Soil salinity can arise eventually whenever irrigation occurs since almost all water consists of ... more Soil salinity can arise eventually whenever irrigation occurs since almost all water consists of some dissolved salts, making drainage crucial to leach salts out of the plant root zone. The development of salination can be hastened in the cases of irrigation with low quality water, especially in and and semiarid regions. This research was conducted with the aim of determining the spatial and short time variability of the electrical conductivity (EC) together with soil organic matter (OM) and pH in spruce (Picea pungens) nursery garden soils. The site was not tilled for seven years and irrigated with low quality water for a full growth period after it opened to the nursery. A good understanding of short time variability in soil salinity development in the site would help evaluate the problem and take measures promptly if necessary, for producing high quality seedlings. A total of 396 disturbed soil samples were taken with regular intervals of 5 x 5 in and represented the depth of 0-3...
The effects of wind‐driven rain (WDR) on sand detachment were studied under various raindrop obli... more The effects of wind‐driven rain (WDR) on sand detachment were studied under various raindrop obliquities. Results suggested a significant reduction in compressive stress on sand surfaces for a two‐dimensional experimental set‐up in a wind tunnel. During experiments, sand particles in splash cups were exposed to both wind‐free rain (WFR) and WDR driven by horizontal winds of 6.4, 8.9 and 12.8 m s−1 and rainfall intensities of 50, 60, 75 and 90‐mm h−1 to assess the sand detachment rate (D, in g m−2 s−1). The effects of sand moisture state (dry and wet) on the detachment of different‐sized particles (0.20–0.50 and 0.50–2.00 mm, respectively) were also tested. Factorial analysis of variance showed that shear and compressive stress components evaluated by horizontal and vertical kinetic energy flux terms (KEx and KEy, respectively, in J m−2 s−1) along with their vector sum (KEr, in J m−2 s−1) explained the variation in D. Neither sand size nor sand moisture was statistically significant alone although binary interactions of KEr, KEx and KEy with the sand size and three‐way interaction of KEx, sand size and moisture were statistically significant. These results can be explained by size‐dependent variation in sand compressibility and surface friction related to the total stress field developed by a given partition of shear and compressive stresses of wind‐driven oblique raindrops (KEx/KEy). Further analysis of the variation of the unit sand detachment rate (Du = D/KEr = g J−1) with rain inclination (α, in degrees) better revealed the effect of WDR obliquity on Du that further changed with sand size class and moisture state. Finally, the difference in the resulting stress field differentiable by the oblique raindrop trajectories of the experiment over sand surface significantly affected the non‐cohesive particle detachment rates, to some extent interacted with size‐dependent compressibility and interface shear strength of sand grains.
Soil aggregate stability as a measure of the resistance of the soil structure against to the dest... more Soil aggregate stability as a measure of the resistance of the soil structure against to the destructive effects is closely associated with the soil degradation, and particularly soil susceptibility to detachment and transport subprocesses of erosion is generally controlled by aggregate breakdown mechanism. In this study we aimed to simulate splash and surface erosion processes in laboratory conditions in terms of aggregate size distributions of three different land uses (agricultural area, grassland and forest) and slope degrees (%9, 15 and 20), and two rainfall intensities (80 and 120 mm h) under saturated soil conditions by a rainfall simulator. The soil samples were taken from a semi arid catchment, located in Ankara, Turkey. Soil aggregate breakdown was evaluated by the mean weight diameter values (MWD, mm) of the collected splash and runoff sediments. The results indicated that aggregate size distributions obtained from the splash and runoff sediments were mostly changed with ...
Peer-reviewed research literature on soil-erosion modelling was reviewed. • 66 soil-erosion scien... more Peer-reviewed research literature on soil-erosion modelling was reviewed. • 66 soil-erosion scientists from 25 countries contributed to this study. • Overall, 8471 articles identified as potentially relevant were reviewed. • 1697 articles were reviewed in a comprehensive manner extracting 42 attributes. • A free and open-source database was created.
