimated the soil erodibility, especially for highly eroded areas.
Keywords: Erodibility; Soil; Mapping; Tangiers; Morocco
Bin Wang, Fenli Zheng, Yinghui Guan, Improved USLE-K factor prediction: A case study on water erosion areas in China, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 168-176, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.08.003.
(http://www.sciencedirect.com/science/article/pii/S2095633916300648)
Abstract: Abstract
Soil erodibility (K-factor) is an essential factor in soil erosion prediction and conservation practises. The major obstacles to any accurate, large-scale soil erodibility estimation are the lack of necessary data on soil characteristics and the misuse of variable K-factor calculators. In this study, we assessed the performance of available erodibility estimators Universal Soil Loss Equation (USLE), Revised Universal Soil Loss Equation (RUSLE), Erosion Productivity Impact Calculator (EPIC) and the Geometric Mean Diameter based (Dg) model for different geographic regions based on the Chinese soil erodibility database (CSED). Results showed that previous estimators overestimated almost all K-values. Furthermore, only the USLE and Dg approaches could be directly and reliably applicable to black and loess soil regions. Based on the nonlinear best fitting techniques, we improved soil erodibility prediction by combining Dg and soil organic matter (SOM). The NSE, R2 and RE values were 0.94, 0.67 and 9.5% after calibrating the results independently; similar model performance was showed for the validation process. The results obtained via the proposed approach were more accurate that the former K-value predictions. Moreover, those improvements allowed us to effectively establish a regional soil erodibility map (1:250,000 scale) of water erosion areas in China. The mean K-value of Chinese water erosion regions was 0.0321 (t ha h)·(ha MJ mm)−1 with a standard deviation of 0.0107 (t ha h)·(ha MJ mm)−1; K-values present a decreasing trend from North to South in water erosion areas in China. The yield soil erodibility dataset also satisfactorily corresponded to former K-values from different scales (local, regional, and national).
Keywords: Erodibility assessment; Erodibility map; K-value; Modeling; China
Hamza Briak, Rachid Moussadek, Khadija Aboumaria, Rachid Mrabet, Assessing sediment yield in Kalaya gauged watershed (Northern Morocco) using GIS and SWAT model, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 177-185, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.08.002.
(http://www.sciencedirect.com/science/article/pii/S2095633916300211)
Abstract: Abstract
An efficient design for erosion-control structures of any watershed in the world is entrusted with the delicate forecasting of sediment yields. These outlook yields are usually inferred by extrapolations from past observations. Because runoff, as the transporting vehicle, is more closely correlated with sediment yields than any other variable. So, calibration as well as validation of process-based hydrological models are two major processes while estimating the sediment yield in watershed. The actual survey is fulfilled with the aim of developing a trustworthy hydrologic model simulating stream flow discharge and sediment concentration with least uncertainty among the parameters picked out for calibration so as to verify the effect of the scenarios on the spatial distribution of sediment yield (sediments transported from sub-basins to the main channel during the step of time). Soil and Water Assessment Tool (SWAT, version 2012) model integrated with Geographic Information System (GIS, version 10.1) was used to simulate the stream flow and sediment concentration of Kalaya catchment situated in north of Morocco for the period from 1971 to 1993. Model calibration and validation were performed for monthly time periods using Sequential Uncertainty Fitting 2 (SUFI-2, version 2) within SWAT-CUP using 16 parameters. Our calibration outputs for monthly simulation for the period from 1976 to 1984 showed a good model performance for flow rates with NSE and PBIAS values of 0.76 and −11.80, respectively; also a good model performance for sediment concentration with NSE and PBIAS values of 0.69 and 7.12, respectively. Nonetheless, during validation period (1985–1993) for monthly time step, the NSE and PBIAS values were 0.67 and −14.44, respectively for flow rates and these statistical values were 0.70 and 15.51, respectively for sediment concentration; which also means a good model performance for both. Following calibration, the inclusive effect of each parameter used was ranked using global sensitivity function in SWAT-CUP. From our analysis, the effective hydraulic conductivity in main channel alluvium (CH_K2), USLE support practice factor (USLE_P) and manning's "n" value for the main channel (CH_N2) were found to be the most sensitive parameters during different iterations with different number of simulation but with the same inputs. The least sensitive parameter were found to be different in either cases unlike the most sensitive parameters. As a result, the global evaluated soil erosion rate in the study area varied from 20 to 120 t/ha/yr. It was summarized that the entire knowledge of the hydrologic processes happens within the watershed and the consciousness about acceptable meaningful range of the parameters is crucial while developing reliable hydrologic model.
