LECTURE 1: DEFINITIONS OF BIODIVERSITY, GENETIC, SPECIES AND ECOSYSTEM DIVERSITY

LECTURE 1: DEFINITIONS OF BIODIVERSITY, GENETIC, SPECIES AND ECOSYSTEM DIVERSITY

INTRODUCTION

1.Biodiversity is the short form of biological diversity. The term is used to describe the number, variety and variability of living organisms.

2. The convention on biological diversity defines biodiversity as “ the variability among living organisms from all sources including inter alie, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part ; this includes diversity within species, between species and of ecosystems.”[Art.2]
3. Why should we care about biodiversity?

In the recent years, the loss of entire species and natural areas, caused almost entirely by human activity, has been occurring at unprecedented rates.

4. The extinction of each additional species brings irreversible loss of unique genetic codes which are often linked to development of medicines, foods and jobs.
5. A widespread practice is to define biodiversity in terms of genes, species and ecosystems corresponding to three fundamental and hierarchically related levels of biological organization.

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GENETIC DIVERSITY

1. Genetic diversity refers to the variety of genes [biochemical units of hereditary information]; it is, therefore, a measure of variability both within and between species.
2. It brings out the differences in the genetic make-up among individual organisms.
3. Genetic diversity is what allows organisms to adapt to environmental change – an important consideration as the world enters an unprecedented period of climate change.
4. Genetic diversity represents the heritable variations within and between populations of organisms.
5. Ultimately, this resides in the sequence of the four base pairs which as components of nucleic acids, constitute the genetic code.

SPECIES DIVERSITY

1. Species diversity is considered as a measure of the total number of species in a given area.
2. The world’s species diversity is usually estimated at between 5 and 300 million species, though only about 1.4million of these have actually been named by scientist.
3. Species diversity is the most common measures of biodiversity. The number of species in a region is its species richness.
4. A more precise measurement of the species in a region is taxonomic diversity which considers the relation of species to each other.eg island diversity

A                                                      B

1. 3 species of birds 3 species: 2species of birds

1 species of lizards

1. Less taxonomic diversity greater taxonomic diversity

ECOSYSTEM DIVERSITY

1. Ecosystem diversity refers to the variety of habitants egforests , wetlands, savannas, coral reefs etc within which species occur.
2. Ecosystems by definition are composed of complex, interdependent groups of species [ plus non-biological components.] and contribute to maintenance of natural cycles of water carbon, oxygen, nitrogen, potassium and other elements as well as flow of energy upon which all life depends.
3. Ecosystem diversity is more difficult to measure than species or genetic diversity because the boundaries of communities [association of species] and ecosystem are blurred.
4. The relationship between the genetic, species and ecosystem diversity are complex and its important to remember that these are essential different groups of looking at the same thing.

LECTURE 2: MEGABIODIVERSITYCONSERVATION AREAS OF EAST AFRICAN

INTRODUCTION

1. Mega biodiversity is a term first proposed in 1988 by Smithsonian Institute of USA to describe nations that harbor the majority of Earths species.
2. It is an approach that looks at biodiversity priorities by political units, that is, sovereign nations rather than by ecosystem.
3. A mega biodiverse country is one that is rich in biodiversity.
4. Mega biodiversity concept recognizes a very small number of countries [17 out of a global 200] that are home to a large share of the world’s biodiversity[over 70%]
5. These countries include DRC, India, Indonesia, Australia, Brazil and USA among others.
6. Kenya, Uganda and Tanzania form East African mega biodiversity realm with high levels of genderism.

EAST AFRICAN BIODIVERSITY

1. East Africa is considered a significant Centre of global biodiversity in terms of the number of plants and animals and the variety of ecosystems it contains.
2. The natural features [lakes, mountains, savannas, coral reefs and the biodiversity they contain.
3. Kenya’s species diversity is estimated at about 35,000 known species of plants, animals and microorganisms.
4. The number includes 2500 animal’sspecies [mostly insects] and 3000 microbial species.
5. In Uganda 18400 species of plants, animals and microorganisms have been reported.
6. Of the relatively known species of birds and mammals, Uganda has 11.1% and 7.3% of the total world species respectively.

