中国食物供给能力分析

从中国各类型生态系统(农田、草地、水域) 的实际的食物生产能力出发,结合进出口产品中的食物部分,得出全国实际的食物供给能力,根据食物营养成分表中的转化率,将各类食物折算成人类生存所需的3 大营养成分(热量、蛋白质、脂肪) 的产量来表示,并利用ArcGIS 进行草地和农田食物供给的空间分析。以2004 年为例,中国实际食物供给能力为：热量1.601×10¹⁵ kcal,蛋白质6.163×10⁷ t,脂肪2.717×10⁷ t。其中,中国内陆生态系统实际可供给热量1.454×10¹⁵ kcal,蛋白质4.996×10⁷ t,脂肪2.074×10⁷ t,分别达到了陆地生态系统生产潜力的32.46%、38.33 %和41.12%,内陆生态系统食物供给还有较大的增长余地。在小康水平下,中国的食物热量、蛋白质、脂肪分别可以供养人口19.12 亿,20.84 亿和11.03 亿人,按照2010 年营养目标和2020 年全面小康目标,热量和蛋白质的供给已经较为充足,而脂肪的供给有所不足,今后需要注重油脂作物的种植和生产。结果还表明：中国的食物供给能力中,农田占据了绝大部分,不过比例有下降的趋势,从1998 年的84.66%,下降到2004 年的74.72%;草地和水域生态系统所提供的食物所占比例分别为4.83%~5.80%、6.02%~7.51%,波动较小;净进口食物所占比例逐年增长,1998 年仅为4.04%,2004 年增加到13.82%。通过平衡模型计算,在温饱、小康、富裕水平下,2004 年中国可以供养的人口分别为：15.34 亿,15.00 亿和14.11 亿,这表明,如果能够优化种植结构,合理配置植物性食物向动物性食物转化比例,均衡营养消费结构,中国实际食物供给较为充足。     

中国西南—东南季风交汇区降水时空格局变化及其对食物产量的影响

全球气候变化背景下,降水格局改变食物供给将是人类当前和未来所面临的重大挑战,但很少有研究揭示食物供给随降水格局变化的关系。研究中国西南、东南季风共同作用区的降水与食物供给变化,对厘清该区降水与食物供给的动态关系、实现区域粮食安全、保障西南边疆稳定、落实区域民族政策、建成全面小康社会等具有重要意义。文章以中国西南地区的云南省为例,刻画了1988—2018年降水变化格局,并探讨了其对食物产量的影响。结果表明：① 云南省降水时间格局分为：Ⅰ降水丰沛期（1988—2004年）、Ⅱ降水偏少期（2005—2015年）、Ⅲ降水恢复期（2016—2018年）等3个降水时段;② 第Ⅰ~Ⅱ时段,全省降水发生显著变化区域为15.07%,第Ⅱ~Ⅲ时段为13.87%,第Ⅰ~Ⅲ时段为16.53%;③ 全省水平上,降水与食物产量具有显著正相关关系（p<0.01）,且粮食产量与各时间段降水相关系数高于肉奶产量;④ 当降水≥1500 mm时降水量快速下降,粮食产量保持稳定、700~1500 mm时降水量与粮食产量同为小幅下降、≤ 700 mm时降水量小幅下降,粮食产量大幅波动下降。总体而言,1988—2018年云南省降水格局发生了明显的变化,且在不同区域对食物供给产生了显著影响,故亟待划分全省范围的食物产量对降水响应的空间区划,以此来应对日益加剧的降水格局变化。     

“一带一路”沿线国家土地资源承载力的时空格局——基于营养需求分析

“一带一路”沿线国家是全球主要的人口集聚区和食物生产区，从热量、蛋白质和脂肪营养当量视角开展土地资源承载力研究，可为沿线地区改善食物供给状况提供参考。基于营养素转换模型和土地资源承载力模型，从全域到国别研究了沿线国家土地资源承载力的时空格局。结果表明：1995—2019年期间，（1）沿线国家蔬果和蛋奶类食物增幅超过或接近1倍，3种营养素供给量增幅均超过50%，但动物性食物蛋白质供给比例与发达国家仍有一定差距（；2）土地资源承载力增至50亿～60亿人区间水平，约80%国家土地资源承载力在提高，主要集中于东南亚、南亚地区，而中东欧部分国家可载人口有所下降；（3）沿线国家土地资源整体上转入盈余状态，约60%国家土地资源承载指数下降，50%国家人口超载，超过50%的国家热量和蛋白质供应不足。     

