ECOLOGICAL FOOTPRINT DYNAMIC MODELLING AND MEASUREMENT OF LOESS PLATEAU VALLEY BASED ON ARIMA MODEL:A CASE STUDY ON LANZHOU CITY
To explore the causes of eco-footprint dynamic changes from perspective of economic development,this paper measures the developing path of the per capita ecological footprint from 2002 to 2014 in Lanzhou,a loess plateau valley city,uses ARIMA model to forecast its ecological footprint changing trend from 2015 to 2020.The per capita ecological footprint is rising from 2.70 hm2 in 2002 to 4.25 hm2 in 2014,increase of 1.57 times.And the rising rate of the per capita ecological footprint reaches to 4.04%,7.84%lower than its GDP's growing rate 11.88%,suggesting Lanzhou's economic development speed is higher than speed of resources and environmental consumption.The per capita ecological footprint of Lanzhou from 2015 to 2020 still shows a rising trend,forecasted to reach up to 4.48 hm2,4.61 hm2,4.75 hm2,4.89 hm2,5.02 hm2 and 5.17 hm2,with an enlarging ecological deficit.Lanzhou's gross ecological footprint is 19.59 times of the total area of urban land use,indicating a strong correlation between economic growth and ecological demands,indicating the inflection point of Environmental Kuznets curve doesn't take place,implying a unsustainable status.This paper presents a path to decreasing Lanzhou's ecological footprint from adjusting industrial structure,decreasing ecological deficit to promote economic quality and sustainable capacity,advancing green development,and constructing an ecological network of ecological diversity,appropriate layout,full-functional integration of natural ecosystems and rural-urban union to increase eco-environmental capacity.