Macrophytes represent one part of the biological quality elements defined by the European Water Framework Directive (WFD) as ‘macrophytes and phytobenthos’. The aim of this study was to evaluate the reliability of ecological status classification by the use of macrophytes for lowland rivers with different habitat conditions, corresponding to EWFD requirements. The classification of water quality is based on the Ecological Quality Ratios (EQRs) which is proposed for the purpose of macrophyte-based classification for the WFD. To determine the ecological quality ratio, we calculated the following indices: River Macrophyte Nutrient Index (RMNI), River Macrophyte Hydraulic Index (RMHI), Macrophyte Index for Rivers (MIR), Number of macrophyte taxa which are not helophytes (NTAXA). Water sources that supply Lepenci River are located in alpine and subalpine areas of the Sharri mountain, which are considered as ecologically clean. Our results show that the water in spring area is clean but as a result of the anthropogenic activities downstream, the river becomes polluted by different pollution substances. This fact is also confirmed by the presence or absence of macrophytes that we used in this work as a biological indicator of water pollution. River Macrophyte Hydraulic Index (RMHI), has shown the highest value at SP6-Gërlicë, with a value of 8.74 that classifies this station downstream the river as the most polluted. The water flow velocity in this station is smooth and as such it is characterized with Macrophyte species associated with this type of water flow. According to the assessment of ecological status with RMNI index, the stations SP7-Kaçanik and SP8-Hani i Elezit, have good water quality and high ecological status and belong to first class (I), whereas the station with poorest water quality (fourth class) and poorest ecological status is rated SP5-Nikë. MIR index classify the quality of water as very good at S8-Hani i Elezit, whereas the values of this index at stations S5-Nikë and S6- Gërlicë indicate the bad water quality and poor ecological status. The largest number of macrophyte species that were not heliophytes was recorded in SP8-Hani i Elezit. We can conclude that the presence of macrophyte species in river varies from nutrient levels in water. Our results show that values of macrophyte based indices reflect the water quality in sampling stations therefore we can consider them as a reliable instrument for the assessment of the ecological status of the rivers.

Benthic macroinvertebrates are used to evaluate water quality in 8 sampling stations in Lepenci river basin in Kosovo. Sampling was performed in spring, summer and fall 2017. Following biotic indices are used: EPT taxa richness, Biological Monitoring Working Party (BMWP), Average Score per Taxon (ASPT), Stroud Water Research Center index (SWRC), Family biotic index (FBI), as well as diversity indices: Shannon-Weaver index (H), Simpsons index (D), Hill’s index (Hi), Mergalef index (D_Me) and Menhicnik’s index (D_Ma). Our results show the presence of 34 macroinvertebrate taxa in Lepenci river which belong to Insecta, Crustaceans and Annelidae. The water quality along the river show variation from high and good class upstream, to moderate, poor and bad, downstream. The Pearson’s bivariate correlation used to analyze the relationship between physicochemical parameters with biotic and diversity indices showed a significant correlation (p < 0.01) of EC, TSS, O₂, COD, BOD, NH_4, and PO₄^3- with biotic indices EPT, BMWP, ASPT, SWRC, FBI. We can conclude that the values of biotic and diversity indices have shown differences in water quality between polluted and unpolluted sites and reflect the ecological status of the river, therefore we can consider them as valuable tools for water quality assessment in rivers in Kosovo.

Water represents an essential element for life and living things on earth. Aquatic ecosystems play a decisive role in socio-economic development in urban and rural areas. In recent decades there have been concern at the global level with regard to the deterioration of aquatic...

Macrophytes are important elements of aquatic ecosystems that grow in or near water. Their taxonomic composition, species diversity, depth, and density are indicators of environmental health; as such, Macrophytes are used to assess the ecological status of water bodies. Under the aim of assessing the ecological status of the Klina River in Kosovo, a survey was conducted at eight sampling sites along the river course to analyze macrophyte composition, diversity, density, and cover. Three samples were collected at each sampling site from early June to late September. The following macrophyte indices were used to assess the ecological status of the river: Macrophyte Index for Rivers (MIR), River Macrophyte Nutrient Index (RMNI), and River Macrophyte Hydraulic Index (RMHI). Our sampling area included the upper reaches of the river where no organic pollution was detected (oligotrophic), the middle reaches where polluted water from farms is discharged into the river, and the lower reaches characterized by heavy organic pollution from settlements and various industrial activities. There is a positive correlation (p < 0.05) between water temperature, turbidity, electrical conductivity (EC), total dissolved solids (TDS), orthophosphates (PO₄³⁻), ammonia (NH₄⁺), nitrites (NO₂⁻), calcium (Ca²⁺), and potassium (K+) with plant density, RMNI, RMHI, EQR-RMNI, EQR-RMHI, and MIR. Sodium (Na+) has stronger positive correlation (p < 0.01) with RMNI and RMHI indices and negative correlation with EQR-RMNI and EQR-RMHI. Our results show that ecological status along the river varies from high and good upstream to poor, bad, and moderate running downstream.