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CHUMS洽洽鸟中国首家直营体验店开幕
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《中国眼镜科技杂志》 2014年第4期214-214,共1页
2013年12月20日下午,来自美国犹如他州的户外时尚潮牌CHUMS洽洽鸟在上海美罗城“欧美风情街”趣味登场。说到CHUMS洽洽鸟,不得不提到它畅销世界的眼镜绳。
关键词 眼镜行业 CHUMS “中国首家直体验店” 眼镜品种 市场
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Factors Influencing Large-scale Operation of Large Grain Farmers in Northeast China
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作者 刘文新 何秀丽 《Agricultural Science & Technology》 CAS 2017年第12期2622-2627,2632,共7页
With the grain yield accounting for 20% of the whole country, the north- east China is a strategic region for ensuring national grain security and also a most centralized region of large grain farmers. Through a sampl... With the grain yield accounting for 20% of the whole country, the north- east China is a strategic region for ensuring national grain security and also a most centralized region of large grain farmers. Through a sampling survey of large grain farmers in 15 counties and cities of northeast China, with the aid of SPSS and AMOS software, using multiple regression analysis and structural equation modeling, this paper made a quantitative analysis on the influence of the subjective and ob- jective factors of large grain farmers on their large-scale management. The results showed that the age structure, educational level, family operating capital, yield ex- pectation and protective farming awareness of large grain farmers are the positive factors influencing their large scale operation due to agricultural subsidy policy. By comparison, the number of agricultural machinery and equipment owned by family, regional labor force, expectation for future income, and expectation for contractual scale become negative factors influencing large-scale operation of large grain farm- ers because of agricultural policies. When the future expectation, self conditions, family endowment, and operation conditions of large grain farmers increase one unit, their large scale operation motivation will increase by 0.692, 0.689, 0.487 and 0.363 units respectively. Thus, increasing the future expectation and self conditions of large grain farmers is a key factor for promoting large scale operation of farmland. 展开更多
关键词 Large grain farmers Large-scale operation Motivation Northeast China
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Nutrients distribution and trophic status assessment in the northern Beibu Gulf, China 被引量:17
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作者 赖俊翔 姜发军 +3 位作者 柯珂 许铭本 雷富 陈波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1128-1144,共17页
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore wat... Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf. 展开更多
关键词 nutrient EUTROPHICATION Trophic index (TRIX) Assessment of Estuarine Trophic Status(ASSETS) Beibu Gulf Guangxi Province
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Nutrient and chlorophyll a anomaly in red-tide periods of 2003-2008 in Sishili Bay, China 被引量:8
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作者 郝彦菊 唐丹玲 +1 位作者 喻龙 邢前国 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期664-673,共10页
Sishili Bay is the most important aquiculture and tourism area for the city of Yantai, China; however, red tides occurred frequently and have caused huge economic losses in this bay in recent years. To gain a better u... Sishili Bay is the most important aquiculture and tourism area for the city of Yantai, China; however, red tides occurred frequently and have caused huge economic losses in this bay in recent years. To gain a better understanding of the local ecological environments in the bay, we conducted this research between 2003 and 2008 to analyze variations in nutrients and chlorophyll (chl-a) during high frequency red tide period (May to September). The results show that the chl-a concentration increased from 2.70 in 2003 to 7.26 mg/m3 in 2008, while the concentration of total inorganic nitrogen (TIN) and silicate (SiO3-Si) increased lineally from 5.18 and 1.45 pmol/L in 2003 to 18.57 and 9.52 pmol/L in 2008, respectively, and the annual phosphate (PO4-P) varied between 0.15 and 0.46 μmol/L. Special attention was given to a red tide in August 2007 occurred when water temperature was high and nutrient concentrations increased sharply because of a heavy rainfall. Overall, the results show the P limitation in Sishili Bay, and reveal that red tides were caused by eutrophication from terrestrial inputs and local warm weather, particularly during rainy periods. Therefore, to control red tide, greater efforts should be made to reduce sewage discharges into Sishili Bay, particularly during rainfall seasons. 展开更多
