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大气污染对水稻产量的影响研究

时间:2018-08-10 09:23来源:毕业论文
通过各地统计年鉴及气象局网站,收集我国水稻主要生产区内10个站点2000-2012年的历史水稻产量、水稻关键生育期内的日均温、月降水量和大气污染指数(API)资料,利用气候倾向率和一阶

摘要:大气污染不仅对人类的健康有很大伤害,对农作物的生长也存在多方面的危害。明确我国大气污染趋势及其对水稻产量的影响,对预测和评估未来大气污染对我国水稻生产的影响具有重要的意义。本研究通过各地统计年鉴及气象局网站,收集我国水稻主要生产区内10个站点2000-2012年的历史水稻产量、水稻关键生育期内的日均温、月降水量和大气污染指数(API)资料,利用气候倾向率和一阶差分法分析了各站点API的变化趋势,并采用5年线性调和滑动平均方法与一元回归方程式确定了水稻的趋势产量和气候产量;计算了各地水稻主要生长期内有效积温(GDD)、总降水量(P)和平均API值。在此基础上,进一步采用多元回归模型分析了水稻气候产量与GDD、P和平均API值之间的定量关系,确定了API变化对水稻产量的影响率以及贡献率。结果表明,各站点API均呈下降趋势,API 对水稻气候产量的平均影响率为-1.11%, 贡献率的平均值为3.36%,各站点贡献率绝对值达到38.76%,说明API是影响水稻生产的重要因素。空气污染在一定程度范围内,由于散射辐射的“肥料效应”以及气溶胶的降温效应,API的增加会提高水稻产量,但超过一定范围,就会带来水稻产量的降低。26813
毕业论文关键字:大气污染;API;水稻;产量;影响率;贡献率
Statistical Analysis of the Impact of Air Pollution on Rice Yield
Abstract: Air pollution has great harm not only to human health, but also to the growth of crops. Studying the effect of air pollution on rice yield in China is significant to evaluating and forecasting that on rice production in China. This study collected the historical rice, the daily average temperature, monthly precipitation and air pollution index (API) data in the key growth period of rice yield of 10 sites in 2000-2012 through statistical yearbooks and weather bureau website of each station. The trend of average API, the correlation between average API and rice yield was analyzed by climatic tendency rate and first difference method. And the trend yield and climatic yield were determined by the methods of 5 linear harmonic moving average method and simple regression. Based on GDD, P and average API during rice’s key growth periods, the relational expression of them and rice climatic yield was found by multiple regression model. Then API’s effect rate and contribution rate to rice climate yield of each site were analyzed. The results show that the average API of each site is declining. The influence rate of average API on rice yield is -1.11%, and the average contribution rate is -0.95%, but the absolute values of it is as much as 38.38%, which means air pollution is a vital factor of rice production. In a certain range, for the ‘fertilizer effect’ of diffuse radiation and the cooling effect of aerosols, the increase of average API will bring about the rise of rice yield, but it will lead to the decline of rice yield beyond that range.
Key words: air pollution; API; rice; yield; influence rate;contribution rate
目  录
摘要1
关键词1
Abstract1
Key words1
引言(或绪论)1
1 材料与方法2
1.1 研究区域及数据来源2
1.2数据处理3
1.3 统计分析3
1.3.1 API的变化趋势3
1.3.2 API与产量的相关性3
1.3.3 API对水稻产量的影响率3
1.3.3 API对水稻产量的贡献率4
2 结果与分析4
2.1 API的变化趋势分析4
2.2 API与水稻产量的相关性分析4
2.3 API对水稻产量的影响率5
2.4 API对水稻产量的贡献率5
3结论与讨论 6
致谢7
参考文献7
大气污染对水稻产量的影响
近年来,大气污染问题已受到人们的广泛关注,它不仅影响着人类的身体健康,还会抑制农业生产的发展。大气污染物可大致分为两大类:颗粒污染物与气态污染物[1],其中以颗粒物更为普遍且危害较大。当前颗粒物污染的研究热门是气溶胶污染,大气气溶胶是指大气与悬浮在其中的固体和液体微粒共同组成的多相体系,直径多在10-3-102μm之间。根据成分来源主要分为自然源气溶胶(火山灰和沙尘类)和人为源气溶胶(硫酸盐类、氮化物类等)[2]。近年来成为社会关注焦点的霾天气就是气溶胶(颗粒物)本身的物理特征和化学成分消光引起的大气能见度下降的现象。 大气污染对水稻产量的影响研究:http://www.youerw.com/shengwu/lunwen_21103.html
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