. Research methods in ecology. Plant ecology. 250 THE FORMATION phibious to mesophytic, and, in dry regions, xerophytic conditions. When the process of drying out occurs rapidly, as in a single summer, the original formation is destroyed, and the new vegetation consists largely of rudera! plants. A peculiar effect of climate occurs in regions with poor drainage, where the result of intense evaporation is to produce alkaline basins and salt lakes, in which the succession becomes more and more open, and is finally represented by a few stabilized halophytes, or disappears Fig. 63. A
. Research methods in ecology. Plant ecology. 250 THE FORMATION phibious to mesophytic, and, in dry regions, xerophytic conditions. When the process of drying out occurs rapidly, as in a single summer, the original formation is destroyed, and the new vegetation consists largely of rudera! plants. A peculiar effect of climate occurs in regions with poor drainage, where the result of intense evaporation is to produce alkaline basins and salt lakes, in which the succession becomes more and more open, and is finally represented by a few stabilized halophytes, or disappears Fig. 63. A typical gravel slide (talus) of the Rocky mountains, before invasion. 305. Succession by animal agency. Successions of this class are alto- gether of secondary importance, the instances in which animals produce de- nudation being relatively few. Such are the heaps of dirt thrown up by prairie dogs and other burrowing animals, upon which ruderal plants are first established, to be finally crowded out by the species of the original for- mation. Buffalo wallows furnish examples of similar successions in which the initial stages are subruderal, while overstocking and overgrazing fre- quently produce the same result with ruderal plants. 306. Succession by human agency. The activities of man in changing the surface of the earth arc so diverse that it is impossible to fit the resulting successions in a natural system. While man does not exactly make new soils, he exposes soils in various operations: mining, irrigation, railroad. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Clements, Frederic E. (Frederic Edward), 1874-1945. Lincoln, Neb. , University Pub. Co.
Size: 1758px × 1421px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectplantec, bookyear1905
