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561.
Recovering the Reptile Community after the Mine-Tailing Accident of Aznalcóllar (Southwestern Spain)
Rocío Márquez-Ferrando Juan M. Pleguezuelos Xavier Santos Diego Ontiveros Juan R. Fernández-Cardenete 《Restoration Ecology》2009,17(5):660-667
Ecosystem restoration requires that habitat requirements of all species be considered. Among animal communities in Mediterranean ecosystems, reptiles, as ectothermic vertebrates, need refuges for avoidance of extreme environmental temperatures, concealment from predators, and oviposition sites. In 1998, a massive amount of tailings broke out of the holding pond of the Aznalcóllar mine (southwestern Spain) and polluted the Guadiamar river valley. After the accident, a soil- and vegetation restoration program began, and the Guadiamar Green Corridor was created to connect two huge natural areas, Doñana National Park and the Sierra Morena. Within this corridor, the reptile community remained dramatically impoverished, probably because of elimination of all natural refuges during the soil restoration program. To test this hypothesis, we set an array of artificial refuges (logs) in a large experimental plot. During the 5 years of the experiment (2002–2006), the area managed with artificial refuges exhibited a better and faster recovery of the reptile community in species richness and individual abundance than did the control area with no artificial refuges. Moreover, reptile colonization of the Guadiamar Green Corridor was transverse rather than lineal—that is, it did not act as a corridor for reptiles, at least in the first stages of colonization. This suggests that landscape restoration programs should not neglect refuge availability, a limiting resource for reptile species. 相似文献
562.
Nursery Nitrogen Loading Improves Field Performance of Bareroot Oak Seedlings Planted on Abandoned Mine Lands 总被引:2,自引:0,他引:2
Although mine reclamation sites are important targets for ecological restoration, they are generally difficult to regenerate successfully. We evaluated the importance of nursery nutrient loading as a new approach to enhance forest restoration on abandoned mine lands. Northern red oak ( Quercus rubra ) and White oak ( Q. alba ) seedlings were nitrogen (N) loaded for 18 weeks at a bareroot nursery in southern Indiana, United States. Fertility treatments followed conventional or modified exponential functions to synchronize N supply with plant demand. Subsequently, nursery-grown seedlings were outplanted the following year onto a mine reclamation site in southwestern Indiana to evaluate effects of nursery N loading on first-year field performance. Nursery N loading promoted total plant dry mass production 25–129% in Red oak and 50–184% in White oak compared to unfertilized plants. Nitrogen loading increased N content 88–145% and potassium (K) content 16–71% for Red oak and N content 124–250% and K content 16–93% for White oak relative to controls. When outplanted, N loading resulted in high seedling survival (>84%) and increased total plant dry mass production 14–30% for Red oak and 23–52% for White oak. Nitrogen loading increased plant N uptake 14–102% in Red oak and 32–105% in White oak under field conditions. Exponential N loading demonstrates potential as a viable technique to improve seedling outplanting performance and reclamation success in Indiana and elsewhere. 相似文献
563.
Safety Risk Assessment of Iran's Underground Coal Mines Based on Preventive and Preparative Measures
Mining is one of the most hazardous occupations all around the world, especially in underground coal mines. Analysis and management of safety risk are prerequisites toward control and increment in mines' safety. Common safety risk analyses in mines are based on the statistical data of the occurred incidents and economical aspects are usually neglected. In this study, based on a novel procedure and presentation of preventive and preparative measures, safety risk of Iran's underground coal mines' incidents was assessed and classified by taking advantage of Iran's mining experts' opinions. Among 10 significant identified incidents, methane explosion, coal dust explosion, and traffic accidents accounted for the highest levels of safety risk before adjustment, respectively. The most hazardous incidents in the adjusted risk mode were the same, but in a reverse order. Application of safety measures in three modes of preventive adjustments, preparative adjustment and both of them caused some risk reduction with the mean values of 67, 21, and 75%, respectively, thereby indicating the importance of safety risk management in underground coal mines and the preference for preventive measures in this area. 相似文献
564.
565.
Acid mine drainage is a widespread environmental problem and is characterized by elevated proton, sulfate, and dissolved iron concentrations. To understand the driving forces behind the attenuation of AMD, we compared microcosms using sediment and groundwater collected at Davis Mine, Massachusetts, a site where both generation and attenuation of AMD occur. A shift in key geochemical parameters over time was due to the natural microbial population, which was supported by detailed molecular biology results. The attenuation of AMD was stimulated through amendment with glycerol, with nitrogen and phosphorous, or with algae extract, but not by wood chips, suggesting the addition of different organic electron donors as a bioremediation strategy. 相似文献
566.
