Report 7 Flashcards
‘Keystone Species’ was introduced by
Robert T. Paine in 1969
Two basic criteria of keystone species have been proposed by Mills et al.
i. The presence of keystone species is crucial in maintaining the organization and diversity of their ecological communities.
ii. These species are exceptional, relative to the rest of the community, in their importance.
examples of keystone species:
- sea otters (Enhydra lutris) and sea urchins (Strongylocentrotus spp.) feed over kelps
- Solenopsis geminate (Fire ants) exclusion increases the number of arthropods which are harmful to agriculture.
- Humming bird pollinators.
- Terborgh proposed the palm nuts, figs and nectars as keystone resources because of their extreme significance for fruit and nectar eating species of tropical forest like the primates, squirrels, rodents, and many birds.
examples of keystone species:
- Caster canadensis (North American beavers) make dams which can change hydrological and biogeochemical factors of the region to alter the productivity.
- Cornitermes cumulans (Brazilian termites) make bulky, rich and distinctively designed mounds which has wide range of obligate users.
- Sea urchins grazing prevents the transition from encrusting algae dominated community to a large, fleshy algae dominated one.
*Thomomys bottae (Pocket gophers) maintain mountain meadow communities.
Threats to Biodiversity
- Escalating Extinction Rate
- Irreversible Loss
- Climate Change as a Threat
to standardize terminology for threats to biodiversity, making it easier to compare and generalize data across ecosystems. It includes threats from alien species, genetic material, and interactions among native species
threat classification system
The IUCN classification distinguishes between ______________, such as geological events, climate changes, and severe weather, and direct threats to biodiversity.
abiotic threats
The World Conservation Union–Conservation Measures Partnership (IUCN-CMP) proposed a ________________ that contribute to biodiversity loss, defining stresses as degraded conditions resulting from direct threats.
classification of stresses
Biodiversity faces severe threats from a combination of anthropogenic and natural factors
multifactorial threats
A comprehensive classification of direct threats to biodiversity proposed by Salfasky et al.
- residential and commercial development
- agriculture and aquaculture
- energy production and mining
- transportation and service corridors
- biological resource use
- human intrusions and disturbance
- natural system modifications
- invasive and problematic species and genes
- pollution
- geological events
- climate change and severe weather
evaluated tens of thousands of species worldwide and categorized them as threatened with extinction. This included species classified as critically endangered, endangered, and vulnerable. Several taxa, including amphibians, corals, conifers, mammals, and birds, were reported to be at risk
2012 IUCN Red List
The stress classification for biodiversity proposed by Salafsky et al
Ecosystem / community stresses
Ecosystem conservation
Ecosystem degradation
Indirect ecosystem effects
Species stresses
Species mortality
Species disturbance
Indirect species effects
Threats to global biodiversity
Habitat loss through degradation and fragmentation
Population growth and Poverty
Over exploitation of natural resources
Invasive species
Climate change and Pollution
Disease
Weak enforcement of law
Background extinction
Stochastic events and Hunting for food
Habitat is lost through conversion to agriculture and housing
when there is no reaso nable doubt that the last individual has died
extinct
it is known only to survive in captivity, or as a neutralized population outside its historic habitat.
extinct in the wild
it is facing high risk of extinction in the wild in immediate future.
critically endangered
it is facing very high risk of extinction in the wild in near future
endangered
it is facing very high risk of endangered in the wild in near future.
vulnerable
it is likely to become endangered in near future.
near to threat
A taxon with lowest risk. These are the widespread and abundant taxa.
least concern
there is inadequate information to make any direct or indirect assessment of its risk of extinction.
data deficient
it has not yet been assessed against the above criteria.
not evaluated
Conservation strategies are broadly classified into two categories:
in-situ conservation (conserving species in their natural habitats)
ex-situ conservation (conserving species outside their natural habitats)
defined as “the conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings and, in the case of domesticated or cultivated species, in the surroundings where they have developed their distinctive properties”
In-situ Conservation
More than ________ of National Parks have been established throughout the world, out of which nearly one-third is confined to Asia.
3000
is distinctive in abundance and multiplicity of its flora and wild life and has about 166 authorised National Parks throughout the country.
india
India also accommodates about 515 animal sanctuaries which are called as
wildlife sanctuaries
Some leading National Parks and sanctuaries:
The Dachigam Wildlife Sanctuary
Jim Corbett National Park
The Sunderbans Wildlife Sanctuary
Manas Wildlife Sanctuary
Kaziranga National Park
Ranthambore National Park
The Keoladeo Ghana Bird Sanctuary
The Sasan Gir National Park
Kanha National Park
Periyar Wildlife Sanctuary
The concept of Biosphere Reserves was launched in __________ as a part __________________ Programme.
