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| What Is Environmental Sampling? |
Have you ever wondered how scientists know where certain animals live or how they make those maps that show the home ranges of particular species? that kind of information is a result of what is known as mapping and zoning. scientists will go to a specific location such as a swamp or forest and try and find all of the different species that live in the habitat.
Once they have gathered all the data they then plot the data onto maps for future use. scientists known as ecologists study the variety of different species in an area by measuring the distribution. so where they are and their population so how many there are in order to try and understand the different connections between the different organisms and how environmental factors affect living things.
Imagine we are walking along a rocky shore in England and we notice that there are lots of different species at different heights on the shoreline. we want to investigate but we should count every single species along the shoreline. how long do you think that would take of course it would take too long. instead, we sample a small section of the area which gives us a representation of the whole area.
Sampling allows ecologists to cover all the different areas within the habitat without having to record the entire habitat. this enables ecologists to measure the biodiversity of an area record data on abiotic factors and even get a good estimate of the complexity of a local ecosystem in comparison to other sampling sites.
On the rocky shore, we use a tape measure, and one of these is a quadrant. quadrants are square frames of a known size such as one meter squared. they could be like this or like this they're used to monitor sedentary organisms. so organisms like plants and fungi and some animals such as barnacles do not move about from one place to another. perfect for us to study the shoreline.
At low tide, we place a tape measure perpendicular from the sea up the shoreline like this. this is called a belt transect. we have subdivided the shoreline into zones kind of like a grid system to ensure that we sample the entire area fairly and don't get biased data.
At regular intervals along a pile transect, we place the quadrants down and count the percentage cover of each different species found. this gives us information about how the population of different species changes as we move up the rocky shore. from our data, we can clearly see that different species can survive in different areas or zones along ashore according to the different abiotic factors.
But ecologists don't just study rocky shores they use a variety of different environmental sampling techniques to investigate lots of different ecosystems. here are some more examples of sampling techniques. this is a puter that is used to catch small insects. here is a sweep nest these are used in areas of long grass to catch organisms. they can also be used in ponds.
Pitfall traps are used to catch small crawling insects and animals. they can be set up and left overnight to catch nocturnal species for example to investigate how many beetles are in the area of a woodland or you might choose quadrants to investigate how many daisies there are in a field but this time you would use random sampling instead of a transect method we saw before.
Once all the data has been gathered the information is plotted using a geographic information system or gis. software to create range and habitat maps. the maps can also be used to study things like ecotones the boundary between two habitat types species dispersal and the migration patterns and even determine when a species was found in a new area.
While it may not sound like the most glamorous work mapping and zoning is a crucial part of understanding ecosystems and the organisms that live within them. from this article, you should now know that ecologists are interested in the distribution of organisms within habitats and the use of transects and quadrants and other sampling methods to collect quantitative data.
They take samples because counting every member of each organism within a habitat would be far too time-consuming. the samples are carefully planned to ensure they are random and representative of the whole ecosystem and the sampling techniques used depend on the habitat and the type of organisms present.