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Relationship Between Leaf C/N Ratio and Insecticidal Protein Expression in Bt Cotton as Affected by High Temperature and N Rate 被引量:8
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作者 ZHANG Xiang LU Chun-hua +3 位作者 CHEN Yuan WANG Gui-xia CHEN Yuan CHEN De-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期82-88,共7页
Expression of insecticidal protein for transgenic Bacillus thuringiensis (Bt) cotton is unstable and related to nitrogen metabolism. The objective of this study was to investigate the relationship between leaf carbo... Expression of insecticidal protein for transgenic Bacillus thuringiensis (Bt) cotton is unstable and related to nitrogen metabolism. The objective of this study was to investigate the relationship between leaf carbon nitrogen ratio (C/N) and insecticidal efficacy of two Bt cotton cultivars. C/N ratio and Bt protein content were both measured at peak square period and peak boll period respectively under 5-7 d high temperature and different nitrogen fertilizer rates on the Yangzhou University Farm and the Ludong Cotton Farm, China. All plants were grown in field. The results showed that the C/N ratio enhanced slightly and the Bt protein content remained stable at peak square period, but significant increases for the C/N ratio and decreases markedly for the leaf Bt protein concentration were detected at the peak boll period. The similar patterns at the two growth periods were found for the leaf C/N ratio and Bt protein content by different N fertilizer treatments. When nitrogen rate was from 0 to 600 kg ha-l, the C/N ratio was reduced by 0.017 and 0.006 for Sikang 1 and Sikang 3 at peak square period, compared to the 1.350 to 1.143 reduction for Sikang 1 and Sikang 3 at peak boll period, respectively. Correspondingly, the leaf Bt protein contents were bolstered by 2.6-11.8 and 26.9-36.9% at the two different growth periods, respectively. The results suggested that enhanced C/N ratio by high temperature and nitrogen application may result in the reduction of inseetiocidal efficacy in Bt cotton, especially in peak boll period. 展开更多
关键词 Bt cotton C/N ratio Bt protein insecticidal efficacy
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Effect of carbon and nitrogen ratio control on Artemia growth, water quality, biofloc microbial diversity under high salinity and zero-water exchange culture condition 被引量:3
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作者 WANG Shanyue CUI Xueping +2 位作者 XU Ruyi GAO Meirong SUI Liying 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第5期1768-1776,共9页
Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces... Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces the nitrogen level in the water and provides microbial protein to the animals. However, most of the studies and practical applications have been conducted in freshwater and marine environment. This paper focused on brine shrimp Artemia that lives in high salinity environment together with other halophilic or halotolerant microorganisms. The effect of carbon supplementation on Artemia growth, water quality, and microbial diversity of biofl ocs was studied in the closed culture condition without any water exchange. The salinity of the culture medium was 100. A 24-d culture trial was conducted through supplementing sucrose at carbon/nitrogen (C/N) ratio of 5, 15, and 30 (Su5, Su15, and Su30), respectively. The culture without adding sucrose was used as a control. Artemia was fed formulated feed at a feeding ration of 60% recommended feeding level. The results showed that sucrose supplementation at higher C/N ratio (15 and 30) signifi cantly improved the Artemia survival, growth and water quality ( P <0.05). Addition of sucrose at C/N ratio of 15 and 30 significantly increased biofloc volume (BFV)( P <0.05). The Illumina MiSeq sequencing analysis showed that supplementing carbon at C/N ratio of 15 had a better total bacterial diversity and richness, and shaped the microbial composition at genera level. This study should provide information for studying the mechanism of biofloc technology and its application in high salinity culture conditions. 展开更多
