Spatiotemporal evolution and prediction of habitat quality in Hohhot City of China based on the InVEST and CA-Markov models

With the acceleration of urbanization,changes in the urban ecological environment and landscape pattern have led to a series of prominent ecological environmental problems.In order to better coordinate the balanced relationship between city and ecological environment,we selected land use change data to evaluate the habitat quality in Hohhot City of China,which is of great practical significance for regional urban and economic development.Thus,the integrated valuation of ecosystem services and tradeoffs(InVEST)and Cellular Automata-Markov(CA-Markov)models were used to analyze,predict,and explore the Spatiotemporal evolution path and characteristics of urban land use,and forecast the typical evolution pattern of land use in 2030.The results showed that the land use types in Hohhot City changed significantly from 2000 to 2020,and the biggest change took place in cultivated land,grassland,shrub,and artificial surface.The decrease of cultivated land area and the increase of artificial surface area were the main impact trend of land use change.The average value of habitat quality had been decreasing continuously from 2000 to 2020,and the values of habitat degradation were 0.2605,0.2494,and 0.2934 in 2000,2010,and 2020,respectively,showing a decreasing trend.The decrease of habitat quality was caused by the needs of economic development and urban construction,as well as the impact of land occupation.During this evolution,many cultivated land and urban grassland had been converted into construction land.The simulated land use changes in 2030 are basically the same as those during 2000-2020,and the habitat quality will still be declining.The regional changes are influenced by the urban rapid development and industrial layout.These results can provide decision-making reference for regional urban planning and management as well as habitat quality evaluation.

Atmospheric Pollution Control Effect of Key Cities in Inner Mongolia in 2014

APEC conference was held in Beijing during November 3- 12,2014. Hohhot City and Baotou City fall into the peripheral key air pollution control cities in the ＂ Beijing- Tianjin- Hebei＂ region. Inner Mongolia government adopted powerful pollution control measures in the period of the conference. According to pollutant concentration data and meteorological data etc. in the course of the event and the same period of last year,the atmospheric pollution variations and control effect were discussed in this study. The results showed that during October 1- 25,2014,there were 16 days with air pollution in Hohhot City and 15 days with air pollution in Baotou City,respectively increasing by 8% and 34% compared with the same period of 2013,and the concentration of particulate matter was also higher than that of last year. During October 22- 24,2014,Hohhot and Baotou cities were polluted persistently. The variation features of hourly concentration of main pollutants PM（10） and PM2. 5were similar to those in the same period of 2013. That is,the pollutant concentration reached the maximum from 21：00 to 23：00,and the minimum appeared from 15： 00 to 19： 00 in the next day. In the course of the event,the concentration of particulate matter in the two cities stared to reduce greatly on October 26. From October 26 to November 13,there were no days with air pollution in Hohhot City,decreasing by 100% compared with the same period of 2013; there were five days with air pollution in Baotou City,and the numbers of days with slight,moderate and severe pollution reduced by 37%,100% and67% respectively compared with the same period of last year. The persistent air pollution from October 22 to the first 10 days of November was related to unfavorable meteorological conditions,and the meteorological condition in the same period of 2014 was even worse. In the course of the event,the Inner Mongolia Government adopted air pollution control measures around October 25 and began to adopt some powerful pollution control measures on November 1. As a result,air pollution in key cities has been controlled effectively. This event showed that urban atmospheric pollution problem can be resolved,and we should take an optimistic attitude towards this matter.