1985—2015年中国县域芝麻生产的时空演变

为阐明我国芝麻生产的时空变化特征，基于1985—2015年的我国县域芝麻生产统计数据，采用集中度、重心迁移、产量贡献率、优势度等指标，对我国芝麻种植面积、产量和单产的时空动态变化进行分析。结果表明:1)1985—2015年，我国芝麻产量和面积的分布基本一致，主要集中在大别山山脉一带和辽宁省西北部；全国芝麻单产水平不断提升，种植面积自2000年起小幅缩减，而产量变化处于明显的波动状态。2)30年间，全国芝麻产量集中度和面积集中度变化波动较小，集中地区分布发生了一定的变化；我国芝麻产量、面积重心同步向南偏西方向迁移，迁移距离分别为252和344 km。3)我国芝麻生产的主导因素一直为面积，占比为40.0%—49.9%；我国芝麻的生产优势区主要在河南、安徽、湖北、江西四省。近30年来，我国芝麻种植变化受其自身特性、病虫害、湿害以及政策等影响，芝麻生产受到一定的限制。因此，优化和调整我国芝麻生产的政策倾向、种植结构、良种研发以及栽培管理等方面尤显关键。

Spatio-temporal evolution of sesame production in county-level areas of China during 1985-2015

To clarify spatial-temporal change characteristics of sesame production in China, based on county-level statistics of national sesame production from 1985 to 2015, the spatial-temporal variations of sesame planting area, production and yield in China were analyzed by using the indexes of concentration, migration of gravity center, production contribution rate, dominance and so on. The results showed that: 1)The production distribution of sesame in China from 1985 to 2015 was consistent with the area distribution, mainly concentrated in the Ta-pieh Mountains and northwest Liaoning Province. The level of the national sesame yield was constantly improving. On the contrary, the planting area has reduced slightly since 2000. Moreover, the variations of production were in a state of obvious fluctuation. 2)In recent 30 years, the national sesame production concentration and area concentration varied little, but the distribution of concentrated areas displayed certain changes. The center of gravity of sesame production and area migrated 252 and 344 km southwest, respectively. 3)The dominant factor of sesame production in China was area, and the proportion ranged from 40. 0% to 49. 9%. The production advantages areas of sesame in China were mainly in Henan, Anhui, Hubei and Jiangxi provinces. In the past 30 years, the variations of sesame production in China were mostly affected by its own characteristics, pests, wet damages and policies. Hence, the sesame cultivation was restricted to some extent. In conclusion, for the production of sesame seeds in China, the key factors are policy tendency, planting structure, seed research and development, and cultivation management.