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Knowledge of soil properties such as texture, bulk density, organic matter, soil reaction, soil electrical conductivity, and soil erodibility factor is fundamental to the sustainable management of soil resources. This study aimed to determine the changes in certain soil properties including texture, bulk density, organic matter, pH, electrical conductivity, and soil erodibility factor with different land uses, elevation zones and soil depths in the Arhavi Sub-basin, Artvin, Turkiye. For these purposes, a total of 618 soil samples (309 disturbed and 309 undisturbed) were taken from 155 sampling points located in areas with different land uses, including tea (33 sampling points), hazelnut (33 sampling points), forest (67 sampling points), and grassland (22 sampling points). The results of the statistical analysis revealed that the soils at depths of 0–15 cm and 15–30 cm showed significant differences according to the land use in terms of sand, clay, silt, bulk density, organic matter, and pH. There were significant positive correlations between elevation and soil bulk density (r = 0.495) at a soil depth of 0–15 cm in the tea areas. In the grassland areas, there were significant positive correlations between elevation and silt, bulk density, and the soil erodibility factor (r = 0.485, r = 0.794, and r = 0.442, respectively) at depths of 0–15 cm, and significant positive correlations between elevation and both silt and bulk density (r = 0.468 and r = 0.691, respectively) at depths of 15–30 cm. Similarly, there were significant positive correlations between elevation and both sand and organic matter at soil depths of 0–15 cm and 15–30 cm (sand: r = 0.351 and r = 0.638, respectively; organic matter: r = 0.277 and r = 0.587, respectively). On the other hand, significant negative correlations were found between elevation and silt, bulk density, pH, and the soil erodibility factor at depths of 0–15 cm and 15–30 cm (silt: r = −0.400 and r = −0.461, respectively; bulk density: r = −0.593 and r = −0.545, respectively; pH: r = −0.354 and r = −0.309, respectively; soil erodibility factor: r = −0.443 and r = −520, respectively). Soil acidity was found to be the most important problem threatening soil fertility in all land uses. The use of soil acidity-increasing fertilizers, such as ammonium sulfate, in tea gardens in the region should be eliminated to protect the fertility of soils in the future. The knowledge that this study provides might help farmers and foresters in the region in the proper management and fertilization of their lands. Moreover, this study will provide data to future studies related to soil acidification, soil erosion, and land use that are planned for the Arhavi Sub-basin.

Stream bank erosion in agricultural landscapes is a major pathway for non-point source sediment and phosphorus loading of receiving waters. Previous studies have shown direct and indirect effects of land use on stream bank erosion, and identified high erosion rates within riparian pastures. One potential impact of agricultural land-use on stream bank erosion is the alteration of stream stage characteristics, including an increase in frequency of high-stage events over short periods of time (forming flash hydrographs). The objective of this study was to assess the relationship between the number of high stream stages and corresponding stream bank soil erosion. The study was conducted in six grazed pasture stream reaches within the Rathbun Lake Watershed, a reservoir on the Chariton River located within the Southern Iowa Drift Plain. The erosion pin method was utilized to measure the change in stream bank erosion in response to differences in the number of high stream-stage events, which were monitored by pressure transducers. The measured seasonal bank erosion rates were correlated with the different stream stages data to assess their impact on stream bank erosion. Based on the different model assumptions, there were generally strong linear relationships between high stage and bank erosion. Approximately 75% of the variability in stream bank erosion rates was directly linked to the number of high stages/erosive stream flow depths. Conservation practices that reduce these erosion rates will be those that increase soil-water infiltration, reduce the frequency of high stream flow events and increase bank stability through perennial vegetation cover or reducing disturbance within the riparian zone.

