张永领
, 董玉龙
ZHANG Yong-ling, DONG Yu-long
中图分类号: X144
文献标识码: A
文章编号: 1000-0690(2015)07-0912-07
收稿日期: 2014-10-2
修回日期: 2015-02-8
网络出版日期: 2015-07-20
版权声明: 2015 《地理科学》编辑部 本文是开放获取期刊文献，在以下情况下可以自由使用：学术研究、学术交流、科研教学等，但不允许用于商业目的.
基金资助:
作者简介:
作者简介：张永领（1975-）,男,山东成武人,博士,副教授,主要从事河流碳循环、灾害应急研究。E-mail:zhyongling@126.com
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摘要
通在黄河三门峡水文站进行1 a的连续采样分析和调水调沙期间的密集采样分析,揭示了三门峡水库水沙调控对黄河有机碳输送过程的影响。结果表明,在水库调水调沙期间,三门峡站POC含量与TSS含量同步增加,而DOC含量变化趋势不明显;在1 a内,DOC和POC含量均有明显的季节变化。三门峡站POC年通量为124.8万t,其中调水调沙期间POC输送量约占POC年通量的38%,水库敞泄期间（8~9月）的POC输送量约占POC年通量的60%;三门峡站DOC年通量为7.6万t,其中7~9月DOC输送量约占DOC年通量的52%。
关键词：
Abstract
The Sanmenxia Reservoir, controlling 89% of the water and nearly 100% of the sediment, is an important hydro-junction in the middle reaches of the Huanghe River. By sampling within a complete hydrologic year at the Sanmenxia Station and intensive investigation during water-sediment regulation period, combining with the hydrological data over the same period, impacts of the Sanmenxia Reservoir on organic carbon transport processes was revealed by the operation mode. Water storage, sediment interception (water and sediment regulation), and open discharge were well studied. Results indicated that the particulate organic carbon (POC) rise simultaneously with the sharp increasing of total suspended particle (TSS) contents, whereas the dissolved organic carbon (DOC) content showed no significant change during the water-sediment regulation of the Sanmenxia Reservoir. Over the whole year, DOC content implied significant seasonal change, which was higher in January-February and July-September, lower in other months; POC content showed higher from July-September but lower in the other months. At the Sanmenxia Station, annual POC flux was 1.248 million t, of which POC transport in July accounted for about 38% of the total, and POC during August-September occupied 60% of the total. Annual DOC flux was 76,000 t, the part during July-September was 52% of the annual total. Under the influence of the reservoir, organic carbon transport was dominated by POC during the flood season, while mainly controlled by DOC during the dry season. On the whole year, the organic carbon transport was firstly affected by POC, which was about 16.5 times of DOC. Influence of Sanmenxia Reservoir on organic carbon transport in the Huanghe River was significantly different from other reservoirs, by not only intercepting POC in the dry season, but also discharging a large number of intercepted POC during the flood season. Moreover, organic carbon could transports directly from the upstream to the downstream during discharge period from August to September
Keywords：
