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1.
In this paper,the aquatic chemical characteristics in the Hangzhou Bay,Xiangshan Bay and Leqing Bay along the coastal region of Zhejiang Province are discussed . Results show that the seasonal variations of chemical elements are obvious. The distribution of silicate in Hangzhou Bay and contents of dissolved oxygen and nutrient in the Xiangshan Bay are found to be unusual in winter. Correlations among the elements are complex. The content of nutrient in the Hangzhou Bay is higher than that in Xiangshan Bay and the content of nutrient in the Xiangshan Bay is higher than that in the Leqing Bay . The variation of the ratio of N/P is obvious. This reflects the aquatic chemical characteristics in the bay. Finally, this paper also discusses the reason why the aquatic chemical characteristics in the bays are unusual.  相似文献   

2.
According to two cruises investigation information in summer and winter during 1998 and1999, the phosphorous concentration distribution and changes of summer and winter were discussed pri-marily in the South China Sea. The results show that the phosphate concentration of surface seawater insummer is distinctly lower than that in winter, averaging 0.04 μmol/dm3 in summer and 0.35 μmol/dm3 in winter. The organic phosphorous concentration of surface seawater in summer is higher than thatin winter, averaging 0.12μmol/dm3 in summer and 0.04 μmol/dm3 in winter respectively. The season-al changes of total phosphorus are similar to phosphate, averaging 0.22 μmol/dm3 in summer and 0.61μmol/dm3 in winter respectively. In vertical direction, phosphate, TDP and TP content are the lowestin upper 50 m water column, and increase in linearity rapidly with water depth, increasing slowly under500 m, reach to maximum about 1 000 m, then decrease slightly with water depth increasing. The ver-tical distribution is typical in summer, and there is small dispersed for phosphorus concentration for thesame depth of different stations. However, in winter there is a large disperse for phosphate, TDP andTP, specifically for phosphate at 200 m at which the concentration is maximum. This result indicatesthat there are large differences in hydrology and biology conditions that affect largely the chemical envi-ronment of the South China Sea. The organic phosphorus is the predominant in surface seawater of theSouth China Sea, but the inorganic phosphorus is the predominant in layers below depth of 150 m. Theorganic phosphorus concentration in deep water usually decreases with water depth increasing. The or-ganic phosphorus in summer is remarkably more than that in winter because of the strong biology activi-ties in summer.  相似文献   

3.
The physical and chemical features of Pupu Springs (40 51’ S, 172° 46’ E), near Takaka, the largest cold springs in New Zealand and one of the largest in the world, were investigated by scuba diving. The springs have a maximum depth of 6.9 m and a mosaic of substrate types (bedrock, boulders, and gravel). The temperature of the springs water is constant at 11.7°C, water velocities are generally moderate to very strong (25–100 cm.s‐1), and average water discharge is about 9.6 m3.s‐1. Mean holding time for water in the springs is 4.4 min. The water is extremely clear, with a vertical extinction coefficient (log10) of 0.09. The springs water flows from an artesian basin in Arthur Marble and is low in dissolved oxygen. The water is rich in calcium (64 g.m‐3), with a high specific conductivity (65 mS.m‐1). Information on water temperature, discharge, and chemistry is provided for five other cold springs in New Zealand: Hamurana Springs, Rotorua; Otangaroa Springs, near Putaruru; Three Springs, near Fairlie; Western Springs, Auckland; and a spring at Lake Hayes, Queenstown.  相似文献   

4.
The five chemical bound forms of Fe, Al and Mn in sediments in the main channel of the Zhujiang River.and its estuary, namely, exchangeable, carbonic, oxidative, organic and residual (in crystal) forms, were determined. The method of sequential extraction was used for separating the five bound forms.The main chemical form of the three elements in the sediments of the Zhujiang River and its estuarine zone is the residual one. The exchangeable form exists only in a small fraction.Correlationships between the concentration of a certain form of heavy metals and Eh. pH and salinity were discussed. The principles of geochemistry are used to explain the mechanism of heavy metal transport in the river.It was also found that the distribution rule of the chemical forms of Fe, Al and Mn in sediments in the lower reaches of the Zhujiang River was similar to the one in the lower reaches of the Yamaska River.  相似文献   

