Soils Are Developmental Sequences, Distinctive Layers That Develop in Place

question 6

Multiple Choice

Soils are developmental sequences, distinctive layers that develop in place. B horizon refers to

• A) the topsoil layer where organic material and rock undergo chemical and mechanical decomposition.
• B) the layer where clays accumulate as rainfall and snowmelt transport them downward.
• C) a mineral horizon consisting of parent material.
• D) the cultural layer between the topsoil and mineral horizon.

---

Definitions:

Natural Experiment

An experiment in which nature, rather than an experimenter, manipulates an independent variable.

Community Cohesiveness

The quality of forming a united group, characterized by mutual support, shared values, and a sense of belonging among community members.

Double-masked

In medical studies, a trial in which neither the participants nor the researchers know who belongs to the control group and who belongs to the experimental group.

Placebo

An inert substance or treatment which has no therapeutic effect, used as a control in testing new drugs.