Grasslands of the World.pdf - Disasters and Conflicts - UNEP

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Plate 10.3
Festuca sulcata
Grasslands of the world
• To about the fifteenth year: Stipa lessingiana becomes predominant (return to
the initial virgin steppe).
Thus, at least five distinct associations are found. Depending on the management
of the fallow and on the previous cropping history of the land, several
tens of associations may be distinguished. Although each modification has significance
for current utilization, habitat potential remains very much the same.
Shennikov, therefore, preferred to allocate Ramenskii’s virgin low-sward grass
stage to “herbaceous steppe”; the Agropyron fallow to “(mesophilic) meadow
type ” and the Polygonum association to “herbaceous annual vegetation ”, all
forming part of the Herbosa basic type of vegetation (see below). Shennikov’s
was a commendable effort of amalgamating the elements that unite rather than
divide.
The emphasis at the time on terminology such as “phytocoenosis ” and
“zoocoenosis ”, together forming the biocoenosis and interrelating with the
biogeocoenosis , is worth noting (Sukachev, 1945). Another emphasis was the
division into four vegetation types : 1. Lignosa – tree-shrub; 2. Herbosa – herbaceous
plants (see above); 3. Deserta – desert plants; and 4. Errantia – various.
Shennikov’s hierarchy for a particular situation might be: 1. Vegetation -type
group : Herbosa. 2. Type of vegetation : meadow (humid-grassland mainly used
for hay ). 3. Class of formations: true meadow (as against steppe or swamp).
4. Formation group: coarse grass , coarse sedge. 5. Formation: Alopecurus