Conservation by pengxuezhi

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									                                                     Conservation


Conservation
=   defined as the human management of Earth’s physical and biological resources in such a way as to
    give all forms of life, including humans, the best chances in a shared future
    (i.e. both taking action and expressing concern to protect the environment and keep it healthy)


-   so, we need to understand what is happening in our environment to be able to know how to look after
    it
    (acheived from study of ecology and the other environment science)


-   often has a moral and political dimension and hence requires an integration of scientific and social
    objectives


-   conservation is needed because:
    -- pressures placed upon the natural environment is increasing
    -- widespread loss of natural habitats
    -- growing numbers of extinct and endangered species
    -- maintain biodiversity is significant in maintening the stability of the ecosystem, conversation of
             valuable genetic characters in the gene pool and possibility of evolution under environmental stress

         Biodiversity refers to species diversity, genetic diversity and ecosystem diversity.


         -     all life forms are part of nature and each of them has a specific role in it. There is a
               continued threat of loss of species which amy lead to its extinction. The loss of any one life
               form is irreversible.
         -     Oraganisms in an ecosystem are interdependent. Each of them is an important part of the
               food chain and plays a specific role in the ecosystem.
         -     Ecosystem diversity is ecologically important. For example, forests help prevent soil
               erosion and blance of oxygen and carbon dioxide in the atmosphere.
         -     Genetic diversity is economically important. Plant breeders and farmers rely on genetic
               diversity to improve crop yields and improve resistance to pests and diseases. A loss of
               species would mean a loss of resources for human use (e.g. food, medicine etc.)
         -     Biodiversity is just as important a part of our heritage as art, language and achievement.
               Man has the role of stewardship of the natural world.


         Conservation of biodiversity is not just a modern term for conservation of organisms. In
         addition to conserving organisms, it encompasses conservation of the genetic diversity as well
         as their living environment.
I. Conservation Methods
A. Agriculture activities
  a. Crop rotation on Monocultured land
      =     a planned system of growing successive types of crops in a particular area of soil over a period
            of time
           avoid turning a land into bad land due to depletion of a particular types of minerals


      -     a common plan of crop:
            1st crop: deep root system  take in minerals from deeper soil
            2nd crop: short root system  take in minerals from top soil
            3rd crop: leguminous plants  produce nitrates and make the soil more fertile


      -     advantage of crop rotation
            -- more than one crops in a year in a field
                increase yield and maximize the land use
            -- avoid depletion of a particular types of minerals
            -- increase fertility by legumes
            -- break life cycle of plant parasites


b. Careful handling of fertilizer
      -     prevent spreading of diseases via organic fertilizers
      -     enrich nearby water due to leaching of inorganic fertilizers


c. Avoid too much of pesticides and herbicides
      -     prevent accumulation of the chemicals along food chains
      -     prevent appearance of resistance stains


B. Prevention of over-grazing
  protect the land from soil erosion


C. Renewable resources
  a. farming of wild animals
  -       development of farms which produce sought-after goods
           reduce the stress on wild life
      e.g. mink farming, deer farming
           produce enough material to satisfy the market and so remove the necessity to kill these animals
            in the wild
b. Removal of species from threatened areas
- organisms in habitats threatened by humans, or by natural disasters such as floods, may be removed
  and resettled in more secure habitats
c. Artificial breeding of endangered species in zoos and botanical gardens
- artificial or natural breeding in protected environment
- followed by reintroduced into the wild when numbers have been sufficiently increased
- Mordern Biotechnology
  e.g. genes libarary, cloning of individuals from single cells…etc.


e. Conservation of genetic variety
- worldwide establishment of seed and sperm banks ensures survival of potential materials from which
  to develop new varieties of food crops and domestic livestock, even when facing any significant
  physical or biotic environment change


f. Sustainable Yield Management        (e.g. Fishery (2001-Al Bio II-C8) , Timber)
  (1). Avoidance of overcropping
        left rooms for renewal and compensation of the loss from cropping
  (2). protect the young and ‘seeds’ for reproduction
  (3). setting facilities to prevent or minimize the adverse effects caused by disaster on ecosystem
  (4). restoration of destructed of habitats, eg. afforestation after deforestation
                                      Focus (1): The management of Forestry
Forestry = the science of planting and caring for forest

Forestry in Hong Kong
1. Damage of the forests
   - during the 16th and 17th centuries the forests in H.K. were cleared by government to discourage armed
     robbery
   - in recent years the forests in H.K. are mainly damaged by hill fires caused by the careless picnickers

2. Use of forests in H.K.
   - the forests are mainly used to prevent soil erosion in the slopes around the reservoirs. They also help to hold
     water in the eater catchment area
   - the forests in the country parks provide scenic and recreational amenities to the citizens while the nature
     tails give educational opportunities to the students
   - the forests in reserve areas help to conserve the wildlife