Wind erosion and resultant dust emissions create significant risks for land degradation and ecosy... more Wind erosion and resultant dust emissions create significant risks for land degradation and ecosystem health in arid and semi-arid regions. In these regions, fallowing constitutes a major component of conventional agriculture. The present study was conducted to determine wind erosion quantities and agricultural activity-induced mass transport from fallow lands and to assess the correlations of mass transport with climate and soil characteristics. Experiments were conducted over the fallow lands of two adjacent agricultural enterprises (Altinova and Gözlü, Turkey). Sediment flux was measured with passive traps in wet and dry seasons (Q<sub>t</sub>WET and Q<sub>t</sub>DRY). Mass transport in wet and dry seasons was respectively measured as 11.38 and 11.40 kg/ha in Altinova and as 31.61 and 19.71 kg/ha in Gözlü. Both the differences between mass transport of the enterprises and the differences between Q<sub>t</sub>WET and Q<sub>t</sub>DRY...
, A series of tests to evaluate the effect of wind on drop size distribution and impact energy we... more , A series of tests to evaluate the effect of wind on drop size distribution and impact energy were carried out in a wind tunnel with rainfall simulation facility. Horizontal wind speed of 5.7, 10.0, and 12,1 m s -1 was applied with high intensity rainfall (97.2 - 143.0 mm h -1 ) with different raindrop size distributions created by adjusting the nozzle for the operating pressures. The median drop size d 50 ranged from 1.00 to 1.63 mm. Drop size distribution changed with wind. The median drop diameter was becoming larger in wind-driven rain compared to windless rain. Wind accompanying rainfall increased the amount of sand splash from splash cups which indicated higher kinetic energy, especially with winds higher than 10.0 m s -1 . Differences in kinetic energy levels between wind-driven and windless rain are ascribed to the higher impact velocity resulting from the vectorial sum of the applied horizontal wind speed and the initial drop velocity created by the spray nozzle, rather than to the change in drop size.
The spatial distribution of the Atterberg limits can be used to distinguish the consistency and b... more The spatial distribution of the Atterberg limits can be used to distinguish the consistency and behaviour of a soil and its engineering properties, which strongly depends on the water content of the soil and types of silts and clays in the soil. By spatial modeling, and comparing the results of ordinary kriging with the cokriging approach, this study aims to find correlations between the Atterberg limits and the selected physical soil parameters in order to examine how effective they are in generating an understanding of the dynamics of a physical soil system.In 156 soil samples, the Atterberg limits and soil moisture conditions were determined, and auxiliary functions were selected by application of cokriging using correlation analysis and regression equations obtained by the residual maximum likelihood (REML). These techniques were evaluated by the results of the mean absolute error (MAE) and the mean squared error (MSE). Cokriging analysis was found to be more effective at estima...
The concept of “Ecosystem Services (ES)” has gained global importance since the 1990s. Today its ... more The concept of “Ecosystem Services (ES)” has gained global importance since the 1990s. Today its link to sustainable development and human welfare is well documented. However, the level of know-how and the scale and effectiveness of practices differ significantly around the globe. The Ecosystem Services Partnership (ESP) National Network of Turkey aims to fill gaps in ES research and foster collaboration among experts in the public and academic sectors and non-governmental organizations. Therefore, a comprehensive review of ES studies was carried out with rigorous literature research. The review of 247 publications showed that ES research has advanced in the last two decades principally as a result of academia&#39;s impetus but increasing efforts in the science-policy interface have also supported its integration into diverse policy sectors. Among all ES, regulating ES were studied more intensely due to the growing effects of climate change on leading economic sectors such as agriculture, forestry, and water management. Monetary valuation and trade-off knowledge have remained low, based on the difficulties in data availability and assessment methods. Although protected areas are critical to biodiversity conservation, the ES concept has not been integrated into protected area management. Therefore, the ES knowledge in Turkey needs to be scaled up to cover the national level, with higher stakeholder engagement and more focused implementation driven by political will.
Recent studies have shown that the vector physics of wind-driven rain (WDR) varies with the angle... more Recent studies have shown that the vector physics of wind-driven rain (WDR) varies with the angle of rain incidence, and especially under high rain inclinations, the slope aspect makes significant differences in the vectoral partitioning of the total rain energy flux. Since such interrill erosion processes of WDR as soil detachment by raindrop impact and particle transport by raindrop-impacted thin flow transport require a component-wise evaluation of fall vectors of both rainfall intensity and raindrop impact velocity, knowing energy flux distribution over a soil surface with a given slope gradient and aspect play a key role to model the sub-processes physically. In this study, vectoral distribution of kinetic energy flux of the wind-driven rains with different slope gradients and aspects were measured using two-dimensional experimental setups at the wind and rain simulation facility of the International Center for Eremology (ICE) in Ghent University in Belgium. Varying fall incide...
