In the paper, the simulation PROP5 program is used to predict the sound level in proximity of a road with defined surroundings. The simulation involves road geometry (number of lanes and their positions) and traffic structure (vehicle flow rates and their average speeds), with equivalent omnidirectional point sources representing vehicles. In Part I of the paper, the agreement between measurement and simulation results is tested to verify the accuracy degree of the applied models of a road, as a noise source and propagation throughout surrounding space. In Part II, using the pre-tested simulation program, the possibility of acoustic climate improvement has been analyzed.

In order to simulate the warming effects on Arctic wetlands, three passive open−top chambers (OTCs) and three control cage−like structures (CCSs) equipped with soil temperature and soil volumetric water content (VWC) probes for continuous micro− climatic measurements were installed in a wet hummock meadow, Petuniabukta, Billefjorden, central Spitsbergen, in 2009. The warming effects on primary productivity were investigated during summer seasons 2009 and 2010 in cyanobacterial colonies of Nostoc commune s.l., which plays an important role in the local carbon and nitrogen cycles. The microclimatic data indicated that the effect of OTCs was dependent on microtopography. During winter, two short−term snow−thaw episodes occurred, so that liquid water was available for the Nostoc communities. Because of the warming, the OTC hummock bases remained unfrozen three weeks longer in comparison to the CCSs and, in spring, the OTC hummock tops and bases exceeded 0 ° C several days earlier than CCS ones. Mean summer temperature differences were 1.6 ° C in OTC and CCS hummock tops, and 0.3 ° Cinthe OTC and CCS hummock bases. The hummock tops were drier than their bases; however the VWC difference between the OTCs and CCSs was small. Due to the only minor differences in the microclimate of OTC and CCS hummock bases, where the Nostoc colonies were located, no differences in ecophysiological characteristics of Nostoc colonies expressed as photochemistry parameters and nitrogenase activities were detected after two years exposition. Long−term monitoring of Nostoc ecophysiology in a manipulated environment is necessary for understanding their development under climate warming.