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1.
To investigate the spatio-temporal and compositional variation of selected water quality parameters and understand the purifying effects of wetland in Fujin National Wetland Park(FNWP), China, the trophic level index(TLI), paired samples t-test and correlation analysis were used for the statistical analysis of a set of 10 water quality parameters. The analyses were based on water samples collected from 22 stations in FNWP between 2014 and 2016. Results initially reveal that total nitrogen(TN) concentrations are above class V levels(2 mg/L), total phosphorus(TP) concentrations are below class Ⅲ levels(0.2 mg/L), and that all other parameters fall within standard ranges. Highest values for TN, pH, and Chlorophyll-a were recorded in 2016, while the levels of chemical oxygen demand(COD_(Mn)) and biochemical oxygen demand(BOD5) were lowest during this year. Similarly, TN values were highest between 2014 and 2016 while dissolved oxygen(DO) concentrations were lowest in the summer and TP concentrations were highest in the autumn. Significant variations were also found in Secchi depth(SD), TN, CODMn(P 0.01), TP, and DO levels(P 0.05) between the inlet and outlet of the park. High-to-low levels of TN, TP, and TDS were found in cattails, reeds, and open water(the opposite trend was seen in SD levels). Tested wetland water had a light eutrophication status in most cases and TN and TP removal rates were between 7.54%–84.36% and 37.50%–70.83%, respectively. Data also show no significant annual changes in water quality within this wetland, although obvious affects from surrounding agricultural drainage were nevertheless recorded. Results reveal a high major nutrient removal efficiency(N and P). The upper limits of these phenomena should be addressed in future research alongside a more efficient and scientific agricultural layout for the regions in and around the FNWP.  相似文献   

2.
The incidence of the airborne fungal spores was determined in the air of subalpine zone of the Karkonosze Mountains and of the Izerskie Mountains in the borderland between Poland and the Czech Republic. The experiment was conducted in 2011 and 2012 at three to four week intervals from May to October. Air samples were taken from three locations in the Karkonosze Mts. and one from the Izerskie Mts. To examine the air, the Air Ideal 3P sampler and acidified PDA medium were used. The results show that Cladosporium cladosporioides was the most abundant spore type in all the sampling locations (up to 30%), followed by Alternaria alternata (16%-20%), Fusarium (up to 10%) and Sclerotinia sclerotiorium (up to 6%). The lower spore counts were recorded in May samples, compared to the other months. In this case the snow cover, that was still present in the area at the beginning of May, may be the reason for the lower, compared to June, July and August samplings, CFU (Colony Forming Unit) counts in that month.. The influx of air masses from SE, S and SW sectors in the area under study may affect dissemination of the plant-pathogenic fungi from the Czech Republic and from the South of Europe in general.  相似文献   

3.
Exploring transport patterns of soil contaminants is essential for solving the problem of heavy metal contamination in mine soils. In this study, contamination of Pb, Zn, and Cd in the mountain soils of the lead–zinc ore mines in Ganxi Township, Hengdong County, Hunan Province, China was investigated, and their transport patterns were further explored using a soil-column model and numerical simulation techniques. In total, 111 mine soil samples were collected and placed into six experimental soil columns. By controlling the water flow, a control soil column group(CK), two mixed soil columns X_1 with daily water flows of 1 and 5 L, and three mixed soil columns X_3 with daily water flows of 2, 3, and 4 L were evaluated. The results showed that the residual fraction of Pb accounted for 71.93 % of the content on average, whereas the exchangeable fractions of Zn, Cd, and Fe-Mn oxide-bound fractions of Zn and Cd accounted for 28.60%, 31.07%, and 43.2% and 53.54% of the content, respectively. Pb, Zn, and Cd in the soils of the CK, X_1, and X_3 groups mainly were accumulated at a depth from approximately 0 to 20 cm, and the content at this depth accounted for 60.09% of that at a 0~40 cm depth. The soil at a depth range of 0~10 cm was most seriously contaminated, and the proportion of content was 32.39% of that at a 0~40 cm depth. Numerical simulation showed that on the 5 th day, the pollutant transport range was 0~24 cm, and on the 9 th day, the pollutant transport range exceeded 40 cm. On the 15 th day, the transport capacity of pollutants at depths of 0~40 cm was close to the stable state, but the soil at a depth of 0~10 cm was still heavily polluted. These results reflect the transport pattern of heavy metal pollutants in the soil of lead–zinc ore mines and may provide a reliable scientific support for the prevention of heavy metal contamination in mine environments.  相似文献   

