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论朱熹“变化气质”的思想 被引量:1
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作者 崔涛 李红 《山西高等学校社会科学学报》 2020年第2期74-76,81,共4页
朱熹的"变化气质"就是指通过修身养性使人的后天气质之性恢复到全无不善的先天本然之性;使被后天气质所遮蔽的人心恢复到纯粹清明的义理之心,也即道心。这个过程被朱子诠释为"修为以复其性"。在朱熹的哲学里,"... 朱熹的"变化气质"就是指通过修身养性使人的后天气质之性恢复到全无不善的先天本然之性;使被后天气质所遮蔽的人心恢复到纯粹清明的义理之心,也即道心。这个过程被朱子诠释为"修为以复其性"。在朱熹的哲学里,"变化气质"既是作为修养的最终目标和结果而存在,更是作为修养过程而存在,其本质是一种通过"为学"以实现"为德"的君子修养论,主要途径即"格物""主敬"与"力行"。 展开更多
关键词 朱熹 “变化气质” 本体论 价值论 工夫论
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Tempo-Spatial Variations in Stomatal Conductance, Aperture and Density of Ligustrum sinense Acclimated to Different Light Environments 被引量:5
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作者 张守仁 马克平 陈灵芝 《Acta Botanica Sinica》 CSCD 2002年第10期1225-1232,共8页
There was heterogeneous distribution in stomatal conductance (g-s) and stomatal aperture for both high- and low-light leaves of Ligustrum sinense Lour. in four designated positions within a leaf. Linear or exponential... There was heterogeneous distribution in stomatal conductance (g-s) and stomatal aperture for both high- and low-light leaves of Ligustrum sinense Lour. in four designated positions within a leaf. Linear or exponential or polynomial relationships between g-s and stomatal aperture were found when regression of g-s and stomatal aperture was established. Statistical analysis revealed that the relationship between g-s and stomatal aperture for high-light leaves was more significant than that of low-light leaves. A linear relationship between g-s and stomatal aperture existed in both positions 1 and 3 for both high- and low-light leaves. The stomatal density of the low-light leaves was much lower than that of the high-light leaves. The sensitivity of stomata to changing environment for high-light leaves was higher than that for low-light leaves, which may also relate to the higher stomatal density for the high-light leaves. 展开更多
关键词 ACCLIMATION gas exchange light environment MICROSCOPY stomatal heterogeneity
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Investigation on Steam Gasification of High-metamorphous Anthracite Using Mixed Black Liquor and Calcium Catalyst 被引量:8
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作者 Gul-e-Rana JAFFRI 张济宇 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第4期575-583,共9页
The catalytic effects of single and mixed catalysts, i.e. single 3%Ca and 5%Na-BL(black liquor) catalysts and mixed 3%Ca+5%Na-BL catalyst, on carbon conversion, gasification reaction rate constant and activation en... The catalytic effects of single and mixed catalysts, i.e. single 3%Ca and 5%Na-BL(black liquor) catalysts and mixed 3%Ca+5%Na-BL catalyst, on carbon conversion, gasification reaction rate constant and activation energy, relative amount of harmful pollutant like sulphur containing gases have been investigated by thermogravimetry in steam gasification under temperature 750℃ to 950℃ at ambient pressure for three high-metarnorphous anthracites (Longyan, Fenghai and Youxia coals in Fujian Province). The mixed catalyst of 3%Ca+5%Na-BL increases greatly the carbon conversion and gasification rate constant by accelerating the gasification reaction C+H2O→CO+H2 due to presence of alkali surfacecompounds [COM], [CO2M] and exchanged calcium phenolate and calcium carboxylate (-COO)2. By adding CaCO3 into BL catalyst in gasification, in addition to improving the catalyst function and enhancing the carbon conversion, the effective desulphurization is also achieved, but the better operating temperature should be below 900℃. The homogenous and shrinking core models can be successfully employed to correlate the relations between the conversion and the gasification .time .and to estimate the reaction rate constant, The reaction acUvaUon energy and pre-exponential factor are estimated and the activation energy for mixed catalyst is in a range of 98.72-166.92 kJ·mol^-1, much less than 177.50-196.46 kJ·mol^-1 for non-catalytic steam gasification for three experimental coals. 展开更多
关键词 mixed catalyst CALCIUM black liquor THERMOGRAVIMETRY steam gasification kinetics sulphur containing gas
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Practical Paths towards Lowering Black Carbon Emissions
