Chapter 2, Problem 1CR

To determine

The controlled scientific experiment that was carried out in the Hubbard Brook Experimental Forest.

Answer to Problem 1CR

Studies that deal with the ecological effects of the environment are the controlled experiments that were conducted in the Hubbard Brook Experimental Forest. It includes the measuring of the volume and nutrient content of water when the forest was flourished with trees and the measuring of same after the deforestation. The researchers who conducted on the deforested valley showed a low volume and less dissolved nutrients in the water.

Explanation of Solution

The controlled experiment was carried out to examine the harmful environmental effects that occur when the trees in a particular area were cut down. It involves identification of the change in key variables such as the loss of water and amount of soil nutrient after deforestation and comparing the water loss and nutrients of soil from a control site (area of uncut trees) with experimental site (deforested area).

To carry out this experiment, the researches constructed a V-shaped dam of concrete across the creeks at the base of each forest in the Hubbard Brook Experimental Forest that is located in New Hampshire. The dam was built in such a way that the entire surface that leaves the forest valley had to cross the dam and thereby measure the volume and amount of nutrients dissolved in water by the researchers.

Initially, researchers measure the volume and dissolved nutrients of the water in the control site. The results indicated that the undisturbed mature forest was resourceful at storage water and holding chemical nutrients in its soils.

Later, an experimental area was set up by the researchers by cutting down the trees and shrubs in the valley and spraying herbicides to prevent the further growth of plants. The researcher examined the outflow of water and nutrients in the experimental site with data from the control site for three years. The results showed that the volume of water flowing from the deforested increased 30-40%. This surplus water flows over the ground quickly, erodes soil, and removes dissolved nutrients from the topsoil. Overall, the loss of key soil nutrients from the experimental forest was six to eight times than in the nearby uncut control forest.