Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles

The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin are expressed in mammalian brains.This has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small animals.Understanding this issue is critical for elucidating the in vivo roles of PINK1 and Parkin.Recently,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate brain.In the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate brain.We found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey brains.PINK1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable distribution.Immunofluorescent double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial stress.These findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage.

A Study of the Distribution and Accumulation of Major Nutrient Elements in Different Densities of Eucalyptus grandis

This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that： （1） The distribution of ma- jor nutrient element contents in various organs of the E. grandis with the 2 densi- ties was nearly the same, and the ranked order was leaf〉tree trunk〉branch or branchlet〉fruit〉bark. （2） From the distribution of nutrient elements and organic mat- ter in the trunk, P, K, Mg and Ca contents presented basically a trend of increasing with the trunk height increasing. And the organic matter content increased with the trunk height increasing in the low density stand, while the result was opposite in the high density stand. Furthermore, N content increased with the trunk height increas- ing in the low density stand, but the content in the high density stand exhibited a trend of decreasing at first, increasing then and increasing at the last. （3） From the distribution of biomass, the ranked order was tree trunk〉bark or branch〉branchlet〉 leaf〉fruit. And （4） The accumulated amounts of major nutrient elements in various organs under the 2 stand densities was nearly same. Ca content was the highest in the 2 kinds of plantations, followed by N, K, Mg and P contents. Ca content was 601.78 kg/hm2 in the low density stand and 1 204. 43 kg/hm2 in the high density stand.

Distribution patterns of vegetation biomass and nutrients bio-cycle in alpine tundra ecosystem on Changbai Mountains,Northeast China

A study was conducted to test the correlation between biomass and elevation and the differences in concentration and storks of nutrients among five vegetation types （Felsenmeer alpine tundra vegetation-FA, Lithic alpine tundra vegetation-LA, Typical alpine tundra vegetation-TA, Meadow alpine tundra vegetation-MA, and Swamp alpine tundra vegetation-SA） on alpine tundra of Changbai Mountains, Jilin Province, China in growing seasons of 2003, 2004 and 2005. The biomass of 43 mono-species and soil nutrients in alpine tundra ecosystem were also investigated. Dominant species from Ericaceae （such as Rhododendron chrysanthum and Vaccinium jliginosum var. alpinum） were taken to analyze organ biomass distribution. Result showed that the biomass and elevation had a significant correlation （Biomass-237.3 in（Elevation） ＋494.36; R^2=0.8092; P〈0.05）. No significant differences were found in phosphorus and sulphur concentrations of roots, stems and leaves among the five vegetation types. There were significant differences in nitrogen and phosphorus stocks of roots, stems and leaves and in sulphur stock of stems and leaves among TA, MA, and SA vegetation types （p〈0.05）. The nutrient stock of five vegetations was averagely 72.46 kg.hm^-2, of which N, P, S were 48.55, 10.33 and 13.61 kg·hm^-2, respectively. Soil N and S concentrations in meadow alpine tundra soil type was significantly higher than those in other four soil types （Cold desert alpine tundra soil, Lithic alpine tundra soil, Peat alpine tundra soil, and Gray alpine tundra soil）. Phosphorous concentration in SA type was higher （p〈0.05） than in other types. Soil nutrient stock （0-20cm） was averagely 39.59 t.hm^-2, of which N, P, S were 23.74, 5.86, 9.99 t·hm^-2, respectively.

Distribution of Nutrients in Arable Land Soil of Western Hainan

[Objective] This study aimed to reveal distribution characteristics of soil nutrients in tropical farmland, thereby providing a reference for cropland management and balanced fertilization in the tropical area. [Method] Combining field survey and laboratory analysis, distribution status of nutrients in arable land of Baisha Li Autonomous County of Hainan Province was investigated. [Result] The soil in Baisha Li Autonomous County was acidic in overall with average pH value of 5.0. it had medium organic matter level （average of 19.3 g/kg） and rich alkali-hydrolyzable nitrogen content, but was lack of available phosphorus and available potassium. The spatial distribution of available nitrogen, available phosphorus and available potassi- um in the soil was uneven. The spatial distribution of soil nutrients was mainly related to soil parent materials of the investigated area and pH value of the investigated soil. [Conclusion] According to the distribution characteristics of nutrients in the soil, awareness of land use and land maintenance should be strengthened, application amount of organic fertilizers should be increased, chemical fertilizers should be applied rationally, and fertilization structure should be optimized in the future.

