【摘要】：長江中游干流魚類資源豐富,是產(chǎn)漂流性卵魚類的主要棲息和繁殖場所,以江湖洄游性魚類(青魚Mylopharyngodon piceus、草魚Ctenopharyngodon idellus、鰱Hypophthalmichthys molitrix和鳙Aristichthys nobilis)和定居性魚類(鯉Cyprinus carpio、魚即Carassius auratus等)為主。長江中游干流生態(tài)系統(tǒng)受到三峽大壩和葛洲壩建設(shè)、酷漁濫捕、江湖阻隔和水體污染等多重因素的疊加影響,漁業(yè)資源持續(xù)衰退,水生態(tài)系統(tǒng)服務(wù)功能趨于衰弱,本文通過在長江中游干流宜昌至湖口江段2011和2013～2014年所采集魚類和食物網(wǎng)中其它生物樣品,利用δ13C、δ15N穩(wěn)定性同位素技術(shù),研究了長江中游干流江段水生態(tài)系統(tǒng)中主要魚類營養(yǎng)級、食物網(wǎng)結(jié)構(gòu)及能量來源、懸浮顆粒有機(jī)物(POM)δ13C、δ15N穩(wěn)定性同位素特征和鰭條替代白色肌肉在青魚、鰱穩(wěn)定性同位素研究中的有效性,探討了長江中游干流生態(tài)系統(tǒng)魚類食物網(wǎng)及能量來源及其潛在影響,研究將有利于了解目前長江中游干流漁業(yè)生態(tài)系統(tǒng)狀況、漁業(yè)資源變化及其趨勢,能為漁業(yè)資源的可持續(xù)利用及其生態(tài)系統(tǒng)保護(hù)方面提供必要的基礎(chǔ)數(shù)據(jù)和技術(shù)支撐。主要研究結(jié)果如下：1.應(yīng)用穩(wěn)定性同位素技術(shù)(δ13C、δ15N)對2011年3月、9月,2013年7月、9月和12月采自長江中游干流宜昌、荊州、石首、監(jiān)利、城陵磯、鄂州、九江和湖口江段的44種魚類和3種水生無脊椎動物進(jìn)行了營養(yǎng)級研究。結(jié)果顯示,長江中游干流魚類的813C值范圍為-33.83‰(鳙)～17.36‰(南方鯰Silurus meridionalis),815N值范圍為4.83‰(泥鰍Misgurnus anguillicaudatus)～15.13‰(翹嘴湆Culter alburnus)。以梨形環(huán)棱螺(Bellamya purificata)的δ15N均值5.48%o作為營養(yǎng)級基準(zhǔn)線(營養(yǎng)級=2),計(jì)算出該江段水生動物的營養(yǎng)級處于2.42～4.88,主要集中在2.83～3.61之間,魚類平均營養(yǎng)級為3.28,營養(yǎng)級大于2.83的魚類種類數(shù)量占了總生物種數(shù)的80.85%,其食性競爭壓力較大,生態(tài)位重疊。大刺鰍(Mastacembelus armatus)和鳊Parabramis pekinensis)營養(yǎng)級最低,分別為2.42+0.49和2.56+0.52,營養(yǎng)層級大于4.0的高級消費(fèi)者為太湖新銀魚(Neosalanx taihuensis)、短頜鱭(Coilia brachygnathus)、鳙和長蛇泩(Saurogobio dumerili),分別為4.88+0.01、4.37±0.27、4.32±0.35和4.09±0.78,小黃黝魚(Micropercops swinhonis)、溼(Elopichthys bambusa)、鱖(Siniperca chuatsi)、翹嘴湆、青魚和南方鯰的營養(yǎng)級分別3.99、3.92±0.16、3.89±0.27、3.87+0.62、3.59±0.69和3.59+0.57。2.對2011年3月、9月,2013年7月、9月、12月和2014年3月采自長江中游干流宜昌、荊州、城陵磯、鄂州和湖口江段魚類、POM、底棲動物和水生植物等應(yīng)用碳氮穩(wěn)定性同位素技術(shù)構(gòu)建了這5個江段水生態(tài)系統(tǒng)在豐水期和枯水期食物網(wǎng)結(jié)構(gòu)。宜昌江段豐水期處于食物網(wǎng)頂端的魚類主要為銅魚(Coreius heterokon)、翹嘴湆和鳙,魚類營養(yǎng)級可分為3個層次,鯉、鳊和赤眼鱒等魚類在魚類食物網(wǎng)結(jié)構(gòu)中所處位置較低；在枯水期鳙和鱖的營養(yǎng)位置最高,鳊和鯉仍處于較低營養(yǎng)級位置。荊州江段豐水期處于高營養(yǎng)級位置的魚類為太湖新銀魚、短頜鱭、黃尾鲴(Xenocypris davidi)、烏鱧(Channa argus)和鱖,主要魚類營養(yǎng)層級有3個,中間層級魚類食性競爭壓力較大,在枯水期,短頜鱭、鳙、小黃黝魚、麥穗魚(Pseudorasbora parva)、圓尾斗魚Macropodus ocellatus)和翹嘴湆處于食物網(wǎng)高營養(yǎng)級位置。城陵磯江段豐水期食物網(wǎng)營養(yǎng)層級有4個,鱖、短頜鱭、南方鲇、溼和翹嘴湆處于魚類食物網(wǎng)高營養(yǎng)級位置,在枯水期,處于食物網(wǎng)較高營養(yǎng)層級的魚類為短頜鱭、溼和南方鲇。鄂州江段在豐水期魚類食物網(wǎng)中,翹嘴湆、南方鲇、青魚、溼和鱖營養(yǎng)層級最高,鳙、草魚和鳊營養(yǎng)級位置較低；在枯水期,食物網(wǎng)中營養(yǎng)級位置較高的為南方鲇、溼、烏鱧和青魚,餐(Hemicculter leuciclus)、草魚、鳊營養(yǎng)位置較低。湖口江段豐水期魚類食物網(wǎng)可分為4個層級,翹嘴湆、短頜鱭、長蛇泩、南方鲇、鱖和青魚處于較高營養(yǎng)層級,鰱、鳊、草魚和(?)處于較低營養(yǎng)級位置；在枯水期,翹嘴湆、花(?)Hemibarbus maculatus)和唇(?)(Hemibarbus labeo)營養(yǎng)級位置較高,鰱、草魚、鳙(?)在食物網(wǎng)中處于較低營養(yǎng)層級。在長江中游江水流向梯度上,長江中游干流宜昌至湖口江段主要魚類的δ13C值隨江水流向有總體降低趨勢,魚類的δ15N值變化不大。3.結(jié)合IsoSource模型,利用穩(wěn)定性同位素技術(shù)研究和探討了三峽大壩建成蓄水后長江中游干流宜昌至湖口江段9種主要經(jīng)濟(jì)魚類(草魚、鰱、鯉、鳊、南方鲇、鱖、鯽、黃顙魚(Pelteobagrus fulvidraco)和翹嘴湆)的能量來源及其所受影響。草魚、鰱和鯉等9種主要經(jīng)濟(jì)魚類的813C、δ15N值范圍分別為-29.25±3.22(鰱)～-24.26±2.8(鳊)、8.42±1.9(鯉)～11.67±0.9(鱖)。魚類的C/N比值范圍處于3.26+0.12(鰱)～4.23±0.9(黃顙魚),除鯽和黃顙魚外,其余7種主要經(jīng)濟(jì)魚類的C/N比值都較為接近。通過IsoSources模型計(jì)算了長江中游干流江段4種潛在碳源(懸浮顆粒有機(jī)物(POM)、固著藻類、C3植物和C4植物)對這9種主要經(jīng)濟(jì)魚類能量貢獻(xiàn)的頻率,發(fā)現(xiàn)其能量來源以POM和C3植物為主。4.為了解三峽水庫蓄水后長江中游干流江段魚類食物網(wǎng)主要能源之一的POM時空變化特征及組成來源,于2013年7月至2014年3月,對長江中游干流宜昌、石首、城陵磯、鄂州和九江江段懸浮顆粒有機(jī)物的碳穩(wěn)定性同位素(δ13 CPOM)和氮穩(wěn)定性同位素(δ15NPOM)進(jìn)行了研究。結(jié)果顯示,長江中游干流江段δ13CPOM值變化介于-25.21‰～-19.12%o,δ15NPOM值變化介于2.58%o～8.78‰,C/N平均值變化介于6.99～15.5,δ13CPOM在7月份最高,在3月和12月較低,這可能主要與7月份洪汛期降雨導(dǎo)致大量外源有機(jī)物流入而引起的POM組成變化有關(guān)。