CONSERVATION AREAS

1. The concept of protected areas manage the worlds natural resources[biodiversity] was first put into practice in the USA in 1872, when the world’s first national park, Yellowstone National Park was established.
2. Since that time, many conservation areas have been established throughout the world and by 1986, over 2600 protected areas had been established, covering nearly 4 million km square in 124 countries. The number is still growing.
3. In Kenya the idea of national park was not conceived until 1946 when Nairobi National Park was established as the first national park in East Africa.
4. Today Kenya’s network of protected areas cover 8% of the total land area comprising 26 national parks and 30 national reserves.
5. Tanzania has several protected areas, world heritage sites and biosphere reserves which constitute 35.6% of the territory.
6. Forests in Kenya cover 1.4% million hectares.

LECTURE 3: USES AND VALUES OF BIODIVERSITY

INTRODUCTION

1. Biodiversity provides the basis of life on Earth.
2. The fundamental social, ethical, cultural and economic values of biodiversity have been recognized in religion, art and literature from the earliest days of recorded history.
3. Biodiversity not only provides direct benefits like food, medicine and energy but it also affords us “a life support system”.
4. Biodiversity is required for:
5. Recycling of essential elements such as carbon , oxygen and nitrogen,
6. Mitigating pollution,
7. Protecting watersheds
8. Combating soil erosion and,
9. Acting as a buffer against variations in weather and climate.
10. The ethical foundation of biodiversity is summed up by the statement “Everyform of life is unique, warranting respect regardless of its worth to man.”

VALUES OF BIODIVERSITY

1. Values of biodiversity can be classified as:
2. Direct values [consumptive use and productive use]
3. Indirect values [non-consumptive use option and existence]

DIRECT VALUES

1. Consumptive use values; non-market value of firewood , game meat, wild forests etc
2. This is the value placed on nature is products that are consumed directly without going through a market eg harvested species in form of food for rural poor vegetation game meet. Another example is firewood.
3. In Nigeria game constitutes about 20% of the mean annual consumption of animal protein by people in rural areas[ including 100,000 tons of giant rats known as “grasscutters”
4. Productive use values; commercial value of time, fish etc
5. This value is assigned to production that are commercially harvested for exchange in formal markets.
6. It is often the only value of biodiversity that is reflected in national income account. For example in 1994, more than 10 billion pounds fish valued at about 4 billion were caught and sold in United States alone.

INDIRECT VALUES

1. Non-consumptive use value: Environmental services, tourism, scientific research etc
2. Biodiversity provides environmental services without being consumed, traded in the market place or reflected in national income accounts.

These services include:

1. Photosynthetic fixation of solar energy;
2. Ecosystem functions eg pollination;

• Climate regulation;

1. Erosion control;
2. Stabilization of hydrological functions;
3. Storage and cycling of nutrients;

• Absorption and breakdown of pollutants; and
• Recreation , aesthetics and education

2. Option value: maintaining options for the future.
3. The future is uncertain and extinction is forever. Society should prepare for unpredictable events both biological and socio-economic
4. The best preparation in the context of biodiversity i.e, maintaining as many gene pools as possible, particularly those of wild species that are economically significant.
5. Existence value: ethical feelings
6. Many people attack value to existence of a species or habitant they have no intention of visiting or using. They hope their descendants [future generation] may derive some benefit from existence of these species.
7. The ethical factor is important in determining “existence” value which reflects sympathy, responsibility and concern that some people …….. toward species and ecosystems eg. Donations that WWT receives amount to $100million per year by people who do not expect to visit or use the resource they are helping conserve.

LECTURE 4: BIODIVERSITY DATA MANAGEMENT

INTRODUCTION

1. The convention on Biological Diversity [CBD] specifies on wide range of environmental activities requiring the use of biodiversity data.
2. These activities include[but are not restricted to]:
3. Biological survey and inventions
4. Biodiversity assessment and monitoring
5. Education and training
6. Public awareness and participation
7. Rehabilitation and restoration
8. In-situ and ex-situ conservation
9. Environmental impact assessment and
10. Socio-economic surveys and studies

BIODIVERSITY INFORMATION

1. Data and information are terms that are too often used interchangeably and its important to clarify the difference.
2. Data generally refers to the observations and or measurements describing a particular process.
3. Information however refers to data that have been organized, integrated and to some extend analyzed.
4. Knowledge can be derived from information through further analysis interpretation and understanding.
5. The ideal and product of this continuum is wisdom which is achieved through intelligent use of knowledge.
6. As one moves up the continuum from data collected toward wisdom the primer stakeholders involved in each activity change from these with a local focus to decision makers.

