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101.
Long-term biological data supported by physicochemical parameters were evaluated to investigate the biodiversity of the Golden Horn Estuary from the past to the present. Limited observations dating back to 60 years ago indicated the existence of a diverse community in this small estuary. Unfortunately, in parallel with the increase in unplanned settlements and industry around the Golden Horn, pollution stress increased since the 1960s. Preliminary studies in the 1990s indicated survival of only a couple of pollution-resistant species, in the relatively cleaner lower estuary. Following the intensification of rehabilitation studies in 1998 and particularly after the opening of the floating bridge at the mid estuary; a remarkable day-by-day recovery in marine life has begun with the improving water quality. Nutrient concentrations decreased markedly; while water clarity significantly increased. Fecal coliform values decreased 10(3) fold. Phytoplankton composition changed and dense blooms of eukaryotic phytoplankters frequently occurred. Hydrogen sulfide almost completely disappeared even during the warmest periods of the year and dissolved oxygen concentrations increased. All results clearly depicted that the Golden Horn ecosystem shifted to eutrophic conditions from an anoxic environment. SCUBA dives in 2002, documented the level of diversification of life in the Golden Horn. All appropriate substratums were intensely covered by macrobenthic forms until the Halic Bridge and filter feeders dominated the plankton-rich ecosystem. Achieving the diversity of 1940s is not possible since the Black and Marmara seas, influencing water quality of the Golden Horn, are also suffering from anthropogenic impacts and are far less diverse than their rich diversity in 1940s. However, the Golden Horn is a good example that even the most polluted ecosystems can recover when appropriate measures are taken. 相似文献
102.
Yoshida A Nomura H Toyoda K Nishino T Seo Y Yamada M Nishimura M Wada M Okamoto K Shibata A Takada H Kogure K Ohwada K 《Marine pollution bulletin》2006,52(1):89-95
Microbial responses to the addition of oil with or without a chemical dispersant were examined in mesocosm and microcosm experiments by using denaturing gradient gel electrophoresis of bacterial ribosomal DNA and direct cell counting. When a water-soluble fraction of oil was added to seawater, increases in cell density were observed in the first 24h, followed by a decrease in abundance and a change in bacterial species composition. After addition of an oil-dispersant mixture, increases in cell density and changes in community structure coincided, and the amount of bacteria remained high. These phenomena also occurred in response to addition of only dispersant. Our results suggest that the chemical dispersant may be used as a nutrient source by some bacterial groups and may directly or indirectly prevent the growth of other bacterial groups. 相似文献
103.
104.
The geology of the Hsiwan coal field has been studied by Dr. Yoh of theGeological Survey of Kwangtung and Kwangsi and Messrs. Meng and Chang ofthe Geological Institute of the Academia Sinica. All these authors assigned aLower Carboniferous age to the coal-bearing series. Their grounds are probably 相似文献
105.
As a pioneer worker in almost every phase of the Chinese geology,the late Dr. V. K. Ting was also a pioneer and enthusiastic worker inthe geology of the Western Hills. It was due to his noble effort andsupervision that the first systematic investigation of 1916 was carried out 相似文献
106.
Y. AKASEGAWA 《地质学报》1926,5(2):135-140
In attempting to gain some notion as to the constitution of different types of coal of North China and their correlation, I have adopted at this initial stage two methods: One is the process of microscopic examination by 相似文献
107.
Important notice to members:- All members are earnestly requested to send to the Secretary of the Society any change of address. The 相似文献
108.
INTRODUCTION. The upper Cambrian of Fengtien was studied by Dr. Andersson whomade the following section and kindly permitted me to use it. (Fig. 1) Theupper Cambrian rest disconformably upon the pre-Cambrian rocks, which areof Sinian age. Upwards it is succeeded probably with a disconformity bythe Ordovician. 相似文献
109.
The Cambrian of China is developed in Yunnan, Shantung, Chihliand Manchuria. The first collection of Cambrian fossils was made by VonRichthofen and described by Dames and Kayser. Dames studied thetrilobites and Kayser described the brachiopods. 相似文献
110.
G.Y.Chang. 《地理学报》1935,(3)
(1) Cartography (2) Geophysics (3) Physiography (4) Climatology (5) Hydrography (6) Oceanography 相似文献