基于地理加权回归的中国灰水足迹人文驱动因素分析

根据Hoekstra和Chapgain提出的污染物吸纳理论,估算了2012年全国31个省（区、市）的灰水足迹,采用空间自相关分析方法探讨了2012年中国灰水足迹的空间分布特征,通过构建基于地理加权回归的STIRPAT模型,测算了人口和富裕等人文因素对灰水足迹的影响。结果表明：中国灰水足迹存在较强的空间正相关性和空间分布不均衡性;人文因素对水资源环境的威胁大小排序,依次为城市化率、人口数量、产业结构和富裕程度,其中,城市化率、人口数量、农业比重和人均GDP每提高1%,分别引起灰水足迹增加1.03%、0.85%、0.63%和0.52%;人文因素对灰水足迹的影响存在空间差异,人口对灰水足迹的影响由北向南逐步加大,富裕对灰水足迹的影响由西向东逐渐减小,农业和城市化对灰水足迹的影响由南向北逐步增大;在现有样本范围内,计算结果有条件地支持环境Kuznets曲线。     

青海东部史前人口-耕地变化及其对植被演变的影响

集成青海东部考古数据和DEM,利用面积和墓葬相结合的估算法计算了区域史前人口数量,并利用GIS工具重建史前区域耕地面积的时空格局。结果表明:新石器马家窑文化时期区域人口、耕地迅速增加,并在晚期马厂时期达到新石器的顶峰,人口总数接近4万人,耕地面积达到462 km2,人口和耕地主要分布在黄河—湟水谷地内;齐家时期人口和耕地有一定幅度下降,在青铜时代人口和耕地有显著回升和增长,人口总数达61 000余人,耕地面积达到1 076 km2,约占区域适宜耕地总数的1/10。伴随人口与耕地的变化,人类活动的环境效应也逐步显现,5~4 ka B.P.人类活动导致研究区河谷地带乔木的减少,伴人植物增加,尤其是禾本科含量有较大幅度增加,与当时的粟作农业关系密切;4 ka B.P.后大范围的乔木减少是气候变化结果,其后人类活动加强,加速了乔木覆被面积的萎缩。     

关中盆地生态系统服务的权衡与协同关系动态分析北大核心CSCDCSSCI

测算2000-2012年关中盆地的净初级生产力(NPP)价值量、土壤保持价值量和食物供给价值量,通过引入玫瑰图来研究不同土地利用类型中生态系统服务的时空差异,进而探究三种生态系统服务的权衡和协同关系,并分析其在近13年间的动态变化特征,最后研究土地利用变化对生态系统服务权衡和协同关系的影响来探究其驱动机制。结果表明:(1)研究区NPP单位面积年均价值量约为1720.495元/hm^2,土壤保持单位面积年均价值量约为768.889元/hm^2,食物供给单位面积年均价值量约为167.874元/hm^2。从空间角度分析,NPP和土壤保持的高值区均分布在盆地边缘的山地,低值区集中于盆地中部,而食物供给呈相反格局。从时间角度分析,三种生态系统服务均呈现增加的趋势。2000-2012年,NPP单位面积价值量增幅为21%,土壤保持单位面积价值量增幅为46.7%,食物供给单位面积价值量增幅为245.7%。(2)NPP与土壤保持呈现协同关系,而NPP与食物供给、土壤保持与食物供给呈现权衡关系。(3)13年来关中盆地生态系统服务呈现冲突加强协同减弱的趋势。具体而言,NPP与土壤保持的协同关系表现出明显的下降趋势,NPP与食物供给的权衡关系逐渐增强,而土壤保持与食物供给的权衡关系在13年间基本保持稳定状态。(4)从土地利用变化的角度看,研究区生态系统服务权衡增加协同减少主要归因于耕地和林地的大量减少。同时,权衡土地资源利用中各类冲突对于土地资源的优化使用也有重大的意义。     

中国省域生态系统服务足迹流动及其影响因素

区域间由供给与消费不均衡所引起的生态系统服务流动,逐渐成为新的研究热点。选取具有代表性的食物供给服务、淡水供给服务和固碳服务,运用生态系统服务足迹算法和多区域间投入产出模型,核算中国省区典型生态系统服务足迹和省域间的动态流动以及影响因素。研究表明：中国省域人均食物供给服务足迹为1.16 hm²/人,人均淡水供给服务足迹为0.06 hm²/人,人均固碳服务足迹为2.92 hm²/人,但由于人口数量、地区发展和单位能耗等因素的影响而具有明显的区域差异性,因此供给与需求的不均衡导致了服务足迹在空间上的流动。同时,生态系统服务足迹与各影响因子呈正相关,表明生态环境与经济增长的可持续发展转好的拐点还未出现。     

