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Water potential of the Goc mountain [Serbia, Yugoslavia] in the function of sustainable management of the forest ecosystems
1998
Ristic, R. (Sumarski fakultet, Beograd (Yugoslavia)) | Macan, G. | Malosevic, D. | Nikic, Z. | Macan, I.
Mountain Goc is one of the regions with the highest water potential in Central Serbia (Yugoslavia), with specific annual runoff of 12-17 l/s per square km. Upper part of the catchment area of the Gvozdacka River has 111 springs, on the surface of 13.3 square km. 33 springs has volume yield from 0.5 to 2.5 l/s, with physical and chemical parameters of high water quality. These springs never dry up, even during years with low amount of precipitation. The upper part of the catchment area of the Gvozdacka River is under association Abieti-Fagetum, which is one of the worthiest in Serbia (Yugoslavia). Besides annual amount of precipitation, characteristics of soil, hydro-geological attributes of rock masses, influence of vegetation on processes of interception and evapotranspiration, which are very important factors for preservation of springs and their volume yield, also the system of forest ecosystems management. Not adequate measures in exploitation of forests lead to decreasing of volume yield of springs, and often to their disappearing.
Show more [+] Less [-]Spring waters of Goc serpentine [Serbia, Yugoslavia]
1999
Ristic, R. (Univerzitet u Beogradu, Beograd (Yugoslavia). Sumarski fakultet) | Macan, G. | Nikic, Z. | Malosevic, D.
During the summer 1998 the second phase of Cadastre of Water Objects on the Teaching Base Goc, on the Goc mountain, in central Serbia (Yugoslavia) was done. Investigation was carried out on the territory of 20 square km, with serpentine as parent rock. Serpentine is decomposed in the surface layer, with sceletal soil up to 50 cm deep, insignificant retention attributes. Dominate surfaces under bare lands, meadows, pastures and degraded forest stands. 35 springs were registered, small volume yield (up to 0.29 l*/s), with pH=7.5 to pH8.5, electrical conductivity from 80 up to 800 microS*/cm, temperature 7.0-17.0 deg C. Springs are permanent, but on the higher parts could dry up. Water level in the serpentine has small hydraulic gradient, with slope to the zones of out flow, in other words, to the local erosion base. Hydrogeological characteristics of serpentine were analyzed detailed.
Show more [+] Less [-]Towards understanding of microflora and microfauna of water bodies in the area of Mali Krs [Serbia, Yugoslavia]
1999
Ratajac, R. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Rajkovic, D. | Stojkovic, S. | Bobic, M.
In April 1997 and 1998 investigations of algae, Rotatoria, Cladocera, Copepoda and Hydracarina were conducted. The investigated localities were 8 small water bodies at around 800 m a.s.l., at Mali Krs, in the surrounding of Bor, Serbia (Yugoslavia). The aim was to examine composition of these groups and to give the evaluation of the quality of water. Among algae, according to the number of taxons, the dominant group was Bacillariophyta (45), then Chlorophyta (17), Cyanophyta (3), Euglenophyta (4), Xanthophyta (1) and Pyrrophyta (1). Rotatoria were present with the highest number of taxons among microfauna. In these investigations 48 taxons were present. The highest number of taxons was among Cephalodella, Corurella, and Trichocerca. Among Cladocera 4 taxons were present, and among Copepoda 9 taxons, and all the present species were found in our previous investigations. Hydracarina were present with 3 species, also with high diversity. Around two thirds of all taxons are oligosaprobionts, which indicates to the good quality of the water.
Show more [+] Less [-]The physical and chemical characteristics of spring water by the village of Berkovac in the foot of Maljen [mountain, Serbia, Yugoslavia]
1999
Prodanovic, D. (Institut za primenu nauke u poljoprivredi, Beograd (Yugoslavia)) | Aleksic, D. | Biocanin, N.
It has been done the analysis of the physical and chemical characteristics of the water from two households in the village Berkovac in the foot of the mountain Maljen, Serbia (Yugoslavia). These households are supplying from two different springs. The water from the spring "Dobracinovica izvor" is contaminated and it is not for use, but the quality of the water from the hill Kulica is satisfactory. Both of them belong to the group of cold mineral waters.
