亚洲耕地利用格局十年变化特征研究

【目的】亚洲作为全球人口最多、耕地面积最大、发展中国家众多的大洲,其耕地利用格局变化特征关系到各国乃至全球的粮食产量波动,影响世界粮食安全。本研究旨在通过分析亚洲耕地利用格局变化,加深对亚洲耕地利用现状的认识,科学把握其变化特征及规律,为亚洲的农业土地系统研究提供依据。【方法】采用中国最新研制的2000年和2010年两期全球30 m地表覆盖遥感数据产品(GlobeLand30)及FAOSTAT统计数据,建立耕地面积数量和耕地利用格局指标群,选取耕地面积及其变化幅度、复种指数及其变化幅度、耕地破碎度及其变化幅度等指标,在国家、地理分区和县级等三个尺度上,综合分析2000—2010年亚洲耕地的数量、复种指数及耕地破碎度变化特征。【结果】2010年亚洲耕地面积69 827.94×104 hm2,10年间面积增加62.62×104 hm2,增幅达到0.09%。除东亚耕地数量减少外,其他区域耕地增加;东南亚耕地涨幅最大,西亚是耕地增减最为活跃的地区。亚洲有60%的国家耕地增加,80%的国家耕地面积变化幅度为-5.00%—5.00%。2000—2010年,亚洲复种指数提升7.77%,增幅达9.00%,五大地理分区的复种指数均呈现增加状态。超过2/3的国家耕地复种指数增加,沙特阿拉伯、卡塔尔、塞浦路斯等国家耕地复种指数减少明显。亚洲耕地地块细碎的区域主要集中在中国南方、日本、菲律宾、阿富汗,而印度、中国华北平原及东北农垦区则耕地连片、地块大。亚洲耕地破碎度总体上增加1.12%,中亚和南亚耕地破碎度大幅下降,东南亚耕地破碎程度加剧。超过半数的国家耕地破碎度降低。2000—2010年,中国耕地面积减少0.95%,复种指数增幅较大,达到6.01%,耕地破碎度小幅增加,增幅达2.17%。中国南方地区耕地破碎度高,华北平原、东北农垦区、成都平原等粮食主产区耕地破碎程度低;东部及华北经济发达地区耕地破碎程度增加剧烈;湖南、江西等地耕地破碎度降低。【结论】总体来说,亚洲耕地面积变化平稳,略有增加。复种指数分布呈现"南高北低"的特点,复种指数变化"东南增西北减",耕地利用程度有较大提升。亚洲的耕地破碎度10年间略有增长,半数以上国家的耕地向规模化发展。中国作为亚洲农业重点区域,10年间其耕地数量减少并伴有破碎化加剧的趋势,但耕地利用率大幅提升。

Changes of Cultivated Land Utilization Pattern in Asia from 2000 to 2010

【Objective】Asia has the largest population, the biggest cultivated land quantity, and a lot of developing countries. The change characteristics of Asian cultivated land utilization are related to national and global grain production fluctuation, and impact on world food security. By analyzing Asian cultivated land utilization pattern change, the understanding of Asian cultivated land utilization pattern was deepened, the change characteristics and laws were mastered scientifically. It provides the basis for Asian agricultural land system research.【Method】Based on the FAOSTAT statistics data and the latest China''s 30 meter resolution global land cover data product (GlobeLand30) in 2000 and 2010, two indicator groups were built to analyze the change characteristics of cultivated land utilization pattern in Asia during 2000-2010, including cultivated land quantity indicator group and cultivated land use pattern indicator group. Six indicators which selected from two indicator groups were calculated, including cultivated land area, multiple cropping index and fragmentation index in 2010 and their change percentage during ten years. The change characteristics of cultivated land quantity, multiple cropping index and fragmentation index from 2000 to 2010 were discussed from three scales, including the country level, geographical zones and the county level. 【Result】 Results showed: the cultivated land area of Asia was 69 827.94×10⁴ hm² in 2010; during the past ten years, the cultivated land loss was 62.62×10⁴ hm², and area of Asian cultivated land generally increased by 0.09% with decrease of cultivated land in East Asia and increase of other regions of Asia. The growth rate of Southeast Asia was biggest and West Asia was the most active area of cultivated land increase and decrease. In Asia, 60% of the countries'' cultivated land has increased, and 80% of the countries'' cultivated land has changed from -5.00% to 5.00%. From 2000 to 2010, the multiple cropping index increased 7.77% in Asia, and the change percentage was 9.00%. It also increased in every geographical zones of Asia. More than two-thirds of the countries'' multiple cropping index has increased, but western Asia''s Saudi Arabia, Qatar, Cyprus and other countries have seen a significant reduction. The areas of Asian fragmented cultivated land were mostly concentrated in southern China, Japan, the Philippines and Afghanistan, while India, North China Plain and the Northeast agricultural reclamation area have large parcels. The change percentage of fragmentation index in Asia was 1.12% with increased acutely in Southeast Asia but declined dramatically in Central Asia and South Asia. Over half of countries in Asia had the decreased fragmentation index. In China, during the past decade, cultivated land quantity declined 0.95%, multiple cropping index increased 6.01%, and fragmentation index increased 2.17%. The south region had the high fragmentation index, but main grain production regions, such as North China plain, the northeast land reclamation district and Chengdu plain, had the low fragmentation index. The fragmentation index of economically developed areas in the east and north China increased, but decreased in Hunan and Jiangxi Province. 【Conclusion】 Generally speaking, the change of Asian cultivated land quantity was relatively steady, and the area increased slightly. The multiple cropping index showed high in the south and low in the north. It was a remarkable fact that the growth rate in Southeast Asia was higher than other regions, and the multiple cropping index reduced in northwest of Asia. It was indicated that the cultivated land utilization ratio in Asia had a great improvement. The fragmentation index of Asia increased little in the past decade. Over half of the countries’ cultivated land had the large-scale development. As the key agricultural district of Asia, the cultivated land of China reduced slightly and became more broken, but the cultivated land utilization has increased substantially.