Factors influencing streambank erosion at the field/reach scale include both watershed and riparian land-uses, stream hydrology and channel morphology at the catchment scale. This study assesses the relationship of riparian land-uses, stream morphologic characteristics and catchment scale variables to streambank erosion within grazed riparian pastures in the Southern Iowa Drift Plain. Thirteen cooperating beef cow&ndash, calf farms and their catchments ranging from 2.5 to 12.9 km2 in the Rathbun Lake watershed in South Central Iowa (USA) were chosen to conduct this study. Results suggest that the integration of stream morphologic characteristics and riparian land-uses at both the reach and catchment scale are necessary to explain the current level of streambank erosion measured at the reach scale. Larger catchment size or catchments with more total channel length were found to experience more bank erosion at the reach scale. A significant positive relationship between percent sand-and-silt in the bank soil and bank erosion rates implies that bank soils with less cohesiveness are more erodible. Catchment-scale assessments of the thirteen watersheds showed that within the 50 m corridor on both sides of the stream, 46 to 61% of riparian area was devoted to agricultural use and only 6 to 11% was in ungrazed perennial vegetation, much of it enrolled in the USDA Conservation Reserve Program. Overall, this and previous Rathbun watershed studies have shown that intensive agricultural use of riparian areas over such extents of time and scale could be directly (in field scale) and/or indirectly (watershed scale) related to excessive amounts of streambank erosion (ranging from 8.6 to 38.3 cm/yr) to receiving streams and lakes leading to their impairment and reduction in ecological services. Exclusion of cattle grazing in the riparian areas along buffered stream lengths (2.1% of the total watershed area) of the Rathbun watershed would reduce this impact. This approach could also be applicable to other similar watersheds with extensive land-use under grazed management.

Protected areas are necessary for the conservation and enhancement of biodiversity. Wildfires are major threats to forests and other natural areas, because they may cause irreversible damages. The aim of this study was to analyze the perspective of experts (N = 284), from six countries of the Black Sea, on the current status and problems of protected areas and wildfires. Understanding their points of view could enhance future management on these issues in the region. Data collection was carried out for 9 months, using a web-based questionnaire. Wildfires were perceived as a serious problem in Turkey, Armenia and Greece but as a substantially less serious problem in Romania, Ukraine and Moldova. In Greece, Armenia, and especially Ukraine, the current designated protected areas are considered sufficient to maintain biodiversity, while in Romania, Turkey, and especially Moldova, more areas should be designated as protected. A major need in all countries (except for Turkey) is the increased use of information and communication technologies for both wildfire suppression and protected area management. Experts were divided on whether wildfire suppression and management of protected areas are interconnected. However, there is growing awareness of the adverse impacts of climate change in protected areas and the frequency of wildfires in the future. The most frequently suggested measures to alleviate these impacts were: changes in forest management and increasing public awareness for wildfire suppression, along with changes in forest management and increased staff training to enhance protected area conservation.

Vegetation on earth surface is the integral part of the world ecosystems in functioning for varying spatial and temporal scales. Along with other benefits, land-use as a forest can dramatically reduce the soil erosion and water pollution by protecting the soil surface from erosive effects of rainfall. The objective of this study was to determine rill/interrill (surface) erosion risk by using the RUSLE equation for Velikoy sub-watershed (417 km2) which has rich forest-resources within the Coruh River Basin located at northeastern Turkey. Land use and cover (C factor), rainfall and runoff (R factor), soil erodibility (K factor), slope length and steepness (LS factor), and management support practice (P factor) were identified as the sub-factors for the RUSLE equation and were multiplied to estimate soil loss by rill/interrill erosion. Results showed that the mean surface soil erosion from the sub-watershed was around 3.9 t ha-1 yr-1. Of the total study area, 8.2% was estimated as the areas of high and very high risk for the potential surface soil erosion that also indicates prioritization for the implementation of the erosion conservation measures.

