Uzbekistan: Rehabilitation of Desert Rangelands Affected by Salinity, to Improve Food Security, Combat Desertification and Maintain the Natural Resource Base - Combating Desertification in Asia, Africa and the Middle East - page 241

works. Such a multidisciplinary approach of vegetation assessment was applied
in semi desert vegetation of Karnabchul (see Fig. 13.3 ) where grazing induced
rangeland degradation is common as observed in other desert areas of Uzbekistan
(Rajabov 2010 ).
The effect of grazing is often localized and is ubiquitous around watering points
and settlements in Uzbekistan. The grazing pressure diminishes with distance from
these foci and forms a gradual change in vegetative cover, species composition
and soil properties. To study such systematic changes, grazing gradient method has
been widely used to examine the plant responses to grazing in different ecological
zones (e.g. Austin 1977 ; Andrew 1988 ;Lietal. 2008 ). Grazing gradient analysis
provides the ideal method by which to detect plant traits to a certain range of grazing
pressures (Andrew 1988 ).
Interdisciplinary research based on an ecological approach was applied to detect
the fine scale degradation processes and to understand full scenarios of plant-
soil-animal interactions in order to keep the rangeland ecosystems in balance.
This approach is the focus of this chapter and is illustrated by our field work in
Uzbekistan.

2 Description of the Study Sites

The studies on desert vegetation along a salinity gradient were conducted in
Kanimekh district at the Research Station of the Uzbek Research Institute of
Karakul Sheep Breeding and Desert Ecology (lat. 41 ı N and Long 60 ı Eatan
altitude of 113 m). This region has a typical inland arid climate with a hot, dry
summers and cold winters: annual mean temperature is 11.4 ı C, and annual mean
precipitation is 120 mm, which falls in the growing season from May to September.
We have chosen Kyzylkesek site - an area located between two hot springs
(vertical drainage flow) in Central Kyzylkum Desert in order to determine spatial
changes of vegetation as from the xerophytes in sandy dunes towards typical
halophytes in Karakata salt depression (Fig. 13.2 ). Each zone differs by its relief,
total soluble salts, floristic composition and botanic diversity.
Additionally we have conducted field research to assess the spatial and temporal
vegetation succession of Karnabchul (a typical sagebrush-annuals semidesert range-
land) as a function of piospheric effects in two different range sites (39 ı 50 0 Nand
65 ı 55 0 E)showninFig. 13.3 .

2.1 Methodology

2.1.1 Vegetation Surveys

Geobotanical descriptions were done using 2 m 50 m transect (in semi shrub plant

communities) and 5 m 50 m transect (in shrub plant communities - Haloxylon