通過方差分析發(fā)現(xiàn)δCPOM在3月和12月沒有顯著性差異,其余月份間均存在顯著性差異(p0.001),各采樣點(diǎn)之間沒有顯著性差異。δ15NPOM在7月和9月有顯著性差異(p0.001),其余月份間均不存在顯著性差異,各采樣點(diǎn)之間城陵磯和九江江段有顯著性差異(p0.001),其余各采樣點(diǎn)之間沒有顯著性差異。運(yùn)用二元混合模型計(jì)算結(jié)果顯示,長江中游干流江段POM組成以陸源有機(jī)質(zhì)為主,平均貢獻(xiàn)率為72.8%并存在明顯的季節(jié)性變化,陸源有機(jī)質(zhì)所占的比例在7月洪汛期高(81%～92%),3月和12月枯水期低(20%～53%),同長江徑流量關(guān)系較為密切。三峽水庫和長江上游眾多水庫群的蓄水及削減洪峰的調(diào)度方式、長江中游干流江段大規(guī)模的河道護(hù)坡活動,導(dǎo)致河源物質(zhì)、洪泛區(qū)域物質(zhì)和濱岸帶植被等外源性碳源輸入受到較大影響,長江中游干流江段可能會逐漸失去作為大型洪泛河流生態(tài)系統(tǒng)典型的能量循環(huán)和流動模式。5.穩(wěn)定性同位素分析技術(shù)已廣泛應(yīng)用于水生態(tài)系統(tǒng)中營養(yǎng)關(guān)系和能量流動研究,在魚類方面,通常是將其處死后取背部白色肌肉用于樣品分析,因此使用非致命性采樣替代其肌肉組織用于同位素分析研究正愈發(fā)受到關(guān)注和嘗試。目前國內(nèi)還未見使用魚類鰭條替代肌肉用于相關(guān)研究的報道。本研究比較了青魚、鰱鰭條與肌肉組織中δ13C和δ15N比值,青魚的鰭條δ13C比值比肌肉平均高0.44‰,615N比值比肌肉平均高0.09‰。鰱的鰭條813C比值比肌肉平均高0.22‰,δ15N比值比肌肉平均高0.66‰。對青魚、鰱的鰭條與肌肉組織δ13C和δ15N比值構(gòu)建線性模型發(fā)現(xiàn),青魚、鰱的鰭條與肌肉組織δ13C和δ15N比值存在顯著性相關(guān)(R20.9,p0.001)�？刹捎梅侵旅蓸拥啮挆l組織替代其白肌肉應(yīng)用穩(wěn)定性同位素技術(shù)研究青魚、鰱在食物網(wǎng)中的營養(yǎng)級位置。
[Abstract]:The main stream of the middle reaches of the Yangtze River is rich in fish resources. It is the main habitat and breeding place for drifting egg-laying fish. The migratory fish (Mylopharyngodon piceus, Ctenopharyngodon idellus, Hypophthalmichys molitrix and Aristichthys nobilis) and the settled fish (Cycarpcarpius, Carassauratus, etc.) The main stream ecosystem of the middle reaches of the Yangtze River is affected by the construction of the Three Gorges Dam and Gezhouba Dam, excessive fishing, barrier between rivers and lakes and water pollution. Fishery resources continue to decline, and aquatic ecosystem service function tends to weaken. By using stable isotope techniques of delta 13C and delta 15N, the nutrient levels, food web structure and energy sources of main fishes, stable isotope characteristics of suspended particulate organic matter (POM) Delta 13C, Delta 15N and fin substitution for white muscle in the aquatic ecosystem of the middle reaches of the Yangtze River were studied. The validity of the study was discussed. The fish food web, energy sources and their potential impacts in the mainstream ecosystem of the middle reaches of the Yangtze River were discussed. The study will be helpful to understand the current status of the fishery ecosystem, the changes and trends of fishery resources in the mainstream ecosystem of the middle reaches of the Yangtze River. The main results are as follows: 1. The nutrient levels of 44 species of fish and 3 species of aquatic invertebrates collected from Yichang, Jingzhou, Shishou, Jianli, Chenglingji, Ezhou, Jiujiang and Hukou sections of the middle reaches of the Yangtze River in March, September, July, September and December 2011 were studied by using stable isotope technique (delta 13C, Delta 15N). The results showed that 813C values of fish in the middle reaches of the Yangtze River ranged from - 33.83 (bighead) to 17.36 (Silurus meridionalis), and 815N values ranged from 4.83 (Misgurnus anguillicaudatus) to 15.13 (Culter alburnus). The mean value of delta N of Bellamya purificata was 5.48% as the baseline line of Trophic Grade (Ying). The nutrient level of aquatic animals in this reach is 2.42-4.88, mainly between 2.83-3.61, the average nutrient level of fish is 3.28, and the number of fish species