Field measurement of wind erosion is still a great challenge for researchers. In this study, fiel... more Field measurement of wind erosion is still a great challenge for researchers. In this study, field performance of a newly designed sediment trap BEST (Basaran and Erpul Sediment Trap) was evaluated for the first time and compared with the commonly used Modified Wilson and Cook (MWAC) traps. Experiments were carried out at the Karapinar Research Station of Konya Soil and Water Resources Institute over the 50 × 50 m tilled sandy loam plot. Three wind erosion events occurred during the experiments. A small amount of sediment was trapped by the MWAC traps only at 0.20 m in all three events, and there were not sufficient sediment measurements at the catch heights to obtain vertical mass flux profiles. On the other hand, BEST was able to catch sufficient amount of sediment at each trap height to calculate soil losses from the experimental fields. Besides, an analysis for particle size characteristics by electron microscopy imagery indicated that almost all of the sediment particles trappe...
Hydraulic properties of soils and soil erodibility are expected to vary after rainfall because of... more Hydraulic properties of soils and soil erodibility are expected to vary after rainfall because of the impact energy of raindrops. Resistance both to rainfall detachment and to runoff detachment might differ after rainfall, and temporal changes in soil erodibility take place. The main objective of this study was to evaluate the effects of subsequent rainfalls (namely the 2nd rainfall) on runoff and erosion, especially sheet and splash erosion. Forty rainfall events in laboratory condition were conducted on Kule clay loam and Musaa¤ili silt loam. Two consecutive rainfalls at an intensity of 60 mm h-1 were applied to soil trays at a slope of 30%, and soil surface was allowed to dry between events. Statistical analyses showed the main effects of rainfall sequence and soil type, as well as their interaction significantly changed the runoff, percolation, runoff sediment, and splash amounts from two soils. The runoff sediment was higher in the subsequent rainfall than those of the 1st rain...
Soil salinity can arise eventually whenever irrigation occurs since almost all water consists of ... more Soil salinity can arise eventually whenever irrigation occurs since almost all water consists of some dissolved salts, making drainage crucial to leach salts out of the plant root zone. The development of salination can be hastened in the cases of irrigation with low quality water, especially in and and semiarid regions. This research was conducted with the aim of determining the spatial and short time variability of the electrical conductivity (EC) together with soil organic matter (OM) and pH in spruce (Picea pungens) nursery garden soils. The site was not tilled for seven years and irrigated with low quality water for a full growth period after it opened to the nursery. A good understanding of short time variability in soil salinity development in the site would help evaluate the problem and take measures promptly if necessary, for producing high quality seedlings. A total of 396 disturbed soil samples were taken with regular intervals of 5 x 5 in and represented the depth of 0-3...
The effects of wind‐driven rain (WDR) on sand detachment were studied under various raindrop obli... more The effects of wind‐driven rain (WDR) on sand detachment were studied under various raindrop obliquities. Results suggested a significant reduction in compressive stress on sand surfaces for a two‐dimensional experimental set‐up in a wind tunnel. During experiments, sand particles in splash cups were exposed to both wind‐free rain (WFR) and WDR driven by horizontal winds of 6.4, 8.9 and 12.8 m s−1 and rainfall intensities of 50, 60, 75 and 90‐mm h−1 to assess the sand detachment rate (D, in g m−2 s−1). The effects of sand moisture state (dry and wet) on the detachment of different‐sized particles (0.20–0.50 and 0.50–2.00 mm, respectively) were also tested. Factorial analysis of variance showed that shear and compressive stress components evaluated by horizontal and vertical kinetic energy flux terms (KEx and KEy, respectively, in J m−2 s−1) along with their vector sum (KEr, in J m−2 s−1) explained the variation in D. Neither sand size nor sand moisture was statistically significant alone although binary interactions of KEr, KEx and KEy with the sand size and three‐way interaction of KEx, sand size and moisture were statistically significant. These results can be explained by size‐dependent variation in sand compressibility and surface friction related to the total stress field developed by a given partition of shear and compressive stresses of wind‐driven oblique raindrops (KEx/KEy). Further analysis of the variation of the unit sand detachment rate (Du = D/KEr = g J−1) with rain inclination (α, in degrees) better revealed the effect of WDR obliquity on Du that further changed with sand size class and moisture state. Finally, the difference in the resulting stress field differentiable by the oblique raindrop trajectories of the experiment over sand surface significantly affected the non‐cohesive particle detachment rates, to some extent interacted with size‐dependent compressibility and interface shear strength of sand grains.
