非洲粮食产量波动时空格局的定量化研究  

Spatial-Temporal Patterns and Regional Differences of Cereals Production Fluctuation in Africa

作　　者：杨艳昭[1] 吴艳娟[1,2] 封志明[1] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国科学院大学,北京100049

出　　处：《资源科学》2014年第2期361-369,共9页Resources Science

基　　金：中国科学院地理科学与资源研究所"一三五"战略科技计划项目(编号:2012SJ001)

摘　　要：本文采用经验模态分解方法,从洲际、区域、国家等多个尺度,定量分析了1980-2010年非洲粮食产量波动的时空格局,并通过比对粮食产量与粮食单产和播种面积的拟合度,探讨了近30年来非洲粮食产量波动的主要影响因素。结果表明:①1980年以来,非洲粮食产量总体呈上升趋势,短期波动以3年周期为主,长周期约为10年;粮食单产为非洲粮食产量短期波动的主要影响因子;②就各个地区而言,南非地区粮食产量短时间序列波动周期相对较长,为3.75年,并呈缩短趋势;其他各地区短期波动周期均在3年左右,与非洲整体波动水平相近;从长时间序列看,东非长周期时间序列最长,约10年,并呈变长趋势;南非地区次之,约为7.5年;北非和中非地区居末,约为6年;除北非粮食产量波动主要受播种面积影响外,其他地区多受粮食单产影响较大;③就国家水平来看,非洲约71.15%的国家粮食短时间序列波动周期在3年左右,与非洲整体水平相当;非洲绝大部分国家长时间序列波动周期低于10年,强于非洲整体水平;粮食产量水平越高的国家,其粮食产量的波动越小,反之亦然;占非洲耕地64.42%的31个国家粮食产量短期波动主要影响因子为粮食单产,少部分国家为播种面积。Using the empirical mode decomposition （EMD） method and 30 years of FAO data, we decomposed the data for per capita cereal yield and cultivated land and analyzed the fluctuation of cereal production and causes in Africa from 1980 to 2010 at the continental, provincial and national levels. We found that cereal production has increased continually since 1980, and there was an obvious regularity in temporal-fluctuation and spatial-concentration of cereals production. The fluctuation of cereal production had 3-year and 10-year timescales. Regarding short timescales, northern Africa had the longest fluctuation timescale; fluctuation in this area had weakened in recent years. Western Africa had the same fluctuation timescales as Africa, and the rest of Africa had a similar fluctuation timescale of 2.73 years. Regarding long timescales, western Africa had no long timescales, eastern Africa had the same timescales as Africa, fluctuation in this area was longer in recent years. Southern Africa had a 7.5 years timescale, northern and middle Africa had the same timescales of 6 years. Except for northern Africa, per capita cereal production was the controlling factor of short timescale fluctuation. The majority of African countries＇ fluctuation were similar to the African short timescales, and all countries＇ fluctuation were stronger than the African long timescale. The higher level a country can produce cereals, the smaller its fluctuation will be, and the lower level a country can produce cereals, the larger its fluctuation will be.

关 键 词：非洲 粮食产量波动 EMD 空间格局 

分 类 号：F316.11[经济管理—产业经济] F34F224