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Ecological patterns of water bug (Hemiptera: Heteroptera) assemblages in karst springs : a case study from central Montenegro

Gligorović B., Savić A., Protić L., Pešić V.

Oceanological and Hydrobiological Studies

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2016

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Vol. 45, No. 4

554--563

EN

The composition of water bug communities from 32 springs located in the central part of Montenegro was investigated. Twenty five species were identified, including 13 reported as new to Montenegro. The most common species were Hydrometra stagnorum and Velia sp. (Gerromorpha). Our study in the central part of Montenegro revealed that environmental and faunistic classification of karstic springs based on water bug communities may not correspond with each other. According to environmental characteristics, springs were divided into three groups indicating anthropogenic impact on the spring habitats. Water bug communities divided springs into four groups. There are differences in species richness between these four types of water bug assemblages and among the studied spring types. Results of CCA analysis revealed spring size as the main driver of biotic diversity of aquatic bugs in springs. Our study showed that community groups of water bugs specified in the biotic classification of spring habitats are much better defined than assemblages distinguished in the environmental site classification.

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Detrital components in submontane organogenic springs in relation to their morphology, microhabitats and macroinvertebrates

Ticha K., Simon O., Douda K., Kubikova L.

Polish Journal of Ecology

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2012

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Vol. 60, nr 1

163-175

EN

Fine particulate organic matter (FPOM), originated by aggregation of smaller particles and by decomposition of bigger particles, usually presents the dominant energy and nutrient source in the primary river net. Relationships between detrital components, environmental factors and macroinvertebrate composition were investigated in 52 submontane organogenic spring areas in small catchment in the Sumava foothills, Czech Republic. All three types of springs (helocrenes, rheocrenes and limnocrenes) were represented, as well as springs with the transitional character. The selected springs were permanent, with water discharge higher than 0.1 L s[^-1], they all were coldwater and stenothermic, with the winter water temperature at the point of the source ranging from 2.0 to 9.9[degrees]C. At each spring area, the main morphological and physical characteristics of the spring and surrounding area were recorded. Samples of detritus were collected (using the 2 mL sampling tube) from up to 5 microhabitats at each spring, usually macrophyte vegetation, point of the source, detrital deposition, sand, algal mat, leaf litter or moss, accordingly to the microhabitats, which were present. Macroinvertebrates were semiquantitatively sampled using a 15-cm circular sampler with 0.8 mm mesh, to the orders or lower taxa were determined. Water samples were taken, and analyses of the main physico-chemical factors were carried out. In our set of springs, organic substrate prevailed. Only small differences in the physico-chemical parameters (e.g. pH = 5.96 [plus or minus] 0.39; mean [plus or minus] SD) and low concentrations of nutrients (e.g. N-NO3[^-] = 0.79 [plus or minus] 0.86 mg L[^-1], ortho-PPO4[^-] = 0.0336 [plus or minus] 0.0275 mg L[^-1]) were noted, whereas studied geomorphological parameters and microhabitat types were more diverse. The proportion of basic microscopically differentiable components of the detritus was similar in all spring types and microhabitats. In all study sites, faecal pellet content was dominant in the detritus (49%) followed by plant residuals (26%) and amorphous matter (21%). High faecal pellet content is considered to be a consequence of a steadily low temperature in the springs. The correlation among the presence of macroinvertebrate groups and particular detrital components content was not significant, except for Trichoptera; the abundance of this group was positively correlated with the proportion of plant residuals in detritus in vegetation microhabitats. Faecal pellet content showed a weak negative correlation with N-NH4 concentration, which is probably the result of faster faecal pellet decomposition in springs with higher N-NH4 contents.

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Abiotic parameters determining fauna composition in karstic springs

Koperski P., Dumnicka E., Galas J.

Polish Journal of Ecology

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2011

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Vol. 59, nr 1

153-163

EN

The biotic diversity of springs is specific, which makes them valuable sites important for nature protection. Springs located in the Krakow-Częstochowa Upland (southern Poland) are characterized by low variability of environmental conditions, but their benthic fauna composition is considerably different. Benthic invertebrates, water chemistry as well as sediment characteristics of 25 springs were studied four times in 2003. The relationships between fauna composition and abiotic parameters were ascertained using multivariate statistical analyses. In total, fifty families or subfamilies and four higher taxa of invertebrates were identified in the springs studied. Only Gammarus fossarum (Amphipoda) occurred in all of the springs, whereas crenophilic taxonomic groups such as Turbellaria, Bythinellinae, Nemouridae, Limoniidae, Limnephilidae and Enchytraeidae as well as ubiquitous taxa such as Tubificidae and Chironomidae were very common but not present in all springs. Important factors determining differences in the taxonomic composition (at the family level) of the invertebrate fauna of springs were found to be those connected with their geographical location as well as chemical and discharge parameters, which were different for southern and northern groups of springs. The taxonomic richness, i.e. the number of invertebrate taxa, was found to be strongly dependent on discharge and the content of organic matter in bottom sediments, whereas specific taxa mentioned above had other abiotic determinants such as alkalinity, NO3 and temperature.