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森林生态系统吸碳量高于预期量
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作者 闫静 《世界环境》 1996年第1期33-34,共2页
森林生态系统吸碳量高于预期量CarbonSequestrationinForestEcosystemsHigherthanExpected¥J.A.VerweijAbstract:Inthecarboncycle,f... 森林生态系统吸碳量高于预期量CarbonSequestrationinForestEcosystemsHigherthanExpected¥J.A.VerweijAbstract:Inthecarboncycle,forestsfunctionasa... 展开更多
关键词 森林生态系统 吸碳量 预期 二氧化
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岩溶系统对大气 CO_2 的调节作用 被引量:1
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作者 杨立铮 卫迦 《成都理工大学学报(自然科学版)》 CAS CSCD 1997年第S1期32-39,共8页
本文通过对中国南方岩溶区近2000个水化学分析资料的统计分析,研究了云南、贵州、四川、广西、湖南、湖北六省(区)岩溶水CO2含量,CO2吸收模数,计算了南方碳酸盐岩出露区和分布区岩溶系统吸收CO2的数量,对全国碳酸盐... 本文通过对中国南方岩溶区近2000个水化学分析资料的统计分析,研究了云南、贵州、四川、广西、湖南、湖北六省(区)岩溶水CO2含量,CO2吸收模数,计算了南方碳酸盐岩出露区和分布区岩溶系统吸收CO2的数量,对全国碳酸盐岩出露区吸收的CO2作了估算,90.7万km2的碳酸盐岩出露面积所吸收的CO2为14.03×109kg/a,在碳循环平衡计算中,除了海洋吸收,大气增量以外,还有12%被“遗漏的汇”吸收,岩溶系统吸收的CO2在这12%中占15%,它是全球碳循环的一个重要组成部分,是一个被“遗漏的汇”,它对大气CO2具有不可忽视的调节功能。 展开更多
关键词 岩溶系统 循环 CO2收模数 吸碳量 温室效应
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Effects of Different Fertilization Treatments on Biological Activity of Reclaimed Soil
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作者 张平 洪坚平 +1 位作者 乔志伟 李娜 《Agricultural Science & Technology》 CAS 2016年第3期619-623,共5页
As per randomized block design, the research had different fertilizer treatments, and the organic matter, respiration, enzyme activity and microbial carbon and nitrogen in reclaimed soil were studied. Fertilization sc... As per randomized block design, the research had different fertilizer treatments, and the organic matter, respiration, enzyme activity and microbial carbon and nitrogen in reclaimed soil were studied. Fertilization schemes were as follows: The treatment without fertilizers(CK), the treatment with chemical fertilizers(C), the treatment with chemical fertilizers and bacterial fertilizer(CB), the treatment with organic fertilizer and chemical fertilizers(CM), and the treatment with chemical fertilizers, organic fertilizer and bacterial fertilizer(CMB). The results showed: Four fertilization treatments could improve the content of soil organic matter. CMB, CM and CB could significantly improve the soil respiration. Organic fertilizer and fertilizer could significantly improve soil enzyme activity, In different growth stages the CMB treatment had highest urease and phosphatase.The most significant in the treatment content of sucrose was CM. Organic fertilizer and microbial fertilizer can significantly improve the microbial carbon and nitrogen in soil. For the microbial biomass carbon, the CMB treatment increased by 11%-34% than CB treatment, and 35%-63% than C treatment. In terms of microbial nitrogen CMB, CM respectively increased by 31%-51% than CB treatment, and 52%-100% compared with C. In the process of land reclamation, we should combine the organic fertilizer, microbial fertilizer and inorganic fertilizer. Only in this way can soil biological activity be accelerated, soil microbial environment improved, and the ripening increased soil nutrient and soil cultivation be enhanced. 展开更多
关键词 Different fertilization treatments Soil rehabilitation Enzyme activity Soil respiration Microbial biomass carbon and nitrogen
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Influence of Carbon Content on S Zorb Sorbent Activity 被引量:4
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作者 Xu Li 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第2期6-10,共5页
The reaction activity of S Zorb sorbents with different sulfur contents was investigated, and the structure and composition of carbon-containing sorbents were characterized by XRD, FT-IR and TG-MS in order to delve in... The reaction activity of S Zorb sorbents with different sulfur contents was investigated, and the structure and composition of carbon-containing sorbents were characterized by XRD, FT-IR and TG-MS in order to delve into the kind and morphology of carbon on the sorbent. Test results have revealed that coke could be deposited on the S Zorb sorbent during the operating process, and the coke content was an important factor influencing the reaction performance of the S Zorb sorbent. Retention of a definite amount of coke on the sorbent while securing the desulfurization activity of the S Zorb sorbent would be conducive to the reduction of octane loss of reaction product. 展开更多
关键词 S Zorb sorbent carbon content desulfurization activity octane loss