5.
We study the space-and-time variations of the delivery of fluxes of 26 elements (Na, K, Rb, Cs, Cu, Ag, Au, Ca, Sr, Ba, Zn, Cd, Hg, Hf, Ta, As, Sb, Cr, Se, Mo, W, Mn, Br, Fe, Co and Ni) with atmospheric precipitations to the sea surface in the regions of Sevastopol and the South Coast of Crimea. It is established A series of general regularities of the delivery of the sum of these elements and their soluble and insoluble forms. We also give the characteristics of their space-time variability.  相似文献   

6.
There is a low nutrient level in the Aoshan Bay. In June 1999, the chemical adjustmentand control experiment was made in the Aoshan Bay. Following tracts investigation was carried out before the experiment and on the 1st, 2nd, 4th, 5th, 6th and 45th day/after the experiment. While the variance of amount of phytoplankton, the replacement of superior species and the species composition of phytoplankton were researched. The results show that the amount of phytoplankton in the Aoshan Bay rises gradually after the experiment. Ceratium macroceros Cleve of pyrophyta was the dominant species before the experiment, its dominant index was 37.7％. Six days after the experiment, its dominant index dropped to 17.6％ . Meanwhile the dominant index of Asterionella japanics Cleve rose from 7.1％ to 39.2％ , it became the first dominant species. Forty-five days after the experiment, the amount of phytoplankton in the Aoshan Bay was 5.15 to 137.32 times more than that in 1997.  相似文献   

7.
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8.
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9.
Summary

Lake Pupuke, situated in the North Island of New Zealand near Auckland (Latitude 36° 53'S, Longitude 174° 52'E), is a small, circular body of water (maximum width 1.2 km, maximum depth 55 m). From November 1966 to November 1967 observations on its physico‐chemical factors were made twice monthly.

The range of temperatures in the year was 12.0–24.2°c at the surface and 11.3–14.5°c at 40 m. A thermocline farmed between early October and early January, when it became strongly developed at about 17 m and persisted until late April. Between early May and late June the stratification was breaking down and between mid July and mid September the lake was isothermal.

The values for light transmitted per metre through the water were high from mid August to mid December (53–76% per metre), very low from mid December until mid February (23–49% per metre), high in March (75% per metre) and relatively constant over the winter months (53–64% per metre). The amount of light transmitted depended closely on the density of phytoplankton. Changes in the depth at which a Secchi disc disappeared paralleled the light transmission values, and the mean Secchi depth was 2.2 m, range 1.0–5.2 m.

Oxygen concentrations down to 30 m were highest at all depths from mid November to early January (112–134% saturation). From early January to late April oxygen was strongly stratified (epilimnion 55–100% saturation, hypolimnion 24–77% saturation). During winter oxygen values gradually increased at all depths.

The range of pH was 7.8–9.5 units at the surface and 7.8–8.6 units at 30 m. From early January to late April pH values were strongly stratified but from mid July to mid August they were nearly uniform. The range of alkalinity (mainly HCO3 ? ions) was 76.0–80.8 ppm CaCO3 and values showed stratification in summer. Carbonate ion was present from early October to mid June, but free carbon dioxide was only found in trace amounts.

The range of nitrate ion concentrations was 0.05–0.31 ppm; nitrate became obviously depleted in summer. Only one nitrite value was significant, 0.25 ppm. other nitrite values never exceeded 0.10 ppm. The concentration of ammoniacal nitrogen built up to a summer maximum of 0.95 ppm in the hypolimnion (annual range 0–0.95 ppm); values for albuminoid ammonia (0.016–1.03 ppm of nitrogen) varied with the quantity of living matter present.

