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71.
将城市污泥应用于生态恢复因能避开粮食作物食物链而具有良好前景,但其对地表水环境影响仍不十分清楚.本文将城市污泥与建筑垃圾按1∶1体积比混合为生长基质,覆盖在模拟的煤矸石边坡上,播种8种乡土木本植物,对生长季植物生长情况以及坡面地表水和下渗水的电导率、p H、氮磷钾、重金属、多环芳烃等含量进行分析.结果表明:坡面植物生长良好,平均覆盖度达60%;地表水和下渗水的p H值近中性,变化不大,而电导率、氮磷钾、重金属和多环芳烃含量均较高,其中,氮、磷含量在整个生长季超过国家地表水环境质量Ⅴ类水质标准;7月重金属含量最高,其中,As含量只达地表水环境质量Ⅳ~Ⅴ类标准,其余重金属含量多达Ⅱ~Ⅳ标准;随着夏季雨水淋洗增加以及植物-土壤系统对化学物质的吸收、降解和固着作用,地表水和下渗水的电导率、氮磷钾、重金属和多环芳烃含量均显著下降,生长季后期重金属含量达到地表水环境质量Ⅱ~Ⅲ类标准,多环芳烃含量减少约一半.将城市污泥直接应用在煤矸石边坡生态恢复中有利于植物生长,植物-土壤系统使得生长基质中的有害物含量逐渐降低,对地表水环境的负影响主要表现为氮、磷的富营养化,但总体上其环境安全性可控.  相似文献   
72.
Baligar  V.  He  Z.L.  Martens  D.C.  Ritchey  K.D.  Kemper  W.D. 《Plant and Soil》1997,195(1):129-136
Remediation of soil acidity is crucial for increasing crop production and improving environmental quality of acid infertile soils. Soil incubation and greenhouse pot experiments were carried out to examine the interactions between phosphate rock (PR), coal combustion by-product (BP), dolomitic lime (L), and cellulose (C) in an acidic soil and their effects on ryegrass (Lolium perenne L. cv Linn) growth. BP and PR application increased plant P content and dry matter yield (DMY) of shoots and roots by improving soil Ca availability and reducing Al toxicity. Application of BP at low rates (5 to 10 g BP kg-1) with PR appeared to decrease both plant P content and DMY compared to PR application alone. The reduced DMY is due to an increased Al concentration in soil solution as a result of displacement of sorbed Al by Ca of BP. Increases in DMY were obtained by addition of lime along with PR and BP at low rates or by increasing BP application rates above 15 g kg-1. This improved plant response was likely related to alleviation of Al toxicity by CaCO3 contained in the BP. In addition to raising the pH to an acceptable level for plant growth, the dolomitic lime supplied needed Mg for plants, thereby maintaining a good balance between available Ca and Mg for plants in the BP- and PR-amended soils. The addition of cellulose to the BP- and PR-amended soils reduced water-soluble Al and increased DMY. Plant growth increased PR dissolution by 2.4 to 243% in a soil with low available P. Use of BP at moderate rates with PR and dolomitic lime appears to be the best combination in increasing crop yields on infertile acidic soils.  相似文献   
73.
Abstract. Shoot and root biomass yield of a sown grass, Pennisetum pedicellatum, were measured at below-canopy, canopy edge and open locations in young monoculture stands of eight tree species planted on a coalmine spoil. Incident light as percentage of full sunlight decreased from open to canopy edge to below-canopy locations. The shoot and root weights of Pennisetum in different tree stands for each of the three locations were significantly different and were significantly related to each other, and to percentage sunlight across all tree species plots and locations. The gradient of incident light was the principal factor governing the gradient of grass biomass under developing canopies of tree plantations on the mine spoil.  相似文献   
74.