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Microbial Development in Soils Under Intensively Managed Bamboo (Phyllostachys praecox) Stands 被引量:3
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作者 XUQiu-Fang JIANGPei-Kun 《Pedosphere》 SCIE CAS CSCD 2005年第1期33-40,共8页
Phyllostachys praecox C. D. Chu et C. S. Chao, a favored bamboo shoot species, has been widely planted in recent years. Four stands with different historical management practices were selected for this study to unders... Phyllostachys praecox C. D. Chu et C. S. Chao, a favored bamboo shoot species, has been widely planted in recent years. Four stands with different historical management practices were selected for this study to understand the evolution of soil microbial ecology by determining the effects of a new mulching and heavy fertilization practice on soil quality using microbiological parameters. Compared with the traditional practice (index 1), microbial biomass carbon (MBC) and soil microbial respiration carbon (MRC) with the new management practice significantly decreased (P < 0.01 and P < 0.05,respectively) with 1-2 years of mulching (index 2) and then for continued mulching significantly increased (P < 0.05). The ratios of MBC/TOC (total organic carbon) and MRC/TOC also significantly diminished (P < 0.05) with mulching. The average well color development (AWCD) and Shannon index decreased with mulching time, and the significant decrease(P < 0.05) in Shannon index occurred from index 2 to index 3. The results from a principal components analysis (PCA)showed that the scores of the first principal component for indexes 1 and 2 were significantly larger (P < 0.05) than soils mulched 3-4 years or 5-6 years. Also, the second principal component scores for index 1 were larger than those for index 2, suggesting that the ability of soil microorganisms to utilize soil carbon was decreasing with longer use of the new management practice and causing a deterioration of soil biological properties. 展开更多
关键词 microbial biomass carbon microbial functional diversity microbial respiration carbon Phyllostachys praecox SOIL
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Carbon Budget of Bastard Halibut Paralichthys Olivaceus in Relation to Body Weight and Temperature 被引量:7
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作者 线薇薇 刘瑞玉 朱鑫华 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第2期134-140,共7页
The effects of body weight and temperature on the carbon budget of the juvenile bastard halibut,Paralichthys olivaceus, were studied at temperature 13.5, 18, 21.5 and 24 ℃, respectively. The carbon intake, faecal and... The effects of body weight and temperature on the carbon budget of the juvenile bastard halibut,Paralichthys olivaceus, were studied at temperature 13.5, 18, 21.5 and 24 ℃, respectively. The carbon intake, faecal and growth carbon were measured, and the carbon respiration was calculated using the carbon budget equation (C C=G C+F C+R C). The combined relationship between different components of the carbon budget, body weight and temperature could be described by regression equations:C C=1.0206W 0.8126e 0.1483T; G C=0.0042W 1.4096 (-5.11T3+285.90T2-5173.72T+30314.03);F C=0.0485W 0.7711e 0.1624T U C = 1.4333W 0.6715e 0.1487T. Body weight had no significant effect on the carbon absorption efficiency and the conversion efficiency. 展开更多
关键词 carbon budget body weight TEMPERATURE Paralichthys olivaceus
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Carbonaceous Adsorbents Prepared from Sewage Sludge and Its Application for Hg^0 Adsorption in Simulated Flue Gas 被引量:11
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作者 方平 岑超平 +1 位作者 陈定盛 唐志雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期231-238,共8页
