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Mosses are the pioneer and the first green land plants developed during the evolutionary process, they play an important role in the development of soil, biogeochemical cycling and facilitating plant colonization. Although species richness, composition, diversity and cover of moss communities vary, they grow well almost in all forests. Why mosses can grow in different conditions? What are the adaptive strategies of mosses in different forests along primary succession sequences? It is not still completely clear. In order to answer these questions, nutrient and carbohydrate accumulation in mosses were tested along the primary succession following deglaciation of Hailuogou glacier, Gongga Mountain, China. Nitrogen (N), phosphorus (P), potassium (K) content, total organic carbon (TOC), soluble sugar and starch accumulated in the dominant moss species were determined and compared. TOC increased insignificantly with forest age. N, P, K contents in mosses were significantly higher in forests with dense shrubs, where N content was seperately 1.69% in A. hookeri and 1.35% in P. schreberi in 30 yr aged forest, P content in 30 yr and 52 yr aged forest was seperately 0.022% and 0.020% in A. hookeri and 0.020% and 0.017% in P. schreberi, and K content in 30 yr and 52 yr aged forest was seperately 0.570% and 0.553% in A. hookeri and 0.490% and 0.493% in P. schreberi. Soluble sugar was higher in the early stage of succession, but the opposite was observed for starch and nonstructure carbohydrate content, which was lower in early successional stage. Mosses adopted different adaptive strategies in different aged forests along receding glacier, in which starch and N, P, K contents were key for adaptiation. That is, mosses accumulated much more starch in the severe environment of early succession stage. In more favourable environment, N, P, K was found to be accumulated for plant growth.
Crinoid genus Ammonicrinus is represented by two species, A. sulcatus Kongiel and A. kongieli sp.n., in the Grzegorzowice - Skały and Świętomarz - Śniadka profiles of the Middle Devonian in the Holy Cross Mts. The presence of barrel-like columnals of a limited mobility in distal part of stems and the development of wide tuberculated external cover indicate that both species represent sessile benthos. In A. sulcatus stem was connected with crown through modified columnalium. The crown was equipped with short arms which could take food in a space limited to the interior of coiled part of the stem. The food was supplied by current parallel to the bottom. The structure of crown and stem suggests that all Ammonicrinus species represent the same evolutionary stage.
A description of the morphology and evolution of a group of Upper Silurian monograptids, suggested to constitute Neocucullograptinae n. subfam., and including Bohemograptus Přib., Neolobograptus n. gen. and Neocucullograptus n. gen. is given. Studies were based on material etched from the core of Mielnik on the Bug (Eastern Poland) deep boring, and partly on erratic boulders of Baltic origin. In Lower Ludlovian Neocucullograptinae n. subfam. were represented by Bohemograptus, which on the boundary with Upper Ludlovian acquired the capability to produce microfusellar tissue. Further evolution of Neocucullograptinae n. subfam. marked by appearance of specialized representatives of Upper Ludlovian Bohemograptus, Neolobograptus n. gen. and Neocucullograptus n. gen., was closely connected with the utilisation of this peridermal fabric. Last named forms constitute characteristic elements of graptolite fauna in the Siedlce Beds of the Polish Platformian Silurian, which enable subdivision of their lower member into 5 new graptolite zones. Occurrence of this fauna on other areas of Eastern and Central Europe is indicated. Nature of changes in graptolite fauna on the boundary of Lower and Upper Ludlovian is discussed, and the probable role of biotic factors in extinction of Graptoloidea is emphasized. Origin and tentative phylogeny of Neocucullograptinae n. subfam. are discussed and probable biological interpretation of observed changes suggested. Quantitative analysis of long-lasted Bohemograptus bohemicus (Barr.) lineage has been given, and on the base of available evidence, a discrimination of two temporal subspecies is substantiated. Eight representatives (species and subspecies) of the Neocucullograptinae n. subfam. are described in systematic part. Three species and one subspecies are new. Moreover, appendix comprises description of two new aberrant species of "Monograptus".
Ultrastructure of microfusellar tissues has been studied in Neocucullograptus kozlowskii, and compared with that in normal fuselli. Microfusellar tissue is composed of both fully developed and reduced microfuselli. The former consists of the fusellar and the cortical components and may pass into reduced microfuselli due to skipping the fusellar phase of secretion. This demonstrates a possible mechanism of the transition from the fusellar to the cortical tissue and sheds some light on principles governing the morphogenesis of graptolite skeletal tissues. Formation of particular fabrics and patterns was determined by control of a certain innate potential of secretory cells. Modes of changes in this control are identified and a working hypothesis concerning the evolution of graptolite skeletal tissues is advanced.
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