What is chalk steppe?
The name ‘chalk steppe‘ is convenient because of brevity but not exactly correct. Plant communities of chalk outcrops in hilly terrain are very diverse. Some are true steppe with dominance of graminoids and partly sedges, others are communities in which perennial herbs prevail especially cushion dwarf semishrub plants. Here some bushes and forest patches may be found as well. The appearance of chalk steppe of Eastern European plains is closest to mountain steppe of arid regions.
The species composition of such communities is unique and sharply differs from surrounding matrix. The ranges of chalk plants are often enclaves well distant from main areas of distribution of same or similar species which lay far to the south or east in Western Asia, Caucasus or Altai.
Chalk is very prone to washing thus main factor in distribution pattern of different plant communities is water erosion. The intensity of water flow is quite distinct in different parts of any chalk hill, so the processes of washing of bedrock, transfer and accumulation of chernozem soil and chalk particles are very distinct as well. This results in variegated vegetation cover and in sharp changes of vegetation pattern on small areas. Such diversity reflects in the composition of animal communities. Animals who live on chalk are also sensitive to overall sparseness of vegetation cover e.g. to the presence of patches of bare chalk and to weak development of plant debris.