关键词 CHL-A TIN PO4-P red tide frequency Sishili Bay
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Spatial Variability of Nutrient Properties in Black Soil of Northeast China 被引量:124
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作者 ZHANG Xing-Yi SUI Yue-Yu +2 位作者 ZHANG Xu-Dong MENG Kai S. J. HERBERT 《Pedosphere》 SCIE CAS CSCD 2007年第1期19-29,共11页
A total of 1400 soil samples from the plow layer (0-20 cm) at an approximate interval of 5 km were collected in the autumn of 2002 over the entire black soil arable crops region to determine the spatial variability ... A total of 1400 soil samples from the plow layer (0-20 cm) at an approximate interval of 5 km were collected in the autumn of 2002 over the entire black soil arable crops region to determine the spatial variability of seven variables, such as total organic matter content (OMC), total N, total P, total K, alkali-dissolvable N (AN), available P (AP) and available K (AK), with classical statistics and geostatistical analysis across the entire black soil area in Northeast China. In nonsampled areas ordinary kriging was utilized for interpolation of estimated nutrient determinations. Classical statistics revealed highly significant (P ≤ 0.01) correlations with all seven of the soil properties, except for OMC with AP and total K with AK. In addition, using coefficients of variation, all soil properties, except for total K, were moderately variable. A geostatistical analysis indicated that structural factors, such as parent material, terrain, and water table, were the main causes of the spatial correlations. Strong spatial correlations were noted with OMC, total N, total P, AN, and AP, while they were moderate for total K and AK. The effective spatial autocorrelation of OMC, total N, total P, and AN ranged from 1 037 to 1353 km, whereas the ranges of total K, AP, and AK were only from 6 to 138 km. The fit of the experimental scmi-variograms to the theoretical models indicated that except for AN, kriging could successfully interpolate other six variables. Thns, the geostatistical method used on a large scale could accurately evaluate the spatial variability of most black soil nutrient properties in Northeast China. 展开更多
关键词 black soil China geostatistics analysis soil survey spatial variability
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Sustainable Nutrient Management in Chinese Agriculture: Challenges and Perspective 被引量:34
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作者 GAO Chao SUN Bo ZHANG Tao-Lin 《Pedosphere》 SCIE CAS CSCD 2006年第2期253-263,共11页
China has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance t... China has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented. 展开更多
关键词 China food security nutrient management soil fertility water quality
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Restoration in northern Lake Gehu, a eutrophic lake in China 被引量:4
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作者 吴晓东 李文朝 +3 位作者 潘继征 马书占 陈丙法 何尚卫 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1417-1431,共15页
Lake Gehu is a severely eutrophic lake in southeast China. A series of restoration measures have been implemented since 2009 in northern Lake Gehu. This study compared aquatic plants, water quality, sediment, and phyt... Lake Gehu is a severely eutrophic lake in southeast China. A series of restoration measures have been implemented since 2009 in northern Lake Gehu. This study compared aquatic plants, water quality, sediment, and phytoplankton between restoration and control areas to investigate the effect of restoration measures. The results demonstrated that aquatic macrophyte coverage increased from 0% to 10.6%; mean TP, TN, and CODm concentrations decreased by 50.0%, 42.4%, and 40.8%, respectively, compared with those before the measures were carried out; the mean Secchi depth (SD) increased to 42.5 cm, which is 1.4 times higher than that before restoration; the mean euphotic depth (Zeu) in the summer increased from 91 to 130 cm; the mean chl a concentration decreased from 34.8 to 20.2 μg/L, compared with that before restoration; the Shannon-Wiener index of phytoplankton increased by 28.7%. The mean TP and TN concentrations in sediments decreased by 63.8% and 52.4%, respectively, compared with that before dredging. These results indicate that the restoration in northern Lake Gehu was effective. To complete the transformation from an algae- to a macrophyte-stable state within the region, further measures must be adopted. This restoration of a eutrophic lake can serve as a reference for similar eutrophic lakes. 展开更多
关键词 Lake Gehu EUTROPHICATION local areas RESTORATION
