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

What is the function of the left ventricle, Q. What is the function of the ...

Q. What is the function of the left ventricle? Where does the blood go after leaving the left ventricle? The function of the left ventricle is to pump the blood under high pres

Give the genotypes, Achondroplasia is an autosomal dominant disorder associ...

Achondroplasia is an autosomal dominant disorder associated with a gene on chromosome 4. Sickle cell anemia is due to a gene on chromosome 11. A man and a woman with achondroplasia

Explain procedure for analysis of air of processing facility, Explain Proce...

Explain Procedure for Analysis of Air of Processing Facility? Now conduct the experiment following the steps enumerated herewith: 1. Label the Petri plates with nutrient aga

Coordination and control, how is an increase in glucose concentration contr...

how is an increase in glucose concentration controlled in the human body?

Excretion, What is the excretion for agamalizard

What is the excretion for agamalizard

Write the blood sugar in normal range and range in diabetes, Q. Write the b...

Q. Write the blood sugar in normal range and range in diabetes? Normal           Diabetes mellitus >126 mg / dl >200 mg / dl

#titlenergye.., Ask queson #Minimum 100 words accepted#sources of fuel whic...

Ask queson #Minimum 100 words accepted#sources of fuel which do not depend on fossil fuel

How the body gets rid of dust which enters the lungs, Using the words 'cili...

Using the words 'cilia' and 'mucus', describe, very briefly, how the body gets rid of dust which enters the lungs. The lining of the air passages makes mucus which traps dust p

What is the notochord, What is the notochord? How is this structure formed?...

What is the notochord? How is this structure formed? The notochord is a rodlike structure that produces the supporting axis of the embryo and gives birth to the vertebral colum

Explain the treatment of susceptible tb, Treatment of susceptible tb Al...

Treatment of susceptible tb All isolates of Mycobacterium tuberculosis should be tested for antimicrobial susceptibility, but results generally do not become available for at l

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