Neural network modelling of rainfall interception in four different forest stands

The objective of this study is to reveal whether it is possible to predict rainfall, through fall and stem flow in forest ecosystems with less effort, using several measurements of rainfall interception (hereafter ‘interception’) and an artificial neural network based linear regression model (ANN model). To this end, the Kerpe Research Forest in the province of Kocaeli, which houses stands of mixed deciduous-broadleaf forest (Castanea sativa Mill., Fagusorientalis Lipsky, Quercus spp.), black pine (Pinus nigra Arnold), maritime pine (Pinus pinaster Aiton) and Monterey pine (Pinus radiata D. Don), was selected study site. Four different forest stands were observed for a period of two years, during which rainfall, throughfall and stemflow measurements were conducted. These measurements were separately calculated for each individual stand, based on interception values and the use of stemflow data in strict accordance with the rainfall data, and the measured throughfall interceptionvalues were compared with values estimated by the ANN model.In this comparison, 70% of the total data was used for testing, and 30% was used for estimation and performance evaluation. No significant differences were found between values predicted with the help of the model and the measured values. In other words, interception values predicted by the ANN models were parallel with the measured values. In this study, the most success was achieved with the models of the Monterey pine stand (r2 = 0.9968; Mean Squared Error MSE = 0.16) and the mixed deciduous forest stand (r2 = 0.9964; MSE = 0.08), followed by models of the maritime pine stand (r2 = 0.9405; MSE = 1.27) and the black pine stand (r2 = 0.843, MSE = 17.36)

Ecohydrological Effects of Run-of-River Type Hydroelectric Power Plants on The Watersheds

Hidroelektrik santrallerinin kurulum aşamasında meydana gelen orman kesimi, hafriyat depolama, yol yapımı, topraklarda kompaktlaşma gibi olumsuzluklar ile işletim aşamasında doğal akış özelliklerinin değişmesi, sucul organizmaların göç yollarının tıkaması, enerji nakil hattı geçişi, ilave yolların yaratacağı zararların yaban hayvanları ve ekosistemler üzerinde bir takım olumsuz etkilere yol açması kaçınılmazdır. Ortaya çıkabilecek olumsuzlukların ya da kötüye gidişin etkilerinin en hızlı ve açık biçimde görülebileceği yerler akarsular ve bünyelerindeki habitatlardır. Fakat dere ekosistemlerinin sağlık ve doğallıktan uzaklaşma (entegrasyon) düzeyini ortaya koymak ve bununla bağlantılı olarak nehir tipi hidroelektrik santrallerinin etkilerini en iyi şekilde değerlendirmek ekohidrolojik anlamda mümkün olabilmektedir. Bu gerçekler, ülkemizde üzerine kurulduğu nehir tipi HESleri barındıran havzalarda bilimsel açıdan havza ölçeğinde ekosistemlerin devamlılığını gözetecek ekohidrolojik ağırlıklı bir değerlendirme yapılması gereksinimini gündeme getirmektedir. Bu makalede nehir tipi hidroelektrik santrallerinin ekohidrolojik etkilerini ortaya koyabilecek değerlendirme metodolojisinin ana hatları irdelenmiştir

Evaluation of Some Streamwater Quality Parameters Using with Multiple Statistical Methods in Mature Pinus sylvestris L. Forest Ecosystems

Aim of study: The main purpose of this study is composed to determinations of indicator water quality parameters of Oltu stream

Evaluation of some streamwater quality parameters using with Principal Component Analysis (PCA) in mature Pinus sylvestris L. forest ecosystems

Aim of study: The main purpose of this study is composed to determinations of indicator water quality parameters of Oltu stream

DETERMINATION OF HYDROLOGICAL-HYDROCHEMICAL PARAMETERS AND MACROINVERTEBRATE VARIABILITY IN FORESTED WATERSHEDS BY CANONICAL CORRELATION ANALYSIS

Recently, ecological water monitoring has become one of the fundamental issues of stream ecology. Out of biotic communities living around streams, macroinvertebrates are commonly used as water quality indicators. In this research, quantitative distributions of macroinvertebrate groups, living on a stream in the Belgrad Forest which represents a status close to the natural one and thus becomes a reference field with this property, were determined and it was explained how the change observed in the hydrological/hydrochemical conditions caused population interaction on the species. Relationships between macroinvertebrate species and environmental hydrological/hydrochemical parameters were established through Canonical Correlation Analysis. It was found that there were strong relationships between Heptagenia sulphurea species and dissolved oxygen amount as well as Potamon fluvitilis and organic substance amount. It was also detected that population of Gammurus pulex increased under conditions with increasing magnesium, nitrate nitrogen amounts and flow- rates