biodiversity conservation
TRANSCRIPT
Introduction:In our biosphere immense diversity
(or heterogeneity) exists not only at the species level but at all levels of biological organization ranging fro macromolecules within cells tobiomes
(i) Genetic diversity(ii) Species diversity(iii) Ecological diversity
Species diversity
Patterns of Biodiversity :
(i) Latitudinal gradients
(ii) Species-Area relationships
Loss of Biodiversity
loss of biodiversity in a region may lead to
(a) decline implant production,
(b) lowered resistance to environmental perturbations such as drought and
(c) increased variability in certain ecosystem processes such as plant productivity, water use, and pest and disease cycles.
Causes of biodiversity losses:The accelerated rates of species
extinctions that the world is facing now are largely due to human activities. There are four major causes
(i) Habitat loss and fragmentation
(ii) Over-exploitation(iii) Alien species invasions(iv) Co-extinctions
BIODIVERSITY CONSERVATION :
Why Should WeConserve Biodiversity?
They can be grouped into three categories:
Narrowly utilitarian, Broadly utilitarian, Ethical
? How do we conserve
Biodiversity When we conserve and protect the
whole ecosystem, its biodiversity at all levels is protected - we save the entire forest to save the tiger. This approach is called in situ (on site)conservation.
When there are situations where an animal or plant is endangered or threatened and needs urge measures to save it from extinction, exsitu (off site) conservation is the desirable approach.
BIODIVERSITY CONSERVATION e
Biodiversity hot spots Biodiversity is not uniformly distributed
across the geographical regions of the earth. Norma Myers developed the hot spots
concept in 1988 to designate priority areas for in-situ conservation. The hot spots are the richest and the most threatened reservoirs of plant and animal life on earth.
The key criteria for determining a hot spot are:
i) Number of endemic species i.e., the species that are found nowhere else
ii) Degree of threat, which is measured in terms of habitat loss
The terrestrial biodiversity hot spots Twenty-five terrestrial hot spots for
conservation of biodiversity have been identified worldwide. Among the twentyfive hot spots of the world, two (Western Ghats and Eastern Himalayas) are found in India.
Biodiversity and Patterns of diversity.The importance of species diversity to the ecosystem.There are four major causes biodiversity lossesThe broadly utilitarian says that biodiversity plays a major role in many ecosystem that nature provides.The ethical argument for conserving biodiversity relates to what we owe to millions of plants, animals and microbes species withwhom we share this planet.Biodiversity has no boundaries and its conservation is therefore a collective responsibility of all nations.
Species-Area relationships
− Alexander von Humboldt observed that biodiversity increases with increase in explored area. This relationship can be given by,
log S = log C + Z log AWhere,S = Species richnessA = AreaZ = Slope
of the line (regression co-efficient)C = Y-intercept Value of Z is found to lie in the range of 0.1 to 0.2 for comparatively smaller areas such as countries while for very large areas such as entire continents, the slope of the line is much steeper with Z value lying from 0.6 to 1.2.
Species-Area relationships