河西走廊县域人均粮食占有量的时空演变与驱动力分析

SPATIO-TEMPORAL EVOLVEMENT AND ITS DRIVING FACTORS OF PER CAPITAGRAIN POSSESSION AT COUNTY LEVEL IN HEXI CORRIDOR

关键词:  人均粮食占有量 时空演变 GWR 驱动力 河西走廊

Key words:  per capita grain possession  spatial-temporal evolvement  GWR  driving factors  Hexi Corridor

摘要:

粮食安全始终是关系我国国民经济发展、社会稳定和国家自立的全局性重大战略问题。我国政府明确提出“以我为主、立足国内、确保产能、适度进口、科技支撑”的粮食安全新战略，并将其作为首要工作任务。文章以河西走廊20个县域为研究单元，运用ESDA和GWR模型，分析河西走廊人均粮食占有量的时空格局演变及变化的驱动力。结果表明：1990~2014年，河西走廊人均粮食占有量呈波动增长-急剧减少-持续增长变化特征；县域人均粮食占有量增长类型以总产低、快速增长型为主，中东部的张掖全市、永昌县、凉州区等地粮食生产作用日益明显；人均粮食占有量总体空间关联度在提高，高高聚集和低低聚集态势增强；人均粮食占有量变化的驱动因素中，种植结构＞复种指数＞人均耕地面积＞单位面积产量＞非农就业机会＞人均GDP，驱动因素表现出过渡性、空间分异特征，单位面积产量、非农就业机会和人均GDP的变化对人均粮食占有量的影响具有空间分异特征；种植结构、复种指数和人均耕地面积对人均粮食占有量的变化影响从高值区向东西两侧递减。河西走廊水资源短缺，生态环境脆弱，发展粮食生产应处理好粮食生产、经济社会发展与生态保护的关系，在生态安全的前提下促进粮食生产稳定发展。此外，统筹考虑自身发展规模与资源环境状况，发展一定规模的草畜、经济作物，有条件的县域，注重产粮大县的建设，政府政策、资金对其进行扶持，保障产粮大县以及粮农的利益。

Abstract:

Grain security is a national strategy that is related to economic development, social stability and national independence. China′s government explicitly proposed new grain security strategy, that is "taking the initiative, focusing on domestic, making sure the production capacity, moderate import, and technical support". Taking 20 counties as research units in Hexi Corridor, using the methods of ESDA and geographically weighted regression (GWR) model, the article analyzed the evolvement of spatial-temporal patterns and its driving factors of per capita grain possession. The results showed that the change characteristics of per capita grain possession fluctuated, i.e. rising, declining, and rising again from 1990 to 2014. Low production but fast growth was the main pattern in the county level of per capita grain possession, and grain production function was more obvious in Zhangye, Yongchang county and Liangzhou district where were in the middle and east of the Corridor. Overall spatial correlation of per capita grain possession increased and the state of high-high cluster pattern and low-low cluster pattern heightened. Among the driving factors of per capita grain possession change, plant structure > multiple cropping index > per capita cultivated area > yield per unit area > nonfarm employment > per capita GDP. Driving factors had transitional and spatial differentiation characteristics. The change of yield per unit area, nonfarm employment and per capita GDP impact on per capita grain possession had spatial differentiation characteristics, and the impact of plant structure, multiple cropping index and per capita cultivated area declined as the high value area to the east and the west sides. Finally, it suggested that because of the water resource shortage and vulnerable ecological environment in Hexi Corridor, for the grain production it should balance the relationship among grain production, economic and social development, and ecological protection, develop a certain scale of pasture grass, livestock and cash crops, and pay attention to construct major grain-producing counties. The Government policies and funding should protect the interests of grain farmer and major grain-producing counties.