本文選題：三峽庫(kù)區(qū)　切入點(diǎn)：澎溪河回水區(qū)　出處：《西南大學(xué)》2015年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：在富營(yíng)養(yǎng)化問(wèn)題的研究與治理中,營(yíng)養(yǎng)鹽時(shí)空分布特征一直是富營(yíng)養(yǎng)化研究工作者關(guān)注和研究的對(duì)象,同時(shí)也是確立富營(yíng)養(yǎng)化水域治理措施的關(guān)鍵。三峽水庫(kù)蓄水之后導(dǎo)致干流水體倒灌支流形成了面積廣闊的回水區(qū),支流庫(kù)灣由原來(lái)的河流型轉(zhuǎn)變?yōu)楹葱浴榱朔篮榈男枰?三峽水庫(kù)采取高水位運(yùn)行(175m,11-第二年4月)、泄水期(5-6月中旬)、汛期低水位運(yùn)行(145m,6～8月)、蓄水期(9-11月)、高水位運(yùn)行的調(diào)度運(yùn)行方式。在調(diào)度運(yùn)行背景下,淹沒(méi)的大量農(nóng)田和消落帶既是營(yíng)養(yǎng)的匯,又是營(yíng)養(yǎng)的源,對(duì)水體營(yíng)養(yǎng)有補(bǔ)給作用。澎溪河作為三峽庫(kù)區(qū)消落區(qū)面積最大的支流,其營(yíng)養(yǎng)鹽受地表徑流輸入、干流倒灌、底泥和消落帶釋放等多種因素的影響。為探討三峽水庫(kù)調(diào)度運(yùn)行背景下,澎溪河回水區(qū)營(yíng)養(yǎng)鹽和葉綠素a時(shí)空變化及其相互關(guān)系,于2013年5月至2014年6月,在澎溪河高陽(yáng)平湖進(jìn)行了定點(diǎn)高頻監(jiān)測(cè),并開(kāi)展了兩次全流域調(diào)查。主要得到如下結(jié)論：(1)冬季高陽(yáng)平湖氮磷營(yíng)養(yǎng)鹽濃度最高,但是由于溫度低而沒(méi)有發(fā)生水華,水質(zhì)較好,處于中營(yíng)養(yǎng)水平。春末夏初(2014年4月-5月中旬)高陽(yáng)平湖水體富營(yíng)養(yǎng)化最嚴(yán)重,水體處于中度富營(yíng)養(yǎng)水平,5月10日甚至達(dá)到了重度富營(yíng)養(yǎng)化。水體富營(yíng)養(yǎng)狀態(tài)指數(shù)隨時(shí)間變化趨勢(shì)與葉綠素a的變化情況一致。營(yíng)養(yǎng)鹽濃度在不同水位條件下差異較大,NH4+-N在高水位期含量最小,在0.02 mg.L-1以下,水華期間最高,主要來(lái)源于水體內(nèi)部的氮循環(huán)；硝氮和總氮在2014年5月泄水期最高,高水位期次之,低水位期最低,干流倒灌輸入是高陽(yáng)平湖硝氮和溶解性磷的主要來(lái)源。高水位期,高陽(yáng)平湖硝氮和溶解性磷在總氮和總磷中所占比重分別為71.4%～95.4%和42.7%-94.4%,是高陽(yáng)平湖氮磷的主要組成部分,而降雨期間總磷的濃度高于高水位期,除干流倒灌外,降雨引起的地表徑流輸入是其另一個(gè)來(lái)源。(2)高陽(yáng)平湖水體分層受氣溫和水位變化的雙重影響。水體熱分層形成于春季(2014年3月2日-5月10日),從3月初開(kāi)始水溫出現(xiàn)水體弱分層現(xiàn)象,之后表底層溫差逐漸增大,4月下旬形成穩(wěn)定的分層結(jié)構(gòu)。5月下旬分層結(jié)構(gòu)被三峽水庫(kù)泄水引起的強(qiáng)擾動(dòng)破壞,溫躍層逐漸消失。混合層深度增加,從2014年5月10日的0.32m增加至29日的8.5m。仲夏水體分層最明顯,6月表底層溫差高達(dá)10.4℃。夏末(9月中旬),水體分層開(kāi)始逐漸消亡,冬季沒(méi)有分層。(3)水溫分層是影響高陽(yáng)平湖營(yíng)養(yǎng)鹽和葉綠素垂向分布的主要因素。水體沒(méi)有分層情況下,表、中、底層營(yíng)養(yǎng)鹽和葉綠素a無(wú)明顯差異,葉綠素a濃度小于3 μ,g.L-1。春季,隨著水溫分層的發(fā)生和發(fā)展,表層葉綠素a在69天內(nèi)從3μg.L-1驟增至183.73μg.L-1,并爆發(fā)水華。之后水體分層結(jié)構(gòu)被破壞,葉綠素a下降。營(yíng)養(yǎng)鹽垂向分布與水體的分層情況有關(guān),水體沒(méi)有分層情況下,各水層營(yíng)養(yǎng)鹽含量沒(méi)有明顯差異；水體分層以后,表、中、底層營(yíng)養(yǎng)鹽濃度差增大。(4)澎溪河大部分?jǐn)嗝嫠|(zhì)處于輕度富營(yíng)養(yǎng)水平,有個(gè)別斷面甚至達(dá)到重度富營(yíng)養(yǎng)。泄水前后水體富營(yíng)養(yǎng)化空間差異明顯,泄水初期上游斷面水質(zhì)較差,綜合營(yíng)養(yǎng)指數(shù)從下游到上游呈增大趨勢(shì)；泄水之后中下游斷面水質(zhì)較差,沿程綜合營(yíng)養(yǎng)指數(shù)變化趨勢(shì)呈拋物線型。水質(zhì)變化主要受藻類(lèi)水華影響,沿程水質(zhì)變化與葉綠素a濃度變化一致。(5)葉綠素a濃度的變化準(zhǔn)確反映了水華爆發(fā)的位置和嚴(yán)重程度,泄水初期,葉綠素a峰值出現(xiàn)在水華爆發(fā)最嚴(yán)重的斷面6和斷面7,泄水之后,其峰值出現(xiàn)在發(fā)生水華的斷面2和斷面4,隨著泄水過(guò)程中水位的下降,澎溪河水華爆發(fā)的區(qū)域有向下游遷移的趨勢(shì)。(6)總體來(lái)看無(wú)論泄水初期還是泄水后,三峽庫(kù)區(qū)長(zhǎng)江干流營(yíng)養(yǎng)鹽含量均高于澎溪河支流。澎溪河支流營(yíng)養(yǎng)鹽濃度從下游到上游呈下降趨勢(shì)。靠近河口斷面硝氮濃度大于2mg·L-1,上游斷面不到0.1mg·L-1,河口斷面溶解性總磷高達(dá)0.14mg·L-1,上游斷面低于0.06mg·L-1,干流輸入是澎溪河營(yíng)養(yǎng)鹽的主要來(lái)源。垂直方向上,4月靠近河口斷面的中層營(yíng)養(yǎng)鹽濃度最高,尤其是硝氮和溶解性總磷等可溶態(tài)營(yíng)養(yǎng)鹽,由此說(shuō)明干流水體從中層潛入澎溪河庫(kù)灣；7月主要表現(xiàn)為中下層濃度高于上層,說(shuō)明干流從中底層潛入。(7)澎溪河沉積物中高水位期檢出了41種磷脂脂肪酸,其中細(xì)菌有38種,放線菌2種,真菌1種；7月泄水之后總共檢出磷脂脂肪酸35種,其中細(xì)菌有32種,真菌和放線菌數(shù)量與泄水初期相同,總體上高水位和低水位條件下,澎溪河沉積物微生物種類(lèi)沒(méi)有顯著變化(P0.5),但是水位降低后磷脂脂肪酸的總含量除PX-2、PX-3、PX-7受流速和沉積物質(zhì)地影響較低外,其它斷面都明顯增加,同時(shí)各個(gè)斷面細(xì)菌的特征磷脂脂肪酸含量也普遍增加。高水位和低水位情況下,均是厭氧細(xì)菌占優(yōu)勢(shì),但是水位降低后好氧細(xì)菌豐度有一定的增加,說(shuō)明水位變化對(duì)微生物生物量和細(xì)菌結(jié)構(gòu)組成有影響。