Figure 4.1. The nature of information

Decision support system

Increasing

Stakeholder

Modeling and analysis

Data collection

MOBILISING DATA

1. The concern to manage and exchange data on biodiversity comprise;
2. Data flexibility; to ensure that the data remains flexible [ie. It can be used for multiple purposes] they should be collected and stored in their primary form , not classified , aggregate d or interpreted, eg rainfall vs biodiversity
3. Data standard; data should be collected , managed, and exchanged following accepted standards [ conventions] to facilitate comparison f results in space and time.
4. Data quality; the quality of the data set they are a measure of its fitness for use for a specific purpose. An important aspect ie data quality assurance which enable stakeholders to use data reliably.
5. Data access; data access agreement are helpful in situations where stakeholders are concerned about potential exploitation and misuse. As confidence grows the need for formal agreements diminishes.
6. Appropriate knowledge; data should be managed within an environment conducive to data storage, processing and retrieval. Information and communication technology is ideally suited to this task and should be applied as appropriate and sustainable. This can lead to considerable cost savings and efficiencies in an organization.

LECTURE 5: THREATENED, ENDANGERED AND VULNERABLE SPECIES

INTRODUCTION

1. A threatened species is one thought to be at significant risk of extinction in the foreseeable future because of the factors affecting its populations, or by virtue of inherent vanity.
2. Public awareness of depletion and possible extinction of species led to the development of the Red Data Book by Sir Peter Scott in the 1960s.
3. This involved the categorization of the species at risk according to the severity of the threats facing them and estimated immense of their extinction.
4. This Red Data Book has been replaced by the IUcN Red list of threatened species which is compiled every year two years since 1986.

IUON THREAT CATEGORIES

The main IUON categories as used in the Red lists are:

1. Extinct (Ex): A species [or taxon] is extinct when there is no reasonable doubt that the last individual has died.
2. Endangered [En]: This is taxon in danger of extinction and whose survival is unlikely if the causal factors continue to operate.
3. Vulnerable [V]: A taxon believed to move into the endangered category in the near future of the causal factors continue operating [e.g. over-exploitation].
4. Rare [R]: Taxa with small world populations that are not at present endangered or vulnerable but at risk. These taxa are usually localized within restricted geographical areas or habitants or are thinly scattered over an extensive range.
5. Indeterminate [I]: Taxa known to be endangered vulnerable are rare but where there is not enough information to say which of the above categories is appropriate.
6. Insufficiently known [K]: Taxa that are suspected but not definitely known to belong to any of the above categories due to lack of information.

NOTES

1. The general term threatened is used to refer to a species considered to belong to any of the above categories.
2. These definitions apply to both plants and animals.

THREATS [a topic to be revised many times]

1. Most of the causal factors currently threatening species are anthropogenic in nature ie. Induced or influenced by man.
2. These factors include:
3. Habitant less or modification: often associated with habitant fragmentation.
4. Overexploitation: for commercial or subsistence reasons including meet, fur, hides collection of live animals for pet track and plants for the horticultural trade.
5. Exotic species: introduced accidentally or deliberately, which may compete with prey on or hybridize with native species.
6. Pests’ eradication: elimination of species considered as pests.
7. Incidental take: particularly of the drowning of aquatic reptiles and mammals caught in fishing nets.
8. Diseases: both exotic and endemic, exacerbated by the large numbers of domestic livestock or introduced plant species.
9. In the majority in this case individual species are faced by several of these threats operating simultaneously.
10. The major category of threats which affects 76% of species in Australia and Americas are habitant loss and modification (cultivation, settlement, pastoralism, logging, plantations etc.)
11. Overexploitation affects half the species, the most significant cause being hunting for meat.
12. Introduced predators and competitors affects 78% of the threatened species.

