Soil Testing and Other Questions

The natural world can be observed in two ways, qualitatively or quantitatively. Qualitative is related to the word “quality.” Qualitative observations describe phenomena that cannot be measured objectively. Examples are colors (each individual’s eye sees differently), flavors, or cuteness. Qualitative measurements are not easily repeated and can demonstrate bias based on emotions or culture.

Quantitative is related to the word “quantity.” These observations describe phenomena that can be measured objectively. This is the type of observation science is based upon. Examples are numbers of objects, temperatures, and distances.

Even when qualitative measurements are employed, accuracy of these figures depends on absence of human error and preciseness of measuring devices. There is no perfect instrument for measuring.  And of course, humans cannot see all of what is, anyway.

Give two examples of qualitative observation and two of quantitative observation.

Qualitative

1.  Doing a study to figure out people’s favorite type of food in a region.

2.  Doing a study to see what color swimsuits people wore to the beach that day to found out the most popular color.

Quantitative

1.  Taking annual monsoon precipitation levels.

2.  Measuring how many words per minute someone can type.

Dimensional analysis can be used to convert one type of unit to another using a fraction called a proportion.  This is a useful tool! Some references are based on the metric system, most often used in science, and other in the English system. If one has little experience with metric units of measurement, then how can critical thinking be applied? Having some familiarity with these conversions gives you confidence with interpreting data.

1.      Study these steps to use dimensional analysis to convert units of measurement from one type to another.

Step 1                                                                                   Example

Identify units to be converted.                                  Convert 10 miles to kilometers.

Step 2

Find equivalent conversion units.                             1 kilometer = 0.62 miles

Step 3

Set up proportions using multiplication                  10 miles   X   1 kilometer   =  ? kilometers

or division so you end up with the                                                  0.62 miles

units you want.                                                                                                                

Step 4                                                                                   10 miles   X    1 kilometer   =  ? kilometers

Solve and cross out matching unit labels.                                         0.62 miles                                

You will see an answer with the correct units.                                                        = 16.12 km

1.      Solve these conversion problems. Use help from the Internet, but you must show your work. You only need to solve one problem according to the first letter of your last name.

a.       A four-pound bass weighs how many grams?  1 gram = .002204462 pounds

4 pounds X 1 Gram    =  1814.501678867878  so a  4 pound bass weighs 1814.50 grams.

                   .002204462 pounds

b.      A forest snail travels at 5 inches in 2 minutes. Convert this to centimeters a minute.

5 inches x 2.54 centimeters = 12.7 centimeters then 12.7 centimeters/2 minutes = 6.35 centimeters

Therefore this forest snail moves 6.35 centimeters a minute.

You were offered a job and your potential supervisor said, “We can pay you in two different ways:  you can earn $6.00 a day with a $6.00 a day raise, or you can earn $1.00 a day with a 25% increase each day.  Carry out to at least 35 days to see the characteristic patterns.

1.      Answer these questions.

a.       Which earning strategy is the most profitable?                                                                          The most profitable would be earning one dollar a day with 25 % increase each day.   Overtime the percent increase turns out to be much more then the six dollar a day raise.

b.      Which would have seemed most profitable if you had stopped at six days?                                                                                                                                                         The most profitable in a six period would be the 6 dollars a day with a 6 dollar raise each day.

One of the first things a field ecologist will want to know about an animal or plant species is how dense is the population? Units of density are number of individuals or colonies, etc. per unit area or volume.

Another important question is: How are the organisms dispersed within the habitat? Dispersion is the pattern of distribution in space.

In most cases it is impossible, because of the time, effort or money involved, to count every individual or plot their location on a map. If we did so, it would be a census. So it would be useful if there were some way that we could get an accurate representation of some spatial characteristics of the population without having to map every organism.

By sampling the population we can do this, but the sampling must be done properly, if we want our representation to be valid. To insure an adequate representation, some guidelines must be followed.

Choosing Sample Sites: Random vs. Haphazard

Experimenter bias in sampling is a common hazard and must be continuously guarded against. For example, “It’s late, and this rock is too hard to look under, so it wouldn’t hurt to sample under this smaller rock.” To obtain an unbiased estimate of the population, sampling should be done at random, which means the sampling should be conducted in such a way that the probability of each individual being selected in the sample is the same. There are several ways of insuring this criterion is met or at least closely approximated.