Spatial Distribution of Soil Total Nutrients of Farmland in Liaoning Province

[Objective]The aim was to reveal the spatial distribution characteristics of total nutrients in soil and provide a theoretical basis for farmland management and improvement of crop yield. [Method]GIS technique was used to analyze the spatial distribution characteristics of total C,total N,total P and total K for different soil layers in Liaoning Province. [Result]The results showed that the content of total C,total N,total P decrease from east to west,but the content of total K was high in north district of Liaoning Province. The content of total C,total N,total P and total K was higher in soil surface （0-20 cm） than the lower （20-40 cm）. Total K varied less with soil depth,and its mean content was respectively 17.64 g/kg and 17.08 g/kg for soil surface and soil lower layer. [Conclusion]The results of the distribution of soil total nutrients in different soil layers supplied a theory basis for farmland management.

Responses of Picoplankton to Nutrient Perturbation in the South China Sea, with Special Reference to the Coast-wards Distribution of Prochlorococcus

Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosphorus- (P), iron- (Fe), and cobalt- (Co) enriched incubations in the South China Sea in November 1997. Variations in abundance of the 4 groups of microorganism and cellular pigment content of the autotrophs during incubation were followed by flow-cytometric measurements for seven days. During the incubation, Syn and Euk showed a relatively higher demand on Fe and N, while Pro required higher levels of Co and P. The Fe was inadequate for all the organisms in the deep euphotic zone (75 m) of the study area. The experimental results also implied that biological interaction among the organisms played a role in the community structure shift during the incubation. It seemed that besides the effects of temperature, there are some other physical and chemical limitations as well as impacts from biological interactions on Pro distribution in coast waters.

Distribution and Accumulation of Nutrient Elements in Organic Tissue of Eucalyptus grandis Saplings

The biomass, macroelements （N, P, K, Ca, Mg） and microelements （Fe, Zn） contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of nutrient elements varied greatly in different organs. Total contents of macroelements N, P, K, Ca and Mg in1a-3a E. grandis were distributed in the order of stem phloem, leaves 〉 branch- es, roots 〉 stem xylem. Accumulated amount of macroelements in 1a-3a E. grandis were in the order of leaves 〉 branches 〉 stem phloem 〉 roots or stem xylem 〉 stem xylem or roots. Accumulated amount law of nutrient elements was not affected by the plant age. Microelements Fe and Zn were mainly concentrated in the leaves and roots. The accumulation of macroelements was in the order of Ca 〉 N 〉 K 〉 Mg 〉 P; and the microelements was in the order of Fe 〉 Zn. Accumulated amounts of microelements in 1a-3a E. grandis were 12.45 136.19 and 420.23 g per plants, respectively. Among the annual net accumulated amount of nutrient ele- ments per plant in 1a-3a E. grandis, Ca element was the maximum, N and K ele- ments took the second and third places. Mg element was relatively small and P el- ement was the minimum.

On Spatial Variability and Distribution of Soil Nutrients in Different Nitraria tangutorum Bobr.Populations in Tsaidam Basin