whose nutrient level is greater than 2.83 accounts for 80.85% of the total number of species. The competition pressure of feeding habits is high, and the niche overlaps. Innsis had the lowest nutrient levels, which were 2.42+0.49 and 2.56+0.52, respectively. The top consumers with nutrient levels greater than 4.0 were Neosalanx taihuensis, Coilia brachygnathus, bighead carp and Saurogobio dumerili, which were 4.88+0.01, 4.37+0.27, 4.32+0.35 and 4.09+0.78, respectively. The nutrient levels of Elopichthys bambusa, Siniperca chuatsi, Snakehead, Qingyu and Southern Catfish were 3.99, 3.92+0.16, 3.89+0.27, 3.87+0.62, 3.59+0.69 and 3.59+0.57.2 respectively. The structure of food webs in the five sections of the river was constructed by carbon and nitrogen stable isotope techniques. The fish at the top of the food webs were mainly Coreius heterokon, Coreius heterokon and bighead carp in the wet season of Yichang River. The nutrient levels of fish could be divided into three levels: carp, gill and red-eyed trout. The fish in the high trophic position in the Jingzhou reach are the new whitebait of Taihu Lake, the short jawed fish, the yellow tail fish (Xenocypris davidi), the black snake (Channa argus) and the Mandarin fish. The main fish in the high trophic position are the new whitebait, the short jawed fish, the yellow tail fish (Xenocypris davidi), the black snake (Channa argus) and the Mandarin fish. In the dry season, there are 4 nutritional levels in the food web of Chenglingji River during the flood season, and there are 4 nutritional levels in the food web of Chenglingji River, such as Siniperca chuatsi, bighead carp, Pseudorasbora parva, Macropodus ocellatus and Cocklehead bream. In the dry season, the fish in the higher trophic level of the food web are short-jawed squid, wet and southern catfish. The nutrient position of the fish food web in the lake estuary during the flood season can be divided into four levels: warped-billed scorpion, short-jawed squid, long snake locust, southern catfish, mandarin fish and herring fish in the higher trophic level, silver carp, silver carp, grass carp and (?) in the lower trophic level; in the dry season, warped-billed scorpion, snake bream and (?) in the lower trophic level. Hemibarbus maculatus and Hemibarbus labeo had higher trophic levels and silver carp, grass carp and bighead carp were in lower trophic levels in the food web. 3. Based on IsoSource model, the energy sources of 9 main economic fishes (grass carp, silver carp, carp, slave, southern catfish, Mandarin fish, crucian carp, yellow catfish (Pelteobagrus fulvidraco) and their impacts on the middle reaches of the Yangtze River from Yichang to Hukou after the impoundment of the Three Gorges Dam are studied and discussed by using stable isotope technique. The values of 813C and delta 15N of the main economic fishes were - 29.25 (- 3.22) (silver carp) ~ - 24.26 (- 2.8) (gill) and 8.42 (- 1.9) (carp) ~ 11.67 (- 0.9) (mandarin fish). The C/N ratios of the main economic fishes were in the range of 3.26 + 0.12 (silver carp) ~ 4.23 (- 0.9) (yellow catfish). Except crucian carp and yellow catfish, the C/N ratios of the other seven main economic fishes were close to Isource model. Frequencies of energy contribution of four potential carbon sources (suspended particulate organic matter (POM), fixed algae, C3 and C4 plants) to the 9 main economic fishes in the middle reaches of the Yangtze River were found to be mainly from POM and C3 plants. 