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1.
Sinclair  P.  Beckett  R.  Hart  B. T. 《Hydrobiologia》1989,176(1):239-251
Suspended particulate matter (SPM) was collected from two sites in the Yarra River, Australia under a range of flow conditions using a continuous flow centrifuge. The SPM from the upstream, largely rural, site at Warrandyte had higher concentrations of organic matter, phosphorus and manganese. SPM collected from the downstream, largely urban, site at Heidelberg had elevated concentrations of lead and zinc. The concentrations of iron, copper and chromium in the SPM changed little between the two sites.Over the study period, the flow-weighted mean concentration of SPM increased 5-fold between the two sites and the load increased 7-fold. The annual load of SPM transported past Heidelberg was estimated to be 170 000 tonne, with approximately 80% occurring during high flows (> 15 m3 s-1 ). Detailed study of the SPM concentrations during flood events suggests that the northern tributaries to the Yarra are the main contributors of SPM in the region between Warrandyte and Heidelberg.The mean annual load of total phosphorus transported by the Yarra River at Heidelberg was estimated to be 220 tonne, approximately 2.5 times greater than at Warrandyte. Approximately 60% of this load was associated with SPM. The majority (ca. 80%) of this SPM-bound phosphorus was extractable with 0.1 M NaOH, and is therefore potentially biologically available.There was little difference between the two sites in the flow-weighted mean concentrations of iron, copper and chromium in SPM. The manganese concentration was approximately halved between Warrandyte and Heidelberg, with most of the loss occurring in the exchangeable and reducible fractions. Lead and zinc concentrations in SPM increased 15 to 16-fold between the two sites, with most of this increase occurring in the exchangeable and reducible fractions. This is some cause for concern, since metals in both these fractions could become available to biota under conditions known to exist in the Yarra estuary.  相似文献   

2.
南海南部悬浮颗粒物脂肪酸组成   总被引:1,自引:1,他引:0  
中国水产科学研究院南海水产研究所"南锋号"科考船在2012年2月22日—3月20日调查期间,对南海南部海域0 m、75 m和150 m层水体悬浮颗粒物进行了脂肪酸(FA)组成的研究。FA含量在表层、75 m层和150 m层的变化范围分别为9.9—15.65μg/L,10.45-14.45μg/L和9.65—16.45μg/L。FA与叶绿素a的比值垂向变化非常大,在表层和150 m层都大于70,而在75 m层小于30(除A7)。悬浮颗粒物的FA组成以饱和脂肪酸和单不饱和脂肪酸为主,而多不饱和脂肪酸含量较低。饱和脂肪酸主要包括C16:0和C18:0,其次是C12:0,单不饱和脂肪酸主要包括C14:1n3、C16:1n7和C16:1n9,多不饱和脂肪酸主要为C18:2n6和C22:2n6。主成分分析表明,第一主成分主要与C16:0、C18:0、C20:0等正相关,可认为第一主成分主要表征浮游植物和碎屑,而第二主成分所表征的可能与浮游动物等有关的信息。悬浮颗粒物的脂肪酸标记物中,C16:1n7/C16:0和∑C16:1/∑FA之间呈显著正相关,同时C16:1n7/C16:0与∑C18/∑FA呈显著负相关,将C16:1n7/C16:0和C16:1/∑FA结合起来适宜于指示硅藻类的组成,∑C18/∑FA可用来指示甲藻类组成。  相似文献   

3.
梯级水电站开发对香溪河悬浮颗粒物粒径及浓度的影响   总被引:1,自引:0,他引:1  
韩霜  董正举  王欢  蔡庆华  邓红兵  吴钢 《生态学报》2008,28(8):3991-3997
通过对香溪河悬浮颗粒物粒度及浓度的实验分析,研究梯级水电站开发对河流悬浮颗粒物的影响,结果表明:(1)香溪河干流悬浮颗粒物粒径由上游到中游逐渐减小,并且在无水电站干扰时颗粒物粒径减小幅度较大;(2)从进水口至出水口河段,水电站悬浮颗粒物粒径总体变化不显著;(3)水电站从进水口河段至出水口河段,总悬浮颗粒物浓度(CTPM)在某些位置有所增加,有机颗粒物浓度(CPOM)无明显变化.悬浮颗粒物粒度及浓度的变化与水流流速及流量有着相当大关系.  相似文献   

