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The effect of humidity change on spore release of the Nematodontae Polytrichaceae has never been tested experimentally. Similarly, the impact of humidity alterations on structure of the peristome have never been studied.Polytrichum commune Hedw. var. commune from Guizhou Province, China, was selected as the research object to examine effects of simulated wind in the laboratory. By controlling humidity and wind, the mechanism of spore dispersal was revealed.When humidity increased, the size of the peristome and epiphragm enlarged significantly (the peristome has no obvious spatial displacement, unlike the hygroscopic movement of Arthrodontae mosses. Thus, we named it 'sub‐hygroscopic movement'), then recovered to normal size when humidity decreased. When humidity was controlled and wind applied, the scattering of spores gradually decreased as the capsule dried out and finally reached a very low level; when the capsule was wetted or rewetted, the amount of spores released rose and returned to the initial state. Through comparison of moist and dry capsules, only enhanced humidity of the sporophytes led to increases in spore release.The results show that the dispersal of spores was significantly improved in windy conditions and the sub‐hygroscopic movement of the capsule peristome, which ensure the continuity and effectiveness of P. commune reproduction. [ABSTRACT FROM AUTHOR]

Slag produced in mining and smelting of manganese carbonate ore potentially pollutes the environment and endangers the health of humans and other living organisms.This study investigates the uptake of six heavy metals, Cu, Pb, Mn, Zn, Cr and Cd, by bryophytes and vascular plants growing on manganese carbonate slag in the Houshangou Slag Field near Zunyi City, Guizhou Province, China. Determination of heavy metal uptake in bryophytes and vascular plants may identify species suitable as biomonitors for bioremediation of polluted lands.Eight bryophyte taxa were identified in the study area; among which, Bryum argenteum and Physcomitrium eurystomum were dominant; life forms of bryophytes were predominantly short turfs. Three monocotyledons, all Poaceae, and five dicotyledons were recorded in four families. The highest heavy metal uptake in bryophytes, Mn content by B. argenteum, was more than 25,000 mg·kg−1. Furthermore, determination of heavy metal content in roots, leaves and fruits of six vascular plants demonstrated that each had a unique capacity for heavy metal accumulation: roots, leaves and fruits of similar plant species exhibited varying uptake capacity. Mn content in leaves was recorded in the order: B. davidii > A. tricolor > E. crus‐galli > C. argentea > P. acinosa > C. album.In summary, B. argenteum, Echinochloa crus‐galli and Phytolacca acinosa have strong enrichment capacity for heavy metals. These species could be used for comprehensive treatment of heavy metal pollution in electrolytic Mn slag fields, and for bioremediation of polluted areas associated with Mn mining and processing. [ABSTRACT FROM AUTHOR]

Bauxite mining on karst generates numerous ecological and environmental problems, including metal pollution, water and soil erosion and destruction of vegetation. Among these, the most important environmental problem is soil metal pollution. Higher plants have a great ability to adsorb metals and can be used as biological indicators. However, the study of bioindicators for soil contamination in karst bauxite is not clear.Plants and their soil were collected from an abandoned karst bauxite area at Shangdong, Guizhou Province, southwestern China. Plants were collected and identified as Pteris vittata, Pinus massoniana, Miscanthus floridulus, Coriaria nepalensis, Artemisia argyi and Senecio scandens.The content of metals in plant roots were in the order: P. vittata > M. floridulus > C. nepalensis, other plants roots had no consistent pattern. Concentrations of metal in plants (P. vittata and M. floridulus) and soil were: soil > root > leaf > stem. Levels of metals in soil samples easily exceeded background values, indicating that soil had been contaminated. Al and Fe were highest in soil samples of P. vittata, with a good correlation.Results show that the metal content determined in plants is relatively high, particularly in P. vittata. Data also suggest that P. vittata colonies were able to tolerate and accumulate high levels of metal elements, which evidences their suitability for use as bioindicatord of soil metal contamination caused by mining activities. [ABSTRACT FROM AUTHOR]

This review provides a summary of the published information on Guizhou liverworts and hornworts. Representing the first checkist of Guizhou for these groups, it includes all published names of taxa and their distribution up to 2004. A total of 246 specific and subspecific names in 67 genera and 32 families are included. Of these, 205 taxa are currently accepted taxa. [ABSTRACT FROM AUTHOR]