河流系统是连接陆地和海洋两大碳库的重要纽带,是将陆地侵蚀的含碳物质输送到海洋的主要通道,这种由陆地向海洋的碳运输构成了全球碳循环的一个重要环节[1]。早在1974年E. T. Degens就开始了河流碳的生物地球化学循环研究。近年来随着全球变暖受到普遍重视[2~4],碳的循环问题也随之又成为研究的热点[5,6],而作为全球碳循环重要组成部分的河流碳循环也随之受到关注[7,8]。尤其是人类活动对流域地表的干扰程度加剧以及生产、生活中大量废弃物质的随意排放,使河流碳在通量上和性质上已经发生并且正在发生剧烈变化[9,10]。人类活动对流域地表的改变主要体现在土地利用方式的变化上,如森林草原植被的破坏[11~13]、工程设施的修建[14,15]、农业耕作方式的改变[16]、城市化[12,17]等过程,都记录在河流碳的性质和通量的变化上。人类修筑的大型水库或拦河坝直接改变了自然状态下的河流水文、水力过程,进而改变了河流悬浮物的“输移-沉积”模式和河流碳的生物地球化学过程[18,19]。
黄河是世界上泥沙含量最高的河流,在过去50 a里黄河径流量和输沙量已经大大降低,大量泥沙滞留在水库和河道里[20,21]。为将沉积在河流系统的泥沙输送到海洋,从2002年起黄河水利委员会通过联合调度黄河干流的几个大型水库如小浪底水库、三门峡水库和万家寨水库进行调水调沙,这个过程必然对黄河有机碳通量及输送过程产生深远的影响。自20世纪80年代以来,黄河河流碳循环逐渐受到研究者的关注[22~27]。目前黄河水沙调控已经深刻改变了有机碳的输送规律,而我们对大型水库水沙调控影响下的有机碳输送规律仍缺乏全面的认识,因此亟待深入研究参与黄河“调水调沙”的大型水库对有机碳的输送过程产生的影响,揭示在大型水库的影响下黄河有机碳的输运特征。
随着黄河流域降水量的减少以及工农业用水增加等原因,黄河水沙输送量明显减小,淤积日益严重[20,21,28]。为了能将淤积在水库和河床的泥沙输送到海洋,从2002年起通过联合调度黄河中游的万家寨、三门峡和小浪底3座大型骨干水库进行调水调沙,将沉积在水库里和河床上的泥沙送入大海,从而减少库区和河床的淤积。
为了研究黄河调水调沙的骨干水库——三门峡水库对有机碳输送的影响,于2011年11月至2012年10月在三门峡水文站进行每月1次的周期性采样,并于2012年7月3~8日在三门峡水库调水调沙期间进行每天1~2次的采样。采样地点位于三门峡水文站采样断面中间,用Niskin采水器采取水样,采样深度为水面以下1 m。
盛装水样的容器分为两类,一是经过高温（450℃）灼烧的棕色石英玻璃瓶（2 L）,在装样品之前先用水样洗涮棕色玻璃瓶3次,装样后滴加适量的饱和HgCl2溶液;二是用20 L的聚乙烯塑料桶装样,在装样之前,首先用水样洗涮塑料桶3次,装满样品后滴加适量的饱和HgCl2溶液。对于用棕色玻璃瓶盛装的样品（2 L）,用直径为47 mm的Whatman GF/F型玻璃纤维质滤膜（孔径0.7 μm）过滤水样,过滤后将滤液盛装在50 mL的棕色玻璃瓶中用于测试DOC,滤膜在-20℃恒温保存用于测试POC。对于用聚乙烯塑料桶盛装的样品（20 L）,用直径150 mm的聚碳酸酯纤维滤膜（孔径0.45 μm）过滤,滤出的颗粒物在50℃下烘干后测定TSS。用美国Tekmar Dohrmann公司生产的Apollo 9000 TOC/TN测定仪测试DOC和POC含量。2011~2012年黄河三门峡水文站水文资料来自黄河水利委员会水文局。
2012年6月18日至7月8日黄河进行调水调沙,为配合这次调水调沙,三门峡水库于2012年7月4~8日进行调水调沙。图1给出了2012年三门峡水库调水调沙期间三门峡站河水流量的变化趋势。在三门峡水库调水调沙期间,三门峡站溶解有机炭（DOC）含量为1.56~2.21 mg/L（图2）,其中7月4日8时DOC含量最高,主要是因为7月4日早晨三门峡地区经历了一次强降水过程,降水将地表大量溶解有机碳输送到了河流系统,从而增加了河水DOC含量。
河流总悬浮质（TSS）是POC的载体,TSS含量越多对POC的输送能力就越强。三门峡水库于7月4日加大下泄流量,7月5日8时水库开始大量排沙,到了14~20时三门峡站河流TSS含量持续在200 g/L左右,20时以后,河流TSS含量开始逐渐降低。随着三门峡水文站TSS含量的变化,悬浮颗粒物中有机碳的含量（POC的百分含量）也发生明显变化（图3）。在调水调沙的前期TSS含量小,POC的百分含量较高;随着河流TSS含量的增加,POC的百分含量逐渐降低并趋于稳定,主要是因为在调水调沙前期河流悬浮颗粒物以细颗粒物质为主,其有机碳含量相对较高[26],随着水库开始排沙,大量颗粒物较粗的泥沙进入水体从而使POC的百分含量降低。
图1 2012年三门峡水库调水调沙期间三门峡站河水流量
Fig.1 Runoff of Sanmenxia Station during the water-sediment regulation of Sanmenxia Reservoir in 2012
图2 2012年三门峡水库调水调沙期间三门峡站DOC含量
Fig.2 DOC content of Sanmenxia Station during the water-sediment regulation of Sanmenxia Reservoir in 2012
图3 2012年三门峡水库调水调沙期间三门峡站POC的百分含量和POC含量
Fig.3 The POC content and its percent to the total organic carbon in Sanmenxia Station during the water-sediment regulation of Sanmenxia Reservoir in 2012
在三门峡水库调水调沙期间三门峡站POC含量为0.92~507.68 mg/L（图3）。在调水调沙前期的排水阶段,POC含量为0.92~5.85 mg/L;在后期的排沙阶段,随着河流TSS含量急剧增加,POC含量也随之急剧增加,最高达到507.68 mg/L。对TSS和POC含量进行相关分析表明,两者表现出显著的正相关关系（P<0.05）。
