Bryophyte Ecology in Northern Disturbed Ecosystems

点击翻译按钮获取中文摘要

Since graduate studies, my long term research program has been on the ecology of Sphagnum species in peatlands, first as impacted by acid rain (nitrogen deposition) and lately understanding their distribution and regeneration niche at early successional stages after disturbance. This will remain one main theme of my research programme but other groups of bryophytes such as brown mosses dominating fens and boreal pioneer upland bryophytes will also be studied. The general purpose of the research program will be to provide essential knowledge about what factors determine the success of establishment of mosses colonizing disturbed soils in peatlands (both for bogs and fens) or boreal and sub-arctic uplands. A focus of study will be on facilitation (how some plants benefit from growing in close association with neighbours) and how this plant-plant interaction relationship can contribute to theoritical plant ecology and improve our predictive ability of successional pathways. The program will also address how to use and benefit from mosses in ecosystem restoration based on an understanding of limiting factors in spontaneous and assisted colonization and succession. The effects of water level, nutrient availability, microtopography, shade, salinity, humidity and naphtenic acids on the establishment of mosses from spores and vegetative fragments will be studied. The main objectives will be to provide new knowledge of the factors controlling the dynamics of moss colonization of exposed soil, bare peat and rock surfaces in harsh environments. Specific habitats under study will be cut-over peatland with exposed organic soil across Canada (from Alberta to PEI), alpine disturbances in National Parks and sub-arctic disturbances For the taxa emphasis will be given to: 1) Sphagnum species colonizing fens and lagg zone, 2) Polytrichum and Dicranum genera, 3) species of the Amblystegiaceae common in fens as well as 4) Polytrichum piliferum, Niphotrichum canescens and the lichen Stereocaulon paschale.