关键词 biofl OCS C/N ratio ARTEMIA GROWTH water quality MICROBIAL diversity high throughput SEQUENCING
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Characteristics of Soil Organic Carbon, Total Nitrogen, and C/N Ratio in Chinese Apple Orchards 被引量:7
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作者 Shunfeng Ge Haigang Xu +1 位作者 Mengmeng Ji Yuanmao Jiang 《Open Journal of Soil Science》 2013年第5期213-217,共5页
Soil organic carbon and nitrogen are used as indexes of soil quality assessment and sustainable land use management. At the same time, soil C/N ratio is a sensitive indicator of soil quality and for assessing the carb... Soil organic carbon and nitrogen are used as indexes of soil quality assessment and sustainable land use management. At the same time, soil C/N ratio is a sensitive indicator of soil quality and for assessing the carbon and nitrogen nutrition balance of soils. We studied the characteristics of soil organic carbon and total nitrogen by investigating a large number of apple orchards in major apple production areas in China. High apple orchard soil organic carbon content was observed in the provinces of Heilongjiang, Xinjiang, and Yunnan, whereas low content was found in the provinces of Shandong, Henan, Hebei, and Shaanxi, with the values ranging between 6.44 and 7.76 g·kg-1. Similar to soil organic carbon, soil total nitrogen content also exhibited obvious differences in the 12 major apple producing provinces. Shandong apple orchard soil had the highest total nitrogen content (1.26 g·kg-1), followed by Beijing (1.23 g·kg-1). No significant difference was noted between these two regions, but their total nitrogen content was significantly higher than the other nine provinces, excluding Yunnan. The soil total nitrogen content for Xinjiang, Heilongjiang, Hebei, Henan, and Gansu was between 0.87 and 1.03 g·kg-1, which was significantly lower than that in Shandong and Beijing, but significantly higher than that in Liaoning, Shanxi, and Shaanxi. Six provinces exhibited apple orchard soil C/N ratio higher than 10, including Heilongjiang (15.42), Xinjiang (13.38), Ningxia (14.45), Liaoning (12.24), Yunnan (11.03), and Gansu (10.63). The soil C/N ratio was below 10 in the remaining six provinces, in which the highest was found in Shaanxi (9.47), followed by Beijing (8.98), Henan (7.99), and Shanxi (7.62), and the lowest was found in Hebei (6.80) and Shandong (6.05). Therefore, the improvement of soil organic carbon should be given more attention to increase the steady growth of soil C/N ratio. 展开更多
关键词 CHINESE APPLE ORCHARD Soil ORGANIC Carbon Total Nitrogen C/N ratio
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Evaluation on nitrogen isotopes analysis in high-C/N-ratio plants using elemental analyzer/isotope ratio mass spectrometry 被引量:2
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作者 胡婧 刘卫国 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第2期36-39,共4页
Elemental analyzer/isotope ratio mass spectrometry(EA/TRMS) has been widely applied to analyze the^(15)N/^(14)N isotope composition(δ^(15)N) of plants and soils,but the δ^(15)N results may be inaccurate due to incom... Elemental analyzer/isotope ratio mass spectrometry(EA/TRMS) has been widely applied to analyze the^(15)N/^(14)N isotope composition(δ^(15)N) of plants and soils,but the δ^(15)N results may be inaccurate due to incomplete combustion of the high-C/N-ratio plant samples by EA.Therefore,it is necessary to develop a method to solve the problem of imperfect combustion.In this study,we used two methods:1) adding