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Determination of flood peak discharges in some pond watersheds and analysis of agricultural drought of Bilecik
Get PDFİklim Değişikliği ve beraberinde yaşanan taşkın ve kuraklık su kaynaklarını önemli düzeyde etkilemektedir. Su kaynaklarını en çok kullanan sektör de tarım sektörüdür. Bu yüzden; havzaların tarımsal su yönetimi planları yapılmalıdır. Bu çalışmada; Bilecik ilçelerindeki başlıca üretilen tarım ürünlerinin, taşkın ve kuraklık açılarından etkileşimleri incelenmiştir. Bu amaçla Bilecik’teki tarımsal ürün verilerine TÜİK’ten ulaşılmıştır. Bilecik ilçelerinin iklimsel verilere Bilecik Meteoroloji Müdürlüğünden, havza verilerine ise Devlet Su İşleri (DSİ) Bölge Müdürlüğünden ulaşılmıştır. Çalışmada, taşkın analizi Gölpazarı’ndaki Arap deresi, Delikbağ deresi; Pazaryeri’ndeki Gümüşdere; Yenipazar’daki Çöte havzaları kullanılmıştır. Havzaların özellikleri (alanı, uzunluğu, eğimi, eğri numarası) ve iklim verileri hazırlanıp, WinTR-55 ve DrinC modelinde kullanılmıştır. Sonuçta; RDI Kuraklık indeks sonucu ve şerbetçiotu verimi arasındaki R2 değeri, kıyaslanan ilçeler arasında en yüksek değere Bilecik Merkez’de 0.195’lik değerle ulaşmıştır. RDI kuraklık indeks sonucu ve buğday verimi arasındaki R2 değeri, kıyaslanan ilçeler arasında en yüksek değere Bilecik Merkez’de 0.31 değerle ulaşmıştır. Ayrıca; Bilecik’te 2017 yıllında kuraklık indeks değerlerinde önemli bir azalış gözlemlenmiştir. Bozüyük’te kuraklığın en belirgin olduğu yıllar 2006 ve 2007 olarak görülmektedir. Pazaryeri'nde ise 2007 yılı, kuraklığın etkisinin en yoğun hissedildiği yıl olarak görülmektedir. WinTR-55 modeliyle 100 yıllık tekerrür süresine ait pik debi değerleri kıyaslandığında; Gölpazarı-Arap Deresi 66,59 m³/s ile en yüksek riske sahip alandır. Bunu 47,06 m³/s ile Gölpazarı-Gümüşdere, 47,00 m³/s ile Gölpazarı-Delikbağ Deresi ve 26,27 m³/s ile Yenipazar-Çöte takip etmektedir. Gelecekteki araştırmalar, farklı bitki çeşitlerinin kuraklığa karşı tolerans seviyelerini ve kuraklığın tarımsal üretim üzerindeki etkilerini azaltmak için geliştirilebilecek adaptasyon stratejilerini incelemeye odaklanmalıdır. Tarımsal su yönetimi çalışmalarında, neticede sel-kuraklık-su kirliliği riski haritaları oluşturulmalıdır. Çiftçileri bilinçlendirmek için, bu afetlere karşı farkındalık ve eğitim çalışmaları yapılmalıdır.Climate change, and the accompanying floods and droughts, significantly impact water resources. Since the agricultural sector is the largest consumer of these resources, comprehensive agricultural water management plans must be developed for the basins. This study examined the interactions between the main agricultural products cultivated in the Bilecik districts and the effects of both floods and droughts. For this purpose, agricultural product data for Bilecik were obtained from TÜİK (Turkish Statistical Institute). Climatic data for the Bilecik districts were acquired from the Bilecik Meteorology Directorate, and basin data were supplied by the State Hydraulic Works (DSİ) Regional Directorate. For the flood analysis, the following basins were used: the Arap Stream and the Delikbağ Stream in Gölpazarı; the Gümüşdere in Pazaryeri, and the Çöte Basin in Yenipazar. Basin characteristics (area, length, slope, curve number) and climatic data were prepared and utilized within the WinTR-55 and DrinC models. The results showed that the R2 value for the relationship between the RDI drought index and hop yield reached its highest value among the compared districts in Bilecik Center, with a value of 0.195. Similarly, the R2 value for the relationship between the RDI drought index and wheat yield reached its highest value in Bilecik Center, with a value of 0.31. Furthermore, a significant decrease in drought index values was observed in Bilecik in 2017. The years 2006 and 2007 were determined to be the most pronounced drought years in Bozüyük. In Pazaryeri, the year 2007 was identified as having the most intense drought impact. When comparing the peak discharge values for the 100-year recurrence interval using the WinTR-55 model, the Gölpazarı-Arap Stream area presents the highest risk with 66.59 m3/s. This is followed by Gölpazarı-Gümüşdere (47.06 m3/s), Gölpazarı-Delikbağ Stream (47.00 m3/s), and Yenipazar-Çöte (26.27 m3/s). Future research should focus on examining the tolerance levels of different crop varieties to drought and the adaptation strategies that can be developed to mitigate the impacts of drought on agricultural production. Finally, risk maps for flood-drought-water pollution should be created in agricultural water management studies, and awareness and education programs should be conducted to inform farmers about these hazards
Determination of climate change impacts on drought and wheat yield in Porsuk creek watershed
