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软件开发新技术在土壤碳呼吸实时监测系统中的应用
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作者 任涛 张磊 +1 位作者 杨柯 刘国栋 《电脑编程技巧与维护》 2016年第1期25-27,共3页
研究以土壤碳呼吸作为工作基础,充分分析了仪器数据格式,总结了传输数据流中的关键字(项目主要监测数值土壤碳通量的关键字为EXPFLUX),并基于.NET技术开发了实时传输数据解析软件,解决了研究过程中的国外仪器数据传输解析的问题。利用... 研究以土壤碳呼吸作为工作基础,充分分析了仪器数据格式,总结了传输数据流中的关键字(项目主要监测数值土壤碳通量的关键字为EXPFLUX),并基于.NET技术开发了实时传输数据解析软件,解决了研究过程中的国外仪器数据传输解析的问题。利用开源软件开发技术,实现了监测点位的分布展示、动态曲线图表生成、Excel数据导入导出等功能,为更好地进行土壤碳呼吸监测,提高科研工作效率,提供了保障。 展开更多
关键词 土壤碳呼吸 实时传输数据解析 开源软件开发技术 科研工作效率
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大洋硅藻席沉积与冰期旋回中的碳-氮循环 被引量:2
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作者 蔡雯沁 黄恩清 +1 位作者 柳双权 田军 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2024年第1期96-108,共13页
成席硅藻勃发与沉积埋藏过程链接了海洋有机碳生成-输出-埋藏以及大洋深部溶解无机碳的生成与储存的全过程,该过程及其对大洋碳-氮循环的潜在重大影响正引起学术界的关注。通过搜集整理一系列文献及数据,对成席硅藻在细胞层面的特殊功... 成席硅藻勃发与沉积埋藏过程链接了海洋有机碳生成-输出-埋藏以及大洋深部溶解无机碳的生成与储存的全过程,该过程及其对大洋碳-氮循环的潜在重大影响正引起学术界的关注。通过搜集整理一系列文献及数据,对成席硅藻在细胞层面的特殊功能、勃发机制以及硅藻席沉积物的时空分布特征进行了总结,尝试讨论硅藻席沉积对轨道时间尺度上全球碳-氮循环的潜在影响。由于成席硅藻具有一系列特点,包括在弱光条件下生存、利用大液泡来存储营养盐和调控浮力、与固氮蓝细菌共生、尿素循环等,导致成席硅藻在寡营养的层化水体中或者大洋锋面处容易获得生存竞争优势并发生勃发。根据沉积记录,在第四纪冰期,热带-亚热带大西洋以及热带西太平洋-东印度洋出现大规模的Ethmodiscus rex硅藻席勃发并向海洋内部输出大量有机碳。有机碳中的绝大部分都在水柱中发生降解,只有少部分保存到海底沉积物中。推测硅藻席勃发贡献了冰期深海内部“呼吸碳库”的增长以及大气二氧化碳浓度的降低。由于E.rex勃发加快了海洋上层营养盐的周转速率,因此也可能促进了冰期海洋氮储库的扩张。此外,氧同位素14/12期和4/2期间同时出现大洋无机碳碳同位素重值事件和热带-亚热带硅藻席勃发事件,二者之间可能存在机制上的关联。因此,成席硅藻是耦合大洋碳-氮循环的重要组成部分,进一步厘清地质历史时期硅藻席勃发规模及其在海洋元素循环中的作用,有助于解开冰期旋回尺度上的全球碳-氮循环之谜。 展开更多
关键词 成席硅藻 藻类勃发 次表层水 海洋生产力 大洋呼吸
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基于小尺度的高寒牧区碳排放估算——以甘南州合作市为例 被引量:1
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作者 王录仓 高静 《生态学报》 CAS CSCD 北大核心 2014年第21期6337-6345,共9页
碳排放是目前国内外研究的热点问题。纵观碳排放计算,关键涉及到两个环节:一是研究尺度的选择,二是评估参数(即碳排放/吸收系数)的确定。高寒牧区还必须充分考虑牲畜碳排放。以甘南州合作市为例,将研究尺度缩小到41个行政村,并采用最新... 碳排放是目前国内外研究的热点问题。纵观碳排放计算,关键涉及到两个环节:一是研究尺度的选择,二是评估参数(即碳排放/吸收系数)的确定。高寒牧区还必须充分考虑牲畜碳排放。以甘南州合作市为例,将研究尺度缩小到41个行政村,并采用最新的土地二调数据,对土地利用碳排放和碳汇、生活和牲畜碳排放进行了系统地测算。结果表明:(1)从土地利用的角度考察,合作市总碳排放表征为"碳亏"态势。总碳排放量为24374.82 t/a,其中土地利用碳排放量为4908.21 t/a,牲畜代谢碳排放量为3703.94 t/a,城乡居民生活碳排放量为15762.67 t/a。而碳汇量仅为1949.74 t/a,"碳亏"量为22425.08 t/a。(2)牲畜是高寒牧区呼吸碳排放的主体,其碳排量为3703.94t/a,其中牛是碳排放的主体,其碳排量占90%以上。(3)城乡居民生活碳排量为15762.67t/a,城镇明显高于农村,生存型碳排放强度高于发展型碳排放强度。(4)碳排放局分布势面与碳汇分布局势面基本呈反向分布态势,但总的碳排放格局取决于碳排放而非碳汇,空间分布表现为从城区—半农半牧区—纯牧区逐级递减的趋势。 展开更多
关键词 生存型排放 发展型排放 呼吸 合作市
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The contribution of root respiration of Pinus koraiensis seedlings to total soil respiration under elevated CO_2 concentrations 被引量:14
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作者 刘颖 韩士杰 +3 位作者 李雪峰 周玉梅 张军辉 贾夏 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期187-191,共5页
