What is one major environmental benefit of landscape horticulture?

The environmental benefit that stands out is the improvement of air quality through the processes facilitated by plants. Plants play a crucial role in photosynthesis, where they absorb carbon dioxide and release oxygen, significantly enhancing the composition of the atmosphere. Additionally, many plants can trap particulate matter and filter pollutants, which further contributes to cleaner air in urban and rural environments alike. This is essential for public health and mitigating the effects of pollution.

The other options, while they have some relevance to environmental discussions, do not reflect a positive environmental impact of landscape horticulture. Increasing the demand for water can lead to resource depletion, accelerating soil erosion undermines land stability, and contributing to urban heat islands exacerbates temperature increase in cities. Hence, the most advantageous choice is the improvement of air quality through plant processes.