[Abstract]:In the research and control of eutrophication in the temporal and spatial distribution of nutrition salt has been the object of eutrophication research workers concerned and researched, but also the key to establish the eutrophic water control measures. After the impoundment of Three Gorges Reservoir in river water from tributaries formed backwater area of the vast area, change from River tributaries bay the lake. In order to flood control needs, take the high water level of Three Gorges reservoir (175m 11-, April second), drainage period (5-6 month), the low water level operation in flood season (145m, 6~8), storage period (9-11 months), and operation mode of high water level operation. In the operation under the background, a lot of farmland flooded and riparian zone is not only the nutrient sink is the source of nutrition, replenishment effect on water nutrition. As the Pengxi River Three Gorges Reservoir area is the largest tributary, the nutrient input by surface runoff, dry Flow and sediment intrusion, eliminate the impact of various factors such as the fall release. To Three Gorges reservoir operation under the background of a, temporal and spatial variation of Pengxi River backwater area and the relationship between nutrients and chlorophyll, from May 2013 to June 2014, the fixed frequency monitoring in Pengxi River Gao Yang in Pinghu, and carried out two times the whole basin the investigation. The main conclusions are as follows: (1) the winter Gao Yang Pinghu nitrogen and phosphorus concentration is highest, but due to low temperature and no bloom, the water quality is good, in the nutritional level. In late spring and early summer (April 2014 -5 month) Gao Yang Pinghu the most serious water eutrophication eutrophication, water eutrophication level is moderate, even in May 10th reached the severe eutrophication. Changes consistent eutrophic state index with the trend of the temporal variation of a and chlorophyll. The nutrient concentration in different water level conditions, NH4 +-N in the high water level The content of the minimum period, below 0.02 mg.L-1, the highest nitrogen cycle in the bloom period, the main source of water; nitrate nitrogen and total nitrogen in May 2014 the highest discharge period, high water period, low water period is lowest, main stream reverse input is main source of Gaoyang Pinghu nitrate nitrogen and dissolved phosphorus. The high water level period Pinghu Gaoyang, nitrate nitrogen and dissolved phosphorus in total nitrogen and total phosphorus in the proportion was 71.4% ~ 95.4% and 42.7%-94.4%, is the main part of Pinghu Gaoyang nitrogen and phosphorus, and the concentration of phosphorus is higher than that of rainfall during the high water period, in addition to the main stream intrusion, surface runoff caused by the rainfall input is another source of. (2) the dual influence of Pinghu Gaoyang stratification by the temperature variation. The thermal stratification was formed in the spring (March 2, 2014 -5 10) from the beginning of March, the water temperature stratification is weak, after the surface and bottom temperature increase, the 4 month Ten form layered structure hierarchical structure of.5 in late August the Three Gorges reservoir water caused by strong disturbance, Wen Yueceng gradually disappear. The mixed layer depth increases, the most obvious increased from 0.32m in May 10, 2014 to 29 8.5m. summer water layer, 6 lunar bottom temperature difference reaches 10.4 degrees. At the end of the summer (mid September), stratified start gradually disappearing, winter is not stratified. (3) the water temperature stratification is the influence of Pinghu Gaoyang nutrients and chlorophyll vertical distribution. The main factors of water table, no delamination case, the underlying nutrient and chlorophyll a had no significant difference in chlorophyll a concentration less than 3 g.L-1., the spring, with the occurrence and development of water temperature stratification and the surface chlorophyll a in 69 days from 3 g.L-1 to 183.73 at g.L-1, and the outbreak of water bloom. After stratification structure was destroyed, chlorophyll