4.
Harmful cyanobacterial blooms cause many ecological disasters worldwide. During the development of cyanobacterial blooms, the diversity and domination of cyanobacterial taxa are of a particular concern. In this study, the microbial community structure within a water system, such as in Yuqiao Reservoir and Haihe River in Tianjin City, China, was compared by using next-generation sequencing. A total of 5 001 operational taxonomic units were obtained and clustered from filtered 16 S rDNA V3–V4 region sequences. The cyanobacterial and microbial structures greatly differed in these two water areas. Microcystis was dominant in Yuqiao, whereas Synechococcus was dominant in Haihe. Proteobacteria species were dominant among all detected samples. The relative abundances of Bacteroidetes and Planctomycetes were higher in Yuqiao Reservoir than in Haihe River, whereas Firmicutes and Verrucomicrobia were relatively abundant in Haihe River. Further analyses indicated that the domination of both cyanobacteria was strongly related to several environmental factors, such as total nitrogen, total phosphorus, and dissolved oxygen, reflecting the role of trophic states in shaping the dominance of cyanobacterial taxa. The present study provided the example for Microcystis and Synechococcus dominance along a cyanobacterial bloom in north China. Applying highthroughput sequencing could offer a wide field of vision in analyzing microbial community structures.  相似文献   

5.
The composition and distribution of benthic, periphytic and planktonic rotifers in different habitatsin Krottensee were investigated. Sixty-five rotifer taxa were identified, their relative abundance estimated. Classification of the data set by cluster analysis allowed the recognition of distinct habitat groupe con-fined to acid bog ponds, macrophytes, sediments, and open water. Five groups of rotifer taxa were identifiedon the basis of their habitat preferences and the occurrence of the taxa. Highest diversities were found onmacrophytes and in acid bog ponds.  相似文献   

6.
The authors took the ETM + multi-spectra data as the data information and correlation coefficient for each band and carried out their information volume statistics. According to certain criteria, the authors also determined the optimum band-combined image. The image clarity is improved by various enhancements and fusions method. Based on remote sensing geological interpretation in detail, the relationship between remote sens- ing geological characters and gold mine were analyzed systemically. Using all kinds of remote sensing structure information, combining other research data, the authors determined mainly ore-controlling ore structure. Several prospective areas of gold ores were determined and furthermore significant finding mine target areas was confirmed.  相似文献   

7.
8.
The Nuanquangou loess section in the Longxi Basin has been examined in terms of stratigraphic investigation,. including 14C dating, paleomagnetic polarity, spore-pollen diagram, and mineral and chemical analyses. The results indicate that the section is one of the ancient loess sections with a continuous sedimentation and composed of homogeneous materials with abundant carbonate. The Brunhes / Matuyama boundary and the Jaramillo event were recorded in the section. Stratigraphically,this section can be divided into the Holocene and the Pleistocene loess. The latter includes Malan, Lishi and Wucheng loess in descending order. They were developed at about 1.2 Ma ago, whereas the Nuanquangou loess section possesses some local characteristics different from those observed in other areas.  相似文献   

9.
The Yarlung Zangbo River Basin(YZRB) is situated in the southern part of the Tibetan Plateau and remains in a mostly natural state. To understand the chemical characteristics of spring water and its controlling factors in the YZRB, 68 sets of spring water samples were analyzed using hydrochemical and isotopic techniques. The spring water was found to be slightly alkaline with total dissolved solids(TDS) below 1000 mg L-1. Major ions were Mg2+, Ca2+, SO42-, and HCO3-. The spring water types in this basin were determined to be HCO3-Ca·Mg and SO4·Cl-Ca·Mg. Ion exchange and dissolution of carbonate, gypsum, and silicate were identified as the prevalent hydrogeochemical processes contributing and defining spring water chemistry in this basin. Saturation indices(SI) of most major minerals studied in this region were below zero, indicating that these minerals remain under-saturated in the spring water in this area. Overall, the rank of different processes in terms of their contribution to the chemical composition of spring water in the YZRB was carbonate weathering evaporate dissolution silicate weathering precipitation input. The content of 18 O in spring water ranged from-22.22‰ to-14.08‰ with a mean of-18.15‰. Samples collected below and close to the local and global meteoric water lines indicated that spring water in this area is derived from meteoric water with chemistry affected by evaporation.  相似文献   

10.
According to the Geological settings and the distributed laws of ore bodies and previous research results, combining with latest theories and new methods of geological prospecting, the authors proposed prospecting thoughts for substituted resources in Laozuoshan gold deposit. After ore prospecting in two years, nine new blind ore bodies were found, among which four ore bodies contain 4218.1 kg inferred intrinsic economic resources (333), and mitigate the crisis situation of mine reserves. At the same time, lots of significant geophysical and geochemical anomalies were found in the peripheral, which provide a basis for further prospecting.  相似文献   

