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Notes towards Biodiversity Chapter 3
Introductory/Title slide (1)
Hello. This is Gwen Raitt. I will be presenting this chapter on the importance of
biodiversity.
Some things to consider.
The question asked on the title slide assumes that biodiversity is important, is it?
Biodiversity has been subject to huge losses (mass extinctions) before (Groombridge
1992). Why should we worry about it? Is our anthropocentric view of biodiversity the
only valid view? “What sort of world do we want to live in?” (p. 87 Gaston & Spicer
1998). “What sort of world are we prepared to pay to live in?” (p. 87 Gaston & Spicer
1998). If biodiversity is important, how do we use it sustainably? This chapter looks at
valuing and using biodiversity.
Ways of assigning value to biodiversity (Groombridge 1992, Gaston & Spicer 1998,
Lévêque & Mounolou 2001)
This does not only consider monetary value since monetary value is not easily assigned to
all categories of value (Groombridge 1992, Gaston & Spicer 1998, Lévêque & Mounolou
2001).
Non-use values of biodiversity are values that do not involve using or depleting the
resource as opposed to use values which generally involve the depletion of the resource
(Groombridge 1992, Gaston & Spicer 1998, Lévêque & Mounolou 2001). Biodiversity
may be valued for the use that is made of it either indirectly or directly (Lévêque &
Mounolou 2001). Indirect use values derive from ecosystem functions that are essential
to human welfare and are often termed ‘ecosystem services’ (Groombridge 1992, Gaston
& Spicer 1998, Lévêque & Mounolou 2001, Wikipedia Contributors 2006a, b). Direct
use values consider the direct use of biodiversity and transactions with biodiversity
(Groombridge 1992).
Note that many direct use values (such as agriculture, the production of medicines,
industry and live trade) require space which also affects biodiversity. In this chapter,
direct uses of biodiversity will be described and then linked to the indirect uses on which
they depend.
Intrinsic Value refers to the inherent value of any living organism without reference to
humanity (Kunin & Lawton 1996, Gaston & Spicer 1998, Wikipedia Contributors
2006a).
Additional Notes
Extract from Wikipedia (2006A) ~ http://en.wikipedia.org/wiki/. “Deep ecology is a
recent philosophy or ecosophy based on a shift away from the anthropocentric bias of
established environmental and green movements. The philosophy is marked by a new
interpretation of ‘self’ which de-emphasises the rationalistic duality between the human
organism and its environment, thus allowing emphasis to be placed on the intrinsic value
of other species, systems and processes in nature. This position leads to an ecocentric
system of environmental ethics. Deep ecology describes itself as ‘deep’ because it asks
complex and spiritual questions about the role of human life in the ecosphere.
Proponents of deep ecology believe that the world does not exist as a resource to be
freely exploited by humans. The ethics of deep ecology holds that a whole system is
superior to any of its parts. They offer an eight-tier platform to elucidate their claims:
The well-being and flourishing of human and nonhuman life on Earth have value in
themselves (synonyms: intrinsic value, inherent value). These values are independent of
the usefulness of the nonhuman world for human purposes.
Richness and diversity of life forms contribute to the realisation of these values and are
also values in themselves.
Humans have no right to reduce this richness and diversity except to satisfy vital human
needs.
The flourishing of human life and cultures is compatible with a substantial decrease of
the human population. The flourishing of nonhuman life requires such a decrease.
Present human interference with the nonhuman world is excessive, and the situation is
rapidly worsening.
Policies must therefore be changed. These policies affect basic economic, technological,
and ideological structures. The resulting state of affairs will be deeply different from the
present.
The ideological change is mainly that of appreciating life quality (dwelling in situations
of inherent value) rather than adhering to an increasingly higher standard of living. There
will be a profound awareness of the difference between big and great.
Those who subscribe to the foregoing points have an obligation directly or indirectly to
try to implement the necessary changes.”
Non-use values
Non-use values consider the potential benefits not yet realised and the benefits derived
from human awareness/perceptions of the world.