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Influencing Factors of Chinese Telecom Operators' EVA 被引量:2
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作者 Fu Sibao Li Zheng Xu Qionglai 《China Communications》 SCIE CSCD 2012年第2期72-78,共7页
To analyze the positive influencing factors of Chinese telecom operators' EVA(Economic Value Added),this paper selects fifteen indicators based on the enterprise features of telecom operators and telecommunication... To analyze the positive influencing factors of Chinese telecom operators' EVA(Economic Value Added),this paper selects fifteen indicators based on the enterprise features of telecom operators and telecommunications industry characteristics,and then classifies these indicators into the following factors:operation scale,profitability,solvency and asset management ability by factor analysis.This paper also gives the priorities of these four factors by regression analysis,of which the operation scale is the most important factor.The research results point out a clear method for the telecom operatorsto increase their EVA in order to meet the performance appraisal from State-owned Assets Supervision and Administration Commission of the State Council. 展开更多
关键词 telecom operators influencing factors EVA
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Silicon limitation on primary production and its destiny in Jiaozhou Bay, China Ⅷ: The variation of atmospheric carbon caused by both phytoplankton and human 被引量:1
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作者 杨东方 苗振清 +2 位作者 石强 陈豫 陈国光 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期416-425,共10页
Statistical analysis on data collected in the Jiaozhou Bay (Shandong, China) from May 1991 to February 1994 and those collected in Hawaii from March 1958 to December 2007 shows dynamic and cyclic changes in atmospheri... Statistical analysis on data collected in the Jiaozhou Bay (Shandong, China) from May 1991 to February 1994 and those collected in Hawaii from March 1958 to December 2007 shows dynamic and cyclic changes in atmospheric carbon in the Northern Pacific Ocean (NPO), as well as the variation in space-time distribution of phytoplankton primary production and atmospheric carbon in the study regions. The study indicates that the human beings have imposed an important impact on the changing trends of the atmospheric carbon. Primary production in the Jiaozhou Bay presents a good example in this regard. In this paper, dynamic models of the atmospheric carbon in the NPO, the cyclic variations in the atmospheric carbon, and primary production in the Jiaozhou Bay are studied with simulation curves presented. A set of equations were established that able to calculate the rate and acceleration of increasing carbon discharged anthropologically into the atmosphere and the conversion rate of phytoplankton to atmospheric carbon. Our calculation shows that the amount of atmospheric carbon absorbed by one unit of primary production in the Jiaozhou Bay is (3.21–9.74)×10-9/(mgC·m-2d-1), and the amount of primary production consumed by a unit of atmospheric carbon is 102.66–311.52 (mgC·m-2d-1/10-6). Therefore, we consider that the variation of atmospheric carbon is a dynamic process controlled by the increase of carbon compound and its cyclic variation, and those from anthropologic discharge, and phytoplankton growth. 展开更多
关键词 atmospheric carbon carbon conversion human beings PHYTOPLANKTON Jiaozhou Bay Hawaii
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Two new species of Sellaphora(Bacillariophyta) from a deep oligotrophic plateau lake,Lake Fuxian in subtropical China 被引量:1
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作者 李艳玲 METZELTIN Ditmar 龚志军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1160-1165,共6页
We describe two new species of Sellaphora from Lake Fuxian, Ytmnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. ... We describe two new species of Sellaphora from Lake Fuxian, Ytmnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. The primary features of S. yunnanens& are: elliptical to linear-elliptical valves with broadly rounded ends, straight filiform raphe, almost straight central endings and small, slightly expanding central pores, small central area, symmetrical or slightly asymmetrical central nodule. The primary features of S. sinensis are: elliptical valves, obtusely rounded ends, similar raphe and axial area, transapically less expanded central area, larger, elliptical central nodule. We compare these species to those of a similar shape and morphology. 展开更多
关键词 China DIATOM Lake Fuxian new species Sellaphora Yunnan Plateau