Keywords: Erosion-control; SWAT model; Simulation; Watershed; Northern Morocco
Arun Mondal, Deepak Khare, Sananda Kundu, Change in rainfall erosivity in the past and future due to climate change in the central part of India, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 186-194, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.08.004.
(http://www.sciencedirect.com/science/article/pii/S2095633916300053)
Abstract: Abstract
Temporal change in rainfall erosivity varies due to the rainfall characteristic (amount, intensity, frequency, duration), which affects the conservation of soil and water. This study illustrates the variation of rainfall erosivity due to changing rainfall in the past and the future. The projected rainfall is generated by SDSM (Statistical DownScaling Model) after calibration and validation using two GCMs (general circulation model) data of HadCM3 (A2 and B2 scenario) and CGCM3 (A1B and A2 scenario). The selected study area is mainly a cultivable area with an agricultural based economy. This economy depends on rainfall and is located in a part of the Narmada river basin in central India. Nine rainfall locations are selected that are distributed throughout the study area and surrounding. The results indicate gradually increasing projected rainfall while the past rainfall has shown a declined pattern by Mann–Kendall test with statistical 95% confidence level. Rainfall erosivity has increased due to the projected increase in the future rainfall (2080 s) in comparison to the past. Rainfall erosivity varies from −32.91% to 24.12% in the 2020s, −18.82 to 75.48% in 2050 s and 20.95–202.40% in 2080s. The outputs of this paper can be helpful for the decision makers to manage the soil water conservation in this study area.
Keywords: Rainfall erosivity; Statistical DownScaling Model (SDSM); General circulation model; Narmada river; Mann–Kendall test
Dhruba Charan Sahoo, Made Gowda Madhu, Sivagnanam Santhana Bosu, Om Pal Singh Khola, Farming methods impact on soil and water conservation efficiency under tea [Camellia sinensis (L.)] plantation in Nilgiris of South India, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 195-198, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.07.002.
(http://www.sciencedirect.com/science/article/pii/S2095633915301210)
Abstract: Abstract
Growing of tea on sloping land without any soil and water conservation measures causes enormous soil loss especially in the initial years. For sound soil and water conservation planning, there is a need to evaluate the various conservation measures as related to the amount of expected runoff and soil erosion. In this context, a field study was conducted in the farmer's field in Nilgiris of South India, for evaluating the impact of farming methods on soil and water conservation efficiency under new tea plantation. One year old B-6 tea clones were planted at double hedge spacing (135 cm×75 cm×75 cm) in two slopes (8–12% and 30–35%) with treatments viz., contour staggered trenches (CST), vegetative barrier (VB), CST alternate with VB, CST with cover crop of beans and farmers’ practice of plantation. Minimum runoff (14.6%) was observed from CST with cover crop of beans followed by CST (15.4%) under 8–12% slope range with exactly similar trend in runoff from the plots under 30–35% slope. Contrary to runoff, minimum soil loss was observed from CST (4.9 and 6.9 t ha−1 yr−1) followed by CST with cover crop of beans (5.3 and 7.3 t ha−1 yr−1) under 8–12% and 30–35% respectively. Implementation CST and CST with cover crop of beans are resulted in better soil moisture under both the slope ranges in comparison to remaining measures as well as farmers’ practice of plantation. Therefore, either CST alone or in combination with cover crop of beans are recommended for soil and water conservation under new tea plantation in the hill slopes.
Keywords: Contour staggered trenches; Conservation efficiency; Cover crop; Vegetative barrier
Hamed Noori, Seyed Mostafa Siadatmousavi, Barat Mojaradi, Assessment of sediment yield using RS and GIS at two sub-basins of Dez Watershed, Iran, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 199-206, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.06.001.
