Communities of hydrobionts developing at the water-rock interface in Lake Baikal

Development of benthic communities on rocks from the interdisciplinary test site near Cape Berezovyi (southern Baikal) is analyzed. Rock plates were placed on the bottom in the shallow-water zone of Baikal for six months, and a community consisting of microorganisms, microphytobenthos, and meiobenthos developed on them. The development and activity of hydrobionts depended on the chemical composition and structure of the rock. Marble and granite plates were populated by them more selectively than amphibolite plates. It is supposed that the biota plays an important role in destruction of rocks in the shallow-water zone of Baikal.     

Investigation of the aerosol structure over an urban area using a polarization lidar

The paper presents a lidar study of the aerosol structure in the planetary boundary layer in the case of radiation fog and haze. A conceptual model of the dynamics of the depolarization coefficient profile during the mixing layer development, taking into account the presence of a multilayered inversions and radiation fogs, is proposed. Various techniques are employed in the processing of the lidar signal in order to determine the mixing layer height as well as more details of the aerosol structure in the low atmosphere, namely, finding the maximum of the signal returned from the lowest temperature inversion, the crossing point of the S function's first derivative with the x axis, and profiles of the depolarization ratio. After the complete destruction of the stable stratification, a low constant value of the depolarization ratio within the newly formed mixing layer is being observed. The study of stable boundary layer disintegration and convective boundary layer formation in the presence of fogs and/or clouds is of both scientific and practical significance in what concerns the protection of the environment and the aviation meteorology.