Bryophyte communities and seston in a karst stream (Jankovac Stream, Papuk Nature Park, Croatia)

Abstract

<jats:p>An investigation into bryophyte communities in karst Jankovac Stream (Papuk Nature Park, Croatia) was carried out once a month from July 2008 to June 2009. Samples were taken from two lotic microhabitats: (i) Jankovac Spring (JS), a hypocrenal habitat with dense bryophyte clusters (90% bottom cover) and (ii) Jankovac Waterfall (JW), with scattered bryophyte clusters (50% bottom cover). At the same time, seston samples were collected during the spring as the source site and after the JW, as the outflow site. The goals of this study were to understand the (i) algal, protozoan and metazoan bryophyte community assemblages in these two lotic microhabitats, (ii) influence of environmental factors on the structuring of the bryophyte community and (iii) structure of seston along the longitudinal profile. A total of 172 taxa were determined: 68 algae, 55 protozoa, 24 meiofauna and 25 macroinvertebrates. Statistically significant differences between two microhabitats differing in percentage of bryophyte cover were established testing 13 environmental parameters. In dense bryophyte clusters, community structure was determined by flow velocity and pH, and macroinvertebrates achieved higher diversity and abundance. On the contrary, in scattered bryophyte coverage algae, protozoa and meiofauna reached higher abundance and diversity governed by the amount of suspended organic matter and epiphyton. In contrast to previous studies, the inverse ratio of community diversity and abundance<jats:italic>versus</jats:italic>percentage of bryophyte cover was established. We assume this to be the result of an enrichment of the scattered bryophyte clusters by upstream seston. Additionally, the effects of anthropogenic hydromorphological disturbance are reflected in macroinvertebrate diversity and abundance reduction.</jats:p>

Circadian (re)colonisation dynamics of macroinvertebrates in an isolated karst spring

“…Electrical conductivity was high, as expected in streams with limestone substrates that enrich the water with calcium and bicarbonate ions, 38,46 and values were similar in both open and closed canopy areas. Mean pH values were 0.1 higher in the open than closed canopy area.…”

“…14,28 Unlike previous research, a noticeably higher number of Diptera and Ephemeroptera was found in the present study. 38,46,48 Although the abundance of Baetidae and Chironomidae was very high in natural samples, they were much more abundant in artificial substrates, that is, they colonised artificial substrates very well. A good colonisation pattern in the open canopy area was also seen for Simuliidae individuals.…”

Submerged macrophytes as a habitat for zooplankton development in two reservoirs of a flow-through system (Papuk Nature Park, Croatia)

“…2007b; Sertic´Peric´et al, 2011). Moreover, in Jankovac Stream, lotic stretches are also covered with bryophyte, which is assumed to contribute to species diversity (Sˇpoljar et al, 2012).…”

Bridging community and metacommunity perspectives in benthic photosynthetic organisms (Serranía de Cuenca, Central Spain)

“…They are based on the collections of Arturo Caballero (first alone) and his daughter Francisca during the 1930s and 1940s when they both worked at the Real Jardín Botánico of Madrid (Álvarez Cobelas, 2020). Fortunately, the present contribution has been carried out in a limestone area of the Peninsula and there are some previous studies in limestone environments with which to compare our results (for example, those of Aboal, 1989Aboal, , 2006Sabater, 1989;Cantonati & Spitale, 2009;Špoljar et al, 2012;Ciorca et al, 2017).…”