1） DOC含量的季节变化。2011年11月至2012年10月三门峡站DOC含量介于1.73~2.75 mg/L之间,平均为2.10 mg/L,并有明显的季节变化（图4）。冬季的1~2月和夏季的8~9月DOC含量较高,其它月份DOC含量较低。黄河三门峡站DOC含量季节性变化与黄河径流量的变化、三门峡水库运行模式等因素有关。11月以后黄河内蒙古河段开始结冰,上游来水量逐渐减少,这时黄河中游地区汇入河流系统的大量的生产和生活污水[29]因为上游来水量少得不到有效稀释,可能是造成了1~2月DOC含量偏高的主要原因。3~6月黄河流域降水量偏小,三门峡水库以蓄水下泄为主,且下泄流量比较小,这个时段DOC含量变化不大。8~9月三门峡水库处于敞泄状态,上游来水经过三门峡水库后直接流向下游。由于黄河流域8~9月气温高且降水相对丰沛,有利于植被的生长以及降水对地表有机质的侵蚀输出,所以8~9月DOC含量明显高于春秋季。
图4 2011年11月至2012年10月三门峡站DOC含量
Fig.4 DOC content in Sanmenxia Station from November 2011 to October 2012
2） POC含量的季节变化。为客观反映三门峡站POC含量的季节变化特征,综合考虑2012年7月4~8日三门峡水库调水调沙期间的POC数据。2011年11月至2012年10月三门峡站POC的百分含量在0.35%~1.32%之间（图5）,并且有明显的季节性波动。2011年12月至2012年2月因黄河上游部分河段封冻,上游的来水量减少对排入黄河的污水的稀释作用减弱,导致POC的百分含量较高。3月和7~10月POC的百分含量较低,主要是因为这几个月河流泥沙含量较高导致了POC的百分含量偏低。
三门峡站汛期的POC的百分含量与黄河花园口站POC的百分含量[26]和黄河利津站POC的百分含量[27]相一致,这也表明黄河中下游的河流TSS主要来自黄土高原的黄土母质。
2011年11月至2012年10月三门峡站POC含量介于0.32~118.27 mg/L之间（表1）,平均为19.57 mg/L。三门峡站POC含量有明显的季节性变化,枯水期POC含量较低,汛期POC含量较高,其中7月POC含量最高,为118.27 mg/L,主要是因为7月初三门峡水库通过调水调沙向下游输送大量的悬浮颗粒物,大大增加了河流POC含量;8~9月水库处于敞泄状态,TSS含量比较高的河水通过三门峡水库直接流向下游,所以8~9月三门峡站POC含量也较高。
对POC含量和流量进行相关分析表明两者相关性不强（p>0.05）,其原因可能与黄河水沙异源有关,同时也与水库调水调沙有关。图6给出了三门峡水文站POC含量和TSS之间的关系,从图可知,POC含量随着TSS含量的增加而同步增加,对POC含量和TSS含量进行相关分析,p<0.01,表明两者具有非常显著的正相关关系。
Ran等对黄河利津站的POC含量进行研究表明[27],在调水调沙期间利津站平均POC含量明显低于三门峡站调水调沙期间的平均POC含量;在枯水期的1~5月,利津站POC含量明显高于三门峡站同期的POC含量;而在汛期的8~9月利津站POC含量又明显低于三门峡站同期的POC含量。三门峡站和利津站POC的差异与三门峡水库的影响有关,在枯水期三门峡水库大量拦截泥沙而下泄TSS含量比较低的清水,所以在枯水期三门峡站POC含量较低;利津站位于黄河入海口处,枯水期从小浪底水库排出的TSS含量比较低的河水在向利津站流动的过程中,通过冲刷作用使大量河流沉积物进入水体,从而增加了利津站的POC含量。在黄河调水调沙期间,大量泥沙在短时间内被排出水库,使三门峡站POC含量较高;而利津站POC含量较低是因为在调水调沙期间大量泥沙沉积在河底而降低了利津站的POC含量。8~9月三门峡水库处于敞泄状态,高含TSS的河水通过三门峡水库向下流动的过程中部分沉积在河道中或者被下游的小浪底水库截留,这就导致了8~9月利津站POC含量明显低于三门峡站。
表1 黄河三门峡站的POC含量
Table 1 POC content of Sanmenxia Station in Yellow River
| 采样时间（月） | 2011年 | 2012年 | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 11 | 12 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
| POC（mg/L） | 0.42 | 0.38 | 0.55 | 0.69 | 1.85 | 0.36 | 0.32 | 0.48 | 118.27 | 55.63 | 50.86 | 4.98 |
图6 三门峡站POC含量和TSS之间的关系
Fig.6 Relationship between POC and TSS in Sanmenxia Hydrological Station
对于DOC通量的计算采用分别计算每个月的DOC通量,然后再计算全年DOC通量方法：
式中,FDOC表示DOC年通量,
TSS是POC的载体,TSS输送量决定了POC通量,因此在估算河流POC通量时通常根据POC与TSS之间的关系建立POC通量计算公式[30]。三门峡站POC和TSS之间有如下关系：
CPOC=3.359 9CTSS+1.037 7, R2=0.979 7, n=21 （2）
式中,CPOC表示POC含量,CTSS表示TSS含量。
三门峡站POC年通量采用下列公式计算：
式中,FPOC表示POC年通量,
式中
根据上述公式分别计算出了三门峡站DOC和POC通量,计算结果列于表2。
表2 三门峡水文站DOC和POC通量（t）
Table 2 DOC and POC flux in Sanmenxia Hydrological Station (t)
| 时间（年-月） | FDOC | FPOC | FDOC/FPOC |
|---|---|---|---|
| 2011-11 | 4437.96 | 1002.64 | 4.43 |
| 2011-12 | 4960.81 | 889.55 | 5.58 |
| 2012-1 | 3384.84 | 544.87 | 6.21 |
| 2012-2 | 4108.45 | 731.74 | 5.61 |
| 2012-3 | 4765.78 | 4518.99 | 1.05 |
| 2012-4 | 3032.12 | 433.33 | 6.99 |
| 2012-5 | 1948.51 | 333.41 | 5.84 |
| 2012-6 | 3382.72 | 923.17 | 3.66 |
| 2012-7 | 7999.32 | 478046.19 | 0.02 |
