| 2. |
- Liang, Jiawei, et al.
(författare)
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Performance and microbial communities of a novel integrated industrial-scale pulp and paper wastewater treatment plant
- 2021
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 278
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Tidskriftsartikel (refereegranskat)abstract
- Ltd Paper production generates pulp and paper wastewater (PPW), and it is difficult to remove the high-level pollutants in PPW efficiently. Herein, an efficient industrial-scale pulp and paper wastewater treatment plant (PP-WWTP) that integrated physicochemical and biological processes is investigated and reported. This PP-WWTP treated 2.3 Mt of wastewater with 17,388 ± 1436 mg/L chemical oxygen demand (COD) annually. The PP-WWTP can effectively remove over 99.81% of the COD. In detail, the physical, anaerobic, aerobic and chemical steps accounted for 41.6%, 40.0%, 11.9%, and 6.5% of COD removal, respectively. The microbial communities of the bioreactors removed the pollutants efficiently and contained diverse microbes. Further metagenomic analyses of the bioreactors identified more than 90,000 genes/gene fragments encoding for carbohydrate-active enzymes (CAZys), demonstrating high lignocellulose degradation ability of the bioreactors at molecular level. The xylanase activity assay showed some lignocellulase in the bioreactors were functional. Recycling the residual heat from the PPW along with energy recovered from biological treatment of the PPW, in the form of biogas (20,000 m³/d), could generate more than 1.5 M USD benefits/y. The results of this study demonstrated that the integrated physicochemical and biological process for PPWW treatment could effectively remove pollutants while generating revenue.
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| 3. |
- Zheng, Kaiyuan, et al.
(författare)
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Impacts of climate change and anthropogenic activities on vegetation change : Evidence from typical areas in China
- 2021
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Ingår i: Ecological Indicators. - : Elsevier BV. - 1470-160X. ; 126
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the interactions of climate-vegetation and human-vegetation has been a critical issue and increasingly attracting attention from scientific community in the field of global change research. This study investigated the heterogeneous impacts of climate change and anthropogenic activities on vegetation change by applying the trend analysis and Geodetector approach. The spatial and temporal patterns of MODIS NDVI and LAI during 2003–2017 were firstly examined in China. We then quantified the contribution and interactions effects of climatic factors (temperature and precipitation) and anthropogenic factors (population, gross domestic product and other four categories of forestry investment) on vegetation change in five typical areas of China. Both NDVI and LAI across China demonstrated a significant increasing trend over the past two decades. However, the eastern developmental regions such as Beijing-Tianjin-Hebei Region and Yangtze River Delta exhibited a decreasing trend due to fast urbanization. Socio-economical inputs (the explanatory power of forestry investment > 40%, the range of explanatory power is 0 to 100%) were identified as the dominant driving forces of vegetation change for the most of study areas. Precipitation was the most important natural influencing factor of vegetation change. We also found that the interactions between forestry investment and other factors presented much greater explanatory power on vegetation change than a single factor. Our research highlights that the afforestation program in China during the past several decades plays an important role in contributing to vegetation greening across the country. Greening and degradation, however, are largely related to landscape context, which could be due to natural change and anthropogenic impact. To maintain high levels of forests, conserving the vegetation is more important than increasing the economic development.
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