Which of the following was a result of the Hubbard Brook watershed deforestation experiment? (A) Most minerals were not recycled within the intact forest ecosystem. (B) Calcium levels remained high in the soil of deforested areas. (C) Deforestation decreased water runoff. (D) The nitrate concentration in waters draining the deforested area became dangerously high.

Verified step by step guidance

1. Identify the key terms in the question: Hubbard Brook watershed deforestation experiment, minerals, calcium, water runoff, nitrate concentration.
2. Understand the context of the experiment: The Hubbard Brook experiment was designed to study the ecological effects of clear-cut deforestation on a watershed.
3. Analyze each answer choice in relation to the effects of deforestation observed in similar ecological studies: (A) Consider if intact forests typically recycle minerals, (B) Evaluate how deforestation might affect soil nutrients like calcium, (C) Assess the impact of tree removal on water absorption and runoff, (D) Examine the potential changes in water quality, specifically nitrate levels, following deforestation.
4. Recall from ecological studies that deforestation often leads to increased runoff due to reduced vegetation and root systems which normally absorb water, and consider how this might affect nutrient levels in the water.
5. Conclude by linking the increased runoff and reduced nutrient absorption by plants to potential changes in water quality, such as increased nitrate concentrations.

Key Concepts

Hubbard Brook Watershed Experiment

The Hubbard Brook watershed experiment was a groundbreaking ecological study conducted in the 1960s that investigated the effects of deforestation on nutrient cycling and water quality. Researchers compared deforested areas to intact forest ecosystems, measuring changes in water runoff, nutrient levels, and soil composition. This experiment provided critical insights into how forest ecosystems function and the consequences of human-induced changes.

Nutrient Cycling

Nutrient cycling refers to the movement and exchange of organic and inorganic matter back into the production of living matter. In forest ecosystems, nutrients like nitrogen and calcium are recycled through processes such as decomposition and uptake by plants. The Hubbard Brook study highlighted how deforestation disrupts these cycles, leading to nutrient loss and increased concentrations of certain elements, such as nitrates, in water systems.

Impact of Deforestation on Water Quality

Deforestation significantly impacts water quality by altering the natural filtration and nutrient retention processes of forest ecosystems. When trees are removed, there is less vegetation to absorb and utilize nutrients, leading to increased runoff and higher concentrations of pollutants, such as nitrates, in nearby water bodies. This can result in harmful effects on aquatic life and overall ecosystem health, as observed in the Hubbard Brook experiment.