copper oxide powder to the samples,and 2) increasing the O_2 flow(from 100 mL min^(-1) to 200 mL min^(-1)) for the auto sampler inlet purge line of the EA.The δ^(15)N values of the plant samples became more positive and tended to be stable after complete combustion.Also,the required blank samples for each plant sample decreased with increasing amount of the added CuO powder.However,at 200 mL min^(-1) of the oxygen flow in the EA,complete combustion could not be achieved without adding copper oxide,but this was done with decreased amount of CuO powder.Therefore,mixing cupric oxide into the high-C/N-ratio samples was an efficient,simple and convenient way to solve the problem of imperfect combustion in the EA. 展开更多
关键词 同位素分析 植物样品 元素分析仪 质谱仪 同位素比值 不完全燃烧 评价 铜粉末
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Effects of Elevated CO_2 Concentration on the Biomasses and Nitrogen Concentrations in the Organs of Sainfoin(Onobrychis viciaefolia Scop.) 被引量:1
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作者 ZHOU Zheng-chao SHANGGUAN Zhou-ping 《Agricultural Sciences in China》 CAS CSCD 2009年第4期424-430,共7页
In forage grasses, the nitrogen concentration is directly related to the nutritional value. The studies examined the hypothesis that global elevation of CO2 concentration probably affects the biomass, nitrogen (N) c... In forage grasses, the nitrogen concentration is directly related to the nutritional value. The studies examined the hypothesis that global elevation of CO2 concentration probably affects the biomass, nitrogen (N) concentration, and allocation and distribution patterns in the organs of forage grasses. While sainfoin (Onobrychis viciaefolia Scop.) seedlings grew on a low nutrient soil in closed chambers for 90 days, they were exposed to two CO2 concentrations (ambient or ambient+350 μmol mol^-1 CO2) without adding nutrients to them. After 90 days exposure to CO2, the biomasses of leaves, stems, and roots, and N concentrations and contents of different parts were measured. Compared with the ambient CO2 concentration, the elevated CO2 concentration increased the total dry matter by 25.07%, mainly due to the root and leaf having positive response to the elevated CO2 concentration. However, the elevated CO2 concentration did not change the proportions of the dry matters in different parts and the total plants compared with the ambient CO2 concentration. The elevated CO2 concentration lowered the N concentrations of the plant parts. Because the dry matter was higher, the elevated CO2 concentration had no effect on the N content in the plants compared to the ambient CO2 concentration. The elevated CO2 concentration promoted N allocations of the different parts significantly and increased N allocation of the underground part. The results have confirmed the previous suggestions that the elevated CO2 concentration stimulates plant biomass production and decreases the N concentrations of the plant parts. 展开更多
关键词 BIOMASS CO2 N allocation N content C/N ratio SAINFOIN
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Influence of Different C/N Ratios on Aerobic Denitrification Characteristics of the Strain 被引量:1
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作者 Haoning Wang Xiulan Ma Yi Li 《Meteorological and Environmental Research》 CAS 2013年第10期22-24,共3页
[ Objective] The research aimed to study influence of different C/N ratios on aerobic denitdfication characteristics of the strain. [ Method] 5 aerobic denitdfying bacteria were isolated from activated sludge at low t... [ Objective] The research aimed to study influence of different C/N ratios on aerobic denitdfication characteristics of the strain. [ Method] 5 aerobic denitdfying bacteria were isolated from activated sludge at low temperature and low C/N ratio, and their denitdfication capabilities were verified. Influence of different C/N ratios on denitdfication capability of the strain was determined. [ Result] In the five isolated aerobic denitdf- ying bacteria, except HFX08 was G-, HFX00, HFX01, HFX12 and HFX13 were G +. HFX08 belonged to Pseudomonas, and other strains be- longed to Acinetobacter. As C/N ratio increased, denitdfication velocity increased, and the highest removal rate of nitrogen for the five strains could reach over 92%. [ Conclusion] The research could provide reference for design and operation of the sewage treatment process with low C/N ratio in winter in the north. 展开更多
