• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
community
community

... • Keystone species exert strong control on a community by their ecological roles, or niches. • In contrast to dominant species, they are not necessarily abundant in a community. • Field studies of sea stars illustrate their role as a keystone species in intertidal communities. ...
Print test
Print test

... many years. Since the island is small, the lineage of every bird for several generations is known. This allows a family tree of each bird to be developed. Some family groups have survived and others have died out. The groups that survive probably have ...
Endangered and Threatened Species in Kansas
Endangered and Threatened Species in Kansas

... farming practices that affect these species, or other human activity having an impact on these species or their habitats within Kansas. In addition, the provisions are not to be construed to infringe on the authority of the Kansas Department of Wildlife, Parks and Tourism or any citizen participatin ...
Human Impact On the Earth
Human Impact On the Earth

... Although DDT was suspected, the levels to which the birds had been exposed were nowhere near high enough to have killed them. But when the bird's bodies were analyzed, they were found to have up to one million times the concentration that was present in the sprayed water. This led to the discovery o ...
Intensive surveys
Intensive surveys

... semi-quantitative results must be taken in a random way. In such a case one sample is insufficient and the number of samples must not defined. ...
Enrichment and rehabilitation in the permanent forest estate
Enrichment and rehabilitation in the permanent forest estate

... and the rural economy Techniques for rapid soil stabilisation in hill forests (approximately  of the area affected) are becoming increasingly important as these forests are logged. Project results offer effective soil management options through restorative and productive plantings of proven speci ...
PPT Slide - Tennessee State University
PPT Slide - Tennessee State University

... Similar life cycle and food requirements Initially, each species won twice Using this facility, Pimentel showed that two species coexist for 70 weeks. ...
Notes Chapter 21 Community Ecology
Notes Chapter 21 Community Ecology

... 2. Explain how competition can affect community structure. A. Most competition does not involve fighting 1) Some competing species never encounter one another: they interact only by means of their effect on the resource in question B. Competition Research 1) Competition results from fundamental nich ...
Dusky hopping mouse - Northern Territory Government
Dusky hopping mouse - Northern Territory Government

... 1999). The species was formerly found across a much wider range that stretched as far west ...
Factors That Affect Climate
Factors That Affect Climate

... an important role in regulating the population sizes of mice, voles, and other small mammals ...
1981
1981

... but it cripples and kills the native finches and mockingbirds which have not developed immunity. While it is cheering to record that some ferals have failed, the CDRS is highly conscious of the fact that too many have succeeded in the past and that there is a constant threat for the future. C.S. Elt ...
chapter6
chapter6

... little or no effect on the other ...
Understanding Our Environment
Understanding Our Environment

... Commercial Products and Live Specimens  Wildlife smuggling is very profitable. - Leopard fur / Rhinoceros horns  U.S. Annual pet trade in wild species: - 2 million reptiles - 1 million amphibians and mammals - 500,000 birds - 128,000,000 tropical fish  Cyanide released above coral reefs. ...
EAT_working_for_water
EAT_working_for_water

... Initial studies focused on the economic consequences of water loss. The scope then expanded to include losses incurred in tourism, natural resource harvest, pollination services, option value, and existence value. Recently studied have also included the effect of invasions on fires. ...
Francis Ming Pong Choi
Francis Ming Pong Choi

... University of British Columbia (Dept. of Earth and Ocean Sciences) Sept ’09 – Aug ‘11 Graduate researcher  Conducted the first Pacific and Atlantic intertidal assessment of non-indigenous species in Canada  Identified over 200 intertidal invertebrates and algae  Created a novel statistical standa ...
Control and eradication
Control and eradication

... Change Vector Analysis (CVA): Change measure Difference in pixel intensity. (100% from total absorption to total reflection) Threshold for no change: 17% ...
MediterraneanBasin
MediterraneanBasin

... protection of natural resources. Nonetheless, today, protected areas only cover4.3% of the total land area. In recognition of the valuable, but extremely threatened, natural heritage of the Mediterranean Basin, most countries within the region are planning significant expansion of their protected ar ...
SISI questionnaire
SISI questionnaire

... - INNS control – Himalayan balsam pulling ...
Ecology: Lecture 1
Ecology: Lecture 1

... correlated. The two species have been demonstrated to require the same limited resource and/or one interferes with the other’s ability to acquire resources Removal of the “superior” competitor results in movement of the “inferior” competitor into the now unoccupied region. It is really the presumed ...
Answers to Mastering Concepts Questions
Answers to Mastering Concepts Questions

... Macroevolutionary events are large-scale evolutionary changes, such as the evolution or extinction of a species, that typically occur over long periods of time. Small-scale microevolutionary events occur over shorter time periods, such as the changes in allele frequencies that occur each generation ...
An overview on ecosystems: Ecosystems Terrestrial vs aquatic
An overview on ecosystems: Ecosystems Terrestrial vs aquatic

... significantly different from the overall regime (e.g. a south-facing slope or sheltered ravine, proximity to a creek, the shade of a rock or tree) Similarly, a given aquatic site may have temperature, light or nutrient conditions that are significantly different than the open water (e.g. upwellings ...
Evolution occurs in patterns - rosedale11universitybiology
Evolution occurs in patterns - rosedale11universitybiology

... finches, the descendent species are still finches but adapted to a wide range of environments. b. Allopatric speciation – a starting population is geographically divided and over time the separated groups can evolve into different species. c. Sympatric speciation – a new species forms beside the anc ...
Fish Fauna of the Great Lakes
Fish Fauna of the Great Lakes

... interactions among species?  Effects of introduced species: – rainbow smelt and alewife - planktivores • compete with native planktivores • prey on larvae of native fish species • prey on and compete with each other! ...
Midterm Final Review
Midterm Final Review

... • Territorial behavior parcels space and resources ...
What Limits the Size of a Food Chain?
What Limits the Size of a Food Chain?

... Dynamic Stability Hypothesis • Top predators must be able to recover from environmental shocks that can reduce food supply all the way up the chain. • If they chain is long it takes longer for the top predators to have shock be suppressed. ...
< 1 ... 258 259 260 261 262 263 264 265 266 ... 372 >

Introduced species



An introduced, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are called invasive species. Some have a negative effect on a local ecosystem. Some introduced species may have no negative effect or only minor impact. Some species have been introduced intentionally to combat pests. They are called biocontrols and may be regarded as beneficial as an alternative to pesticides in agriculture for example. In some instances the potential for being beneficial or detrimental in the long run remains unknown. A list of some introduced species is given in a separate article.The effects of introduced species on natural environments have gained much scrutiny from scientists, governments, farmers and others.
  • studyres.com © 2026
  • DMCA
  • Privacy
  • Terms
  • Report