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.