关键词 C/N ratio Aerobic denitdfication Removal rate of the nitrogen China
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Amelioration of Saline Soil by the Application of Gypsum, Calcium Chloride, Rice Husk and Cow Dung 被引量:1
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作者 Mohammad Zulfikar Khan Mohammad Golam Azom +5 位作者 Mohammad Tipu Sultan Sudipta Mandal Mohammad Ariful Islam Rikta Khatun Shaikh Motasim Billah Abu Hena Mohammad Zulfikar Ali 《Journal of Agricultural Chemistry and Environment》 2019年第2期78-91,共14页
A pot experiment was conducted to investigate the effect of cow dung, rice husks, calcium chloride and gypsum on soil reclamation and compare the effect of organic and inorganic amendments on soil reclamation during t... A pot experiment was conducted to investigate the effect of cow dung, rice husks, calcium chloride and gypsum on soil reclamation and compare the effect of organic and inorganic amendments on soil reclamation during the period of 5th March to 20th April, 2017. The experiment was laid to fit a completely randomized design (CRD) with seven treatments [Reference soil (T0), Cow dung (T1), Rice husk (T2), Gypsum (T3), Calcium chloride (T4), Cow dung + Rice husk (T5) and Gypsum + Calcium chloride (T6)] each having three replications for this experiment. After incubation (45 days), the laboratory investigation was carried out in the Soil, Water and Environment Discipline, Khulna University, Khulna, Bangladesh. Results indicate that the individual or combined effect of gypsum (T3) was more effective in changing EC and SAR. Gypsum application in combination with calcium chloride (T6) improved the soil chemical properties by reducing the EC. Among the treatment, calcium chloride (T4) had a remarkable effect in reducing sodium adsorption ratio and gypsum had a remarkable effect in reducing pH. Cow dung (T1), rice husk (T2), combination of cow dung and rice husk (T5) were less effective to reduce EC, pH and SAR. It’s measured for soils of different soil amendments varied significantly 展开更多
关键词 AMELIOratioN SALINE Soil COW DUNG Rice Husk GYPSUM Calcium Chloride C/N ratio
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Effects of Soil C/N Ratio on Apple Growth and Nitrogen Utilization,Residue and Loss
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作者 Shunfeng GE Yihua REN +4 位作者 Ling PENG Haigang XU Mengmeng JI Shaochong WEI Yuanmao JIANG 《Asian Agricultural Research》 2014年第2期69-72,76,共5页
Soil C /N ratio is an important influencing factor in soil nitrogen cycling. Two-year old apple trees( Borkh. cv. ‘Fuji'/Malus hupehensis) were used to understand the effect of soil C/N ratio [6. 52( CK),10,15,20... Soil C /N ratio is an important influencing factor in soil nitrogen cycling. Two-year old apple trees( Borkh. cv. ‘Fuji'/Malus hupehensis) were used to understand the effect of soil C/N ratio [6. 52( CK),10,15,20,25,30,35 and 40]on apple growth and nitrogen utilization and loss by using15N trace technique. The results showed that,with the increasing of soil C/N ratio,apple shoot length and fresh weight increased at first,and then decreased; the higher apple shoot length and fresh weight appeared in C/N = 15,20 and 25 treatments,and there were no significant differences among these three treatments,but significantly higher than the other treatments. Statistical analysis revealed that there was significant difference in nitrogen utilization rate between the different treatments,the highest N utilization rate was occurred in soil C/N = 25 treatment which value was 22. 