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作者 Guorui Zhi Xiaoye Zhang Hongbing Cheng Junli Jin Fang Zhang Tingting Wang Xiaochun Zhang 《Advances in Climate Change Research》 SCIE 2011年第1期12-22,共11页
Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduc... Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduction, this paper give1 a brief introduction to the sources and global distribution of BC. Along with the decrease of BC emissions from sue1 actions as the reduction of global greenhouse gases (GHGs) and regulating local air quality, it also highlights othet BC reduction approaches such as control and improvement of combustion conditions, the elimination of open biomas burning, and the sequestration of BC by biomass pyrolysis. Finally, it is stressed that at this moment there is no enougt reason to push BC reduction into any climate change related negotiations, although BC has been included in some o so-called win-win reduction targets for the quick response to both climate and non-climate appeals. 展开更多
关键词 black carbon REDUCTION policy consideration
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Rock chemical weathering by sulfuric acid: pathway, method and prospect
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作者 Dong Zhang Zhiqi Zhao 《Acta Geochimica》 EI CAS CSCD 2017年第3期474-478,共5页
To investigate the role of sulfuric acid-based carbonate weathering in global CO_2 sequestration of climate changes, we systematically discussed the pathway of sulfuric acid in rock chemical weathering and its feedbac... To investigate the role of sulfuric acid-based carbonate weathering in global CO_2 sequestration of climate changes, we systematically discussed the pathway of sulfuric acid in rock chemical weathering and its feedback mechanism for global warming. We showed the methods used to determine the accurate amount of sulfate flux,accounting for the sulfuric acid resulted from sulfide oxidation. Finally, we pointed out some prospects for further detailed work on the exact calculation of the sulfate fluxes for the CO_2 net-release. 展开更多
关键词 Chemical weathering Sulfuric acid Global climate change Sulfate isotope
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The Role of Harmattan in the Edaphic Processes in the Extreme-North-Cameroon
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作者 Anselme Wakponou Monique Mainguet Frederic Dumay 《Journal of Environmental Science and Engineering(B)》 2012年第5期699-708,共10页
In the Cameroonian sudano-sahelian and sahelian zone, karal soils i.e., vertisoils and soils with vertic similarities largely spread on tropical black clay in depressions and fiat sectors. Those black cotton soils are... In the Cameroonian sudano-sahelian and sahelian zone, karal soils i.e., vertisoils and soils with vertic similarities largely spread on tropical black clay in depressions and fiat sectors. Those black cotton soils are out of season's sorghum loft, locally called as muskwari. As the staple diet in the Cameroonian dry areas, this crop becomes more and more an alternative to drying or better to climate changes. Till now, those soils are considered to be lacustrine or they are resulting just from weathering, according to pedologic researchs. The purpose of this communication, therefore, is to show the effects of Harmattan on the basis of our field's observations, investigations and superficial deposits' analysis: granulometry and diffractometry in the laboratory. Harmattan is a dry and stable air mass which originates from the saharian anticyclone. Its participation in edaphics process is very relevant. Indeed, dust storms take place throughout the dry season and vertisoil spreads out on various topographic locations bringing about homogeneity of texture and similarity of mineralogic spectrum. Their high kaolinite content, thin granulometric component (fine sand, silt and clay) are indicative of Aeolian loessial dust deposits. It could not be something else in this area of the most southern saharian blow of the great Saharo-Sahelian GWAS (global wind action system) in sub-equatorial latitudes, in line with the venturi formed by Ennedi and Tibesti mountains. 展开更多
关键词 Society-environment-climate interaction Cameroon HARMATTAN LOESS muskwari vertisoils.