1975; UNESCO’s Man and Biosphere
A biosphere reserve should have following components
- core zone
- buffer zone
- transition zone
The fully protected and natural areas which is least influenced by human activities. This area is under legal protection and entry is only allowed with permission for some specific purpose. Destructive sampling for scientific investigation is not allowed.
core zone
This surrounds the key areas which keeps a wide range of resource use strategies, and activities related to research and education.
buffer zone
The outermost region of biosphere reserve which is characterised by the active involvement of local people reserve management. In this area activities like settlements, cropping, forestry, recreation and other economic activities which are in harmony with biodiversity conservation are allowed.
transition zone
About _______of biosphere reserves have been recognised throughout the world in 120 countries and have been included in the ______________
651; World Network of Biosphere Reserved
a traditional strategy for the biodiversity protection mostly practiced in India and in some of the Asian countries. These are the small forest patches protected by the tribal communities due to some religious belief. There is no protection of sacred groves through federal legislation. These are either protected by the related communities or some NGOs working with villagers.
sacred grove or sacred forest
generally used to safeguard populations that are potentially under threat and need to be collected and conserved in gene banks in form of seeds, live plants, tissues, cells and/or DNA materials. The principal aim of ex-situ conservation is to maintain seeds and other germplasm materials alive as long as possible and to reduce the frequency of regeneration that may cause the loss of genetic diversity.
ex-situ conservation
a place where plants are grown and displayed for the purposes of research and education.
botanical garden
The botanical gardens which are specialized in trees are also called as
arboreta
The main objectives of botanical gardens are:
i. Ex-situ conservation and propagation of important threatened plant species;
ii. Serve as a centre of Excellence for conservation, research and training; and
iii. Build public awareness through education on plant diversity and need for conservation.
are essential for ex-situ conservation and preservation of genetic resources.
gene banks
- Located in New Delhi, NBPGR plays a crucial role in preserving seeds of both wild species and cultivated plant varieties.
National Bureau of Plant Genetic Resources (NBPGR):
- Located in Lucknow, Uttar Pradesh, this institution maintains stocks of genetic material for various fish species.
National Bureau of Fish Genetic Resources:
involve storing dried seeds at low temperatures.
Seed preservation techniques
The longevity of seeds is influenced by factors like
temperature, seed moisture content, and relative humidity
bearing plants and those that are clonally propagated are conserved as live plants in field gene banks.
Recalcitrant seed
a technique that involves preserving living tissues at extremely low temperatures, typically around -196ºC, using liquid nitrogen.
This method effectively suspends mitotic and metabolic activities in the preserved tissues.
Cryopreservation
Benefits of Cryopreservation
- long-term and cost-effective conservation of plant genetic resources.
- This includes the preservation of species with recalcitrant seeds, which would otherwise be at risk
Applications of Cryopreservation:
Cryopreservation has been successfully applied to various plant components, including meristem, zygotic and somatic embryos, pollen, protoplast cells, and suspension cultures
- This technique has proven effective in preserving a wide range of plant species.
Species with difficult-to-store seeds or those that can only be clonally propagated can be conserved through biotechnological methods, as suggested by
Engelmann and Engels
Regeneration Process and Genetic Erosion
- Regeneration is a critical step and a major challenge in gene bank management.
- It is during this process that there is the highest probability of genetic erosion.
- Genetic erosion can be monitored by collecting information on genetic composition and spatial genetic structure.
are aimed at improving understanding, skills, and influencing behavior related to conservation.
Education and Awareness
involves enhancing the knowledge and skills of students in formal degree programs
Formal Education
focuses on enhancing knowledge, skills, and information exchange for practitioners, stakeholders, and relevant individuals
training
Raising environmental awareness and providing information to the public through various media.
Awareness and Communications
extend to actions aimed at developing, changing, influencing, and implementing formal legislation, regulations, and voluntary standards related to conservation.
Law and Policy
Efforts to promote global conventions on biodiversity, such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).
Global Legislation
Advocacy for or against government laws at the national level, such as the U.S. Endangered Species Act.
National Legislation
- Involvement in state or provincial ballot initiatives related to conservation.
- Providing data and information to state policy makers to inform decision-making.
State/Provincial Legislation:
- Development of local zoning regulations to ensure responsible land use.
- Implementation of countryside laws and species protection laws to safeguard local flora and fauna.
Local Legislation
Creation of tribal laws specific to indigenous communities to protect natural resources and biodiversity on tribal lands.
Tribal Legislation
