The Project is aimed at the study the environments of the Lena River Delta, New Siberian Islands as well as the adjacent southeastern Laptev Sea shelf in time and space in order to better understand the Arctic's response to global change. To meet this goal successfully the following objectives have been set: (i) to study modern terrestrial and aquatic biocoenoses from the Lena River Delta, the New Siberian Islands, and the adjacent southeastern Laptev Sea shelf within the concept of present-day Arctic conditions; (ii) to implement high-resolution reconstructions of paleoenvironments for the entire southeastern Laptev Sea shelf region and its adjacent land areas since late Pleistocene and into most recent times as background understanding for environmental change due to anthropogenic influence. To attain the formulated objectives, the following steps will be undertaken: - Analysis of high-latitude Arctic biota within the southeastern Laptev Sea, New Siberian Islands and Lena Delta area in relation to modern environments; population structure and dynamics; production estimations; establishment of major peculiarities of thanatocoenoses formation; - Elaboration of the Late Pleistocene - Holocene stratigraphical scheme for the Laptev Sea shelf, New Siberian Islands and the adjacent hinterland as a basis for paleoenvironmental reconstructions; - Investigation of present-day and past variability in the Lena River discharge as one of the major environmental factors in the development of marine and coastal biocoenoses and indicators of climate changes; - Reconstruction of the Holocene coastal peat development of the Lena Delta and New Siberian Island areas over various time scales; - Reconstruction of the paleoenvironmental history and land-sea interactions within the Lena Delta and New Siberian Islands during the Late Pleistocene and Holocene as a basis for the possible scenarios of future development. The obtained results will contribute much to the understanding of the present-day functioning of the highly sensitive marine and terrestrial ecosystems and would be recommended for the Ecological Program of Sakha Republic.