(http://www.sciencedirect.com/science/article/pii/S2095633915301039)
Abstract: Abstract
Soil erosion is a serious threat to soil and water resources in semi-arid regions. Modified Pacific South-west Inter Agency Committee (MPSIAC) and Erosion Potential Method (EPM), as two well-known models, have shown their performance in many case studies. The goal of present study is to assess the efficiency of these methods for estimating the sediments yield and erosion intensity within short-term and long-term timeframes over two sub-basins of Dez watershed, west of Iran. The results showed that the study area can be categorized into slight, moderate, high and very high erosion zones. Almost half of the study area is highly susceptible to erosion due to the geological formations and land cover. Moreover, the long-term (i.e. 30 years) sediment yield of 387 and 615 (kton) y−1 estimated by MPSIAC and EPM models demonstrated the superiority of EPM. Compared to the measured value of 612 (kton) y−1, the performance of EPM was astonishing. By splitting the dataset into six periods of five years, the sediment yield was predicted in short-term periods by both aforementioned methods. Such segmentation provides the opportunity to evaluate the impact of extreme flooding events on the models performances. The results showed that both models failed in estimation of sediment load during flood conditions. Nevertheless, the correlation coefficients for estimating the sediment yield were found to be R=0.93 and R=0.85 for EPM and MPSIAC models respectively, for short-term simulations.
Keywords: Soil erosion; GIS; Remote sensing; Modified Pacific South-West Inter Agency Committee method (MPSIAC); Erosion Potential Method (EPM)
Fatma Wassar, Claudio Gandolfi, Michele Rienzner, Enrico Antonio Chiaradia, Ettore Bernardoni, Predicted and measured soil retention curve parameters in Lombardy region north of Italy, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 207-214, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.05.005.
(http://www.sciencedirect.com/science/article/pii/S2095633915301271)
Abstract: Abstract
Water retention characteristics are fundamental input parameters in any modeling study on water flow and solute transport. These properties are difficult to measure and for that reason, we usually need to use direct and indirect methods to determine them. An extensive comparison between measured and estimated results is needed to determine their applicability for a range of different soils. However this study attempts to make a contribution specifically in this connection. These properties were determined in two representative sites located in Landriano field, in Lombardy region, northern Italy. In the laboratory we used the pressure plate apparatus and the tensiometric box. Field soil water retention was determined including measurements of soil water content with SENTEK probes and matric potential with tensiometers. The soil waer retention curves (SWRC) were also settled on with some recently developed pedo-transfert functions (PTFs). Field retention curves were compared against those obtained from PTFs estimations and laboratory measurements. The comparison showed that laboratory measurements were the most accurate. They had the highest ranking for the validation indices (RMSE ranging between 2.4% and 7.7% and bias between 0.1% and 6.4%). The second best technique was the PTF Rosetta (Schaap et al. 2001). They perform only slightly poorer than the laboratory measurements (RMSE ranging between 2.7% and 10% and bias between 0.3% and 7.7%). The lowest prediction accuracy is observed for the Rawls and Brakensiek (1985) PTF (RMSE ranging between 6.3% and 17% and bias between 5% and 10%) which is in contradiction with previous finding (Calzolari et al., 2001), showing that this function is well representing the retention characteristics of the area. Due to time and cost investments of laboratory and field measurements, we conclude that the Rosetta PTF developed by Schaap et al. (2001) appears to be the best to predict the soil moisture retention curve from easily available soil properties in the Lombardy area and further field investigations would be useful to support this finding.
Keywords: Comparison; Laboratory water retention; Field measurements; Curve measurements; Pedo-transfert functions
Frank Mugagga, Benon B. Nabaasa, The centrality of water resources to the realization of Sustainable Development Goals (SDG). A review of potentials and constraints on the African continent, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 215-223, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.05.004.
