Distribution of dissolved and particulate minor and major elements in the river and coastal environment of East Java during the Snellius-II expedition

The concentration and distribution of dissolved Cu, Zn, Cd, Ni, Pb and Fe, and Cu, Zn, Cd, Ni, Pb, Cr, Fe, Si, Ca, Mg, Mn and K in suspended matter have been determined in the rivers Porong and Solo and in Strait Madura (East Java), during the dry- and wet-monsoon periods. Based on element/Al ratios, the suspended matter supplied by each of the two rivers can be traced offshore. The main source of material supplied to the coastal area is the Solo river. The distribution of the trace-metal content in suspended matter collected in the rivers can be described as a mixture of metal-rich, organic-rich particles and a metal-poor, detrital fraction. Due to the presence of mud barriers at the river mouths, particles with high trace-element contents are trapped in the estuaries. Compared to European rivers the dissolved trace-metal concentrations in these rivers are relatively low. The dissolved concentrations of the different trace elements in Strait Madura show no uniform distribution pattern during the two sampling periods.     

Soft-bottom benthic community in the estuarine waters of East Java

During the Snellius-II Expedition, both in the period July–August and in the period November–December 1984, the structure of the macrobenthic communities in the estuaries of the rivers Porong, Wonokromo and Solo was investigated. The numerical densities of the benthic organisms (>0.5 mm) from the Porong, Wonokromo, and Bengawan Solo estuaries during the Snellius-II Expedition varied between 87 and 5787 ind·m⁻²; biomasses between 0.4 and 602 g DW·m⁻². The high numerical density (1573 ind·m⁻²) found at st.2 of the Porong estuary in period I (July–August 1984) was attributed to the dense population of the bivalve Varicorbula rotalis. Consequently a very high biomass (602 g DW·m⁻²) was measured at this station.The mollusc Theora lata and the polychaetes Ancistrosyllis parva, Nepthys dibranchis, Paraprionospio pinnata, and Sternaspis laevis occurred at almost every station during the investigation periods.Paraprionospio pinnata and Theora lata, which are considered indicator species of disharmonic environments, were found at almost every station of the study areas in both periods. Species diversity at all the stations was low, ranging form 0.1 to 1.6.     

Copper,zinc and cadmium in benthic organisms from the Java Sea and estuarine and coastal areas around East Java

A study was made of the concentrations of copper, zinc and cadmium in benthic organisms, representing the phyla Mollusca, Arthropoda, Echinodermata and Pisces, from the riverine and estuarine areas of the rivers Brantas and Solo (East Java) and the adjacent coastal area. Moreover, an assessment was made of the contamination of the benthic biota with these elements in the Java Sea and Bali Sea.Benthic organisms show a species-specific uptake pattern for each element. Compared to the same type of animals from estuaries and coastal areas in temperate regions of western Europe, the concentrations of cadmium are considerably higher, while copper and zinc concentrations are somewhat lower.There is no general trend in concentration levels of the metals in specimens from rivers, estuaries, coastal zone and open sea. In some groups of organisms (e.g. shrimp, starfish) the concentrations of copper and zinc are highest in specimens from rivers and estuaries. In contrast, cadmium concentration levels in e.g. crab, shrimp and squid are lowest in riverine and estuarine areas.Significant differences in metal concentrations in these organisms were found between the dry monsoon period (July, August) and the beginning of the wet monsoon (November, December).No relationship existed between the metal concentration of the organisms and the silt fraction of the sediment (grain size < 63 μm) or the bulk sediment.     

The determination of suspended metals in coastal waters by different sampling and processing techniques (filtration,centrifugation)

