Measuring biodiversity, Biology

Assignment Help:

Diversity is defined as the no of species present in a community termed as "species richness". We can represent species biodiversity at different geographical scales as alpha, beta and gamma diversity.

(a)         Alpha diversity: it indicates diversity within a particular area or ecosystem, and is usually  expressed by no of the species. Thus alpha diversity is measure of "species richness".

(b)         Beta diversity:  it refers  to the changes in species richness between ecosystem. The higher heterogeneity in the habitats in a region or greater dissimilarity between communities exhibit higher beta diversity.

Gamma diversity: it refers, to the diversity of the habitats over the total land scope or geographical area. The higher diversity at community levels provides stability and higher productivity. In temperate, grasslands, it has been observed that diverse communities are functionally more productive and stable, even under environment stresses such as prolonged dry conditions.

Extinction of species: A species is said to be extinct, when there is no reasonable doubt that its last individual has died.

The characteristic which make a species susceptible to extinction are listed below:

(i)                 Large body size eg. Elephant, lion and bengal.

(ii)               Small population size and low reproductive rate eg. Blue whale, giant panda.

(iii)             Feeding at high trophic levels in food chain eg. Bald eagle and bengal tiger.

(iv)              Fixed migratory routes and habitat eg. Blue whale and whooping crane.

(v)                Localized and narrow range distribution e.g. woodland caribou and island species.

Species become extinct by these three processes:

(i)                 Natural extinction

(ii)               Mass extinction

(iii)             Anthropogenic extinction

According to the world conservation monitoring centre (WCMC),533 animal (mostly vertebrates) and 384  plant species (mostly flowering plant) have become extinct since the year 1600.


Related Discussions:- Measuring biodiversity

Uses of drugs, USES OF DRUGS - 1.       Drugs are prescribed as medicin...

USES OF DRUGS - 1.       Drugs are prescribed as medicines to prevent or cure a variety of diseases. 2.       May be used to promot physical and mental health. 3.       U

What is metabolomics, Together, genomics, proteomics and transcriptomics ar...

Together, genomics, proteomics and transcriptomics are influential approaches to enhancing our understanding not only of how cells function normally but also what the key modificat

Explain both food and light as zeitgebers, Must account for both food AND l...

Must account for both food AND light as zeitgebers Because of the continuous light / dark periods of the year; light not always able to act as a zeitgeber. Food

Guidelines for diagnosis and treatment planning, Guidelines for diagnosis a...

Guidelines for diagnosis and treatment planning The diagnosis and planning the case is by far the most important step in the entire sequence of the treatment and due considerat

Excretory organs, Normal 0 false false false EN-IN X-...

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

Advantages and disadvantages of tissue valves, Advantages of Tissue Valv ...

Advantages of Tissue Valv es   Need for anticoagulation therapy is only for a short duration in xenograft and only there is rare need for anticoagulation therapy in au

List a few shortcomings of native starches, List a few shortcomings of nati...

List a few shortcomings of native starches which make it unacceptable in certain food applications. Lack of free-flowing properties of water repellence of the starch granules,

Homework, The Waldorf family was caught in a fire but escaped. Unfortunatel...

The Waldorf family was caught in a fire but escaped. Unfortunately, the father and daughter suffered burns. The father had second-degree burns on his entire chest, abdomen, and bot

What is the defense mechanism to stop an infection, What is the defense mec...

What is the defense mechanism that begins to work when inflammation fails to stop an infection? If the inflammatory attack is not enough to halt the infectious process the body

What are the major cells of which poriferans are made, Q What are the major...

Q What are the major cells of which poriferans are made? Sponges have their external wall covered by flat cells called pinacocytes and having pores well-delimited by special ce

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