Assessment of the State of Trifolium Repens L. Cenopopulations in Arid Conditions in the Surkhandrarya Region (Uzbekistan)

The morphological variability and plasticity of traits, age structure, abundance, and density of Trifolium repens L. were studied in arid conditions of the Surkhandarya region of the Republic of Uzbekistan. These studies were conducted on different phytocenoses under anthropogenic load. The species is characterized by low–medium plasticity and medium variability of the morphological traits. In undisturbed cenopopulations, high vitality (IVC = 0.87) and a large proportion of pregenerative individuals are observed. Increased anthropogenic impact leads to a decrease in vitality (IVC = 0.62). An ontogenetic structure with the left-sided (CP 1) and centered type (CP 2, 3, 4) is observed. The characteristic ontogenetic spectrum of Trifolium repens is left-sided, with an absolute maximum in one of the pregenerative groups. Cenopopulation 1 coincides with the characteristic type of the species studied; it has no anthropogenic load and a high projective cover (90%), and the density of individuals is 5.3 ind./m2. Cenopopulations 2–4 do not coincide with the characteristic one. Their young fractions die off, and middle-aged individuals accumulate. The reasons for the reduction in the number of individuals are the negative impact of the anthropogenic factor and climate change.