The key factors affecting soil fertility include organic matter content, nutrient availability, soil texture, and pH level. Organic matter enhances soil structure, promotes moisture retention, and serves as a nutrient source for plants. Nutrient availability, particularly of nitrogen, phosphorus, and potassium, is critical for plant growth. Soil texture influences water retention and nutrient exchange capacity, while pH affects nutrient solubility and microbial activity. Understanding these factors is crucial for developing effective management strategies to enhance soil fertility, promote sustainable agriculture, and support healthy ecosystems.