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11.
The structure of coastal land cover in Estonia is intricate and exhibits considerable differences from site to site. The diverse geomorphology of the seashores is one of the key factors affecting the speed and magnitude of land cover changes. Likewise, the history of human inhabitance on the coast has also shaped the character of land cover. The Estonian coastal zone has experienced abrupt and radical changes in land ownership and its related land use during the last century. The main objectives of this paper are: 1) to give an overview of land use and the trends of development of land cover pattern along different parts of the Estonian coast; and 2) to analyze the relationships of natural and human processes and their cumulative impact on the evolution of coastal land cover pattern in Estonia. This study is based on results obtained during fieldwork in the study areas and on the analysis of large-scale (1:10,000) historical maps. In agriculturally dominant coastal areas, the traditional open landscape of fields and grassland at the beginning of the 20th century had been replaced by woodland and grasslands with shrubs by the start of the 21st century. Expansion of reed beds in areas of former seashore grasslands is another striking phenomenon. The structure of land cover on forested coasts has been fairly stable during the last 100 years. Areas of urban sprawl are characterised by dramatic changes in land cover structure. Rapidly increasing population and expanding settlements imposes on the ecological balance of the fragile dune forests in the coastal zone.  相似文献   
12.
The classical use of synthetic dyes is causing issues of environmental pollution and heath risk. As a consequence natural dyes are gaining interest, but the use of natural dyes still includes toxic reagents such as metals as mordants and acids to enhance color and yield. Therefore, we designed a new chitosan-polypropylene imine dendrimer hybrid at 0–2000 mg/L to treat wool before dyeing with cochineal. We compared dye exhaustion, color depth, color characteristics, and color fastness of the new process with dyed pristine and metal mordanted wool. Results show that wool pretreatment improved dye exhaustion from 48 to 88 %, shifted saturation point toward lower dye concentration from 3000 to 1000 mg/L, and improved color depth from 13.68 for pristine wool and 15.17 for metal mordanted wool to 23.89 for the new process.  相似文献   
13.
Environmental Science and Pollution Research - The concentrations of major and trace elements in the sediments from the Four River inlets of Dongting Lake were analysed. The results show that the...  相似文献   
14.
Environmental Science and Pollution Research - For effective photocatalytic pollutant degradation on bismuth tungstate (Bi2WO6), it is vital to enhance the photogenerated charge separation and the...  相似文献   
15.

Characterization of the typical petroleum pollutants, polycyclic aromatic hydrocarbons (PAHs) and n-alkanes, and indigenous microbial community structure and function in historically contaminated soil at petrol stations is critical. Five soil samples were collected from a petrol station in Beijing, China. The concentrations of 16 PAHs and 31 n-alkanes were measured by gas chromatography-mass spectrometry. The total concentrations of PAHs and n-alkanes ranged from 973 ± 55 to 2667 ± 183 μg/kg and 6.40 ± 0.38 to 8.65 ± 0.59 mg/kg (dry weight), respectively, which increased with depth. According to the observed molecular indices, PAHs and n-alkanes originated mostly from petroleum-related sources. The levels of ΣPAHs and the total toxic benzo[a]pyrene equivalent (ranging from 6.41 to 72.54 μg/kg) might exert adverse biological effects. Shotgun metagenomic sequencing was employed to investigate the indigenous microbial community structure and function. The results revealed that Proteobacteria and Actinobacteria were the most abundant phyla, and Nocardioides and Microbacterium were the important genera. Based on COG and KEGG annotations, the highly abundant functional classes were identified, and these functions were involved in allowing microorganisms to adapt to the pressure from contaminants. Five petroleum hydrocarbon degradation-related genes were annotated, revealing the distribution of degrading microorganisms. This work facilitates the understanding of the composition, source, and potential ecological impacts of residual PAHs and n-alkanes in historically contaminated soil.

  相似文献   
16.
Environmental Science and Pollution Research - Mechanical vapor compression and multi-effect evaporation have been widely used in achieving zero discharge of desulfurization wastewater as they are...  相似文献   
17.
Environmental Science and Pollution Research - In the process of coal gangue surface accumulation and underground filling disposal, the heavy metals contained in coal gangue will inevitably...  相似文献   
18.
Journal of Material Cycles and Waste Management - This study aimed at investigating the impacts of different percentages of biochar (BC) (at 0, 15, and 25%; by vol.) and/or cattle manure (CM) (at...  相似文献   
19.
Environmental Science and Pollution Research - In this study, porous activated carbon balls supported by nanoscale zero-valent iron composites (Fe@PACB-700) were used for the first time for the...  相似文献   
20.
Efficient removal of chlorine from PVC achieved by two-stage heat-treatment (280 and 410 degrees C) provided chlorine-free isotropic pitch containing additive. The pitch was stabilized and carbonized into porous carbons with surface areas of approximately 300 m2/g. Resultant porous carbons showed three pore structures of supermicropore, micropore and mesopore. The generation of CO2 from the decomposition of the CaCO3 additive in waste PVC is responsible for the development of porous structures. The surface area of the carbonized product increased after the removal of CaO.  相似文献   
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