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Developing bioenergy to tackle climate change:Bioenergy path and practice of Tianguan group
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作者 ZHANG Xiao-Yang 《Advances in Climate Change Research》 SCIE CSCD 2016年第1期17-25,共9页
Biomass energy would become the most potential renewable energies, for whether wind power or photovoltaic, would be restricted by the nature thus cannot provide stable power, while biomass energy is the only renewable... Biomass energy would become the most potential renewable energies, for whether wind power or photovoltaic, would be restricted by the nature thus cannot provide stable power, while biomass energy is the only renewable energy that can be used in the form of gas, liquid or solid stage, it could replace the fossil energy, lead a positive influence on the control of the greenhouse gases. Across the globe, the biomass produced through photosynthesis is about 200 Gt, or 99 Gtce per year. If 10% of the biomass is utilized, more than 4 Gt of fuel ethanol and other bioenergy products can be produced, equivalent to 4.13 Gt of petroleum consumed by the world in 2014. Therefore, bioenergy can be a feasible alternative to fossil energy. 展开更多
关键词 Climate change BIOENERGY Greenhouse gas
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Coal matrix deformation characteristics in the process of carbon dioxide displacing different gas saturation coal-bed methane 被引量:1
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作者 Xiao-Ming NI Quan-Zhong LI +1 位作者 Yan-Bin WANG Sha-Sha GAO 《Journal of Coal Science & Engineering(China)》 2013年第3期303-308,共6页
It is fundamental that changes in coal reservoir permeability are researched, in particular, the accurate determination of variations in the coal matrix caused by CO2 replacing CH4 at different gas saturation conditio... It is fundamental that changes in coal reservoir permeability are researched, in particular, the accurate determination of variations in the coal matrix caused by CO2 replacing CH4 at different gas saturation conditions. Based on the surface free energy, the extended Langmuir isothermal adsorption model, combined with CO2 replacing CH4 in experimental trials, and calling on the more general principles and characteristics of the field, mathematical models describing the coal matrix as it undergoes different processes such as CO2 injection and desorption were established. Combined with laboratory data about CO2 replacement under different methane saturation conditions, a law governing the variations in coal matrix CO2 replacement under different methane gas saturation conditions was obtained. The results showed that: in the injection process, the coal matrix expansion rate caused by CO2 or CH4 was exponentially increased with the CO2 pressure increase, the expansion caused by CO2 was far greater than the expansion caused by CH4 in the desorption process, the coal matrix shrinkage caused by CO2 or CH4 was exponentially increased with the pressure decrease, the shrinkage caused by CO2 was larger than the shrinkage caused by CH4 under the same pressure and different gas saturation, the total shrinkage in the desorption process in the coal matrix was greater than the total expansion in the injection process. At higher gas saturations, the total coal matrix shrinkage volume exceeded the total expansion corresponding to pressure points higher in the desorption process. 展开更多
关键词 carbon dioxide coal matrix adsorption swelling desorption contraction
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Effects of Nitrogen-controlled Atmosphere Storage on the Quality of Ordinary Late Japonica Rice
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作者 WANG He SUN Sheng-yuan +3 位作者 LU Yu-jie FU Miao SHEN Xin ZHANG Bao-ming 《Agricultural Science & Technology》 CAS 2022年第4期6-14,共9页
Nitrogen-controlled atmosphere has been internationally recognized as a green grain storage technology.This study used Jiangsu ordinary late japonica rice as the test material and investigated the effects of different... Nitrogen-controlled atmosphere has been internationally recognized as a green grain storage technology.This study used Jiangsu ordinary late japonica rice as the test material and investigated the effects of different nitrogen concentrations(88%,93%,and 98%)and different storage temperatures(10,20,and 30℃)on the rice quality indexes during nitrogen-controlled atmosphere storage.The results showed that the water content of rice in different nitrogen-controlled atmosphere groups fluctuated between 12.85%~13.15%at 20℃,which was significantly lower than that in the control group.High-concentration nitrogen-controlled atmosphere treatment(93%and 98%)effectively slowed down the fatty acid value,malondialdehyde(MDA)content,and electrical conductivity of rice,and also significantly inhibited the rapid increase in the final viscosity and water absorption of rice starch,while the changes in the peak viscosity and attenuation value of rice were not significantly different from those of the control group.Meanwhile,the impacts of controlled atmosphere storage with 98%nitrogen concentration on the water content,fatty acid value,MDA content,electrical conductivity,gelatinization characteristics,and water absorption of rice at 10,20,and 30℃were studied.It was found that all quality parameters,except the MDA content,changed most gently at 10℃.In conclusion,the combined treatment of nitrogen-controlled atmosphere storage(98%)and low temperature(10℃)can effectively delay the quality deterioration of ordinary late japonica rice. 展开更多
关键词 RICE Nitrogen-controlled atmosphere Storage temperature Quality change Gelatinization property
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Variation of cavity gas pressure in slopes with weak intercalation under seismic load
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作者 WANG Xiao-qun CHEN Zhen-lin +1 位作者 ZHOU Zhou SHEN Man 《Journal of Mountain Science》 SCIE CSCD 2016年第2期352-360,共9页