Management of a forest
1. Remedy in forestry
   - deforestation should be followed by afforestation
      to achieve a balance between harvest and renewal so that:
          -- a continuous yield of timber is maintained
          -- habitats and shelters for oganisms is maintained
          -- soil erosion prevented

  - restrict the lumberman to cut only the old trees, but not the young trees
  - harvest timber by rotated cutting

2. Protection aginst hill fires
   - fire barriers:
     -- clear areas resembling roads,
     -- fire resistant plant species
      form gaps in forests that suppress the spread of hill fires

  - 24-hour stand-by fire-fighting team should station in certain sites during dry seasons, with tools
     to combat against hill fires efficiently at the shorest period of time

  - Barbecue stoves are built in certain sites where the hill fire hazard is lowest
     avoids picnickers set their fires for barbecues randomly which easily leads to hill fire

3. Education

4. Forest set up as country park, nature trails, reserve areas and Environmentally Sensitive Area (ESA)
    - provide senic and recreational amenities to citizens
     - provide educational opprtunities to students
     - help to conserve the wildlife

5. Policy and Laws
   - prevent pollution and illegal wood cutting
   - legal protection for endangered species
   - in H.K. the continuous supervision of country parks by the staff of the Conservation and Forestry Division
     of Agricultural and Fisheries Department

6. Planned land use
   the type of activities permitted on the land are carefully controlled by legislation
                          Focus (2): The management of Fishery


1. Prevent underfishing
  - under conditions of light fishing a fish population grows to the limits of food supply,
    the carrying capacity (K) in the absence of significant human predation


  - slow-growing older fish compete successfully for food
     fish catch show a predominance of poor quality old fish


  - reduction in population size by removing the excess lod fish would achieve a better
    growth rate through the remaining stock and improve the condition of the fish


2. Prevent overfishing
   ensure a continuous yield of fish stock the total amount of fishing must be restricted by
    the following means:
    - limit the total permitted annual catch of fish
    - limit the size of fishing fleet
    - limit the length of fishing season
    - limit the fishing area


   ensurer good-sized fish to be caught, the following restrictions are required:
    - forbid the landing of under-sized fish
    - forbid fishing in nusery area to enable the young fish growing to mature one
    - forbid small mesh and hook sizes so that they cannot be usd to catch small fish
g. Planned land use, Maintenance and management of habitats
  --   prevent serious local pollution due to high density of certain kinds of industry
  --   prevent or minimize any destruction of habitats of wild life
  --   prohibit the conversion of farmland to residential, commercial and industrial uses … etc.
  --   tree planting in urban and rural areas help to improve the living environment for man and other
       organisms. (97-AL BIO II- C8)
  --   included development of national parks and natural reserves to reserve wild life, for recreation,
       and eduction


       - Country Parks (http://parks.afcd.gov.hk/newparks/eng/country/index.htm)
         -- countryside is a natural resource that meets the recreational needs of people.
         -- under the 1976 Country Parks Ordinance, legislation was acomplished for about 16
            Country Parks have been established and they occupy about 40% of the hilly areas of Hong
            Kong
         -- if a Country Park is not properly managed, its natural vegetation may be ruined by fire left
            by careless picnickers and the great beauty of nature may be destroyed by littering due to
            the ignorance of the visitors


         -- Objectives of setting up the Country Parks:
            i.   Conserve the natural beauty.
                 park wardens and staff have to be on duty to prevent hill fires, avoids excessive use of
                 popular places and to remove rubbish regularly
            ii. Provide opportunities for the public to have recreation in nature.
                 barbecue stoves and picnic facilities are provided in the popular zones where danger of
                 hill fire is lowest
            iii. Preserve the wildlife to maintain the ecological balance
                 certain areas are restricted to enter unless apermit is granted so as to protect the
                 wildlife there
            iv. Educate the public the essential features in nature
                 nature trails are set up to meet this need
            v.   Provide opportunities to study the plants and animals so as to investigate the ecological
                 factors required for maintaining balance in nature, such knowledge forms the basis for
                 conservation action taken


       - Others:
         -- Sites of Special Scientific Interest (SSSI),
         -- marine parks (97-Al Bio II-C10), http://parks.afcd.gov.hk/newmarine/eng/index.htm
         -- artificial reefs (2000 Al-Bio II- C7)and
         -- Ramsar site (http://www.wwf.org.hk/chi/maipo/ramsar/index.html)
i. Human activities restriction
  (1) restriction of habitat destruction activities
        eg. mining, deforestation (99-Al Bio II-C10), reclamation (99-Al Bio II-C8)


  (2) restriction of hunting, trading and keeping of wild species
       - illegal to collect or kill certain species, eg. Koala in Australia


  *      in H.K. by law the following wild animals are protected from hunting:
         -- barking deer,
         -- crab-eating mongoose,
         -- five-banded civet,
         -- leopard cat,
         -- masked palm-civet,
         -- otter,
         -- pangolin,
         -- South China red fox,
         -- wild boar,
         ** Chinese White Dolphin,
         ** Romer’s Tree Frog,
         ** Black-faced Spoonbill              Endangered species being protected in Hong Kong
         ** Pitcher-plants …etc.