There are two forms of value that consider potential. Option value places value on the
potential benefits from future use of a resource (Groombridge 1992, Gaston & Spicer
1998, Lévêque & Mounolou 2001). Bequest value considers the potential benefits to
future generations from the use of a resource (Gaston & Spicer 1998, Lévêque &
Mounolou 2001).
There are two types of value related to human awareness and human perceptions.
Existence value refers to the value people attach to knowing that the resource exists even
though they have no expectation of seeing it (Groombridge 1992, Kunin & Lawton 1996,
Gaston & Spicer 1998, Lévêque & Mounolou 2001). Aesthetic value considers the
pleasure we take in the appearance of organisms and natural ecosystems (Kunin &
Lawton 1996, Miller 2002).
Indirect use values
Ecosystem services are strongly interlinked and consequently difficult to separate as can
be seen from the diagram. As a result, the diagram shown is probably incomplete.
The use of these ecosystem services is usually not sufficiently considered, which is why
we have problems with pollution. References giving indirect use values include
Groombridge (1992), Kunin & Lawton (1996), Patrick (1997), Gaston & Spicer (1998),
Lévêque & Mounolou (2001), Wikipedia Contributors (2006a, b, c).
Indicator of environmental resources
Direct use – indicator of environmental resources
Organisms may serve as indicators of desired resources. To illustrate, certain plant
species serve as reliable indicators of desired environmental conditions e.g. kapokbos
(wild rosemary - Eriocephalus africanus) indicated fertile soil suitable for agriculture in
the Swartland (pers. comm. Mr. M. Gregor 2003). The picture shows wild rosemary,
Eriocephalus africanus. A further illustration is that some plant species have affinities to
certain metals. Berkheya coddii may be endemic to nickeliferous serpentine soils
(Morrey et al. 1989).
Indicator of environmental resources – dependence and effect
Dependence, as used here, refers to the reliance on indirect use services to sustain the
direct use. The use of plants as indicators of environmental resources is dependent on
autecological knowledge of the plant species. Such knowledge depends on
observations/studies of the species in its natural habitat which means that it is dependent
on all the ecosystem services to maintain it. Unfortunately the use of the resources
indicated by the plant species tends to be detrimental to the continued existence of all the
native species in that area.
Direct use - food production
Most of what we eat is produced by living organisms – either through agriculture or
through harvesting from the wild (Groombridge 1992, Kunin & Lawton 1996).
Subsistence farmers particularly benefit from biodiversity by harvesting the natural veld
(Kunin & Lawton 1996, Lévêque & Mounolou 2001). Natural products also contribute
to other areas of food production. Food additives such as spices may also be natural
products (Nations 1988, Pietra 2002).
Aids to food production such as pesticides, insecticides, fungicides and fertilisers may be
derived from biological sources (Plotkin 1988, Groombridge 1992, Kunin & Lawton
1996, Pietra 2002).
Genetic improvement of domesticated species is achieved by crossing them with wild
species or by gene transfer (Kunin & Lawton 1996, Lovejoy 1997, Lévêque & Mounolou
2001). The process of cross breeding takes time, e.g. the value of a wild tomato species
was only visible about 17 years after its discovery (Iltis 1988). Biotechnology will
probably decrease the time needed to derive a benefit from wild species.
The related non-use value (a form of option value) is that new species for agricultural use
may be found in nature. More variety would help to reduce our dependence on a limited
number of species (Plotkin 1988).
Food production – effects and dependence
As the picture shows, food production requires space, displacing the natural biodiversity.
The survival of species harvested from the wild is threatened by overexploitation (Kunin
& Lawton 1996, Lévêque & Mounolou 2001). Wild harvesting is dependent on all the
different ecosystem services to sustain the production of the harvested species.
Agriculture is dependent on ecosystem services to provide a suitable environment for the
production organisms (plant and animal). The ecosystem services include biological
control of soil organisms (Patrick 1997), nutrient cycling, pollination, soil formation and
maintenance, soil fertility and water purification for plant production and all of the above
with the addition of food sources for animal production (Patrick 1997, Wikipedia
Contributors 2006a).