4.
Aim To present a general, process‐based river model for suspended particulate matter (SPM). Location General approach based on processes; data from Europe and Israel. Methods The model has been tested and calibrated using an empirical river model for SPM and validated (blind‐tested) using data from seven European sites. This modelling gives mean monthly SPM concentrations in water for defined river sites. The model is based on processes in the entire upstream river stretch (and not for given river segments) and calculates the transport of SPM from land to water, primary production of SPM (within the upstream river stretch), resuspension, mineralization and retention of SPM in the upstream river stretch (but not bed load of friction materials, such as sand). The catchment area is differentiated into inflow (~ dry land) areas and outflow area (~ wetland areas dominated by relatively fast horizontal SPM‐fluxes). The model is simple to apply in practice as all driving variables may be accessed readily from maps. The driving variables are: latitude, altitude, continentality, catchment area and mean annual precipitation. Results Modelled values have been compared to independent empirical data from sites covering a relatively wide domain (catchment areas from 93 to 5250 km2, precipitation from 400 to 660 mm year?1, altitudes from ?210 to 150 m a.s.l., latitudes from 47 to 59° N and continentalities from 200 to 1000 km from the ocean). When blind‐tested, the model predicts annual SPM‐fluxes well. Conclusion When modelled values are compared to empirical data, the slope is almost perfect (1.03) and the r2‐value is 0.9996. This is good, given the fact that there are several simplifications in the model structure. It must, however, be stressed that there are only seven validation cases and that this model has not been tested for small catchments.  相似文献   

5.
水体中的悬浮颗粒物是物质在水环境中迁移转化的载体和蓄积库,是营养成分在水相、沉积物相和食物链中循环的重要载体,是河流生态系统物质循环和能量流动的重要组成部分[1—3],很多学者研究了悬浮物的组成、结构和粒度之间的关系,发现其粒度特征对于了解生态系统内部物质和能量循环转化过程具有重要意义[4,5]。三峡水库蓄水后,香溪河下游部分河段成为库区的一部分,相对于河流来说,流速的减小使更多的悬浮颗粒物发生沉降,营养物质富集,易暴发水华[6]。本研究在三峡水库香溪河库湾水华暴发过程中对不同水深的悬浮颗粒物在24h内的动态分布特征进…  相似文献   

6.
Sterols were analyzed in suspended particles collected in January 1991 in the Solo River system and in the Serayu River, Java, Indonesia. Free sterols were extracted from particles larger than 0.7 μm and analyzed, after derivatization into their trimethylsilyl esters, by GC and GC/MS. Concentrations of total sterols ranged from 438 to 7922 ng/1, or from 2.4 to 183.8 ng/mg of total suspended matter, which varied from 3.3 to 400 and 471 mg/l, respectively in the Serayu River and at the downstream station in the Solo River. POC concentrations also varied in a wide range, from 0.91 to 4.72 and 6.13% of TSM, respectively at the above stations, and were associated with sterol/POC values ranging from 0.15 to 1.75 μg/mg. Eleven structures of C27, C28 and C29 sterols and associated stanols were identified. 28Δ3,22 was only found at downstream stations in the Solo River and in the Serayu River. This unique distribution, different from that of other C27, C28 and C29 sterols, suggests a predominantly autochthonous origin for these compounds associated with an increased planktonic biosynthesis near the estuary. Concentrations of 28Δ5, 29Δ5,22 and 29Δ5 showed similar spatial distributions and increased downstream, reflecting the significant accumulation of organic matter originating from the vegetation of the various drainage basins. Values of the autochthonous versus terrigenous sterol index, defined as 27Δ5/29Δ5,22 + 29Δ5 were in the 1.4–1.9 range at upstream stations, whereas at downstream stations lower values were found, 0.4–0.6, which also corresponded to higher concentrations of TSM and lower POC values. Insofar as the stanol/stenol values can be used to estimate the bacterial activity of oxic waters, simultaneous variations of C27, and C29 stenol/stanol pairs suggest rather different bacterial degradation capacities of autochthonous versus allochthonous organic matter. The wide differencies between the values of the stenol/stanol pairs observed in one of the main tributaries and in downstream stations of the Solo River is evidence that allochthonous organic matter is much more resistant than autochthonous matter. The low index value observed in the Serayu River indicates the highly refractory nature of both autochthonous and allochthonous organic material.  相似文献   