Show more [+] Less [-]Short- and medium-chain chlorinated paraffins in honey from China: Distribution, source analysis, and risk assessment
2022
Dong, Shujun | Qi, Suzhen | Zhang, Su | Wang, Yaxin | Zhao, Yin | Zou, Yun | Luo, Yiming | Wang, Peilong | Wu, Liming
Chlorinated paraffins (CPs) are industrial chemicals produced in large quantities. Short-chain CPs (SCCPs) were classified as persistent organic pollutants under the Stockholm Convention in 2017. Medium-chain CPs (MCCPs) became candidate persistent organic pollutants in 2021. CPs are now ubiquitously found in the environment. Honey bees can be exposed to CPs during foraging, and this exposure subsequently results in the contamination of honey and other bee products along with colony food production and storage. Here, SCCP and MCCP concentrations in honey collected from Chinese apiaries in 2015 and 2021 were determined. Total CP concentrations in honey from 2021 to 2015 were comparable, but the ratio of MCCPs/SCCPs was higher in 2021 than in 2015. SCCP and MCCP congener group profiles in all honey samples were similar and dominated by C₁₀–₁₁Cl₆–₇ and C₁₄Cl₆–₇, respectively. MCCP concentrations were also higher than SCCP concentrations in bees, pollen, and wax but not in bee bread, which were all collected in 2021. The order of average CP concentrations was determined as wax > bee > pollen > bee bread > honey. Poor relationships were found between SCCP concentrations in honey and other samples, but a relationship between MCCP concentrations in honey and other samples was observed. Migration tests of CPs in plastic bottles showed essentially no migration into honey during storage. The risks to humans from CPs in honey are low.
Show more [+] Less [-]Is mulch film itself the primary source of meso- and microplastics in the mulching cultivated soil? A preliminary field study with econometric methods
2022
Xu, Li | Xu, Xiangbo | Li, Chang | Li, Jing | Sun, Mingxing | Zhang, Linxiu
There has been an increasing interest in the pollution caused by meso- and microplastics (MMPs) in terrestrial ecosystems. Mulch film was once considered to be the most important source of MMPs in the mulching cultivated soil. However, the academic community has not given sufficient scientific evidence. In this study, stratified random sampling method was used to selectively interview households in Hebei province, China (400 households, 20 villages, 5 counties). Finally, household characteristics and mulch film use behavior of 41 households were collected, and corresponding soil samples were sampled. The results showed that 1) the abundance of MMPs was 29.3 ± 33.1 items·kg⁻¹ (DW) and the particle size of MMPs was 2.95 × 10³±1.75 × 10³ μm, and the proportion of MMPs derived from Polyethylene (PE) was only 18.8%; 2) the mass of MMPs was 2.90 ± 3.72 mg kg⁻¹ (DW) and the proportion of PE MMPs was 43.75%, which has the highest mass percentage; 3) After controlling the endogenous and dummy variables, the use history of mulch film (HistMF) was found to be positively correlated to the abundance of MMPs and inversely correlated to the particle size, but nor with the mass of MMPs; 4) Regarding the heterogeneous characteristics of MMPs, including particle size, color, shape, and type, the findings found the absence of a significant correlation between HistMF and the abundance and mass of PE. In summary, mulch-derived MMPs are not the primary source of MMPs in the mulching cultivated soil in terms of abundance but probably be in terms of mass.
Show more [+] Less [-]Organophosphate esters in surface waters of Shandong Peninsula in eastern China: Levels, profile, source, spatial distribution, and partitioning
2022
Lian, Maoshan | Lin, Chunye | Xin, Ming | Gu, Xiang | Lü Shuang, | Wang, Baodong | Ouyang, Wei | Liu, Xitao | He, Mengchang
Organophosphate ester (OPE) levels, profiles, sources, spatial distribution, and partitioning were firstly studied in the rivers of the Shandong Peninsula. A total of 53 water samples and 45 sediment samples were collected from the rivers and the sewage treatment plant in the peninsula to quantitate levels of 13 targeted OPEs. Total OPE concentrations ranged from 263 to 6676 ng L⁻¹ in the water, and 39.3–360 ng g⁻¹ in the sediment. TEP, TCPP, and TCEP together contributed more than 90% of total OPE content. TCEP and TCPP concentrations in the Xiaoqing River sediment were increased by approximately two and seven times from 2014 to 2019, respectively. Total OPE concentrations generally increased from upstream regions to the estuaries. The main OPE sources were municipal effluent in the Jiaozhou Bay (JZB) watershed and chemical industrial wastewater in the Laizhou Bay (LZB) watershed. TCPP, TEP, and TCEP were generally approaching equilibrium between sediment and overlying water, while TNBP, TIBP, and TBOEP effectively transferred from the overlying water to the sediment. The riverine OPE flux was 0.66 ton/year to JZB and 3.58 ton/year to the LZB. TCPP and TCEP in municipal effluent, and TEP in chemical industrial wastewater should be regulated to protect Shandong Peninsula waters.
