Herb stage - xerarch, Biology

Assignment Help:

Herb Stage - Xerarch

The Soil-forming and soil-holding reactions of the mosses are so pronounced that the seeds of various xerophytic herbs, especially short-lived annuals: are soon able to germinate and grow. The plants mature, although the first generations, because of the drought and sterility of the soil, may make only a stunted growth. Their roots continue the process of corroding the rock, and each year the humus from their decaying remains enriches the soil. Gradually, biennials and perennials begin to invade the area and with the habitat becoming more and more favourable, their numbers also increase.

The processes of rock disintegration and humus and nutrient accumulations are greatly increased, as the tangled network of roots increases and the soil becomes shaded. Evaporation and temperature extremes are decreased, humidity is slightly increased, and drought periods are shortened. The bacterial, fungal and animal populations of the soil increase and conditions gradually become less xeric. Up to now, some xerophilous, shallow rooted grasses like Aristida, Festuca and Poa were growing. As the conditions improve, then some drought-enduring species like Potentilla, Solidago and many others invade the area. As a result of growth of the herbs, the smaller plants like mosses and lichens do not get enough light. So these conditions are detrimental for their growth, they gradually start perishing.


Related Discussions:- Herb stage - xerarch

Explain diffrent type of mycotoxins, Q. Explain diffrent type of Mycotoxins...

Q. Explain diffrent type of Mycotoxins? Mycotoxins are secondary metabolites produced by molds on foodstuffs that cause illness or death when ingested by man or animals. The pr

Explain about tropical rain forests, Q. Explain about Tropical Rain Forests...

Q. Explain about Tropical Rain Forests? As you approach the equator the climate becomes increasingly hot and seasonal variation in climate decreases resulting in practically th

Peste des petits ruminants (ppr), Peste des petits ruminants (PPR) is an a...

Peste des petits ruminants (PPR) is an acute, highly contagious viral disease of goats and sheep caused by peste des petits ruminants (PPR) virus which belongs to the genus Morbil

Alkoloids, what do you mean by alkoloids how are they usedin daily life wha...

what do you mean by alkoloids how are they usedin daily life what are the different types of alkoloids?

Explain venous thromboembolism, Venous Thromboembolism Prolonged immob...

Venous Thromboembolism Prolonged immobilization (>8 hours) increases the risk of lower extremity deep vein thrombosis (DVT), particularly in travelers with risk factors for th

Efficiency of feed utilization on complete feeds, Efficiency of feed utiliz...

Efficiency of feed utilization on complete feeds The complete diet concept is based on group rather than individual feeding and usually involves much fewer changes in diet for

Ecology, Types of survivorship curves

Types of survivorship curves

Lab report, Why making a smoke print of a leaf

Why making a smoke print of a leaf

Uses of microbes in industry-citric acid, Normal 0 false fals...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Explain ozone shield, Explain ozone shield? Name two gases that can ca...

Explain ozone shield? Name two gases that can cause damage to this shield. Give one harmful effect of this damage each on plants and animals.

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