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Preference of the Herbivorous Marine Teleost Siganus canaliculatus for Different Macroalgae 被引量:2
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作者 YOU Cuihong ZENG Fangui +1 位作者 WANG Shuqi LI Yuanyou 《Journal of Ocean University of China》 SCIE CAS 2014年第3期516-522,共7页
The decomposition of a large amount of unexploited macroalgal resource along the coast of China often results in heavy environmental pollution. In order to pave a way of using macroalgae as the dietary ingredient of r... The decomposition of a large amount of unexploited macroalgal resource along the coast of China often results in heavy environmental pollution. In order to pave a way of using macroalgae as the dietary ingredient of rabbitfish Siganus canaliculatus, one of a few farmed herbivorous marine teleosts in China, its preference(feeding selectivity) for different macroalgae was determined in this study. Seven seaweed species abundantly inhabiting the coast of east Guangdong Province were exposed simultaneously to rabbitfish juveniles in laboratory(multiple-choice feeding) with their content and absolute intake assayed. It was found that the most preferred algae were Ulva prolifera, Gracilaria lemaneiformis and Chaetomorpha linum, less preferred algae were U. pertusa and Porphyra haitanensis, and least preferred ones were Sargassum fusiforme and Corallina sessilis. Such an order did not change when one to four relatively preferred seaweeds were removed. The preferred seaweeds were richer in protein and soluble sugar thus higher in energy than the least preferred. In addition, this fish was found to favor filamentous and flat algae rather than calcified ones. Accordingly, the richness of nutrients and morphological characteristics determined the preference of S. canaliculatus for tested macroalgae. 展开更多
关键词 Siganus canaliculatus feeding preference MACROALGAE NUTRIENT
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Research on the Competitive Power of the Industrial Clusters in China 被引量:1
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作者 Zhang Zhiyuan Li Feng Qi Fei 《Ecological Economy》 2005年第3期79-83,共5页
Industrial clusters have been an important phenomenon of the global economy. The most important reason for its becoming the focus of people's attention and the popular mode of industry programming is continuous and p... Industrial clusters have been an important phenomenon of the global economy. The most important reason for its becoming the focus of people's attention and the popular mode of industry programming is continuous and powerful competitiveness ,The article analyzes this competitiveness, and points out some problems of China's industrial clusters, which directly affects its current competitiveness and further development. Finally, we propose stone specific measures of those problems. 展开更多
关键词 industrial clusters competitive advantage collective efficiently competitive power
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Roof structure theory and support resistance determination of longwall face in shallow seam 被引量:2
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作者 黄庆享 《Journal of Coal Science & Engineering(China)》 2003年第2期21-24,共4页
This paper presents the structure models founded in shallow seam, the roof asymmetry arch with three articulations in roof first weighting and the step voussoir beam in roof periodic weighting. These structure models ... This paper presents the structure models founded in shallow seam, the roof asymmetry arch with three articulations in roof first weighting and the step voussoir beam in roof periodic weighting. These structure models are differ from classic theory, it establishes the new roof control theory of instability structure roof, especially in shallow seam. Based on the new roof structure theory, the support working state of "given sliding load" is put forward, and the factor of load transmitting is introduced to determine the load on roof structure. Therefore, the proper and accurate calculating methods of support resistance are established. Based on this, the dynamic structure theory in shallow seam could be predicted. 展开更多
关键词 shallow seam roof structure support resistance load transmitting
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Relationship between environmental factors and plankton in the Bayuquan Port, Liaodong Bay,China:a five-year study 被引量:7
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作者 宋伦 杨国军 +1 位作者 王年斌 鲁晓倩 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期654-671,共18页
