Longest River In China Research Articles

Record Setting 3,300-m Distance by Horizontal Directional Drilling of a 711-mm-Diameter Pipeline Crossing the Yangtze River

AbstractThis paper describes a record setting project in the horizontal directional drilling field involving twin pipes with a diameter of 711 mm and a length of 3,300 m. The Yangtze River is the longest river in China. The Jiangdu-Rudong gas pipeline, which is part of the Chinese gas pipeline trunk network, was constructed to transport gas from the north side to the south side of the River. The width of the river surface is 3,000 m, and the length of the crossing is 3,300 m. It was recommended by engineers that twin pipes with a diameter of 711 mm be used instead of the existing pipe with a diameter of 1,016 mm. The required depth of penetration for the crossing was determined by an analysis of 43 years of historical river scour data from 1966 to 2009 combined with a calculated result using a river scour depth formula. The recommended construction scheme included arranging two drilling rigs, laying magnetic-signal submarine cable, using the intersect method, and designing a new flat-barrel combination-ty...

DNA barcoding and evaluation of genetic diversity in Cyprinidae fish in the midstream of the Yangtze River.

The Yangtze River is the longest river in China and is divided into upstream and mid‐downstream regions by the Three Gorges (the natural barriers of the Yangtze River), resulting in a complex distribution of fish. Dramatic changes to habitat environments may ultimately threaten fish survival; thus, it is necessary to evaluate the genetic diversity and propose protective measures. Species identification is the most significant task in many fields of biological research and in conservation efforts. DNA barcoding, which constitutes the analysis of a short fragment of the mitochondrial cytochrome c oxidase subunit I (COI) sequence, has been widely used for species identification. In this study, we collected 561 COI barcode sequences from 35 fish from the midstream of the Yangtze River. The intraspecific distances of all species were below 2% (with the exception of Acheilognathus macropterus and Hemibarbus maculatus). Nevertheless, all species could be unambiguously identified from the trees, barcoding gaps and taxonomic resolution ratio values. Furthermore, the COI barcode diversity was found to be low (≤0.5%), with the exception of H. maculatus (0.87%), A. macropterus (2.02%) and Saurogobio dabryi (0.82%). No or few shared haplotypes were detected between the upstream and downstream populations for ten species with overall nucleotide diversities greater than 0.00%, which indicated the likelihood of significant population genetic structuring. Our analyses indicated that DNA barcoding is an effective tool for the identification of cyprinidae fish in the midstream of the Yangtze River. It is vital that some protective measures be taken immediately because of the low COI barcode diversity.

Excretion of manure-borne estrogens and androgens and their potential risk estimation in the Yangtze River Basin

The Yangtze River is the longest river in China, and the river basin spans one fifth of the area of the whole country. Based on statistical data, the excretion of manure-borne steroid hormones, including steroid estrogens (SEs) and steroid androgens (SAs), in 10 provinces of China within the region has been estimated. The potential environmental and ecological risk of manure-borne steroid estrogens to the surface water in this region was also assessed. The manure-borne SE and SA excretions in the 10 provinces and municipalities vary in the order: Sichuan>Hunan>Hubei>Yunnan>Jiangsu>Anhui>Jiangxi>Chongqing>Qinghai>Shanghai. The highest increase of manure-borne SEs (1434.3kg) and SAs (408.5kg) was found in Hunan and Hubei provinces, respectively, and the total excretion in 2013 was 65% more than 15years earlier in these two provinces. However, the emissions in Anhui and Shanghai decreased in this 15year period of time. Swine urine, chicken feces, cattle urine, and laying hen feces were considered the dominant sources of manure-borne E1, βE2, αE2, and SAs, respectively. Although Jiangsu province did not have the largest excretion of manure-borne SEs, it had the highest level of predicted 17β-estradiol equivalency (EEQs) value of 16.65ng/L in surface water because of the limited surface water resources. According to the lowest observable effect level of 10ng/L for 17β-estradiol, the manure-borne SEs in Jiangsu province might potentially pose ecological risk to its wild aquatic organisms.