Get PDFTarımı etkileyen başlıca iklim olayı kuraklıktır. Bu çalışmada da; iklim ve kuraklığın tarıma etkisi, havza içerisinde detaylı analiz edilmesi açısından önemlidir. Çalışmanın amacı; Porsuk Çayı Havzası'nda iklim değişikliğinin tarımsal, meteorolojik ve hidrolojik kuraklık ile buğday verimine etkisinin belirlenmesidir. Bu tezde Porsuk Çayı Havzasında; geçmişteki (1970-2018) ve HadGEM2-ES küresel iklim modelinin iyimser (RCP4.5) ve kötümser (RCP8.5) senaryolara göre üretilmiş gelecekteki (2018-2100) iklim verileri kullanılarak; Standart Yağış İndisi (SYİ), Standart Akış İndisi (SAİ), Palmer Kuraklık Şiddeti İndisi (PKŞİ) ve WOFOST modeli yardımıyla kuraklık analizleri ve buğday verim analizleri yapılmıştır. Havzanın kurak bir bölgede yer aldığı anlaşılmışken; geçmişte özellikle hidrolojik ve tarımsal kuraklıkların hakim olduğu, meteorolojik açıdan normal bir iklimin hüküm sürdüğü tespit edilmiştir. Tarımsal açıdan kuraklığın şiddetli yaşandığı bölgeler sırasıyla; Odunpazarı, Alpu ve Tepebaşı şeklindedir. Geçmişte; 1981, 1986, 1989, 2008, 2013, 2015, 2018 yıllarının kurak geçtiği belirlenmiştir. Gelecekte; en kurak yılların 2056, 2058, 2069, 2070, 2089, 2096 yılları olması beklenirken; en sulak yılın 2021 olması beklenmektedir. Porsuk Çayı havzası gelecekte; meteorolojik açıdan kuraklaşma, hidrolojik açıdan ise sulaklaşma eğilimindedir. Tarımsal açıdan ise; zaman geçtikçe kuraklaşma potansiyeli mevcut olsa da, normal bir iklimin hakim olacağı tespit edilmiştir. Gelecekte hidrolojik açıdan en kurak yer Odunpazarı'dır. Porsuk Çayı havzasında, gözlenen ve WOFOST modeliyle tahminlenen buğday biyokütlesi değerleri arasında; 2016 yılı için + %23,8'lik fark ve 2017 yılı için + %1,2'lik bir fark tespit edilmiştir (2017 değerleri>2016 değerleri ve tahminlenen>gözlenen). Havzadaki iyimser senaryo sonuçlarına göre, yakın gelecekte (2020-2045) %0,73'lük buğday verim artışı beklenmektedir. Bunun dışındaki tüm dönemlerde, buğday verimlerinde (%0.43-1.5 arasında) azalma gerçekleşeceği tahminlenmektedir. Havzadaki iklim değişikliği; referans (1970-2000) dönemle kıyaslandığında, gelecekte sıcaklık ve yağış artışları şeklinde olacaktır. Sonuç olarak; WOFOST, gözlenen değerlerden daha büyük buğday verimleri tahminlemeye eğilimli olsa da, modelin gelecekteki buğday verimini tahminlemede güvenle kullanılabileceği düşünülmektedir. Bu çalışma sonucunda; karar vericilerin kullanması için, kuraklık periyotları ve bitki verim tahminleme ile ilgili önemli veriler üretilmiştir. Bu sayede; bölgede, kuraklık riski altındaki alan ve zamanlarda buğday tarımının planlanması, verim kayıplarının azaltılmasına yardımcı olacaktır.Drought is main climatic event affecting to agriculture. The purpose of the study is to determine the effect of climate change on agricultural, meteorological, hydrological drought and wheat yield in Porsuk Creek basin. Drought analyses and wheat yield analyses were carried out with the help of Standard Precipitation Index (SPI), Standard Runoff Index (SRI), Palmer Drought Severity Index (PDSI) and WOFOST model using the past (1970-2018) and future (between 1970-2100) climate data produced according to the optimistic (RCP4.5) and pessimistic (RCP8.5) scenarios of HadGEM2-ES global climate model in Porsuk Creek Basin. The analysis revealed that the basin was located in an arid region; it was determined that hydrological and agricultural droughts were dominant and a meteorologically normal climate prevailed in the past. Sub basin in the study area where agricultural drought is experienced severely are Odunpazarı, Alpu and Tepebaşı, respectively. 1981, 1986, 1989, 2008, 2013, 2015 and 2018 years were dry. While the driest years are expected to be 2056, 2058, 2069, 2070, 2089, 2096; the wettest year is expected to be 2021. Porsuk Creek basin tends to be drought meteorologically and wet hydrologically in the future. In terms of agricultural drought; Although there is a potential for drought over time, it has been determined a normal climate will prevail throughout the basin. Odunpazarı is the driest place hydrologically in the future. When compare the biomass values of the wheat observed in Porsuk Creek basin with estimated by WOFOST model; there were + 23,8% difference for 2016 and + 1,2% difference for 2017 (2017 values>2016 values and estimated>observed). According to the results of the models in the basin; 0,73% wheat yield increase is expected in the near future (2020-2045). It is estimated wheat yield will decrease (%0.43-1.5) in all other periods. Compared to reference (1970-2000) period; climate change will be in the form of temperature and precipitation increases in the future in the watershed. As a result; it is believed that WOFOST can be used in safe in predicting future wheat yield, Although the model tends to predict wheat yield higher than observed values. As a result of this study, important data on drought periods and crop yield estimation have been produced for use by decision makers. In this way; planning of wheat farming will be made as temporal and spatial under drought risk. So, it will help to reduce yield losses
