A Study On The Coupling And Coordination Relationship Between Landscape Ecological Security And Multi-function Of Cultivated Land In Mountainous Areas Of Southwest China ——Taking Karst Valley Area As An Example

Cultivated land is the core element to ensure national food security,realize rural revitalization and promote the construction of ecological civilization.With the high-quality social and economic development,human demand for cultivated land is no longer limited to a single function of food supply,and the demand for derivative functions such as cultivated land livelihood security,landscape aesthetics,and leisure tourism has gradually become prominent.At the same time,pursuing the benign development of regional economic benefits and ignoring the changes in the landscape pattern of cultivated land will lead to aggravation of the phenomenon of non-agriculturalization of cultivated land and the deterioration of ecological security.Therefore,how to meet the diverse needs of human beings while protecting the ecological environment and realize the sustainable utilization of cultivated land has become a huge challenge,and the construction of landscape ecological security pattern and the multi-functional play of cultivated land are to solve such contradictions.inevitable choice.At present,there are many unilateral studies on the relationship between farmland ecological security and multi-functionality in academia,but the research on the relationship between farmland landscape ecological security and multi-functionality is not perfect,and the relationship between the two has not received enough attention.Based on this,based on land use data,this paper carries out the evaluation of the ecological security and multi-functionality of cultivated land landscape,and reveals the evolution characteristics of the trade-off and synergistic relationship between the ecological security of cultivated land and various functions of cultivated land from multiple scales.Geographical detector,to explore the 20-year20-year arable land landscape ecological security and multi-functional coupling coordination relationship in the karst trough valley area,and select 2020 as the time node to explore the main factors of multi-functional and coupling coordination of cultivated land for four landform types in the karst trough valley area.influencing factors.The main findings show that:(1)From a spatial point of view,the low-value areas of arable land landscape ecological security are mainly distributed in the northern and central-eastern valley areas,while the high-value areas are mainly distributed in the southwest.On the grid scale,the ecological security of cultivated land landscape in areas with strong human activities is relatively low,and it is concentrated in the low-value areas and has a tendency to gradually expand outward.The landscape ecological security of cultivated land is as follows: partitioned trough area > complex anticline trough area > partitioned trough type trough area > tightly folded trough area;on the administrative district scale,the low level of arable land landscape ecological security in 2000 It is mainly distributed in 12 counties(cities,districts)in the northeast,accounting for about8.82% of the total,while the high level is mainly distributed in the southwest,accounting for about 3.68% of the total.From 2000 to 2020,the change rate of cultivated land landscape ecological security was mostly between-5% and-2%,and the value was small and showed a decreasing trend;under the seven types of cultivated land combination types,the distribution of cultivated land landscape ecological security of various combinations was different.Significantly,the landscape ecological security of each grade of cultivated land is most distributed under the combination of "arable land + natural habitat",and the distribution of high and low values of landscape ecological security of cultivated land under the combination of "arable land + artificial surface" is quite different,showing "more high values,less low values".quantitative characteristics.(2)Grain production and soil conservation are on the rise,with grain production increasing rapidly,habitat quality,habitat connection,population bearing and landscape aesthetics showing a decreasing trend.Population bearing declines rapidly,while natural and habitat connections change steadily.(except for the partitioned trough area);the synergy between food supply and population carrying is strong,the trade-off between habitat quality and habitat connection is strong,and the trade-off synergy of each function has a significant scale effect.The degree of synergy among the various functions of cultivated land is constantly weakening and the degree of trade-off is increasing,but the synergistic trade-off relationship of each function remains unchanged.(3)From 2000 to 2020,the multi-functionality of cultivated land in the karst trough valley area has a gradual upward trend,and the stability of spatial distribution is relatively high.The closely folded trough area and the partitioned trough area have similar multi-functional and quantitative structural characteristics of each grade,and the overall performance is: closely folded trough area > partitioned trough area >partitioned trough area > double back Inclined trough area.On the administrative district scale,from 2000 to 2020,the multi-functional arable land was dominated by the middle grade.In 2000,the multi-functional arable land was mainly distributed in Banan District,Zengdu District,Chengkou County,Cili County,and Hepingli County.68counties(cities,districts),accounting for 50.37% of the total.(4)Based on the coupling coordination degree model,the coupling coordination degree and the evolution type of the coupling coordination degree between 2000 and 2020 of the farmland landscape ecological security and multi-function in the karst valley area were calculated.From the grid scale,the coupling coordination degree is low in the north and southeast,and high in the middle.There is an obvious phenomenon of simultaneous expansion of high-value areas and low-value areas.Spatially,there is a significant positive correlation between the ecological security of cultivated land landscape and multi-functionality,indicating that improving the landscape ecological security pattern of cultivated land to a certain extent can improve the multi-functionality of cultivated land.The time change of the coupling coordination degree of the two shows a significant decreasing trend,among which the gap-type trough area and the complex anticline-type trough area have a greater decline.The evolution type of coupling coordination degree shows the spatial distribution characteristics of “less ecological security lag” and “multi-functional lag”.Among the four trough landform types,the farmland coupling and coordinated development type in the tightly folded trough area is dominated by low degree of coupling coordination-low and low synchronization;The partition-type trough area is dominated by good coupling coordination-multi-function lag;the complex anticline-type trough area is dominated by basic incoordination-multi-function hysteresis.(5)There are significant differences in the main controlling factors of the spatial distribution of multi-function and coupling coordination degree of cultivated land in different types of karst trough valleys,but the GDP and average annual rainfall are still the main influencing factors.The interaction between GDP and average annual rainfall has a high impact,and the explanatory power is between 39% and 66%.In general,the explanatory power of the interaction of each factor of the coupling coordination degree in the four landform types is less than Multifunctional arable land.