| 2012-8 | 14307.19 | 358894.89 | 0.04 |
| 2012-9 | 16983.56 | 385803.65 | 0.04 |
| 2012-10 | 6310.26 | 15872.73 | 0.40 |
| 全 年 | 75621.52 | 1247995.16 | 0.062 |
2011年11月至2012年10月三门峡站DOC通量为7.56万t,其中9月DOC通量最多,占全年DOC通量的22.46%;其次是8月,DOC通量占全年DOC通量的18.92%;而在三门峡水库调水调沙的7月,DOC通量仅占全年DOC通量的10.58%。
2011年11月至2012年10月三门峡站POC通量为124.8万t,其中7月最多,占全年POC通量的38.30%,9月和8月次之,POC通量分别占全年POC通量的30.91%和28.76%;7~9月完成了全年POC输送量的97.98%。
在黄河开始进行调水调沙之后（2002年以后）,Ran等[27]、Zhang等[26]和Wang等[31]估算黄河DOC年入海通量分别为6、3.2和3.2万t,明显低于三门峡水文站的7.65万t;估算的POC年入海通量分别为41、39和38.9万t,也明显低于三门峡水文站的124.8万t。三门峡站DOC和POC通量明显高于入海通量的主要原因可能是,一方面水沙从三门峡站向下输送的过程中大量泥沙出现了沉积,另一方面是由于黄河下游的工业用水和农业灌溉用水造成了黄河入海流量减小,所以使POC和DOC的输送量减小。
在黄河进行调水调沙之前（在2002年之前）,Gan等[32]、Cauwet等[23]、Zhang等[22]分别估算黄河全年DOC通量分别为54、6和20万t;POC年通量分别为35、450和610万t,这和本研究结果以及Ran等[27]、Zhang等[26]和Wang等[31]估算的DOC和POC通量有较大差异,这可能与流量、泥沙含量以及采样时间、采样地点等因素有关。
三门峡站DOC和POC的通量之比有明显的季节性变化, 2011年11月至2012年6月,FDOC/FPOC大于1（表2）,说明三门峡站有机碳的输送以DOC为主。在枯水期三门峡水库拦蓄上游来的泥沙,下泄TSS含量非常低的清水,所以在枯水期三门峡站有机碳的输送以DOC为主,其中在1和4月DOC的输送量是POC的6倍以上。
2012年7~10月DOC和POC的通量之比小于1（表2）,说明这4个月三门峡站有机碳的输送以POC为主,其中7月FDOC/FPOC的值最小,仅为0.02;8月和9月次之,FDOC/FPOC的值均为0.04,主要是因为7月三门峡水库通过调水调沙将大量泥沙排出水库,8~9月三门峡水库处于敞泄状态,从黄河中游来的泥沙通过三门峡水库直接流向下游,所以这一时段POC的输送占绝对优势。从全年来看,三门峡站POC输送量远远超过DOC输送量,FDOC/FPOC为0.062,表明黄河三门峡站河流有机碳的输送以POC为主。Cauwet等[23]、Zhang等[22]、Ran等[27]、Zhang等[26]和Wang等[31]分别得出的黄河DOC和POC的输送通量比例为0.013、0.032、0.146、0.082和0.082,和本研究结果比较接近。
目前黄河中上游地区建有大、中、小型水库3 000多座,这些水库不仅大大改变了黄河水沙输送规律[20,21,28],而且也改变了河流有机碳的输运过程,使POC的输送主要集中在黄河调水调沙期间完成[26]。
三门峡水库是黄河上第一个大型水利枢纽工程,控制着黄河89%的水量和近100%的泥沙。目前三门峡水库独特的运行方式即通过枯水期的蓄水拦沙、汛期的调水调沙和敞泄的运行方式对黄河有机碳的输送产生了深刻的影响。① 在枯水季节三门峡水库主要进行蓄水拦沙,大大改变了有机碳的输送结构,使FDOC/FPOC大于1,即在水库的影响下POC被拦截而以DOC输送为主。② 在调水调沙阶段三门峡水库又将拦蓄在水库里的大量泥沙排出水库,使FDOC/FPOC远小于1,即水库通过调水调沙在短时间内又将拦蓄在水库中的大量POC输送到下游。③ 在汛期的8~9月,随着黄河中游的汾河和渭河等黄河主要泥沙来源的支流进入汛期,三门峡水库处于敞泄状态,这时三门峡站有机碳的输送基本未受三门峡水库的影响。
Parks等对美国亚利桑那州“Verde河流-水库”系统进行研究表明[15],约72%的POC被水库截留;Kim等研究也表明[33],河水进入水库后因沉降作用使得超过70%的POC滞留在水库。长江三峡工程是当今世界上最大的水利枢纽工程,自从三峡水库运行以来,POC输送量大幅减小[34~36]。另外对三峡水库下游大同站的POC通量研究表明,三峡水库运行后大同站没有出现POC集中输送的现象,如2011年7月大同站POC通量最多,也仅占全年POC通量的19.4%[34]。
黄河三门峡水库对河流有机碳输送的影响与其它河流上的水库明显不同,它不仅在枯水期拦蓄了大量POC,而且还在汛期通过调水调沙的方式将拦蓄在水库中的大量POC输送到下游,此外8~9月水库处于敞泄状态,将上游输送过来的有机碳直接输送到下游。
1） 在三门峡水库调水调沙期间,三门峡站POC含量随着TSS含量的急剧增加而同步增加,两者呈现出非常显著的相关性;DOC含量却没有明显的变化趋势。在1个水文年内,POC含量有明显季节性变化,7~9月POC含量高其它月份POC含量偏低;DOC含量也有明显季节性变化,1~2月和8~9月DOC含量高,其它月份DOC含量低。
2） 三门峡站DOC年通量为7.56万t,其中9月最多,其次是8月,分别占全年DOC通量的22.46%和18.92%;三门峡站POC年通量为124.8万t,其中7~9月完成了全年POC输送量的97.98%。
3） 在汛期的7~9月三门峡站有机碳的输送以POC为主,在枯水期三门峡站有机碳的输送以DOC为主;从全年来看三门峡站有机碳的输送以POC为主,POC输送量约为DOC的16.5倍。
4） 三门峡水库对流黄河有机碳输送的影响明显不同于其它河流上的水库,它在枯水期大量拦蓄POC,有机碳输送以DOC为主;7月初三门峡水库又通过调水调沙将拦蓄在水库中的POC大量输送到下游,这时POC输送量远大于DOC;8~9月三门峡水库处于敞泄状态,将上游输送过来的有机碳直接输送到下游。
The authors have declared that no competing interests exist.