       - restrict the import of new species (exotic species)
             prevent disturbance to balance of local ecosystem


  (3) restriction of recreation activities
       - restrict disturbance and pollution causing acitvities
D. Demand on renewable and Non-renewable resources
  - Reduce consumption, reuse, recycle of wastes and replace (4R, e.g. paper, aluminium)
     - reduce exploitation and prevent depletion of resources, especially the non-renewable ones
       - reduce disturbance to ecosystems during exploitation
       - reduce production of pollutants


       - eg. -- cotton waste is used as the organic substrate for growing editble mushrooms
            -- destructive distillation (= a process by which a material is decomposed by heating to about
               1,650 oC in the absence of air) recycles the non-metal wates into sources of energy in form
               of oil, gas, steam and methane without discharging pollutants into atmosphere
            -- in H.K. metals from ship-breaking and old car are recycled as framework for reinforcd
               concrete
            -- means of energy conservation:
               - economize the use of electricity
                   helps to cut down demand on fuels used to generate electricity
               - improve the efficiency of engines to ensure the complete combustion of fuels so as to
                  save fuel as well as to reduce air pollution
               - develop economic techniques to get energy from sources other than petroleum
                  e.g. from nuclear reactors, water, sunlight, wind, tidal action, current and earth heat.


E. Pollution (2001-Al Bio II-C10)
  Proper waste treatment and disposing
   reduce production of pollutants, remove the pollutants by treatments, or reduce the adverse effects
    caused by pollutants in wastes onto the environment


  In HK:
  - sewage treatment (up to secondary treatment)
    http://www.dsd.gov.hk/sewerage/our_sewage_treatment_facilities/type_of_sewage_treatment_faciliti
       es/index_c.htm
  - treatment plants: distribution, types of treatment and facilities
    http://www.dsd.gov.hk/sewerage/our_sewage_treatment_facilities/index_c.htm
    http://www.dsd.gov.hk/sewerage/our_sewage_treatment_facilities/list_of_sewage_treatment_facilitie
       s/index_c.htm


    (Sewage treatment: see notes --- Human Activities and Ecosystem )


F. Policy and Legislation
    http://www.info.gov.hk/epd/tc_chi/laws_regulations/envir_legislation/laws_overview.html
    http://www.afcd.gov.hk/con_new/chinese/homepage.htm
G. Eudcation
    -    all of the above require people with good sense of conservation to cooperate and do with


    -    can be acheived by:
         --    mass media, e.g. news paper, television…etc.
         --    school learning
         --    outdoor or indoor activities e.g. trackling, picnic, planting …etc.


II.The dilemma between urbanization, industrialization and conservation.
    Any piece of goods or any type of service that is based in some way on production by ecosystems will
    have an upper limit to growth or be recycled.


    Whatever economic growth there has been in the past, for however long, has been a reflection of
    exploitation of space and resources and expanding populations with expanding (creating) needs .


    Cost-Benefit Ratio:
    -   cost for conservation and pollution control
          reduce profits (benefit)
    -   Impact of habitat distrubance and pollution
          reduced yield (productivities) and high cost for clean up and re-establishment.


    How can economic activities be directed so as to improve the quality of life for all human beings
    and the nature?
    In 1987 the Commission issued its report and called fro future economic growth:
    ‘   based on policies that sustain and expand the environmental resource base.      ’


    Among other things, the Commission recommended that ecological considerations be given equal
    status with other factors such as economics, agriculture, and trade in policy making worldwide.


    In the past, ecological and environmental factors were not taken into account as part of the cost of
    doing business, and in the future they must be. That means that there mist be a transition from
    environmental protection being an external factor to its being fully included in the cost accounting
    that leads to the determination of the prices of products that are bought and sold in our society.


    Among the important principles and concepts in economics that bear on the need for this transition is
    the so-called law of supply and demand and the concept of margin.


    Sustainable development as defined by the Brundtland Commission:
    is development that meets the needs of the present without compromising the ability
    of future generations to meet their own needs.
The World Wide fund for Nature (WWF), in collaboration with the World Conservation Union
(IUCN) and the United Nations Environment Programme (UNEP), further developed the notion of
balance in Caring for the earth, defining sustainable development as:
 "improving the quality of human life within the carrying capacity of supporting system".


Reference:
世界自然 (香港) 基金會 http://www.wwf.org.hk/chi/references/index.html

								
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