Show more [+] Less [-]Source apportionment of potentially toxic elements in soils of the Yellow River Delta Nature Reserve, China: The application of three receptor models and geostatistical independent simulation
2021
Zhang, Mengna | Lv, Jianshu
The Yellow River Delta (YRD) wetland, the most important estuary wetland in eastern China, has an important ecosystem service function. Rapid and intensive development has inevitably led to the accumulation of potentially toxic elements (PTEs) in soils. Therefore, identifying quantitative sources and spatial distributions of PTEs is essential for soil environmental protection in the YRD. A total of 240 topsoil samples (0–20 cm) were collected in the Yellow River Delta Nature Reserve (YRDNR) and analyzed the PTE contents. To avoid the biases of the single receptor model, positive matrix factorization, factor analysis with nonnegative constraints, and maximum likelihood principal component analysis-multivariate curve resolution-alternating least squares were used for source apportionment of soil PTEs. To promote the efficiency of multivariate geostatistical simulation, a minimum/maximum autocorrelation factor-sequential Gaussian simulation was built to map the spatial patterns of PTEs. Three factors were derived by the three receptor models, and their contributions to the source explanation were similar. As, Cr, Cu, Mn, Ni, and Zn originated from natural sources, with contributions of 85.6%–96.4 %. A total of 61.5 % of Hg was associated with atmospheric deposition of coal combustion and wastewater from upstream. Agricultural activities and oil exploitation contributed 33.5 % and 15.9 % of the Cd and Pb concentrations. Spatial distributions of soil PTEs were controlled by sedimentary grain size. A total of 47.2 % of the total study area was identified as hazardous area for Cd, 10.3 % for As, and 5.4 % for Hg. This work is expected to provide references for soil pollution assessment and management of YRDNR.
Show more [+] Less [-]Cadmium source identification in soils and high-risk regions predicted by geographical detector method
2020
Zhao, Yinjun | Deng, Qiyu | Lin, Qing | Zeng, Changyu | Zhong, Cong
Cadmium (Cd) contamination in soils has become a serious and widespread environmental problem, especially in areas with high natural background Cd values, but the mechanism of Cd enrichment in these areas is still unclear. This study uses the Guangxi Zhuang Autonomous Region (Guangxi), a typical area with a high background Cd level and Cd pollution related to mining activities, as an example to explore the source and predict areas with high Cd risk in soils based on the geographical detector method. The areas with high Cd in Guangxi soils were classified into non-mining areas and mining areas according to their potential Cd sources. The results show that the rich Cd content in the soils from the non-mining area of Guangxi was mainly derived from the soil type (q = 0.34), geological age (q = 0.27), rock type (q = 0.26) and geomorphic type (q = 0.20). Specifically, the Cd content was derived from the weathering and deposition processes of carbonatite from the Carboniferous system in the karst area. The high Cd content in the soils of the mining area of Guangxi was mainly derived from the area mined for mineral resources (q = 0.08) and rock type (q = 0.05). Specifically, the Cd content was derived from the mining of lead-zinc ores. The areas in Guangxi with a high risk of Cd soil pollution are mostly concentrated in karst areas, such as Hechi, Laibin, Chongzuo, southern Liuzhou and Baise, northern Nanning city and northeastern Guilin city, and some mining areas. These results indicated that the high Cd concentration in the soils of large areas of Guangxi is probably due to natural sources, while the high Cd concentration around mining areas is due to anthropogenic sources. The results will be useful for soil restoration and locating and controlling contaminated agricultural land.
Show more [+] Less [-]Wet deposition and sources of inorganic nitrogen in the Three Gorges Reservoir Region, China
2018
Wang, Huanbo | Shi, Guangming | Tian, Mi | Chen, Yang | Qiao, Baoqing | Zhang, Liuyi | Yang, Fumo | Zhang, Leiming | Luo, Qiong
Precipitation samples were collected at five rural and one urban sites in the Three Gorges Reservoir Region (TGR), China from March 2014 to February 2016. The inorganic reactive nitrogen (Nr) contents were analysed to investigate their wet deposition flux, budget, and sources in the area. Annual Nr wet deposition varied from 7.1 to 23.4 kg N ha⁻¹ yr⁻¹ over the six sites during the two-year study campaign. The six-site average Nr wet deposition flux was 17.1 and 11.7 kg N ha⁻¹ yr⁻¹ in 2014 and 2015, respectively, with 71% from NH₄⁺ and 29% from NO₃⁻. Dry deposition flux was estimated using the inferential method, which combined the measured ambient concentrations and modelled dry deposition velocities. The total (dry + wet) Nr deposition fluxes were estimated to be 21.4 kg N ha⁻¹ yr⁻¹ in 2014 and 16.0 kg N ha⁻¹ yr⁻¹ in 2015 at rural sites, and 31.4 and 25.3 kg N ha⁻¹ yr⁻¹ at the urban site. Annual average volume weighted mean (VWM) concentrations in precipitation at all the six sites differed little for NO₃⁻ but up to a factor of 2.0 for NH₄⁺ with the highest value at the urban site. Industrial emissions, agricultural emissions, soil dust, and biomass burning were identified as potential sources of the major inorganic ions in precipitation using factor analysis and correlation analysis. Conditional probability function (CPF) analysis indicated that the urban site was predominantly affected by industrial emissions from a power plant, cement manufactory, and salt chemical facility located ∼13 km southeast of the sampling site.
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