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Öğe Identification of streamside landslides with the use of unmanned aerial vehicles (UAVs) in Greece, Romania, and Turkey(MDPI, 2023) Yavuz, Mehmet; Koutalakis, Paschalis; Diaconu, Daniel Constantin; Gkiatas, Georgios; Zaimes, George N.; Tüfekçioğlu, Mustafa; Marinescu, MariaThe alleviation of landslide impacts is a priority since they have the potential to cause significant economic damage as well as the loss of human life. Mitigation can be achieved effectively by using warning systems and preventive measures. The development of improved methodologies for the analysis and understanding of landslides is at the forefront of this scientific field. Identifying effective monitoring techniques (accurate, fast, and low cost) is the pursued objective. Geographic Information Systems (GISs) and remote sensing techniques are utilized in order to achieve this goal. In this study, four methodological approaches (manual landslide delineation, a segmentation process, and two mapping models, specifically object-based image analysis and pixel-based image analysis (OBIA and PBIA)) were proposed and tested with the use of Unmanned Aerial Vehicles (UAVs) and data analysis methods to showcase the state and evolution of landslides. The digital surface model (DSM)-based classification approach was also used to support the aforementioned approaches. This study focused on streamside landslides at research sites in three different countries: Greece, Romania, and Turkey. The results highlight that the areas of the OBIA-based classifications were the most similar (98%) to our control (manual) classifications for all three sites. The landslides’ perimeters at the Lefkothea and Chirlesti sites showed similar results to the OBIA-based classification (93%), as opposed to the Sirtoba site, where the perimeters of the landslides from OBIA-based classification were not well corroborated by the perimeters in the manual classification. Deposition areas that extend beyond the trees were revealed by the DSM-based classification. The results are encouraging because the methodology can be used to monitor landslide evolution with accuracy and high performance in different regions. Specifically, terrains that are difficult to access can be surveyed by UAVs because of their ability to take aerial images. The obtained results provide a framework for the unitary analysis of landslides using modern techniques and tools.Öğe Identifying the sources and the contributions of inland sediment and litter pollutants to enhance the Black Sea through nature-based solutions(Springer Nature, 2023) Zaimes, George N.; Koutalakis, Paschalis; Gkiatas, Georgios; Iakovoglou, Valasia; Marinescu, Mirela; Ristea, Oana; Ghulijanyan, Andranik; Gevorgyan, Luiza; Kuharuk, Ecaterini; Trombitsky, Ilya; Tüfekçioğlu, Mustafa; Yavuz, Mehmet; Tüfekçioğlu, Aydın; Duman, AhmetThe Black Sea is considered one of the most degraded regional seas. Efforts have been made to improve the conditions of the Black Sea, but little focus has been on the inland pollutants and litter, specifically from the rivers and streams that end in the Black Sea. Streams and rivers are significant sources of sediment and litter. This study aimed to identify the primary sources of sediment and litter and their contributions. This will help to suggest the optimal nature-based solutions to mitigate pollution sustainably. The study has five pilot areas in Greece, Romania, Armenia, Moldova, and Turkey. This will allow us to investigate different riverine ecosystems around the Black Sea and the implementation of different nature-based solutions. Surface and stream bank erosion methods are applied at different scales (plot and watershed) to estimate their contributions to the Black Sea. Traditional (runoff plots erosion pins) and innovative methods (laser scanning, unmanned aerial vehicles) are utilized. This way, areas with the highest erosion or litter will be targeted, and the optimal nature-based solutions based on the specific characteristics of these areas will be implemented.