作者机构：
[Jin M. Triolo; Sven G. Sommer] Univ So Denmark, Fac Engn, Inst Chem Engn Biotechnol & Environm Technol, DK-5230 Odense M, Denmark.;[Moller, Henrik B.] Aarhus Univ, Fac Agr Sci, Dept Biosyst Engn, Res Ctr Foulum, DK-8830 Tjele, Denmark.;[Martin R. Weisbjerg] Aarhus Univ, Fac Agr Sci, Dept Anim Hlth & Biosci, DK-8830 Tjele, Denmark.;[Xin Y. Jiang] Cent S Univ Forestry & Technol, Coll Mat Sci & Technol, Changsha 410004, Hunan, Peoples R China.;[Jin M. Triolo] Univ So Denmark, Fac Engn, Inst Chem Engn Biotechnol & Environm Technol, Niels Bohrs Alle 1, DK-5230 Odense M, Denmark.
通讯机构：
[Triolo, Jin M.] Univ So Denmark, Fac Engn, Inst Chem Engn Biotechnol & Environm Technol, Niels Bohrs Alle 1, DK-5230 Odense M, Denmark.
关键词：
Biogas;Digestibility;Lignin;Lignocellulose;Predicting methane production potential
摘要：
We examined the influence of fibrous fractions of biomass on biochemical methane potential (BMP) with the objective of developing an economical and easy-to-use statistical model to predict BMP, and hence the biodegradability of organic material (BD) for biogas production. The model was developed either for energy crops (grass, maize, and straw) or for animal manures, or as a combined model for these two biomass groups. It was found that lignin concentration in volatile solids (VS) was the strongest predictor of BMP for all the biomass samples. The square of the sample correlation coefficient (R(2)) from the BMP versus lignin was 0.908 (p < 0.0001), 0.763 (p < 0.001) and 0.883 (p < 0.001) for animal manure, energy crops and the combined model, respectively. Validation of the combined model was carried out using 65 datasets from the literature. (C) 2011 Elsevier Ltd. All rights reserved.
关键词：
carbon budget;ice retreat;intact ecosystems;land use change;permafrost
摘要：
With a pace of about twice the observed rate of global warming, the temperature on the Qinghai‐Tibetan Plateau (Earth's ‘third pole’) has increased by 0.2 °C per decade over the past 50 years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming‐induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process‐based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles.
作者：
Jiang, Xinyuan*;Sommer, Sven G.;Christensen, Knud V.
期刊：
Energy Policy,2011年39(10):6073-6081 ISSN：0301-4215
通讯作者：
Jiang, Xinyuan
作者机构：
[Jiang, Xinyuan] Cent S Univ Forestry & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Christensen, Knud V.; Sommer, Sven G.] Univ So Denmark, Inst Chem Engn Biotechnol & Environm Technol, Fac Engn, DK-5230 Odense M, Denmark.
通讯机构：
[Jiang, Xinyuan] Cent S Univ Forestry & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.
关键词：
China;Sustainable development;Biogas
摘要：
This article presents an overview of the development and future perspectives of the Chinese biogas industry. The development of the industry has the potential to improve the rural environment and produce significant amounts of sustainable energy for China. Barriers to the development are the relatively weak environmental policies, imperfect financial policies and lack of long-term follow-up services. The rapid economic development of China has also seen a development in the scales of biogas plants constructed. Although the technology has been improved, this review has identified problems in the construction and operation of Chinese biogas plants, particularly in the efficiency of household systems. All levels of China's government acknowledge this and recent biogas projects have more focus on quality and less on the quantity. The intention is to gradually introduce stricter environmental policies, to provide better service systems, improve the financial policies that support the construction and follow-up service of biogas projects, promote the use of standardized engineering equipment and materials and standards for plant construction and production. This will promote the development of biogas projects at various scales further, and reduce the dependency on fossil fuels and emissions of greenhouse gases. (C) 2011 Elsevier Ltd. All rights reserved.