Random numbers are series of numbers such that the chance of selecting, any number is equal at any point in the sampling procedure. If the random numbers can be assigned to organisms or to locations in the habitat, they can be used to select the sample from the population. A fast and simple method is to use a random number table. You can use the numbers in this type of table to select sampling positions (e.g. paces along a trail, GIS coordinates, termite holes in a wall that you have numbered etc.). Most calculators and spreadsheet applications also have random number generating functions.

A person might think that they can make up random numbers and/or sample “randomly” without use of some randomizing method. This rarely works to produce random numbers or a random sample. Samples determined by making up numbers are termed “haphazard.”

Commonly Used Methods for Spatial Sampling

There are three general types of sampling methods used to select individuals from a spatial population—quadrats, transect lines, and plotless techniques. In this lab, we will use the quadrat and transect.

1.      A quadrat is a frame (usually a square or a circle) of known area used to isolate part of the population of interest. This subset will comprise one sample. The size of quadrat selected is determined by features of the organisms in the population to be sampled. A postage stamp-size quadrat might work well for mites on a leaf but will be hard to use on elephants. The use of a quadrat is very simple. It is placed randomly in the sampling area (the habitat of the species of interest), and all the individuals within the quadrat are counted and/or measured.

Exactly what the sampling area is, how its limits are determined, and how the quadrats are placed, are all very important points in using this method. Quadrats are most useful when the area is fairly uniform and movement within the area is easy.

Determining density from quadrats may seem straightforward, but you must be aware (and should investigate as part of the exercise) how quadrat size and number of samples can influence your results.

1.      The transect method is most useful when the area to be sampled is zoned in some way or has some sort of gradients running through it. Think of a shoreline or the vegetation running up the side of a mountain.

Here is how it works. A transect line, often in the form of 100-meter measuring tape, is stretched along a randomly selected zone. Points along the line are selected. For our purposes in this exercise, the points are wherever the tape intersects a any part of a species. 

Density and Dispersion Patterns

The number of individuals per unit area is termed the density and it is described as  trees per acre², moose per km², zooplankton per m³, etc. Dispersion is the pattern of the distribution of organisms in space. There are three basic dispersion patterns: random, clumped, and regular.

A random dispersion pattern means that there is an equal probability of an individual occurring at any point in the habitat. Clumped dispersion patterns are those where the presence of one individual increases the probability of finding another one near by. Regular dispersion, indicated by more even spacing that would be predicted by a random dispersion, may suggest territoriality or some limited resource.

Sample Size

How many samples will you need to take before you are confident your estimate of density or dispersal reflects the true situation? Clearly, the larger the sample the better, but things like time, effort, and money also enter the picture. In this lab, you will look at two.

Sampling

Materials

· Relatively natural outside area with a good number of different kinds of plants. A garden, field, or trail. Use a flowerbed or garden in a pinch.

· Sun protection and water

· String in 16.2-meter length. Two-tenths meter is allowed for making a knot, details below.

· Other objects or more string to delineate subdivisions of your quadrat

· Numbers to draw from “hat” or random number calculator. See below.

 

1. Visit your natural area and choose a site in which you can situate a 4-meter by 4-meter quadrat.

2.      Take a photo of your site.

3.      Form your quadrat by tying the ends of your string together and forming it into a 4-meter by 4-meter square over your area.

1.      Subdivide the quadrat in to 16 equally sized squares. To do so, line up stones, lay down more string, place flags of paper or cloth, or other markers to make these boundaries like these. This is how your quadrat should look on the ground. Each square is about 1 m x 1 m.

Your quadrat will not be nice and straight like this. There will be lines of stones or flags of cloth to delineate the internal squares.

It may look more like this:

1.      Take a photo of the site with the quadrat in place.

1.      Draw this same arrangement on a sheet of paper.

1.      Write numbers 1 to 16 on small pieces of paper. Put them in a container (“hat”) so you cannot see them. Draw 8 numbers. These numbers correspond to the 1-meter squares you will count the number of species in. Write your random numbers here. You will only count species in these smaller squares.

1.      In each of these randomly selected squares, count and record the number of different kinds of species (species richness) the string intersects. Do not count the number of individuals of each species.

