The Danube Delta, the second largest river delta in Europe, is the center of global biodiversity. The Danube Delta plays an important role in the self-purification of the Danube water and the binding of pollutants. But over the past 100 years, human intervention has begun in natural processes in the estuary of the Danube, a change in the hydrography of the delta. To ensure the protection of natural complexes of the Danube region, in accordance with the Decree of the President of Ukraine in 1998. The Danube Biosphere Reserve, subordinate to the National Academy of Sciences of Ukraine, was created on the basis of the Danube Plavni Nature Reserve. By the decision of the International Coordinating Committee of the UNESCO Program “Man and the Biosphere” in 1999 The Danube Biosphere Reserve is included in the global network of biosphere reserves as part of the bilateral Romanian-Ukrainian biosphere reserve “Danube Delta”. According to Article 18 of the Law of Ukraine “On the Nature Reserve Fund of Ukraine” (1992), the legal regime of protected areas of biosphere reserves provides for the limited use of this territory, in particular the prohibition of the construction of structures, roads, linear and other transport and communication facilities not related to the activity of the reserve, as well as the passage and passage of unauthorized persons, the movement of mechanical vehicles.
A promising approach in obtaining relevant information for monitoring hydrographic conditions and other environmental components on the territory of the Danube Delta is the use of remote sensing methods of the Earth (ERS). First of all, this is a thematic analysis of images in various spectral ranges obtained by an onboard special complex of remote sensing spacecraft. With their help, you can track changes in the water area of water bodies. After analyzing the results of satellite imagery research for 1987 and 2017, we can conclude that in a fairly short period of time (30 years), significant changes occurred on the territory of the Danube Delta: 1) old lake formed in almost every channel, or the river changed its way; 2) also tangible economic activity of a person – the outlines of the shores have changed, drainage reclamation has been carried out in some wetlands and they have been converted into farmland; 3) part of the territory is untouched – probably refers to the reserve fund. The coastline has changed, which can be explained by the creation of fish farms there, or the flooding of land, since they coincide spectrally with the water surface.
As for the technique of working with satellite images, it is better to use the NIR (near infrared) channel, which is in the wavelength range from 0.76 to 0.9 μm with a discontinuity of 30 meters, to determine objects.
Land use analysis of coastal belt in the coastal area of Langkat Regency North Sumatra Province using Sentinel 2 Satellite imagery
