Chang, Baoxin (2020-06). NUTRIENT AND IRRIGATION MANAGEMENT FOR ENHANCING TURFGRASS ECO-BENEFITS. Doctoral Dissertation.
Turfgrass is a subgroup of grass family, which plays a significant role in modern urban landscapes. While homeowners have traditionally installed and appreciated a landscape of predominantly turfgrass; in recent years many municipalities have begun to offer rebate programs which incentivize removal of turfgrass areas and conversion to alternative 'water-efficient' landscapes, with the goal of reducing outdoor water use. Although scientists have provided evidence that turfgrasses have positive impacts on many environmental concerns, there are still gaps to fill when determining the real role of turfgrasses in future urban societies. To better understand this, one field study was conducted to evaluate the environmental impacts and runoff dynamics after urban landscape conversions. Hereseveral environmental impacts were compared among lawns and water-efficient landscapes (Chapter 5). Challenges are also being faced by many turfgrass managers; for example, as rapid population growth continues in urban areas, water conservation has become a key priorityy for many municipalities. Given this problem of water shortage, lower quality water sources are being used for irrigating turfgrasses, particularly on city owned properties and parks. It is importance therefore in understanding the effects of irrigation chemistry on the efficiency og turfgrass N uptake. Addressing this concern, two greenhouse studies examined interactive effects of several soluble N sources and irrigation water with different salinity levels on turfgrass performance and N uptake efficiency following both foliar and root N fertilization (Chapters 2 and 3). Wetting agents have been widely used in the turfgrass industry for ameliorating hydrophobic soil conditions and improving water use efficiency. However, limited information is available regarding the potential benefits of wetting agents on fine textured soil lawns where wettable soils are commonly found. A field study was conducted to evaluate the potential for wetting agents to improve turf quality, as well as to reduce runoff losses of water and nutrients from St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] lawns (Chapter 4). turfgrasses, particularly on city owned properties and parks. It is importance therefore in