淮北采煤塌陷区小型湖泊浮游植物群落结构和季节动态 总被引:1,自引:0,他引:1
深入了解煤矿塌陷湖泊生态系统的结构与功能,有助于开展淮北煤矿塌陷水域的生态保护和资源的可持续利用。该文从2005年3月至2007年2月,研究了淮北采煤塌陷区两个小型湖泊(南湖和乾隆湖)浮游植物的群落结构和季节动态。结果表明:乾隆湖中总氮和总磷的浓度均高于南湖。蓝藻和绿藻均为南湖和乾隆湖的优势类群,其总和分别约占两湖泊年平均总浮游植物生物量的69.8%和63.3%,且南湖浮游植物生物量明显低于乾隆湖。另外,南湖夏季出现了以铜绿微囊藻(Microcystis aeruginosa)为主的蓝藻水华,而富营养湖泊中常见的微囊藻属(Microcystis)和水华束丝藻(Aphanizomenon flos-aquae)等蓝藻种类在乾隆湖中没有被观察到。除营养盐、温度外,鱼类和硬度水质可能是影响淮北采煤塌陷区小型湖泊浮游植物群落演替和生物量季节变化的重要原因。 相似文献
567.
Víctor Gabari 《人类与生态风险评估》2017,23(8):2069-2086
A risk-based corrective action (RBCA) approach was conducted to assess the potential health risks associated with occupational and environmental exposures to trace elements in cultivated mine soil, reporting a site-specific environmental health and safety case study in the Spanish sector of the Iberian Pyrite Belt. The median concentrations of As in soil (580 mg kg?1), Cu (635 mg kg?1), Pb (2100 mg kg?1), and Zn (270 mg kg?1) largely exceeded the regional geochemical baseline, reaching values above which adverse health effects may potentially occur. The results of the RBCA analysis suggest the possibility that a median carcinogenic risk (9.3E-04) may be associated to arsenic exposure by ingestion and dermal contact pathways. In addition, the median hazard index was more than four times higher than the acceptable risk level, with As (hazard quotient value of 3.3) being also the largest single contributor to the overall non-carcinogenic risk. However, no detrimental health effects are expected to occur through inhalation of soil particles in people living near the source zone. Preventive measures should be applied to reduce surface soil exposure in the light of the results achieved. 相似文献
568.
我国西北干旱荒漠区生态环境脆弱,煤炭开采活动严重地破坏植被和影响生态环境,而煤炭井工开采对干旱荒漠区植被动态变化的影响尚不明确。以灵武市为例,采用遥感技术和野外实地调查相结合的方法,分析2000-2019年间煤炭井工开采对植被动态变化的影响。结果表明:灵武市的植被主要以沙蒿(Artemisia salsoloides)、柠条(Caragana korshinskii)和芨芨草(Achnatherum splendens)等荒漠植物为主;2000-2019年间,植被覆盖度(FVC)和绿度变化率(GRC)表明灵武市植被整体呈现改善趋势;归一化植被指数(NDVI)与年降水量(P)和年平均风速(S)等气象因子显著相关,表明气候因子对区域植被动态变化起主要作用;煤炭开采区侵占草地和灌丛面积,使得土地利用类型发生变化,生态环保政策的实施对于区域土地利用类型的变化和植被改善具有重要作用。实地调查分析表明煤炭开采改变了矿区植物群落结构,植被盖度和物种多样性指数均在煤炭开采后1-4a呈下降趋势,5-9a为上升趋势,10a自然恢复后与对照区的变化趋势一致,说明在自然条件下煤炭开采区植被恢复经历了退化期、改善期和初步恢复期等过程。这些研究结果为西北干旱荒漠区煤炭井工开采矿区植被恢复和生态环境建设提供了理论基础。 相似文献
569.
570.
Effects of mine acid on longevity and reproductive rate of the parthenogenic gastrotrich Lepidodermella squammata were studied under laboratory culture conditions. Water from unpolluted and polluted streams was used, directly or mixed, to establish a series of test conditions at pH 8.1, 7.1, 6.4, 5.2, 4.6 and 3.3. Eggs, cultured individually under each test condition, were observed at 12 h intervals for hatching, daughter egg laying and death. Data representing 50 animals under each test condition were used in the construction of a series of life tables. From these were calculated maximal life expectancy (ex), net reproductive rate per individual lifetime (Ro) and intrinsic rate of natural increase (rmax).Values of ex, Ro and rmax were maximal at pH 7.1 and were reduced slightly at the higher pH; ex was greatly reduced and Ro zero at pH 6.4 and 5.2; and ex was zero at pH 4.6 and 3.3. Analysis of variance tests indicate significant differences between ex values of L. squammata cultured at pH 8.1 and those cultured at pH 7.1, but no differences between Ro or rmax.Associated with the decrease in pH was an increase in total conductivity and a decrease in carbonate alkalinity and hence in carbonate conductivity. It appears that L. squammata is capable of living and reproducing at pH 6.0 to 6.5 under field conditions low in carbonates, providing non-carbonate ions are not abundant, or under field conditions high in non-carbonate ions, providing sufficient carbonates are present. 相似文献