Biological control
Direct use – biological control
The direct use of a natural enemy to control a pest organism is known as biological
control (Kunin & Lawton 1996). The picture shows the fungus Uromycladium
tepperianum on Port Jackson (Acacia saligna). This is an example of biological control
in South Africa. See the Invasion Biology Course (chapter 8) for more detail.
Biological control – dependence
Biological control makes direct use of the natural biological control exerted by
ecosystems in an unnatural context. The biological control agent is dependent on all
ecosystem services that support its host, e.g. nutrient cycling and habitat. The
maintenance of a habitat involves all the other ecosystem services.
Direct use – medicine
Many medicines were identified from various organisms e.g. aspirin, now synthetically
produced, was found in the willow tree (Salix alba) (Lovejoy 1997, Pietra 2002).
Commercial production of organisms for the extraction of medicines and direct
commercial production of biodiversity derived medicines are important sources of
medications (Farnsworth 1988, Pietra 2002, Wikipedia 2006a).
Many people cannot afford modern medications so they rely on traditional medicines.
These medicines are extracts of organisms taken from the wild (Plotkin 1988, Kunin &
Lawton 1996, Lévêque & Mounolou 2001, Pietra 2002).
Animals are used for commercial product testing e.g. armadillos (Dasypus novemcinctus)
have been used to study leprosy (Nations 1988, Kunin & Lawton 1996).
A non-use value related to the direct medical use of biodiversity is that biodiversity offers
abundant potential for new medicines (Farnsworth 1988, Kunin & Lawton 1996, Lévêque
& Mounolou 2001).
Medicine – dependence
Agriculturally propagated medicinal species require the ecosystem services that are
required by agriculture. Chemical production of medicines is dependent on the water and
air purification and waste treatment services of ecosystems. Wild harvesting for
traditional or other use is dependent on all the different ecosystem services to sustain the
production of the harvested species. The use of animal testing of medicines requires a
supply of food for the animals which means that the ecosystem services required to
produce the food are also used.
Direct use – industry
Raw materials for industrial use include timber, rattans, fibers, oils, fats, resins, waxes,
dyes, fuels, cellulose, latex, cork, lubricants, poisons, scales, bones, hides and rubber
(Nations 1988, Plotkin 1988, Groombridge 1992, Kunin & Lawton 1996, Patrick 1997,
Lévêque & Mounolou 2001, Wikipedia Contributors 2006a).
Products include cosmetics, scents, clothing, paper, etc. (Plotkin 1988, Pietra 2002,
Wikipedia Contributors 2006a). For more information on direct industrial use and
depletion of biodiversity see Plotkin (1988), Groombridge (1992), Pietra (2002) and
Wikipedia Contributors (2006a).
Some species (e.g. microbial species and plant species) may serve as tools for the
extraction of minerals. This is known as biomining (ucbiotech.org undated). If the
species used are plants, the term used is phytomining. A crop of metalhyperaccumulators is grown then the biomass is harvested and burnt to provide bio-ore.
Berkheya coddii (a South African species) is an efficient Ni (nickel) hyperaccumulator
(Anderson et al. 1999). Berkheya coddii leaves have significantly higher concentrations
of Ni (nickel) than either the soil or bedrock on which it grows (Mesjasz-Przybylowicz et
al. 2004).
A non-use value related to the direct industrial use of biodiversity is that biodiversity
offers a source of new materials for industrial use (Nations 1988, Plotkin 1988).
Industry – dependence
For farmed raw materials (e.g. timber) the same dependence occurs as in agriculture:
biological control of soil organisms, nutrient cycling, pollination, soil formation and
maintenance, soil fertility and water purification for plant production and all of the above
with the addition of food sources for animal production. Wild harvesting is dependent on
all the different ecosystem services to sustain the production of the harvested species. All
industry is dependent on natural systems for water and air purification and waste
treatment.
Bioremediation
Direct use – bioremediation
Bioremediation is the use of biological organisms or their products (e.g. enzymes) to
remove or detoxify contaminants from hazardous waste and contaminated soil or water
(Miller 2002, Cunningham et al. 2003). A species of bacteria found in the Potomac
River’s sediments can breakdown chlorofluorocarbons (CFCs) (Lovejoy 1997). Poplar
trees (Populus spp. and hybrids) are used to clean contaminated industrial sites (Miller
2002). The picture shows a hybrid poplar tree.
