Grade 4 Standard 6.0 Environmental Science Clarification: People affect the environment. But the environment also affects people. This indicator and objective investigate how Maryland’s environment determines how humans live. Climate and soil type determine the kinds of plants that grow naturally or are cultivated in an area. Plants, in turn, determine the distribution of animal populations. The abundance and type of natural resources used by Native Americans, European colonists, and now by us today, determines settlement patterns, agricultural products, and industry. This indicator can be easily integrated with Social Studies Standard 3.0 Geography. B. Environmental Issues 1. Recognize and describe that people in Maryland depend on, change and are affected by the environment. Objective 1: Identify and describe that human activities in a community or region are affected by environmental factors Presence and quality of water Soil type Temperature Precipitation The essence of this indicator is that there is, or can be, a cyclical effect when humans make decisions or take actions. Human activities obviously take place within the context of the local (and sometimes global) environment and those actions, deliberate or otherwise, change the existing situation. The change can be for “better” or “worse” or be debatable. In either case, the changed environment will become part of the new cycle in which the humans who made the change must live. Theoretically, everybody should be trying to make the world a better place, if for no other reason than it is self-benefiting. As educators we should hope that the decisions made and actions taken are done so from an informed position and also that improvements to the environment more than balance any negative effects. Presence and quality of water: One of the requirements for any life is the sufficient supply of usable water. Desert conditions make life more difficult for people (though not impossible; i.e., Las Vegas) and too much water (New Orleans) can also be problematic, but procuring, using and getting rid of water is a daily requirement. Human activities can pollute community water supplies and add to community costs. Water Treatment Plants represent human efforts to speed up the natural water (cleansing) cycle. Soil type: Land is literally the foundation upon which humans build anything. Land is zoned by people to restrict or allow specific kinds of constructions or activities and part of the zoning process includes an analysis of the soil ingredients (clay, sand, silt and associated chemicals). The efficient growing of plants requires a knowledge of the physical, chemical and biological make-up of the local soil. In large scale gardening or farming humans should be aware of the changes affected in the soil by the annual production of specific plants or crops. Particularly in agriculture, the harvesting of a crop also means the removal of the nutrients that made that crop. Constant removal without replenishment is not sustainable. Temperature: Extremes of cold or hot temperatures usually restrict human activities in a region. Most people are not interested in modifying the environment beyond certain limits (normal air conditioning and heating requirements) just to take up residence or work in a particular location. Like all living things, people have optimal conditions (which includes a temperature range) that will determine their ability or willingness to live somewhere. Areas that have close to optimal temperatures tend to attract large numbers of people (the demographic trend in the U.S. is toward southern states) and that increase in population can cause environmental problems. Regional temperature can also affect the other factors under discussion here; water availability, precipitation and soil characteristics. Precipitation: Rain (the receiving half of the water cycle) determines whether plants will grow or be washed away, whether erosion needs to be controlled, whether dams need to be built, whether streams will remain in their banks, whether a vacation will be successful or not and hundreds of other conditions that affect human activities. So far, humans are unable to control the weather, but it needs to be considered every day. The other large factor to consider is that precipitation originates in the atmosphere and therefore ingredients (pollution) in the air can affect the quality of that precipitation. It would be better for the environment if human activities did not contribute to acidic rain because, as already mentioned, what goes around, comes around.