Assessment of the water resource carrying capacity based on the ecological footprint: a case study in Zhangjiakou City, North China.

With the rapid economic development in the past decades, industrialization and urbanization in China has also rapidly developed and will continue in the next decades. However, the regional water shortage has posed great challenges for the sustainable development of big cities especially in north China. Here, we used the water ecological footprint model combined with the system dynamic model to assess the water resource carrying capacity and its sustainability in Zhangjiakou City, a typical water shortage city in north China.

[Analysis of algal blooms in Da-Ning River of Three Gorges Reservoir].

According to the survey conducted from Apr. to Jun. 2007 and from Apr.

[Nitrogen forms and its distribution character in immerged and water-level-fluctuating zone soils of the backwater reach from input river of Three Gorges Reservoir].

This study measures the contents of different nitrogen forms in the immerged soils and the soils of water-level-fluctuating zone of the backwater area from input river of Three Gorges Reservoir, and analyzes the relationship between nitrogen forms and environmental parameters. The results indicates that: (1) Content of TN in the surface immerged soils ranged from 436.0 to 921.

Phragmites australis and Typha orientalis in removal of pollutant in Taihu Lake, China.

Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P < 0.01), with the reduction of 76%-87% and 52%-63% for P.

Effect of treatment with probiotics as water additives on tilapia (Oreochromis niloticus) growth performance and immune response.

A feeding trial was conducted for 40 days to delineate the effect of treatment with probiotics as water additives on tilapia (Oreochromis niloticus) growth performance and immune response. About 360 juveniles were randomly distributed into four treatment groups, each with three replicates. Different probiotics (T-1, Bacillus subtilis B10; T-2, Bacillus coagulans B16; T-3, Rhodopseudomonas palustris G06) were added to the water of tanks at final concentration of 1 x 10(7) cfu ml(-1) every 2 days, with no probiotic added to control tanks.

Toxic effects of fluoranthene and copper on marine diatom Phaeodactylum tricornutum.

To investigate the effects of polycyclic aromatic hydrocarbons (PAHs) and metals on the population reproduction, antioxidative defense system and cell ultrastructure of the marine diatom, fluoranthene and Cu2+ were selected to test their toxicity to Phaeodactylum tricorntum, in the laboratory. The results indicated that both fluoranthene and Cu2+ inhibited population reproduction of P. tricorntum.

Heavy metal pollution in Tianjin Bohai Bay, China.

The contamination levels and distribution characters of heavy metals in coastal waters and sediments from Tianjin Bohai Bay, China were examined. Pb and Zn were found as the main heavy metal pollutants in the coastal waters of the bay. High levels of Pb and Zn appeared especially near the estuary, indicating that river discharge was the main pollution source.

[Analysis of phosphorus distribution characters and their sources of the major input rivers of Three Gorges Reservoir].

The seasonal characters of the water flux and suspended substance, phosphorus in the water of input rivers of Three Gorges Reservoir (TGR) were discussed, and the their distributions among three major input rivers (Changjiang river, Jialingjiang river and Wujiang river) were studied, according to the survey conducted from Jan. 2004 to Dec. 2005.

[Analysis of nitrogen distribution characters and their sources of the major input rivers of Three Gorges Reservoir].

According to the survey conducted from Jan. 2004 to Dec. 2005, the seasonal characters of nitrogen in the water of input rivers of Three Gorges Reservoir (TGR) were discussed, and the forms and distributions of nitrogen among three major input rivers (Changjiang river, Jialingjiang river and Wujiang river) were studied.

Photo-induced toxicity of four polycyclic aromatic hydrocarbons, singly and in combination, to the marine diatom Phaeodactylum tricornutum.

Polycyclic aromatic hydrocarbons (PAHs) enter the aquatic environment by various routes and are usually found as mixtures in the water. Many studies have shown that solar ultraviolet (UV) radiation can greatly enhance the toxicity of some PAHs to a variety of marine species. In the present study, we tested the phototoxicity of four PAHs with simple structures, both alone and in binary combinations, to a species of marine diatom, Phaeodactylum tricornutum, in the laboratory.

[Historical evolvement trends of nutrients in waters of Bohai Bay from 1985 to 2003].

The local condition and the historical evolvement trend of nutrient elements were studied by the collection and analysis of the local investigation and the historical data. The surface seawaters are under the bad nitrogen contaminative conditions. Beitang and Dagu estuary are the main contaminative sources of inorganic nitrogen and phosphorus.

Heavy metal pollution in tidal zones of Bohai Bay using the dated sediment cores.

Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship among the contents of heavy metals, the contents of geochemical elements (Fe, Al and Mn) and the size of grain. The dominating contaminative elements in tidal sediments of Bohai Bay are Pb, Zn and Cd.

[Contaminative features of heavy metals for tidal sediment cores in Tianjin Bohai Bay].

Three sediment cores were collected in Nov. of 2003 from Dagu estuary to Qikou estuary. The grain size, TOC and heavy metal contents of core sediments were analyzed in order to study the geochemical characteristics, contamination features and the spatial and vertical distribution characters for heavy metals of tidal zones in Bohai Bay.

[Dynamic analysis of land use and land coverage in mid-eastern China during 1988-2000].

Using remote sensing (RS) and geographic information system (GIS) technologies and based on the documentary and field sampling data, this paper constructed and analyzed the 1988 and 2000 landscape maps of mid-eastern China. The mapping area of mid-eastern China was about 2.87 x 10(6) km2.