87%,and there was no significant difference between soil C/N = 25 and C/N = 20 treatments,but both the two treatments were significantly higher than the other treatments; Soil C/N = 40 had the lowest N utilization rate which value was 15. 43%,and this value was less than CK( 16. 65%). The proportion of plant absorption nitrogen from fertilizer was much higher when the value of soil C/N ratio in the range of 15- 25,but the percentage of plant absorption nitrogen from soil was much higher when the soil C/N ratio was too low( < 15) or high( < 25). Amount of residual nitrogen in soil increased gradually with the soil C/N ratio increasing,the amount of residual nitrogen in C/N = 40 treatment was 1. 32 times than that in CK. With the increasing of soil C/N ratio,fertilizer nitrogen loss decreased at first,and then increased,fertilizer nitrogen loss was the minimum in C/N = 25 treatments( 49. 87%) and the maximum were occurred in CK( 61. 54%). Therefore,regarding the apple growth and nitrogen balance situation,the value of soil C/N ratio in the range of 15- 25 would be favorable for apple growth and could increase effectively nitrogen fixed by soil,reduce nitrogen loss,and improve the nitrogen utilization ratio. 展开更多
关键词 SOIL C/N ratio APPLE 15N Nitrogen UTILIZATION Nitr
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Effect of C/N Ratio on DHA Production by Schizochytrium sp.JN-3 and Its Pilot-scale Fermentation
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作者 Xiaole XIA Hailing YANG +3 位作者 Yuji LI Ling ZHANG Yu XIN Wu WANG 《Agricultural Biotechnology》 CAS 2012年第1期51-53,57,共4页
[ Objective] This study aimed to explore the effect of C/N ratio on DHA production by Schizochytrium sp. , and the results were verified by pilot-scale fermentation. [ Method] Effect of C/N ratio on DHA production by ... [ Objective] This study aimed to explore the effect of C/N ratio on DHA production by Schizochytrium sp. , and the results were verified by pilot-scale fermentation. [ Method] Effect of C/N ratio on DHA production by Schizochytrium sp. JN-3 was explored. The industrial fermentation potential of Schizochytrium sp. JN-3 was investigated by pilot-scale fermentation in a 200 L fermentation tank. [ Result] Results of fermentation in a 7 L fermentation tank showed that the maximum biomass and total lipid content were 34.3 and 20.1 g/L, respectively, when C/N ratio was 10 ; the maximum DHA yield was 46.9% when C/N ratio was 20. When pilot-scale fermentation was conducted in a 200 L fermentation tank, the biomass was 30. 2 g/L, total lipid content was 18.4 g/L, accounting for 63.2% of the dry weight of cells; DHA content was 7.4 g/L, accounting for 40. 2% of the total lipid content. [ Condasion ] Schizochytrlum sp. JN-3 has good industrial fermentation notential. 展开更多
关键词 Schizochytrium sp. DHA C/N ratio Pilot-scale fermentation
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油茶壳-蚕沙不同碳氮比堆肥的腐熟效果
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作者 蒋越华 范稚莲 +5 位作者 时鹏涛 李鸿 吴凤 黄海连 杨丹亚 莫良玉 《贵州农业科学》 CAS 2024年第8期52-61,共10页
【目的】探明油茶壳-蚕沙不同碳氮比(C/N)堆肥的腐熟效果,为油茶壳和蚕沙无害化、资源化利用提供依据。【方法】以油茶壳与蚕沙为堆肥原料进行好氧堆肥试验,研究不同碳氮比油茶壳-蚕沙堆肥处理(CK:纯油茶壳50 kg,C/N=100;T_(1):油茶壳50... 【目的】探明油茶壳-蚕沙不同碳氮比(C/N)堆肥的腐熟效果,为油茶壳和蚕沙无害化、资源化利用提供依据。【方法】以油茶壳与蚕沙为堆肥原料进行好氧堆肥试验,研究不同碳氮比油茶壳-蚕沙堆肥处理(CK:纯油茶壳50 kg,C/N=100;T_(1):油茶壳50 kg,蚕沙45 kg,C/N=20;T_(2):油茶壳50 kg,蚕沙31 kg,C/N=25;T_(3):油茶壳50 kg,蚕沙23 kg,C/N=30;T_(4):油茶壳50 kg,蚕沙18 kg,C/N=35)堆肥过程中物理、化学和生物指标的变化。【结果】与CK比,不同C/N油茶壳-蚕沙处理pH呈中性或弱碱性,且最高温度和高温持续时间均较高,其中,C/N=20和C/N=25的油茶壳-蚕沙处理高温持续时间分别为17 d和13 d,达《畜禽粪便无害化处理技术规范》(NY/T 1168—2006)要求。不同C/N油茶壳-蚕沙处理的C/N、有机质、木质素和纤维素含量均随发酵进程而逐渐降低,全氮、全磷和全钾含量均有所增加,堆肥发酵结束时,C/N=20和C/N=25油茶壳-蚕沙处理的总养分含量较高,分别为5.10%和4.28%,符合《有机肥料》(NY/T 525—2021)要求;有机质、纤维素、木质素的降幅较大,分别降17.1百分点、11.2百分点、8.4百分点和15.8百分点、6.8百分点、6.3百分点;GI均稳定在70%以上,对植物毒性小。不同C/N油茶壳-蚕沙处理堆肥后的重金属(Pb、Cd、Cr、As、Hg)含量较堆肥前均有所提高,但均低于标准限量值。【结论】添加适量比例的蚕沙可有效促进油茶壳腐解,调节堆肥初始C/N在20~25有利于油茶壳-蚕沙堆肥的腐熟。 展开更多
