Answer:
wastewater and fertilizer runoff
Explanation:
Factors such as temperature, pH electrochemical (redox) potential, and the transparency of air and water can affect the chemical and physical characteristics of ecological systems. This are as a result of activities like climate change, water contamination, and changes in water runoff.
Wastewater and fertilizer runoff causes low amount of dissolved oxygen in water, which affect biological communities and cycling thereby resulting in chemical and physical states changes.