(http://www.sciencedirect.com/science/article/pii/S2095633916300090)
Abstract: Abstract
Africa is endowed with vast water resources including but not limited to lakes, rivers, swamps and underground aquifers. However, the way of life in Africa does not reflect this kind of wealth owing majorly to degradation and underutilization of these water resources. This review discusses the centrality of water resources in Africa's pursuit of the Sustainable Development Goals (SDGs). Following the Sustainable Development Model, the paper thematically examines and synthesizes the importance and potentials of water resources to Africa's development through exploring their contributions and limitations to the various economic sectors namely; agricultural and livestock production, energy, manufacturing and processing, tourism, health, fisheries, trade and other institutional mechanisms such as payment for ecosystem services (PES), mutual cooperation and economic cooperation. Data were collected by review of online peer-reviewed and grey literature published between the year 2000 and 2015. It is observed that sustainable management of water and sanitation for all (SDG 6) will be central to the attainment of all the other SDGs (particularly SDG 1 (No poverty), 2 (No hunger), 3 (Good health), 14 (life below water) and 15 (life on land)) across Africa. African states should therefore increase their commitment to water conservation and management as this will significantly decide Africa's future development paths.
Keywords: Water resources conservation; Economic drivers; Sustainable development goals; Africa
Xiao Tao, Jun Cui, Yunze Dai, Zefu Wang, Xiaoniu Xu, Soil respiration responses to soil physiochemical properties in urban different green-lands: A case study in Hefei, China, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 224-229, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.08.001.
(http://www.sciencedirect.com/science/article/pii/S2095633916300508)
Abstract: Abstract
Soil respiration (RS) is an important carbon budget in urban ecosystem. In order to better understand the limiting factors affecting urban soil respiration, we measured RS, soil temperature, soil moisture content, soil organic carbon (SOC), nitrogen (N), C/N, dissolved organic carbon (DOC), microbial biomass carbon (MBC), NO3−-N, NH4+-N, P and fine root biomass from twelve sites of four green-land types (campus green-land, park green-land, residential green-land and factory green-land) for two years in built-up areas of Hefei, China. The results showed that average annual RS was significantly lower in the residential green-land (1.35 μmol m−2 s−1) than in the campus (2.64 μmol m−2 s−1) and park (2.51 μmol m−2 s−1) green-lands. RS positively increased with soil temperature at the range of 2.01–31.26 °C, and Q10 values ranged from 1.48 to 1.65 in the four types of green-lands. Soil moisture (18–25%) showed significantly positive correlation with soil respiration (P<0.01). When precipitation occurred frequently in wet summer, soil moisture served as the dominant control on RS variations. RS was positively related with SOC, NO3−-N, P and fine root biomass (diameter <2 mm), while negatively correlated with DOC at 0–10 cm depth. Our results indicate that decreasing RS may be an optional way to increase carbon sequestration potential for urban ecosystem, and this can be achieved by regulating green-land types and applying appropriate soil nutrients maintenance practices.
Keywords: Urban soil; Soil respiration; Green-land type; Soil properties; Environmental factors
Bilal B. Al-Bataina, Thomas M. Young, Ezio Ranieri, Effects of compost age on the release of nutrients, International Soil and Water Conservation Research, Volume 4, Issue 3, September 2016, Pages 230-236, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2016.07.003.
(http://www.sciencedirect.com/science/article/pii/S2095633916300454)
Abstract: Abstract
Composted organic materials are applied to help restore disturbed soils, speed revegetation, and control erosion; these changes are generally beneficial for stormwater quality. Ensuring that nutrient release from compost is adequate for plant needs without degrading stormwater quality is important since composts release nitrogen at variable rates (1–3% of total N/yr) and the leaching process can extend for many years. The aim of this work was to understand the effect of compost age on the extent and rates of nitrogen release by conducting detailed rainfall simulation studies of one compost type at three different ages. Models describing temporal changes in nitrogen release to runoff during a single storm and across multiple storms were developed and applied to the runoff data. Nitrogen content (%) and bulk density of compost increased with the increase in compost age and total nitrogen release decreased with increasing compost age. The three rain simulations (storms) performed on each of the three compost ages show that nitrogen release declined each day of the repeated daily storms. A first-order kinetic model was used to estimate the amount of nitrogen remaining on compost after several storms.
Keywords: Nitrogen; Compost; Modeling; Rain simulation; Leaching; Nutrients