The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Four... The carbonaceous adsorbent was prepared from mixtures of dewatered sludge and sawdust with enhanced ZnCl2 chemical activation.Characteristics of the adsorbent were studied using scanning electron microscope(SEM) ,Fourier transform infrared spectroscopy(FT-IR) ,and adsorption of nitrogen.The surface analysis showed that the carbonaceous adsorbent had good specific surface and porosity(394 m 2 ·g-1of BET surface,0.12 and 0.10 ml·g-1of microporous and mesoporous volume,respectively) .The oxygen functional groups such as OH,C O and C O were found on the surface by FTIR and XPS(X-ray photoelectron spectroscopy) .The adsorption of elemental mercury(Hg0) on the carbonaceous adsorbent was studied in a fixed bed reactor.The dynamic adsorption capacity of carbonaceous adsorbent increased with influent mercury concentration,from 23.6μg·g-1at 12.58μg·m-3to 87.9μg·g-1at 72.50μg·m-3,and decreased as the adsorption temperature increased,from 246 μg·g-1 at 25°C to 61.3μg·g-1 at 140°C,when dry nitrogen was used as the carrier gas.The carbonaceous adsorbent presented higher dynamic adsorption capacity than activated carbon,which was 81.2μg·g-1and 53.8μg·g-1respectively.The adsorption data were fitted to the Langmuir adsorption model.The physical and chemical adsorption were identified on the adsorbent. 展开更多
关键词 carbonaceous adsorbent dewatered sludge Hg0
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Sorption and Diffusion Behavior of Carbon Dioxide into Poly(l-lactic acid) Films at Elevated Pressures 被引量:1
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作者 余金鹏 唐川 +2 位作者 关怡新 姚善泾 朱自强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第11期1296-1302,共7页
Equilibrium sorption amount, desorption diffusion coefficients and sorption diffusion coefficients of CO2 in poly(l-lactic acid) (PLLA) films at elevated pressures were determined by the gravimetric method, in whi... Equilibrium sorption amount, desorption diffusion coefficients and sorption diffusion coefficients of CO2 in poly(l-lactic acid) (PLLA) films at elevated pressures were determined by the gravimetric method, in which the Fick's diffusion model was applied to analyze both the desorption and sorption processes. The equilibrium sorption amount of CO2 in PLLA increased with lowering temperature and elevating pressure at the temperature range from 40 to 60 ℃ and pressure from 10^4 to 2x10^4 kPa. Desorption diffusion coefficients were greatly influenced by the equilibrium sorption amount, and they were in the same order of magnitude as the sorption diffusion coefficients. The scan electron microscope (SEM) photos demonstrated that there was no foaming phenomenon of the PLLA film during desorption and sorption processes. The XRD spectra implied that the crystalline degree of PLLA film decreased after CO2 processing. It was concluded that PLLA polymer could be well swollen and plasticized by supercritical CO2. 展开更多
关键词 supercritical solution impregnation carbon dioxide poly (/-lactic acid) SORPTION DIFFUSION
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Adsorption of Cholesterol on Carbon Powders
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作者 Jennifer Lee Gordon Thomas Roy Rybolt Christina Elizabeth Wells 《Journal of Chemistry and Chemical Engineering》 2010年第9期14-27,共14页
Carbon powders have the ability to remove cholesterol from solution by adsorption. Various combinations from among 12 different types of carbon powders (including two medical carbons), having a wide range of surface... Carbon powders have the ability to remove cholesterol from solution by adsorption. Various combinations from among 12 different types of carbon powders (including two medical carbons), having a wide range of surface area and porosity, were used to perform cholesterol adsorption experiments. The cholesterol concentration in a cyclohexane solvent (37 ~C, shaking 200 rpm) was detected at 215 nm using ultraviolet spectroscopy. Most adsorption occurred in the first 30 to 60 minutes. A Langmuir model was used to fit the amount of cholesterol adsorbed per gram of carbon. The medical carbon, Natural Elements Activated Charcoal, adsorbed 234 mg of cholesterol adsorption per gram of carbon. The experimental percentages of cholesterol removed from solution (maximum 98%) were correlated with nitrogen Branauer-Emmett-Teller (BET) surface areas and micro, meso, and macropore volume distributions. Surface area alone was not a suitable predictor of cholesterol adsorption. However, carbon powders exhibiting a large surface area along with significant meso and macropores were shown to be effective in adsorbing cholesterol from a nonpolar environment. Ingestion of a medically approved carbon powder with a large surface area and sufficient meso and macroporosity may be able to adsorb cholesterol in the intestinal tract and thereby lower cholesterol levels in the body. 展开更多
关键词 CHOLESTEROL adsorption capacity adsorption from solution Langmuir isotherm enterosorption POROSITY BET surface area carbon powder.