Kuraklik orman ekosistemleri uzerinde etkili olan onemli ekolojik faktorlerden biridir. Bu faktorun yaratmis oldugu sorunlar son yillarda artan kuresel sicaklik ile artmis ve gelecekte daha da artmasi muhtemel gorulmektedir. Kuraklik bitkilerin toprak ustu biokutle artimini %30-70 oraninda dusurebilmekte ve uzun donemli oldugunda ise dogal yayilislarini ve cesitliliklerini sinirlayabilmektedir. Agaclarin buyumesi % 80-90 oraninda suyun elverisliligi tarafindan kontrol edilmektedir. Ulkemizde 1990 yili sonrasindaki kurak donemlerde Ic Anadolu, Karadeniz ardi kesimler ve Ege Bolgesinde cesitli orman agaci turlerinde kurumalar gorulmustur. Karadeniz Bolgesinde saricam (P. sylvestris L.) ve ladinlerde (P. orientalis (L.) Link.), Ic Anadolu bolgesinde karacamlarda (P. nigra Arn.), saricamlarda ve goknarlarda (Abies sp.), Ege Bolgesinde ise kizilcamlarda (P. brutia Ten.) kurumalar tespit edilmistir. Bahsedilen bu kurumalarin disinda kuraklik ve sicaklik artisina paralel olarak ladin ormanlarinda kabuk boceklerinin neden oldugu onemli oranda kurumalar gozlemlenmistir. Ulkemiz kosullarinda, kurakligin siddetli olmasi uzerinde cografi konumun yani sira, iklim degisimi, asiri otlatma, cayir-mera ve orman alanlarinin tarim alanlarina donusturulmesi ve siddetli erozyon gibi etkenlerde onemli rol oynamaktadir. Ulke genelinde 1949 yilinda 38.9 milyon ha olan cayir-mera otlak alanlari, 1969 yilinda 28.3 milyon hektara, gunumuzde ise yaklasik 21.8 milyon hektara dusmustur. Yine islenen arazi alani 1935 yilinda 8.5 milyon hektar iken bu miktar 1970 yilinda 25 milyon hektara, gunumuzde ise yaklasik 28 milyon hektara ulasmistir. 1950-1997 yillari arasinda meydana gelen orman alani kayiplari yaklasik 2.6 milyon hektardir. Kurakligin orman ekosistemlerine verecegi zararlari azaltmak icin onemli orman agaci turlerimizin kurakliga dayanikli orijinlerini veya ekotiplerini belirlemeye donuk bilimsel calismalarin bir an once yapilmasi gerekmektedir. Ayrica orman alanlarinin kuraklik risk haritalarinin cikarilmasi ve bu alanlarda agaclari kurakliga karsi direncli kilacak silvikulturel mudahaleleri gerceklestirerek agaclarin kurakliga hazirlanmasi gerekmektedir. Iklim projeksiyonlari gostermistir ki gelecekte ulkemiz daha da isinacagindan agaclandirma stratejileri buna gore sekillendirilmelidir; agac yetismeyecek derecede az yagis alan alanlarda dikim yapilmamali, eger yapilacaksa da yaprakli turler veya cali turleri tercih edilmeli, erozyon kontrolu ve otlandirma calismalarina daha fazla onem verilmelidir. Bu alanlara dikilen fidanlar kurak yillarda kuruyacagindan harcanan paralara yazik olacaktir. Ayrica, ulkemiz, kuraklikla ciddi sekilde mucadele etmek ve gerekli onlemleri almak zorundadir. Erozyonu azaltmak, toprak kaybini onlemek ve neticesinde orman ve tarimsal uretimi artirmak icin bu mucadele elzemdir.

Authors would like to thank the Central Finance and Contracts Unit (CFCU) in TURKEY and the EU INTERREG IV "Black Sea Basin Joint Operational Programme 2007-2013" framework that funded this project. In addition. we would like the staff members of the Kastamonu Regional Directorate of Forestry. Yasar Cakiroglu, Muzaffer Buyukterzi and Hidayet Kavi for their generous help and support. Aim: Readily available water resources are a key for wildfire suppression. Hydrologic models are a practical and essential tool for understanding the processes of hydrology and managing water resources, but have not been utilized as frequently for wildfire suppression. The goal of the present study was to use the Soil WaterAssessment Tools (SWAT) model to determine whether the stream water could be managed sustainably in wildfire suppression at the Bayam Forest District in Kastamonu Province, Turkey. Methodology: As an input file, the SWAT model used soils, land-uses, weather data and morphology of watershed based on the Digital Elevation Model (DEM). The model was applied for period 2001-2013 in order to predict the water budget of the study area and major streams within the studied district. Results: The analysis of the hydrologic water budget indicated that 70% (573.8 mm) of the annual precipitation (822 mm) was lost as evapotranspiration in the basin, whereas 19%, 34% and 47% of the remaining total water yield (234.6 mm) contributed to streams via surface runoff, groundwater flow and lateral flow, respectively. Interpretation: Overall, the result of SWAT model indicated to a certain degree promising findings on the availability of stream water and optimal placement of water reservoir for the use of wildfire suppression.