Öğe Innovative and sustainable use of stream water to suppress fires in protected areas: overview of the streams-2-suppress-fires project([y.y.], 2013) Zaimes, George N.; Tüfekçioğlu, Mustafa; Tüfekçioğlu, Aydın; Zibtsev, Sergiy; Kaziolas, Dimitrios; Yavuz, Mehmet; Trombitsky, Ilya; Emmanouloudis, Dimitrios; Uratu, Razvan; Ghulijanyan, Andranik; Borsuk, AnatoliiEstablishing protected areas to maintain biodiversity is a priority worldwide. Protected areas can have minimal management practices that can lead to the intensive accumulation of fire fuel. Fires are major threats for all protected areas that cause irreversible damages to them or impacts that last for decades or even centuries. The impending climate change impacts will increase the potential of large fires even in regions with minimal fires in the past. The emphasis of this project is in the Black Sea region with six pilot areas in six different countries. The first action involves the establishment of a Neighborhood Network regarding fire suppression around the region. The network includes institutions that are responsible for mitigating forest fires and managing protected areas from the Black Sea region. Another important action taken is to understand the fire behavior and locating the areas with the greatest fire risk. When considering fire suppression it is essential to know the available water resources (stream water). Since fires occur during the summer, the runoff and stream flow during this period needs to be accurately predicted. Based on the fire behavior and water resources data, the number, dimensions of the reservoirs required to suppress forest fires will be estimated for the pilot areas. Finally, specialized software will provide the optimal locations of the reservoirs and the best routes for the fire vehicles to reach the reservoirs. Overall the use of innovative mechanisms will lead to the more cost-effective management that will allow the sustainable development and protection of natural protected areas.Öğe Perspectives on protected area and wildfire management in the Black Sea region(Northeast Forestry Univ, 2020) Zaimes, George N.; Tsioras, Petros A.; Kiosses, Chrysovalantis; Tüfekçioğlu, Mustafa; Zibtsev, Sergiy; Trombitsky, Ilya; Uratu, Razvan; Gevorgyan, LuizaProtected 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.Öğe The relationship between erosion and precipitation and the effects of different riparian practices on soil and total-p losses via streambank erosion in Small streams in Iowa, USA(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Tüfekçioğlu, Mustafa; Zaimes, George N.; Kahriman, Aydın; Schultz, Richard C.Streambank erosion in agricultural landscapes contributes high amounts of sediment and total-P to surface water, resulting in the degradation of stream habitats and reduction in ecological services. Moreover, the implication of future climate change on bank erosion is also a growing concern. Streambank erosion rates from riparian forest buffers (RFo), grass filters (GFi), row-crops (RCr) and pastures, including fenced pastures (FPa), rotationally grazed pastures (RPa), intensive rotationally grazed pastures (IPa), and continuously grazed pastures (CPa), in three landform regions of Iowa, were measured over seven years. Bank erosion pins were measured seasonally (spring, summer and fall) in the first five years (2002–2006) and yearly for two more years (2007–2008). It was found that summer and spring seasons are the important ones since the relationships between erosion and precipitation were significantly “strong” in almost all the riparian practices, and precipitation was found to be the main factor driving streambank erosion. Streambank mean soil losses and soil total-P losses from RFo (23.3 tons km?1 yr?1 and 9.8 kg km?1 yr?1, respectively), GFi (31.1 and 9.9) and FPa (44.0 and 23.7) practices were all significantly lower than the grazing pasture practices, including RPa (142.3 and 58), CPa (255 and 105.1), IPa (234.6 and 122.7) and RCr fields (352.9 and 118.9). Also, RPa had significantly lower total-P loss than CPa, IPa and RCr practices (RFo, GFi, FPa < RPa < CPa, IPa, RCr). RCr practices had the highest streambank soil losses among all other riparian practices (RFo, GFi, FPa < RPa < IPa, CPa < RCr). The study showed that riparian conservation practices (RFo, GFi and FPa) showcased significant benefits in mitigating streambank soil loss and associated soil total-P load to streams. However, their effectiveness is highly sensitive to changing climatic conditions and the extent of spatiotemporal variations.Öğe Riparian grazing impacts on streambank erosion and phosphorus loss via surface runoff(Wiley, 2013) Tüfekçioğlu, Mustafa; Schultz, Richard C.; Zaimes, George N.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.Öğe Riparian land-use ımpacts on stream bank and gully erosion in agricultural watersheds: what we have learned(MDPI, 2019) Zaimes, George N.; Tüfekçioğlu, Mustafa; Schultz, Richard C.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.