The impacts of elevated atmospheric CO2 concentrations (500 靘olmol-1and 700 靘olmol-1) on total soil respiration and the contribution of root respiration of Pinus koraiensis seedlings were investigated from May to Oc... The impacts of elevated atmospheric CO2 concentrations (500 靘olmol-1and 700 靘olmol-1) on total soil respiration and the contribution of root respiration of Pinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO2, the total soil respiration and roots respiration of Pinus koraiensis seedlings were measured by a LI-6400-09 soil CO2 flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil in-stantaneously to terminate the supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration. Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively. The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on June 16, the maximum of soil temperature at depth of 5 cm lagged behind that of air temperature, no differences in temperature between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 靘olm 2s-1, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8, respectively. 展开更多
关键词 Contribution of root respiration Elevated CO2 Pinus koraiensis Root-severed technique Soil respiration
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培菲康联合四联疗法根除幽门螺杆菌感染的效果观察 被引量:10
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作者 汤茵 梁健 +2 位作者 张国安 钟碧莹 龙靖华 《山东医药》 CAS 2014年第29期42-43,共2页
目的观察培菲康联合四联疗法根除幽门螺杆菌(Hp)感染的效果。方法选取Hp感染者100例,随机分为观察组、对照组各50例。对照组采用四联疗法(橼酸铋剂220 mg、左克20 mg,2次/d,阿莫西林1 000 mg和雷贝拉唑10 mg,2次/d)治疗1周;1周后给予奥... 目的观察培菲康联合四联疗法根除幽门螺杆菌(Hp)感染的效果。方法选取Hp感染者100例,随机分为观察组、对照组各50例。对照组采用四联疗法(橼酸铋剂220 mg、左克20 mg,2次/d,阿莫西林1 000 mg和雷贝拉唑10 mg,2次/d)治疗1周;1周后给予奥美拉唑20 mg,2次/d,治疗3周。观察组在对照组基础上联用培菲康(2片/次,3次/d)。两组均治疗4周。治疗结束后,采用13碳呼气试验检测Hp阳性率,ELISA法检测血清细胞毒素相关蛋白A(CagA)抗体阳性率。结果治疗4周后,观察组Hp、CagA抗体阳性率分别为12.0%、62.0%,对照组为44.0%、44.0%,两组比较P均<0.05。结论培菲康联合四联疗法可明显降低Hp阳性率,使CagA抗体趋向正常,值得临床推广应用。 展开更多
关键词 感染 幽门螺杆菌 培菲康 四联疗法 13碳呼吸试验 细胞毒素相关蛋白A抗体
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Soil Carbon Balance in a Native Temperate Grassland in the Xilin River Basin of Inner Mongolia 被引量:3
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作者 李凌浩 韩兴国 +8 位作者 王其兵 白文明 白永飞 闫志丹 陈全胜 张焱 杨晶 李鑫 宋世环 《Acta Botanica Sinica》 CSCD 2002年第6期740-742,共3页
Based on historical data and field investigation, some major fluxes and reserves of carbon were estimated, and a tentative analysis of the soil carbon balance was made in a native grassland community in the Xilin Rive... Based on historical data and field investigation, some major fluxes and reserves of carbon were estimated, and a tentative analysis of the soil carbon balance was made in a native grassland community in the Xilin River basin of Inner Mongolia. Major results were reported as follows: 1) Annual average carbon input from above-ground biomass production was 79.8 g C(.)m(-2.)a(-1), and from root biomass to 30 cm. depth averaged 311.9 g C(.)m(-2.)a(-1). The summed mean annual carbon input of shoot and root materials in the study site was approximately 391.7 g C(.)m(-2.)a(-1). 