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This article is in Free Access Publication and may be downloaded using the “Download Full Text PDF” link at right.
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The goal of this paper is to give some indications on the concept of affect in psychoanalysis. There is no single theory of affect, and Freud gave successive definitions, which continue to be deepened in contemporary psychoanalysis. We review some steps of Freud works on affect, then we look into some present major questions, such as its relationship to soma, the nature of unconscious affects and the repression of affect, which is particularly developed in the field of psychoanalytic psychosomatic. From Freud's definitions of affect as one of the drive representative and as a limit-concept between the somatic and the psychic, we develop some major theoretical perspectives, which give a central place to soma and drive impulses, and which agree on the major idea that affect is the result of a process. We then note some parallelism between psychoanalysis of affect and psychology and neurosciences of emotion, and underline the gaps and conditions of comparison between these different epistemological approaches.
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Reports on the effect of Silicate on the growth of algal and species composition resulting from hydrological alterations. Discussion of the silicon and carbon link which has impacted the ecosystem structure in coastal areas; Details of hydrological alterations which have increased river inputs; Outlook for the estuarine and coastal ecosystems.
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The sediment load delivered from the Huanghe (Yellow River) to the sea has decreased sharply to 0.15聽脳聽10 9 metric tons per year (0.15Gt/yr) between 2000 and 2005, and now represents only 14% of the widely cited estimate of 1.08Gt/yr. The river seems to be reverting to the pristine levels characteristic of the middle Holocene, prior to human intervention. Datasets from 1950 to 2005 from four key gauging stations in the main stream reveal distinct stepwise decreases in sediment load, which are attributed to both natural and anthropogenic impacts over the past 56yr. Completions of two reservoirs, Liujiaxia (1968) and Longyangxia (1985), in the upper reaches of the river and their joint operations have resulted in stepwise decreases in sediment load coming from the upper reaches. Effective soil conservation practices in the middle reaches since the late 1970s, combined with the operation of the Sanmenxia and Xiaolangdi reservoirs, have also caused stepwise decreases in sediment load at Huayuankou in the middle reaches, but the decrease differs from that observed in the upper reaches. Decrease in precipitation is responsible for 30% of the decrease in sediment load at Huayuankou, while the remaining 70% is ascribed to human activities in the river basin, of which soil conservation practices contribute 40% to the total decrease. Sediment retention within reservoirs accounts for 20% of the total sediment load decrease, although there was notable sediment retention within the Xiaolangdi reservoir from 2000 to 2005. The remaining 10% of the decrease in sediment load is a result of the operation of reservoirs in the upper reaches. In the lower reaches, 20% of the sediment passing Huayuankou has been lost as a result of channel deposition and water abstraction. Soil conservation practices and the operation of reservoirs have lowered the content of coarser sediment ( D 聽>聽0.05mm) at Huayuankou, and reduced channel deposition in the lower reaches. In contrast, sediment loss owing to water abstraction in the lower reaches has increased considerably as water consumption for agricultural needs has increased. Therefore, the combined effects of climate change and human activities in the upper, middle, and lower reaches have resulted in stepwise decreases in the sediment load delivered from the Huanghe to the sea. The Huanghe provides an excellent example of the altered river systems impacted by climate change and extensive human activities over the past 56yr. Further dramatic decreases in sediment load and water discharge in the Huanghe will trigger profound geological, morphological, ecological, and biogeochemical responses in the estuary, delta, and coastal sea.
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The sharp decrease in suspended sediment supply from China’s rivers to the sea:anthropogenic and natural causes [J].https://doi.org/10.1623/hysj.54.1.135 URL [本文引用: 3] 摘要
Based on data from river gauging stations, the multi-year variations in suspended sediment flux (SSF) from China's nine major rivers to the sea were examined. The decadal SSF decreased by 70.2%: from 1.81 Gt/year for 1954–1963 to 0.54 Gt/year for 1996–2005. The decrease in SSF was more dramatic in the arid northern region than in the wet southern region; from north to south, the SSF decreased by 84% in the Yellow River, 42% in the Yangtze River, and 22% in the Pearl River. Dam construction was the principal cause for the decrease in SSF. At present, approximately 2 Gt/year of sediment is trapped in the reservoirs within the nine river basins. Reduced precipitation and increased water extraction and sand mining have also played a role in the decrease in SSF. Although water and sediment conservation programmes have not counteracted the influence of deforestation, they have enhanced the decrease in SSF in recent years. It is concluded that human activity has become a governing factor on riverine sediment delivery to the sea in China.
