Evaluation of Ecological Environment Quality of Typical Forest Parks

Forest tourist areas have an excellent ecological environment,which is conducive to people's physical and mental health.In this study,Fuzhou National Forest Park and Wuying National Forest Park were selected as typical representatives of the southern and northern forest parks,respectively,which were compared by qualitative and quantitative research methods from such five aspects as air quality,climate quality,water environment quality,acoustic environment quality and biological population in some forest areas.The results showed that Fuzhou National Forest Park has a concentration of negative oxygen ions much higher than Wuying National Forest Park,and is thus more conducive to people's health;and it has the characteristics of warm and comfortable climate throughout the year and high biodiversity,but the noise is 4.35 db higher than Wuying National Forest Park,and the water quality is slightly poorer than that of Wuying National Forest Park.And its DO value is about 3.89 smaller in autumn than in summer.In Wuying National Forest Park,the concentration of negative oxygen ions is 53.6% lower than Fuzhou National Forest Park,but it is also above the national standard.The climate is only comfortable in June-August,and is colder or cooler in other months.The water quality is better than that of Fuzhou National Forest Park.In particular,the PH value is about 0.38 lower than that of Fuzhou National Forest Park.It has its own unique biological characteristics.The number of tourists in summer is higher,resulting in higher noise in summer than in autumn.The two forest parks in the north and the south are both good places for people to relax and enjoy.

Climate background of the evolution from Paleolithic to Neolithic cultural transition during the last deglaciation in the middle reaches of the Yellow River

Shizitan in Jixian County, Shanxi Province, is a site of transitional period from Paleolithic to Neolithic. The dating and the sporopollen analysis show that the middle reaches of the Yellow River where the site is located had been maintaining a steppe environment during 35.1-9.4 kaBP, in which, 35.1-17 kaBP belonged to the last glacial. With cold and dry climate, this period featured a desert steppe environment. In the late of this period, the area had a cold and half-humid steppe environment. The 17.0-11.9 kaBP belonged to the early- and mid-period of the last deglaciation. Mild and half-arid steppe alternates with mild and half-arid steppe, with a small amount of deciduous broadleaf species. During the period of 11.9-10.5 kaBP, cold and dry glacial climate appeared once more, featuring a desert steppe environment. During 10.5-9.4 kaBP, it is mild and half-arid, and later transited toward warm and half-humid. The early phase of this period featured a steppe environment and the later transited into a