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

Which type of genetic disease can be identified, Which type of genetic dise...

Which type of genetic disease can be identified from the visual analysis of the number of chromosomes present in a karyotype? The counting and identification of chromosomes in

What are the organs that are part of the male genital system, Q. What are t...

Q. What are the organs that are part of the male genital system? The organs that comprise the male genital system are the testicles, the vas deferens, the seminal vesicles, the

Explain the process of transposition of the great arteries, Transposition o...

Transposition of the Great Arteries with VSD and Left Ventricular Outflow Tract Obstruction: The presence of such a condition has to be surgically corrected title is differenc

Carbohydrate metabolism, CARBOHYDRATE METABOLISM Carbohydrates  are  br...

CARBOHYDRATE METABOLISM Carbohydrates  are  broken down into  monosaccharides which are absorbed into  the  blood stream.  In  the  liver and muscles, most  of  the glucose  is

Reprouction, which hormone is secret in salivary gland?

which hormone is secret in salivary gland?

What happens to the tsh blood level in hypothyroidism, What happens to the ...

What happens to the TSH (thyroid-stimulating hormone) blood level in hypothyroidism? Why is there enlargement of the thyroid in the endemic goiter disease? When there is low T3

Single stranded conformation polymorphism analysis, This is a broadly used ...

This is a broadly used screening technique that find several genomic mutations in wide number of samples, this technique finds sequence variations because of point mutations or oth

Drinking & driving, DRINKING & DRIVING - It should not be mixed because...

DRINKING & DRIVING - It should not be mixed because alcohol - 1.       Impairs ability to judge distances. 2.       Reduces capacity to coordinate limb muscles. 3.

What are the two main species of taenias, What are the two main species of ...

What are the two main species of taenias that cause human diseases? The two major species of taenias that cause disease in humans are Taenia solium, or the pork tapeworm, and T

Gluconeogenesis, Gluconeogenesis Gluconeogenesis is the procedure throu...

Gluconeogenesis Gluconeogenesis is the procedure through that glucose is synthesized from smaller easier molecules such as lactate and pyruvate. Although the catabolic linear p

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