全球食物供给非均衡性演变及贸易影响

降低食物供给的非均衡性是实现“零饥饿”的重要途径。论文在分析1986—2018年全球食物生产时空演变特征的基础上,基于洛伦兹曲线和锡尔系数,对全球与区域食物生产非均衡性及贸易影响进行了测度。结果表明：① 1986—2018年,全球各类食物产量均呈增加趋势,产出结构发生了显著变化,谷物在植物性食物中的比重减小,油料、蔬菜和水果所占比重增加。不同区域和国家食物营养来源具有显著差异,且尺度越小,差异越大。② 谷物、糖料和水果生产的集中程度相对较低,蔬菜、油料、薯类、水产品生产集中程度较高。豆类、蔬菜、油料、糖料和嗜好类人均产量非均衡性呈增加趋势,薯类、水果、畜禽类和水产品的人均产量非均衡性呈降低趋势。人均热量产出非均衡较低,脂肪和蛋白质产出的非均衡性较高。③ 贸易对全球人均食物及营养供给的非均衡性具有显著的降低作用,且其影响程度逐年增加。贸易对糖类、油料和嗜好类非均衡性降低作用最显著,对脂肪供给非均衡性的降低作用较大。制定以营养为导向的食物生产和贸易政策,对提升食物供给均衡性具有重要意义。     

1990-2011 年山东省旅游节庆的时空变异特征及机理

以山东省为研究区域, 运用半变异函数、克里格空间插值等地统计学分析方法, 分析了1990、1999、2005、2011 年4 个时间点上旅游节庆活动的时空分布规律、结构特征及变异性, 并建立了拟合模型。结果表明:① 旅游节庆数量空间不均衡显著, 总体上呈现出“东高西低”的“三级阶梯状”分布格局;② 空间结构特征明显, 正负相关并存, 并随滞后距离的增加, 正相关性削弱, 负相关性增强;③ 与1990 年相比, 2011 年基台值增加了20.61 倍, 变程值由115.5 km增至335 km, 结构方差比则由69%下降至26%, 随机性因素的影响减弱, 而结构性因素的作用增强;④ 所有方向的分维数值呈下降趋势, 其空间差异性增大, 且全方向和东—西方向的差异性最大, 其余方向相对均衡, 其发展空间格局的板块状异向性分布特征明显;⑤ 经济发展水平、旅游供给能力、交通可达性是引起山东省旅游节庆差异演化规律的3个主要因素。     

中国蔬菜生产的农业物质投入及其潜在风险评价（英文）

由于蔬菜需求量的增加,中国的蔬菜产量不断增加;然而蔬菜地的化学污染会威胁到中国的食品安全。基于蔬菜和粮食作物的播种面积和产量、农业生产投入价格指数、单位面积的农业物质投入、蔬菜和粮食作物生产者价格指数和净利润等数据,本文计算分析了蔬菜地污染造成的中国潜在食品安全风险的变化趋势。研究表明,由于改革开放以来对蔬菜饮食的公共需求的不断增加和蔬菜高的市场价格,蔬菜的播种面积和产量显著增加;然而由于研究时段内蔬菜种植比例的增加,农业物质投入增加所带来的潜在污染风险也在不断增加。通过控制蔬菜地污染,中国的食品安全问题可以得到较大改善。     

食品安全导向下的都市农业发展模式——以北京蔬菜生产为例

随着人们生活水平和认知能力的不断提高,人们对健康的关注和需求也变得更加强烈,因此伴随着近年来食品问题的频繁曝光,食品安全已成为社会各界最关心的议题,其中,蔬菜和牛奶等易腐食品更成为首要关注点。都市农业拥有“近距离短环节”的优势,应当成为城市蔬菜供应的重要渠道和保证城市居民蔬菜安全的主角。本文以北京为研究案例,针对食品安全导向下的城市蔬菜发展模式进行了研究。首先通过解析北京生鲜蔬菜的供应来源,总结了“长距离多环节”农业存在的蔬菜安全问题及都市农业在保证生鲜蔬菜品质安全方面的诸多优势。接着分析归纳了保证蔬菜品质安全下的几种都市农业发展模式,并以典型案例研究的方式分析了各模式的产生背景、运行管理特点。最后提出了促进都市农业发展的保障机制。     

