本文選題：血吸蟲病　切入點：改進的歸一化水體指數(shù)(MNDWI)　出處：《中國疾病預(yù)防控制中心》2008年碩士論文

【摘要】： 我國現(xiàn)有釘螺面積34.2億m~2,其中江湖洲灘地區(qū)的有螺面積占94%以上。這類地區(qū)具有“春濕、夏淹、秋露、冬干”的特征,每年洪水上漲時,形成一片汪洋,秋季水退之后,洲灘暴露,植被豐茂,一般每年水淹3-5個月,地面長期保持潮濕,特別是蘆葦雜草叢生的洲灘,非常適合釘螺孳生。 釘螺的孳生對水有嚴(yán)格的要求,幼螺發(fā)育期間離不開水,成螺長期淹于水中則存活率下降,而且水的分布對釘螺生存必需的植被也有很大影響,干旱之處湖草難以叢生,而長期被水淹的地方湖草也可被毀,所以了解洲灘地區(qū)水位及水淹變化對于掌握釘螺的分布具有重要意義。 隨著遙感技術(shù)的發(fā)展,其在提取湖泊水域范圍方面的應(yīng)用也越來越多,而湖泊水域面積變化很大程度上受水位變化影響,因而在了解水位變化對螺情變化影響的基礎(chǔ)上,可運用遙感技術(shù)預(yù)測洲灘釘螺的分布狀況。 第一部分試點區(qū)的血吸蟲病流行狀況 馬家灣及門前灘洲位于星子縣蓼南鄉(xiāng)渚溪村。該試點區(qū)05、06及07年活螺密度分別為4.74、0.85及3.37只/0.1m~2,感染螺密度05年為0.0018只/0.1m~2,06及07年未壓出陽性螺,人群感染率分別為3.35%、1.59%及2.31%,耕牛感染率分別為12.31%、3.23%及3.03%。 第二部分運用遙感技術(shù)分析鄱陽湖區(qū)水面面積變化 本研究收集1998-2006年間的12景遙感影像,對其進行幾何校正,提取MNDWI值,并設(shè)定閾值,建立掩膜,然后劃定感興趣區(qū)求取鄱陽湖的水面面積。 對遙感影像中提取的鄱陽湖區(qū)的水域面積與星子、湖口及康山當(dāng)日的水位進行相關(guān)性分析,相關(guān)性均較強,相關(guān)系數(shù)分別為0.957、0.893及0.939,然后以鄱陽湖區(qū)水域面積與對應(yīng)的星子站當(dāng)日水位建立模型,其中對數(shù)模型的擬合效果較好,R=0.959,R~2=0.920,校正R~2=0.912,模型為S=5181.5111n(h)-10261.9,其中S:鄱陽湖區(qū)水域面積,h:獲取衛(wèi)片當(dāng)日星子水文站水位。利用2006年11月6日的TM遙感影像對鄱陽湖主體水域-水位模型進行驗證。結(jié)果表明,采用模型計算出的水域面積與遙感圖像測算的結(jié)果相差較小,運用影像提取的水域面積為1658.73km~2,用模型估算的水域面積為1648.20km~2,相差較小,誤差小于0.64%。說明運用遙感技術(shù)提取的水域面積可以較好地反映鄱陽湖區(qū)水位變化趨勢,從而為將遙感技術(shù)應(yīng)用于洲灘釘螺分布的預(yù)測提供了保證。 第三部分小范圍研究水位變化對螺情的影響 在血吸蟲病的傳播鏈中,水是必不可少的載體,且水與釘螺的孳生繁殖是密不可分的,水位的變化對于釘螺分布具有重要影響,有必要對水位變化對螺情的影響展開研究。 本研究先從小范圍上分析了水位變化對螺情狀況的影響,收集星子水文站1997-2007年的水位資料,以分析水位變化對渚溪試點區(qū)及星子縣釘螺分布狀況的影響。 經(jīng)相關(guān)統(tǒng)計分析發(fā)現(xiàn)渚溪試點區(qū)活螺框出現(xiàn)率與星子站上一年度8月份月平均水位間呈負(fù)相關(guān),相關(guān)系數(shù)r=-0.748,p=0.013＜0.05,此外渚溪試點區(qū)活螺框出現(xiàn)率還與上一年度豐水期平均水位及年最高水位間呈負(fù)相關(guān),結(jié)果分別為r=-0.652,p=0.041＜0.05及r=-0.771,p=0.009＜0.01。由此可推測豐水期水位越高,淹水時間越長,釘螺死亡率越高,活螺框出現(xiàn)率越低。 此外,星子縣湖沼型釘螺面積與星子站4月份月平均水位之間呈負(fù)相關(guān),結(jié)果為:r=-0.761,p=0.011＜0.05,說明洲灘初漲水期間提前漲水或水位升高,有螺面積減少。 第四部分大范圍上研究水位變化對有螺面積的影響 為了進一步驗證第二部分的結(jié)果,以星子站月平均水位代表鄱陽湖水位與江西省湖沼型釘螺面積之間進行相關(guān)性分析。結(jié)果發(fā)現(xiàn)江西省湖沼型釘螺面積與鄱陽湖4月份月平均水位呈負(fù)相關(guān),r=-0.658,p=0.039＜0.05,進一步說明四月份漲水越晚水位越低則釘螺面積越大。 本研究第二部分對遙感影像提取的水域面積與實際的水位信息之間進行了論證,而第三四部分的結(jié)果表明查螺前一年8月份的月平均水位及查螺當(dāng)年4月份的月平均水位高低影響著釘螺的分布及有螺面積,因此在實際應(yīng)用中可收集4月份及8月份的衛(wèi)片通過提取水域面積來預(yù)測釘螺分布及釘螺面積。
[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 .

【學(xué)位授予單位】：中國疾病預(yù)防控制中心
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2008
【分類號】：R184

【引證文獻】

相關(guān)期刊論文 前2條

1 羅靜偉;鄭博福;錢萬友;劉成林;戴年華;;基于生態(tài)安全的鄱陽湖濕地管理模式[J];安徽農(nóng)業(yè)科學(xué);2010年36期

2 蔡曉斌;陳曉玲;王學(xué)雷;甘文霞;;鄱陽湖水位空間差異及其對濕地水文分析的影響[J];華中師范大學(xué)學(xué)報(自然科學(xué)版);2011年01期

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本文編號：1697091