To understand the relationship between the plankton community and environmental factor and water quality in the Bayuquan Port of Liaodong Bay, China, and investigations were carried ou during six dif ferent periods(Ap... To understand the relationship between the plankton community and environmental factor and water quality in the Bayuquan Port of Liaodong Bay, China, and investigations were carried ou during six dif ferent periods(April 2009, April 2010, October 2011, April 2012, October 2012, and Apri 2013). This area was characterized by high levels of nutrient and suspended solids(SPS) during surve periods, and eutrophication led to the occurrence of red tides in April and October 2012 and April 2013 Our analyses revealed that the plankton communities of Bayuquan Port lacked stability and were af fecte seriously by external disturbance(e.g., oceanographic engineering and river runof f). Our data indicate tha oil, dissolved inorganic nitrogen(DIN), SPS, and chlorophyll a(Chl- a) were key factors that regulated th phytoplankton and zooplankton communities. The partial redundancy analysis(partial RDA) suggested tha oil and SPS were the most important environmental variables af fecting the phytoplankton community i April 2010 and 2012, whereas DIN concentration played a governing role in zooplankton dynamics. Oi and Chl-a concentrations af fected signifi cantly the zooplankton community in October 2012. Therefore, th plankton communities could refl ect both dynamic changes in coastal environmental factors and the ongoin eutrophication process caused by anthropogenic activities in this area. 展开更多
关键词 PHYTOPLANKTON ZOOPLANKTON ABC curve environmental variables ecological stability Bayuquan Port
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Response of rotifer community to environmental changes in five shallow lakes in the middle reach of Changjiang River, China 被引量:1
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作者 都雪 冯伟松 +4 位作者 李为 叶少文 刘家寿 张堂林 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1083-1091,共9页
We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic s... We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang (Yangtze) River in summer and autumn 2010. These five lakes differed in trophic status and rotifer community structure. Twenty-nine rotifer species were collected, of which Keratella cochlearis, Polyarthra dolichoptera, and Trichocerca elongate were dominant. The mean density, Shannon-Wiener diversity, and equitability among the five lakes differed significantly (P〈0.05). The mean rotifer density was positively correlated with trophic state. The diversity was higher in lakes with high macrophyte coverage. The composition of rotifer species was closely associated with the trophic gradient. Five environmental variables, Secchi depth, conductivity, TN, NHa-N, and TP, significantly affected the composition of rotifer species. Keratella quadrata, Brachionus calyciflorus, and B. forficula were more common in eutrophic conditions. Our results suggest that eutrophication has a significant influence on the rotifer community structure and highlight the potential for using rotifer community structure as an indicator of trophic status in subtropical lakes. 展开更多
关键词 ROTIFER environmental variables shallow lakes EUTROPHICATION
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Nutrient Structure of the Taiwan Warm Current and Estimation of Vertical Nutrient Fluxes in Upwelling Areas in the East China Sea in Summer 被引量:5
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作者 SHI Xiaoyong LI Hongmei WANG Hao 《Journal of Ocean University of China》 SCIE CAS 2014年第4期613-620,共8页
Based on field data for nutrients collected on the continental shelf of the East China Sea(ECS) during summer 2006, the structure and variations of nutrients in every water mass related to the Taiwan Warm Current(TWC)... Based on field data for nutrients collected on the continental shelf of the East China Sea(ECS) during summer 2006, the structure and variations of nutrients in every water mass related to the Taiwan Warm Current(TWC) were analyzed. The supplementary effect of nutrient of upwelling on harmful algal blooms(HABs) in the ECS was also estimated, based on upwelling data. Then the maintenance contribution of nutrient of upwelling to HABs was assessed. The results showed that N/P ratio is fairly low in both surface and deep layers of the TWC, which possibly controls nutrient structure of the HABs-frequently-occuring areas. In upwelling areas, the rate of phosphate(PO4-P) uptake exceeds that of nitrate(NO3-N) of the TWC. The TWC may relieve PO4-P limitation during the process of HABs. Furthermore, upwelling plays an important role in providing nutrients to HABs. After estimating nutrient fluxes(NO3-N, PO4-P, Si O3-Si) in the upwelling areas along a typical section(S07), the results showed that the nutrient uptake rate is the greatest at 10-20 m below euphotic zone, sustaining the ongoing presence of HABs. The uptake rate of PO4-P is the highest among dissolved inorganic nutrients. Therefore, upwelling is most likely the main source of PO4-P supply to HABs. 展开更多