This study discussed how cavity gas pressure affects the stability of rock mass with fractures under well controlled laboratory experiments.Suddenly-created void space created and the induced gas pressures have been t... This study discussed how cavity gas pressure affects the stability of rock mass with fractures under well controlled laboratory experiments.Suddenly-created void space created and the induced gas pressures have been the focus of active researches because they are associated with fast movement of large-scale landslides.A shaking table experiment was set up to mimic weak-intercalated rock slope under seismic loads.Excessive cavity gas pressure would be produced in weak spots upon a sudden vibration load.The drastically elevated gas pressure is believed to be responsible for the creation of cavities surrounding the tension fracture.With dissipation of the excessive cavity gas pressure,the fractures are in unbounded closed-state.This observation explains that the slope body would be split and loosened under several aftershocks,and with the expanding of the cracks,the slope failure eventually occurred.The research of the mechanism of cavity gas pressure could provide a novel insight into the formation mechanism of landslides under seismic load and has implications for the disaster prevention and control theory for the slope stability evaluation. 展开更多
关键词 LANDSLIDE FRACTURE Deformation Weak intercalation Cavity gas pressure
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Process of Salinisation of a Lagoon and a Coastal Aquifer in Annaba Area (East Algerian)
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作者 Mekkakia Mokhtaria Larbi Djabri +4 位作者 Chemseddine Fehdi Fethi Baali Azzedine Hani Antonio Pulido Bosch Saad Bouhsina 《Journal of Agricultural Science and Technology(A)》 2013年第12期973-981,共9页
The study area is located in a Mediterranean region, so the effects of the climate variations are very important. The authors contribution to this subject is based on the compilation of many results obtained from diss... The study area is located in a Mediterranean region, so the effects of the climate variations are very important. The authors contribution to this subject is based on the compilation of many results obtained from dissertations and theses that are carried out under their supervision. The main tool used, in addition to other methods, is the water hydrochemistry as it is proved very useful in obtaining good results and helpful in getting objective interpretations regarding the presence and absence of salinity. Several factors are undertaken to show the presence of salts in waters in the plain, the lithology of the geological formations shows that they are composed of alluvium sediments where the permeability is quite high, and this enables hydraulic communication between the fresh water of the aquifer and saline water of the sea. The study of climate shows a decrease of precipitation which favors an important decrease of recharge rate to the aquifer, and hence a decrease of water resource. The strontium which is a good indicator for the origin of salinity shows a variation that indicates a variation in the distribution of the salinity, and therefore diverse origins of salinity all over the studied area. This can infer the presence of marine invasion in the down-stream part of the aquifer, whereas elsewhere salinity is caused by the presence of evaporitic formation, mainly by the argillaceous matrix in the bottom of the lake. in the up-stream part of the aquifer. In the lake, salinity is explained 展开更多
关键词 LAKE river sea marine invasion AQUIFER TRANSMISSIVITY evaporitic.
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Multivariate Analysis in the Climate Change Studies and Water Quality of Lake Patzcuaro (Mexico)
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《Journal of Mathematics and System Science》 2012年第8期469-481,共13页
In this study, the authors carried out the systemic analysis of water quality of Lake Patzcuaro in relationship with the climate change during a period of 85 years. The statistical comparison (medians, "t" Student ... In this study, the authors carried out the systemic analysis of water quality of Lake Patzcuaro in relationship with the climate change during a period of 85 years. The statistical comparison (medians, "t" Student test, regressions and correlations) for the precipitation, evaporation, observed temperature, minimum and maximum for the periods 1969-1988 (pre-impact) and 1988-2007 (post-impact) was realized. The "t" Student test for water quality during the period of 1981-2011, as well as, the regression analysis and multiple linear correlation of water quality from 2006 to 2011 were applied in joint way of the Cluster and Principal Component to observe the effects of climate change on water quality and vulnerability of Lake Patzcuaro. The comparative analysis of the meteorological data for 1921-1960 and 1973-2007 by the KOppen classification showed a climate change. The comparative Box Plots diagrams for 1973-1989 and 1989-2007, as well as, the "t" Student test, linear regression and correlation indicated significant changes in time for precipitation, evaporation, observed temperature, minimum and maximum (P ≤ 0.05). The correlation and regression analysis indicated significant positive trends for turbidity, conductivity, total phosphorus, aluminum, oils and grease, in contrast with Secchi disk depth, transparency, Redox potential and dissolved oxygen concentration. The "t" Student test showed significant differences between 1981 and 2011 for transparency, hardness, alkalinity, conductivity, nitrite, and phosphate. Cluster and Principal Components of the physicochemical and biological of 2006-2011 confirmed the vulnerability of the system by human growth and climate change influence. 展开更多
关键词 Climatic change LIMNOLOGY statistical analysis.
