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

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Grasslands of the world
Physical improvements
The principal step in steppe improvement is to prevent deterioration by
inferior or harmful material and species. Dominance of superior constituents
cannot, in many instances, be achieved by grazing with a specific or varied
kind of livestock alone. Intentional elimination of less desirable species and
starika is needed to complement the action of grazing, cutting or even burning .
Oversowing (without adequate soil preparation) is rarely worth the effort
as seedlings have great difficulty in establishing themselves in an established
sward, however sparse, except perhaps in genuinely humid environments.
Some effective measures are: 1. removal of tussocks, shrubs and starika;
2. removal of litter and brushwood after floods; 3. regulation of silt deposition
on floodplain meadows; and 4. regulation of the water regime (drainage of
stagnant surface waters; liman irrigation; temporary flooding of floodplain
meadows; construction of ice dykes; protection for snow retention).
A lot of the clearing can be done with appropriate machinery and the same
applies to the levelling that is needed to enable a field to be mown for hay . The
removal of major deficiencies in moisture and fertility conditions contributes
to the prevalence of more desirable grasses and or clovers; the same applies to
regimes of alternate grazing and mowing on the one hand and of early and late
mowing on the other. By assisting the correct distribution of spring waters,
natural limans can be improved without great effort. Solonchaks and boggy
places should not receive water.
Snow retention through windbreaks and standing vegetation is another
effective measure in the forest steppe , steppe and semi -desert zones . Crop
yields are greatly increased. In experiments by N.G. Andreev in the 1930s in
Saratov Oblast, yields of Agropyron racemosum on fallow land were raised by
50–75 percent (see also Andreev, 1974a,b). Elsewhere, Stipa -Festuca sulcata
pastures increased by 16–31 percent in yield (Larin, 1956). Snow retention
can be combined with arrangement of ridges and furrows to block the flow of
water from melting snow.
EXAMPLES OF THE EFFECT OF MANAGEMENT ON BOTANICAL
COMPOSITION
Stipa capillata , common on virgin steppe and old fallow in the Rostov,
Volgograd and Stavropol areas, is troublesome since the seed has awns which,
when caught in the wool not only spoil it, but bore through the skin and
when in greater numbers can cause death of goats and sheep . Burning has
proved useless. Grazing with larger herbivores is recommended. Light grazing ,
especially when early, and early mowing increases rather than decreases this
grass . Pastures should not be grazed earlier than the heading phase of Festuca
sulcata and Stipa lessingiana . These grasses will then remain almost uneaten
and will go to seed, while the later heading Stipa capillata will be eaten out
selectively. Mowing of Stipa spp. must be conducted systematically from early