Bioremediation – dependence
Bioremediation depends directly on the ecological services of waste treatment and water
purification in an unnatural setting.
Indicator of ecological change
Direct use – indicator of ecological change
Changes in the levels of biodiversity or individual species ranges may be used to indicate
changes in the state of the ecosystem (Lovejoy 1997) e.g. lichen species (some are
pictured) serve as indicators of air quality (Monaci et al. 1997, Vokou et al. 1999). Such
indicator species are known as bioindicators (Wikipedia Contributors 2006d). In some
cases, it may be possible to isolate the causes of the disturbance and remove them.
Indicator of ecological change – dependence
Changes in biodiversity reflect changes in the ecosystem that have changed the
functioning of ecosystem services. This use of biodiversity relies directly on the
organisms to indicate the condition of the ecosystem of which they are a part.
Direct use – ecotourism and recreation
People pay to view biodiversity in the natural environment. This is termed ecotourism
(Lévêque & Mounolou 2001). Ecotourism is a growing industry that needs to be
controlled so that it does not harm the resources it is using (Gaston & Spicer 1998,
Lévêque & Mounolou 2001).
There are various forms of recreational use of biodiversity. It should be noted that some
need not take place in a natural setting. Gardening is recreational (for some people) but
not natural. Camping, hiking (Miller 2002) and sometimes mountain biking may be done
in natural environments. Sports such as fishing, hunting and falconry (Groombridge
1992, Kunin & Lawton 1996) involve natural or disturbed environments.
Additional Notes
Extract from Miller (2002) pp. 562, A11: “Ideally, ecotourism (1) should not cause
ecological damage, (2) should provide income for local people to motivate them to
preserve wildlife, and (3) should provide funds for the purchase and maintenance of
wildlife preserves and conservation programs. However, most nature tourism does not
meet these goals and excessive and unregulated ecotourism can destroy or degrade fragile
areas and promote premature species extinction.”
“Evaluating Ecotours Before embarking on an ecotour, seek answers in writing to the
following questions: What precautions are taken to reduce the tour’s impact on local
ecosystems? How much time is spent in the field, versus in the city or traveling in a
vehicle? What happens to the tour’s garbage? What percentage of the people involved in
planning, organizing, and guiding tours are local? Are the guides trained naturalists?
Will you stay in locally owned hotels or other facilities, or will you be staying in
accommodations owned by national or international companies? Does the tour operation
respect local customs and cultures? If so, how? What percentage of the tour’s gross
income goes into the salaries and businesses of local residents? What percentage of the
tour’s gross income does the tour company donate to local conservation and social
projects?”
Ecotourism and recreation – dependence
Ecotourism is dependent on all ecological services. Recreational activities such as
gardening rely on the same ecosystem services as agriculture, including nutrient cycling,
soil fertility and soil formation and maintenance. Camping, hiking and mountain biking
in natural areas rely on all ecological services to maintain the aesthetic appeal of the
environment. Sports such as fishing, hunting and falconry rely on prey species and the
ecological services that sustain them – food sources and habitats which require all the
ecological services to maintain them. The picture shows hiking trails on Table Mountain.
Working animals
Direct use – working animals
Various ‘wild’ animal species have been trained to aid man (Groombridge 1992), e.g.
Asian elephants (also known as Indian elephants, Elephas maximus) are trained as
draught animals (Groombridge 1992, Wikipedia Contributors 2006e) and the fishing
industry in China and Southeast Asia makes use of otters (Lutra spp.) and cormorants
(Phalacrocorax spp.) (Groombridge 1992).
Working animals – dependence
Farmed working animals require the same inputs as for agriculture i.e. biological control
of soil organisms, nutrient cycling, pollination, soil formation and maintenance, soil
fertility and water purification and food sources. Wild harvesting of animals is dependent
on all the ecosystem services to sustain the organisms for harvesting.
