BOT3703 summaries
Chapter 1
Chapter 2
Chapter 3
Chapter 4
Chapter 6
Chapter 8
,THE NATURE OF QUANTITATIVE PLANT ECOLOGY AND VEGETATION SCIENCE
NATURE OF VEGETATION
Vegetation describes plant collectively or plant growth in mass
Plant ecology is a subdiscipline of ecology and biogeography
Field of quantitative ecology is related to an area of research known as vegetation science (vegetation
description and analysis, plant population biology, species strategies and vegetation dynamics)
Quantitative plant ecology and vegetation description and data analysis can and should be primarily
ecological rather than mathematical in emphasis. Only variations in vegetation and plant species
distributions can be properly understood and explained within an ecological framework
• Fundamental point that vegetation is always an integral part of an ecosystem that can only be
studied by fully exploring its role within that ecosystem
• Vegetation cannot be isolated as a sperate entity from the ecosystem it exists in
Building blocks of vegetation are individual plants. Its plant is classified according to a hierarchal system
of identification and nomenclature using carefully selected criteria of physiognomy and growth form
• Groups of individuals of a species forms a species population
• Groups of plant populations are known as plant communities/ plant species assemblages
• Within plant communities the presence/ absence of particular species is of primary importance
In most terrestrial habitats with the exception of hot and cold desserts, vegetation is the most obvious
physical representation of an ecosystem. Reasons that show the central importance of vegetation to
ecology and demonstrate the need for methods to assist with both description and data analysis:
1. Usually equate ecosystem types with different vegetation types and the dominant species
life-forms within them
2. Most vegetation is the result of primary production, net primary production (amount of
green plant tissue accumulated within the area of a particular vegetation type over a given
time period) represents the base of the trophic pyramid
3. Vegetation acts as the habitat within
,WHY STUDY VEGETATION?
Science of phytosociology, the mapping of vegetation communities and types, study of relationships
between plant species distributions, environmental controls, their interactions with humans and animals,
the study of vegetation as a habitat for animals
Information on vegetation may be required
a) Help to solve an ecological problem
b) For biological conservation and management purposes
c) An input to environmental impact statements
d) To monitor management practices
e) To provide the basis for prediction of possible future changes in plant species distributions and
linked to both human impacts on habitats via land use practices and also climate
Academic case, vegetation may be described and data analyzed for their own sake. Applied studies,
vegetation data is collected and analyzed with he aim of providing information of relevance to some
ecological problem.
THE SCIENTIFIC APPROACH
INDUCTION AND DEDUCTION
Collection and analysis of vegetation data provides the principal form of ecosystem description and
classification. An important concept is the idea of explanation “Why?”
There is always an existing body of knowledge and theory which is generally accepted at the time. Often
this initial body of knowledge has been collected by a process known as induction
• The data is collected without formulation of prior hypothesis or any preconceived ideas
• Explanations are then derived from the data collected
• Thought to be secure because the collection and ordering of facts for their own sake was not
based on any biased or selective guesses or hypothesis
Problems of this approach is the inefficient process of collecting a large amount of data that may not be
immediately or eventually relevant/ useful and which cannot ever prove a theory or hypothesis
, On the basis of existing knowledge and theory a scientific approach may often involve the generation
and testing of hypotheses concerning observed variations in vegetation cover and their causes. This is
usually known as deductive approach
• Commonly described as the scientific method
• Involves setting up both null and alternative hypothesis and if often also described as the null
hypothesis testing (NHT) approach
• Follows rational and logical sequence of through processes and actions
• Hypotheses are generated from the existing body if theory and data collection and analysis are
then based on the notion of accepting or rejecting the hypothesis
• Testing the hypothesis and proving them true (verification) or false (falsification) is central to
this process
Emphasis of scientific publications on proving hypotheses true rather than disproving them has led to the
notion of logical positivism
Chapter 1
Chapter 2
Chapter 3
Chapter 4
Chapter 6
Chapter 8
,THE NATURE OF QUANTITATIVE PLANT ECOLOGY AND VEGETATION SCIENCE
NATURE OF VEGETATION
Vegetation describes plant collectively or plant growth in mass
Plant ecology is a subdiscipline of ecology and biogeography
Field of quantitative ecology is related to an area of research known as vegetation science (vegetation
description and analysis, plant population biology, species strategies and vegetation dynamics)
Quantitative plant ecology and vegetation description and data analysis can and should be primarily
ecological rather than mathematical in emphasis. Only variations in vegetation and plant species
distributions can be properly understood and explained within an ecological framework
• Fundamental point that vegetation is always an integral part of an ecosystem that can only be
studied by fully exploring its role within that ecosystem
• Vegetation cannot be isolated as a sperate entity from the ecosystem it exists in
Building blocks of vegetation are individual plants. Its plant is classified according to a hierarchal system
of identification and nomenclature using carefully selected criteria of physiognomy and growth form
• Groups of individuals of a species forms a species population
• Groups of plant populations are known as plant communities/ plant species assemblages
• Within plant communities the presence/ absence of particular species is of primary importance
In most terrestrial habitats with the exception of hot and cold desserts, vegetation is the most obvious
physical representation of an ecosystem. Reasons that show the central importance of vegetation to
ecology and demonstrate the need for methods to assist with both description and data analysis:
1. Usually equate ecosystem types with different vegetation types and the dominant species
life-forms within them
2. Most vegetation is the result of primary production, net primary production (amount of
green plant tissue accumulated within the area of a particular vegetation type over a given
time period) represents the base of the trophic pyramid
3. Vegetation acts as the habitat within
,WHY STUDY VEGETATION?
Science of phytosociology, the mapping of vegetation communities and types, study of relationships
between plant species distributions, environmental controls, their interactions with humans and animals,
the study of vegetation as a habitat for animals
Information on vegetation may be required
a) Help to solve an ecological problem
b) For biological conservation and management purposes
c) An input to environmental impact statements
d) To monitor management practices
e) To provide the basis for prediction of possible future changes in plant species distributions and
linked to both human impacts on habitats via land use practices and also climate
Academic case, vegetation may be described and data analyzed for their own sake. Applied studies,
vegetation data is collected and analyzed with he aim of providing information of relevance to some
ecological problem.
THE SCIENTIFIC APPROACH
INDUCTION AND DEDUCTION
Collection and analysis of vegetation data provides the principal form of ecosystem description and
classification. An important concept is the idea of explanation “Why?”
There is always an existing body of knowledge and theory which is generally accepted at the time. Often
this initial body of knowledge has been collected by a process known as induction
• The data is collected without formulation of prior hypothesis or any preconceived ideas
• Explanations are then derived from the data collected
• Thought to be secure because the collection and ordering of facts for their own sake was not
based on any biased or selective guesses or hypothesis
Problems of this approach is the inefficient process of collecting a large amount of data that may not be
immediately or eventually relevant/ useful and which cannot ever prove a theory or hypothesis
, On the basis of existing knowledge and theory a scientific approach may often involve the generation
and testing of hypotheses concerning observed variations in vegetation cover and their causes. This is
usually known as deductive approach
• Commonly described as the scientific method
• Involves setting up both null and alternative hypothesis and if often also described as the null
hypothesis testing (NHT) approach
• Follows rational and logical sequence of through processes and actions
• Hypotheses are generated from the existing body if theory and data collection and analysis are
then based on the notion of accepting or rejecting the hypothesis
• Testing the hypothesis and proving them true (verification) or false (falsification) is central to
this process
Emphasis of scientific publications on proving hypotheses true rather than disproving them has led to the
notion of logical positivism