The concentrations, on a sediment weight basis, of several metals in coastal suspended matter show a marked dependence on the amount of particulate matter per litre. The effects of filtration and centrifugation are compared. The resulting data are interpreted in terms of varying contributions of larger and denser bottom derived particles with higher concentrations of K, Fe, Mn, and Al and of smaller and less dense, continuously suspended particles with higher concentrations of Cu, Cd, Pb and Zn. No dependence on size or density was found for Cr, Si, Mg and Ca.Filtration results in higher concentrations of Cu, Cd, Pb, and Zn. For the other elements, centrifugation results in concentrations that are at least similar to those in particulates obtained by filtration, or even larger for elements with relatively large difference between the concentrations in the different fractions, such as K. Leaching particulates, obtained by filtration and centrifugation, with 0.1 N HCl leads to differences in the leached fractions for Cd, Cr, K and Mg at lower suspended loads, and for Fe at higher loads, while no differences are observed for Cu, Pb, Zn, Si, Mn, Al and Ca.Accurate particulate metal concentration data were obtained by measuring in each individual sample, the amount of both metal and particulate matter. This results in more accurate data than can be obtained by measuring each of the properties in separate samples. Another source of errors is eliminated by analyzing the entire content of a sampler in stead of part of it, because of sample inhomogeneity introduced by settling of particles in the sampler.In order to get accurate sediment weight data at low suspended matter concentrations, sea salt was removed from the particulate matter by a rinsing procedure with distilled water. No loss of the metals investigated (Cu, Cd, Zn, Cr, Si, Fe, Mn, and Al) was evident with a possible exception for Cd.     

Heavy metals (Cu,Zn, Cd,Pb) in sediment of the Java sea,estuarine and coastal areas of East Java and some deep-sea areas

The concentrations of copper, zinc, cadmium and lead were measured in the bulk sediment and the silt fraction of the surface sediment (upper 2 cm) from the riverine and estuarine zones of the rivers Brantas and Solo and in the adjacent coastal areas around East Java. The levels of contamination of the sediments with heavy metals were also determined in the Java Sea, some sites in the Bali Sea and the Indian Ocean.The concentrations of the trace elements were consistently higher in the silt fraction than in the bulk sediment. Trace element levels were higher in riverine and estuarine sediments than in sediment from coastal waters and the Java Sea. Increased copper, zinc and cadmium concentrations were measured in surface sediment from deep-sea areas.There were no or only minor differences in the metal concentrations in the sediment (both bulk sediment and the silt fraction) between the dry and the wet monsoon.     

The partition of trace metals between dissolved and particulate phases in european coastal waters: A compilation of field data and comparison with laboratory studies

The recent literature on trace metal distributions in water and suspended particulates is examined and partition coefficients calculated. The extent to which this is possible is limited since most surveys do not determine trace metals in both phases and record the suspended solids loading.The results indicate that for most metals the partition coefficient is dependent on solids loading. This finding is in agreement with previous laboratory based experiments. Partition coefficients from the field are, however, generally greater than those obtained in laboratory experiments. Possible sources of difference between laboratory and field studies are discussed.It is concluded that in estuarine and coastal waters particle-water interactions are important and that studies which examine only one phase are unlikely to further our knowledge of trace metal behaviour in such environments.     

Nutritional status and pigment composition of phytoplankton during spring and summer Phaeocystis blooms in Dutch coastal waters (Marsdiep area)

The general nutritional status and pigment composition of the phytoplankton population during the 1991 spring and summer Phaeocystis blooms in Dutch coastal waters was analysed using the 480/665 nm absorption ratio of 90% acetone extracts as well as reverse-phase HPLC-pigment analysis. A 100% increase in this ratio was indicative of moderate nutrient deficiency at the end of the Phaeocystis spring bloom in the Marsdiep area. During the summer, nitrate was more likely to be the limiting nutrient than phosphate. Both physiological adaptation and species composition were found to influence the absorption ratio. Variations in the absorption ratio did not completely reflect the variations in fucoxanthin and chlorophyll a. Therefore it was concluded that besides nutrient limitation dynamics, the variable abundances of in particular chlorophyll-c3 containing species (such as Prymnesiophyceae) may effect the absorption ratio.     

The role of small,low density particles on the partition of selected PCB congeners between water and suspended matter (North Sea area)

The dissolved and particulate suspended concentrations of five PCB congeners (with 3–7 chlorine atoms) in the Southern Bight (North Sea) are interpreted in terms of an equilibrium partitioning model. K_d values for riverine/coastal samples generally increase with chlorine number of the congeners (K_d = 10⁴–10⁶). Values are more than an order of magnitude larger at the low suspended matter concentrations offshore (< 1 mg·dm⁻³). This is interpreted in terms of the presence of different SPM fractions with different contents of PCB: a fraction consisting of low size/density particles carrying high contents of PCBs, dominates at low SPM concentrations. The contribution of particulate forms to the total PCB concentration per unit volume may, therefore, be significant even at low SPM concentrations.     

