近20年气候变暖对黑龙江省水稻增产的贡献

研究过去的气候变暖对作物产量的影响是认识变暖对农业影响的有效途径,但如何定量区分出气候变化和技术发展对粮食作物的影响程度是目前研究的难点。本文提出的算法在一定程度上可以克服传统算法缺陷,用此方法估算过去20年气候变暖对黑龙江省水稻单产增加的贡献率,结果表明：20世纪80年代相对于70年代水稻单产增加了30.6%,其中由气候变暖带来的增产量占实际增产量的12.8%~16.1%,相当于使70年代的单产增加3.9%~4.9%。20世纪90年代水稻单产较80年代增产42.7%,其中,气候变暖对单产增加的贡献率约为23.2%~28.8%,相当于在20世纪80年代的单产水平上增产9.9%~12.3%。     

中国粮食安全脆弱区的识别及空间分异

In view of food affordability and the threshold for food security, this paper has established an integrated index for assessing the vulnerability of food security in China, which is composed mainly of the balance between food supply and demand, the reserve for food security and the economic capacity for offset food demand. Six types of food security regions are identified based on the data from county-level statistics. At regional scale, China’s food security is not optimistic. Under normal conditions without the emergence of extreme disasters and decline of grain-sown areas, China’s most vulnerable areas (Type VI) account for 30.3% of the total number of counties (cities), which are unable to meet the ends by food productivity or market based measures at subsistence levels. In China, there are only 14.5% of the counties (cities) that could guarantee well-off food security through grain production (Type I) or economic measures to meet the demand by themselves (Type III). According to the different vulnerable levels of food security and its dominant forming factors, vulnerable regions of food security in China could be classified into three categories: (1) Vulnerable regions of food security dominated by natural factors (including Type IV and Type VIa), which account for 39.4% of the total number of counties (cities), mainly located in fragile ecologic zones, i.e., farming-grazing transitional zones in the marginal areas of summer monsoon, the poor hilly areas in southern China and so on; (2) Vulnerable regions of food security dominated by low ratio of grain-sown areas (including Type VIb and Type V), which account for 16.7% of the total number of counties (cities), mostly located in the developed areas in the eastern coast of China; (3) Potential vulnerable regions of food security with underdeveloped local economies (Type II), of which 57% are the main grain-surplus regions in China, mainly located in the areas of plains and basins with favorable climate.     

中国东北农业生产适应气候变化的行为经济学解释

利用调查问卷和入户访谈的方法,以中国东北地区11个调查点为研究区.对554户农户进行调查研究.从行为经济学的视角出发,把农业实践者的粮食种植行为作为一种农业经济行为,分析20世纪80年代气候变暖以来,农业实践者在农业种植决策中的行为过程及其与传统经济学理性行为之间的差异.结果显示,在不确定条件下,农业决策行为符合行为经济学的一般规律,在认知偏差和思维定式等因素的影响下,会系统地偏离传统经济学理论,产生非理性行为,从而导致适应与变化之间存在时滞现象:①受启发式认知偏向的影响,农业实践者在作物种类选择、种植计划制定和粮食出售时间确定等方面均表现为非理性的特点:②受中国具体国情和农业生产固有特点的影响,出于"保障生活能够继续"的考虑,农业实践者判断"获得"和"损失"的参照点通常很低,对作物品种选择的行为更倾向于保守.     

黑龙江省漠河县乡村人群对气候变化的感知方式与认知结果

以中国东北地区漠河县气象站点1960~2005年逐日平均气温数据为参照,通过问卷调查和访谈的方式,探讨漠河县乡村人群感知气候变化的方式与特征,以及认知的形成过程。结果发现:生活活动、生产活动和观察自然现象是漠河县乡村人群感知气候变化的主要途径,其中人群对生活活动的敏感度最高;基于上述感知渠道,乡村人群形成了对当地过去50 a气候变化总体趋势、极端天气现象和四季持续时间的认知。     

乡村人群气候变化感知的初步分析——以黑龙江省漠河县为例

以我国黑龙江省漠河县气象站点1980-2005年逐日平均气温和逐日降水量数据为参照,通过问卷调查和访谈的方式,探讨过去20 a来乡村人群对当地气候变化的感知情况。结果表明：漠河县乡村人群具有较强的气候变化感知能力,对于气候变化趋势的感知相对较为准确,但因受到个体客观背景环境的影响,感知结果存在一定的不确定性;由于可参照时间范围相对较短,人群对变化强度的感知存在一定的片面性;人群能够正确认识气候变化的影响并做出相应的调整,但调整的幅度通常较难把握。