Cultural use
Direct use – cultural
Biodiversity serves as a source of inspiration for art, poetry and literature (which may be
a direct use value or a non-use value in the form of aesthetic appreciation) and influences
philosophy, language and religion in many societies (Groombridge 1992, Lévêque &
Mounolou 2001). Biodiversity may also supply the medium in which the art is expressed
– e.g. canvas for painting and wood for sculptures.
Cultural – dependence
In as much as any aspect of biodiversity may provide inspiration, cultural diversity is
reliant on all ecological services to maintain the source of inspiration. Materials for use
in art are the products of industry so the ecological services needed by industry apply –
air and water purification and waste treatment as well as supports for production.
Products harvested in the wild for cultural purposes rely on all ecosystems services to
maintain the product.
Knowledge
Direct use – knowledge
Each species provides unique information that is lost if the species becomes extinct.
Species, species interactions and intact ecosystems are important research areas (Kunin &
Lawton 1996). Biodiversity provides clues on evolution, past and present and
biodiversity presents insights into how life functions (Wikipedia Contributors 2006a).
Knowledge – dependence
All ecosystem services are needed to develop an understanding of biodiversity.
Live trade
Direct use – live trade
Ornamental plants including geophytes, orchids and succulents were originally taken
from the wild. Some species are still harvested from the wild. This poses a major threat
to the survival of certain species in the wild (Groombridge 1992, Kunin & Lawton 1996).
Plants are also traded for cultural and medicinal purposes.
As with plants, animals were originally taken from the wild as beasts of burden, food and
pets. Some species were domesticated. The existence of certain species in the wild is
threatened because of continued harvesting from the wild (Groombridge 1992, Kunin &
Lawton 1996). Animals are traded for laboratory use, recreation and ecotourism (Kunin
& Lawton 1996, Van der Waal & Dekker 2000). Not all live trade is legal, which makes
controlling it difficult (Brooks et al. 2006).
Live trade – dependence
Farmed organisms for live trade require the same inputs as for agriculture, i.e. biological
control of soil organisms, nutrient cycling, pollination, soil formation and maintenance,
soil fertility and water purification for plant production and all of the above with the
addition of food sources for animal production. Wild harvesting of both plants and
animals for live trade is dependent on all the ecosystem services to sustain the organisms
for harvesting.
Problems with monetary values and societal control
Market values do not reflect the impacts of use on society and biodiversity (Perrings
1995, Lévêque & Mounolou 2001), e.g. the market value of timber extracted from
tropical forests does not reflect the loss of ecological services or the loss of forest
products to the locals (Lévêque & Mounolou 2001).
Short term vs. long term benefits. The long term benefits of ecosystem services are
difficult to quantify monetarily and short term monetary gain is appealing especially as
money may increase faster than the resource reproduces (Dobson 1996, Kunin & Lawton
1996). The rarity of a species increases the monetary value of the product though the
costs of obtaining it also increase (Dobson 1996). The development of new biodiversity
products takes time (Iltis 1988).
The ownership of resources affects their use. Cumulatively, shared resources are likely
to be over utilised because each individual is considering his/her own interests not the
collective interest (Miller 2002). Someone else will use this if I do not (Dobson 1996,
Miller 2002). The resource is renewable, “the little bit that I use or pollute” will not be
enough to matter (p. 12 Miller 2002). To prevent this, regulations need to be established
and enforced (Miller 2002).
Who benefits? Informal vs. formal markets – political hierarchy (Kunin & Lawton 1996,
Lévêque & Mounolou 2001), e.g. a piece of tropical forest will supply the locals with
various products which they will use and trade locally. The timber from the same piece
of forest will be sold internationally providing foreign exchange, the benefits of which
are reflected at a national level, usually without any benefits to the locals. Though the
timber income is once off and considerably less than the cumulative local income, the
probability is that the national benefit will outweigh the local benefit should the
government be approached concerning the timber (Kunin & Lawton 1996, Lévêque &
Mounolou 2001).
Last slide
I hope that you found chapter 3 informative and that you will enjoy chapter 4.
The picture shows a view over the Hluhluwe-Umfolozi Game Reserve.