Attribution of the changes in annual streamflow in the Yangtze River Basin over the past 146 years

Water resources in the Yangtze River, the longest river in China, are of great importance for the water security of China. In this study, 146 years (1865–2010) of streamflow data were used to investigate the changes in streamflow of the Yangtze River. The Mann-Kendall test and wavelet coherence analysis were used to test the change points in annual streamflow. The streamflow data, combined with the meteorological dataset of the Climatic Research Unit (CRU) from 1901 to 2010, showed that the Yangtze River streamflow changes occurred in four major periods over the past century: 1901–1930, 1931–1960, 1961–1990, and 1991–2010. The average annual streamflow for the four periods was 497.26, 499.11, 476.25, and 471.93 mm, respectively. The period from 1901 to 1930 was considered the baseline period for estimating the streamflow changes during the other three periods. We found that the streamflow increase during 1931–1960 was mainly influenced by climatic variation, while the streamflow decrease during 1961–1990 was mainly attributed to human activities because of tremendous population growth and rapid economic development. During the period 1991–2010, both climatic variation and human activities led to a decrease in streamflow, and human activities were still the main driving factor for the streamflow decrease. However, the contribution proportion of human activities to the streamflow decrease during 1991–2010 was much smaller than that during 1961–1990. The estimation results indicated that human activities have become the dominant driving factors of the streamflow changes in the Yangtze River Basin since 1961. Human activities, such as booming socio-economic development and fast population growth, have brought new challenges for water resources management in the Yangtze River Basin.

Time constraints for the Yellow River traversing the Sanmen Gorge

The Yellow River is the second longest river in China, a total course of 5464 km. The Yellow River traverses 30 gorges within its main course and the last one is the Sanmen Gorge. The timing of cut through the Sanmen Gorge indicates the final integration of the Yellow River. Previous geological surveys identify a paleolake in the Weihe Basin located west of the Sanmen Gorge; the lake was drained when the gorge was cut through. Using cosmogenic nuclide burial dating, we obtain ages of transition from lake to fluvial environments in the Weihe Basin and formation of fluvial terraces within the Sanmen Gorge. The timing of cut through the Sanmen Gorge is constrained to 1.3–1.5 Ma. Zircon U‐Pb age distributions further suggest that the Weihe, the largest tributary of the Yellow River running from west to east along the northern section of the Qinling Mountains, primarily flowed over the Sanmen Gorge, followed by the upper and middle Yellow River traversing 1.3–1.4 Ma ago. It appears that formation and integration of the Yellow River occurred in a short duration in the early Pleistocene, probably related to global climate changes.

Using 15N, 17O, and 18O To Determine Nitrate Sources in the Yellow River, China

Many previous studies have used δ(15)N and δ(18)O of nitrate (δ(15)NNO3 and δ(18)ONO3) to determine the nitrate sources in rivers but were subject to substantial uncertainties and limitations, especially associated with evaluating the atmospheric contribution. The Δ(17)O of nitrate (Δ(17)ONO3) has been suggested as an unambiguous tracer of atmospheric NO3(-) and may serve as an additional nitrate source constraint. In the present study, triple nitrate isotopes (δ(15)NNO3, Δ(17)ONO3, and δ(18)ONO3) were used for the first time to assess the sources and sinks of nitrate in the Yellow River (YR) basin, which is the second longest river in China. Results showed that the Δ(17)ONO3 of the water from the YR ranged from 0‰ to 1.6‰ during two normal-water seasons. This suggested that unprocessed atmospheric nitrate accounted for 0-7% of the total nitrate in the YR. The corrected δ(15)NNO3 and δ(18)ONO3 values with atmospheric imprints being removed indicated that the main terrestrial sources of nitrate were sewage/manure effluents in the upstream of the YR and manure/sewage effluents and ammonium/urea-containing fertilizer in the middle and lower reaches which made comparable contributions to the nitrate. In addition, there was a significant positive relationship between δ(15)NNO3 and δ(18)ONO3 values of river water (p < 0.01) which may signal the presence of denitrification. This study indicates that the triple nitrate isotope method is useful for assessing the nitrate sources in rivers, especially for the measurements of atmospheric nitrate contribution.

