Moss stage - xerarch, Biology

Assignment Help:

Moss Stage - Xerarch

The accumulation of soil, particularly in the crevices and depressions of rock favours the growth of certain xerophytic mosses, e.g., species of Polytrichum, Tortula and Grimmia. The spores of these mosses are brought by the blowing wind. They have more or less the same power of withstanding desiccation as that of foliose lichens.

The lichens and mosses grow together and compete 'with one another. The rhizoids of mosses and foliose lichens compete for water and nutrients, and the stems of the former attain greater height than the latter. The plants in the lower strata, i.e., the lichens die, and the mosses grow. The mosses form cushion-like structure that may be a few centimetres in thickness. The substratum is thus gradually built up and is widened. The foliose lichens gradually give way to mosses that overtop the lichens. Many times, all three stages may be found on a single rock surface, the pioneers occupying the most exposed places.


Related Discussions:- Moss stage - xerarch

Define the term price mechanism and its working, Define the term price mech...

Define the term price mechanism and how it works. The price mechanism and its working: The above demonstrated diagram assumes the market is into equilibrium, whereby deman

Define fluid and electrolytes requirements in elderly, Define Fluid and Ele...

Define Fluid and Electrolytes requirements in elderly? Care lo be taken that adequate fluid be given to the elderly. If patient is unable to take the required daily needs, then

Determine the use of natural colourants, Determine the use of natural colou...

Determine the use of natural colourants The use of natural colourants is limited due to their instability, low tinctorial power or price disadvantage.  The trend towards natura

Explain the structural and functional changes in cancer , Identify and brie...

Identify and briefly explain the structural and functional changes that occur in the large bowel when colorectal cancer develops.

Tanco beans, what is the origin, uses, morphology, active constituents and ...

what is the origin, uses, morphology, active constituents and market perparations ?

Cell, how does a cell work ?

how does a cell work ?

Ammonification, Ammonification Many heterotrophic bacteria actinomycet...

Ammonification Many heterotrophic bacteria actinomycetes and fungi in soil and water metabolise the organic nitrogen and release it in an inorganic form as ammonia. This proce

.phylum pisces, wt is an air bladder and its function wt is catadromous and...

wt is an air bladder and its function wt is catadromous and anadromus migration

Explain the meaning of life style modification, Explain the Meaning of Life...

Explain the Meaning of Life Style Modification Life Style Modification (LSM) is an important aspect in the treatment of diabetes. LSM will help the people who are pre-diabetic

Determine guidelines for planning balanced diets for elderly, Determine Gui...

Determine Guidelines for Planning Balanced Diets for Elderly? The key element in planning diets for the elderly should be nutrient-based dietary guidelines, in order to reduce

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd