Kidane Welde, Bogale Gebremariam, Effect of land use land cover dynamics on hydrological response of watershed: Case study of Tekeze Dam watershed, northern Ethiopia, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 1-16, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.03.002.
(http://www.sciencedirect.com/science/article/pii/S2095633916301538)
Abstract: Abstract
Land use change is a very important issue considering global dynamics and their response to hydrologic characteristics of soil and water management in a catchment. A significant land use change has been observed in the Tekeze dam catchment. The main objective of this study was to estimate the potential impacts of the land use land cover (LULC) dynamics on hydrological response (stream flow and sediment yield). This was done by integrating SWAT model with GIS. The simulation and sensitivity analysis for each land use was done by dividing the catchment in to 47 sub-catchments and assigning HRUs based on multiple HRU definition. After a sensitivity analysis, calibration and validation of SWAT model, the impact of LULC dynamics on hydrological response were evaluated with three scenarios (climate of 2000s & 2008 LULC, climate of 2000s & 1986 LULC and climate of 1980s & 1986 LULC). In the Tekeze dam watershed, land cover change had a beneficial impact on modeled watershed response due to the transition from grass and shrub land to agricultural land. Simulation results for the Tekeze dam watershed indicates that increasing bare land and agricultural areas resulted in increased annual and seasonal stream flow and sediment yield in volumes. The mean annual stream flow was increased by 6.02% (129.20–137.74 m3/s) and the impact on sediment yield amounts to an increase of 17.39% (12.54–15.18 t/ha/yr) due to LULC dynamics. The hydrological response was more sensitive to LULC dynamics for the months of August to October than others in the year. These results demonstrate the usefulness of integrating remote sensing and distributed hydrologic models through the use of GIS for assessing watershed conditions and the relative impacts of land cover transitions on hydrologic response in a continuous manner.
Keywords: LULC dynamics; Stream flow; Sediment yield; Tekeze dam; SWAT

Yi Zhang, Mingchang Shi, Xin Zhao, Xiaojing Wang, Zhidong Luo, yuan Zhao, Methods for automatic identification and extraction of terraces from high spatial resolution satellite data (China-GF-1), International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 17-25, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.02.002.
(http://www.sciencedirect.com/science/article/pii/S2095633916301125)
Abstract: Abstract
Terraces are effective measures to control soil and water loss on hillslopes and play significant roles in water storage, soil conservation and increasing of crop yield. With the launch of comprehensive management engineering of transforming slopes into terraces in China, the area of terraces is continuously expanding. To plan for soil and water conservation in a scientific way and ensure rational soil and water conservation measures, it is important to determine a timely and accurate inventory of the spatial distribution of the existing terraces. High-resolution satellite data (China GF-1) was used in this study to automatically identify and extract terraces. The edge characteristics statistics algorithm, template-matching algorithm and the Fourier transformation algorithm were used. The results suggest that the template-matching algorithm, based on high gray features of terraces, has higher identification accuracy and lower extraction miss rate, and is able to determines the complete map spots, which works well for identification and extraction of typical terraces. The Fourier transformation algorithm, based on the texture of the terraces, is easily affected by gray changes on the terrace field surfaces and field ridges and is hardly reliable as a stand-alone technique for terrace identification. In this study, we focused on an area near Hengshan County, Yulin of Shanxi Province, and performed field validation of the terrace automatic identification and extraction algorithms. The results suggest that the accuracy of automatic identification and extraction of the terraces is greater than 80%. The method proposed is helpful to meet the requirements for planning and monitoring soil and water conservation projects.
Keywords: Terraces; Remote sensing; Edge characteristics; Fourier transformation; China-GF-1