7.
Summary The presence of heavy metals and Polynuclear Aromatic Hydrocarbons (PAH) has been evidenced in airborne particulate matters samples collected in the atmosphere of a non-industrialized middle size Italian town (150.000 inhabitants). The PAH concentrations, higher in winter than in other seasons, was inversely correlated with some meteorological variables such as temperature (p<0.01) and wind speed (p<0.05). The positive correlation found (p<0.01) between lead and total PAH seems to indicate traffic as the most important source of pollution.All samples were mutagenic in the Ames test and the highest mutagenicity levels were obtained in winter samples. The positive correlation found between Benzo(a)Pyrene {B(a)P} concentration and the number of revertants/m3 air, suggests that B(a)P could be an index of mutagenic potential of the matrix considered.The airborne particulate matter extracts obtained by organic solvents were able to inhibit the phagocytosis of mice alveolar macrophages, giving further proof of the possibility of interaction between air-particulate chemical compounds and important biological functions.  相似文献   

8.
1. Benthic communities inhabiting river–lake interfaces are confronted with temporal variation in the import of river‐borne material to the associated littoral zone. The primary objective of this study was to evaluate the exposure to river‐borne benthic particulate matter as a force shaping the meiofauna of the river–lake interface. 2. In a 2 × 2 factorial design, combinations of strongly and weakly river‐influenced communities (near or far from the river mouth) with and without river‐borne benthic particulate matter enrichment were studied in laboratory microcosms to assess the response of the heterotrophic meiobenthos to river‐borne matter. 3. Nematodes dominated both habitat types and were the only meiofaunal taxon that responded to the enrichment. 4. A strong interactive effect between experimental enrichment and location of site was observed. Whereas nematodes from the littoral habitat close to the river mouth responded to the enrichment only marginally, nematodes from the remote site were strongly affected in the presence of river‐borne particulate matter. 5. In the non‐enriched samples of the remote site, the number of nematodes increased greatly over time. Among nematode feeding types, deposit feeders dominated over chewers at the beginning of the experiment but both types were equally abundant at the end. In the presence of river‐borne matter the increase of chewers ceased and a shift in feeding type composition did not occur. 6. It was shown that for river–lake interface meiofaunal assemblages in relative proximity, the same taxon might respond differently if exposed to an external pressure, e.g. river‐borne components. These components may have a stronger influence on taxa with longer life cycles.  相似文献   

9.
M. Nagai  M. Sugiyama  T. Hori 《Limnology》2001,2(3):147-155
During the period from July 1992 to March 1995, suspended particulate matter in Lake Biwa was collected at 1-month intervals, and the contents of Al, Si, and P were determined. Based on the analytical data, the particulate matter was fractionated by calculation into three types of particles of different origins: particles of terrigenous origin, particles of diatom origin, and particles due to microorganisms except for diatoms. The relative abundance of the respective particles was featured in water depth-time (month) diagrams, with contours in terms of weight per liter of lake water. As a result, the characteristic distributions of the particles were revealed, and their inherent roles in natural purification were distinguished from each other. Of the three types of particles, the particles of diatom origin were anticipated to be the principal scavengers not only of nutritious elements of silicon and phosphorus, but also of various metal ions dissolved in the lake. Received: October 5, 2000 / Accepted: June 6, 2001  相似文献   