4. To understand POM space-time of one of the main energy sources of fish food web in the middle reaches of the Yangtze River after the impoundment of the Three Gorges Reservoir. From July 2013 to March 2014, carbon stable isotopes (delta 13 CPOM) and nitrogen stable isotopes (delta 15 NPOM) of suspended particulate organic matter (SOM) in Yichang, Shishou, Chenglingji, Ezhou and Jiujiang sections of the middle reaches of the Yangtze River were studied. The results show that the variation of delta 13 CPOM values in the middle reaches of the Yangtze River is between - 25.21. -19.12% o, 65 There was no significant difference between the other months (p0.001). There was no significant difference between the sampling sites. There was no significant difference between July and September (p0.001). There was no significant difference between the other months. There was significant difference between the sampling sites in Chenglingji and Jiujiang (p0.001). There was no significant difference among the other sampling sites. The results of the binary mixed model show that the POM composition in the middle reaches of the Yangtze River is dominated by terrestrial organic matter with an average contribution rate of 72.8% and obvious seasonal variation. The proportion of terrestrial organic matter is higher in July flood season (81%-92%) and lower in March and December dry season (20%-53%). It is closely related to the runoff of the Yangtze River. The impoundment of the Three Gorges Reservoir and the regulation of flood peak reduction in many reservoirs in the upper reaches of the Yangtze River and the large-scale river slope protection activities in the middle reaches of the Yangtze River have greatly affected the import of exogenous carbon sources such as river source materials, flooding area materials and coastal vegetation. The middle reaches of the Yangtze River may gradually lose their role as large-scale flooding. Typical energy cycle and flow patterns in river ecosystems. 5. Stable isotope analysis techniques have been widely used in the study of nutrient relationships and energy flow in aquatic ecosystems. In fish, white muscles in the back are usually taken after execution for sample analysis, so non-lethal sampling is used instead of muscle tissue for the same purpose. The study compares the ratios of delta 13C to delta 15N in muscle tissues, the ratios of delta 13C to delta 15N in fins of herring, silver carp and silver carp, and the ratios of delta 13C to delta 15N in fins of herring are 0.44 higher than that of muscle and 0.09 higher than that of muscle. The ratio of 813C to muscle was 0.22, and the ratio of delta 15N to muscle was 0.66. For herring, the linear model of the ratio of fin to muscle tissue showed that there was a significant correlation between the ratio of delta 13C to delta 15N in muscle tissue and the ratio of fin to muscle tissue in herring and silver carp (R20.9, p0.001). The stable isotope technique was used to study the trophic level of black carp and silver carp in food web.
【學(xué)位授予單位】：西南大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：S931.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 劉紹平;陳大慶;段辛斌;邱順林;黃木桂;;長江中上游四大家魚資源監(jiān)測與漁業(yè)管理[J];長江流域資源與環(huán)境;2004年02期