关键词 油茶壳 蚕沙 碳氮比 堆肥 腐熟 有机质 纤维素 木质素
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耐高渗青春双歧杆菌的筛选及发酵工艺优化 被引量:1
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作者 潘子怡 毛丙永 +3 位作者 唐鑫 张秋香 赵建新 崔树茂 《食品与发酵工业》 CAS CSCD 北大核心 2024年第3期30-37,共8页
为解决青春双歧杆菌在生产中发酵密度低的问题,该文测定了94株青春双歧杆菌的耐渗能力,同时评价了耐高渗菌株耐渗能力的遗传稳定性,最后通过解析培养基底物和发酵工艺探究了耐高渗菌株的最适发酵条件,从而提高其生产中的发酵活菌数。筛... 为解决青春双歧杆菌在生产中发酵密度低的问题,该文测定了94株青春双歧杆菌的耐渗能力,同时评价了耐高渗菌株耐渗能力的遗传稳定性,最后通过解析培养基底物和发酵工艺探究了耐高渗菌株的最适发酵条件,从而提高其生产中的发酵活菌数。筛选得到两株最高可耐受1400 mOsm/kg的菌株CCFM1302和CCFM1066,其最优氮源为复合氮源(胰酪蛋白胨和酵母浸粉FM528以质量比1∶1复合),最优碳氮比分别为(2.71±0.23)∶1和(2.53±0.11)∶1。以达到完全抑制渗透压为发酵终点推算底物最适浓度,进一步优化微量元素的添加量,得到最优培养基:复合氮源21.0 g/L、葡萄糖57.0 g/L(CCFM1302),复合氮源22.4 g/L、葡萄糖56.5 g/L(CCFM1066);此外添加MgSO_(4)·7H_(2)O 0.25 g/L,半胱氨酸1 g/L、吐温801 mL/L。恒pH 5.5培养至稳定期发酵液活菌数可达(1.82±0.08)×10^(10)CFU/mL和(1.70±0.03)×10^(10)CFU/mL。该文筛选到可产业化的两株青春双歧杆菌,并优化其高密度发酵工艺,对生产和应用都具有重要意义。 展开更多
关键词 青春双歧杆菌 渗透压 高密度培养 碳氮比 活菌数
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The Relationships between Erythrocyte Membrane n-6 to n-3 Polyunsaturated Fatty Acids Ratio and Blood Lipids and C-reactive Protein in Chinese Adults:An Observational Study
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作者 ZHANG Bo WANG Ping +6 位作者 ZHOU Quan CHEN ChaoGang ZHUO ShuYu YE YanBin HE QiQiang CHEN YuMing SU YiXiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第3期234-242,共9页
Objective To investigate the relationships between erythrocyte membrane n-6:n-3 PUFAs ratio and blood lipids and high sensitivity C-reactive protein (hs-CRP). Methods The Chinese and a observational study consisted... Objective To investigate the relationships between erythrocyte membrane n-6:n-3 PUFAs ratio and blood lipids and high sensitivity C-reactive protein (hs-CRP). Methods The Chinese and a observational study consisted of a population-based cross-sectiona subsequent 1-year follow-up study of 171 subjects with the fasting cholesterol of 5.13-8.00 mmol/L. study of 456 plasma total Results In the cross-sectional analysis, plasma low-density lipoprotein cholesterol (LDL-c) had a significant and negative association with the erythrocyte membrane n-6:n-3 PUFAs ratio (P for trend=0.019) after adjusting for sex, age and total PUFA percentage. In the follow-up study, 171 subjects were categorized into quartiles by the changes of n-6:n-3 ratio in erythrocyte membrane (△=month 12-month 0). In the top quartile whose ratios of n-6:n-3 increased by an average of 1.25 during the follow-up, the LDL-c-lowering extent was 3.3 times of that in the lowest quartile whose ratios of n-6:n-3 decreased by an average of 1.13 (-1.07 mmol/L v.s. -0.32 mmol/L). The hsCRP decreased by 0.11 mg/dL in the lowest quartile while increasing by 0.10 mg/dL in the top quartile (P for difference=0.052). Conclusion Our results suggested that the balance between n-6 and n-3 fatty acids may optimize the cardiovascular benefits from dietary PUFAs. 展开更多
关键词 Erythrocyte membrane n-6:n-3 fatty acids ratio Blood lipids High sensitivity C-reactiveprotein Observational study
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柑橘大豆间作对土壤团聚体结构及其有机碳、氮分布的影响
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作者 曹胜 曾斌 +4 位作者 邓素枫 龚碧涯 张文 罗赛男 杨水芝 《土壤》 CAS CSCD 北大核心 2024年第4期735-741,共7页
探讨柑橘大豆不同间作年限下土壤团聚体结构及有机碳、氮分布差异,旨在为果园土壤改良提供参考。通过田间定位试验设置清耕区(CK)、柑橘间作大豆1年(T1)、柑橘间作大豆2年(T2)和柑橘间作大豆3年(T3)4个处理,测定土壤团聚体组成、稳定性... 探讨柑橘大豆不同间作年限下土壤团聚体结构及有机碳、氮分布差异,旨在为果园土壤改良提供参考。通过田间定位试验设置清耕区(CK)、柑橘间作大豆1年(T1)、柑橘间作大豆2年(T2)和柑橘间作大豆3年(T3)4个处理,测定土壤团聚体组成、稳定性、有机碳和全氮等指标。结果表明:①与清耕柑橘园相比,柑橘间作大豆的土壤>0.25 mm大团聚体含量提高了19.58%~22.29%;②柑橘间作大豆的土壤团聚体稳定性特征表现为:T3>T2>T1>CK;③团聚体粒径中的有机碳和全氮含量表现为>5 mm粒径最高,<0.25 mm粒径含量最低,柑橘间作大豆的土壤C/N值较清耕区提高了1.16倍~1.19倍;④土壤团聚体组成与团聚体有机碳和全氮含量的相关性显著,RDA分别解释99.32%和94.99%的差异信息,其中>5、5~2和0.5~0.25 mm粒径土壤团聚体是影响土壤有机碳和全氮含量变化的主要环境因子。总体而言,柑橘园行间间作大豆可增加土壤肥力,改善土壤团聚体结构,是一种可持续农业发展模式。 展开更多