10.
颗粒有机质的来源、测定及其影响因素   总被引:4,自引:1,他引:4  
土壤活性有机质及其组分作为土壤质量的重要指标在土壤化学、物理和生物性质方面起着重要作用。颗粒有机质能够有效地反映有机质的特性,与微生物生长、营养供给及C、N的生物学调节密切相关。作为活性有机质的一个量度指标,颗粒有机质越来越受到人们的重视。本文综述了土壤颗粒有机质的来源及其在土壤有机质转化过程中的作用,对其测定方法作了系统的描述,阐明了土壤理化性质、农业措施(施肥与耕作)及土地利用类型对土壤颗粒有机质在土壤形成及维持其稳定性方面的影响。  相似文献   

11.
The Godavari River, the third largest river of India,has been sampled for Particulate Inorganic and OrganicCarbon (PIC, POC), Particulate Nitrogen (PN), andParticulate Amino Acids (PAA, including 2 hexosamines(HA)). During the dry season Particulate OrganicMatter (POM) in the upper reaches is relatively freshand autochthonous, in the lower reaches it is degradedand inorganic suspended matter content is higher here.In the wet season (wet monsoon) heavy rains cause abasin-wide flushing of humus from entire catchmentarea consequently POM in the river is mainly degradedand allochthonous. Annual transport of the GodavariRiver amounts to 2.81 × 10 6 ton POC, 0.29 × 10 6ton PN and 0.10 × 10 6 tonParticulate Amino Acid Nitrogen. These amounts rank theGodavari River to one of the most important organic carbontransporting rivers in the world.  相似文献   

12.
Sedimentation field-flow fractionation (SdFFF) offers great potential for the separation of submicrometer and micrometer-sized species. The availability of commercial instrumentation and the versatility of this method originated its success. At this stage of development, SdFFF techniques are mature enough for use in analytical research, development and even routine work. However, prior to their use, these techniques like any other methodologies, have to be validated. As the application of SdFFF techniques to cell separation is being constantly developed, we have investigated separation performance according to validation rules classically defined for separation methods (chromatography) in the case of cellular materials.  相似文献   

13.
森林植被与大气颗粒物的关系   总被引:4,自引:0,他引:4       下载免费PDF全文
近年来,大气颗粒物成为我国城市大气的主要污染物,其中细颗粒物(PM2.5)粒径小、沉降困难,对环境的危害已成为亟待解决的问题。森林植被可显著消减空气颗粒物,有效改善空气环境质量。本文概述了植被对颗粒物的移除过程和方法,探讨了大气颗粒物与森林植被的相互关系。从单叶、单木及群落3个尺度,结合气象因素讨论了植被对移除大气颗粒物的影响,分析了颗粒物的后续再悬浮过程及对植被的危害。最后,从植被吸附颗粒物的能力测定和评价、本土高吸附PM2.5能力植被的筛选及综合研究不同植被配置结构的吸附效应等方面提出了植被吸附颗粒污染物,尤其是细颗粒物的研究重点与趋势。  相似文献   

