Micro-relief distribution of major mosses in ice-free areas along the Soya Coast, the Syowa Station area, East Antarctica

Micro-relief distribution of five major mosses, Pottia heimii, Ceratodon purpureus, Bryum pseudotriquetrum, Grimmia lawiana and Bryum argenteum, in the ice-free areas along the Soya Coast, continental part of East Antarctica have been compared. Those five mosses showed three different types of micro-relief distribution, at three different types of sites: mounds, slopes and hollows. Pottia heimii and Ceratodon purpureus prevailed on mound sites mixed with cyanobacteria. In dryer mound environments cyanobacteria was supposed to play an important role in nitrogen fixation. Bryum pseudotriquetrum and Grimmia lawiana dominated on hollow sites covered with sand. A more moisture rich condition of the hollow may promote their abundance associated with their high photosynthetic ability at moist sites. Bryum argenteum showed a rather unclear micro-relief distribution pattern. It appeared chiefly on mounds, but on hollows also. Rich nutrient input by sea birds into its habitats may allow various site selection under environments favorable to distribution

Structure and dynamics of the Ceratodon purpureus-Bryum pseudotriquetrum community in the Yukidori Valley, Langhovde, continental Antarctica

The structure and dynamics of the Ceratodon purpureus-Bryum pseudotriquetrum community along the Yukidori Valley, Langhovde near Syowa Station, continental Antarctica have been documented. This moss community showed a clear vegetation structure with a micro-relief distribution, consisting of three different sites; a mound, a slope and a hollow. On the hollow site a sand-covered Bryum pseudotriquetrum patch dominated. On the slope site a pure Ceratodon purpureus patch, a Bryum pseudotriquetrum patch, and a Ceratodon purpureus-Bryum pseudotriquetrum mixed patch abundantly occurred. On the mound site a cyanobacteria-mixed Ceratodon purpureus patch prevailed. The dynamics of this community was basically unclear. However, some change patterns were infered from the results. The sand-covered Bryum pseudotriquetrum patch and the cyanobacteria-mixed Ceratodon purpureus patch generally showed no clear change. It is also speculated that some of the patches of this community undergo cyclic changes. A suggested cyclic pattern is as follows; some of the sand-covered Bryum pseudotriquetrum patches turned on Ceratodon purpureus-Bryum pseudotriquetrum mixed patches, and finally those patches became a cyanobacteria-mixed Ceratodon purpureus patch. Some of them, on the other hand, degraded into sand-covered Bryum pseudotriquetrum patches, probably because of strong wind or water flow. However, more detailed studies will be needed to confirm these inferences

Reproductive phenology of subalpine moss, Polytrichum ohioense Ren. et Card.

The reproductive phenology of Polytrichum ohioense was investigated in a sub-alpine forest at the foot of Mt. Tyausu, in the Yatsugatake Mountains, Central Honshu, Japan. Shoots were collected every 2 weeks from May to October from the study site. Developmental stages of gametangia and sporophytes formed in the current and previous year were registered. The temperature above the turf occasionally dropped below 0℃ before June, while the temperature in the turf did not drop below 0℃. Juvenile antheridia formed about one month earlier than archegonia. Mature antheridia and archegonia are observed from late May to early August and from late June to mid-July, respectively. Fertilization seems to occur from late June to mid-July. Longer persistence of mature antheridia is supposed to contribute to higher efficiency of fertilization to supply its sperm for a relatively long period. And delayed formation of archegonia in the warm season may contribute to the adaptation to the temperature decrease at the beginning of the growing season. Sporophytes were found first at the end of June, then gradually grew and reached the ECI stage by October. The sporophytes seemed to spend the period of snow cover in the ECI stage, and started to grow again in the next growing season in May. Spore dispersal was observed from mid-July to mid-August. Sporophytes took 13 months to mature including a 6 month resting period. The phenological parameters observed in the present study provide a way to adapt to the the short growing season in the sub-alpine zone in Central Honshu, Japan

Ecological studies of aquatic moss pillars in Antarctic lakes 1. Macro structure and carbon, nitrogen and Chlorophyll a contents

Structures of a typical \u27moss pillar\u27 submerged in Antarctic lakes were investigated to analyze the sizes, age distribution, and composition such as shoot density, dry weight, carbon, nitrogen and chlorophyll a using a sample collected from lake B-4 Ike in the Skarvsnes region, East Antarctica. The moss pillar was mainly composed of shoots of a moss species, Leptobryum sp. Most of the green shoots of the species were located at the top surface of the pillar, and brownish old shoots with prominent vegetative diaspores, so-called rhizoidal tubers, formed the internal body of the pillar. The internal core of the pillar was nearly empty, and seemed to be decomposed considerably. Dry weight, carbon, nitrogen and chlorophyll distributions in the pillar took heterogeneous patterns, that is, they were largely centered at apical parts. It is suggested that growth of the moss pillar occurred extensively at the apical part. The age was estimated ca. 250 years at ca. 20 cm below the apical top by the AMS method. The presence of the moss pillar in lake B-4 Ike indicates that a tremendous amount of biomass has been produced under the oligotrophic freshwater Antarctic lake environment over more than a quarter millennium