Gardens and crop fields are examples of .......... ecosystem.
Humans are the dominant species in the biosphere. They modified the ecosystems to suit the social and economic needs. They even created new ecosystems. These man-made, or artificial ecosystems are terrestrial as well as aquatic. The terrestrial ones include rural and urban settlements, plantations, orchards, gardens, parks, croplands and animal farms. The man-made aquatic ecosystems include dams, reservoirs, lakes, canals, fishery tanks, ponds and aquaria.
So, the correct answer is 'artificial or man-made'.