The correct answer is option 1: landscaping related to save water. Xeriscaping is a concept that focuses on designing and maintaining a landscape that requires minimal water usage. It is particularly relevant in arid or drought-prone regions where water conservation is important. Xeriscaping aims to create a beautiful and functional outdoor space while reducing the need for irrigation.

Option 2, landscaping related to save soil erosion, is not directly related to xeriscaping. While xeriscaping practices can help prevent soil erosion by utilizing techniques such as mulching and proper plant arrangement, the primary goal of xeriscaping is to conserve water.

Option 3, weathering of rock surface, is completely unrelated to xeriscaping. Weathering of rock surface refers to the physical, chemical, and biological processes that cause rock to break down and change over time due to exposure to the elements.

Option 4, "All of the above," is not the correct answer as it includes option 3, which is unrelated to xeriscaping. Therefore, the correct answer is option 1: landscaping related to save water.