11.
Changes in tissue structure, rheological property and water content of dry abalone meat in the process of water restora- tion were studied. The weight and volume of dry abalone meat increased with water restoration. When observed under a light micro- scope, structural change in myofibrils was obvious and a distinct network was found. When water restoration time increased from 24 h to 72 h, the instantaneous modulus E0 and viscosity η1 increased, whereas the rupture strength and relaxation time (τ1) were re- duced. There were no significant changes of rheological parameters (E0, η1, τ1, rupture strength) from 72 h to 96 h of water restoration. Therefore, the dry abalone meat was swollen enough at the time of 72 h. The rheological parameters were obviously influenced by the structural changes.  相似文献   

12.
During the First Chinese Antarctic Expedition zooplankton samples were collected at each of the oceanography stations in the waters around South Sheltland Islands (S. S. Is.) and in the northern part of the Bellinshausen Sea from 20 January to 12 February, 1985 by vertical tows of an 80 cm diameter conical net from 200 m to surface. Two deep tows with a closing net. were performed in slope water north of S.S. Is, and in the basin of Bransfield Strait. Eggs and larvae of Euphatisia superba Dana in zooplankton samples were identified and counted.There were four records of eggs from 27 stations. Most catches were of small number and restricted to within the nearshore area south of S.S Is.The largest number (1500/1000 cubic meters )was found in the outer side of Smith Island.No Nauplius was found . The earliest stage we found 相似文献   

13.
The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater samples and five sediment samples sourced in May 2011. A total of 22 phyla, 34 classes, 74 orders, 146 families, and 333 genera were identified in this study. Some of them were detected for the first time from the East China Sea. The estimated richness and diversity indices were both higher in the sediment samples compared with in the seawater samples. All the samples were divided by their diversity indices into four regions. Similarity analysis showed that the seawater samples could be classified into six groups. The groups differed from each other and had unique community structure characteristics. It was found that different water masses in the sampling areas may have had some influence on the bacterial community structure. A canonical correspondence analysis revealed that seawater samples in different areas and at different depths were affected by different environmental parameters. This study will lay the foundation for future research on microbiology in the East China Sea.  相似文献   

14.
The Berezovsk coal mine in western Siberia has yielded the most diverse Middle Jurassic limnic and terrestrial vertebrate assemblage of Asia.The vertebrate remains were recovered by screen washing from flood-plain deposits on top of a thick coal seam of the Bathonian Itat Formation.A total of 29 vertebrate taxa has been recorded so far,including hybodontiform sharks,acipenseriforms,palaeonisciforms,amiiforms,dipnoans,anu-rans,caudates,turtles,squamates,choristoderans,crocodyliforms,pterosaurs,dinosaurs,tritylodontids,and a diverse mammaliaform and mammalian assemblage (eleutherodontids,docodontans,?amphilestids,dryo-lestids,and zatherians).The caudates are among the oldest in the fossil record and the anurans represent the oldest Asian record of this group.Among the mammals,Anthracolestes is the oldest and most basal known mem-ber of Dryolestidae and so far the only record from Asia.The vertebrate assemblage from the Berezovsk coal mine is very similar to that from the British Forest Marble Formation (Bathonian)and suggests a limited provin-cialism in the Middle Jurassic Laurasian landmass.  相似文献   

15.
Air entrapment is an important consideration in environments with shallow water tables and sandy soil, like the condition of highly conductive sandy soils and flat topography in Florida, USA. It causes water table rises in soils, which are significantly faster and higher than those in soils without air entrapment. Two numerical models, Integrated Hydrologic Model (IHM) and HYDRUS-1D (a single-phase, one-dimensional Richards′ equation model) were tested at an area of west central Florida to help further understanding the shallow water table behavior during a long term air entrapment. This investigation employed field data with two modeling approaches to quantify the variation of air pressurization values. It was found that the air pressurization effect was responsible at time up to 40 cm of water table rise being recorded by the observation well for these two models. The values of air pressurization calculated from IHM and HYDRUS-1D match the previously published values. Results also indicated that the two numerical models did not consider air entrapment effect (as the predictive parameters remain uncertain) and thus results of depth to water table from these models did not compare to the observations for these selected periods. Incorporating air entrapment in prediction models is critical to reproduce shallow water table observations.  相似文献   