关键词 nutrient structure FLUX Taiwan Warm Current UPWELLING East China Sea
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A niche model to predict Microcystis bloom decline in Chaohu Lake, China 被引量:2
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作者 汪志聪 李钟杰 李敦海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第4期587-594,共8页
Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simp... Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simple and effective mathematical-ecological model to evaluate the growth status and predict the population dynamics of Microcystis blooms. In this study, phytoplankton were collected and identified from 8 sampling sites in Chaohu Lake every month from July to October, 2010. The niche breadth and niche overlap of common species were calculated using standard equations, and the potential relative growth rates of Microcystis were calculated as a weighted-value of niche overlap. In July, the potential relative growth rate was 2.79 (a.u., arbitrary units) but then rapidly declined in the following months to -3.99 a.u. in September. A significant correlation (R=0.998, P<0.01) was found in the model between the net-increase in biomass of Microcystis in the field and the predicted values calculated by the niche model, we concluded that the niche model is suitable for forecasting the dynamics of Microcystis blooms. Redundancy analysis indicated that decreases in water temperature, dissolved oxygen and total dissolved phosphorus might be major factors underlying bloom decline. Based on the theory of community succession being caused by resource competition, the growth and decline of blooms can be predicted from a community structure. This may provide a basis for early warning and control of algal blooms. 展开更多
关键词 Microcystis bloom niche breadth niche overlap predictive model Chaohu Lake
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Influence of ginseng cultivation under larch plantations on plant diversity and soil properties in Liaoning Province,Northeast China 被引量:1
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作者 LIU Wei-wei LIU Mou-cheng +2 位作者 LI Wen-hua ZENG Fan-shun QU Yi 《Journal of Mountain Science》 SCIE CSCD 2016年第9期1598-1608,共11页
Currently, transforming the mode of forest management and developing multiple forest management practices are actively encouraged in China. As one forest management type, ginseng cultivation under larch plantations ha... Currently, transforming the mode of forest management and developing multiple forest management practices are actively encouraged in China. As one forest management type, ginseng cultivation under larch plantations has been developed significantly in the east of Liaoning Province. However, research on the influence of the ecological environment for this mode of production is still deficient. Based on this, our study compares the plant diversity and soil properties in the ginseng cultivation under larch plantations(LG) with larch plantations(LP) and natural secondary forests(SF). First, we randomly selected three plots for each of the three stand types which have similar stand characteristics; then, we carried out a plant diversity survey and soil sampling in each of the nine plots. The results show that no significant difference was found in plant diversity between LG and LP, but theevenness of herbs was significantly lower in LG than LP. No obvious changes in soil physical properties were found in LG, but a significant decrease in most of the soil nutrient content was presented in LG. Furthermore, we found a correlation between plant diversity(H') and soil properties in the three kinds of stand types, especially between herbaceous plant diversity and soil properties. We conclude that ginseng cultivation under larch plantations has no obvious effect on plant diversity, except the herbaceous evenness. Soil fertility can be depleted significantly in LG, but physical structures are not affected. Moreover, maintaining the diversity of herbaceous plants and controlling the density of ginseng cultivation in LG by farmers are important for the ecological environment. Based on this study and its good comprehensive benefits and with the support of policy, we think this forest management type should be promoted moderately in the region. 展开更多