14.
Hollow fiber flow field-flow fractionation (HF FlFFF) has been demonstrated as a tool for pre-fractionating proteomes by differences in molecular mass (Mr), where the resulting protein fractions are subsequently digested and analyzed by shotgun proteomics using two-dimensional liquid chromatography-electrospray ionization-tandem mass spectrometry (2D-LC-ESI-MS/MS). HF FlFFF is a separation device capable of fractionating proteins or cells by hydrodynamic radius, and protein fraction can be readily collected as intact conditions in aqueous buffer solutions. In this study, HF FlFFF was applied to fractionate the proteome of Corynebacterium glutamicum, a well known soil bacterium that has been widely used in bioindustry due to its remarkable ability to secrete high amounts of glutamic acid. The collected HF FlFFF fractions of different MW intervals were enzymatically digested for protein identification by 2D-LC-ESI-MS/MS. Experiments showed improvements in protein identification when HF FlFFF pre-fractionation was applied, due to decreases in the ionization suppression effect and the MS exclusion effect by spectral congestion. Pre-fractionation of C. glutamicum proteome allowed us to find 90 additional proteins by 2D-LC-ESI-MS/MS that were not found by a direct shotgun analysis without pre-fractionation. A total of 415 proteins were found overall with 203 proteins commonly found from experiments with and without pre-fractionation.  相似文献   

15.
城市森林调控空气颗粒物功能研究进展   总被引:16,自引:1,他引:16  
王晓磊  王成 《生态学报》2014,34(8):1910-1921
受城市扩张、工业发展、汽车保有量增加的影响,空气颗粒物目前已成为诸多城市空气的首要污染物。而城市森林作为城市生态建设中最大的唯一具有自净功能的生态系统,不仅为城市高污染环境下的居民提供了相对洁净的休闲游憩空间,还对净化空气颗粒物起重要作用。从城市森林调控空气颗粒物的机理、分析方法、植物个体、群落及不同类型城市森林调控空气颗粒物的功能差异及其时空变化规律等方面进行阐述。结果表明:目前有关物理降尘的研究较多,涉及化学除尘的研究尚缺;应用重量法测定植物滞尘量的研究较多,质量浓度法测定城市森林净化空气颗粒物功能的研究较少。在未来一段时间,森林植被化学除尘的过程与机理,城市森林调控空气颗粒物的多方面、系统性研究及相关研究成果的转化与实际应用将会是重要的研究方向。  相似文献   

16.
Transport of coarse particulate organic matter in an Idaho river,USA   总被引:1,自引:1,他引:0  
Ted R. Angradi 《Hydrobiologia》1991,211(3):171-183
I investigated organic matter transport in the Henry's Fork of the Snake River, Idaho, USA, from August 1987 to November 1988. Mean discharge during the study was 15 m3 s–1. Screens were used to sample very coarse (> 6 mm) transported aquatic macrophyte material (VCTMM). Drift nets were used to sample coarse (1–6 mm) and fine (0.25–1 mm) transported particulate organic matter (CTOM and FTOM). Mean monthly concentration of VCTMM was 0.064 mg AFDWl–1 and was significantly higher than CTOM (0.024 mg AFDW l–1) and FTOM (0.036 mg AFDW l–1). VCTMM concentration was highest in December (0.163 mg AFDW l–1) and lowest in May (0.018 mg AFDW l–1). The sample position along a transect across the channel had a significant effect on the amount of transported organic matter collected in many months. The concentration of debris from individual species tracked the standing stock of that species during the growing season. In Fall, a dramatic increase in VCTMM corresponded to a decrease in macrophyte standing stock. FTOM and CTOM concentrations were highest in January (CTOM: 0.048; FTOM: 0.111 mg AFDW l–1), lowest in November 1988 (<0.006 mg AFDW l–1), were not correlated with discharge, and were inversely correlated with the standing stocks of macrophytes upstream, probably because macrophyte beds influenced the retentiveness of the channel. Standing stock of aquatic macrophytes was highest in September–October (5.2 kg wet weight m –2) and lowest in February (1.7 kg wet weight m–2). Annual movement of particulate organic matter past the sampling point was about 45 000 kg AFDW, of which 21 000 kg was VCTMM, 8 000 kg was CPOM, and 16 000 kg was FPOM.  相似文献   

