鄱阳湖区水位变化对血吸虫病传播的影响

发布时间：2018-04-01 20:07

本文选题：血吸虫病　切入点：改进的归一化水体指数(MNDWI)　出处：《中国疾病预防控制中心》2008年硕士论文

【摘要】： 我国现有钉螺面积34.2亿m~2,其中江湖洲滩地区的有螺面积占94%以上。这类地区具有“春湿、夏淹、秋露、冬干”的特征,每年洪水上涨时,形成一片汪洋,秋季水退之后,洲滩暴露,植被丰茂,一般每年水淹3-5个月,地面长期保持潮湿,特别是芦苇杂草丛生的洲滩,非常适合钉螺孳生。钉螺的孳生对水有严格的要求,幼螺发育期间离不开水,成螺长期淹于水中则存活率下降,而且水的分布对钉螺生存必需的植被也有很大影响,干旱之处湖草难以丛生,而长期被水淹的地方湖草也可被毁,所以了解洲滩地区水位及水淹变化对于掌握钉螺的分布具有重要意义。随着遥感技术的发展,其在提取湖泊水域范围方面的应用也越来越多,而湖泊水域面积变化很大程度上受水位变化影响,因而在了解水位变化对螺情变化影响的基础上,可运用遥感技术预测洲滩钉螺的分布状况。第一部分试点区的血吸虫病流行状况马家湾及门前滩洲位于星子县蓼南乡渚溪村。该试点区05、06及07年活螺密度分别为4.74、0.85及3.37只/0.1m~2,感染螺密度05年为0.0018只/0.1m~2,06及07年未压出阳性螺,人群感染率分别为3.35%、1.59%及2.31%,耕牛感染率分别为12.31%、3.23%及3.03%。第二部分运用遥感技术分析鄱阳湖区水面面积变化本研究收集1998-2006年间的12景遥感影像,对其进行几何校正,提取MNDWI值,并设定阈值,建立掩膜,然后划定感兴趣区求取鄱阳湖的水面面积。对遥感影像中提取的鄱阳湖区的水域面积与星子、湖口及康山当日的水位进行相关性分析,相关性均较强,相关系数分别为0.957、0.893及0.939,然后以鄱阳湖区水域面积与对应的星子站当日水位建立模型,其中对数模型的拟合效果较好,R=0.959,R~2=0.920,校正R~2=0.912,模型为S=5181.5111n(h)-10261.9,其中S:鄱阳湖区水域面积,h:获取卫片当日星子水文站水位。利用2006年11月6日的TM遥感影像对鄱阳湖主体水域-水位模型进行验证。结果表明,采用模型计算出的水域面积与遥感图像测算的结果相差较小,运用影像提取的水域面积为1658.73km~2,用模型估算的水域面积为1648.20km~2,相差较小,误差小于0.64%。说明运用遥感技术提取的水域面积可以较好地反映鄱阳湖区水位变化趋势,从而为将遥感技术应用于洲滩钉螺分布的预测提供了保证。第三部分小范围研究水位变化对螺情的影响在血吸虫病的传播链中,水是必不可少的载体,且水与钉螺的孳生繁殖是密不可分的,水位的变化对于钉螺分布具有重要影响,有必要对水位变化对螺情的影响展开研究。本研究先从小范围上分析了水位变化对螺情状况的影响,收集星子水文站1997-2007年的水位资料,以分析水位变化对渚溪试点区及星子县钉螺分布状况的影响。经相关统计分析发现渚溪试点区活螺框出现率与星子站上一年度8月份月平均水位间呈负相关,相关系数r=-0.748,p=0.013＜0.05,此外渚溪试点区活螺框出现率还与上一年度丰水期平均水位及年最高水位间呈负相关,结果分别为r=-0.652,p=0.041＜0.05及r=-0.771,p=0.009＜0.01。由此可推测丰水期水位越高,淹水时间越长,钉螺死亡率越高,活螺框出现率越低。此外,星子县湖沼型钉螺面积与星子站4月份月平均水位之间呈负相关,结果为:r=-0.761,p=0.011＜0.05,说明洲滩初涨水期间提前涨水或水位升高,有螺面积减少。第四部分大范围上研究水位变化对有螺面积的影响为了进一步验证第二部分的结果,以星子站月平均水位代表鄱阳湖水位与江西省湖沼型钉螺面积之间进行相关性分析。结果发现江西省湖沼型钉螺面积与鄱阳湖4月份月平均水位呈负相关,r=-0.658,p=0.039＜0.05,进一步说明四月份涨水越晚水位越低则钉螺面积越大。本研究第二部分对遥感影像提取的水域面积与实际的水位信息之间进行了论证,而第三四部分的结果表明查螺前一年8月份的月平均水位及查螺当年4月份的月平均水位高低影响着钉螺的分布及有螺面积,因此在实际应用中可收集4月份及8月份的卫片通过提取水域面积来预测钉螺分布及钉螺面积。
[Abstract]:The existing snail area of our country is 34.200 million m ~ 2 , among which there are more than 94 % of the snail area in the shoal area of the Jianghu . This area has the characteristics of " spring and wet , summer flood , autumn dew and winter " . When the annual flood rises , the shoal is exposed and the vegetation is lush . Generally , the water is watered for 3 to 5 months , and the ground is kept moist for a long period of time .

