Phytogeography is concerned with all aspects of plant distribution, from the controls on the distribution of individual species ranges to the factors that govern the composition of entire communities and floras.
Vascular Cambium & Seasonal activity & its Role in Stem & RootFatima Ramay
Vascular Cambium & Seasonal activity & its Role in Stem & Root:
The vascular cambium (pl. cambia or cambiums) is a lateral meristem in the vascular tissue of plants.
The vascular cambium is a cylindrical layer of cambium that runs through the stem of a plant that undergoes secondary growth.
In Dicots:
The vascular cambium is in dicot stems and roots, located between the xylem and the phloem in the stem and root of a vascular plant, and is the source of both the secondary xylem growth (inwards, towards the pith) and the secondary phloem growth (outwards).
In Monocots:
Monocot stems, such as corn, palms and bamboos, do not have a vascular cambium and do not exhibit secondary growth by the production of concentric annual rings. They cannot increase in girth by adding lateral layers of cells as in conifers and woody dicots.
Cambium of some plants remains active for the entire period of their life, i.e., cambial cells divide and resulting cells mature to form xylem and phloem elements.
This type of seasonal activity usually found in the plants present in the tropical regions, and not all plants show cambial activity.
Percentage of ringless trees in the rain forests of; India : 75% Amazon : 43% Malaysia : 15%
In regions with definite seasonal climate; seasonal activity of cambium ceased with onset of unfavorable conditions; In Autumn, it enters the dormant state and lasts for the end of summer; In Spring, cambium again becomes active.
Duration of cambial activity is also affected by day-length, e.g., In Robinia pseudoacacia, cambium is dormant under short-day condition.
The cambium cells formed in circular in cross section from the beginning onwards.
The cambial ring is partially primary (fascicular cambium) and partially secondary (interfascicular cambium).
Periderm originates from the cortical cells (extra stelar in origin).
In Dicot stem, for mechanical support xylem is with comparatively smaller vessels, greater fibers and less parenchyma.
More amount of cork is produces for protection.
Lenticels on periderm are very prominent.
The cambial ring formed is wavy in the beginning and later becomes circular.
The cambium ring is completely secondary in origin.
Periderm originates from the pericycle (intra stelar in origin).
In Dicot root, xylem is with big thin walled vessels with few fibers and more parenchyma.
Less amount of cork is produced as root is underground.
Lenticels on periderm are not very prominent.
Phytogeography is concerned with all aspects of plant distribution, from the controls on the distribution of individual species ranges to the factors that govern the composition of entire communities and floras.
Vascular Cambium & Seasonal activity & its Role in Stem & RootFatima Ramay
Vascular Cambium & Seasonal activity & its Role in Stem & Root:
The vascular cambium (pl. cambia or cambiums) is a lateral meristem in the vascular tissue of plants.
The vascular cambium is a cylindrical layer of cambium that runs through the stem of a plant that undergoes secondary growth.
In Dicots:
The vascular cambium is in dicot stems and roots, located between the xylem and the phloem in the stem and root of a vascular plant, and is the source of both the secondary xylem growth (inwards, towards the pith) and the secondary phloem growth (outwards).
In Monocots:
Monocot stems, such as corn, palms and bamboos, do not have a vascular cambium and do not exhibit secondary growth by the production of concentric annual rings. They cannot increase in girth by adding lateral layers of cells as in conifers and woody dicots.
Cambium of some plants remains active for the entire period of their life, i.e., cambial cells divide and resulting cells mature to form xylem and phloem elements.
This type of seasonal activity usually found in the plants present in the tropical regions, and not all plants show cambial activity.
Percentage of ringless trees in the rain forests of; India : 75% Amazon : 43% Malaysia : 15%
In regions with definite seasonal climate; seasonal activity of cambium ceased with onset of unfavorable conditions; In Autumn, it enters the dormant state and lasts for the end of summer; In Spring, cambium again becomes active.
Duration of cambial activity is also affected by day-length, e.g., In Robinia pseudoacacia, cambium is dormant under short-day condition.
The cambium cells formed in circular in cross section from the beginning onwards.
The cambial ring is partially primary (fascicular cambium) and partially secondary (interfascicular cambium).
Periderm originates from the cortical cells (extra stelar in origin).
In Dicot stem, for mechanical support xylem is with comparatively smaller vessels, greater fibers and less parenchyma.
More amount of cork is produces for protection.
Lenticels on periderm are very prominent.
The cambial ring formed is wavy in the beginning and later becomes circular.
The cambium ring is completely secondary in origin.
Periderm originates from the pericycle (intra stelar in origin).
In Dicot root, xylem is with big thin walled vessels with few fibers and more parenchyma.
Less amount of cork is produced as root is underground.
Lenticels on periderm are not very prominent.
economic importance of gymnosperms.Gymnosperms are simple and primitive seed-bearing plants without flowers.
The plant body is sporophytic and is differentiated into root,stem and leaves.
All gymnosperms are usually wind-pollinated.
Leaves have thick cuticle and sunken stomata.
Gymnosperms are heterosporous.magasporangia and microsporangia occur on mega and microsporophylls respectively.
Ecades and ecotype - Ecades •introduction •Definition •Explanation •types of ecades , Ecotype, • introduction, •Definition ,•Ecotype VS. species ,•How did ecotype appear ,•From ecotype to species, •Example
This PPT explains about the various methods and steps of preparation of herbarium specimens. It also describes the various functions performed by herbaria and the various major herbaria of world as well as in India.
This presentation was given by Dr. Avishek Bhattacharjee in Botanical Nomenclature Course held in Botanical Survey of India, Eastern Regional Centre, Shillong in November 2016. This may be helpful to the undergraduate and post graduate Botany students to understand different types of taxonomic literature, especially Flora, Revision and Monograph.
