Abandonment. If a nonconforming use of a building ceases and is abandoned for a continuous period of one year or more, subsequent use of such building shall be in conformity with the provisions of this chapter. If a nonconforming use of land ceases or is abandoned for any length of time for any reason, subsequent use of such land shall be in conformity with the provisions of this chapter. For the purpose of this chapter, abandonment shall commence when reasonable efforts to reestablish (such as lease, rental, sale, etc.) a nonconforming use have ceased.