Ilıman Bir Türkiye Nehir Havzasında Dere Su Kalitesinin Çok Değişkenli Analiz ve Biyolojik Yaklaşımlarla Değerlendirilmesi

Year 2021, Volume: 17 Issue: 1, 34 - 55, 01.03.2021

Beyhan Taş , Özlem Yılmaz Fikret Ustaoğlu

https://doi.org/10.22392/actaquatr.751773

Cited By: 6

Abstract

Bentik algler indikatör türler içerir. Özellikle lotik ekosistemlerin ekolojik yapısının belirlenmesinde çok iyi bir göstergedir. Günümüzde insan faaliyetleri sular üzerinde birçok baskı oluşturmuştur, bunlardan besin zenginleştirmesi ekolojik durumu değiştiren en önemli su kalitesi sorunudur. Bu çalışmada Doğu Karadeniz Havzası içinde yer alan Elekçi Deresi’nin fiziko-kimyasal ve biyolojik (bentik diyatomeler) özelliklerinin ve su kalitesinin değerlendirilmesi amaçlanmıştır. Bir yıl boyunca aylık olarak üç farklı lokalitede örnekleme yapılmıştır. Yirmi farklı su parametresinin analizi zamansal ve mekânsal olarak değerlendirilmiştir. Yerüstü Su Kalitesi Yönetmeliği’ne göre akarsuyun su kalite sınıfı belirlenmiştir. Çok değişkenli istatistiksel analizler, su kalite indeksi (WQI), çeşitlilik indeksleri, klorofil-a, Palmer’ın pollusyon indeksi ve baskın cins skorları kullanılarak suyun trofik düzeyi ve su kalitesi değerlendirilmiştir. Yıllık ortalama değerlere göre, Elekçi Deresi amonyum azotu ve toplam fosfor parametreleri bakımından II. sınıf, serbest klor hariç (IV. sınıf) diğer su kalite parametreleri bakımından I. sınıftır. Elekçi Deresi’ndeki WQI değeri su kalite özelliğinin “mükemmel” olduğunu göstermiştir. Faktör analizinde, birinci faktöre göre nütrient elementleri su kalitesindeki değişikliklerden sorumludur. Diğer faktörlerdeki bileşenler jeolojik yapıdan ve klimatik faktörlerden oluşmaktadır.
Elekçi Deresi’nde toplam 93 bentik diyatome taksonu tanımlanmıştır. Navicula, Nitzschia, Cymbella ve Gomphonema en fazla kaydedilen taksonlardır. Cocconeis placentula var. euglypta, Gomphonema truncatum, Navicula lanceolata, N. tripunctata ve Nitzschia palea tüm istasyonlarda her mevsim bulunmuştur. Shannon ve Simpson çeşitlilik indeksi analiz sonuçlarına göre Elekçi Deresi “zayıf” düzeyde çeşitliliğe sahiptir, kirlilik düzeyi ise “orta”dır. Nemli subtropikal iklim bölgesinde bulunan Elekçi Deresi düzensiz rejimli bir akarsudur. Çevresel ve klimatik faktörler derenin diyatome komünitesini doğrudan etkilemiştir. Pollusyon indeksi sonucu çok hafif organik kirlilik tespit edilmiştir. Klorofil-a konsantrasyonuna göre derede ötrofikasyon riski yoktur. Dominant alg taksonlarının skor değerleri Elekçi Deresi’nin trofik seviyesinin “mezotrofik/mezo-ötrofik”, su kalitesinin “orta/orta-kirli” olduğunu göstermiştir. Genel sonuçlar, Elekçi Deresi’nin akış yönünde antropojenik faaliyetlerle ilişkilendirilebilen çeşitli kaynaklardan gelen kirleticilerle kontamine olduğunu ve diyatome çeşitliliğinin bu durumdan etkilendiğini göstermiştir.

Keywords

Biyoindikatörler, çok değişkenli analiz, diyatomeler, su kalitesi, trofik durum

Supporting Institution

Ordu Üniversitesi

Project Number

TF-1202

Thanks

Bu araştırma Ordu Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi tarafından TF-1202 nolu proje ile desteklenmiştir.

Assessment of Stream Water Quality in a Temperate Turkey River Basin by Multivariate Analysis and Biological Approaches

Abstract

Benthic algae include indicator species. Particularly, it is a very good indicator to determine the ecologic structure of lotic ecosystems. Nowadays, human activities have produced multiple pressures on waters, of them nutrient enrichment is the most important water quality problem that changed the ecological status. In this research, it is aimed to evaluate the physicochemical and biologic (benthic diatoms) properties and water quality of Elekçi Stream located in the Eastern Black Sea Basin. Throughout the year, samples from three different localities were collected monthly. Analysis of twenty water parameters were evaluated spatially and temporally. According to the Surface Water Quality Regulation, the water quality class of the stream has been determined. Trophic level and water quality of the stream were evaluated by using multivariate statistical analysis, water quality index (WQI), diversity indices, chlorophyll-a, Palmer’s index of pollution, and dominant genus scores. According to annual average values, Elekçi Stream is class II as to ammonium nitrogen and total phosphorus parameters. Also, it has class I in terms of other water quality parameters, excluding free chlorine (class IV). WQI value in the Elekçi Stream showed that the water quality feature is “excellent”. In factor analysis, the first factor showed that nutrient elements are responsible for changes in water quality. Components in other factors consist of geological structure and climate factors.
Total 93 benthic diatom taxa have been defined in Elekçi Stream. Navicula, Nitzschia, Cymbella, and Gomphonema genera are the most recorded taxa. Cocconeis placentula var. euglypta, Gomphonema truncatum, Navicula lanceolata, N. tripunctata, and Nitzschia palea were recorded in all stations every season. According to the analysis results of Shannon and Simpson diversity indices, Elekçi Stream has a “poor” level of diversity, and the pollution level is “moderate”. Elekçi Stream, located in the humid subtropical climate zone, is an irregularly flowed stream. Environmental and climatic factors directly affected the diatom community of the stream. As a result of the pollution index, very light organic pollution was detected. The stream does not carry eutrophication risk in terms of chlorophyll-a concentration. The scores of the dominant algal taxa showed that the trophic level of Elekçi Stream is “mesotrophic/meso-eutrophic” and the water quality is “moderate/moderately polluted”. General results showed Elekçi Stream is contaminated with pollutants coming from various sources that can be associated with anthropogenic activities downstream, and diversity of diatoms are affected by this sitıation.

Keywords

Bioindicators, multivariate analysis, diatoms, water quality, trophic state

Project Number

TF-1202

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