摘要：
Understanding the dynamics and underlying mechanism of carbon exchange between terrestrial ecosystems and the atmosphere is one of the key issues in global change research. In this study, we quantified the carbon fluxes in different terrestrial ecosystems in China, and analyzed their spatial variation and environmental drivers based on the long‐term observation data of ChinaFLUX sites and the published data from other flux sites in China. The results indicate that gross ecosystem productivity (GEP), ecosystem respiration (ER), and net ecosystem productivity (NEP) of terrestrial ecosystems in China showed a significantly latitudinal pattern, declining linearly with the increase of latitude. However, GEP, ER, and NEP did not present a clear longitudinal pattern. The carbon sink functional areas of terrestrial ecosystems in China were mainly located in the subtropical and temperate forests, coastal wetlands in eastern China, the temperate meadow steppe in the northeast China, and the alpine meadow in eastern edge of Qinghai‐Tibetan Plateau. The forest ecosystems had stronger carbon sink than grassland ecosystems. The spatial patterns of GEP and ER in China were mainly determined by mean annual precipitation (MAP) and mean annual temperature (MAT), whereas the spatial variation in NEP was largely explained by MAT. The combined effects of MAT and MAP explained 79%, 62%, and 66% of the spatial variations in GEP, ER, and NEP, respectively. The GEP, ER, and NEP in different ecosystems in China exhibited ‘positive coupling correlation’ in their spatial patterns. Both ER and NEP were significantly correlated with GEP, with 68% of the per‐unit GEP contributed to ER and 29% to NEP. MAT and MAP affected the spatial patterns of ER and NEP mainly by their direct effects on the spatial pattern of GEP.
摘要：
Sources of methane (CH4) become highly variable for countries undergoing a heightened period of development due to both human activity and climate change. An urgent need therefore exists to budget key sources of CH4, such as wetlands (rice paddies and natural wetlands) and lakes (including reservoirs and ponds), which are sensitive to these changes. For this study, references in relation to CH4 emissions from rice paddies, natural wetlands, and lakes in China were first reviewed and then reestimated based on the review itself. Total emissions from the three CH4 sources were 11.25 Tg CH4 yr−1 (ranging from 7.98 to 15.16 Tg CH4 yr−1). Among the emissions, 8.11 Tg CH4 yr−1 (ranging from 5.20 to 11.36 Tg CH4 yr−1) derived from rice paddies, 2.69 Tg CH4 yr−1 (ranging from 2.46 to 3.20 Tg CH4 yr−1) from natural wetlands, and 0.46 Tg CH4 yr−1 (ranging from 0.33 to 0.59 Tg CH4 yr−1) from lakes (including reservoirs and ponds). Plentiful water and warm conditions, as well as its large rice paddy area make rice paddies in southeastern China the greatest overall source of CH4, accounting for approximately 55% of total paddy emissions. Natural wetland estimates were slightly higher than the other estimates owing to the higher CH4 emissions recorded within Qinghai‐Tibetan Plateau peatlands. Total CH4 emissions from lakes were estimated for the first time by this study, with three quarters from the littoral zone and one quarter from lake surfaces. Rice paddies, natural wetlands, and lakes are not constant sources of CH4, but decreasing ones influenced by anthropogenic activity and climate change. A new progress‐based model used in conjunction with more observations through model‐data fusion approach could help obtain better estimates and insights with regard to CH4 emissions deriving from wetlands and lakes in China.
摘要：
Synthesizing biochar-based nano-composites can obtain new composites and combine the advantages of biochar with nano-materials. The resulting composites usually exhibit great improvement in functional groups, pore properties, surface active sites, catalytic degradation ability and easy to separation. These composites have excellent abilities to adsorb a range of contaminants from aqueous solutions. Particularly, catalytic material-coated biochar can exert simultaneous adsorption and catalytic degradation function for organic contaminants removal. Synthesizing biochar-based nano-composites has become an important practice for expanding the environmental applications of biochar and nanotechnology. This paper aims to review and summarize the various synthesis techniques for biochar-based nano-composites and their effects on the decontamination of wastewater. The characteristic and advantages of existing synthesis methods are summarized and discussed. Application of biochar-based nano-composites for different contaminants removal and the underlying mechanisms are reviewed. Furthermore, knowledge gaps that exist in the fabrication and application of biochar-based nano-composites are also identified. (C) 2016 Elsevier Ltd. All rights reserved.
