In an effort to conserve water, conversion of irrigated lawns to “water-saving” landscape designs are being promoted in urban areas. Different materials, with different radiative and thermal properties, are used to accomplish this. We conducted a field study where we measured reflected spectral irradiance, albedo, energy balance, and soil and surface temperatures of grass (GR), artificial turf (AT), decomposed granite (DG), and hardwood mulch (MU) to better understand how surface temperature is controlled in landscapes composed of these materials. DG had the highest albedo and a large fraction of the reflected solar energy was in the visible band. AT had the lowest albedo and highest net radiation of the materials we tested. DG was the most efficient material in conducting energy into the subsurface, whereas MU was the least. Both AT and MU concentrated most of their thermal energy in the surface, indicating poor ability to diffuse thermal energy into the subsurface. Latent heat flux was the major component of the energy balance of GR, as expected. After GR, DG maintained the lowest surface temperature due to a combination of high albedo and high heat flux into the subsurface.

为了节约用水，正在推动将灌溉草坪转换为“节水”景观设计。使用具有不同辐射和热特性的不同材料来完成此任务。我们进行了实地研究，测量了反射光谱的辐照度，反照率，能量平衡以及草（GR），人造草皮（AT），分解花岗岩（DG）和硬木覆盖（MU）的土壤和表面温度在由这些材料组成的景观中，地表温度受到控制。DG的反照率最高，大部分反射的太阳能在可见光波段。在我们测试的材料中，AT具有最低的反照率和最高的净辐射。DG是将能量传导到地下的最有效的材料，而MU则是最少的。AT和MU都将其大部分热能集中在地表，这表明将热能扩散到地下的能力很差。像预期的那样，潜热通量是GR能量平衡的主要组成部分。GR之后，由于高反照率和进入地下的高热通量的结合，DG保持了最低的表面温度。