Human activity
* All human activities depend on the world's land and water resource base
  - have an impact on the environment
  - take place somewhere, and have spatial and locational attributes
* All human activity depends on and arises out of connections between neurons
  - has an impact on the environment
* All human activity is an expression of the psyche
  - by nature determined by the egoism of the individual
  - carried on by means of the mind aided by the ten senses
  - subject to habitualization
* Every human activity has an economic dimension.
* Human activities affect all parts of the biosphere
  - biodiversity
  - ecosystems
  - environments
  - marine environments
  - nutrient cycling in ways that can be damaging to ecosystems
  - photosynthesis
  - predators
  - surface temperature
  - the environment in a number of ways
* Human activities alter aquatic ecosystems
  - many of the components of the earth's climate system
* Human activities alter the chemistry of rain water
  - frequency of both and, by so doing, greatly affect community structure
* Human activities are a primary cause of desertification
  - agriculture and, in the surrounding areas, hunting
  - dependent upon location
  - important in almost all ecosystems
  - largely responsible for the disappearance of loons from many lakes
  - mainly responsible for the increase of lead in the ecosystem
  - nature conservation, power generation, forestry, and agriculture
  - notorious for affecting sizes of natural populations
  - responsible for the increases in ground-level ozone in recent years
* Human activities are the main cause of acid rain
  - factors triggering desertification processes on vulnerable land
  - threats to local populations
  - major cause of current reef decline
  - principal cause of declining tiger numbers
* Human activities associate with growth
  - population growth
  - bring about changes in land cover, land use, and land management
* Human activities can accelerate environmental changes
  - the process of change
* Human activities can accelerate the rate at which nutrients enter ecosystems
  - of many natural changes
* Human activities can also affect soil structure
  - cause flash floods to occur
  - change the climate
* Human activities can alter the atmosphere
  - trophic status of a lake
* Human activities can be significant sources of indoor air pollution
  - the cause of turbidity as well
  - cause pollution of both surface and underground water
  - change the flow and reduce the usability of earth's resources
  - contribute to the frequency and intensity of some natural hazards
  - degrade the quality of ground water
  - disrupt or destroy delicate food webs
  - either deliberately or inadvertently alter the balance of an ecosystem
  - greatly accelerate the release of nutrients into the lakes and streams
  - harm dolphins
* Human activities can have a serious effect on the population
  - great impact on Hawaiian monk seal survival
  - introduce thermal pollution into streams in several ways
* Human activities can lead to nondepletive or depletive water use
  - water and air pollution, for example
  - negatively impact the water quality of streams
  - pollute the air and water
* Human activities can, deliberately or accidentally, change the equilibrium in ecosystems
  - inadvertently, alter the equilibrium in ecosystems
* Human activities cause degradation and destruction processes in the natural soil layer
  - dramatic changes in the environment
  - harmful reaction
  - or accelerate permanent changes in natural systems
* Human activities change aquatic environments and food webs in many ways
  - features
  - the physical environment and ecosystems
* Human activities consist of livestock grazing and cultivation
  - salt production and livestock grazing
  - contribute to the erosion and pollution of beaches
  - decrease biodiversity
* Human activities destroy bee habitat and forage
  - habitats
  - do affect climate
  - do, deliberately or inadvertently, alter the equilibrium in ecosystems
* Human activities enhance adaptive capacity
  - effects
* Human activities have a profound impact on the hydrologic cycle
  - rapidly growing rate of impact on the environment
  - an increasing effect on groundwater levels
* Human activities have have devastate effects
  - results
  - the potential to affect our fragile environment
* Human activities impact ecosystems on local, regional and global scales
  - environmental quality, which in turn impacts human health
  - the entire planet
* Human activities increase availability
  - inflict harsh and often irreversible damage on the environment
  - influence natural processes on and in the Earth
* Human activities lead to cascade effects
  - distribution
  - modify gas fluxes both directly and indirectly
  - play an important role in the formation of severe sandstorms
  - pollute the air, ground and water
  - related to livelihood and welfare measures generate waste
* Human activities result in productivity
  - water resources
  - resulting in habitat loss are the main threat to their survival
  - shape Earth's surface
  - threaten marine habitats at the ocean's edge
  - transform materials and energy into products and services
* Human activities yield benefits
  - economic benefits
* Many human activities change predator abundances either deliberately or unintentionally.
* Many human activities contribute P to surface waters
  - phosphorus to surface waters
* Many human activities have a significant impact on the nitrogen cycle
  - some potential to affect drinking-water sources
  - produce heat
* Most human activities affect biodiversity
  - climates
* Most human activities associate with growth
* Most human activities cause harmful reaction
  - destroy habitats
  - increase numbers
* Most human activities involve a degree of creativity
  - groups of people acting together in the same place at the same time
* Most human activities lead to cascade effects
* Most human activities result in productivity
* Some human activities affect behaviour
  - prey behaviour
  - responses
  - runoff
  - uptake
* Some human activities can damage a wetland without leaving clearly visible signs
  - influence local water vapor levels
* Some human activities cause deterioration
  - diseases
  - soil erosion
  - change equilibrium
* Some human activities contribute to degradations
  - depletion
  - land degradations
  - mortality
  - eliminate habitats
* Some human activities have coastal erosion
  - widespread effects
* Some human activities increase concentration
  - gases
  - the levels of aerosol in the atmosphere
  - involve burns
* Some human activities produce gases
  - greenhouse gases
  - provide food
* adds large amounts of dissolved and solid material to streams.
* alters the water cycle also.
* can also play an important role
  - alter water quality by many mechanisms
  - change living organisms and ecosystems
  - exacerbate the impact of climate change through the build-up of greenhouse gases
  - reduce the number of predators
  - release some of that mercury into the air, water and soil
  - significantly affect sand supply
* contaminates groundwater.
* continues to affect the biosphere.
* creates edges through development and agriculture.
* depends upon and, in that sense, reflects or mimics the workings of nature.
* does more than put a stress on elephants to find resources.
* generates a great deal of radio noise on a wide range of frequencies.
* has profound impacts on flooding
  - the greatest impact on the amount and quality of wildlife habitat in Illinois
* is an event
  - essential to improving and repairing the world
  - largely responsible for today's wildlife crisis
* is most likely responsible for climate warming
  - playing some part in food production variability
* is responsible for eroding the status of the crested toad
  - the rapid increase in atmospheric carbon dioxide concentrations
* is the fundamental cause of desertification
  - main reason why species are disappearing more rapidly
  - most significant process shaping the surface of the planet
  - primary cause of our environmental problems
  - very fast compared to a geologic timescale
* major cause of air pollution, much of which results from industrial processes.
* mediates a trophic cascade caused by wolves.
* place a stress on urban environments that green spaces help relieve.
* poses a great danger to the earth's atmosphere.
* produces more radio waves than the sun
  - ozone-forming emissions in many ways
* takes a heavy toll on young in nests.