The annual mean for total ion concentration (3.30 meq./1) was high and the order of ions was Na+>Mg2+>Ca2+>K+ and HCO3 ?>CI?>SO4 2?. Such dissolved salts may have arrived as airborne particles, dissolved in rain, or as sea spray.  相似文献   

10.
Lake Ototoa is a warm monomictic lake at 36° 31’ S, 174° 14'E. During a year's study (March 1969‐March 1970), the lake became thermally stratified in November, the metalimnion being between depths of 12 m and 16 m. Surface temperatures ranged between 10.2°c (in August) and 25.2°c (in late January), and bottom temperatures between 9.7°c and 17.5°c. The annual heat budget was calculated to be 642 354 KJ.m‐2 (15 500 cal.cm‐2) and the work of the wind in distributing the heat income 1.730 KJ.m‐2 (1766 g.cm.cm‐2). Secchi disc transparencies ranged between 5 m and 9.2 m (mean 7.07 m) and were greatest in the summer. Light transmission per metre was also high, ranging between 61% and 87%. Surface waters were normally supersaturated with oxygen, but during summer stratification oxygen concentrations in the bottom waters dropped to a minimum of 2.3 mg.litre‐2 and a positive heterograde distribution of oxygen with depth was found. The oxygen deficit was 0.015 mg.cm‐2.day‐1 and showed the lake to be oligotrophic. Mean surface pH was 7.82, and the ionic composition of the waters was similar to that of other small New Zealand and Australian lakes located near the sea. Compared with other New Zealand lakes PO4‐P concentrations (range 1.00–10.20 μg.litre‐1) were low and NO3—N concentrations (range 0.12–0.60 mg.litre‐1) high.  相似文献   

11.
We find a diverse but increasing amount of evidence to suggest considerable dissolution of calcium carbonate, perhaps as much as 60–80%, in the upper 500–1000 m of the ocean, well above the chemical lysocline. The same biological processes that promote the rapid settling of carbonate particles (i.e. ingestion, digestion and egestion by zooplankton) as well as biologically mediated processes within flocculates and aggregates may be responsible – directly or indirectly – for much of this dissolution. The significance of shallow-water dissolution of carbonate particles necessitates further research into both its validity and, if true, specific causal mechanisms.  相似文献   

12.
In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People's Republic of China and Japan cooperative program, from July 23 to August 21, 1987. The concentration size distributions and composition of marine aerosols over the Kuroshio area are analyzed. Neutron activation analysis is used to determine the elemental composition of the aerosols. The authors also discuss some characteristics of marine aerosols relating to long-range transport of crustal and anthropogenic elements from the continent to the remote ocean. Analytical results indicate that elements Al, Fe, Sc and Sb over this area are obviously influenced by the continent of Asia, and the size distributions are changed after long-range transport. The concentration of large particles increase. The concentrations of the elements C1 and Na are closely related to ocean conditions; the source of the elements Cl an  相似文献   

13.
1Introduction Besidestheprecipitationandriverdischarges,the watersinthePacificOceanandtheAtlanticOceanare thesourcesoftheArcticOceanwater.TheAtlantic waterenterstheArcticOceanviatheFramStraitand theBarentsSea.Foritsdenserfeatureduetohigh salinity,mostofitsinkstothenorthofSvaldbardand circulatesinallthedeepbasinsintheArcticOcean, formingthedeepandbottomwatersoftheArcticO- cean(Aagaardetal.,1985;Rudelsetal.,1999).The BeringStraitistheonlychannelforthePacificwater toflowintotheArcticOce…  相似文献   

14.
The present paper deals with the ultrastructural changes of oocyte in the process of maturing in pen shell Atrinapectinata Linne. When it develops from the antecedent growth period to the accelerating growth period the annulate lamellae emerge, the RER better develop, the yolk granules with single and double layer membrane and are visible. In the well-developed mitochondria there is yolk stored. The Golgi vacuoles are brewing yolk granules. At the mature period the annulate lamellae and the Golgi bodies disappear, and there are only a few RER and mitochondria with poor cristae in the cytoplasm. All these might be well used for judging the maturity of the ootids in the process of the artificial propagation.  相似文献   

