Kentiçi Yol Ağaçlandırma Kriterleri İstanbul'daki Örnek Caddelerin İncelenmesi

Abstract

Kentlerdeki yeşil alanların yetersizliği nedeniyle buralarda yaşayan insanların biyolojik ve psikolojik bakımdan olumsuz etkilenmekte olduğu bir gerçektir. Yeşil alanların yetersizliği, kentlerdeki oksijen oranının düşmesine, sıcaklık artmasına, dinlenme mekanlarının daralmasına, görsel kirliliğe, gürültü çoğalmasına vs neden olur. Yetersizliği söz konusu olan yeşil alanların önemli elemanlarından birisi yol ağaçları dır. Bunlar, yollara ve dolayısı ile kentlere hareket ve canlılık getirici; kentteki birçok olumsuz koşulu iyileştirici bir faktördür. Kent peyzajı için yeterli parasal kaynak ayrılmaması, teknik elemanların yetersizliği ve bu konuya gerekli önemin verilmemesi nedeniyle: 1. Yeni yol ağaçlandırmaları istenilen nicelik ve nitelikte olmamakta, 2. Mevcut yol ağaçlarının bakım ve koruması da yetersiz kalmaktadır. Ülkemizin en önemli kenti olan İstanbul tüm bu olumsuz özellikleri bünyesinde bulun durmaktadır. Dünya tarafından kabul edilen, estetik ve kültürel bir kent olan İstanbul, plansız kentleşme nedeni ile estetik ve yeşil görünümünden uzaklaşmaktadır. Bu doğrultuda tez çalışmamda; "yol ağaçlarının kent içi etkileri, yol ağaçlandırması kri terleri ve İstanbul'da örnek birkaç caddenin yol ağaçlandırmaları incelenmiştir.