Roslan Zainal Abidin, Mohd Sofiyan Sulaiman, Naimah Yusoff, Erosion risk assessment: A case study of the Langat River bank in Malaysia, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 26-35, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.01.002.
(http://www.sciencedirect.com/science/article/pii/S209563391630079X)
Abstract: Abstract
River bank erosion is one of the major and unpredictable hazards worldwide including in Malaysia. Soil detachment at river banks is due to two processes: 1) hydraulic erosion imposed by channel flow and 2) sub aerial erosion due to the weakening and weathering of bank materials. This paper is focused on the second aspect of the erosion process which mainly depends on the combination of rainfall intensity and the ability of the soil to withstand the raindrop effects. The relative combination of sand, silt and clay in a soil is argued to have an impact on erosion resistance. In cohesive soil composition, sand forms the largest size ranging from 0.05 to 2 mm whereas silt is adequately moderate (ranging from 0.002 to 0.05 mm) and clay is the smallest of all three (less than 0.002 mm). With the knowledge that soil composition does indeed have an effect on erosion resistance, this paper will attempt to relate risk assessment index of river bank erosion specifically to soil composition. Thus, the objectives of this document are as follows; 1) to produce risk assessment index for river bank erosion and 2) to carry out a case study for selected rivers in Malaysia pertaining to river bank assessment. The index is produced by inferring the previously developed scale on soil erodibility. Past researchers created the “ROM” scale (named after the researchers, Rolan and Mazidah) to assess degree of soil erodibility into five classes namely “critical”, “very high”, “high”, “medium” and “low”. Instead of using semi empirical formula from the “ROM” scale, a percentage of soil composition was inferred to produce risk assessment index. It was found that as the percentage of clay decreased, susceptibility index became higher and approached a critical level. Application of the newly developed index is verified by conducting a case study at the Langat River, Kajang, Malaysia. The soil composition was classified and form fitted into the index. It was found that the middle reach of the Langat river is susceptible to severe erosion due to low percentage of clay. This finding agreed well with the visual observation of these reaches as a large portion of gully type of erosion had been observed throughout the study. The establishment of risk assessment index which firmly indicates the relationship between soil composition and river bank erosion can be used as a tool in forecasting the risk levels. This formulation is well proven to assess river bank conditions and the associated critical shear stress is very much close with the previously published shear stress.
Keywords: River bank erosion; Percentage occupy; Silt content; Erodibility; Shear stress

Csilla Hudek, Silvia Stanchi, Michele D’Amico, Michele Freppaz, Quantifying the contribution of the root system of alpine vegetation in the soil aggregate stability of moraine, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 36-42, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.02.001.
(http://www.sciencedirect.com/science/article/pii/S2095633916301472)
Abstract: Abstract
One fifth of the world's population is living in mountains or in their surrounding areas. This anthropogenic pressure continues to grow with the increasing number of settlements, especially in areas connected to touristic activities, such as the Italian Alps. The process of soil formation on high mountains is particularly slow and these soils are particularly vulnerable to soil degradation. In alpine regions, extreme meteorological events are increasingly frequent due to climate change, speeding up the process of soil degradation and increasing the number of severe erosion processes, shallow landslides and debris flows. Vegetation cover plays a crucial role in the stabilization of mountain soils thereby reducing the risk of natural hazards effecting downslope areas. Soil aggregate stability is one of the main soil properties that can be linked to soil loss processes. Soils developed on moraines in recently deglaciated areas typically have low levels of soil aggregation, and a limited or discontinuous vegetation cover making them more susceptible to degradation. However, soil structure can be influenced by the root system of the vegetation. Roots are actively involved in the formation of water-stable soil aggregation, increasing the stability of the soil and its nutrient content. In the present study, we aim to quantify the effect of the root system of alpine vegetation on the soil aggregate stability of the forefield of the Lys glacier, in the Aosta Valley (NW-Italy). This proglacial area provides the opportunity to study how the root system of ten pioneer alpine species from different successional stages can contribute to soil development and soil stabilization. To quantify the aggregate stability of root permeated soils, a modified wet sieving method was employed. The root length per soil volume of the different species was also determined and later correlated with the aggregate stability results. The results showed that soil aggregate stability was significantly increased by the presence of roots. The lowest soil aggregate stability was found with Epilobium fleischeri followed by Minuartia recurva and Leucanthemopsis alpina. The highest aggregate stability was found with the graminoid species. These results show a close relationship between the development of root systems of the studied species and soil aggregate stability, a factor which can be taken into consideration in order to improve the accuracy of existing susceptibility mapping for early warning and civilian protection.
Keywords: Soil aggregate stability; Root length density; Pioneer alpine species; Glacier forefield