Distribution,organic content and particle size of suspended matter in the north sea

Data on suspended matter concentrations and the organic content of the suspended matter for January 1980 showed a division in the North Sea between the southern North Sea (high suspended matter concentrations, but relatively low organic content) and the central and northern North Sea (low suspended matter concentrations, but relatively high organic content). The Skagerrak, which receives suspended matter from the southern as well as from the central and northern North Sea, took up an intermediate position.In summer suspended matter concentrations were lower than in winter but more variable, in concentration as well as in organic content, because of admixtures of particulate matter from primary production. On deposition of the suspended matter, a considerable part of the organic matter was apparently lost (in the order of 75% or more), resulting in low organic-matter concentrations of fine-grained bottom deposits.Particle-size distributions followed two main types: one (A) with a sharp peak at 30 to 100 μm, and one (B) bell-shaped with a peak at 5 to 15 μm. Type A occurred in deeper water and consisted of particles with a high organic-matter content, type B occurred in shallow areas and consisted of particles with a low organic-matter content. The suspended particles were mainly microflocs of mineral particles and organic matter. The mineral particles of both types were predominantly of 2 to 5 μm size, which was determined after oxidation of the organic matter. It is concluded that particles of type-B distributions are regularly exchanged with the bottom through deposition and resuspension, which results in low organic-matter contents and prevents the microflocs reaching large sizes. Paricles of type-A distributions, on the contrary, can reach much larger sizes, because mostly they remain in suspension and do not lose organic matter, so that they do not easily fall apart.     

Distribution and particle size of suspended matter in the Southern Bight of the North sea and the Eastern channel

The distribution of suspended matter content in the Southern Bight is related to the resultant current pattern. Suspended matter is concentrated in the coastal waters and high concentrations occur where resultant currents of different directions meet near to the large gyres off the Belgian-Dutch coast and off East Anglia. Suspended matter is chiefly supplied to the Southern Bight from the Channel through Strait Dover-Calais (at least 8 to 11.5 × 10⁶, probably 11.5 to 15 × 10⁶tons·a⁻¹. Other sources are the rivers that enter the Southern Bight (ca 2 × 10⁶ tons·a⁻¹), coastal erosion (ca 0.3 × 10⁶ tons·a⁻¹), erosion of the sea floor (in the order of several million tons·a⁻¹) and the atmosphere (ca 0.5 × 10⁶ tons·a⁻¹). Supply from primary production is small (less than 1 × 10⁶ tons·a⁻¹). Total supply of suspended matter to the Southern Bight is 17.5 to 21.5 × 10⁶ tons·a⁻¹. The concentration of suspended matter in the coastal waters is probably related to a shoreward displacement of bottom water.Particle size determinations were made (with a Coulter Counter) during the winter in the absence of living plankton. Measurements were made directly after sampling or within several hours. In the Belgian-Dutch Coastal Water particle size is somewhat finer than in Strait Dover-Calais and in the central part of the Southern Bight (the “Channel Water”). In the English Coastal Water particle size is more variable. The bulk of the suspended particles has a diameter of 5 to 20 μm but there is a variable admixture of particles of 1 to 3 μm. Most size distributions are a mixture of two log-normal distributions. In the Belgian-Dutch coastal water, in the eastern Channel and in Strait Dover-Calais regularly approximately log-normal distributions are present. The size distributions reflect the multiple origin of the suspended material and the variable conditions of deposition, resuspension and aggregation.     

Distribution and origin of polycyclic aromatic hydrocarbons in the sediments from Chongqing section of the Yangtze River

The analysis of PAHs in sediments of 12 sampling sites from Chongqing section of the Yangtze River shows that total PAHs concentration ranges from 0.64~3.98 μg/g in dry season and 0.85~4.63 μg/g in wet season,with the maximum content of phenanthrene accounting for 11%~27% of total PAHs. The 3~5 rings PAHs are dominant in sediment samples,while the content of PAHs with 2 and 6 benzene rings is small. Moreover,the compositions of PAHs are significantly different as they are taken from different sampling periods,releasing more 6-ring PAHs in rainy season. The combustion of fossil fuels and oil spillages of ships may be dominant sources in the study area and the degree of sediment contamination by PAHs is moderate in comparison with other internal and external sediments. However,fluorene and phenanthrene exceed the probable effect level (PEL),which might certain potential damage to the ecosystem in the studied area.     