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| [22] |
Organic matter in large turbid rivers:the Huanghe and its estury [J]. |
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Carbon inputs and distribution in estuaries of turbid river:the Yangtze and Yellow Rivers(China) [J].https://doi.org/10.1016/0304-4203(93)90229-H URL [本文引用: 2] 摘要
Particulate and dissolved organic and inorganic carbon concentrations were measured in the Yang Tze (Changjiang) and Huanghe (Yellow) river estuaries, during two different seasons. During the winter, the organic matter in the suspended load of both estuarine systems was dominantly of terrestrial origin, while in the summer, there were significant contributions from aquatic production. In these turbid rivers, there is a strong positive correlation between the concentrations of total suspended matter and particulate organic carbon, probably because biological production is inhibited when turbidity exceeds a certain limit. Dissolved organic carbon (DOC) does not exhibit a conservative behavior in these estuarine systems. High dissolved organic carbon values in bottom water samples suggest remobilization of DOC from near-surface, bottom sediments. Dissolved inorganic carbon concentrations were very high in the Huanghe River, and the trend in the calculated saturation indices for calcite suggests precipitation of carbonate in this estuarine system. There is no such evidence for carbonate precipitation in the Yang Tze River.
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| [24] |
黄河利津站碳输运年内变化及入海通量估算 [J].URL 摘要
通过2010年7月～2011年7月每月在黄河利津浮桥进行的水质观测,分析了黄河入海各形态碳的季节性变化及其可能原因,估算了各形态碳的月际及全年入海通量。结果表明,黄河利津站水体各形态碳浓度年内变化显著。溶解无机碳（DIC）浓度汛期明显低于非汛期,全年平均浓度为3.098 mmol/L。溶解有机碳（DOC）平均浓度为2.39 mg/L,全年变化趋势表现为春季最高,夏季次之但各月间变化幅度较大,冬季最低。DOC与溶解氧饱和度呈现负相关关系,陆源和人为污染输入的迹象明显。颗粒有机碳（POC）平均浓度为12.92 mg/L,与水体中悬浮颗粒物（TSS）含量线性关系良好,水体中的TSS含量是控制DOC/POC输运比例的主要因素。利津站DIC、DOC浓度在年度尺度上与径流量呈现负相关关系,稀释效应是其主体影响因素。但在雨致洪峰及调水调沙时期：泥沙输运量增大,无机碳酸盐固液平衡维持了较高的DIC浓度;强降雨地表冲刷、较高DOC浓度的库区水下泄,以及下泄水对下游干枯河道的冲刷,导致DOC浓度偏高。黄河各形态碳的月际入海通量整体表现出汛期高,非汛期低的特点,年内DIC、DOC及POC的年入海通量（以C计）分别为5.62×105t、3.97×104t和3.50×105 t。
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| [25] |
黄河干流有机碳的时空分布特征 [J].https://doi.org/10.3969/j.issn.1672-5174.2010.12.015 URL 摘要
通过2003—2009年多个航次对黄河干流DOC（溶解有机碳）和POC（颗粒有机碳）） 及相关参数的调查研究,结果表明：TSS（颗粒悬浮物）为91.42~8188 mg/L,POC为0.65~24.20 mg/L,POC%（POC/TSS×100%）为0.44%~2.21%,DOC为1.57~4.77 mg/L,有机碳沿程分布具有明显的空间特征。花园口水文年调查中有机碳含量与流量的季节变化密切相关,POC主要受冲刷影响,而DOC在不同季节分别体 现出冲刷、稀释或浓缩效应。修建水库和调水调沙这2个显著的人为干扰活动对黄河有机碳的性质及输运产生了截然不同的影响：库区自生源对有机碳的贡献明显大 于干流,DOC/POC为6.64~12.00,DOC是有机碳的主要形式,同时水库截流,颗粒物沉降降低了颗粒有机碳的输运量,而调水调沙却加强了有机 碳的输运,该时期DOC/POC为0.01~0.47,POC是有机碳输运的主导形态。
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| [26] |
Impact of human activities on organic carbon transport in the Yellow River [J].https://doi.org/10.5194/bg-10-2513-2013 URL [本文引用: 6] 摘要
Using data from four field investigations between 2003 and 2009 along the Yellow River mainstream, we examined the transport features and seasonal variations of organic carbon, with a focus on contrasting the impacts of human activities with those of natural processes. Particulate organic carbon (POC) in the Yellow River originated mainly from the Loess Plateau, and thus the POC content in suspended sediments was much lower than in the world's other large rivers. Owing to both natural and human influences, dissolved organic carbon (DOC) has only a weak correlation with discharge. DOC varied as a result of human activities such as agricultural irrigation and pollution in the whole basin except for the upstream Qinghai-Tibetan Plateau. Our study also suggested that while reservoirs are a POC sink over short periods, a long-term POC storage flux cannot be easily estimated as discharge and sediment regulations have completely changed the relationship between the fluxes of water, sediments, and rainfall. However, this carbon sink can be obtained reliably through high-frequency sampling over long time periods. In addition, the annual water and sediment regulation (WSR) scheme has imposed an extremely severe human disturbance on the transport pattern of river organic carbon. Our study demonstrated for the first time that in a WSR event of less than 20 days, large proportions of the annual DOC (35%) and POC (56%) fluxes of the Yellow River were transported to the estuarine and coastal zone, potentially influencing estuarine and coastal geochemistry and ecosystems profoundly.
