There are three main heat transfer mechanisms: conductive, convective, and radiative.
Conductive transfer means direct transfer from one item to another it's in contact with. The transfer rate depends on the empirically determined thermal conductivity of both materials.
Convective refers to heat transfer between an object and a moving fluid such as wind. This depends heavily on the total surface area available (such as fins on a radiator).
Radiative means absorption or emission of photons. The energy transfer rate depends on the surface properties, called "emissivity" or equivalently "absorptivity" and is wavelength-dependent for any given material.
OK, so with that in mind, yes a black object generally will absorb more sunlight than a lighter shade of ground/dirt. This is a generality, as the absorptivity in the infrared may be different than in the visible. At the same time, the conductive heat loss/gain to the ground depends on the total contact area, and further will be much greater if the ground is damp, because water is good at conducting a lot of heat 'fast.' After dark, the radiative processes are sort of reversed. It's not an exact reversal because the spectral radiation rates depend on the material AND on the temperature of the object. (actually the radiation rates apply all the time; it's just that in daylight each object absorbs more light than it radiates until it reaches a thermal equilibrium).
In sum, the black object probably will get cold faster, and get colder than the ground. As a practical example, come to New England in the late Fall. On cool nights, black stuff such as roof shingles often frost over when other things like white walls don't, because of radiative cooling.