LECTURE 6: CAUSES OF SPECIES EXTINCTIONS

INTRODUCTION

1. A species become extinct when the last existing member dies.
2. Extinction becomes a certainity when there are no surviving individuals that can reproduce and create a new generation.
3. Determining the moment is difficult because a species range may be very large. This difficulty leads to a phenomenon known as Lazarus taxe where a species presumed extinct abruptly “re-appears” after a period of apparent absence.

BACKGROUND

1. Causes of extinction prehistorically have been dominated by natural earth processes such as geological transformation of the Earth’s crust and major climatic changes.
2. 99% of all species that ever lived on the planet are estimated to be extinct.
3. The primarily cause of human induced extinction is simply human overpopulation of planet Earth.

SPECIFIC CAUSES OF SPECIES EXTINCTIONS

1. The most important causes of human-induced species extinctions are:
2. Habitant destruction
3. Overexploitation
4. Pollution
5. Climate change
6. Exotic species
7. Disease and parasitism

1. HABITANT DESTRUCTION
2. This is the greatest contributor to extinction of many species
3. The destruction is ongoing in both terrestrial and aquatic ecosystems
4. In terrestrial ecosystems, destruction is due to agricultural expansion and urban converse.
5. In aquatic ecosystems, water pollution and trawling are significant causes.

OVEREXPLOITATION

1. Overexploitation presents itself in many forms such as overharvesting and overgrazing.
2. For example, tigers have been an integral part of china’s traditional medicine for over 1000 years, they have been hunted to the brink of extinction due to lucrative trade in tiger body parts eg black rhino

POLLUTION

1. Pollution is often a contributing factor along with habitant destruction
2. Air pollution and water pollution may cause reduction of species numbers within a given food web with serious ecosystem ramifications.

CLIMATE CHANGE

1. A review across 14 biodiversity research entries in 2013 predicted that, because of climate change 15-37% of land species would be committed to extinction by 2050.
2. The biodiversity rich African cape floristic region and Caribbean could seem doubling of present co2 levels and rising temperatures that will eliminate 56,000 plants and 3700 animal species (2050)

EXOTIC SPIECES

1. Introduced animal species could be predators of native species. Eg rats, kiwi species of New Zealand
2. Introduced exotic plants species could outgrow native species e.g prosodies juiliflora (mathenge)

DISEASE AND PARASITISM

1. The phenomena of disease and parasitism often weaken organisms and interfere with metabolic function.
2. Infections of bacteria and viruses may be a contributing  cause to species extinction.

BIODIVERSITY CONVENSION (habitat protection)

CNPA – commission on national park and protected areas

IUCN- inter union for conservation of nature

1984 proposed 10 categories of protected areas classified according to objective of management, and international system of protected areas

1.strict nature reserves/scientific reserve of protected areas ,,,,for environmental monitery and education

To protect outstanding natural and maintain natural process –Gombe stream in Tz

2.National parks

To protect outstanding nnatural and scientific area of national and international significant for scientific educational and recreational value e.g Nairobi national park

3.national monument/landmarks

Protect and preserve nationaly significant natural features coz opf their special and unique xteristics….GEDI national monument

4.manage nature reserve/world sanctuaries

To ensure maintenance of natural conditions necessary to protect nationally significant sppss /grps of spp biotic and communities ohr physical features of the environment where they may require specific human manipulation for their preparation…BOGORIA

5.protected land scape/sea scapes

To maintain nationally significant landscape that areof harmonious interactions of man and tyheland while providing  recreation..eg np exghesed

6.resource reserve

Protection of nature for future use and prevent e.g south Turkana national reserve

7.anthroecological areas /natural biotic areas allow the way  of living in harmony in the environment by modern technology…Kalahari game reserve in Botswana.

8 multiple use managed /managed resources area-to provide sustainable protection of h20 timber wildlife pasture tourism with conservation of nature ,primariliy oriented to suppooting economy e,g…Ngoro ngoro c,a

9.BIoshere reserve..conservation of the present and future use of the diversity and animal within natural environment…Mt kulal biosphere reservein kenya.

MAB UNESCO

10.world heritage sites

Protected natural resources for which areas protected  is considered to be of outstanding universal effect

11.ramser site

Convention of wetland to protect biodiversity of international importance ..lusingi kj 1992..Africa