Geomorphology and environmental management of the Yellow River source zone

628 Geologic, climatic and anthropogenic factors have fashioned the distinctive landscapes and ecosystems of the Yellow River source zone (Brierley and Huang 2013; Figure 1). Located at the north-east corner of the Qinghai-Tibetan Plateau (QTP), at elevations between 2500 and 4500 m, this area has an arid/semi-arid climate. Many of these landscapes retain a significant imprint from Quaternary environmental changes. This mix of factors has induced marked variability in vegetation patterns and land use potential across this vast area, where land use practices have maintained grazing adapted ecosystems for several thousand years (Miehe et al. 2009). Despite the low population density, development pressures and climate change present significant threats to ecosystem values (e.g. Liu et al. 2012; Shapiro 2012). In recent decades, grassland and wetland degradation, alongside desertification, have placed significant stress upon land and water resources and biodiversity (including various iconic and endemic species, many of which are threatened or endangered). A sustainability focus recognizes that the costs of prevention of environmental degradation are significantly less than the costs of repair (if indeed repair is realistically achievable). Effective approaches to environmental protection and rehabilitation of rivers, wetlands and grasslands build upon a landscape platform, recognizing inherent links between geodiversity and biodiversity (Blue et al. 2013; Li et al. 2012). The Yellow River originates from the Bayankala Mountains atop the Qinghai–Tibetan Plateau of Qinghai Province, from which it flows through eight provinces and autonomous regions before emptying into the Bohai Sea north of the Shandong Peninsula. With a length of over 5400 km, it is the second longest river in China and the tenth longest in the world. The basin contains approximately 9 % of China’s population and 17 % of its agricultural area (Pietz and Giordano 2009). From its source at an elevation of around 4600 m, the upper Yellow River flows through a series of deep gorges and basins atop the QTP (Nicoll et al. 2013). Alluvial reaches in wide and shallow valleys with gentle valley slopes are characterized by a wide range of river types, including anabranching, anastomosing, braided and meandering reaches (see Figure 1; Blue et al. 2013; Li et al. 2013; Yu et al. 2013). Upstream from Hekouzhen in Inner Mongolia, the upper Yellow River contributes around 200 × 108 m3 per year (about 56 % of the total annual runoff of the basin). However, the upper Yellow River has a low sediment yield, generating about 1 × 108 t suspended sediment per year (less than 10 % of the annual suspended sediment load of the whole river basin) (Wang et al. 2007). Hence, while the source zone generates the largest portion of the total flow of the Yellow River, the majority of sediment is generated from the Loess Plateau in the middle reaches of its basin. Unlike the middle and lower reaches, which are Geomorphology and Environmental Management of the Yellow River Source Zone

Assessing regional virtual water flows and water footprints in the Yellow River Basin, China: A consumption based approach

The Yellow River, the second longest river in China, is facing increasing water scarcity due to rising water consumption of a fast growing economy and an increasingly urbanized population with water-intensive consumption patterns. The Yellow River Basin (YRB) is divided into three regions: the upper, middle and lower reaches; each with very different characteristics in terms of water resources, economic structure and household income and consumption patterns. Virtual water has been recognised as a potentially useful concept for redistributing water from water-rich to water-poor regions. In this study, we develop a Multi-Regional Input–Output model (MRIO) to assess the regional virtual water flows between the three reaches of the basin and the rest of China distinguishing green and blue water, as well as rural and urban household water footprints. Results show that all three reaches are net virtual water exporter, i.e. production and consumption activities outside the basin also put pressure on the water resources in the YRB. The results suggest a reduction of the export of virtual blue water that could instead be used for producing higher value added but lower water-intensive goods. In particular, the lower reach as the most water scarce region in the basin should increase the import of water intensive goods, such as irrigated crops and processed food products, from other more water abundant regions such as the South of China. Thus, trading virtual water can help sustain the economic growth of the regions within the basin thus easing the pressure from water shortage. In addition, there is a huge gap between urban and rural household water footprints in the basin. The average urban household’s water footprint is more than double the water footprint of a rural household in the basin. This is due to the higher urban household consumption of water-intensive goods and services, such as processed food products, wearing apparel and footwear, hotel and catering services and electricity.