a decreased. Nutrient vertical layers related to the distribution of water, water There is no hierarchical case, there is no significant difference in the water content of nutrient; water after stratification, table, and the underlying nutrient concentration difference increases. (4) the Pengxi River water quality in most mild eutrophic level, individual sections even to severe eutrophication. The difference before and after the water eutrophication was the initial discharge, upstream water quality is poor, the comprehensive nutrition index increases from downstream to upstream; discharge after the downstream water quality is poor, the comprehensive nutrition index trend of a parabola. The change of water quality is mainly affected by the algae bloom, along with variations of chlorophyll a concentration. The process of water quality variation of chlorophyll a (5) the concentration of algal blooms accurately reflect the location and severity, early discharge, chlorophyll a peak in the bloom of the worst outbreak of section 6 and section 7, after discharge, the peak appeared in the hair The 2 section students and section 4, with the decline of water level in the process of water, the outbreak of Pengxi River China region downstream migration trend. (6) the overall discharge or whether early discharge after nutrient contents were higher than that of the Yangtze River Three Gorges Reservoir of Pengxi River tributary. The Pengxi River tributary nutrient concentration from downstream to upstream declined. Near the estuary section of nitrate nitrogen concentration is greater than 2mg, L-1, 0.1mg, L-1 to the upstream cross section, the section dissolved total phosphorus reached 0.14mg - L-1, 0.06mg - L-1 lower than the upstream section, river input is the main source of Pengxi River nutrients. In vertical direction, close to April the middle section of estuarine nutrient concentration is highest, especially nitrate nitrogen and dissolved total phosphorus and soluble nutrients, the river water from the middle into the Pengxi River Bay; July is mainly in the lower concentration was higher, indicating that stem from the bottom flow Into the layer. (7) the Pengxi River Sediments in the high water level detection of 41 kinds of phospholipid fatty acids, of which there are 38 kinds of bacteria, actinomycetes and 2 species, 1 species of fungi; in July after a total discharge detection of phospholipid fatty acid 35, of which there are 32 kinds of bacteria, fungi and actinomycetes and early discharge the same, high water level and low water level conditions in general, there was no significant change in Pengxi River sediment microbial species (P0.5), but the content of total phospholipid fatty acid level decreased after the removal of PX-2, PX-3, PX-7 by flow velocity and sediment of the lower section, the other is significantly increased, while characteristics of phospholipid fatty acid content each section of bacteria are generally increasing. The high water level and low water level conditions are anaerobic bacteria dominant, but the water level decreased after aerobic bacterial abundance have increased, indicating the change of water level has an effect on microbial biomass and bacterial composition.

【學(xué)位授予單位】：西南大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：X524

【引證文獻(xiàn)】

相關(guān)期刊論文 前1條

1 周川;蔚建軍;付莉;崔玉潔;劉德富;姜偉;Douglas Haffner;張磊;;三峽庫(kù)區(qū)支流澎溪河水華高發(fā)期環(huán)境因子和浮游藻類(lèi)的時(shí)空特征及其關(guān)系[J];環(huán)境科學(xué);2016年03期

相關(guān)碩士學(xué)位論文 前1條

1 周川;三峽庫(kù)區(qū)支流澎溪河浮游生物生長(zhǎng)與水文、水質(zhì)的關(guān)系研究[D];西南大學(xué);2016年

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本文編號(hào)：1628226