Odum's 24 Attributes of Succession

Here is the table of Odum's 24 Attributes of ecological succession. It is from Science, New Series, Vol. 164, No. 3877. (Apr. 18, 1969), pp. 262-270. For the full article you can click this link.

To see a larger image click on the picture.

Hydrosere and Xerosere – Ecological Succession

Hydrosere
Hydrosere or Hydrarch succession occurs in a pond and its community are converted into a land community.

Characteristics of Hydrosere:

• In the initial stage, phytoplankton(cyanobacteria), green algae (Spirogyra,Oedogonium) are the pioneer colonizers.
• They are consumed by zooplankton (protozoans asAmoeba, Euglena, Paramecium etc), fish such as sun fish, blue gill fish etc.
• Gradually these organisms die and increase the content of dead organic matter in the pond.
• This is then utilized by bacteria and fungi, and minerals are released after decomposition.
• Nutrient rich mud supports rooted hydrophytes growth as Elodea, Hydrilla, Ceratophyllum etc in the shallow water zone.
• This submerged stage is also inhabited by animals such as may flies. Dragon flies etc and Crustaceans asDaphnia, Cypris, Cyclops etc.
• The hydrophytes die and decomposed by micro organisms and thus release nutrients.
• Due to silting, water depth is  reduced and at the margin of pond grow rooted floating vegetation.
• Example- Nelumbo nucifera, Monochoria, Trapa etc.
• In floating stage faunal living space is increased and diversified. Example- frogs, salamander, hydra,  diving beetles etc inhabit such conditions. Some turtles and snake also invade the pond.
• Gradually, the water depth decreases due to water evaporation and organic matter decomposition.
• Free floating plants as Lemna, Azolla, Pistia, Spirodella, Wolffia etc increase in number as availability of high nutrient is there.
• When these die, they build up the pond ecosystem, resulting in further build up of the substratum.
• Pond becomes a Swampy ecosystem.
• The reed swamp species, such as Scirpus, Typha or Phragmites and sedges as Juncus, Carex, Cyperus etc invade the pond and gradually replaced by mesic communities.
• Gradually, land plants as shrubs (Salix and Cornus) and trees (Almus, Populus) invade ending in the climax community as deciduous forest.
• The aquatic fauna also changes and ultimately gets replaced by land animals.

Xerosere
Xerosere or Xerarch succession begins on  exposed parent rocks (lithosere) or dry sand (psammosere).
A lithosere involves following stages-

crustose lichen stage (pioneers) – foliose lichen stage – moss stage – herbs stage – shrub stage – forest stage (climax stage).

Characteristics of Xerosere:

• Thus, pioneer plants are lichens, mosses and Selaginella that help in soil formation.
• In due course of time, annuals and herbaceous vegetation grow on the soils deposited on rocks.
• Lithosere also involves successive changes in animal life.
• Pioneer stages in animals are few species of mites, spiders and ants which are exposed to harsh temperatures.
• During moss stage, many new species of mites, spiders, springtails invade the community.
• Herb stage is invaded by nematodes, mites and various insect larvae.
• Great modifications occur in  the fauna of shrub and forest stage. Numerous kinds of animals as snails, wire worm, millipede, mites, ants and amphibians such as frogs, salamander occur. Reptiles which occur there are skinks, turtles and other lizards. Birds such as grouse and flycatcher and mammals as shrews, mouse, mole, squirrels, fox and chipmunk occur.

Websites:

http://apbiology.ygoy.com/236/hydrosere-and-xerosere-ecological-succession/

http://en.wikipedia.org/wiki/Xerosere

http://en.wikipedia.org/wiki/Hydrosere

Forest Assignment

Here are some websites for the forest assignment...

http://www.indianetzone.com/2/indian_forests.htm
http://www.onestopias.com/ias-articles/indian-forest-services/details/types-of-forests-in-india-98.asp
http://en.wikipedia.org/wiki/Tropical_Rainforest_of_India

Click on the photo to see it bigger.
More more photos click here.

Table 10-1 Primary Production for the World

Here is the table the Ghoshal Madam wanted us to see. Click on the photo to make it bigger.

r- and K- Strategies Table

Singh Sir had told us to to create a table about r- and K- strategies. Here is one I found from http://pespmc1.vub.ac.be/papers/r-KselectionQOL.pdf. It is taken from Pianka and Wilson.

Table 1 summarizes the typical differences between organisms that follow either type of strategies [cf. Pianka, 1970; Wilson, 1975].

r-organisms	K-organisms
short-lived	long-lived
small	large
weak, vulnerable	robust, well-protected
fast maturation	slow maturation
prone to take risks	risk averse
opportunistic exploiters	consistent exploiters
less intelligent, experienced...	more intelligent, experienced...
strong sex drive	weak sex drive
reproduce at an early age	reproduce at a late age
large number of offspring	small number of offspring
small relative size at birth	large relative size at birth
little care for offspring	much care for offspring
variable population size	stable population size

Table 1: typical differences between organisms that follow r-strategies (e.g. rabbits, sparrows), respectively K-strategies (e.g. elephants, parrots)

Singh, Singh, Gupta: Ecology, Environment & Resource Conservation

Are you having trouble following our Ecology class? This book was recommended by our seniors. They said it was very helpful.

It is available in our department library. Also available to buy in photocopy form in Lanka. It is not available at Student Friends bookstore nor University bookstore in Lanka.

This book has some good topics in it, for example:

• Defining Ecology
• Characteristics of Population
• Life History Strategies, r- and k- selection
• Niche
• Ecological Succession
• Ecosystem Structure, Function and Processes
• Food Chain and Food Webs
• Ecosystems Nutrient Cycling

Description of the book:

Ecology,Environment & Resource Conservation
Singh, J.S., Singh, S.P. & Gupta, S.R.

This is the first comprehensive textbook of its kind on ecology and environment published in India by three leading ecologists. Every post-graduate student of ecology must have a personal copy.

Over the year, the scope of our scientific understanding and technical skills in ecology and environmental science have widened significantly, with increasingly greater emphasis on societal issues. In this book an attempt has been made to give basic concepts of ecology, environmental science and various aspects of natural resources.

ISBN:		8188342556		List Price:		INR 595.00
ISBN-13:		9788188342556		Sale Price:		INR 595.00
Publisher:		Anamaya Publishers		Pages:		688
				Language:		English

Links for the book:

• Book Release
  http://www.nieindia.org/news_archive.asp
• Book Review
  http://www.nieindia.org/downloads/bookrev_ecology-singh-et-all.pdf
• Buy Book Online
  http://www.a1books.co.in/ecology-environment-resource-conservation/itemdetail/8188342556/