Drought Analysis of Wheat in Humid (Wales) and Dry (Iraq) Conditions
Get PDFIt is necessity to examine the relationships between droughts and plant yields, which are affected by climate change. In this study, by choosing sample countries from the Middle East and Northern Europe, It was aimed to determine the relationship between wheat yields and drought. Considering that Wales represents the wet conditions and Iraq represents the dry conditions in the World, in this study, the drought conditions of these two countries were analyzed with standard precipitation index (SPI), standard runoff index (SRI) and palmer drought severity index (PDSI). In Cardiff, it was determined that the meteorological humidity increased and there is a normal climate in terms of hydrologic. This led to an increase in wheat yields. In terms of meteorologic drought, Iraq cities from arid to humid are Kirkuk, Mosul, Baghdad and Basra, respectively. Agriculturally, they are listed as Basra, Baghdad and Mosul, respectively. It was determined that wheat yield decreases in Iraq were caused by non-climatic factors. Generally, it was determined that drought periods spread homogenously throughout Iraq. Nevertheless, It is determined that drought is much more widespread and severe in Iraq in 2003, 2004 and 1964. In future dry years, production should be supported with irrigation and fertilization in Wales and Iraq
A research on applicability of small watershed hydrological model WinTR-55 to the basins of some small earth dams aimed at irrigation in Bursa
No full textBu tezde, Bursa İli bazı gölet havzalarında Mockus, Rasyonel ve DSİ sentetik yöntemleriyle bulunan taşkın debi değerleriyle USDA (Amerika Birleşik Devletleri Tarım Bakanlığı) tarafından geliştirilen ve küçük su havzalarına yönelik bir model olan WinTR-55 modelinin uygulanmasıyla bulunan taşkın debi sonuçlarını karşılaştırarak, modelin gölet havzalarına uygulanabilirliği araştırılmıştır. İncelenen on yedi havza içerisinden, Kestel Ağlaşan-Kayacık Kızılcıklıdere ve Gemlik Küçükkumla gölet havzaları dışındaki on beş havzada, WinTR-55 modelinin biraz daha büyük pik debiler tahminlemeye eğilimli olduğu görülmektedir. Modelin, küçük su havzalarında taşkın debilerinin hesaplanmasında emniyetli bir biçimde kullanılabileceği düşünülmektedir.The value of flood flow which occurs with usage of Mockus, Rational and DSİ sentetik method in some pond basins of Bursa compared with a model (WinTR – 55) that was developed by USDA (United States Department of Agriculture) for small watersheds in this thesis. In this study aimed to investigate the feasibility for various hydrological models, WinTR - 55 model was researched if flood flow results which the implementation of the ponds basins or not. Within seventeen basins on the thesis, except for Kestel Ağlaşan-Kayacık Kızılcıklıdere and Gemlik Küçükkumla pond basins, WinTR-55 model estimated greater peak flow. It is thought that the model securely could be used in the flow calculation
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
An investigation on the climate change and drought types in the Porsuk Stream Watershed, west of Turkey
Get PDFClimate change is a major parameter affecting agriculture. The aim of the study is to determine the effect of climate change on agricultural and hydro-meteorological drought in the Porsuk Stream Watershed. In this study, drought analyses in the watershed had been conducted using the past (1970-2018) and future (2020-2100) climate data produced according to the RCP 4.5 and 8.5 scenarios of the HadGEM2-ES model, with the help of Standard Precipitation Index (SPI), Standard Runoff Index (SRI) and Palmer Drought Severity Index (PDSI). The analysis revealed that the watershed was located in a dry region, it was detected that agro-hydrological droughts were dominant, and a meteorologically normal climatic situation prevailed in the past. Sub-basin in the watershed where agricultural drought is experienced severely are Odunpazari, Alpu and Tepebasi, respectively. 1981, 1986, 1989, 2008, 2013, 2015 and 2018 years were arid, while the driest years are expected to be 2056, 2058, 2069, 2070, 2089, 2096, the wettest year is expected to be 2021. The Porsuk Stream Watershed inclines to be dry meteorologically and humid hydrologically in the future. From the point of agricultural drought, although there is a potential for a drought over time, it is detected that a normal climatic situation will prevail throughout the watershed. Compared to the reference (1970-2000) period, climate change will happen in the manner of temperature and precipitation increases in the future. As a result of the study, important data about drought were produced for farmers
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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