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Collapse behavior evaluation of hybrid thin-walled member by stacking condition 被引量:2
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作者 Kil-Sung LEE Hyeon-Kyeong SEO +3 位作者 Yong-June YANG Woo-Chae HWANG Kwang-Hee IM In-Young YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第A01期135-140,共6页
The recent trend of vehicle design aims at crash safety and environmentally-friendly aspect. For the crash safety aspect, the energy absorbing members should absorb collision energy sufficiently but for the environmen... The recent trend of vehicle design aims at crash safety and environmentally-friendly aspect. For the crash safety aspect, the energy absorbing members should absorb collision energy sufficiently but for the environmentally-friendly aspect, the vehicle structure must be light weight in order to improve the fuel efficiency and reduce the tail gas emission. Therefore, the light weight of vehicle must be achieved in a securing safety status of crash. An aluminum or carbon fiber reinforced plastics (CFRP) is representative one of the light-weight materials. Based on the respective collapse behavior of aluminum and CFRP member, the collapse behavior of hybrid thin-walled member was evaluated. The hybrid members were manufactured by wrapping CFRP prepreg sheets outside the aluminum hollow members in the autoclave. Because the CFRP is an anisotropic material whose mechanical properties, such as strength and elasticity, change with its stacking condition, the effects of the stacking condition on the collapse behavior evaluation of the hybrid thin-walled member were tested. The collapse mode and energy absorption capability of the hybrid thin-walled member were analyzed with the change of the fiber orientation angle and interface number. 展开更多
关键词 collapse behavior aluminum and CFRP hybrid thin-walled member stacking condition
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Synthesis and evaluation of carbon nanotubes composite adsorbent for CO2 capture: a comparative study of CO2 adsorption capacity of single-walled and multi-walled carbon nanotubes 被引量:2
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作者 Keren Osier Dhruti Dheda +2 位作者 Jacob Ngoy Nicola Wagner Michael O. Daramola 《International Journal of Coal Science & Technology》 EI 2017年第1期41-49,共9页
As a preliminary investigation towards obtaining carbon nanotube composite adsorbent for CO2 capture, in this study CO2 adsorption performance of three commercial carbon nanotubes (CNTs) one single-walled carbon nan... As a preliminary investigation towards obtaining carbon nanotube composite adsorbent for CO2 capture, in this study CO2 adsorption performance of three commercial carbon nanotubes (CNTs) one single-walled carbon nanotubes (SWCNTs), and two (2) different multi-walled carbon nanotubes (referred to as A-MWCNTs and B-MWCNTs) were evaluated and compared. The purpose of this study was to compare the different types of CNTs and select the best to serve as the solid anchor in the development of a hydrophobic composite adsorbent material for CO2 capture. The N2 physi- sorption of the CNTs was conducted to determine their surface area, pore volume and pore size. In addition, morphology and purity of the CNTs were checked with Transmission Electron Microscopy and Raman Spectroscopy, respectively. The CO2 adsorption capacity of the CNTs was evaluated using Thermo-gravimetric analysis (TGA) at 1.1 bar, at operating temperature ranged from 25 to 55 ~C and at different CO2 feed flow rates, in order to evaluate the effects of these variables on the CO2 adsorption capacity. The results of CO2 adsorption with the TGA show that CO2 adsorption capacity for both SWCNTs and MWCNTs was the highest at 25 ~C. Changing the CO2 flowrates had no significant effect on the adsorption capacity of MWCNTs, but decreasing the CO2 flow rate resulted in the enhancement of the CO2 adsorption capacity of SWCNTs. Overall, it was found that the SWCNTs displayed the highest CO2 adsorption capacity (29.97 gCO2/kg ad- sorbent) when compared to the MWCNTs (12.09 gCO2/kg adsorbent), indicating a 150% increase in adsorption capacity over MWCNTs. 展开更多
关键词 CO2 Capture ADSORPTION Carbon nanotubes Single-walled nanotubes Multi-walled nanotubes
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Characterization of Humic System in Fertilizer Raw Materials
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作者 Ekaterina Filcheva Rossitza Ilieva +3 位作者 Kosnstantin Chakalov Todorka Popova Valentin Savov Mariana Hristova 《Journal of Agricultural Science and Technology(A)》 2017年第1期11-17,共7页
The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. (Plantagra), plant materials after pyrolisis (cha... The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. (Plantagra), plant materials after pyrolisis (charcoal) and composts are compared. Humus systems are characterized by Kononova-Belchikova's method, and heavy metals content was measured by atomic absorption spectroscopy (AAS). Humic acids from the International Humic Substances Society (IHSS) collection are the standards for humus substances quality of compared products. Data obtained for leonardite indicate that the studied substances from factory, Izmir, Turkey contain humic acids over 94%. Compared to the standard, heavy metals content in these materials demonstrate high amounts. Organic carbon content in the composts is very low compared to the leonardite materials and IHSS collection, where the heavy metals content is lower. Biotransformed lignite is characterized with lower content of organic carbon, but humic acids are with high degree of humification. Results obtained show that the fourth studied humus systems may be used in agriculture on base of the high humic acids content. It is recommended to measure heavy metals content before applying the materials in agriculture. 展开更多
关键词 COMPOST humic acid leonardite LIGNITE sewage sludge Trichoderma harzianum Trichoderma viride.
