Bryophytes and heavy metals: a review

Abstract

Bryophytes, a group of terrestrial plants widely used in biomonitoring, are reviewed for their relation to heavy metals. In the present article, we summarized the knowledge on heavy metals pollution and accumulation effects on bryophytes. Mechanisms of tolerance and resistance are given as well.

Introductory Chapter: Bryophytes 2020

“…Many species occur on specific pH of the substrate, or indicate by appearance air quality. Additionally, some species are so well adapted to substrate and nutrients coming from dissolved substrate by precipitation that they can indicate the presence of salt (e.g., Entosthodon hungaricus) [9] or minerals (Pb, Ditrichum plumbicola; Cu, Scopelophila cataractae) [10] and are strict to such a region.…”

Moss species-specific accumulation of atmospheric deposition?

“…Substance inputs from the atmosphere into aquatic and terrestrial ecosystems are caused by falling or deposited precipitation ("wet/occult deposition") and/or by sedimentation and gas diffusion ("dry deposition"). In terrestrial ecosystems, such atmospheric deposition can be collected by technical facilities and accumulation bioindicators (also called: accumulation biomonitors) such as mosses for subsequent chemical element determination [16,25,27,39,40,44,50].…”

“…So far, only a few detailed interspecies and intra-species comparisons were carried out in mosses except for the common mosses mentioned above [32,53,55]. According to Stankovic et al [44], it can be assumed that different genotypes of the same species can also react differently to the accuracy and reliability of information obtained using mosses as biomonitors depend on the understanding of the mechanisms, factors and bryophyte species responses that can influence the uptake and the linearity of the relationship between dose and tissue content [2,3]. Therefore, studies in controlled conditions of axenic cultures are urgently needed for our better understanding of the relationship between bryophytes and heavy metals [44].…”

Accumulation of heavy metals in gametophytes of the epilithic mosses

“…Bryophytes, including mosses (representatives of Bryophyta division), have been recognized as bioindicators of environmental pollution and biomonitors of atmospheric deposition of heavy metals [11,18,19,21]. Owing to a number of morphological and physiological features, bryophytes are capable of absorbing heavy metals directly from air and precipitation, rather than from a substrate on which they grow.…”

“…Owing to a number of morphological and physiological features, bryophytes are capable of absorbing heavy metals directly from air and precipitation, rather than from a substrate on which they grow. In particular, these characteristics include: 1) lack of cuticle (or its very poor development) and internal vas cular system; 2) absence of a true root system; instead, the presence of unicellular rhi zoids for fixing to a substrate; 3) high accumulation capacity with respect to metals that are absorbed across the entire surface of plant [19,21]. By accumulating heavy metals in their tissues, bryophytes can thereby reflect the level of air contamination.…”