定義： A savanna biome is a woodland biome which has seasonal water availability and includes, across its entire spatial extent, trees spaced sufficiently far apart to allow an unbroken layer of grass, sedge (Cyperaceae) or rush (Juncaceae) communities to live.
定義： A forest biome is a terrestrial biome which includes, across its entire spatial extent, densely packed vegetation which strongly limits light penetration to the forest floor.
定義： forests which are inundated with freshwater, either permanently or seasonally. They normally occur along the lower reaches of rivers and around freshwater lakes
定義： A wetland that features permanent inundation of large areas of land by shallow bodies of water, generally with a substantial number of hummocks, or dry-land protrusions.
定義： A flat expanse of ground covered with salt and other minerals, usually shining white under the sun. A salt pan is formed where water pools. A saline pan would be a lake or a pond if it were located in a climate where the rate of water evaporation were not faster than the rate of water precipitation, i.e., if it were not in a desert. If the water is unable to drain into the ground, it remains on the surface until it evaporates, leaving behind whatever minerals were dissolved. Over thousands of years, the minerals (usually salts) accumulate on the surface.