It is obvious that, people living in cities are biologically and psychologically disturbed because of insufficiency of green sides in the cities. Since green sides are insufficient in cities, oxygen level is low, it is hotter, recreational green sides are short, it is visually bad, it is more noisy, etc. Trees are one of important factor for improving the environment made worse by building crowdence and coarse environmental dirtiness. Moreover they are helpfull for keeping the visual and functional effects on people. Trees in cities are similary important for such factors. The place is made attractive by different form, texture, color and dimension properties of trees. People are positively impressed by trees along a road having different color, form and dimension. Moreover we shoul not forget following functions of trees directing directing drivers, comfortable and reliable walking, cool shadows. Considering city health by means of city afforestion, climate is made better, air pollution and noise arwe dicreased. However, it is not easy to adopt trees into hard city conditions. Tees in Cities should be resistant to strong winds, heavy sun shine, quick temperature changes and freeze, and they shoul need just poor soil (ASLANBO?A, 1982) Main factors affecting growing up of a tree are, climatic, chemical and phsical. Climatic factors are temperature, light and air pollution. City climate mainly differs from urban climate in temperature because of the building population in cities. Heat is absorbed by building walls in daylight and itis released back in the night. In cities having over %60 building density it is much more hotter. Chemical characteristics of soil means acid and feeding elements rote in soil Physical characteristics of soil means, texture, structure, soil- water relations, air in soil and temperature rate. For city afforestation health, aestetic and functional characteristics should be concerned. As mentioned above, crty condsition in cities are hard for trees to grow IX up. Therefore, it is essential to know the enviromental conditions and to take the necessary technical actions. In Turkey because of high increase rate of population, sub constructions and others are not efficiently carried out because of economical respect. As a result, afforestation is carried out without a program or a systematic and resulted with failure. To be succesfull in road afforestation functionally, tress selected should be selected so that they confirm the enviromental conditions. While selecting aooropiate types to fit into enviroment echological conditions, physical and enviromental factors should be encountered. Moreover, aesthetical and functional suplements of selected tree types should also be considered. While studiying afforestation of a street, determining and encountering the enviromental growing up conditions is very important. It is possible to use types of trees in afforestation. However, if selected type or types iare not approptiate according to enviromental growing up conditions, money and time spend will be lost. İn addition technically to the it is not possible to succeed without giving attention to the standards. One of these standards is the dimention in between the trees. It chances according to several enviromental factors. For example, ligt requist of the building, width of the road, usage purpose, and other elements used. Generally, I trees planted 6-1 5 meters ahead of eachother in rule. To suceed in planting young trees, they should be selected so that to fit hard and special conditions, to be durable and thry shoul be replace once. Moreover, planting grave dimentions should be appropiate to fit the dimensions of the tree. Furthermore if the soil of the planting side is not proper, it should be replace with the proper soil beforehand. After planting, care should be taken to the trees. The most importent one is irrigation. For newly planted road trees, if the rain is not enough, water gaining capacity of the soil is low, and underwater sources are deep, they should be irrigateds. (ASLANBO?A, 1980). For irrigation it is the most proper in the mominig or in the evening..Other aftercare functions are cultivating, fertilizing and trimming...*- While studing afforestation of important streets in the world, I have found out that they are all fit the cirteiras. My points from the study are: 1. forestation is such that to shadow wall and asphalt face of the streets (Shadowing criteria) 2.Trees are made dominant by using different trees in form, color and dimebtion. 3. Good Plan 4. Good aftercare studies 5. Daily and future planning studies 6. Living sides are put into the streets by means of trees groups 7. All the elements making upthe streets (buildig, roads, walking-riding-cycling ways, old trees)are encountered to gain integrity. We can reallise that, All the succesfull afforestrations have a good pre-plan. Connecting the faults after planting is hard and costly. Therefore, pre-planning phase is very important and should be carried out properly sstisfactory people. I have analyssed three different street afforestrations in İstanbul to see the sattisfactoriness of new old afforestrations. These şre: Bağdat Streets; Most important street of anatolian site of the city, road afforestration was started in 1950's, pepole and authomobile traffic is crowded, andthere are shopping facilities on both sides of the street. Caddebostan-Bostanci beach street road; new afforestration studies are conbinueing next to the sea. and have a crowded people-authomobile traffic at the weekends. Bahariye Streets;shopping centre, dosed to authomobile traffic and used for walking way. If the presedent situation of these streets is analysed according to road afforestration; Platanus orientals is used as planted tree types in Bağdat street. These trees had been planted diagonally, 10-15 meters ahead of each other in lines XI in green bands along the street in 1950's There are trees on both sides of almost all along the street. Bodies of the trees are generally smooth and symmetrical. They are periodically trimmed in order not to disturb both people and authomobile traffic. Moreover; Quercus robur, Pinus brutia, Magnoli grandiflora, Aesculus comae, Cedrus libani, Cedrus atlantica, Pinus pinea, Robinia pseudoacacia had been planted as trees. Caddebostan-Bostanci beach road afforestation was carried on in 1997. Following tree types had been used: Albizzia julibrişşim., Robinia pseudo acacia, platanus orientalis, Aesculus hippocastanum, Pinus pinea, Prunus psifera pisardii nigra. Almost all of the trees had been planted in 1 997. While planting the distances in between the trees had not been planted. Some of the trees are too slose to each other and this will most probably result in some profor example blems. Additionally, aftercare studies are not enough. Example protective support elements seem to be damaged. As a result, some of the trees cannot survive at all. Bahariye Street has two sections First one is forbidden to authomobile traffic and second one is open authomobile traffic in a specified time period. There are tall building on both sides of the street and this result a shadow street trees are planted in a green band in the middle of the street. These bands are encircled by steel profiles to protect the green side. Road plannig studies had been carried out in 1992-1997. ;Following tree types are u.id: Picea pungens 'Glauca', Picea orientalis, Cedrus atlantica 'Glauca' Chamaecyparis lawsoniana, Thuja orientalis, Albizzia julibrişşim, Morus alba 'Pendula', Phoenix canariensis, Robinia pseudo acacia, Platanus orientalis. Improper planting distances will most probably result several problems in the future. To sum up as I have pointed out in analyzing successfull road afforetration examples in the World, it is earned out with a good beginning plan which includes futuresite, and this plan regularly carried out. On these streets, trees are planted very uniformly, and while planting street location, length, wideness and functionality are all encountered. X According to my sample study in İstanbul three different streets I have found out that the best was Bağdat Street. Positions, fitness and visually plane trees are very well along the street. Bcause of good trimming their bodies are long and smooth. Considering Caddebostan-Bostanci beach road afforestation studies, after operational plans planting had been carried out without any systematic. As far as I have heard from the municipality, replanting is being planned. This result in high costs and lous chance of success. For afforestation of Bahariye Street different types in form, color and type had been used. Now they seem to be welll organised and planned However, in the future when they will get bigger, it will be hard to walk in this street and trees will be squeezed in between the buildings. For successful road afforestation, primilary municipality has to have an action plan. Satisfactorily educated experts should be assigned with enough amount of budget to make up plans and perform the plans.