16.
The present paper reports Zn,Cu,Pb,Cd,Ni,Fe,Mn and Co contents in the tissues of oyster,solen,red-tail prawn,sea eel and kelp,taken from Meizhou Bay(and analysed by flame atomicabsorption spectrophotometry after wet digestion)in June 1992,and also the concentration factors esti-mated from the mean metal concentrations in the organisms and water there.Heavy metal concentrationsin every species of the organisms followed the pattern:Fe,Mn,Cu,Zn>Pb,Cd,Ni,Co and in variousorganisms showed considerable variation.In general,levels of most of these metals were in the order:softtissues of the bivalves>the kelp>muscles of the red-tail prawn,the sea eel.The greatest concentrationof most metals was found in the gill or viscera of the sea eel,whereas the muscle tissues,in general,con-tained only low concentrations of them.The Cu,Zn concentration factors of the oyster were higher by1—2 orders of magnitude than that of the other organisms.The observed heavy metal levels were closeto those reported from various waters  相似文献   

17.
The chemical composition of several thermal springs around Changbaishan area has been investigated. Cenozoic basaltic rocks are widely distributed in Northeast China and geothermal characteristics have been described. About one hundred hot springs exist around Changhaishan Volcano at the border between China and D.P.R.Korea with high temperature about 82~C. The pH values of the spring water range from 6.9 to 7.1 and the total flow rate is about 4.8 L/sec. The chemical composition of the thermal springs is sodium carbonate; the high-mineral contents of thermal water are believed to have medicinal properties. Bathhouses are already built along the hot springs to take the advantage of the supposed healing properties. The high quality of those hot springs is believed to be utilitized for mineral water. The chemical equilibrium temperatures were estimated at about 160℃ based on the Na-K-Ca geochemical thermometer.  相似文献   

18.
The Java Island, Indonesia with abundant amount of pyroclastic deposits is located in the very active and dynamic Pacific Ring of Fires. Studying the geochemical weathering indices of these pyroclastic deposits is important to get a clear picture about weathering profiles on deposits resulting from the eruption of Mt. Merapi. Immediately after the first phase of the eruption (March to June 2006), moist and leached pyroclastic deposits were collected. These pyroclastic deposits were found to be composed of volcanic glass, plagioclase feldspar in various propoitions, orthopyroxene, clinopyroxene, olivine, amphibole and titanomagnetite. The total elemental composition of the bulk samples (including trace elements and heavy metals) was determined by wet chemical methods and X-ray fluorescence (XRF) analyses. Weathering of the pyroelastic deposits was studied using various weathering indices. The Ruxton ratio, weathering index of Parker, Vought resudual index and chemical index of weathering of moist pyroclastic deposits were lower than those of the leached samples, but the alteration indices (chemical and plagioclase) were slightly higher in the moist compared to the leached pyroelastic deposits.  相似文献   

19.
Two types of pisha-sandstones of purple sandstones and gray sandstones, widely distributing in the wind-water erosion crisscross region of China, were selected and used in laboratory experiments for a better understanding of the drying-wetting-freezing weathering process resulting from the apportionment of water or salt solution to rock samples. Weathering experiments were carried out under the conditions of environment control (including temperature, moisture and salt solution). All rock samples were frequently subjected to 140 drying-wetting-freezing cycles. The influences of weathering process were evaluated. It was found that the different treatments of moisture and salt solution applications could affect the nature of the weathering products resulting from drying-wetting-freezing. It was also observed that salt solution could effectively alleviate the weathering of pisha-sandstones. Although not all the observations could be explained, it was apparent that simulated environmental factors had both direct and indirect effects on the weathering of rocks.  相似文献   

20.
Ethnobotanical studies in the Balkans are crucial for fostering sustainable rural development in the region and also for investigating the dynamics of change of Traditional Ecological Knowledge(TEK),which has broad-sweeping implications for future biodiversity conservation efforts.A survey of local botanical and medical knowledge and practices was conducted in four mountainous villages of the Peshkopia region in northeast Albania,near the Macedonian border.Snowball sampling techniques were employed to recruit 32 informants for participation in semi-structured interviews regarding the use of the local flora for food,medicinal,veterinary and ritual purposes.The uses of 84 botanical taxa were recorded as well as a number of other folk remedies for the treatment of both humans and livestock.Comparison of the collected data with another ethnobotanical field study recently conducted among Albanians living on the Macedonian side of Mount Korab shows a remarkable divergence in medicinal plant uses,thus confirming the crucial role played by the history of the last century in transforming TEK.Most noteworthy,as a legacy of the Communist period,a relevant number of wild medicinal taxa are still gathered only for trade rather than personal/familial use.This may lead to unsustainable exploitation of certain taxa(i.e.Orchis and Gentiana spp.) and presents some important conservation challenges.Appropriate development and environmental educational frameworks should aim to reconnect local people to the perception of limitation and renewability of botanical resources.  相似文献   

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