2) The annual amount of above-ground biomass consumed by insects averaged 14.7 g C(.)m(-2.)a(-1), and the carbon output by leaching or light-chemical oxidation was 3.2 g C(.)m(-2.)a(-1) The annual evolution rate of CO2 from net soil respiration averaged 346.9 g C(.)m(-2.)a(-1), and the summed mean annual output was approximately 364.8 g C(.)m(-2.)a(-1). 3) A mature, steady-state system could be assumed for the community for which growth and decay were approximately in balance, with a net carbon accumulation of about 26.9 g C(.)m(-2.)a(-1). Based on the soil organic carbon density of the field, the turnover Irate of soil carbon in 0 - 30 cm depth was calculated to be 6.2%, with a turnover time of 16 years. 展开更多
关键词 Leymus chinensis steppe carbon balance soil respiration turnover rate net primary productivity (NPP)
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不同植被类型下土壤胡敏酸降解特性
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作者 付东磊 刘梦云 +4 位作者 刘林 常庆瑞 左进香 罗勤 赵彤 《环境科学研究》 EI CAS CSSCI CSCD 北大核心 2014年第5期513-519,共7页
为了解不同植被类型下土壤HA(胡敏酸)降解菌的种类、分布状况及其中C的降解程度,选取退耕还林典型地带,于农田、油松、刺槐、沙棘、混交林0~10cm土样中分别提取HA,利用HA作为唯一C、N源筛选HA降解微生物.结果表明:相比农田土壤H... 为了解不同植被类型下土壤HA(胡敏酸)降解菌的种类、分布状况及其中C的降解程度,选取退耕还林典型地带,于农田、油松、刺槐、沙棘、混交林0~10cm土样中分别提取HA,利用HA作为唯一C、N源筛选HA降解微生物.结果表明:相比农田土壤HA,各林地土壤HA中甜(c)增加,”(N)有所减少;共分离获得5株HA降解菌,根据16srRNA序列鉴定,分别为Bacillus licheniformis、Rhizobiumn epotum、Microbacterium resistens、Stenotrophomonas maltophilia、Streptomyces azureus,相似度分别为99.65%、99.78%、98.71%、99.23%、99.78%.农田、刺槐、油松及混交林的降解菌优势种为Bacillus licheniformis,沙棘优势种为Streptomyces azureus,刺槐无Rhizobium nepotum分布,沙棘和混交林无Stenotrophomonas maltophilia分布;降解菌数量为沙棘〉刺槐〉农田〉油松〉混交林,混交林仅为沙棘的58.87%;混交林、油松、沙棘、刺槐降解菌的RC(呼吸量碳)分别较农田高出25.35%、11.28%、10.36%、7.11%,混交林与农田差异显著(P〈0.05).沙棘、刺槐、农田、油松降解菌MBC(微生物生物量碳)分别较混交林高出131.91%、68.48%、64.98%、54.47%,刺槐、农田、油松三者与沙棘及混交林差异显著(P〈0.05).沙棘土壤HA的TDR(总降解率)明显高于农田和混交林(P〈0.05).相关性分析表明,降解菌数量与MBC呈极显著正相关,与RC呈极显著负相关(P〈0.01).结果表明,植被类型影响了土壤HA降解菌的群落组成及其降解特性. 展开更多
关键词 植被类型 胡敏酸降解菌 呼吸 微生物生物量 总降解量
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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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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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Soil and Root Respiration Under Elevated CO_2 Concentrations During Seedling Growth of Pinus sylvestris var.sylvestriformis 被引量:6
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作者 LIU Ying HAN Shi-Jie +1 位作者 ZHOU Yu-Mei LI Xue-Feng 《Pedosphere》 SCIE CAS CSCD 2007年第5期660-665,共6页
The objectives of this study were to investigate the effect of higher CO2 concentrations (500 and 700 μmol mol^-1) in atmosphere on total soil respiration and the contribution of root respiration to total soil resp... The objectives of this study were to investigate the effect of higher CO2 concentrations (500 and 700 μmol mol^-1) in atmosphere on total soil respiration and the contribution of root respiration to total soil respiration during seedling growth of Pinus sylvestris vat. sylvestriformis. During the four growing seasons (May-October) from 1999 to 2003, the seedlings were exposed to elevated