Age and site-specific pattern on encrustation of charophytes

Abstract

Encrustation and element content (Ca, Fe, K, Mg and P) of charophytes was studied along plant thalli to investigate the dependency of thallus age and site-specificity. Charophytes were collected from five sampling sites (Angersdorfer Teiche, Asche, Bruchwiesen, Krüselinsee and Lützlower See) which were distinct with respect to water chemistry. Furthermore, photosynthesis was measured to identify the physiological state of plants in habitat waters and with the addition of different ion concentrations (Ca2+, K+, Mg2+ and Na+). Age pattern on encrustation of charophytes was site-specific: carbonate content increased from the youngest to the oldest part (Angersdorfer Teiche), younger parts were less encrusted than older parts in Asche, Bruchwiesen and Krüselinsee, whereas encrustation in Lützlower See was the same along plants thallus. Charophytes showed species-specific encrustation in investigated sites. Encrustation of C. hispida in Angersdorfer Teiche was also as high as of individuals from hard-water lakes irrespective of 10.15 mS cm−1 (salinity of 6.3). For species growing in Angersdorfer Teiche, K/Na content and photosynthesis was lowest when compared to other sites. Photosynthesis of charophytes was enhanced after the addition of KCl and adversely affected by CaCl2, MgCl2 and NaCl. In summary, it was shown that encrustation of charophytes in water sites with strong ion anomalies could be as high as in hard-water lakes. It is assumed that ion composition, rather than ion concentration of Na+, Mg2+ and SO42−, impact on the encrustation of charophytes. The age pattern on encrustation in this study showed a strong site-specificity, whereas encrustation of charophytes was species-specific. Ion concentrations, either of habitats or actively added in laboratory measurements, impact on encrustation, element content and photosynthesis of charophytes.

Recycling and deposition of inorganic carbon from calcium carbonate encrustations of charophytes

“…Many studies have addressed charophyte calcification, including its mechanisms (e.g., McConnaughey and Falk 1991; McConnaughey and Whelan 1997; Sand‐Jensen et al 2018, 2021), the composition and amount of encrustation specific to species, thallus age, site and season. They frequently concluded that the encrusted calcium carbonate was finally deposited in lake sediments (e.g., Pukacz et al 2014 a , 2014 b , 2016; Herbst and Schubert 2018; Herbst et al 2018 a , 2018 b ). Our study shows that the fate of summer maximum encrustation is more complex than previously thought.…”

The Structure and Function of C4 Vascular Tissue

“…The location of isolated Kranz cells in this dicot is not unlike the location of isolated Kranz cells in Arundinella hirta. The isolated Kranz cells of the dicot, as might be expected, are arranged in clusters rather than parallel strands, however, and unlike the Arundinella cells, appear to be always associated with at least some vascular tissue (isolated veinlets), HERBST (1972) reports that these isolated veinleits "consist solely of tracheids, with no associated xylary parenchyma or phloem cells".…”

“…Before addressing this question, it may be productive to also consider an anatomical aberration in the dicot Euphorbia forbesii, reported to be a C 4 species (KRENZER et al 1975). HERBST (1972) noted that several species of Euphorbia (subspecies Chamaesyce which contains all the known C 4 Euphorbia) were characterized by numerous isolated disjunct veins that were surrounded by large parenchyma cells. Figure 5 is a paradermal view of a Euphorbia [orbesii leaf that was cleared and stained with 1 2K!.…”

“…In Euphorbia forbesii, there exists no prevalent separation of Kranz and vascular cells. Very little of the mesophyll is isolated from vascular bundle sheaths, because disjunct veinlets are contained within the Kranz cell 'islands' (HERBST 1972). From a functional standpoint, in fact, it is not clear whether the disjunct veins were differentiated in an attempt to accomodate the isolated Kranz cells, or if the disjunct veins were initiated independently, and Kranz cells smiply surrounded them in the normal manner.…”

Interactions between stoneworts (Charales) and waterbirds

“…This process has a decalcifying effect on surrounding water and, by precipitation of inorganic phosphorus incorporates this element and carbon into sediments, rendering them relatively inaccessible to biological activity (Murphy, Hall & Yesaki, 1983; Anderson & Ring, 1999; Rodrigo, Alonso‐Guillén & Soulié‐Märsche, 2009). There remains much to be understood about the biochemistry of these mineral encrustations, but they clearly depend on species, age and the ionic concentrations of the environment (Herbst & Schubert, 2018).…”