ByM.Nadeem Ashraf2013-ag-10M.sc(Hons) Soil Science 1st SemesterEnvironmental Biology of Plants , BOT-709Environmental Changes and Lossof Biodiversity
Biodiversity is the variety of all life forms: thedifferent plants, animals and micro-organisms, theirgenes and the ecosystems of which they are a part.Biodiversity
Humans are dependent on biodiversity for theirsustenance, health, well-being and enjoyment of life. Food- we rely on biodiversity to provide us with alarge and varied food source Health- Humanity derives many of it’s medicinesfrom biodiversity.Importance Of Biodiversity
Recreation- many recreation activities relyon or benefit from biodiversityInspiration- Biodiversity as a whole inspiresartists, musicians and writers.Escape- Biodiversity provides a sanctuaryfrom the hustle and bustle of everyday life.The Value of Biodiversity
Sum total of biotic and abiotic components that createsfavorable and unfavorable conditions for the growthand survival of living entities. Segments of Environment: Atmosphere Hydrosphere Lithosphere BiosphereEnvironment
1. Climate change2. Loss of biodiversity3. Over-exploitation of the natural resource base4. Disruption to biogeochemical cycles and other aspectsof Earth system functioning5. Potential increase in hydro-meteorological extremeevents6. Air, water and soil pollution, and effects on humanhealth.What are the majorenvironmental challenges?
“Human Stupidity is infinite”(Albert Einstein)
Climate change is a change in the "averageweather" that a given region experiences. Average weather includes all the features weassociate with the weather such as: Temperature Wind patterns Precipitation.What is climate Change?
In the atmosphere, gases such as: water vapour carbon dioxide ozone methane Nitrous Oxide Chlorofluorocarbons (CFCs) These act like the glass roof of a greenhouse by trapping heatand warming the planet. These gases are called greenhousegases. The natural levels of these gases are being supplemented byemissions resulting from human activities, such as theburning of fossil fuels, farming activities and land-usechanges.FACING CLIMATE CHANGE
Harlequin FrogsAbout two-thirds ofCentral and SouthAmericas 110harlequin frog speciesare believed to havevanished during the1980s and 1990s. Theprimary culprit is thepathogenic chytridfungusBatrachochytriumdendrobatidis, whichhas been favored byglobal warming.
At threat of extinction are : 1 out of 8 birds 1 out of 4 mammals 1 out of 4 conifers 1 out of 3 amphibians 6 out of 7 marine turtles 75% of genetic diversity of agricultural crops has been lost 75% of the world’s fisheries are fully or over exploited Up to 70% of the world’s known species risk extinction if theglobal temperatures rise by more than 3.5°C 1/3rd of reef-building corals around the world are threatenedwith extinction Over 350 million people suffer from severe water scarcity.The International Union for Conservation of Nature(IUCN) notes in a video that many species arethreatened with extinction.
Dry and sub-humid lands, including arid and semi-aridareas, grasslands, savannahs, and Mediterraneanlandscapes, are home to 2 billion people (35% of theglobal population). These lands have great biological value and are home tomany of the world’s food crops and livestock.
Dry lands are particularly vulnerable to climate changebecause:• Small changes in temperature and rainfall patterns can haveserious impacts on the biodiversity of dry and sub-humid lands.• Dry lands are already under stress from various activities,including conversion to agriculture, the introduction of invasive species,alterations to fire regimes, and pollution. Many people are highly dependent on dry lands biodiversity. For example, about 70% of Africans dependdirectly on dry and sub humid lands for their daily livelihoods.Vulnerability to climate change
Even small changes in temperature and precipitationcan have significant effects on forest growth. It has been shown that an increase of 1°C in thetemperature can modify the functioning andcomposition of forests. Many forest-dwelling large animals, half of the largeprimates, and nearly 9% of all known tree species arealready at some risk of extinction. Woody tree species are less able to shift pole wardwith changing climatic conditions.Forest Ecosystems Forests are particularlyvulnerable to climate change because:
These are the 3 main concepts: More CO2 in the atmosphere means more CO2 in theocean; Atmospheric CO2 is dissolved in the ocean, whichbecomes more acidic; and The resulting changes in the chemistry of the oceansdisrupts the ability of plants and animals in the seato make shells and skeletons of calcium carbonate,while dissolving shells already formed.Increasing oceanacidificationNational Oceanic and Atmospheric Administration (NOAA)
Scientist agree that the current warming trend cant bestopped or reversed, but that it can be slowed down toallow biological system and human society more timeto adapt.Is it too late to stop climatechange?
Climate Change and Loss ofBiodiversity in Pakistan
Fourteen cyclones are recorded from 1970 to 2001 onSindh coast. Forests have declined from 260,000 hectares in 1970to just 86,000 hectares in Sindh(95%) and Balochistan(5%) coast. Mangroves absorb 70-90% of wave energy andeffectively stop sea encroachment in deltaic region.The fragile ecosystem of coastal belt isunder severe threat due to climate change.
.The fact that Pakistan is not a polluter yet it is on tophit list of 12 countries to be among the hard hitcountries due to climate change.Although Pakistan contributes least to globalwarming one 35th of the world’s average of CO2emissions.The level of air pollution in Pakistan’s large cities isestimated to be 20 % higher than internationalstandards.
Keti Bandar in the region of the coastal belt of Pakistanthat lost privileges of being at some point in time. Snow Leopards are disappearing The "Urial" with its rounded hornsPakistan’s economic system hassuffered greatly due to climaticchange
The Green Turtles are facingextinction all over the worlddue to low growth rate andenvironmental constraints.The Marine Turtle Project inPakistan is the last hope forthe survival of Green Turtlesin our region (Karachi)If the project was not there,our next generation wouldhave never known how theGreen Turtle looked like.
The "Gharial" orMugger Crocodilein Pakistan found inlakes and marshesaround Karachiendangered now.
The Houbara Bustardhas been over huntedas a game bird inPakistan. It is anendangered species.
An endangeredspecies ofHimalayans BrownBear, found only inthe northern areas ofPakistan, facingextinction .
In an effort to draw attention tothe mounting threats andopportunities, the CBDis calling on the nations of theworld to celebrate theInternational Day forBiological Diversity on 22 May2007 under the theme “climatechange and biodiversity”.