In this paper,six important distribution areas of Nitraria tangutorum Bobr.in Tsaidam Basin were selected as research objects,to study spatial variability and distribution of soil nutrients in different N.tangutorum populations and analyze the relationship between soil nutrient contents and geographical location,by measuring soil pH and the contents of organic matter（OM）,total nitrogen（N）,total phosphorus（P）,total potassium（K）,hydrolysis N,available P and available K in soils.Results showed that：（1） soil nutrient contents among different populations showed significant spatial variability,and soil depth had a significant effect on soil nutrients contents,but the variation rules were not obvious.（2）Average pH and average contents of OM,total N,total P,total K,hydrolysis N,available P and available K in soils with different depths（0-15,15-30,30-45 cm） varied in the range of 8.37-9.21,3.34-20.68,0.18-1.21,0.35-0.75,16.12-22.04,5.13-553.28,1.10-52.54 and 103.83-562.28 mg/kg,respectively.（3） The analysis results of correlation between average values of pH and contents of nutrient indexes in soils with different depths（0-15,15-30,30-45 cm） showed that the correlation of these indexes were different.（4）OM and total N contents in soils with different depths（0-15,15-30,30-45 cm） all had a significant positive correlation with latitude and negative correlation with longitude and altitude,and the correlation of available P and available K contents in surface soils（0-15 cm） with latitude,longitude and altitude were significant positive,significant negative and significant negative,respectively;moreover,longitude and latitude also showed a significant impact on soil available K contents with the depth of 30-45 cm.In addition,comprehensive analysis result of nutrient contents showed that N.tangutorum populations in Huaitou Tala Town had the highest fertility,and the fertility levels of N.tangutorum populations in Chaka Town and Wulan Keke Town were relatively lower.

Distribution of Main Nutrients in Seedlings of Umbrella Bamboo (Fargesia murielae) at Its Native Home in Central China

[Objective] The paper was to study the distribution of main nutrients in seedlings of umbrella bamboo (Fargesia murielae) in Shennongjia National Nature Reserve. [Method] The study was conducted in Liangfengya of Shennongjia National Nature Reserve. In the field investigation, six clumps of umbrella bamboo grown independently were randomly selected and sampled. The total nitrogen, total phosphorus and total potassium of umbrella bamboo were detected by regular plant analysis method. The age classes of bamboo seedlings were ascertained by age grade backtracking method. [Result] In different organs, N, P, K contents in branches and leaves were significantly higher that than in stems. Along age grades, N and P contents performed "M" shape in branches and leaves, while K content approximately performed as normal distribution. [Conclusion] The nutrients distribution pattern of these seedlings is likely formed by its nutrition mechanism which allocates nutrients according to different needs or by external interference of environmental features. However, the specific causes still need further investigation.

Impact of ice-snow damage on nutrient distribution of a Cunninghamia lanceolata woodland

During January to February in 2008,severe ice-snows occurred on 2.09×10^6 km^2 of south China and caused tremendous damage to the forests.Stem damage and crown debris input from the ice-snow in a Cunninghamia lanceolata stand in northern Guangdong Province,China,were investigated to determine the extent of ice-snow damage to trees and the nutrient distribution characteristics on woodland.Icicles were produced on branches and leaves of the C.lanceolata trees by sleets,resulting in all live trees were damaged by stem breakage.A strong positive correlation was found between the broken position of trees and diameter at breast height（DBH）.Nutrient concentrations varied according to components of crown debris.Total nutrient concentration graded in the following order：leaves 〉stembark 〉branches 〉stemwood.Crown debris input from ice-snows was 19.11 t·ha^-2,and branches,stemwood,leaves and stembark accounted for 37%,28%,27% and 8%,respectively.Nutrient distributions between components of crown debris differed drastically in 2008.The contribution of leaves to total nutrient accumulation of crown debris was 70%,whereas branches,stemwood and stembark contributed 13%,7% and 10%,respectively.Accumulations of N,P and K by the woodland were 105 067.9 t·ha^-2 in 2008,and the nutrients of crown debris,litter and the stand soil accounted for 0.18%,0.03% and 99.79%,respectively.The order of nutrient accumulation in leaves,branches,stembark,stemwood of crown debris and litter was N〉K〉P,but the nutrients stored in the soil were in the order of K 〉N 〉P.The N and P concentrations of litter in 2009 were greater than those in 2008,whereas its K concentration was smaller than that of the latter.N and P concentrations of stemwood and stembark in 2009 were slightly greater than those in 2009,whereas their K concentration was smaller than the latter.The N and P accumulations of stemwood and stembark of crown debris in 2009 were close to those in 2008,whereas their K accumulation was slightly smaller than the latter.The N,P and K accumulations of litter in 2009 was greater than those in 2008.