Fractal characteristics of the main channel of Yellow River and its relation to regional tectonic evolution

Yellow River is the second longest river in China's, and its mainstream passes four different tectonic provinces in North China from west to east. Here, we exploit the relationship between the fractal dimensions of Yellow River channel and the tectonic provinces it flows through. The fractal dimension series D i was obtained for the main channel of Yellow River by applying the successive shift divider method using several different scale ranges. The results show that the magnitude of D i values is related to the uplifting intensity and time of the tectonic provinces where the river channel is located. The intenser and younger the uplifting of the tectonic provinces, the larger the fractal dimension D i of the channel when the scale range is taken as 200 nodes (300 km). Using the same scale range, the D i values also are calculated by applying a successive shift box method. The differences between results from both methods are discussed.

China’s Largest Scale Ecological Migration in the Three-River Headwater Region

Over the past three decades, China’s economic growth has been the fastest among major nations. However, its environmental degradation has also accelerated (Liu and Diamond 2008). To mitigate the degraded environment, China has been implementing large-scale conservation programs, including the Key Shelterbelt Construction Program, Beijing-Tianjin Sandstorm Control Program, Wildlife Conservation and Nature Reserve Development Program (Ouyang 2007), Forest Eco-Compensation Program (Ministry of Finance of China and State Forestry Administration of China 2007), the Natural Forest Conservation Program, and the Grain to Green Program (Zhang et al. 1999; Xu et al. 2006; Liu et al. 2008). The Three-River Headwater (TRH, Sanjiangyuan, Fig. 1) region is located in the core of the Tibet Plateau, China, and covers 363,000 km2 with the average altitude of 4,200 m. It is the world’s highest altitude region with the richest biodiversity, and contains China’s highest elevation and largest area wetlands (Committee 2009). The TRH region, known as China’s, and even Asia’s water tower, is the headstream of the Yangtze River (Chang Jiang, the longest river in China and the third longest in the world), the Yellow River (Huang He, the second longest river in China, referred to as the cradle of the Chinese civilization), and the Lantsang River (Lancang Jiang, an international river called the Mekong River outside China). This region provides 25% of the water volume of the Yangtze River, 49% of the Yellow River, and 15% of the Lantsang River (Qin et al. 2008). In 2000, the Chinese government established the TRH reserve with an area of 152,300 km2—a land area larger than England and Wales combined, to protect this most unique and fragile ecosystem. Fig. 1 China’s water tower. Based on the MODIS product (MOD09AlV5), 12 August 2008 The TRH region suffers from global warming and the explosive increase in the intensity and extent of human activities (overgrazing, poaching of plants and wildlife, gold mining, etc.) (Zhao and Zhou 2005). Rangelands are severely overgrazed, and 58% of rangelands are moderately to severely degraded. Soil erosion has deteriorated about 26.5% of the region’s total land area. Rat infestation is widespread and the number of mouse-hole per hm2 is 1,335. Draught-up days of rivers are increasing (Lu 2007). The average annual runoff decreased more than 20% during the past 50 years (Qinghai Provincial Government 2005). Nearly one-fifth of its species are threatened (Cai 2008). The environmental degradation is also causing economic losses, and even brought about so-called “ecological refugees.” For example, Maduo County was one of the richest counties of the country in the early 1980s; however, it is now one of the 10 poorest counties, mainly due to ecological degradation caused by overgrazing (Gu et al. 2005). The deteriorating ecosystems prompted China to take an unprecedented conservation action—the Ecological Protection and Restoration Program (EPRP) in the TRH region in 2005 (Engineering Consulting Center of Qinghai Province 2005). The EPRP conserves and rehabilitates ecological functions through ecological migration, grazing bans, wetland protection, and harnessing degraded grassland. The EPRP is regarded as another large landmark project after the Development of the West Regions and the Qinghai–Tibet Railway. The Ecological Migration Program (EMP) among the EPRP in the TRH region, meaning local residents should move out from the reserve to restore the ecosystem and protect the environment, is deemed the country’s largest scale ecological migration for ecological compensation. A total of 7,500 million yuan (at present, $1 U.S. = 6.8 yuan) was budgeted for the EPRP, and 1,500 million yuan was allocated for the EMP. By the end of this program in 2010, almost all local Tibetan race residents are expected to be relocated to protect the vulnerable environment.