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Influence of Artificial Light on Laying Hens Production of Heat, Moisture and Carbon Dioxide in a Floor Housing System
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作者 Gosta Gustafsson Eva Von Wachenfelt 《Journal of Agricultural Science and Technology(A)》 2012年第9期1086-1093,共8页
Investigations about laying hens reactions on artificial light conditions were carried out in a climate chamber equipped with a floor housing system for laying hens. The release of moisture increased during light peri... Investigations about laying hens reactions on artificial light conditions were carried out in a climate chamber equipped with a floor housing system for laying hens. The release of moisture increased during light periods probably due to increased activity which increased respiration rate but also on increased scratching which increased evaporation of moisture from bedding material. The daily average was 6.29 g henl h"l at 4 lux and 5.97 g henl hl, at 93 lux which corresponds to a difference of 5%. The level of light intensity seemed to have little influence on the release of moisture. The total release of heat was slightly higher during light periods compared to dark periods. Explanations can be increased activity but also feed intake increasing the metabolic rate during light periods. The daily average of total heat production was 17.0 W per hen at 4 lux and 14.7 at 93 lux which corresponds to a difference of 16%. The release of carbon dioxide increased during light periods probably due to increased activity and respiration. 展开更多
关键词 Laying hens artificial light HEAT MOISTURE carbon dioxide.
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Relationship Between Vegetation Restoration and Soil Microbial Characteristics in Degraded Karst Regions: A Case Study 被引量:33
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作者 WEI Yuan YU Li-Fei +2 位作者 ZHANG Jin-Chi YU Yuan-Chun D. L. DEANGELIS 《Pedosphere》 SCIE CAS CSCD 2011年第1期132-138,共7页
The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last decade.In an attempt to preferably interpret the soil microbiological characteristic... The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last decade.In an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern Guizhou Province,China.The community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial communities.The results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land stage.Similar trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2) decreased with vegetation restoration,and remained at a constantly low level in the arboreal community stage.Analyses of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional diversity.Average utilization of specific substrate guilds was highest in the arboreal community stage.Principle component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three stages.In conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2,thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions. 展开更多
关键词 basal respiratory community level physiological profile functional diversity metabolic quotient microbial biomass C
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Polymer-coated nanoporous carbons for trace seawater uranium adsorption 被引量:11
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作者 YUE YanFeng SUN XiaoGuang +7 位作者 MAYES Richard T. KIM Jungseung FULVIO Pasquale F. QIAO ZhenAn BROWN Suree TSOURIS Costas OYOLA Yatsandra DAI Sheng 《Science China Chemistry》 SCIE EI CAS 2013年第11期1510-1515,共6页
Polymer-coated mesoporous carbon nanocomposites were prepared from the immobilization of acrylonitrile and acrylic acid copolymers with divinylbenzene as a crosslinker onto a mesoporous carbon framework.High surface a... Polymer-coated mesoporous carbon nanocomposites were prepared from the immobilization of acrylonitrile and acrylic acid copolymers with divinylbenzene as a crosslinker onto a mesoporous carbon framework.High surface areas were maintained after polymerization with accessible porosity.This functional nanocomposite was tested as an adsorbent for uranium from high salinity solutions.Uranium adsorption results have shown that the adsorption capacities are strongly influenced by the density of the amidoxime groups and the specific surface area. 展开更多
关键词 mesoporous carbon NANOCOMPOSITE COPOLYMERIZATION seawater uranium adsorption
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Soil Respiration, Microbial Biomass C and N Availability in a Sandy Soil Amended with Clay and Residue Mixtures 被引量:1
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作者 Sharmistha PAL Petra MARSCHNER 《Pedosphere》 SCIE CAS CSCD 2016年第5期643-651,共9页