作者机构：
[Wu, Yiqiang; Qing, Yan] Cent South Univ Foreshy & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Sabo, Ronald; Zhu, J. Y.; Cai, Zhiyong; Qing, Yan; Agarwal, Umesh] US Forest Serv, USDA, Forest Prod Lab, Madison, WI 53726 USA.
通讯机构：
[Sabo, Ronald] US Forest Serv, USDA, Forest Prod Lab, Madison, WI 53726 USA.
关键词：
Cellulose nanofibrils;Refining;Microfluidization;Enzymatic and chemical pretreatments
摘要：
Various cellulose nanofibrils (CNFs) created by refining and microfluidization, in combination with enzymatic or 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized pretreatment were compared. The morphological properties, degree of polymerization, and crystallinity for the obtained nanofibrils, as well as physical and mechanical properties of the corresponding films were evaluated. Compared to refining, intense microfluidization contributed greater separation of nanofibril bundles, which led to an enhancement of mechanical strength and transparency for the resultant film. The selected enzymatic pre-treatments produced shortened fibers due to preferential hydrolysis of amorphous cellulose and, in combination with mechanical treatments, resulted in short and stiff cellulose nanocrystal (CNC)-like materials. Despite films from these CNC-like fibrils having inferior tensile strength, their tensile modulus and transparency were significantly improved compared to CNFs prepared without pre-treatment. The unique fiber morphology and high crystallinity potentially offer a green and ecologically friendly alternative for the preparation of CNCs and CNFs as part of an integrated biorefinery approach. Published by Elsevier Ltd.
摘要：
Fibrous bio-nanocomposite mats consisting of cellulose nanocrystals (CNCs) and poly(lactic acid) (PIA) were electrospun from a solvent mixture consisting of N,N'-dimethylformamide and chloroform at room temperature. Morphological, mechanical and thermal properties, as well as in vitro degradation of nanocomposite mats were characterized as a function of material composition. Average diameter of the electrospun fibers decreased with increased CNC-loading level. Thermal stability, and tensile strength and modulus of nanocomposite mats were effectively improved by the addition of CNCs up to the 5 wt% level. The reinforcement of CNCs on electrospun mats was illustrated by the observation of SEM-based morphologies on the tensile fracturing process of nanocomposite mats. At the CNC content of 5 wt%, the maximum tensile stress and Young's modulus of the nanocomposite mats increased by 5 and 22 folds than those of neat PEA mats, respectively. Moreover, compared with neat PEA mats, the nanocomposite mats, especially at high CNC-loading levels, degraded more rapidly in phosphate-buffered saline solution. (C) 2012 Elsevier Ltd. All rights reserved.
摘要：
Evapotranspiration (ET) is a key component of terrestrial ecosystems because it links the hydrological, energy, and carbon cycles. Several satellite-based ET models have been developed for extrapolating local observations to regional and global scales, but recent studies have shown large model uncertainties in ET simulations. In this study, we compared eight ET models, including five empirical and three process-based models, with the objective of providing a reference for choosing and improving methods. The results showed that the eight models explained between 61 and 80% of the variability in ET at 23 eddy covariance towers in China and adjacent regions. The mean annual ET for all of China varied from 535 to 852 mm yr(-1) among the models. The interannual variability of yearly ET varied significantly between models during 1982-2009 because of different model structures and the dominant environmental factors employed. Our evaluation results showed that the parameters of the empirical methods may have different combination because the environmental factors of ET are not independent. Although the three process-based models showed high model performance across the validation Sites, there were substantial differences among them in the temporal and spatial patterns of ET, the dominant environment factors and the energy partitioning schemes. The disagreement among current ET models highlights the need for further improvements and validation, which can be achieved by investigating model structures and examining the ET component estimates and the critical model parameters. (C) 2013 Elsevier Inc. All rights reserved.