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Survey on Gamasyab River Water Quality in Nahavand Township, Iran
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作者 M. Reyahi Khoram M. Nafea 《Journal of Agricultural Science and Technology》 2011年第4期495-501,共7页
Gamasyab River, which is the biggest river of Hamadan Province, is sourced from Karstic Springs in Nahavand Township Southern Mountainous Region and supplies a major part of water needs of the region. In this research... Gamasyab River, which is the biggest river of Hamadan Province, is sourced from Karstic Springs in Nahavand Township Southern Mountainous Region and supplies a major part of water needs of the region. In this research seasonal variation of water quality and also the degree of pollution related to Gamasyab River water have been assessed. First the general status of the river was studied and four sampling stations were determined. In this research, the quality of river water including Dissolved Oxygen (DO), five days Biochemical Oxygen Demand (BOD)5, Chemical Oxygen Demand (COD), Nitrate, phosphate, temperature, Total Hardness(TH), Total Suspended Solid (TSS), Total Dissolved Solid (TDS) and PH have been determined and assessed on a monthly basis within a five years period. The results were reported as seasonally and presented using statistical tables and graphs. These results showed that Nitrate concentration in Gamasyab River is strongly depending on distance from Gamasyab spring. By increasing the distance from Gamasyab spring, nitrate concentration increased. The amount of DO in the river water is stable in each station within the year. Air temperature changes have had no effect in the amount of DO. Therefore, it is recommended that the river pollution control plans be implemented more serious than before, non point source pollution related to agricultural activities be managed and prevent from pouring untreated rural wastewaters to the mentioned river. 展开更多
关键词 Environment Gamasyab river water pollution water quality.
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Potential Impacts and Challenges of Climate Change on Water Quality and Ecosystem:Case Studies in Representative Rivers in China 被引量:8
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作者 夏军 程书波 +2 位作者 郝秀平 夏瑞 刘晓洁 《Journal of Resources and Ecology》 CSCD 2010年第1期31-35,共5页
气候变化对水质与水生态的潜在影响已经成为当前必须面对的新问题和新挑战,这也引起了世界各国科学家和政府的高度关注。但是,由于它的复杂性和不确定性,目前针对该问题的科学研究和科学实践仍然十分有限。本文首先回顾了近年来国内外... 气候变化对水质与水生态的潜在影响已经成为当前必须面对的新问题和新挑战,这也引起了世界各国科学家和政府的高度关注。但是,由于它的复杂性和不确定性,目前针对该问题的科学研究和科学实践仍然十分有限。本文首先回顾了近年来国内外相关研究成果,并指出了研究现状与现实需要之间的差距。另外,基于作者在淮河和汉江的相关研究成果,我们认为,人类活动和经济发展所产生的排污是造成水质与水生态恶化的最重要的原因,同时,气候变化在此基础上具有推波助澜的增益作用,气候变化主要通过改变水温和水文情势进而影响水质和水生态。本文最后讨论了适应性对策的内涵,认为适应性对策应该包括适应方式和适应能力建设两个主要方面,适应性对策应该尽可能地具有针对性和可操作性。本文对今后的相关研究可起澄清概念和指明方向的作用。 展开更多
关键词 potential impact CHALLENGE climate change water quality and ecosystem
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Homogenization of climate series:The basis for assessing climate changes 被引量:14
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作者 YAN ZhongWei LI Zhen XIA JiangJiang 《Science China Earth Sciences》 SCIE EI CAS 2014年第12期2891-2900,共10页
Long-term meteorological observation series are fundamental for reflecting climate changes.However,almost all meteorological stations inevitably undergo relocation or changes in observation instruments,rules,and metho... Long-term meteorological observation series are fundamental for reflecting climate changes.However,almost all meteorological stations inevitably undergo relocation or changes in observation instruments,rules,and methods,which can result in systematic biases in the observation series for corresponding periods.Homogenization is a technique for adjusting these biases in order to assess the true trends in the time series.In recent years,homogenization has shifted its focus from the adjustments to climate mean status to the adjustments to information about climate extremes or extreme weather.Using case analyses of ideal and actual climate series,here we demonstrate the basic idea of homogenization,introduce new understanding obtained from recent studies of homogenization of climate series in China,and raise issues for further studies in this field,especially with regards to climate extremes,uncertainty of the statistical adjustments,and biased physical relationships among different climate variables due to adjustments in single variable series. 展开更多
关键词 climate series INHOMOGENEITY HOMOGENIZATION trends in climate series climate extremes
