Reasons:

* Albedo: Albedo is the measure of how much sunlight a surface reflects. Sand has a higher albedo than tree land.

* Surface Color: Sand is typically light-colored (white, yellow, or beige), while tree land is dark green. Light colors reflect more sunlight than dark colors.

* Surface Texture: Sand has a smooth, granular surface, which allows for more efficient reflection of sunlight. Tree leaves, on the other hand, have a rough, irregular surface that absorbs more sunlight.

* Vegetation Cover: Tree land has dense vegetation that intercepts sunlight and reduces reflection. Sand, being a bare surface, has no vegetation cover to absorb sunlight.

In Summary:

Sand's light color, smooth texture, and lack of vegetation cover result in a higher albedo and therefore reflect more sunlight than tree land.