关键词 柑橘园 大豆 间作 土壤团聚体 有机碳 全氮 C/N
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鱼蛋白作为激发剂促进还田秸秆腐解和有机碳在土壤中积累
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作者 刘心雨 黄程鹏 +2 位作者 姜培坤 陈瑾 徐秋芳 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第1期74-86,共13页
[目的]秸秆还田量影响秸秆腐解、后茬作物生长和温室气体排放。研究不同秸秆还田量下,利用鱼蛋白作为激发剂促进秸秆分解、提高土壤有机碳积累的效果,为秸秆和鱼蛋白资源的合理高效利用提供理论依据。[方法]采用室内培养试验方法,设置... [目的]秸秆还田量影响秸秆腐解、后茬作物生长和温室气体排放。研究不同秸秆还田量下,利用鱼蛋白作为激发剂促进秸秆分解、提高土壤有机碳积累的效果,为秸秆和鱼蛋白资源的合理高效利用提供理论依据。[方法]采用室内培养试验方法,设置秸秆还田量、有机激发剂种类及其在总激发剂中的占比3个因素。秸秆还田量包括适量(7500 kg/hm^(2))和高量(10500 kg/hm^(2))两个水平;供试有机激发剂包括猪粪、鱼蛋白;猪粪、鱼蛋白激发剂添加量占尿素氮量的比例分别为50%、100%(分别记为P50、F50、P100、F100),以两个秸秆还田量不添加激发剂处理为对照,共10个处理。激发剂总量按照调节投入秸秆碳氮比为35:1所需要的氮量计算,其中50%和100%的氮量由猪粪、鱼蛋白提供,培养期为60天。培养期间测定CO_(2)和N_(2)O排放速率及累计排放量。培养结束时,测定土壤养分含量、细菌和真菌丰度以及酶活性。[结果]高量秸秆还田虽然可增加土壤中有机碳的积累,但土壤CO_(2)排放量以及单位输入碳的排放量均高于适量秸秆还田土壤。培养前13天,高量和适量秸秆还田的累计CO_(2)排放量占总排放量的40%以上,以F50处理排放量最高。P50和F50处理适量和高量秸秆还田土壤CO_(2)排放总量低于P100和F100处理,而N_(2)O排放正好相反,P50和F50处理土壤有机碳积累也高于P100和F100处理。适量秸秆还田条件下,F50处理的CO_(2)排放速率和N_(2)O排放总量均高于P50;而CO_(2)排放总量显著低于P50,土壤中有机碳积累量显著高于P50处理。适量秸秆还田土壤细菌和真菌丰度总体高于高量秸秆还田土壤;P50和F50处理土壤酶活性总体高于激发剂100%添加处理,F50处理的效果优于P50处理。[结论]高量秸秆还田显著增加CO_(2)排放总量,降低单位碳投入量的土壤有机碳积累量。适量秸秆还田(7500 kg/hm^(2))条件下,以鱼蛋白提供调节碳氮比所需氮量的50%处理较传统猪粪处理可显著提高早期CO_(2)排放速率,降低CO_(2)排放总量,提升土壤有机碳积累量,因此,可作为提高还田秸秆腐解的有效措施。 展开更多
关键词 秸秆还田 碳氮比 激发剂 碳积累 温室气体排放
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外源有机肥碳氮比对植烟红壤微环境及烟叶品质的影响
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作者 张晓伟 杨宗云 +4 位作者 倪明 赵新梅 王炽 杨树明 徐兴阳 《中国农学通报》 2024年第11期49-54,共6页
碳氮比是反映有机肥肥效的重要指标之一。探讨有机肥碳氮比对烤烟根际土壤微环境及烟叶产质量的影响,为土壤培肥及其可持续管理提供科学依据。2021—2022年在云南省寻甸酸性山原红壤上,以烤烟‘云烟87’为材料,采用大田试验,研究等氮磷... 碳氮比是反映有机肥肥效的重要指标之一。探讨有机肥碳氮比对烤烟根际土壤微环境及烟叶产质量的影响,为土壤培肥及其可持续管理提供科学依据。2021—2022年在云南省寻甸酸性山原红壤上,以烤烟‘云烟87’为材料,采用大田试验,研究等氮磷钾条件下施无机化肥对照(T1,CK),以及配施不同碳氮比有机肥(10:1、15:1、20:1、25:1)对植烟土壤肥力、土壤团聚体、微生物群落及烟叶产质量的影响。结果表明:与CK相比,T2、T3、T5土壤pH升高0.09~0.13个单位;T2、T3、T4、T5显著增加土壤有机质、水解性氮、有效磷及有机碳含量,分别提高9.91%~17.40%、9.11%~16.45%、7.16%~43.68%、11.61%~39.54%;T2、T3土壤速效钾含量较CK显著提高8.12%、14.63%。T2、T3、T4、T5的土壤SOC含量及C/N较CK分别显著提高11.61%~39.54%、4.48%~29.72%。T2、T3、T4、T5的大粒径团聚体(>5、2~5、1~2 mm)含量显著增加20.75%~75.91%、10.06%~54.50%和16.98%~66.13%;而其微团聚体(0.053~0.25、<0.053 mm)含量较CK显著下降10.61%~54.52%;土壤真菌、细菌、放线菌及微生物量碳、氮含量均显著增加。T2、T3可促进烟株生长,其叶面积较CK分别显著增加7.36%和14.92%。与CK相比,T2、T3的产量和产值分别显著提高11.99%、16.93%及5.92%、15.46%。T3能显著增加烟叶总糖、还原糖和钾含量,降低总氮和烟碱含量,烟叶化学成分较协调。施碳氮比(10:1、15:1)的有机肥有利于提升土壤pH及土壤肥力,改善土壤团聚体结构和稳定性,增加土壤微生物数量及微生物群落丰度,促进烤烟发育,提高烟叶产值和品质。 展开更多
关键词 烤烟 碳氮比 有机肥 团聚体结构 品质
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高碳基肥减氮施用对植烟土壤总碳、总氮和真菌群落结构的影响
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作者 赵纪 李航 +8 位作者 苏梦迪 胡丽涛 敖飞 黄浪平 傅春梅 罗钧钊 陈军华 马啸 张松涛 《山东农业科学》 北大核心 2024年第10期93-101,共9页
本研究采用田间试验法,以常规施肥(纯氮111 kg·hm^(-2))为对照(GCK),设置高碳基肥450 kg·hm^(-2)+减氮10%(G3)、高碳基肥750 kg·hm^(-2)+减氮20%(G5)和高碳基肥1050 kg·hm^(-2)+减氮30%(G7)共4个处理,研究其对植烟... 本研究采用田间试验法,以常规施肥(纯氮111 kg·hm^(-2))为对照(GCK),设置高碳基肥450 kg·hm^(-2)+减氮10%(G3)、高碳基肥750 kg·hm^(-2)+减氮20%(G5)和高碳基肥1050 kg·hm^(-2)+减氮30%(G7)共4个处理,研究其对植烟土壤总碳、总氮含量的影响,并采用ITS测序技术分析烟田土壤真菌群落结构及其与土壤总碳和总氮的关系。结果表明:(1)高碳基肥减氮施用处理G7提高植烟土壤总碳含量和碳氮比(移栽后60、90 d),降低土壤总氮含量(移栽后60、90 d)。(2)高碳基肥减氮施用处理G3显著提高土壤真菌丰富度(移栽后30、90 d)。(3)高碳基肥减氮施用改变了真菌的群落结构,在门水平上提高了接合菌门(Zygomycota)相对丰度(移栽后60 d),降低了子囊菌门(Ascomycota)相对丰度;在属水平上提高了木霉属(Trichoderma)相对丰度,降低了镰刀菌属(Fusarium)相对丰度(移栽后60 d)。(4)高碳基肥减氮施用通过影响土壤总碳、总氮含量和碳氮比改变其真菌多样性和群落结构。本试验条件下,每公顷施用高碳基肥1050 kg+纯氮77.7 kg(G7)对植烟土壤总碳、总氮、碳氮比以及真菌群落结构影响较大。 展开更多
关键词 高碳基肥 减氮施用 总碳 总氮 碳氮比 真菌群落结构 植烟土壤
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凋落物C/N对土壤有机碳矿化的影响
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作者 李天 苗淑杰 +2 位作者 余洁 赵玉蝶 乔云发 《生态环境学报》 CSCD 北大核心 2024年第11期1686-1695,共10页
