Pick an anthropological activity which alters the abiotic features of a freshwater ecosystem and describe the effects this behavior has on the abiotic features for the zones of this ecosystem.

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One anthropological activity that alters abiotic features of a freshwater ecosystem is archaeological digs. This type of activity near freshwater ecosystems can cause disturbances to water levels, pH balance, visibility, toxicity, and more. Even a scientific study to observe these attributes would affect abiotic factors in the environment.

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Anthropology has been called "the science of humanity." It studies human beings and focuses on what "makes us human." Anthropologists will study human biology, culture, society, and more in an effort to see what we have in common with each other, other species, and to see what makes humans unique. Anthropology is a wide field, and it is often divided into smaller sub categories. Those four branches are archaeology, biological anthropology, cultural anthropology, and linguistic anthropology.

Abiotic factors of an ecosystem are non-living factors that are a part of that ecosystem and affect the ecosystem. Things like temperature, pH levels, rainfall, pressure, wind amounts, currents, humidity, soil composition, and/or oxygen levels are all abiotic factors.

In one sense, an anthropologist can't study or do anything within a given ecosystem without affecting it in some way. This is what can make scientific investigations so difficult. A researcher's very presence can change something within the study itself or within the area (in this case an ecosystem) being investigated. This is called the observer effect; however, I believe that this question is looking for a much more concrete example.

Let's say that the anthropologist is an archaeological anthropologist. This person is working on an archaeological dig near a lake. The dig itself will change the water runoff pattern, which effects the larger water cycle. Perhaps the dig causes more runoff to enter the lake. This might cause lake levels to rise. Additionally, the extra runoff might be carrying more sand, dirt, silt, etc., and that may cause changes in water visibility. That could adversely affect existing predator-prey relationships or even the amount of light that is capable of penetrating to specific lake depths. All of those changes exist in addition to toxins that the anthropological activity might introduce to the lake. If any of the nearby equipment is leaking gasoline or oil, those substances can end up in the lake and pollute the water.

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Pick an anthropological activity which alters the abiotic features of a freshwater ecosystem. Focus on lakes. Describe the effects this behavior has on the abiotic features for the zones of a lake. Describe which organisms may be affected. Describe how these abiotic features are tested by an ecologist.

While the field of anthropology encompasses the study of non-human primates, it addresses human behavior and its impact on the environment. Two interrelated human activities crucial to food production have significant impact on lakes: agriculture and raising animals. The abiotic features of a lacustrine freshwater ecosystem include water and the soil within and around the lake.

The overall problem of Nonpoint Source Pollution (NPS) has effects on a lake’s abiotic features. According to the US Environmental Protection Agency (EPA), “runoff from farms is the leading source of impairments to surveyed rivers and lakes.” The most significant dimension is sedimentation, which results as soil particles wash off fields. This often decreases the amount of water that would naturally flow into streams and rivers. In addition, NPS is closely associated with chemicals used in agriculture. The use of petrochemical herbicides and pesticides leads to runoff. Following rainfall and snowmelt, the chemical residue moves from land into streams and rivers that feed into lakes.

Raising animals is also associated with NPS, especially through overgrazing; its effects include soil exposure, increased erosion, and the destruction of stream-banks and floodplains. Animal feeding also makes negative contributions, such as water contamination from manure entering water through runoff.

These kinds of pollution have notable impacts on abiotic features in all three lake zones. Salinization is one notable problem. Increased salt concentration may occur with the evaporation of irrigation water. Sedimentation-related runoff may make the water cloudy, reducing the amount of light available for photosynthesis, which in turn will reduce the amount of oxygen. These effects are significant in the littoral and limnetic or pelagic zones. Effects on the mineral content include increased phosphorus. Heavy metals also enter the water, causing long-term water pollution. Changes to lake-bottom soils, especially from sedimentation, affect the benthic zone.

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