Effects of Primary and Secondary Trunk Girdling on the Status and Distribution Regularity of Nutrients in Grape

Objective] The study aimed to investigate the effects of primary and sec-ondary trunk girdling on the status and distribution regularity of nutrients in grape. [Method] Using grape cultivar ‘Rose Honey’ as the experimental material, the ef-fects of primary and secondary trunk girdling on carbon and nitrogen nutrition, min-eral nutrition and nutrient distribution regularity in leaves and branches above the girdling wound and roots below the girdling wound were analyzed. [Result] Girdling could significantly increase non-structural carbohydrate content （such as soluble sugar and starch） in branches above the girdling wound, reduce soluble protein and total nitrogen contents, and significantly improve C/N ratio. Specifical y, the highest C/N ratio in primary girdling group and secondary girdling group was 9.04 and 5.35, respectively, but C/N ratio in control group was only 4.89 in the same period. Girdling not only significantly decreased the content of non-structural carbohydrates （such as soluble sugar and starch） in roots, but also significantly declined soluble protein and total nitrogen content, which also reduced C/N ratio in various degrees. Specifical y, the lowest C/N ratio in primary girdling group and secondary girdling group was 1.16 and 3.06, respectively, while that in control group was 3.15 in the same period. ln addition, primary girdling exerted much greater effects on carbon and nitrogen nutrition than secondary girdling. Moreover, girdling significantly de-creased the contents of phosphorus, potassium, ferrum and copper in grape leaves, branches and roots. Specifical y, primary girdling exerted greater effects on ferrum and copper contents in leaves and branches. The contents of ferrum and copper in the first batch of samples exhibited significant differences between primary girdling group and control group： ferrum content in leaves was 75.05 μg/g DW in primary girdling group and that in control group was 85.29 μg/g DW; ferrum content in branches was 76.45 ？g/g DW in primary girdling group and copper content was 7.82 μg/g DW, while ferrum and copper contents in control group were 95.96 and 10.74 μg/g DW, respectively. [Conclusion] This study provided the basis for accu-rately regulating tree nutrition and ensuring safe and effective use of girdling tech-nique in ‘Rose Honey’ production.

Effects of Three-dimensional Structure of Vegetation on Particle Size Distribution and Nutrient Content of Water-eroded Red Soil

Based on the vertical stratification type of vegetation in the 48 plots （15m×15 m） in Hetian Town, Changting County, Fujian Province, this study was conduct ed to determine the overall vegetation fractional coverage （VFC）, litter thickness, soi particle size distribution and nutrient content at different vertical level, analyze the correlations between vegetation characters and soil properties, and compare the dif ferences in the VFC, litter thickness, soil particle size distribution and nutrient con- tent among different erosion degrees and vertical structure types. The result., showed that the VFC and litter thickness were all negatively related to erosion de gree; they were positively related to soil organic matter content, total nitrogen con- tent and total phosphorus content, but not significantly correlated with soil tota potassium content. When the VFC was higher than 50% and litter thickness wa.＇ higher than 20 ram, the water and soil could be effectively conserved; and the plan litter showed better water and soil conservation effect than the upper vegetation o~ canopy layer. In the vertical structure types of different vegetations, the forest-shrub grass, forest-shrub, shrub-grass and pure grass all could promote vegetation growth improve soil structure and maintain soil fertility.

Biomass production,nutrient cycling and distribution in age-sequence Chinese fir(Cunninghamia lanceolate)plantations in subtropical China

Biomass production and nutrient （N, P, K, Ca and Mg） accumulation, distribution and cycling were quantified in young, mature and over-mature （10-, 22-, and 34-year old） Chinese fir [Cunninghamia lanceolate （Lamb.） Hook] plantations in southern China. Total stand biomass of young, mature and over-mature stands was 38, 104 and 138 t ha-1 respectively. Biomass production increased significantly with age. Stem wood represented the highest percentage of stand biomass, accounting for 41, 55 and 63 % in the young, mature and over-mature plan- tations respectively. Nutrients concentration was highest in live needles and branches, and lowest in stem wood. The plantations accumulated more N, followed by K, Ca, Mg, and P. Nutrient return amount, nutrient utilization effi- ciency, nutrient turnover time, the ratio of nutrient return and uptake increased with stand age, which implies that young Chinese fir deplete soil nutrients to maintain growth, and efficiently utilize nutrients to decrease dependence on soil nutrients as they age. Harvesting young Chinese fir plantations would therefore lead to high nutrient loss, but prolonging the rotation length could improve soil recovery, and help sustain productivity in the long-term. Improved nutrient return through litterfall as stands get older may also be beneficial to nutrient pool recovery.