河西走廊东部大风日数时空分布及其对沙尘天气的影响

为揭示大风日数的时空演变规律及其对沙尘天气的影响,更好地防御和减轻风沙灾害。笔者利用1971—2010年河西走廊东部4个气象站大风、沙尘暴、扬沙观测资料,采用气候统计学方法,对河西走廊东部大风日数时空演变及与沙尘暴和扬沙日数的关系进行分析。结果表明:近40年河西走廊东部年大风日数以10.77 d/10 a的速率显著减少;四季年大风日数亦均呈显著减少,递减率夏季最大,冬季最小;年、季节大风日数随年代增加呈减少趋势;大风日数春季最多,秋季最少,4月最多,9月最少。大风日数的空间分布与海拔高度、地形地貌有很大关系,高海拔山区大风日数最多,北部荒漠区以及浅山区较多,绿洲平原区最少。近40年河西走廊东部年沙尘暴和扬沙日数均显著减少。年大风日数与年沙尘暴和扬沙日数呈极显著正相关,其相关系数分别为0.878和0.888;大风日数随时间的变化对沙尘日数随时间的变化具有显著正作用,大风日数的减少可能是沙尘日数减少的主要原因之一。     

Chattonella and Fibrocapsa (Raphidophyceae): First observation of,potentially harmful,red tide organisms in Dutch coastal waters

Species of the potentially toxic and red-tide-forming marine-phytoplankton genera Chattonella and Fibrocapsa (Raphidophyceae) were observed for the first time in 1991 in samples taken in Dutch coastal waters; they were again recorded and enumerated in the following years. Chattonella spp. cell numbers varied with the season, with a maximum in May or June in the Dutch Wadden Sea. Cell numbers of Chattonella and F. japonica Toriumi et Takano were up to 6.0·10³ cells·dm⁻³ in the Dutch Wadden Sea, except at one station in June 1993 when over 10⁴ cells·dm⁻³ Chattonella were counted. In May 1993, a minor bloom (over 2.0·10⁵ cells·dm⁻³) was observed at a station in the southern central North Sea, 100 km northwest of the island of Terschelling. The potentially neurotoxic species Chattonella marina (Subrahmanyan) Hara et Chihara was identified and discriminated from morphologically related species within the class of Raphidophyceae by immunofluorescence. F. japonica could only be clearly identified in live samples; in fixed samples cell morphology was severely affected. The identification of this species was supported by the presence of mucocysts, structures that can be observed readily by optical and electron microscopy.     

Chemical and physiological changes of phytoplankton during the spring bloom,dominated by phaeocystis pouchetii (Haptophyceae): observations in Dutch coastal waters of the North Sea

During the spring bloom of phytoplankton in Dutch coastal waters of the North Sea the flux of ¹⁴C-labelled products into pools of protein, polysaccharides, small metabolic intermediates and lipids was studied. The molecular size distribution of extracellular products, amounting to 28% of the particulate production, was determined by gel filtration. Concentrations of protein and carbohydrates were determined in the same phytoplankton samples. At an early stage of the bloom protein synthesis and protein concentration dominated over carbohydrate synthesis and carbohydrate concentration, but after the peak of the bloom carbohydrates were the predominant photosynthetic endproduct. These observations have been compared to similar observations on unialgal cultures of Phaeocystis pouchetii. The influence of phosphate depletion on the extracellular release of organic compounds and the impact of the colonial growth form of Phaeocystis pouchetii on the distribution of intra- and extracellular labelled compounds are also discussed.     

Distribution of chroococcoid cyanobacteria and size-fractionated chlorophyll a biomass in the central and southern north sea waters during June/July 1989

The spatial and vertical distribution of phycoerythrin(PE)-containing chroococcoid cyanobacteria and the contribution of the <3 μm size fraction to overall phytoplankton chlorophyll a biomass were investigated in the central and southern North Sea during June and July 1989. PE-containing chroococcoid cyanobacteria cell numbers ranged between 6×10⁵ and 4.4×10⁷ cells·dm⁻³ and was typically between 0.5×10⁷ and 3×10⁷ cells·dm⁻³, lowest numbers being recorded near the British coast in central North Sea waters. The vertical distribution of these cyanobacteria showed no evidence to suggest a preferential accumulation deep in the euphotic zone. The <3 μm size fraction accounted for 6.6 to 57.5% of the total phytoplankton chlorophyll a biomass (mean 19.7%). In general, the relative significance of the <3 μm size fraction decreased with increasing total chlorophyll a biomass.     

