Study On The Change Of Landscape Pattern And Its Impact On Carbon Source And Carbon Sequestration In Kunming

As a result of the acceleration of industrialization,urbanization and anthropogenic effects,the regional landscape pattern has been changed and greenhouse gas emissions have been accelerated,resulting in unbalanced regional carbon balance,excessive greenhouse gases resulting in higher temperatures,resulting in disasters and damage to the living environment of organisms.With the support of remote sensing information technology and landscape ecology knowledge,the dynamic changes of regional landscape pattern and carbon source and sink in Kunming from 1995 to 2015 were analyzed in order to provide data support for low-carbon urban construction and scientific management planning in Kunming.The main results include:(1)The land use types in Kunming are divided into seven categories:woodland,cultivated land,shrubs and shrubs,garden land,water body,construction land and unused land.The results show that forest land and arable land accounted for 37%and 36%respectively in 1995 and 37%and 29%respectively in 2015,which indicates that the spatial pattern of Kunming is dominated by natural ecosystem.Compared with I1995,the area of woodland and arable land decreased slightly,the area of shrubs and shrubs increased,and the area of garden land,water body and construction land showed an increasing trend.Among them,the growth of construction land was obvious.The rapid development of urbanization in Kunming was the main reason for the rapid growth of construction land area.From the landscape pattern index,the heterogeneity and fragmentation degree of the overall spatial pattern of Kunming City increased,the dominance degree of natural ecosystem mainly composed of woodland,cultivated land,shrubs and shrubs increased,and the distribution of patches became more balanced.At the same time,the aggregation degree of the same types of patches increased.Among them,the dominance degree of woodland and shrubs and shrubs increased,patch aggregation degree increased and connectivity increased;the number of cultivated land patches decreased,patch aggregation degree increased;the number of garden patches increased,the aggregation degree increased;the fragmentation degree of water patches increased,the dispersion degree increased,the number of patches increased,and the connectivity decreased.(2)The total amount of carbon emissions in Kunming increased from 5.9242 million tons in 1995 to 53.0386 million tons in 2015,showing a sustained growth trend.Among them,energy consumption produces the largest carbon emissions,followed by industrial production process.In energy consumption,the carbon emission from raw coal and coke ranks first and second,and the carbon emission from raw coal is three times as much as that from coke.In industrial production,the carbon emission from cement and pig iron is in the first place,followed by carbon emission from steel.The total carbon sink of Kunming decreased from 51677,700 tons in 1995 to 504,026,000 tons in 2015.Although the carbon sink increased gradually after 2000 and increased at an average rate of 2%every five years due to the implementation of the policy of returning farmland to forestry,the carbon sink in 2015 has not returned to the level of carbon sink in 1995.Among them,forest carbon sequestration is the highest,followed by cultivated land carbon sequestration.Generally speaking,the distribution of carbon sinks in Kunming City increases gradually from south to North and from west to east.(3)Under the pressure of the rapid increase of population,energy consumption and carbon emissions,the carbon sink of Kunming remains basically unchanged,and the carbon intensity is gradually declining,which indicates that the construction of low-carbon cities in Kunming is more successful.However,in 2015,the net carbon emissions of Kunming City showed a negative value and exceeded the environmental carnying capacity by about 5%.The growth trend is not conducive to maintaining the stability of ecological carbon balance,which indicates that the measures for reducing carbon emissions in Kunming need to be further improved.