四川柑橘生产空间的时空演化及驱动机制研究

SPATIAL AND TEMPORAL EVOLUTION AND DRIVING MECHANISM OF CITRUS PRODUCTION AREA IN SICHUAN

关键词:  农业土地系统  时空过程  空间面板模型  驱动机制  柑橘

Key words:  agricultural land system  spatiotemporal process  space panel model  driving mechanism  citrus

摘要:

目的 农作物空间演化的本质是农业土地利用变化的具象反映，揭示农作物空间的时空过程，明晰其与自然、社会和经济等因素的定量响应关系，有助于解释农业土地系统变化过程与机制。柑橘空间是我国南方地区重要的农业土地利用类型，其空间变化对优化农业土地系统具有重要影响。方法 针对已有研究在空间尺度、响应机制的局限，文章在分析柑橘空间时空过程的基础上，采用空间杜宾模型对解释变量的空间溢出效应及其作用机制进行了实证分析。结果 1980—2015年四川柑橘空间快速扩张，经历了快速扩张期（1980—1995年），强烈震荡期（1995—2005年），扩张恢复期（2005—2015年）。柑橘空间表现出高度集聚，在地理上呈现出空间相关性。川中丘陵区是柑橘空间变化最为强烈的区域。结论 四川柑橘空间的时空过程受多种驱动因素共同作用，表现出明显的“自然—人文”驱动特征。与海拔、降水量、最热月平均气温、年日照时数、气温年较差、城镇化水平、消费水平和技术进步8个解释变量呈负相关，上述变量每增加1％，柑橘空间收缩0.61％、0.358％、0.844％、1.784％、4.734％、0.398％、2.473％和0.181％。与坡度、无霜期、劳动力投入强度、有效灌溉面积、农药投入强度、路网密度和经济反哺能力7个解释变量呈正相关，上述变量每增加1％，柑橘空间扩张1.270％、1.044％、0.542％、0.172％、0.285％、0.626％和0.356％。

Abstract:

The essence of crop spatial evolution is the concrete reflection of agricultural land use change. Revealing the temporal and spatial process of crop space and clarifying its quantitative response relationship with natural, social and economic factors are helpful to explain the change process and mechanism of agricultural land system. Citrus space is an important type of agricultural land use in southern China, and its spatial change has an important impact on the optimization of agricultural land system. In view of the limitations of existing studies in spatial scale and response mechanism, based on the analysis of citrus spatial and temporal process, this paper used a spatial Dobbin model to empirically analyze the spatial spillover effect of explanatory variables and its mechanism. The results showed that: from 1980 to 2015, Sichuan citrus space expanded rapidly, including experienced rapid expansion period (1980-1995), strong shock period (1995-2005) and expansion recovery period (2005-2015). Citrus space showed a high degree of agglomeration and spatial correlation in geography. The hilly region of the Central Sichuan Basin was the area with the strongest spatial change of citrus. The conclusions are listed as follows. The spatiotemporal process of citrus space in Sichuan is affected by many driving factors, showing obvious "nature-humanity" driving characteristics. It is negatively correlated with eight explanatory variables: elevation, annual precipitation, average temperature in July, annual sunshine hours, annual temperature range, urbanization level, consumption level and technological progress. Every 1% increase of the above variables, the spatial contraction of citrus is 0.61%, 0.358%, 0.844%, 1.784%, 4.734%, 0.398%, 2.473% and 0.181%. It is positively correlated with seven explanatory variables: slope, frost free period, labor input intensity, effective irrigation area, pesticide input intensity, road network density and economic support capacity. Every 1% increase of the above variables, the spatial expansion of citrus is 1.270%, 1.044%, 0.542%, 0.172%, 0.285%, 0.626% and 0.356%.