Soil aggregate stability as a measure of the resistance of the soil structure against to the dest... more Soil aggregate stability as a measure of the resistance of the soil structure against to the destructive effects is closely associated with the soil degradation, and particularly soil susceptibility to detachment and transport subprocesses of erosion is generally controlled by aggregate breakdown mechanism. In this study we aimed to simulate splash and surface erosion processes in laboratory conditions in terms of aggregate size distributions of three different land uses (agricultural area, grassland and forest) and slope degrees (%9, 15 and 20), and two rainfall intensities (80 and 120 mm h) under saturated soil conditions by a rainfall simulator. The soil samples were taken from a semi arid catchment, located in Ankara, Turkey. Soil aggregate breakdown was evaluated by the mean weight diameter values (MWD, mm) of the collected splash and runoff sediments. The results indicated that aggregate size distributions obtained from the splash and runoff sediments were mostly changed with ...
Peer-reviewed research literature on soil-erosion modelling was reviewed. • 66 soil-erosion scien... more Peer-reviewed research literature on soil-erosion modelling was reviewed. • 66 soil-erosion scientists from 25 countries contributed to this study. • Overall, 8471 articles identified as potentially relevant were reviewed. • 1697 articles were reviewed in a comprehensive manner extracting 42 attributes. • A free and open-source database was created.
Wind erosion and resultant dust emissions create significant risks for land degradation and ecosy... more Wind erosion and resultant dust emissions create significant risks for land degradation and ecosystem health in arid and semi-arid regions. In these regions, fallowing constitutes a major component of conventional agriculture. The present study was conducted to determine wind erosion quantities and agricultural activity-induced mass transport from fallow lands and to assess the correlations of mass transport with climate and soil characteristics. Experiments were conducted over the fallow lands of two adjacent agricultural enterprises (Altinova and Gözlü, Turkey). Sediment flux was measured with passive traps in wet and dry seasons (Q<sub>t</sub>WET and Q<sub>t</sub>DRY). Mass transport in wet and dry seasons was respectively measured as 11.38 and 11.40 kg/ha in Altinova and as 31.61 and 19.71 kg/ha in Gözlü. Both the differences between mass transport of the enterprises and the differences between Q<sub>t</sub>WET and Q<sub>t</sub>DRY...
, A series of tests to evaluate the effect of wind on drop size distribution and impact energy we... more , A series of tests to evaluate the effect of wind on drop size distribution and impact energy were carried out in a wind tunnel with rainfall simulation facility. Horizontal wind speed of 5.7, 10.0, and 12,1 m s -1 was applied with high intensity rainfall (97.2 - 143.0 mm h -1 ) with different raindrop size distributions created by adjusting the nozzle for the operating pressures. The median drop size d 50 ranged from 1.00 to 1.63 mm. Drop size distribution changed with wind. The median drop diameter was becoming larger in wind-driven rain compared to windless rain. Wind accompanying rainfall increased the amount of sand splash from splash cups which indicated higher kinetic energy, especially with winds higher than 10.0 m s -1 . Differences in kinetic energy levels between wind-driven and windless rain are ascribed to the higher impact velocity resulting from the vectorial sum of the applied horizontal wind speed and the initial drop velocity created by the spray nozzle, rather than to the change in drop size.
The spatial distribution of the Atterberg limits can be used to distinguish the consistency and b... more The spatial distribution of the Atterberg limits can be used to distinguish the consistency and behaviour of a soil and its engineering properties, which strongly depends on the water content of the soil and types of silts and clays in the soil. By spatial modeling, and comparing the results of ordinary kriging with the cokriging approach, this study aims to find correlations between the Atterberg limits and the selected physical soil parameters in order to examine how effective they are in generating an understanding of the dynamics of a physical soil system.In 156 soil samples, the Atterberg limits and soil moisture conditions were determined, and auxiliary functions were selected by application of cokriging using correlation analysis and regression equations obtained by the residual maximum likelihood (REML). These techniques were evaluated by the results of the mean absolute error (MAE) and the mean squared error (MSE). Cokriging analysis was found to be more effective at estima...