A Study of Food Waste in the Catering Industry in Beijing

Currently, the topic of food waste and its environmental impacts is attracting increasing attention among academic researchers. Based on an investigation of restaurants in Beijing, this study analyzes the quantities, structures, characteristics and costs of the agricultural resources related to food waste in the catering industry in Beijing. The results show that: (1) The average food waste per capita per meal is about 75.02 g (raw) for food away from home among Beijing urban residents, which means that about 10.52% of the food is wasted. (2) According to the quantitative ranking of different categories of food waste, vegetable is the most wasted, followed by meat, aquatic products, and grains. The foods in the other categories are wasted much less. (3) Food waste is affected by the restaurant type, as well as the number, gender, age, education level, and consumption motivation of the consumers. (4) Based on the estimated food waste per capita, about 417.92 thousand tons of food is wasted annually at the consumption stage in the catering industry in Beijing. This food waste amount is equivalent to approximately 765.53 tons of cereals which are wasted, and this represents 79.66% of cereals production and 13.15% of cereals consumption in Beijing. Estimated by the required land use, this amount of food waste means that the total production of approximately 166.12 thousand ha of arable land is being wasted in Beijing.     

气候变化背景下未来西藏粮食供需平衡状况预测

基于组合预测法、生产函数和笔者前期关于气候变化对西藏粮食产量定量影响的工作,对考虑气候变化影响的未来西藏县（区）级尺度粮食供需平衡状况进行预测。结果表明：① 西藏粮食产量较高的区域集中在一江两河等河谷地带,西藏粮食需求量较大的地区主要在人口较多的县市,未来肉类消费增加将会消耗更多的饲料用粮。② 西藏粮食供需平衡状况南北分异明显,南部河谷地区相对较好,北部羌塘高原较差。③ 当前西藏不能实现考虑口粮、饲料粮、工业用粮、种子用粮和损耗5种需求总和的粮食供需平衡,全区自给率为70.58%,2030年和2050年分别下降至62.59%和53.55%。虽然西藏总需求不能完全自给,但仍能保障口粮自给。④ 气候变化整体上对自给率为正面影响。到2030年和2050年,气候变化将使自治区粮食自给状况提升2.45%和2.09%。研究有助于掌握未来西藏粮食安全状况,规划农业布局,以期保障边疆粮食安全、促进高原农业可持续发展。     

Unexpected Results from China's Agricultural Subsidies Policy

Given the huge demand for food created by China's large population and the high cost of transporting food across such a large nation, a food security strategy based on local self-sufficiency seems vital. To encourage agricultural production, agricultural subsidies have therefore been implemented since 1997. Although subsidies to support food production in China arose from the desire to combat poverty and hunger, they may have instead led to adverse health impacts, food insecurity, and environmental degradation because the complexity of socioeconomic systems prevented governments from fully understanding the relationships among the many factors in such systems. China therefore faces enormous challenges before it can attain sustainable food production at levels high enough to end hunger, without undesirable consequences.     

Handbook of applied spatial analysis: software tools,methods and applications,edited by M.M. Fischer and A. Getis

With the rising oil prices, climate change, and the ever increasing burden of nutrition-related disease, food security is of growing research interest in academic disciplines spanning agronomy to epidemiology to urban planning. Some governments have developed progressive policies encouraging individuals to consume locally produced foods in order to support local economies, improve agricultural sustainability and community access to food, and to plan and prepare for adverse environmental impacts on food security. However, fundamental methods are lacking for conducting research on food security across these various disciplines. In this article, we first present a method to measure agricultural self-sufficiency, which we refer to as our self-sufficiency index (SSI) for the province of British Columbia, Canada. We then present a Bayesian autoregressive framework utilizing readily available agricultural data to develop predictive smoothing models for the SSI. We find that regional capital investment in agriculture and cropland acreage is the strong predictor of SSI. To accommodate spatial variability, we compare linear regression models with spatially correlated errors to less traditional spatially varying coefficient models, and find that the former class results in better model fit. The smoothed maps suggest that relatively strong self-sufficiency exists only in subset clusters in the Okanagan, Peace River, and lower mainland regions. In spite of policy to promote local food, the existing local agricultural system is insufficient to support a large-scale shift to local diets. Our approach to estimating neighborhood-based self-sufficiency with a predictive model can be extended for use in other regions where limited data are available to directly assess local agriculture and benefit from explicit consideration of spatial structure in the local food system.     