Heavy metals enrichment in groundwater poses great ecological risks to human beings. In the present research work, a total of 59 groundwater samples from 12 sampling points in Dingji coal mine, Huainan coalfield, were collected and measured for Cu, Pb, Zn, Cd, Ni, Mn, Cr, and Fe by inductively coupled plasma mass spectrometry (ICP-MS). The human health risk caused by heavy metals through the pathway of drinking water was evaluated and analyzed using the US Environment Protection Agency (USEPA) evaluation model. It has been found that the carcinogenic risk values were between 1.05 × 10?5 and 3.5 × 10?4, all exceeding the maximum acceptable level recommended by the USEPA, and the carcinogenic risk of Cr accounted for 99.67% of the total carcinogenic risk. The non-carcinogenic health risk values were all lower than the negligible level given by the USEPA, and the contribution of non-carcinogenic health risk was in the order of Cr > Zn > Cu / Pb >Mn > Fe > Cd > Ni. Among them, Cr had the largest contribution, accounting for 36% of the total non-carcinogenic risk value. In this study, the carcinogenic risk constituted 99.99% of the total health risk, indicating that the total health risk essentially consisted of carcinogenic risk. The research results suggest that much more attention should be paid to the health risk caused by Cr in the groundwater.  相似文献   
75.
This research was conducted to assess the water quality and the contamination of heavy metals in water, sediment, fish, and frogs, as well as bioaccumulation factors (BAFs) in fish and frogs around the gold mine area. The water samples were analyzed for water quality (temperature, pH, and dissolved oxygen). The samples were analyzed for heavy metals by inductively coupled plasma optical emission spectrometry. The water quality was within the standard. The concentrations of heavy metals, including As, Cr, Cd, Pb, Ni, Zn, Fe, Mn, and Cu, in water and sediment samples were measured. Three species of fish were collected: Rasbora tornieri, Brachydanio albolineata, and Systomus rubripinnis. The mean heavy metal concentrations of fish were as follows: Fe>Zn>Mn>Cr>Ni>Cu>As>Pb>Cd. The As, Cr, and Pb concentrations in all the fish species exceeded the standard levels. Five species of frogs were collected: Kaloula pulchra, Microhyla heymonsi, Fejervarya limnocharis, Hoplobatrachus rugulosus, and Microhyla pulchra. The mean heavy metal concentrations of frog were as follows: Fe>Cu>Mn>Zn>Cr>Ni>Pb>Cd>As. The Cr, Cd, and Cu concentrations exceeded the standard levels. The BAFs in fish were in order of Cr>Zn>Ni>Cu>Pb>Fe>Cd>As. The BAFs in frogs were Cr>Zn>Ni>Cu>Fe>Pb>Cd>As. The accumulation of heavy metals was higher in the sediment than in the water. Many aquatic organisms take up heavy metals directly from the environment around the gold mine.  相似文献   
76.
77.
Hartmann  R.  Schneider  B. U.  Gast  C.  Keplin  B.  Hüttl  R. F. 《Plant and Soil》1999,213(1-2):99-115
The effects of a slow-release N-enriched rock powder on soil chemistry, on the development of the soil vegetation (field layer vegetation), on the nutritional status of pine seedlings (Pinus sylvestris L.), and on decomposition rates of cellulose in lignite-poor mine spoils were studied. In the initial phase after afforestation fertilization caused a significant increase in NO3 -N concentrations in the soil solution of the top-soil (0–60 cm). Subsequently, NO3 -N concentrations of all N fertilized treatments decreased with the exception of the highest N application area (500 kg N ha−1). This decrease of NO3 -N concentrations was related to the establishment of a field layer vegetation, which developed according to the amount of N applied. In the above-ground phytomass of the field layer vegetation a maximum N accumulation amount of 22 kg ha−1 was measured. Cellulose decomposition increased with higher N application rates. In the second year after N-fertilization, the pine needles indicated insufficient supply for almost all nutrients except for N. The deficiency symptoms were most pronounced at the plots that had received the highest amounts of nitrogen. This phenomenon appears to be related to the competition by the field layer vegetation. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
78.
