<span>It's is the second one. The waste materials generated by one organism are often reused by other organisms.Mass, or matter, is conserved in all physical and chemical changes. Matter is not created or destroyed within ecosystems, it only undergoes physical or chemical changes. One example of this process is that the waste materials generated by one organism are often reused by other organisms as food or nutrients.</span>
Lake Titicaca. It straddles the border of Bolivia and Peru, and sits right at the top of the Andes Mountains (in South America).
Into tropical savannas or steppes, in Africa, tropical wet climates transition into seasonally wet or dry tropical woodlands, followed by another transition.
The tropical savannas are identified by tall grasses and occasional trees. It can result from either climate, soil conditions, animal behavior, or agricultural practices, which limit the occurence of trees.