摘要：
There is a growing interest of the scientific community on production of activated carbon using biochar as potential sustainable precursors pyrolyzed from biomass wastes. Physical activation and chemical activation are the main methods applied in the activation process. These methods could have significantly beneficial effects on biochar chemical/physical properties, which make it suitable for multiple applications including water pollution treatment, CO2 capture, and energy storage. The feedstock with different compositions, pyrolysis conditions and activation parameters of biochar have significant influences on the properties of resultant activated carbon. Compared with traditional activated carbon, activated biochar appears to be a new potential cost-effective and environmentally-friendly carbon materials with great application prospect in many fields. This review not only summarizes information from the current analysis of activated biochar and their multiple applications for further optimization and understanding, but also offers new directions for development of activated biochar. (C) 2016 Elsevier Ltd. All rights reserved.
关键词：
Soil inorganic carbon;Carbon content;Carbon pool;Agricultural activity;Soil carbon loss
摘要：
The accurate estimation of soil carbon (C) stocks is a necessary component for understanding the global C budget. Although the importance of soil organic C (SOC) within the C cycle is well established, the quantity of soil inorganic C (SIC, including lithogenic and pedogenic inorganic C) pool, another important soil C pool component, has been poorly studied to date. In this study, soil profile data compiled by China's second national soil survey conducted in the 1980s was used to investigate the spatial distribution of SIC for the entire country under present day conditions as well as changes in SIC under historical land use. Results showed that the total SIC storage in China was approximately 55.3 +/- 10.7 Pg C with a current average content of 6.3 +/- 1.2 kg C m(-2), representing 5.8% of the global SIC pool. Land use has significantly affected SIC levels in cultivated soils. Approximately 51% of total cultivated soil surfaces in China have experienced C loss where the most significant loss has been observed in the eastern part of northern China in dry farmlands as well as irrigated soils and paddy soils. On the contrary, SIC has increased (similar to 10%) in irrigated soils in northwestern China. No significant change (similar to 39%) has been observed in soils in southern and the eastern part of northeast China. The total loss of SIC in China was approximately 1.6 Pg C due to extensive human activity. Results of this study indicate that human activity may have had a great impact on SIC as well as SOC pools. (C) 2008 Published by Elsevier B.V.
关键词：
Triticum aestivum;ERF protein TaERF3;TaERF3 overexpression;salt and drought tolerance;stress‐related genes;TaERF3 silencing
摘要：
Salinity and drought are major limiting factors of wheat (Triticum aestivum) productivity worldwide. Here, we report the function of a wheat ERF transcription factor TaERF3 in salt and drought responses and the underlying mechanism of TaERF3 function. Upon treatment with 250 mm NaCl or 20% polyethylene glycol (PEG), transcript levels of TaERF3 were rapidly induced in wheat. Using wheat cultivar Yangmai 12 as the transformation recipient, four TaERF3‐overexpressing transgenic lines were generated and functionally characterized. The seedlings of the TaERF3‐overexpressing transgenic lines exhibited significantly enhanced tolerance to both salt and drought stresses as compared to untransformed wheat. In the leaves of TaERF3‐overexpressing lines, accumulation levels of both proline and chlorophyll were significantly increased, whereas H2O2 content and stomatal conductance were significantly reduced. Conversely, TaERF3‐silencing wheat plants that were generated through virus‐induced gene silencing method displayed more sensitivity to salt and drought stresses compared with the control plants. Real‐time quantitative RT‐PCR analyses showed that transcript levels of ten stress‐related genes were increased in TaERF3‐overexpressing lines, but compromised in TaERF3‐silencing wheat plants. Electrophoretic mobility shift assays showed that the TaERF3 protein could interact with the GCC‐box cis‐element present in the promoters of seven TaERF3‐activated stress‐related genes. These results indicate that TaERF3 positively regulates wheat adaptation responses to salt and drought stresses through the activation of stress‐related genes and that TaERF3 is an attractive engineering target in applied efforts to improve abiotic stress tolerances in wheat and other cereals.