Nitrobenzene biodegradation ability of microbial communities in water and sediments along the Songhua River after a nitrobenzene pollution event

More than 100 t of nitrobenzene (NB) and related compounds were discharged into the Songhua River, the fourth longest river in China, because of the world-shaking explosion of an aniline production factory located in Jilin City on November 13, 2005. As one of the efforts to predict the fate of residual NB in the river, NB biodegradation abilities by microbes in the water and sediments from different river sections were evaluated systematically. The results indicated that microbial communities from any section of the river, including one section at the upper stream of the NB discharging point, had the ability to biodegrade NB under aerobic (for river water samples) conditions at 22 +/- 1 degree C or anaerobic (for sediment samples) conditions at 10 +/- 1 degree C. NB degradation rates of microbial communities in the downstream sites were markedly higher than those in the upstream site, indicating that NB degradation abilities were enhanced because of the pollution of NB. Aerobic degradation got neglected at a temperature of 10 degrees C or lower. The production of nitrosobenzene and aniline during aerobic biodegradation suggested the existence of at least two different NB degradation pathways, and the occurrence of the catechol-2,3-dioxygenase (C230) gene and the significant decrease of dissolved organic carbon (DOC) indicated that NB could be mineralized under aerobic conditions. Although it was a fact that the river have frozen-up during the NB accident, it was speculated that biodegradation was not the major process responsible for the decrease of NB flux in the river.

Eco-Environmental Degradation in the Source Region of the Yellow River, Northeast Qinghai-Xizang Plateau

The Yellow River is the second longest river in China and the cradle of the Chinese civilization. The source region of the Yellow River is the most important water holding area for the Yellow River, about 49.2% of the whole runoff comes from this region. However, for the special location, it is a region with most fragile eco-environment in China as well. Eco-environmental degradation in the source region of the Yellow River has been a very serious ecological and socially economic problem. According to census data, historical documents and climatic information, during the last half century, especially the last 30 years, great changes have taken place in the eco-environment of this region. Such changes are mainly manifested in the temporal-spatial changes of water environment, deglaciation, permafrost reduction, vegetation degeneracy and desertification extent, which led to land capacity decreasing and river disconnecting. At present, desertification of the region is showing an accelerating tendency. This paper analyzes the present status of eco-environment degradation in this region supported by GIS and RS, as well as field investigation and indoor analysis, based on knowledge, multi-source data is gathered and the classification is worked out, deals with their natural and anthropogenic causes, and points out that in the last half century the desertification and environmental degradation of this region are mainly attributed to human activities under the background of regional climate changes. To halt further degradation of the environment of this region, great efforts should be made to use land resources rationally, develop advantages animal agriculture and protect the natural grassland.

Assessment and exploitation of the waterfront resources in the middle and lower reaches of the Yangtze River

Waterfront resources are important and special kind of natural resources in the marginal area between land and water. The Yangtze River, the longest river in China, is not only rich in waterfront resources, but also has favorable development conditions with great potentiality. Aided by large-scale underwater topographic map, the major factors of the waterfront resources in the middle and lower reaches of the Yangtze River, such as the stability, the water depth and the natural conditions for port construction, are assessed in this paper respectively on the basis of the overall investigations. The results show that: (1) the waterfront resources are abundant in the middle and lower reaches of the Yangtze River, but lack of perfectly combined high grade waterfront; (2) there exists an obvious regional difference in the natural quality of the waterfront along the Yangtze; (3) the fore-bank water depth and waterfront stability are the main natural factors related to the waterfront quality in the middle and lower reaches of the Yangtze River; (4) the waterfronts along the Yangtze are mainly used for port, warehouse and industrial purposes; and (5) the waterfronts near important cities are highly used, especially the high-quality waterfronts. In addition, some suggestions for the development and utilization of the waterfront resources are presented in this paper.

Xiling Bridge over the Yangtze River, China

The Yangtze River is the longest river in China. The Xiling Bridge crosses the Yangtze 4.5 km downstream from the mammoth Three Gorges Dam project. Building a bridge on China’s busiest waterway, near the vast construction site of the Three Gorges Dam, presented many challenges. In addition, the owner specified that the bridge be opened to traffic as quickly as possible. Thus, prime considerations in the design phase of the bridge were how to minimize interference with the navigation channel and how to avoid disruptions during construction.