The Distribution Characteristics of Soil pH Values of Tobacco-growing Areas in Dali City and Its Correlation with Soil Nutrients

[Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in Dali City were analyzed.[Results] The results showed that average pH value of tobacco-planting soil in Dali City was 6.52, soil samples which suited for flue-cured tobacco cultivation accounted for 72.09% of total soil samples. In four soil types of tobacco-growing areas, the pH values in a descending order were as follows： alluvial soil〉 paddy soil 〉purple soil〉 red soil. At the altitude range of 1 780-2 200 m, soil pH values showed a gradual decreasing trend. The average contents of soil organic matters were relatively abundant and generally suited for high-quality tobacco cultivation; the average contents of soil alkali-hydrolyzable nitrogen, available phosphorus, exchangeable calcium and exchangeable magnesium were generally at medium and abundant level, however,their rations under the medium level in some tobacco-growing areas were 6.98%,11.63%, 2.33% and 4.65%, respectively; moreover, soil with lower available potassium contents occupied a large proportion, namely 58.14%. [Conclusion] Soil pH values had significant correlation with exchangeable magnesium and exchangeable magnesium, however, they had no significant correlation with other soil nutrients.

Distribution of nutrients and eutrophication assessment in the Bohai Sea of China

Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/PO4-P was much higher than the Redfield Ratio （16：1）. Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard （GB 3097-1997） for DIN and only 3.9% for PO4-R The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.

Spatial Distribution of Soil Organic Matter and Nutrients in the Pear Orchard Under Clean and Sod Cultivation Models

The soil organic matter and nutrients are fundamental for the sustainability of pear production, but little is known about the spatial distribution of soil organic matter and nutrients in a pear orchard. With the soil of the pear （cv. Dangshansu on P.betulifolia Bunge. rootstock） orchard under clean and sod cultivation models as test materials, the experiment was conducted to evaluate spatial variability of soil organic matter （SOM）, total nitrogen （STN）, total phosphorus （STP）, total potassium （STK）, available nitrogen （SAN）, and available potassium （SAK） in and between rows at different soil depths （0-60 cm）. The SOM, STN, STP, STK, SAN and SAK of the different soil layers under the two tillage models were different in the vertical direction. The SOM, STN, STP and SAN in the 0-20 cm soil layer were higher than those in the 20-40 and 40- 60 cm soil layers. The STK of 40-60 cm soil layer was higher than that in the 0-20 and 20-40 cm soil layers. The STK increased with the depth of soil in the vertical direction in the clean cultivated pear orchard. Variability of the SOM, STN, STP, STK, SAN and SAK of sample sites in between rows of the same soil layer was found in the pear orchard soil in the horizontal direction under clean and sod cultivation management systems, except that STK of all sites did not show the difference in identical soil layers in the pear orchard under clean cultivation. The sod cultivation model improved the SOM, STN, and STK in the 0-20 cm soil layer in the pear orchard, and the three components increased by 12.8, 12.7 and 7.3% compared to clean cultivation, respectively. The results can be applicable to plan collection of orchard soil samples, assess orchard soil quality, and improve orchard soil management practices.

Preliminary study on the distribution of nutrients, organic matter, trace metals in sea surface microlayer in Xiamen Bay and Jiulong Estuary

The enrichment of nutrients (Noa-, Noa-, PO43-), suspended particles, organic matter (POC, PON,DOC) , and trace metals (Cu, Ni, Cd) was determined in the sea surface microlayer of Xiamen Bay and Jiulong Estuary. The mean enrichment factors ([Xi]microlayer/[Xi ]15cm in depth) mostly ranged between 1 . 0 and 2. 0. The dissolved forms were the major forms of the components measured, the enrichment of dissolved organic matter and suspended particles could lead to the changes in the total amount and speciation of nutrients and trace metals. No correlation was observed between sample concentrations, speciation, enrichment factors and sample locations. However, some evidence shows that these parameters are correlated with sea state, indicating the complexity and dynamic nature of the sea surface microlayer.