15.
1Introduction TheChangjiang(Yangtze)Riverdrainageba sinliesbetween25°and35°N,andbetween91°and122°E,withatotalareaof1.81×106km2anda populationof4×108.Itpassesthroughadensely populatedareawithwell developedindustryandag riculture,includingShanghai,the  相似文献   

16.
Respiration (=oxygen consumption) rates of 28 zooplankton species belonging to 10 taxa from 500 to 5,000?m depth of the western subarctic Pacific Ocean were determined as 0.027–0.44?μLO2 mg dry mass?1 h?1 at in situ temperatures (1.5–3?°C), which are 80?% lower than the rates of the epipelagic Antarctic zooplankton with similar body mass and at a comparable temperature. In terms of adjusted metabolic rate to 1?mg body N (AMR; μLO2?mg?N?0.8?h?1) at 1?°C, the present results (mean 1.66) fall well within the range (0.84–3.32) reported for copepods, chaetognaths, and mixed crustaceans from 500 to 7,000?m in the subarctic Pacific Ocean and Antarctic waters. Judging from their body C:N elemental ratios and ash-free dry mass (=organic matter) data, the major component of organic matter is deduced to be protein (C:N?=?3.4–8.1, by mass) for 19 out of 28 species and lipids (C:N?=?8.6–13.0) for the remaining 9 species.  相似文献   

17.
Oceanographical features on both sides of Balingtang Channel (17°55'-20°06'N,122°55'-126°57'E) were comprehensively investigated on board of R/V "Experiment 3" in June.1984.The present paper reports the chlorophyll data collected and primary productivity estimated there.Water samples were taken with a glass bottle of Model HQM1-2 at the depth of 0,10.25,50,75,100 and 150 m,separately.Chlorophyll was determined according to the spectrophotometry proposed by UNESCO(1966) and calculated with the trichromatic equations of Jeffrey-Humphrey(1975).Estimations of primary productivity were carried out using a simplified equation (Q=1.5) given by Cadée(1975).  相似文献   

18.
Oceanographical features on both sides of Balingtang Channel (17°55′-20°06′N, 122°55′-126°57′E) were comprehensively investigated on board of R/V "Experiment 3" in June. 1984. The pre-sent paper reports the chlorophyll data collected and primary productivity estimated there. Water sam-ples were taken with a glass bottle of Model HQM_(1-2)at the depth of 0, 10. 25, 50, 75, 100 and 150m, separately. Chlorophyll was determined according to the spectrophotometry proposed by UNESCO(1966) and calculated with the trichromatic equations of Jeffrey-Humphrey(1975). Estimations ofprimary productivity were carried out using a simplified equation (Q = 1.5) given by Cadee(1975).  相似文献   

19.
ＴｅｔｒａｐｌｏｉｄｉｎｄｕｃｅｄｂｙｐｈｙｓｉｃａｌａｎｄｃｈｅｍｉｃａｌｍｅｔｈｏｄｓｉｎＪｉｎｊｉａｎｇｏｙｓｔｅｒ（Ｃｒａｓｓｏｓｔｒｅａｒｉｖｕｌａｒｉｓ）￥ＲｏｎｇＳｈｏｕｂａｉ，ＳｈｉＳｈｕｍｅｉ，ＭｃＱｉｒｏｎｇ，ＬｉｕＳｈａｅｑｉｏ...  相似文献   

20.
I\TRODLCTIO\In ootal enviroaments, the degradation of sedimentaIy organic matter was the main pro-cess of the biQgaxhemistry cyclc of nutrients, which controlled not only the bury efficiency oforganic carbon but a1so the nutrients flux to overlylng water (Aller, l980). The rnain mecha-nism of whneralization of sediment was organic rnatter degradation such a-s biolOgic and redOxprocesses, these reactions oould convert sedirnentary organic rnatter into nutrients, then releaseto the intersti…  相似文献   

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