Urban squatters and the poor in Fiji: Issues of land and investment in coastal areas

Pacific land issues are not only about Indigenous ownership in rural areas. Within urban areas in particular, land historically alienated into State control produced consequences only now being realised. In Fiji, all State land is claimed by communal landowners and such claims were said to be one reason for the 2006 coup. It has been suggested in recent times that urban informal settlements on the qoliqoli (coastal and foreshore land) are at risk and face increasing challenges from landowners. This paper examines a neglected area of urban State land in Fiji and comments on the future of the urban poor in Fiji if land tenure is unresolved.     

Introduction to special issue: Meeting the challenges of HIV/AIDS in Southeast and East Asia

Out of a total of 38 million people living with HIV/AIDS globally today, the Asia‐Pacific is home to about 7.4 million – a figure which constitutes a sharp rise to previous years. In absolute numbers, infections in Asia are projected to exceed African figures within a decade. This has largely to do with economic changes towards market‐based capitalism, widening socioeconomic disparities and increased levels of mobility (internal and cross‐border), as for instance in China and Indonesia. Overall, the epidemic in Asia has been described as more complex than in Africa involving a multiplicity of transmission modes. The case studies presented in the contributions to this special issue discuss the connections between issues of mobility, gender, (trans)nationalism and sexuality in understanding the HIV/AIDS challenge in the region. The various ways in meeting the challenges of HIV/AIDS in Southeast and East Asia are analysed, whereby non‐governmental and community‐based responses often emerge as more effective than state interventions.     

Orally transmitted texts of the minorities in East and Southeast Asia: Suggestions for research across borders

The rich body of orally transmitted texts kept alive by the people of the border country of Southwest China, both religious and secular provides a valuable source of information that has barely been tapped. The author believes that this time consuming task is well worth the effort. Even an exploratory review of selected parts of texts which focus on matters such as: how identity is constructed; what observations are made in the course of a journey to buy salt; general flora and fauna; and migration have more to tell us than is conveyed by the story. The possible rewards for those prepared to engage in textual analysis are likely to be considerable.     

我国小麦生产机械投入效率及影响因素分析——基于全国15个小麦主产省的实证

[目的]在国内农业劳动机会成本持续上升、国内外粮食价差不断扩大的背景下,我国小麦生产机械投入呈现持续增加趋势,研究农业机械投入效率对于优化财政支持效果具有重要意义。[方法]本文运用数据包络分析法对1998-2016年间我国15个主产省的小麦机械投入效率进行测算,并采用面板随机效应Tobit模型分析其影响因素。[结果]研究发现,我国小麦机械投入效率整体水平尚待进一步提升;小麦播种面积、排灌费用、实行最低收购价政策与机械投入效率负相关,表明我国小麦机械投入结构尚需优化,灌溉环节中的机械使用对投入效率的影响重大,国家政策对小麦生产主要环节和重要领域的支持至关重要。[结论]因此,应因地制宜推广小麦生产机械,注重农户灌溉投入的补贴和灌溉机械的优化,从政策层面鼓励农业机械技术创新研发,可提升农机行业的效率和竞争力。     

云南省沘江流域底泥中Pb污染分布特征及评价

为更好地了解沘江流域底泥中Pb的分布,以沘江流域底泥为研究对象,通过实地考察,应用统计分析等方法分析沘江流域底泥中Pb污染特征。结果表明：（1）沘江流域底泥Pb平均含量为1764.23 mg/kg;（2）底泥中Pb含量呈现上游>中游>下游趋势;（3）沘江流域底泥中Pb的单因子污染指数极高,上游、中游、下游平均单因子污染指数分别为6.04、2.51、2.03。综合分析流域底泥中Pb含量及单因子污染指数,发现沘江流域Pb污染状况严重,呈现上游>中游>下游趋势,极有可能影响沿岸农田土壤。