This is an excerpt of basic concepts and principles of palynology as it applies to systematics and taxonomy of plants. Credits are given to the authors and owners of photographs used in the entire presentation.
economic importance of gymnosperms.Gymnosperms are simple and primitive seed-bearing plants without flowers.
The plant body is sporophytic and is differentiated into root,stem and leaves.
All gymnosperms are usually wind-pollinated.
Leaves have thick cuticle and sunken stomata.
Gymnosperms are heterosporous.magasporangia and microsporangia occur on mega and microsporophylls respectively.
Ecades and ecotype - Ecades •introduction •Definition •Explanation •types of ecades , Ecotype, • introduction, •Definition ,•Ecotype VS. species ,•How did ecotype appear ,•From ecotype to species, •Example
This PPT explains about the various methods and steps of preparation of herbarium specimens. It also describes the various functions performed by herbaria and the various major herbaria of world as well as in India.
This presentation was given by Dr. Avishek Bhattacharjee in Botanical Nomenclature Course held in Botanical Survey of India, Eastern Regional Centre, Shillong in November 2016. This may be helpful to the undergraduate and post graduate Botany students to understand different types of taxonomic literature, especially Flora, Revision and Monograph.
This is an excerpt of basic concepts and principles of palynology as it applies to systematics and taxonomy of plants. Credits are given to the authors and owners of photographs used in the entire presentation.
In this ppt, you will study about the different biographical zone of India and types of forest in India and about Indian Biodiversity with a video made by me on youtube. you can follow me here and you can see my more video on youtube.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
3. Phytogeographical regions of India
• Western Himalayas
• Eastern Himalayas
• Indus plains
• Gangetic plains
• Central India
• Deccan
• Western Coast of Malabar
• Assam
• Bay Islands of Andaman and Nicobar
4. 1) Western Himalayas
• Northern India – highest range of Himalayas
• Climate and vegetation – truly tropical at low altitude and temperate arctic
type at high altitude
• Northern mountain – western, central and eastern zones
• Western Himalayas – North and South Kashmir, a part of Punjab
• Rainfall – 100 to 200 cm annually
• Snowfall during winter
• Divided into 3 subzones:
• i) Submontane zone – up to 1500 m altitude –Shivalik area – Shorea robusta
• ii) Temperate zone – from 1500 m t0 3500 m altitude – oaks are dominant
• iii) Alpine zone – above 3500 m up to snowline – dominated by conifers
5. 2) Eastern Himalayas
• Extend from Sikkim to upper Assam, Darjeeling
• Divided into:
• i) Tropical submontane zone – warm humid climate – extend up to altitude of
1800 m – Sal forest
• ii) Temperate or montane zone – upper temperate zone (3000-4000 m –
conifers and Rhododendron, lower temperate zone (1800-3000 m – Oaks,
Michelia)
• iii) Alpine zone – 4000 m up to snowline – absence of trees – dominated by
shrubs and meadows – Rhododendron and Juniper
• Considered to be richest vegetational units in the world consisting of foreign
plant species
6.
7.
8. 3) Indus Plains
• Includes part of Punjab, Rajasthan, Kutch,
Delhi and Gujarat
• Characterized by dry hot summer and dry
cold winter
• Rainfall – 70 cm, in some regions – 10-15
cm
• Soil is saline
• Some parts have become desert due to
excessive dryness
• Vegetation – bushy and thorny
• Acacia arabica, Salvadora are common
9. 4) Gangetic Plains
• One of the richest vegetational zones in India
• Part of Delhi, whole of UP, Bihar, West Bengal and part of Orissa
• Rainfall – 50 to 150 cm
• Most land under cultivation
• Crop plants – wheat, barley, maize, jowar, bajra, urad, moong, sugarcane, pea,
potato, rice
10. 5) Central India
• Covers MP, Chhatisgarh, part of Orissa, Gujarat
• Hilly area
• Rainfall – 100-170 cm
• Some places are at high altitude – 500 -700 m
• Teak trees are common
• Divided into:
• i) Sal forest
• ii) mixed deciduous forest
• iii) thorny forest
11. 6) Deccan
• Whole of Southern peninsular India
including Satpura and Southern part of
Godawari river
• Rainfall – 100 cm
• Divided into:
• i) Deccan plateau – teak forest, Acacia,
Santalum album
• ii) Coromandel coast – halophytic
species
12. 7) Western Coast of Malabar
• Small botanical region – Cape Comorin to
Gujarat and Western Ghat
• Region of heavy rainfall
• 4 types of forests:
• i) Tropical forests – 700 m altitude – tall trees,
root buttresses – Artocarpus hirsuta
• ii) Mixed deciduous forests – 1600 m –
Terminalia spp., teak, bamboo
• iii) Temperate evergreen forests (sholas) –
above 1200 m – Gardenia robtusa, Michelia
nilgirica
• iv) Mangrove vegetation – west coast of
Malabar region – high rainfall
13. 8) Assam
• Rich in vegetation
• Covers valley of Brahmaputra, Naga
hills and Manipur
• Heavy rainfall
• Cherrapunji – one of the rainiest
places in world – 1000 cm rainfall
• Ficus, Artocarpus, Michelia
• Orchids and ferns are rich in this
region
14. 9) Bay Islands of Andaman and Nicobar
• Represent elevated portions of submarine
mountains
• Humid climate
• In Andaman – beech forest, evergreen
forest, semi-evergreen forest, deciduous
forest and mangrove forest
• Rhizophora, Mimusops are common
• Some part is under cultivation – rice and
sugarcane
15. References
• Shukla JP, Pandey A and Pandey K. 2009. Environmental
Biology and Ecology. Narendra Publishing House. 178- 205.