Effect of subsoil tillage depth on nutrient accumulation, root distribution, and grain yield in spring maize

A four-year field experiment was conducted to investigate the effect of subsoiling depth on root morphology, nitrogen(N), phosphorus(P), and potassium(K) uptake, and grain yield of spring maize. The results indicated that subsoil tillage promoted root development,increased nutrient accumulation, and increased yield. Compared with conventional soil management(CK), root length, root surface area, and root dry weight at 0–80 cm soil depth under subsoil tillage to 30 cm(T1) and subsoil tillage to 50 cm(T2) were significantly increased, especially the proportions of roots in deeper soil. Root length, surface area, and dry weight differed significantly among three treatments in the order of T2 > T1 > CK at the12-leaf and early filling stages. The range of variation of root diameter in different soil layers in T2 treatment was the smallest, suggesting that roots were more likely to grow downwards with deeper subsoil tillage in soil. The accumulation of N, P, and K in subsoil tillage treatment was significantly increased, but the proportions of kernel and straw were different. In a comparison of T1 with T2, the grain accumulated more N and P, while K accumulation in kernel and straw varied in different years. Grain yield and biomass were increased by 12.8% and 14.6% on average in subsoil tillage treatments compared to conventional soil treatment. Although no significant differences between different subsoil tillage depths were observed for nutrient accumulation and grain yield, lodging resistance of plants was significantly improved in subsoil tillage to 50 cm, a characteristic that favors a high and stable yield under extreme environments.

Nutrient composition and distributions in coastal waters impacted by the Changjiang plume

Four cruises were conducted during 2002--2003 in the Changjiang Estuary and adjacent coastal areas. The data presented show a clear coast to open sea gradient in nutrients related to the river inputs. Maximum values of chlorophyll a were typically observed at intermediate salinities at surface water and coincided with non-conservative decreases in nutrients along the salinity gradient, indicating that removal of nutrients was related to phytoplankton uptake. The seasonal variations of nutrient concentrations were just opposite to those of chlorophyll a, indicating that the seasonal variations of nutrients were mainly controlled by phytoplankton uptake, whereas riverine inputs merely weakened or balanced its extent. During the estuarine mixing, phosphate demonstrated some remobilization during all the four cruises; whereas both conservative and non-conservative behaviors for dissolved inorganic nitrogen and silicate were observed in the study area, indicating that both biotic and abiotic events may affect their behaviors during the estuarine mixing. Under the influence of freshwater inputs with high value of ratio of nitrogen to phosphorus, the estuarine and coastal waters impacted by the Changjiang plume were high （ 〉 30） in ratio of nitrogen to phosphorus, but rates of primary production were apparently not constrained by any kind of nutrient elements. However, the low （ 〈 1 ） ratio of silicate to nitrogen in most of the study area might be linked with the rapidly increasing frequency of harmful algal bloom （HAB） incidents in recent years in the coastal waters impacted by the Changjiang plume.

Transport and distribution of nutrients in anchovy spawning ground to the southern waters of Shandong Peninsula

The distribution of nutrients and the effect of side transport of nutrients on anchovy spawning ground to the southern waters of Shandong Peninsula are discussed based on the data collected in June 2000, May and June 2001. The coastal current and upwelling are the main physical processes of nutrient transport to the southern waters of Shandong Peninsula. The concentrations of nutrients, Chl-a, the density of anchovy eggs, larva and juvenile fish increase obviously where they are greatly affected by these processes, while the contents of nutrients and Chl-a, the density of anchovy eggs, larva and juvenile fish decrease significantly where these processes diminish or disappear. The investigation suggest that the side transport of nutrients by Lubei (North Shandong) coastal current in the northern area causes the Chl-a content to be high and dense anchovy eggs, larva and juvenile fish to be dense in the coastal area of the Chengshan Cape. In the southern area, the riverine input from Subei irrigation ditch with high content of nutrients inshore and upwelling in the western edge of the Huanghai Sea Cold Water offshore should be responsible for high Chl-a concentration and dense anchovy eggs, larva and juvenile fish. It is possible that these processes of nutrient transport have controlled the anchovy spawning ground to the southern waters of Shandong Peninsula.