Masoud Bijani, Ezatollah Ghazani, Naser Valizadeh, Negin Fallah Haghighi, Pro-environmental analysis of farmers' concerns and behaviors towards soil conservation in central district of Sari County, Iran, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 43-49, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.03.001.
(http://www.sciencedirect.com/science/article/pii/S2095633916301514)
Abstract: Abstract
This study aimed to pro-environmentally analyze farmers' concerns and behaviors towards soil conservation. This research was a descriptive, causal, and correlational and conducted through a survey technique. The study population consisted of all farmers at the central district of Sari county, Iran (N=9621). Based on the Cochran's formula, 120 farmers were selected using stratified random sampling. The instrument employed in this study was a questionnaire with its validity being confirmed by a number of academic experts and agriculture specialists and its reliability being proved using Cronbach's alpha coefficients in a pilot study (outside the scope of the current study). (0.66≤α≤0.90). The results of the analysis regarding the effects of independent variables on the variables "soil conservation behavior" and "soil conservation concern" indicated that, among the variables affecting these two variables, the variable "attitude towards soil conservation "was the most powerful predictor of "soil conservation concerns" and the variable "social pressures on soil conservation" predicted farmers' "soil conservation behaviors" better. Furthermore, the independent variables used in this research could predict 42% of the variance in terms of soil conservation concern and 21% of the variance in terms of soil conservation behavior. These findings can be practical and appropriate for executive officials since, instead of making efforts to direct change the behavior, they can first focus on conceptual changes and persuasive changes like changing attitudes towards soil conservation.
Keywords: Soil conservation behavior; Soil conservation concern; Farmers; Sari County

Tijana Vulević, Nada Dragović, Multi-criteria decision analysis for sub-watersheds ranking via the PROMETHEE method, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 50-55, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.01.003.
(http://www.sciencedirect.com/science/article/pii/S2095633916300958)
Abstract: Abstract
Soil and water resources are important elements of the environment that is managed to reduce the erosion rate and the destructive effects of torrential flooding. Implementation of the measures to reach this goal requires the ranking of sub-watersheds and areas within the sub-watersheds, from most to least vulnerable, which can be achieved using Multi-criteria decision analysis methods. In this paper, using the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) II method ranking of nine sub-watersheds delineated in the Topciderska river watershed, Serbia, was performed by using ArcGIS software. The criteria used for determining the order of the most vulnerable sub-watersheds are land cover, rainfall, soil erodibility as well as topography. The importance of criteria was determined by using the Analytic Hierarchy Process (AHP) method, and the influence of the criteria weights on ranking results was tested. This research identified that the most vulnerable sub-watershed is located in the upper part of the study area, where 15% of the territory is at high risk of erosion. Thus, this sub-watershed should have priority for protection through the implementation of appropriate measures and works. The results of the PROMETHEE II method and the ArcGIS application represent the valuable information for watershed management planning and implementation of soil erosion and torrent control measures.
Keywords: Sub-watershed; Soil erosion; Ranking; PROMETHEE method

Desalew Meseret Moges, Aklilu Amsalu Taye, Determinants of farmers’ perception to invest in soil and water conservation technologies in the North-Western Highlands of Ethiopia, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 56-61, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.02.003.
(http://www.sciencedirect.com/science/article/pii/S2095633916300879)
Abstract: Abstract
Soil erosion by water is a severe and continuous ecological problem in the north-western Highlands of Ethiopia. Limited perception of farmers to practice soil and water conservation (SWC) technologies is one of the major causes that have resulted accelerated soil erosion. Therefore, this paper examines the major determinants of farmers’ perception to use and invest in SWC technologies in Ankasha District, north-western highlands of Ethiopia. A detailed field survey was carried out among 338 households, randomly selected from two rural sample kebeles (called villages here after). Descriptive statistics and logistic regression model were used to analyse the effects of multiple variables on farmers’ perception. The results indicate that educational level of the respondents and their access to trainings were found to have a positive and very significant association (P<0.01) with farmers’ perception. Likewise, land ownership, plot size, slope type, and extension contact positively and significantly influenced farmers’ perception at 5% level of significance. On the other hand, the influence of respondents’ age and plot distance from the homestead was found to be negative and significant (P<0.05). The overall results of this study indicate that the perception of farmers to invest in SWC technologies was highly determined by socioeconomic, institutional, attitudinal and biophysical factors. Thus, a better understanding of constrains that influence farmers' perception is very important while designing and implementing SWC technologies. Frequent contacts between farmers and extension agents and continues agricultural trainings are also needed to increase awareness of the impacts of SWC benefits.
Keywords: Soil erosion; Farmers’ perception; Soil and water conservation; Logistic regression; Ethiopia