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Carbon and Nitrogen Storage in Inner Mongolian Grasslands: Relationships with Climate and Soil Texture 被引量:8
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作者 HE Nian-Peng WANG Ruo-Meng +1 位作者 ZHANG Yun-Hai CHEN Quan-Sheng 《Pedosphere》 SCIE CAS CSCD 2014年第3期391-398,共8页
Understanding the spatial variability of soil carbon (C) storage and its relationship with climate and soil texture is critical for developing regional C models and for predicting the potential impact of climate cha... Understanding the spatial variability of soil carbon (C) storage and its relationship with climate and soil texture is critical for developing regional C models and for predicting the potential impact of climate change on soil C storage. On the basis of soil data from a transect across the Inner Mongolian grasslands, we determined the quantitative relationships of C and nitrogen (N) in bulk soil and particle-size fractions (sand, silt, and clay) with climate and soil texture to evaluate the major factors controlling soil C and N storage and to predict the effect of climate changes on soil C and N storage. The contents of C and N in the bulk soil and the different fractions in the 0 20 and 20 40 cm soil layers were positively correlated with the mean annum precipitation (MAP) and negatively correlated with the mean annual temperature (MAT). The responses of C storage in the soil and particle-size fractions to MAP and MAT were more sensitive in the 0-20 cm than in the 2(~40 cm soil layer. Although MAP and MAT were both important factors influencing soil C storage, the models that include only MAP could well explain the variation in soil C storage in the Inner Mongolian grasslands. Because of the high correlation between MAP and MAT in the region, the models including MAT did not significantly enhance the model precision. Moreover, the contribution of the fine fraction (silt and clay) to the variation in soil C storage was rather small because of the very low fine fraction content in the Inner Mongolian grasslands. 展开更多
关键词 mean annual precipitation mean annual temperature native grassland particle-size fraction soil organic matter
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Regional Diferences in the Efect of Climate and Soil Texture on Soil Organic Carbon 被引量:1
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作者 WANG Mei-Yan SHI Xue-Zheng +4 位作者 YU Dong-Sheng XU Sheng-Xiang TAN Man-Zhi SUN Wei-Xia ZHAO Yong-Cun 《Pedosphere》 SCIE CAS CSCD 2013年第6期799-807,共9页
The agricultural soil carbon pool plays an important role in mitigating greenhouse gas emission ana unaerstanamg the son orgamc carbon-climate-soil texture relationship is of great significance for estimating cropland... The agricultural soil carbon pool plays an important role in mitigating greenhouse gas emission ana unaerstanamg the son orgamc carbon-climate-soil texture relationship is of great significance for estimating cropland soil carbon pool responses to climate change. Using data from 900 soil profiles, obtained from the Second National Soil Survey of China, we investigated the soil organic carbon (SOC) depth distribution in relation to climate and soil texture under various climate regimes of the cold northeast region (NER) and the warmer Huang-Huai-Hai region (HHHR) of China. The results demonstrated that the SOC content was higher in NER than in HHHR. For both regions, the SOC content at all soil depths had significant negative relationships with mean annual temperature (MAT), but was related to mean annual precipitation (MAP) just at the surface 0-20 cm. The climate effect on SOC content was more pronounced in NER than in HHHR. Regional differences in the effect of soil texture on SOC content were not found. However, the dominant texture factors were different. The effect of sand content on SOC was more pronounced than that of clay content in NER. Conversely, the effect of clay on SOC was more pronounced than sand in HHHR. Climate and soil texture jointly explained the greatest SOC variability of 49.0% (0-20 cm) and 33.5% (20-30 cm) in NER and HHHR, respectively. Moreover, regional differences occurred in the importance of climate vs. soil texture in explaining SOC variability. In NER, the SOC content of the shallow layers (0-30 cm) was mainly determined by climate factor, specifically MAT, but the SOC content of the deeper soil layers (30-100 cm) was more affected by texture factor, specifically sand content. In HHHR, all the SOC variability in all soil layers was predominantly best explained by clay content. Therefore, when temperature was colder, the climate effect became stronger and this trend was restricted by soil depth. The regional differences and soil depth influence underscored the importance of explicitly considering them in modeling long-term soil responses to climate change and predicting potential soil carbon sequestration. 展开更多