期刊：
Computers and Industrial Engineering,2016年99:287-299 ISSN：0360-8352
通讯作者：
Wang, Jian-qiang
作者机构：
[Wang, Jian-qiang; Zhang, Hong-yu; Wang, Jing] Cent S Univ, Sch Business, Changsha 410083, Hunan, Peoples R China.;[Wang, Jing] Cent South Univ Forestry & Technol, Int Coll, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Wang, Jian-qiang] Cent S Univ, Sch Business, Changsha 410083, Hunan, Peoples R China.
关键词：
Linguistic decision-making;Multi-hesitant fuzzy linguistic term sets (MHFLTSs);Logistics outsourcing;Likelihood;TODIM
摘要：
In this paper, a likelihood-based TODIM approach based on multi-hesitant fuzzy linguistic information is developed for the selection and evaluation of contractors in logistics outsourcing. First, various definitions and operations related to hesitant fuzzy linguistic term sets (HFLTSs) and hesitant fuzzy linguistic sets (HFLSs) are discussed. Next, the definition of multi-hesitant linguistic term sets (MHFLTSs) is reviewed, which can eliminate the limitations associated with HFLTSs and HFLSs as well as emphasize the significance of repeated values. Then, a likelihood function is developed for multi-hesitant fuzzy linguistic term elements (MHFLTEs) based on a generalized function of the possibility degree of real numbers. Using this generalized function based on linguistic scale functions, alternatives that satisfy certain properties can be selected according to various semantic situations and the preferences of decision makers. Finally, the likelihood function of MHFLTEs is embedded into TODIM to address decision-making problems in which decision makers exhibit bounded rationality, and hesitance and repetitiveness exist in the linguistic evaluation information. According to the results of the illustrative examples and comparative analysis, the proposed approach can be used to effectively solve multi-criteria decision making problems involving the selection and evaluation of third-party logistics service providers. (C) 2016 Elsevier Ltd. All rights reserved.
摘要：
Stabilization of heavy metals in situ was investigated. Two combined amendments (LS, limestone+ sepiolite; HZ, hydroxyhistidine+zeolite) were applied at ratios of 0.2%, 0.4%, and 0.8% (w/w) to paddy soil with multi-metal (Pb, Cd, Cu, and Zn) contamination. The effects of these two combined amendments on heavy metal bioavailability in soil, and on uptake and accumulation of heavy metals in rice plants were investigated. Application of LS and HZ significantly increased soil pH values and cation exchange capacity contents, and resulted in a reduction in exchangeable fraction of metals and in extract metal concentrations of amended soils through toxicity characteristic leaching procedure (TCLP). LS and HZ obviously inhibited uptake and accumulation of Pb, Cd, Cu, and Zn in rice plants. Compared with the control soil, concentrations of Pb, Cd, Cu, and Zn in brown rice were decreased by 10.6-31.8%, 16.7-25.5%, 11.5-22.1%, and 11.7-16.3%, respectively, as a result of 0.2% to 0.8% addition of LS, and decreased by 5.1-40.8%, 16.7-20.0%, 8.1-16.2%, and 13.3-21.7%, respectively, as a result of 0.2-0.8% addition of HZ. Significant positive linear correlations were found between heavy metal concentrations in TCLP extracts and those in rice tissues except for Pb. Extracting heavy metals with TCLP was a more suitable method for estimating heavy metal bioavailability concentrations of amended soil than exchangeable fraction of heavy metals, because the latter underestimated heavy metal bioavailability. These results demonstrate that LS and HZ could be effective in reducing heavy metal bioavailability and accumulation in rice grown on multi-metal-contaminated soils. (C) 2014 Elsevier Inc. All rights reserved.