Kielhorn  K. -H.  Keplin  B.  Hüttl  R. F. 《Plant and Soil》1999,213(1-2):117-125
On a study site in the Lusatian lignite mining region (Germany), sandy mine spoil was ameliorated with either sewage sludge, compost or mineral fertilizer. Plots were sown with the grass Secale multicaule and planted with pine seedlings except for a control that was not meliorated and not revegetated. Pitfall catches of ground beetles in 1996/97 yielded high numbers of species and individuals directly after revegetation. The dominant beetles were xerophilic species, known to prefer open sandy sites. Catches in different plots were positively correlated with the amount of vegetation cover and declined as follows: amelioration with sewage sludge > compost > mineral fertilizer > untreated control. Even beetles characteristic of open sandy sites showed a distinct preference for plots with high vegetation cover treated with organic waste. For the dominant species, an attraction to shelter and a more balanced, humid microclimate is assumed. A year-to-year comparison showed an increase in beetles typical of dry grasslands and ruderal sites in the second year, while characteristic species of open sandy sites decreased. Application of organic waste combined with revegetation led to an immediate increase in beetle numbers. In the long term, revegetation would be expected to reduce suitable habitats for endangered ground beetles which prefer open sites with poor sandy soils. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
79.
The types of plant communities in Mengentaoligai mine area are disscussed. Arenaria juncea, densely grown in the phytocommunities of the mineralized zone, is found closely related to the presence of Pb and Zn mineral deposits. Analytical results of seven element contents (in ash) for 34 species (or part of plant) show that: levels of element contents in sequence in. the plants are Fe>Mn > Zn > Pb > Cu > Ni>Co; variable ranges of element contents in the plants are Pb, Zn>Fe,Mn> Cu> Co > Ni; and variable ranges of Pb, Zn contents in the same species at different sites are respectively larger than that among species. For example, Pb and Zn contents of Arenaria juncea, l145ppm and 3087ppm respectively, are the highest; the difference among Pb contents of Ulmus macrocarpa, Arenaria ?uncea and PotentiUa chinensis at different sites are more than 10 folds. The difference of Co and Ni contents in the species is less than two to one- Striking correlation is found between elements in plants and in soils, such as the Pb and Zn contents between leaves and twigs of Ulmus macrocarpa, twigs of Prunus sibirica, Artemisia halodendron and soils (lrl≤α 0.05 or≤α 0.01). It is found that Pb and Zn phytogeochemical anomalies, correlate closely with Pb and Zn mining deposits. In addition, analysis of principal component was conducted among seven elements contents of 14 species (or part of plant) in the mineralized zone and 12 species in the unmineralized zone.  相似文献   
80.
基于NDVI时间序列轨迹的草原露天矿区植被时空动态特征   总被引:1,自引:0,他引:1  
贾铎  王藏姣  牟守国  赵华 《生态学杂志》2017,28(6):1808-1816
采矿作用下草原露天矿区植被时空动态特征尚不明确.以胜利露天矿区为例,选取MODIS和Landsat影像,利用ESTARFM构建2001—2015年植被生长期一致的年际Landsat时间序列,以时间分割算法拟合像元NDVI时间序列轨迹,结合轨迹形态特征提取早期扰动型、持续扰动型、扰动稳定型、扰动稳定恢复型和扰动恢复型5种植被动态类型及各类型的时间特征.结果表明:胜利矿区植被动态类型以扰动恢复型为主,占各类型像元总数的55.2%,扰动稳定型和持续下降型次之,分别为25.6%和11.0%,早期扰动型和扰动稳定恢复型较小,分别为3.5%和4.7%.扰动多发于2004—2009年,稳定期多始于2008年,空间上多分布于露天采场和排土场,恢复期多始于2008年和2010年,其空间范围较小且集中于矿井外围和排土场.扰动持续时长以1年为主,稳定期持续时长以7年为主,恢复期持续时长中稳定恢复型为2~5年,扰动恢复型为8年.  相似文献   
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