How can you determine the different species? Give them a common name you invent (or use one you know) and make sketches, so you can keep track of what you find. For example, Tiny Plant With Yellow Flowers or Spiny Leafless Shrub.

Blades of grass, spikey leafed plant, smooth leafed plant and rough leafed plant.  Four different specie varieties.

 

Table 1.

Random Numbers                                                                         Number of Different Species

2	2
5	3
16	3
15	4
10	3
7	2
6	1
3	2

1.      Record dispersal patterns observations.

    The most apparent dispersal pattern was definitely random, there was no rhyme or reason and many of the plants appeared to need their own space to grow.  Those clumped together were a lot smaller than the big ones.

1.      Answer these questions.

a.      This exercise did not require random sampling to choose your site. State how you chose your site, and explain any biases you discovered in yourself while doing so.

     I choose my site based on my hope to find a variety of plant diversity as I do not have much variety anymore in my yard I chose the side where a different variety of live was growing then just grass.

b.      Describe the differences in the number of species using each method. Which one seems to “capture” the scene the best? Remember we are not trying to get the most but a representative sample.

    The best method is the quadrant method because it allowed a better selection of the species and a more accurate representation.

c.       Discuss what you would change for either method to determine a more accurate species count (not to get more species!)

    I think the quadrant method is limited by the size of the quadrant, but this limitation wasn’t applicable to my study because I didn’t have any plants or vegetation that didn’t fit in my quadrant.  If I was in a different area trying and there was a huge tree in one of my quadrants it would throw the whole thing off.

A.      Soil Testing

· Soil samples taken from two different sites

· Rapidtest Soil Test Kit

· Trowel, small shovel, or spoon for collecting soil

· Collecting jars or bags

Procedure

1.       Collect soil and describe location of soil.

I collected dirt from quadrant 15 and quadrant 8 of my test site both of which numbers I decided randomly.

2.       Take 2 photos of the process of soil testing.

Mix of the two types of dirt I used to see difference

 

Table 2

                                   Location                     N level/rating    P level /rating      K level/rating     pH level/rating

Sample A	2	3.5	4	7.5
Sample B	0	1	4	7.5

Process of soil testing and element containing tests

a.       What is soil made of?               

 Soil is made up of rock, clay, dead organisms, air, water, mineral, organic matter and various other things.

b.       What nutrient (chemical cycles) are related to soil formation? Give two specific examples.      They are part of two main chemical process which are decomposition the break down of organisms and the nutrient supply for various living organism such as plants.  Soil contains decomposed life and returns it into new life.

a.       How do you know what soil is best for what plants?                                                                                                                                                              By using a testing kit such as we did in the lab it contains information for those of us who may not know the best soil for our plants.  A good soil has high levels of Nitrogen, Phospurus and Potash.  It should also have a relatively medium to medium high PH level such as 5 to 7.

b.       What would the world be like if there was no soil?                                                                                                                                                                  I am pretty sure we would have no life on Earth except maybe in the oceans if there was no soil because soil is the basis of life on land.

c.        Why is soil important?                                                                                                                                                   It helps decompose dead animals/plants and use there remains to create new life by providing nutrients for living things.

d.       Why do you think it is important to test soil for pH, N, P, and K? In other words, what is the role each of each of these elements in plant growth or health? Remember to cite any sources.                                                                                                                                                                           I think it is important to know if you can grow plants on your soil because these elements are found in all living things making it important if you want to start growing something.  If it has these elements that help sustain life they must play a key part in the creation of life as well.

e.        How is soil type related to biodiversity?                                                                                                                                                       Depending on the region there can be different elements in different regions or places around the world.  The different nutrients in the soils around the world can create diversity because overtime the environment has grown based on what was available in the soil which causes different variety's of plant and animals.

f.How does soil type relate to biomes?                                                                                                                                                Certain biomes contain different soil with more common aspects of nutrients.  For example a desert in America could have similar nutrients to a desert in Africa because they are both sandy and have similar landscapes.  They may be slightly different, but could contain the same nutrients.

g.        Name 3 factors that might cause soil type to change over time in short term (days to hundreds of years) or long (geologic) term.                                                                                                                                                                            Three factors could include long term drought, chemical pollution and crops being constantly grown on the soil.