关键词 Forest management Ginseng cultivation Larch plantations Secondary forests Plant diversity Soil properties Changbai Mountain
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Phosphorus Speciation in Wetland Sediments of Zhujiang (Pearl) River Estuary,China 被引量:11
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作者 WANG Lili YE Mei +2 位作者 LI Qusheng ZOU Hang ZHOU Yongsheng 《Chinese Geographical Science》 SCIE CSCD 2013年第5期574-583,共10页
Phosphorus fractions and adsorption-release characteristics of sediments in the Zhujiang (Pearl) River estuary wetland were investigated. Results showed that the total phosphorus (TP) content in surface sediments ... Phosphorus fractions and adsorption-release characteristics of sediments in the Zhujiang (Pearl) River estuary wetland were investigated. Results showed that the total phosphorus (TP) content in surface sediments ranged from 648.9 mg/kg to 1064.0 mg/kg; inorganic phosphorus (IP) was the major fraction of TP and ranged from 422.5 mg/kg to 643.9 mg/kg. Among the inorganic phosphorus, the main fractions were phosphorus bound to A1 and Fe (Fe/A1-P), and calcium-bound phosphorus (Ca-P), accounting for 23%-42% and 21%-67% of IP, respectively. The vertical distribution of TP contents were significantly positive correlated with organic phosphorus (Org-P) and Fe/A1-P contents. The bio-available phosphorus contents in vertical sediments varied from 128.6 mg/kg to 442.9 mg/kg, mainly existed in Fe-AI/P fraction, and increased from the bottom to top sediments. The transport of phosphorus in sediment-water in- terface was controlled by the soil characteristics. The active Fe and A1 content was considered as the main factor that determines adsorp- tion capacity in vegetated marsh wetland. The P buffering capacity of the sediments in vegetated marsh wetland was greater than that in mudflat wetland. The potential risk of eutrophication in the study area is high. Reducing terrestrial phosphorus discharge and preventing the sediment Fe/A1-P release to the interstitial water are the possible solutions to reduce the risk of eutrophication in estuary wetlands, and planting vegetation in estuary wetland can also reduce the release of phosphorus in surface sediment. 展开更多
关键词 estuary wetland PHOSPHORUS FRACTION ADSORPTION-DESORPTION
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Changes in the small-jellyfish community in recent decades in Jiaozhou Bay, China 被引量:3
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作者 孙松 李颖虹 孙晓霞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第4期507-518,共12页
We used long term monitoring data to evaluate changes in abundance and species dominance of small-jellyfish (collected with zooplankton net whose bell diameter was less than 5 cm) between 1991 and 2009 in the Jiaozhou... We used long term monitoring data to evaluate changes in abundance and species dominance of small-jellyfish (collected with zooplankton net whose bell diameter was less than 5 cm) between 1991 and 2009 in the Jiaozhou Bay, China. Zooplankton samples were vertically towed with conical plankton net from near-bottom to surface, identified microscopically, and mapped in time-space using Grapher 7.0 and Surfer 8.0. Results show that the abundance of small-jellyfish throughout the bay had been increasing during 2001-2009 on average of 15.2 ind./m 3 , almost 5 times higher than that between 1991 and 2000. The occurrence of peak abundance shifted from spring to summer after 2000, and two peaks appeared in spring and summer, respectively, after 2005. Both the abundance and the frequency of blooms of small-jellyfish increased after 2000 in the bay. In addition, the biodiversity of jellyfish has increased significantly in recent years with a change in dominant species. Several new dominant species appeared after 2000, including Rathkae octopunctata in winter, Phialidium hemisphaericum in spring, summer, and autumn, Phialucium carolinae in spring, and Pleurobrachia globosa in summer and autumn, while some previous dominant species throughout the 1990s (Eirene ceylonensis, Zanclea costata, Lovenella assimilis, and Muggiaea atlantica) were no longer dominant after 2000. The abundance of small-jellyfish was positively correlated with the density of dinoflagellates, and the abundance of zooplankton. We believe that the changes in smalljellyfish abundance and species composition were the result of eutrophication, aquaculture and coastal construction activities around the bay. Concurrently, seawater warming and salinity decrease in recent decades promoted the growth and reproduction of small-jellyfish in the bay. 展开更多
关键词 JELLYFISH ABUNDANCE species composition Jiaozhou Bay
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