Crop yields in sandy soils can be increased by addition of clay-rich soil, but little is known about the effect of clay addition on nutrient availability after addition of plant residues with different C/N ratios. A l... Crop yields in sandy soils can be increased by addition of clay-rich soil, but little is known about the effect of clay addition on nutrient availability after addition of plant residues with different C/N ratios. A loamy sandy soil (7% clay) was amended with a clay-rich subsoil (73% clay) at low to high rates to achieve soil mixtures of 12%, 22%, and 30% clay, as compared to a control (sandy soil alone) with no clay addition. The sandy-clay soil mixtures were amended with finely ground plant residues at 10 g kg-l: mature wheat (Triticum aestivum L.) straw with a C/N ratio of 68, mature faba bean (Vicia faba L.) straw with a C/N ratio of 39, or their mixtures with different proportions (0% 100%, weight percentage) of each straw. Soil respiration was measured over days 0-45 and microbial biomass C (MBC), available N, and pH on days 0, 15, 30, and 45. Cumulative respiration was not clearly related to the C/N ratio of the residues or their mixtures, but C use efficiency (cumulative respiration per unit of MBC on day 15) was greater with faba bean than with wheat and the differences among the residue mixtures were smaller at the highest clay addition rate. The MBC concentration was lowest in sole wheat and higher in residue mixtures with 50% of wheat and faba bean in the mixture or more faba bean. Soil N availability and soil pH were lower for the soil mixtures of 22% and 30% clay compared to the sandy soil alone. It could be concluded that soil cumulative respiration and MBC concentration were mainly influenced by residue addition, whereas available N and pH were influenced by clay addition to the sandy soil studied. 展开更多
关键词 available N C use efficiency C/N ratio cumulative respiration nutrient availability pH plant residues
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Effect of vegetation type, wetting intensity, and nitrogen supply on external carbon stimulated heterotrophic respiration and microbial biomass carbon in forest soils 被引量:6
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作者 WU HaoHao XU XingKai +2 位作者 DUAN CunTao LI TuanSheng CHENG WeiGuo 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第8期1446-1456,共11页
By using packed soil-core incubation experiments, we have studied stimulating effects of addition of external carbon (C) (glu- cose, 6.4 g C m 2) on heterotrophic respiration and microbial biomass C of a mature br... By using packed soil-core incubation experiments, we have studied stimulating effects of addition of external carbon (C) (glu- cose, 6.4 g C m 2) on heterotrophic respiration and microbial biomass C of a mature broadleaf and Korean pine mixed forest (BKPF) and an adjacent white birch forest (WBF) soil under different wetting intensities (55% and 80% WFPS, water-filled pore space) and nitrogen (N) supply (NH4C1 and KNO3, 4.5 g N m-e) conditions. The results showed that for the control, the cumulative carbon dioxide (CO2) flux from WBF soil during the 15-day incubation ranged from 5.44 to 5.82 g CO2-C m-2, which was significantly larger than that from BKPF soil (2.86 to 3.36 g CO2-C m 2). With increasing wetting intensity, the cumulative CO2 flux from the control was decreased for the WBF soil, whereas an increase in the CO2 flux was observed in the BKPF soil (P 〈 0.05). The addition of NH4C1 or KNO3 alone significantly reduced the cumulative CO2 fluxes by 9.2%-21.6 % from the two soils, especially from WBF soil at low wetting intensity. The addition of glucose alone significantly increased soil heterotrophic respiration, microbial biomass C (MBC), and microbial metabolic quotient. The glucose-induced cumulative CO2 fluxes and soil MBC during the incubation ranged from 8.7 to 11.7 g CO2-C m-2 and from 7.4 to 23.9 g C m-2, which are larger than the dose of added C. Hence, the addition of external carbon can increase the decomposition of soil native organic C. The glucose-induced average and maximum rates of CO2 fluxes during the incubation were significantly in- fluenced by wetting intensity (WI) and vegetation type (VT), and by WIxVT, NH4ClxVT and WIxVTxNH4C1 (P〈0.05). The addition of NH4C1, instead of KNO3, significantly decreased the glucose-induced MBC of WBF soil (P〈0.05), whereas adding NH4C1 and KNO3 both significantly increased the glucose-induced MBC of BKPF soil at high moisture (P〈0.05). According to the differences in soil labile C pools, MBC and CO2 fluxes in the presence and absence of glucose, it can be concluded that the stimulating effects of glucose on soil heterotrophic respiration and MBC under temperate forests were dependent on vegetation type, soil moisture, and amount and type of the N added. 展开更多
关键词 dissolved organic carbon forest soil GLUCOSE heterotrophic respiration microbial biomass carbon nitrogen supply stimulating effect
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