17.
van Eck  G. T. M. 《Hydrobiologia》1982,91(1):665-681
The composition and the different forms of P, in an annual average sample of particulate matter, have been determined to define the nature of the very high concentration of particulate P in the inflowing water of the Hollands Diep/ Haringvliet (The Netherlands), and to assess its potential to stimulate the growth of aquatic organisms. Three phosphorus fractionation schemes and five other extraction procedures have been applied. Seventy per cent of the total phosphorus content is operationally defined as Fe- and Al-bound P but, probably, only a discreet Fe-phosphate is present, with an atomic ratio Fe/P = 1.5. About 50% of total P is present as a colloidal form (<0.45 μm). The results indicate that Murphy & Riley's procedure for orthophosphate determination causes some hydrolysis of labile organic phosphorus compounds. A fractionation scheme, to determine the different forms of P in particulate matter, is proposed. The concentration of potentially algal-available particulate P, which varies between 25 and 50 μg P 1, has probably no effect on water quality because the concentration of dissolved orthophosphate (250 μg P 1−1) is much higher. The huge amounts of Fe-bound P stored in the sediments, however, may retard the improvement of water quality in the future when reduction of the phosphorus loading has been accomplished.  相似文献   

18.
The role of alveolar macrophages (AMs) in chronic obstructive pulmonary disease is unclear. We characterized the function of AMs in rats chronically exposed to biomass fuel smoke (BMF) and studied the signal pathways that regulate AMs polarization. One hundred and eighty male Sprague‐Dawley rats were divided into BMF group and clean air control (CON) group. After BMF smoke exposure for 4 days, 1 month and 6 months, the cytokine secretion and function of AMs were determined by flow cytometry, quantitative polymerase chain reaction, Western blotting and immunofluorescence. Bone marrow‐derived macrophages were cultured and exposed to particulate matter (PM) from the smoke. Exposure initially promoted pro‐inflammatory factors, but pro‐inflammatory macrophages shared features of anti‐inflammatory macrophages. Consistent with IL‐4 upregulated in bronchoalveolar lavage fluid, p‐Stat6 and peroxisome proliferator‐activated receptor γ (PPARγ) in AMs elevated at 4 days of exposure. After 6 months of exposure, CD206, TGF‐β1 and p‐Smad3 were significantly higher than the control groups. PPARγ reversed the M1 phenotype induced by PM in vitro and drove the macrophages into the M2 phenotype. Altogether, the study demonstrates the dynamic phenotype and functional changes in AMs during exposure to BMF smoke.  相似文献   

19.
The effect was determined of organo-mineral detritus (OMD), one of the components of suspended mineral matter in aquatic ecosystems, on the production characteristics of bacterioplankton (bacterial production P b and destruction of organic matter R b, as well as bacterial growth efficiency BGE). The relation was determined between these parameters and the ratio of the content of suspended mineral matter M to the total organic carbon content (M/TOC). More active utilization of organic matter by bacterioplankton in the presence of OMD resulted in its positive effect on specific production characteristics of the phytoplankton.  相似文献   

20.
Biotic and abiotic particles shape the microspatial architecture that defines the microbial aquatic habitat, being particles highly variable in size and quality along oceanic horizontal and vertical gradients. We analysed the prokaryotic (bacterial and archaeal) diversity and community composition present in six distinct particle size classes ranging from the pico‐ to the microscale (0.2 to 200 μm). Further, we studied their variations along oceanographic horizontal (from the coast to open oceanic waters) and vertical (from the ocean surface into the meso‐ and bathypelagic ocean) gradients. In general, prokaryotic community composition was more variable with depth than in the transition from the coast to the open ocean. Comparing the six size‐fractions, distinct prokaryotic communities were detected in each size‐fraction, and whereas bacteria were more diverse in the larger size‐fractions, archaea were more diverse in the smaller size‐fractions. Comparison of prokaryotic community composition among particle size‐fractions showed that most, but not all, taxonomic groups have a preference for a certain size‐fraction sustained with depth. Species sorting, or the presence of diverse ecotypes with distinct size‐fraction preferences, may explain why this trend is not conserved in all taxa.  相似文献   

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