Agricultural activities such as row-cropping and grazing, have accelerated stream bank erosion. Accelerated stream bank erosion increases nonpoint source pollutants in aquatic ecosystems, significantly degrading them. Mitigating stream bank erosion is a priority worldwide, especially in agricultural watersheds. The objective of this study was to analyze the impacts of riparian land-use management on stream bank erosion and deposition, along with analyzing its temporal and spatial patterns. The study was conducted in three regions of Iowa (central, northeast and southeast) along 30 stream reaches adjacent to seven different riparian land-uses. The riparian land-uses were riparian forest buffers, grass filters, pastures with the cattle excluded from the stream, intensive rotational grazing, rotational grazing, continuous grazing and row crop fields. Seasonal erosion and deposition data (Spring, Summer and Autumn) were collected along these reaches for 5 years and yearly for the following two years. To analyze the data, conventional statistical methods (ANOVA and Tukey's test) along with innovative techniques (percentile plots, cumulative erosion curves and bubble charts) were utilized. Based on the analysis, of this extensive in time (seven years) and large in size (1500 pins measured 17 times in three regions) field dataset, major results were obtained in regard to stream bank erosion in Iowa, USA. Stream banks exhibited high year-to-year variation in erosion and deposition showcasing the need for long-term datasets to better understand stream bank erosion and deposition. Seasonal erosion, also had high variability with Spring recording the most erosion followed by Summer and Autumn. Certain seasons exhibited high stream bank erosion indicating that managers need to focus on these seasons, to reduce erosion effectively. In addition, seasonal measurements can highlight depositional events that might be masked with annual measurements. Riparian land-uses significantly impacted stream bank erosion. Riparian forest buffers and grass filters significantly mitigated stream bank erosion while traditional agricultural practices like continuous grazing and row-crop agriculture had accelerated stream bank erosion. Finally, the percentile plots, cumulative erosion curves and bubble charts captured some stream bank responses that would have been unnoticed using conventional statistical methods, allowing decision makers, stakeholders and the general public, to support and approve measures to mitigate this environmental problem. Nature-based solutions utilizing riparian perennial vegetation can sustainably mitigate stream bank erosion.

Stream bank and gully erosion are major sources of nonpoint source pollutants, especially in landscapes dominated by agriculture. Implementation of upland conservation practices in landscapes dominated by agriculture reduces upland sediment transport more than water runoff, leading to excessive stream bank and gully erosion. This review focus on ten different studies conducted in streams in Iowa that investigated riparian land-use impacts on stream banks, gullies, and other riparian sediment sources (cattle loafing areas and cattle stream access points). The riparian land-uses investigated were riparian forest buffers; grass filters; continuous, rotational, and intensive rotational pastures; pastures with cattle fenced out of the stream; and row-cropped fields. Results of these studies indicate that maintaining perennial deep-rooted vegetation in riparian areas and excluding cattle from the stream channel stabilizes stream banks and gullies. Cattle loafing areas and cattle stream access points appear to also be important sediment sources. Re-establishing perennial riparian vegetation is a sustainable and cost-effective conservation practice because it reduces sediment in streams while maintaining the majority of the watershed in agricultural production. The limited available funds for the implementation of holistic watershed conservation practices suggest using targeted approaches, at the watershed scale, to improve conservation practice effectiveness.

Livestock grazing of riparian zones can have a major impact on stream banks if improperly managed. The goals of this study were to determine the sediment and phosphorus losses from stream bank soils under varying cattle stocking rates and identify other factors that impact stream bank erosion in the Southern Iowa Drift Plain. The study was conducted on thirteen cooperating beef cow-calf farms within the Rathbun Lake watershed in South Central Iowa. Stream bank erosion rates over three years were estimated by using the erosion pin method. Eroded stream bank lengths and area, soil bulk density and stream bank soil-P concentrations were measured to calculate soil and total soil-P lost via stream bank erosion. Results revealed that the length of severely eroded stream banks and compaction of the riparian area were positively related to an increase in number of livestock grazing on the pasture stream reaches. While there was no direct relationship between bank erosion and stocking rate, the erosion rates from two sites enrolled within the Conservation Reserve Program (CRP) were significantly lower than those from all grazed pasture sites especially when seasonal effect, specifically winter/spring, was considered. This result suggests that use of riparian areas as pasture has major negative impacts on water quality and channel integrity through increased sediment and phosphorus from bank erosion, and that impact could be reduced through management of livestock grazing within these riparian areas.