凋落物输入会影响土壤有机碳(SOC)矿化过程,其影响程度主要受凋落物C/N、土壤肥力和温度条件的影响,然而,这三因素的综合影响仍不清楚。以低肥力土壤(LF)和高肥力土壤(HF)为研究对象,分别添加7种不同C/N的凋落物,并设置培养温度为23℃... 凋落物输入会影响土壤有机碳(SOC)矿化过程,其影响程度主要受凋落物C/N、土壤肥力和温度条件的影响,然而,这三因素的综合影响仍不清楚。以低肥力土壤(LF)和高肥力土壤(HF)为研究对象,分别添加7种不同C/N的凋落物,并设置培养温度为23℃和33℃,进行恒温避光培养,期间动态监测CO_(2)排放的变化,以揭示SOC矿化过程应对三因子的响应机制。结果显示,凋落物添加显著增加CO_(2)峰值排放速率,且与C/N>30的凋落物相比,添加C/N<30的凋落物对CO_(2)的峰值排放速率的促进作用更显著。CO_(2)峰值排放速率同时受土壤肥力和培养温度影响,HF-33℃条件下的CO_(2)峰值排放速率最高。添加C/N<30的凋落物显著增加了CO_(2)累积排放量,在LF-23℃、LF-33℃、HF-23℃和HF-33℃条件下,最大增幅分别为407%、304%、345%和160%。相关分析显示,SOC矿化率与凋落物C/N间呈负相关关系,这说明低质量凋落物会抑制SOC矿化。在LF-23℃、LF-33℃、HF-23℃和HF-33℃处理下,与凋落物C/N最低的CN1相比,添加C/N最高的CN7后,SOC矿化率的降幅分别达3.53、3.04、1.71和2.06倍。土壤肥力影响SOC矿化,HF的SOC矿化率较LF高1.29-2.66倍。培养温度对SOC矿化的影响在HF中表现出显著差异,与CK相比,在HF中添加凋落物显著降低了SOC矿化温度敏感性(Q10)。综合PLS-PM模型可知,SOC矿化是凋落物C/N、土壤肥力和培养温度综合作用的结果。其中,凋落物的C/N比对SOC矿化产生显著的负效应,土壤肥力则对SOC矿化产生主要的正效应,而温度的正效应则相对较小。研究结果有助于进一步理解不同土壤肥力和温度背景下,C/N不同的外源有机物输入对SOC矿化的影响及其背后的综合效应。 展开更多
关键词 凋落物输入 凋落物碳氮比 有机碳矿化 CO_(2)释放速率 室内培养 温度敏感性
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不同碳氮比杨梅枝条堆肥的养分含量和细菌群落变化
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作者 邹秀琴 赵承森 +5 位作者 娄钰静 丁枫华 戴庆敏 袁国印 程陈 朱阳春 《中国南方果树》 北大核心 2024年第2期103-111,共9页
为了研究不同碳氮比对杨梅枝条堆肥发酵过程中养分、腐殖质组分及细菌群落结构的影响,设置碳氮比分别为30∶1、60∶1,90∶1进行杨梅枝条堆肥发酵试验,测定各处理养分和腐殖质组分,对细菌群落采用细菌16S rRNA Illumina Miseq高通量测序... 为了研究不同碳氮比对杨梅枝条堆肥发酵过程中养分、腐殖质组分及细菌群落结构的影响,设置碳氮比分别为30∶1、60∶1,90∶1进行杨梅枝条堆肥发酵试验,测定各处理养分和腐殖质组分,对细菌群落采用细菌16S rRNA Illumina Miseq高通量测序,比较细菌相对丰度,分析细菌群落Alpha和Beta多样性,及堆肥养分因子与细菌群落相关性。结果表明,杨梅枝条堆料处理的全氮、全磷、全钾含量随碳氮比增加而减少,有机质和胡敏素含量随碳氮比增加而增加;全氮、全钾、胡敏酸和富里酸含量随发酵时间延长显著增加,有机质和胡敏素含量则显著减少(p<0.05);碳氮比与有机质、全氮和胡敏素呈极显著相关。3个处理的厚壁菌门和放线菌门细菌的相对丰度随碳氮比增加而增加,变形菌门和拟杆菌门细菌的相对丰度随碳氮比增加而减少;在高温阶段厚壁菌门和放线菌门细菌的相对丰度明显高于其他阶段。不同碳氮比处理的细菌群落丰富度和多样性存在明显差异。碳氮比对枝条堆体细菌群落结构起决定性作用,全氮、有机质和温度也对枝条堆体细菌群落结构有一定的影响。堆体细菌群落结构与碳氮比、全氮和有机质之间存在显著相关性。说明碳氮比对杨梅枝条堆肥养分含量和细菌群落分布具有关键性作用。 展开更多
关键词 堆肥 碳氮比 杨梅 有机质 腐殖质 细菌相对丰度
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等碳量不同有机物料添加对红壤团聚体组分分布及有机碳、氮含量的影响
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作者 吴艳 宋惠洁 +6 位作者 胡丹丹 徐小林 胡志华 冀建华 黄尚书 黄建清 柳开楼 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第4期556-564,共9页
由于土壤理化性质不同,不同肥力的红壤上适宜的有机物料种类可能存在差异。为精准分类指导不同肥力红壤选择适宜的有机物料种类,选择长期进行花生、油菜轮作的红壤旱地,采集0~20和>20~40 cm深度土壤样品,分别代表高肥力和低肥力土壤... 由于土壤理化性质不同,不同肥力的红壤上适宜的有机物料种类可能存在差异。为精准分类指导不同肥力红壤选择适宜的有机物料种类,选择长期进行花生、油菜轮作的红壤旱地,采集0~20和>20~40 cm深度土壤样品,分别代表高肥力和低肥力土壤,设置不施有机碳(C0)以及施用油菜秸秆碳(OSC)、水稻秸秆碳(RSC)、玉米秸秆碳(MSC)、猪粪碳(PMC)处理,其中各有机物料处理的碳投入量相同,进行连续90 d的避光培养,测定不同处理团聚体组分及有机碳、氮含量,分析有机物料投入C/N比与团聚体组分C/N比的相关关系。结果表明:(1)与C0对照相比,各有机物料处理均显著提高了>2 mm团聚体比例。在高肥力土壤中,OSC、RSC、MSC和PMC处理>2 mm团聚体组分比例分别增加217.89%、283.97%、286.63%和210.63%,低肥力土壤中上述处理的增幅分别为72.25%、84.45%、72.11%和46.47%。(2)有机物料投入后,>2、>0.25~2、≥0.053~0.25和<0.053 mm团聚体组分有机碳含量均显著提升,但不同肥力土壤中各有机物料处理下团聚体组分有机碳的增幅差异较大,以>2 mm团聚体组分有机碳为例,高肥力土壤表现为RSC和MSC处理较高,而低肥力土壤则表现为OSC处理较高。(3)高肥力和低肥力土壤中添加不同有机物料均显著增加了>0.25~2和<0.053 mm团聚体组分全氮含量,且各处理均大体呈现出PMC处理最高的趋势。(4)在高肥力和低肥力土壤中添加不同有机物料均增加了团聚体组分C/N比,但高肥力和低肥力土壤中存在明显分异。以>0.25~2 mm团聚体组分C/N比为例,高肥力土壤表现为OSC、RSC和MSC处理较高;而低肥力土壤则表现为RSC和MSC处理较高,且大体呈现出PMC处理下土壤团聚体组分C/N比显著低于其他有机物料处理的趋势。(5)高肥力土壤中,提高有机物料C/N比可显著增加土壤>2和>0.25~2 mm团聚体组分C/N比;而低肥力土壤中,仅>0.25~2 mm团聚体组分C/N比与有机物料投入C/N比呈显著正相关。结合拟合方程的斜率分析发现,当投入有机物料的C/N比增加时,高肥力土壤中>0.25~2 mm团聚体组分C/N比的增幅明显小于低肥力土壤。与猪粪相比,秸秆类有机物料对团聚体碳、氮积累的促进效果较好。建议参考土壤肥力水平精准调控投入有机物料的C/N比,以期合理提升土壤团聚体组分的C/N比。 展开更多
关键词 有机物料种类 土壤肥力水平 团聚体组分 C/N比
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膜曝气生物膜反应器脱氮性能研究
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作者 任志鹏 陈小光 +1 位作者 唐崇俭 陆慧锋 《工业水处理》 CAS CSCD 北大核心 2024年第2期112-117,共6页
膜曝气生物膜反应器(MABR)有效地将生物膜法技术和膜分离技术结合在一起,在污水脱氮方面潜力巨大。以MABR处理模拟生活污水和豆制品加工废水,着重考察了MABR的稳定性及脱氮性能。结果表明,在HRT=12 h、曝气压力=10 kPa和C/N=5时,MABR对... 膜曝气生物膜反应器(MABR)有效地将生物膜法技术和膜分离技术结合在一起,在污水脱氮方面潜力巨大。以MABR处理模拟生活污水和豆制品加工废水,着重考察了MABR的稳定性及脱氮性能。结果表明,在HRT=12 h、曝气压力=10 kPa和C/N=5时,MABR对模拟生活污水处理效果最佳,COD、氨氮、TN的平均去除率分别为92.0%、86.5%、83.3%。而在HRT=8 h和曝气压力=10 kPa时,MABR对豆制品加工废水处理效果最佳,COD、氨氮、TN的容积负荷分别为1320、125.5、184 g(/m^(3)·d),平均去除率分别可达到84.2%、81.5%、79.7%,优于传统生物膜法脱氮。 展开更多
关键词 膜曝气生物膜反应器 脱氮 碳氮比 曝气压力 豆制品加工废水
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