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| [27] |
Spatial and seasonal variability of organic carbon transport in the Yellow River,China [J].https://doi.org/10.1016/j.jhydrol.2013.06.018 URL Magsci [本文引用: 6] 摘要
In this study, we examined the spatial and seasonal variability in the concentrations of dissolved and particulate organic carbon (DOC and POC) of the Yellow River. Weekly samples of water and suspended solids were collected along the main stem channel between July 2011 and July 2012 for the upstream Toudaoguai and Tongguan stations, and between August 2008 and July 2012 for the downstream Lijin station near the river mouth. The DOC export at the upstream two stations was primarily controlled by hydrological events such as melting of ice and snow with high DOC concentrations occurring in spring. In contrast, it was more affected by human activities, mainly reservoir regulation, at the lowermost Lijin station. Lower DOC concentration in the wet season indicates that most of the leachable DOC in surface soils may have largely been flushed away by spring floods. In addition, it is also likely due to dilution effect of the rapidly increased water discharge. As a result of low organic carbon content in the parent soils, the Yellow River sediments were characterized by low POC content (POC%). The averaged POC% at Toudaoguai, Tongguan, and Lijin was 0.48%, 0.47%, and 0.37%, respectively, which is significantly lower than the global mean of around 0.95%. The POC% decreased exponentially with total suspended solids (TSS) concentration. This is likely due to the dilution of riverine POC, because high TSS generally means a higher proportion of coarse sediments that have more mineral matter. During the study period, the total DOC and POC fluxes into the ocean were estimated at 0.06 x 10(12) g/yr and 0.41 x 10(12) g/yr, respectively. Combining our previous estimate of dissolved inorganic carbon (DIC) export shows that the Yellow River transports a carbon flux of 1.52 x 10(12) g/yr into the Bohai Sea, accounting for about 0.19% of the global total riverine carbon flux (DOC + POC + DIC). The extremely low DOC/POC ratio represents the lowest level among major world rivers, which is consistent with its intense soil erosion and highlights the effect of soil erosion on organic carbon export. (C) 2013 Elsevier B.V. All rights reserved.
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| [28] |
Recent changes in sediment delivery by the Huanghe (Yellow River) to the sea:Causes and environmental implications in its estuary [J].https://doi.org/10.1016/j.jhydrol.2010.07.030 URL [本文引用: 2] 摘要
SummaryOver the past 60 years, climate change and human activities in the Huanghe (Yellow River) basin have changed the river system. In particular, construction of large reservoirs and soil-conservation practices within the river basin have reduced sediment flux to the sea by 藴90% and increased the grain size of suspended sediment delivered to the sea (30 渭m now versus 18 渭m before in median grain size). Scouring of the channel in the lower reaches has added a new sediment source to those derived from the loess region of the middle reaches. Before construction of the Xiaolangdi Reservoir at the downstream end of the middle reaches, suspended sediment concentrations at station Lijin, the last hydrographic station before the river enters the sea, were high enough (>35 kg/m ) in the flood season to offset the density contrast between freshwater and ambient seawater. Thus, hyperpycnal flows developed along the subaqueous slope at the river mouth during the flood season. Observations from two cruises near the Huanghe river mouth, one before and one after the operations of the Xiaolangdi Reservoir, suggest that buoyant hypopycnal plumes, rather than hyperpycnal plumes, have occurred at the river mouth since the dramatic changes in concentration and grain size of suspended sediment discharged to the sea. The rapid decrease of sediment discharge to the sea and the increase of grain size of suspended sediments not only changed the sediment dispersal pattern at the river mouth, but also modified the shoreline and subaqueous slope. The effects of climate change and human activities in the river basin have been transferred along the hydrological pathway to the estuary and delta, and have changed estuarine sediment dynamics and delta morphology. The Huanghe presents an illustrative example of river basin-coastal zone interactions in the context of climate change and human activities.
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| [29] |
黄河流域水污染分析及水环境保护措施 [J].https://doi.org/10.3969/j.issn.1009-6825.2009.26.101 URL [本文引用: 1] 摘要
对黄河流域水资源污染及其污水排放现状进行了介绍,在此基础上,分析了黄河流域废污水排放情况、水质污染程度、污染物的组成等情况,并提出水资源的保护措施.
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| [30] |
Predicting the oceanic input of organic carbon by continental erosion [J].https://doi.org/10.1029/95GB02925 URL [本文引用: 1] 摘要
Empirical models were developed to describe relationships between the climatic, biologic, and geomorphologic characteristics of major world rivers and the observed dissolved and particulate carbon fluxes. The main purpose of the study was to determine the best regression models to describe river carbon flux at a global scale. Model parameters were grouped in all possible combinations and in a way to minimize the effects of multicollinearity. All parameter combinations were then tested individually. A model was developed with parameters which corresponded well to field results and global carbon fluxes which were close to previous estimates. The model was also used to relate the variability of annual carbon fluxes to the environmental variability of river basins. The statistical approach allows only a general view, but is capable of identifying the principal factors controlling global organic carbon flux. 111 refs., 5 figs., 4 tabs.
