GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Climatic and environmental gradients  (1)
  • Response surfaces  (1)
Document type
Keywords
Publisher
Years
  • 1
    ISSN: 1573-5052
    Keywords: Bryophytes ; Climatic and environmental gradients ; DCCA ; Peatlands
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Climate is a major factor affecting the development and form of peatlands, as well as the distribution of individual bryophyte species. This paper examines the climatic and ecological gradients affecting the distribution of peatland types along a north-south gradient in the Mackenzie River Basin. Based on a TWINSPAN analysis of bryophyte abundance from 82 peatlands in the Mackenzie River Basin, seven peatland types, two with southerly geographical distributions are recognized. In the Mackenzie River Basin, such local factors as surface water chemistry, pH, and solute concentration as well as height above the water table play a significant role in determinining bryophyte species distributions. Climate is secondary. Amongst the climatic variables, precipitation, length of the growing season, and annual temperature are the most signifcant. The seven peatland groups are: widespread poor fens; peat plateaus with thermokarst pools, low-Boreal bogs; bogs and peat plateus without thermokarst pools; low-Boreal dry poor fens; wet moderate-rich fens; and wet extreme-rich fens.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Plant ecology 93 (1991), S. 29-45 
    ISSN: 1573-5052
    Keywords: Bryophyte ; Response surfaces ; Peatlands ; Western Canada ; Sphagnum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Bivariate response surfaces were fitted to abundance data for 6 mire bryophyte species in ecological and climatic space in western Canada. Response surfaces were derived by gridding data, eliminating outliers, and reducing effects of overly influential abundance values. Predicted values at each grid node were calculated as distance-weighted means of all observed values within a predetermined radius of each node. Response surfaces accurately delimited species ecological and climatic ranges. The gridding process consistently underestimated observed abundance values, and paired t-tests indicated significant differences between predicted and observed values for Sphagnum fuscum and Tomenthypnum nitens in ecological space, and for Sphagnum fuscum, Tomenthypnum nitens, and Scorpidium scorpioides in climatic space. Predicted values were significantly different only for those species that had large data sets, and for species that had clusters of points with an inordinately large number of data points within them. However, with the exception of Sphagnum tenellum, predicted and observed values were significantly correlated for all species in both ecological and climatic space. R 2 analyses for the linear relationship between predicted and observed values can be used as a diagnostic tool to determine the effectiveness of the gridding process to accurately predict observed abundance values.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...