Shagufta Qasim, Shamim Gul, Maria Hussain Shah, Fayyaz Hussain, Sarfraz Ahmad, Muhammad Islam, Gulbano Rehman, Muhammad Yaqoob, Syed Qasim Shah, Influence of grazing exclosure on vegetation biomass and soil quality, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 62-68, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.01.004.
(http://www.sciencedirect.com/science/article/pii/S2095633916301411)
Abstract: Abstract
This study investigated the influence of sixteen years exclosure from unmanaged grazing on aboveground vegetation biomass, soil organic matter (SOM), soil aggregation and nitrogen (N) mineralization in arid shrubland of Baluchistan, Pakistan. Sampling was carried out from three sites along the chronosequence of secondary succession. One site was located at open-for-grazing area (grazed site) and the other two sites were located in the area that is protected since 1998. One of the protected site is more remote from grazing (protected site 1) where the land is less disturbed and has thick vegetation than the other protected site (protected site 2). Results showed a significant difference for aboveground vegetation biomass across sites and was in the order of protected site 1> protected site 2> grazed site. Soil organic matter was 53% and 46% higher in protected sites than grazed site. Aggregates larger than 2 mm size were not detected in soil from grazed site but represented 4.5% and 3% of the sample soil profile at the protected site 1 and protected site 2, respectively. Rate of N mineralization was lower in soils at the grazed site as compared to soils at the protected sites. Soil moisture contents were significantly lower at grazed site and showed a strong positive correlation with aboveground vegetation biomass. This study demonstrates that unmanaged grazing severely affected aboveground vegetation biomass, soil organic matter, large-sized soil aggregates, nitrogen mineralization and soil moisture contents. Short term exclosure from grazing (~16 years) can enhance aboveground vegetation biomass and soil quality in terms of soil organic matter accumulation, soil aggregation, retention of soil moisture and nitrogen mineralization in this arid rangeland.
Keywords: Rangeland; Grazing; Soil organic matter; Aggregation; Nitrogen mineralization

Miguel Oliveras-Berrocales, David Sotomayor-Ramírez, Jorge A. Delgado, Luis R. Pérez-Alegría, The new Caribbean Nitrogen Index to assess nitrogen dynamics in vegetable production systems in southwestern Puerto Rico, International Soil and Water Conservation Research, Volume 5, Issue 1, March 2017, Pages 69-75, ISSN 2095-6339, http://dx.doi.org/10.1016/j.iswcr.2017.01.001.
(http://www.sciencedirect.com/science/article/pii/S2095633916301575)
Abstract: Abstract
Nutrient loss from agricultural fields is one of the main factors influencing surface- and ground-water quality. Typical fertilizer nitrogen (N) consumption rates in vegetable production systems and horticultural crops in Puerto Rico fluctuate between 112 and 253 kg N/ha. The nitrogen use efficiency of vegetable crops is low, increasing the potential for nitrogen losses and high residual soil nitrate content. Quantification of residual soil N and N losses to the environment can be a difficult task. Simulation models such as the USDA-ARS N Index can be used to identify the relative magnitude of varying N-loss pathways and to identify best management practices. Field studies were conducted to quantify residual soil N and crop N removal, and to validate the Nitrogen Index in onion, tropical pumpkin and tomato production systems in the Lajas Valley in southwestern Puerto Rico. Relationships between observed and simulated values were determined to examine the capability of the model for evaluating N losses. There was good correlation between observed and predicted values for residual soil N (r =0.88) and crop N removal (r =0.99) (p<0.05). In the production systems evaluated, the N volatilization losses ranged from 1 to 4 kg N/ha, the denitrification losses ranged from 18 to 46 kg N/ha, the leaching losses ranged from 155 to 779 kg N/ha, and the residual soil nitrate ranged from 64 to 401 kg N/ha. The N use efficiency ranged from 15% to 39%. The results obtained showed that the Nitrogen Index tool can be a useful tool for evaluating N transformations in vegetable production systems of Puerto Rico's semi-arid zone.
Keywords: Nitrogen index; Nitrogen management; Residual soil N; Crop N removal