2 曹文宣;;有關(guān)長江流域魚類資源保護(hù)的幾個問題[J];長江流域資源與環(huán)境;2008年02期

3 陳大慶，邱順林，黃木桂，劉紹平;長江漁業(yè)資源動態(tài)監(jiān)測的研究[J];長江流域資源與環(huán)境;1995年04期

4 魏秀國;沈承德;孫彥敏;易惟熙;;珠江水體懸浮物碳穩(wěn)定同位素組成與流域土壤侵蝕研究[J];沉積學(xué)報;2008年01期

5 蔡德陵,李紅燕,周衛(wèi)建,劉衛(wèi)國,曹蘊(yùn)寧;無定河流域碳氮穩(wěn)定同位素研究[J];地球化學(xué);2004年06期

6 柯福恩，，危起偉，羅俊德，楊文華;三峽工程對長江漁業(yè)資源的影響與補(bǔ)救措施[J];淡水漁業(yè);1994年01期

7 徐軍;張敏;謝平;;氮穩(wěn)定同位素基準(zhǔn)的可變性及對營養(yǎng)級評價的影響[J];湖泊科學(xué);2010年01期

8 林琳;吳敬祿;曾海鰲;劉文;;人類活動對太湖水環(huán)境影響的穩(wěn)定氮同位素示蹤[J];湖泊科學(xué);2012年04期

9 范振華;巴家文;段辛斌;;長江宜昌至城陵磯江段魚類資源現(xiàn)狀及物種多樣性研究[J];淡水漁業(yè);2012年04期

10 霍堂斌;姜作發(fā);馬波;李U

本文編號：2240977