HB HM Flashcards
Without management many habitats disappear, for example, in the UK, grasslands scrub over and eventually become…
deciduous woodland
A classic example of extreme habitat management is
Agriculture
Ecosystems provide essential services to people including…
clean water, food, pollinators, seed-dispersers, fuel, medicines and building materials - even oxygen!
Reasons to manage a site for wildlife include…
enhancing wildlife habitats, protecting species and habitats, avoiding disturbance, avoiding degradation, complying with the law or a planning condition, enhancing the aesthetic value of a site and enhancing the enjoyment and intrinsic value of a site for people.
What is habitat management?
the process of managing habitats for a particular purpose, usually to maintain a habitat as it is, or restore or enhance a habitat in order to increase species diversity.
Habitat Management techniques may include…
grazing, mowing, planting, scrub removal, controlled burning, tree thinning, pond clearance, removal of invasive species, protective fencing or scraping off fertile soils.
The main ecological processes you need to consider in habitat management are…
succession and disturbance
Succession is…
the natural process of change from an area devoid of life to a stable climax community
an area that is devoid of life - retreating glaciers or a volcanic eruption
primary succession
secondary succession
soils and the seed bank remain after natural disasters e.g. floods and fire. So the area is not devoid of life.
Climax community is linked to our location in the world…
latitude and climate, and the influence of the sea
Many habitats are present due to natural disturbance…
erosion and flooding in coastal, river and upland systems, by trees falling and deer grazing in woodlands
Human disturbance in land management includes… (6)
mowing, cutting, coppicing, burning, grazing and ploughing
The release and encouragement of a species in an area where it formally occurred but is now extinct
Re-establishments
An attempt to establish a species where it did not previously occur
Introductions
Reintroductions
an attempt to establish a species in an area where it had been introduced but the reintroduction has been unsuccessful
Reinforcement
attempting to increase population size by releasing additional individuals
the transfer of individuals from one site to another (boost population or save individuals which would otherwise be destroyed).
Translocation
Succession – the classical model – is a continuous unidirectional, sequential change in the species composition of a natural community. (5 stages)
Annual weeds – Herbaceous perennials – Shrubs – Early successional trees – Late successional trees
Self-driven succession that begins on newly formed substrates not occupied by any organisms and where no organic material is present – newly posed rock faces, alluvial deposits and glacial moraines is primary succession. Where vegetation cover has been disturbed by humans, animals or by fire, wind, floods is secondary succession.
Autogenic succession
Degradative succession
particular type of autogenic, primary succession: the colonisation and subsequent decomposition of dead organic matter
Serial replacement of species can result from external environmental factors, such as geophysical-chemical changes
Allogenic succession
What is a hydrosere?
Natural succession that started with open water (e.g. pond or lake)
Name 8 global biomes
Tundra, Taiga, Grasslands, Savanna, Deciduous Forest, Chaparral, Desert, Desert-scrub, Rainforest, Alpine