Understanding Agriculture Production and Food Security in Ethiopia from the Perspective of China

Food security and sustainable agricultural development are the hot issues of scientific research, especially after the population affected by hunger surprisingly increased in 2016. Long-lasting and recurrent famines caused by natural disasters and wars have afflicted Ethiopia. Unlike Ethiopia, which is still struggling to achieve food self-sufficiency, China managed to quickly become food self-sufficient at a rapid speed, despite the fact that it also faced the same challenges of famine over the last century. In the backdrop of differing environmental and socio-political challenges the two countries face, comparing the similarities and differences between the two countries will yield important lessons and insights for Ethiopia to follow to achieve food self-sufficiency. Here, the progress towards food security in Ethiopia and China is presented to quantitatively compare the gap of agricultural production between both countries. We found that food production in Ethiopia is heavily constrained by drought, soil degradation, climate change, out-dated agricultural production technologies, and poverty. According to these challenges, we examined corresponding responses in China to propose solutions for achieving food self-sufficiency in Ethiopia, given the realities of its unique national situation.     

基于粮食安全的中国能源可持续发展:机遇和挑战(英文)

中国能源安全形势日益严峻,机遇与挑战并存。生物质能发展具备资源丰富、产品多元化、循环利用和增加农民收入的显著优势,加快生物质能开发对保障中国能源供给安全极为重要。本文通过运用灰色关联分析方法,对中国生物质能开发与粮食安全之间的关系进行定量评价。结果显示我国生物质能开发对粮食安全的影响并不明显,中国的粮食安全主要受其农业生产条件限制。但这并不意味着中国生物质能可以不受限制的发展,中国发展生物质能需综合平衡多种因素,如短期内大量投资、生物质供应的激烈竞争。清洁、可持续是中国生物能源发展的重要方向。     

China’s food security situation and key questions in the new era: A perspective of farmland protection

As the world’s largest developing country, the ability of China’s agricultural resource utilization to effectively support the current and future food security goals has been affected by a variety of factors (e.g., transformed supply channels, tightening international situation and frequent emergencies) in recent years and has attracted extensive attention from the academic community subject to multiple factors. This study uses literature review, statistical analysis, and spatial analysis methods to systematically explore China’s food security situation in the context of farmland resource constraints. It is found that the demand-side pressures such as demographic changes, social class differentiation, and dietary structure adjustments derived from economic growth and rapid urbanization have placed extremely high expectations on food supply. However, the quantitative restrictions, utilization ways, and health risks of farmland resources on the supply side constitute a huge hidden concern that affects the stability of food production. Although China’s farmland protection system is undergoing a transition from focusing on quantity management to sustainable use, the matching and coordinating demand pressure and supply capacity for food security is unbalanced. Therefore, facing uncertain future development scenarios, policymakers should focus on building a resilient space for China’s farmland protection to withstand the interference of major emergencies. The existing farmland protection space policy can be integrated by establishing a national farmland strategic reserve system (based on resilient space), and further development of targeted use control measures for zoning, grading, and classification will help realize sustainable China’s farmland resources use.     

Conceptualising the Migration–Food Security Nexus: Lessons from Nepal and Vanuatu

In the past decade, international development practitioners have increasingly argued that migration improves the food security of households at origin, by providing the capital necessary for agricultural intensification or food purchase. These debates have occurred largely in isolation from a discussion of the values that underpin food production and consumption in the communities that migrants call home. We question the assumption that a shift from an agricultural-based economy to an economy based on remittances increases the ability of communities to secure access to food in the face of rapid economic and cultural change. In this paper, we present two independently conducted studies from Nepal and Vanuatu that investigate the impact of out-migration on local perceptions of agricultural and residential land and the meaning given to food security. Our data reveal that the value changes associated with large-scale out-migration have the potential to make the agricultural sector at origin more vulnerable, unproductive, unsustainable or unattractive, leaving a longer-term impact on food security. We offer some reflections on the implications of these findings for the structure of the migration–food security nexus.     

城市边缘区耕地面积变化时空特征及其驱动机制——以北京市顺义区为例

城市边缘区的土地资源紧缺而利用方式多样,土地利用变化既与城市发展有关又和粮食安全密切联系,因此加强城市边缘区的土地利用研究既必要又迫切。利用1990年和2000年TM影像获取的土地利用数据、 1991~2002年社会经济统计数据,借助GIS空间分析方法以及数理统计方法,系统探讨了北京市顺义区耕地流失的时空格局特征及其驱动机制。结果显示,1990~2000年顺义区流失耕地的57%转为建设用地,43 %转为生态用地。农用地中粮食作物的种植面积大幅减少,菜地和果园面积快速增加。工业发展是耕地流失的第一驱动力;人口城市化、房地产发展等加速耕地流失。