The concept of “Ecosystem Services (ES)” has gained global importance since the 1990s. Today its ... more The concept of “Ecosystem Services (ES)” has gained global importance since the 1990s. Today its link to sustainable development and human welfare is well documented. However, the level of know-how and the scale and effectiveness of practices differ significantly around the globe. The Ecosystem Services Partnership (ESP) National Network of Turkey aims to fill gaps in ES research and foster collaboration among experts in the public and academic sectors and non-governmental organizations. Therefore, a comprehensive review of ES studies was carried out with rigorous literature research. The review of 247 publications showed that ES research has advanced in the last two decades principally as a result of academia&#39;s impetus but increasing efforts in the science-policy interface have also supported its integration into diverse policy sectors. Among all ES, regulating ES were studied more intensely due to the growing effects of climate change on leading economic sectors such as agriculture, forestry, and water management. Monetary valuation and trade-off knowledge have remained low, based on the difficulties in data availability and assessment methods. Although protected areas are critical to biodiversity conservation, the ES concept has not been integrated into protected area management. Therefore, the ES knowledge in Turkey needs to be scaled up to cover the national level, with higher stakeholder engagement and more focused implementation driven by political will.
Recent studies have shown that the vector physics of wind-driven rain (WDR) varies with the angle... more Recent studies have shown that the vector physics of wind-driven rain (WDR) varies with the angle of rain incidence, and especially under high rain inclinations, the slope aspect makes significant differences in the vectoral partitioning of the total rain energy flux. Since such interrill erosion processes of WDR as soil detachment by raindrop impact and particle transport by raindrop-impacted thin flow transport require a component-wise evaluation of fall vectors of both rainfall intensity and raindrop impact velocity, knowing energy flux distribution over a soil surface with a given slope gradient and aspect play a key role to model the sub-processes physically. In this study, vectoral distribution of kinetic energy flux of the wind-driven rains with different slope gradients and aspects were measured using two-dimensional experimental setups at the wind and rain simulation facility of the International Center for Eremology (ICE) in Ghent University in Belgium. Varying fall incide...
Field measurement of wind erosion is still a great challenge for researchers. In this study, fiel... more Field measurement of wind erosion is still a great challenge for researchers. In this study, field performance of a newly designed sediment trap BEST (Basaran and Erpul Sediment Trap) was evaluated for the first time and compared with the commonly used Modified Wilson and Cook (MWAC) traps. Experiments were carried out at the Karapinar Research Station of Konya Soil and Water Resources Institute over the 50 × 50 m tilled sandy loam plot. Three wind erosion events occurred during the experiments. A small amount of sediment was trapped by the MWAC traps only at 0.20 m in all three events, and there were not sufficient sediment measurements at the catch heights to obtain vertical mass flux profiles. On the other hand, BEST was able to catch sufficient amount of sediment at each trap height to calculate soil losses from the experimental fields. Besides, an analysis for particle size characteristics by electron microscopy imagery indicated that almost all of the sediment particles trappe...
Hydraulic properties of soils and soil erodibility are expected to vary after rainfall because of... more Hydraulic properties of soils and soil erodibility are expected to vary after rainfall because of the impact energy of raindrops. Resistance both to rainfall detachment and to runoff detachment might differ after rainfall, and temporal changes in soil erodibility take place. The main objective of this study was to evaluate the effects of subsequent rainfalls (namely the 2nd rainfall) on runoff and erosion, especially sheet and splash erosion. Forty rainfall events in laboratory condition were conducted on Kule clay loam and Musaa¤ili silt loam. Two consecutive rainfalls at an intensity of 60 mm h-1 were applied to soil trays at a slope of 30%, and soil surface was allowed to dry between events. Statistical analyses showed the main effects of rainfall sequence and soil type, as well as their interaction significantly changed the runoff, percolation, runoff sediment, and splash amounts from two soils. The runoff sediment was higher in the subsequent rainfall than those of the 1st rain...
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