It is very important to understand the distribution of water level and flood in Zhoutan area . Therefore , it is very important to understand the distribution of water level and flood in Zhoutan area .

With the development of remote sensing technology , its application in extracting lake water area is more and more , and the area of lake water area is greatly influenced by the change of water level , so on the basis of understanding the influence of water level change on the change of water level , remote sensing technology can be used to predict the distribution of snail .

The epidemic situation of schistosomiasis in the first part of the trial area

The densities of living snails were 4.74 , 0.85 and 3.37 / 0.1m ~ 2 respectively . The infection rates were 3.35 % , 1.59 % and 2.31 % , respectively , and the infection rates were 12.31 % , 3.23 % and 3.03 % , respectively .

The second part uses the remote sensing technique to analyze the surface area change of the Lake District of the Lake

In this study , 12 - scene remote sensing images from 1998 to 2006 were collected , the values of MNDWI were extracted , the threshold was set , the mask was established , and then the area of interest in the region of interest was determined .

The results show that the area of water area calculated by using remote sensing technology is 168.73km ~ 2 , and the error is less than 0.64 % . The area of water area extracted by using remote sensing technology is 1648.20km ~ 2 , and the error is less than 0.64 % .

The effect of water level change on the snail ' s condition in the third part

In the propagation chain of schistosomiasis , water is an essential carrier , and the propagation of water and snail is inseparable . The change of water level has an important influence on the distribution of snail , and it is necessary to study the influence of water level change on the snail condition .

In this paper , the influence of water level change on the condition of snail ' s condition is analyzed from a small range , and the water level data from 1997 to 2007 of Xingzi Hydrologic Station is collected to analyze the influence of water level change on the distribution of Ononensis in Zhuxi pilot area and Xingzi county .

The correlation coefficient r = - 0.748 , p = 0.013 & lt ; 0.05 , r = - 0.652 , p = 0.041 & lt ; 0.05 and r = - 0.771 , p = 0 . 009 & lt ; 0.01 , respectively .

In addition , there was a negative correlation between the snail area and the average water level in Xingzi station in April , and the result was : r = - 0.761 , p = 0 . 011 < 0 . 05 .

On the fourth part , the influence of the change of water level on the screw area is studied .

In order to further verify the results of the second part , the correlation between the average water level of Xingzi station and the snail area in the lake of Jiangxi Province was analyzed . The results showed that the snail area in the lake of Jiangxi Province was negatively correlated with the average water level in April , r = - 0.658 , p = 0.039 & lt ; 0.05 , and further indicated that the higher the water level in April , the greater the snail area .

The second part of this study demonstrates the area of water area extracted by remote sensing image and the actual water level information , and the results of the third part show that the average water level in August and the monthly average water level in April of the snail affect the distribution of the snail and the snail area . Therefore , in practical application , it is possible to collect the snail distribution and the snail area by extracting the area of water area in April and August .

【学位授予单位】：中国疾病预防控制中心
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R184

【引证文献】