| Jiaozhou Bay is a typical semi-closed and shallow bay located in temperate zone which has been greatly affected by anthropogenic activities. Because it has a representative location and ecologic conditions to a certain extend explored and it combines with ambient society and economy to be a multiplex ecosystem, it is a perfect object to study the effects of human activities on marine environment. More and more attentions have been paid to the eutrophication research in recent years. The need for petroleum for the human living and production is increasing and it causes the petroleum hydrocarbon pollution inshore. In order to know the pollution status of petroleum hydrocarbon and the relations between it and the other environmental factors, the thesis gets the space-time distribution characteristic of the petroleum hydrocarbon and other environmental factors and also have made a analysis on the relations between petroleum hydrocarbon and other environmental factors based on the research and analysis on the data from May 2000 to October 2004. Here are the results:1. The concentration of the petroleum hydrocarbon in Jiaozhou Bay distributes from 30.2μg/L to 241μg/L, and the average is 43.2μg/L. The inspection rate is 100% and 43% exceeds the standard. Influenced by source and the wiping-off approach, the space-time distributing characteristic of the petroleum hydrocarbon in Jiaozhou Bay is as the follows: The concentrations in eastern and north-eastern areas are relatively higher, while the contents in central and north-western areas are quite lower. There is no distinct time distributing characteristic. The reasons why individual station have got high value at very few time are caused by the petroleum leakage and the sail drainage. Although being polluted by petroleum coming from several different origins, the pollution status of the petroleum in Jiaozhou Bay is not very serious, for most of the seawater is accord with the first-degree standard. It shows that there is a relatively higher environmentalcapacity in Jiaozhou Bay.2. The concentration of Chemical Oxygen Demand (COD) in Jiaozhou Bay ranges from 0.08-3.16mg/L. and the average is 1.33mg/L and is a little higher than the COD in the ocean water. The horizontal distributing characteristic are as the follows: The content in the eastern and north-eastern area is relatively higher, while the contents in the central and north-western area are relatively lower. It may be caused by river import. There is no distinct rule in the time distribution and the concentration lies on the importing source.3. By mensurating the dissolved inorganic phosphor and the total dissolved inorganic nitrogen in Jiaozhou Bay and with the analysis on space-time changing rule of the total inorganic nitrogen and the inorganic phosphor, it shows as follows: From the year of 2000 to 2004, the concentrations of the total dissolved inorganic nitrogen in Jiaozhou Bay range from 0.0128-4.776 μmol/L and the average is 0.6841 μmol/L, the concentrations of the dissolved inorganic phosphor in Jiaozhou Bay range from 0.002-0.312 μmol/L and the average is μ0.0196 mol/L. There is no distinct rule in the space-time distrabution. The N/P ratios in Jiaozhou Bay are very lower than that of the ocean water, they range from 1 to 1001 and the average is 99. It shows that the biology growth in Jiaozhou Bay is under the control of the phosphor, and it is also can be concluded from the concents of the inorganic phosphor in the whole Jiaozhou Bay seawater. The distributing status of the nutrients in Jiaozhou Bay may be caused by the special geographical position. The distribution of the nutrients is controlled by the land drainage, biology metabolism and the water blending process et al.4. From May 2000 to October 2004, the concentrations of the chlorophyll a in Jiaozhou Bay range from 0.44-34μg/L and the average is 4.52μg/L. The inspection rate is 100%. The horizontal distributing characteristic is as the follow: Because of the poor exchanging of the Jiao Zhou Bay seawater with the open sea, the phytoplankton accumulates in the Bay, and the chlorophyll a can not spread in time. There is a relatively higher value in the eastern and north-eastern area in Jiaozhou Bay. There is a rule in the time distribution as the follows: The odds that appear the highest value is relatively higher in the August of every year, while in the spring is lower and the fallis the lowest. The eutrophication in Jiaozhou Bay often occurs in summer (from June to August), while it is rare in spring. It leads to the chlorophyll a concentration is relatively higher in August. That is also the distinct characteristic of the water ecosystem in Jiaozhou Bay.5. With the analysis on the relations between petroleum hydrocarbon and the other environmental factors, it can be found that there is some relativity between the petroleum hydrocarbon and the other environmental factors. The relativity is negative between the petroleum and the dissolved oxygen (DO), while the positive with the others. The average correlation coefficient is as followings: petroleum hydrocarbon/COD, r=0.43; petroleum hydrocarbon/inorganic phosphor, r=0.42; petroleum hydrocarbon/total inorganic nitrogen, r=0.59; petroleum hydrocarbon/ chlorophyll a, r=0.44; petroleum hydrocarbon/DO. r=0.49; It is clear that the correlative coefficient are not very high, it shows that there is some relations between the environmental factors, but there is some independency between them.
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