关键词 climate change CROPLAND soil carbon pool soil depth TEMPERATURE
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Loess in China: A Good Archive of Climatic and Environmental Changes during the Quaternary
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作者 Wang Limeng Lu Huayu 《Science Foundation in China》 CAS 2005年第1期41-44,共4页
Quaternary scientists in China have significantly improved our knowledge of loess deposition as well as our understanding of paleoclimatic and paleoen- vironmental changes over the past 2.5 million years. It is recogn... Quaternary scientists in China have significantly improved our knowledge of loess deposition as well as our understanding of paleoclimatic and paleoen- vironmental changes over the past 2.5 million years. It is recognized that loess is of aeolian origin with loess forming dust continuously deposited. It is also believed that grain-size, magnetic suscepti- bility, carbon isotopes and fossil assemblages in loess deposits are good proxy indicators of pale- omonsoon climate and paleovegetation changes over the past 2. 5 million years. Chinese loess is regard- ed as one of the best terrestrial archives of climatic and environmental changes during the Quaternary. Further investigation of loess deposits and their records of climatic and environmental change aids understanding of climate change and gives scientific backing for the project of ecological and environ- mental restoration in northwest China . 展开更多
关键词 Chinese loess the Quaternary paleoclimatic archives
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Forecasting the impacts of chemical pollution and climate change interactions on the health of wildlife 被引量:1
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作者 Pamela D. NOYES Sean C. LEMA 《Current Zoology》 SCIE CAS CSCD 2015年第4期669-689,共21页
Global climate change is impacting organisms, biological communities and ecosystems around the world. While most research has focused on characterizing how the climate is changing, including modeling future climatic c... Global climate change is impacting organisms, biological communities and ecosystems around the world. While most research has focused on characterizing how the climate is changing, including modeling future climatic conditions and predicting the impacts of these conditions on biodiversity, it is also the case that climate change is altering the environmental impacts of chemical pollution. Future climate conditions are expected to influence both the worldwide distribution of chemicals and the toxi- cological consequences of chemical exposures to organisms. Many of the environmental changes associated with a warming global climate (e.g., increased average - and possibly extreme - temperatures; intense periods of drier and wetter conditions; reduced ocean pH; altered salinity dynamics in estuaries) have the potential to enhance organism susceptibility to chemical toxicity. Addi- tionally, chemical exposures themselves may impair the ability of organisms to cope with the changing environmental conditions of the shifting climate. Such reciprocity in the interactions between climate change and chemicals illustrates the complexity inherent in predicting the toxicological consequences of chemical exposures under future climate scenarios. Here, we summarize what is currently known about the potential reciprocal effects of climate change and chemical toxicity on wildlife, and depict current approaches and ongoing challenges for incorporating climate effects into chemical testing and assessment. Given the rapid pace of new man-made chemistries, the development of accurate and rapid methods to evaluate multiple chemical and non-chemical stressors in an ecologically relevant context will be critical to understanding toxic and endocrine-disrupting effects of chemical pollutants under future climate scenarios [Current Zoology 61 (4): 669-689, 2015]. 展开更多
关键词 Global wanning TOXICOLOGY METALS Endocrine disruptors Risk assessment
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