Livestock grazing of riparian areas can have a major impact on stream banks and stream integrity if improperly managed. The goals of this study were to determine the sediment and phosphorus (P) losses from stream bank soils under varying cattle stocking rates and to identify additional factors that impact stream bank erosion in the southern Iowa Drift Plain. The research was conducted on 13 cooperating beef cow-calf farms within the Rathbun Lake Watershed in south central Iowa. Over three years, stream bank erosion rates were estimated by using an erosion pin method. Eroded stream bank lengths and area, soil bulk density, and total P (TP) content in stream bank soil were measured to calculate soil and TP losses via stream bank erosion. The length of severely eroded stream banks and soil compaction of the riparian areas of the pastures were positively related to stocking rates. There was no direct relationship between bank erosion and stocking rate. These results suggest that use of riparian areas as pasture can negatively impact the integrity of the major source areas and that the impact could be reduced through management of livestock stocking densities within these riparian areas.

Tufekcioglu, Mustafa, Richard C. Schultz, George N. Zaimes, Thomas M. Isenhart, and Aydin Tufekcioglu, 2012. Riparian Grazing Impacts on Streambank Erosion and Phosphorus Loss via Surface Runoff. Journal of the American Water Resources Association (JAWRA) 1-11. DOI: 10.1111/j.1752-1688.2012.12004.x Abstract: Surface runoff is one of the major pathways of sediment and phosphorus (P) transport to surface waters. Rainfall simulations were conducted on nine grazed pasture sites with different stocking rates in three different Iowa (United States) regions. The purpose of the simulations was to determine the impacts of cattle grazing on the amounts of sediment and P in surface runoff within a 15-m wide strip on both sides of the stream from different source areas (SAs). These riparian SAs included stream-side loafing areas, cattle streambank access paths to the stream, and the other vegetated areas adjacent to the streambanks. The runoff samples collected during the simulations were analyzed for suspended sediment (SS) and total phosphorus (TP). Soil bulk density and antecedent soil moisture samples were collected around the rainfall simulation plots to identify differences in compaction, infiltration, and surface runoff among the SAs. SS and TP losses from access paths and loafing areas within the 15-m wide strips accounted for up to 72 and 55% of the total losses, respectively, even though they accounted for only 2.7% of the total area within the 15-m wide strips. This suggests that access paths and loafing areas require special attention to mitigate the impacts of cattle on stream water pollution. Significant correlations were found between stocking rates and both SS and TP losses suggesting that low stocking rates can reduce sediment and P export to streams from the SAs.

Grazing at high stocking rates may increase sediment and nutrient loading of pasture streams through transport in precipitation runoff and bank erosion. A 3-yr (2007–2009) grazing study was conducted on 13 cool-season grass pastures to quantify effects of stocking rate and botanical composition on forage sward height, proportions of bare and manure-covered ground, and bank erosion adjacent to streams. Pastures ranged from 2 ha to 107 ha with stream reaches of 306 m to 1 778 m that drained watersheds of 253 ha to 5 660 ha. Bare and manure-covered ground were measured at a 15.2-m distance perpendicular to the stream at 30.5-m intervals at up to 30 locations on each side of the stream by the line transect method in May, July, September, and November of each year. At the midpoint of the 15.2-m line, forage sward height was measured with a falling plate meter (4.8 kg · m -2 ) and plant species identified. In November 2006, fiberglass pins (1.6 × 76.2 cm) were driven 73.7 cm into the stream bank at 1-m intervals from the streambed to the top of the bank along 10 equidistant transect locations on each side of the stream to measure bank erosion during spring, summer, and fall of each year. Increasing pasture stocking rates increased manure-covered ground and decreased sward height, but did not affect proportions of bare ground. The greatest, intermediate, and least net soil erosion rates occurred during the winter/early spring, late spring/early summer, and late summer/fall seasons. Stocking rates between measurements, expressed as cow-days · m -1 stream, were not related to bank erosion. Increasing stocking rates per unit of stream length will increase manure cover and decrease forage sward height, but not affect proportions of bare ground or bank erosion rates adjacent to pasture streams. Therefore, managing stocking rates may reduce nutrient loading of pasture streams.