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| [31] |
Seasonal fluxes and source variation of organic carbon transported by two major Chinese Rivers:The Yellow River and Changjiang (Yangtze)River [J].https://doi.org/10.1029/2011GB004130 URL [本文引用: 3] 摘要
A one-year study was carried out to investigate the seasonal fluxes and source variation of organic carbon transported by two major Chinese rivers, the Yellow River and Changjiang. In 2009, the Yellow River and Changjiang transported 3.20 x 10(10) g and 1.58 x 10(12) g DOC and 3.89 x 10(11) g and 1.52 x 10(12) g POC, respectively. The dominant input of the terrestrial organic matter occurred during the high discharge period from June to July for the Yellow River and from June to August for Changjiang, accounting for 36-44% of the DOC and 72-86% of the POC transported by the two rivers in 2009. The Yellow River transported much higher concentrations of inorganic carbon than organic carbon, while a reverse trend was found in the Changjiang, indicating the different sources of carbon discharged by the two rivers. Using radiocarbon and stable carbon isotope measurements, we identified the different sources and seasonal variations of organic carbon transported by the Yellow River and Changjiang. The Yellow River carried old POC with radiocarbon ages ranging from 4000 to 8000 years, while POC transported by Changjiang had a relatively younger C-14 age ranging from 800 to 1060 years. The C-14 ages of DOC were relatively younger (305-1570 years) and showed less variation between the two rivers. The seasonal variations found in C-14 ages of DOC and POC indicate that a large fraction of recent-fixed labile organic carbon was transported by the two rivers in the spring and summer months. The different sources and seasonal variations in both fluxes and sources of organic carbon transported by the Yellow River and Changjiang could have an important influence on the biogeochemical cycle and ecosystems in the estuaries and adjacent coastal waters of the East China Sea.
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| [32] |
Carbon transport by the Yangtze (at Nanjing)and Huanghe (at Jinan) Rivers, People’s Republic of China [M] |
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Distribution and loading of organic carbon in a deep reservoir,Lake Soyang,Korea [J]. |
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长江干流有机碳的时空输运特征及三峡工程对其影响 [J].https://doi.org/10.3969/j.issn.1672-5174.2011.01.018 URL [本文引用: 2] 摘要
2006-04,2008-04,2008-05沿长江干流采集 表层水样,并于2006-05～2007-05在下游大通站进行每月2次、为期1 a的连续观测,测定溶解有机碳(DOC)、颗粒有机碳(POC)及总悬浮物(TSM).结果表明:长江重庆以上江段DOC浓度较低,重庆至河口由于人为污 染排放DOC表现出高值;干流POC与TSM显著正先关,POC%(TSM)随TSM含量增大呈负指数关系下降.大通站有机碳浓度及通量均表现出明显的季 节性,2006-06～2007-05全年经大通站进入河口的DOC、POC通量分别为1.17×106tC和1.88×106tC,其中洪季(5～10 月)输运的有机碳占到总有机碳的70%,组成以颗粒态为主.三峡水库135 m及156 m蓄水后,泥沙在库区的沉降作用显著影响长江POC的输运特征及入海通量;从目前观测结果看,三峡库区DOC浓度并没有表现出明显的升高趋势,可能与水库 运行时间尚短有关.
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| [35] |
三峡水库建设对长江下游颗粒有机碳通量及碳同位素组成的影响 [J].URL 摘要
2008年4月至2009年4 月,在南通长江干流每周采集一次表层悬浮物样品,共51个,分析了其粒度、颗粒有机碳(POC)、颗粒氮(PN)含量以及有机碳同位素(δ13Corg) 组成,研究了下游干流颗粒有机碳组成的季节性变化特征。悬浮物的平均粒径在一年内变化不明显,而POC和PN含量呈现洪季缓慢减小,枯季增加的趋 势;δ13Corg值的变化正好相反,介于–24.1‰与–25.6‰之间,具有明显的季节性变化规律。POC/PN比值的季节性变化不显著。平均粒径与 POC、PN及δ13Corg值均无显著相关性。颗粒有机碳的总通量及陆源有机碳的贡献具有明显的季节性变化,陆源有机质所占的比例呈现洪季高、枯季低的 特点,同径流量和含沙量关系密切。与前人在长江南通段的研究结果比较揭示,三峡水库建设后长江下游干流颗粒有机质组成与入海陆源有机碳通量发生明显变化, 其对河口及边缘海的生物地球化学循环的潜在影响值得关注。
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| [36] |
长江有机碳通量的季节变化及三峡工程对其影响 [J].https://doi.org/10.3321/j.issn:1000-6923.2007.02.022 URL [本文引用: 1] 摘要
2003年6月-2005年7月在长江口每月采集表层水样,测定溶解有机碳（DOC）和颗粒 有机碳（POC）.结果表明,DOC和POC平均浓度分别为1.59±0.21和0.91±0.42mg/L,其中枯季的DOC浓度较洪季高,而POC则 呈相反趋势.POC浓度与水体中总悬浮颗粒物（TSM）浓度有显著性正相关关系,在TSM中的POC%随着TSM浓度的增加而减小.2003,2004年 长江的DOC通量分别为1.32×10^6t和1.20×10^6t,POC通量分别为2.69×10^6t和1.63×10^6t,约76%的总有机碳 在洪季输送入海,组成以颗粒态为主.2003-2004年间POC通量急剧减少,DOC通量与POC通量的比值迅速增大,可能与三峡水库对颗粒物的拦蓄、 改造及富营养化有关.
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