concentrations of CO2 in open-top chambers. The total soil respiration and contribution of root respiration were measured using an LI-6400-09 soil CO2 flux chamber on June 15 and October 8, 2003. To separate root respiration from total soil respiration, three PVC cylinders were inserted approximately 30 cm deep into the soil in each chamber. There were marked diurnal changes in air and soil temperatures on June 15. Both the total soil respiration and the soil respiration without roots showed a strong diurnal pattern, increasing from before sunrise to about 14:00 in the afternoon and then decreasing before the next sunrise. No increase in the mean total soil respiration and mean soil respiration with roots severed was observed under the elevated CO2 treatments on June 15, 2003, as compared to the open field and control chamber with ambient CO2. However, on October 8, 2003, the total soil respiration and soil respiration with roots severed in the open field were lower than those in the control and elevated CO2 chambers. The mean contribution of root respiration measured on June 15, 2003, ranged from 8.3% to 30.5% and on October 8, 2003, from 20.6% to 48.6%. 展开更多
关键词 contribution of root respiration elevated CO2 concentration total soil respiration
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带状滨水公共空间植物景观配置策略研究——以黄浦滨江公共空间世博段景观为例 被引量:6
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作者 顾芳 夏慧仕 朱晓君 《园林》 2021年第10期63-68,共6页
纵观世界发展史,城市发展大多因水而起,并且水环境对城市的空间塑造及景观形象呈现起重要作用。带状滨水公共空间作为城市滨水公共空间中的典型代表,对于城市滨水公共空间的建设发展研究有着极大的意义。以植物景观配置策略研究为切入点... 纵观世界发展史,城市发展大多因水而起,并且水环境对城市的空间塑造及景观形象呈现起重要作用。带状滨水公共空间作为城市滨水公共空间中的典型代表,对于城市滨水公共空间的建设发展研究有着极大的意义。以植物景观配置策略研究为切入点,结合当前绿化发展形式、相关要求以及带状滨水空间特征的分析,提出带状滨水公共空间植物景观配置三点策略,即低碳可呼吸式绿地建设、特色专类园景观建设、自然生境保护地建设,并应用在黄浦滨江公共空间世博段景观建设中,以期为带状滨水空间建设提供参考。 展开更多
关键词 带状滨水空间 呼吸式绿地 特色专类园
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Effect of canopy composition on soil CO_2 emission in a mixed sprucebeech forest at Solling,Central Germany 被引量:3
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作者 Seyed Mohammd Hojjati Norbert P.Lamersdorf 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第4期461-464,523,524,共6页
It was hypothesized that soil respiration can be affected by canopy composition. Hence, admixture of trees as a common forest management practice may cause significant change in the carbon cycling. This study was cond... It was hypothesized that soil respiration can be affected by canopy composition. Hence, admixture of trees as a common forest management practice may cause significant change in the carbon cycling. This study was conducted in a mixed spruce-beech stand at Solling forest in central Germany to investigate the effect of canopy composition on soil respiration. The canopy cover was classified in four major canopy classes (pure beech, pure spruce, mixed and gap), and the area under each canopy class was identified as a sub-plot. Soil respiration in each sub-plot (n=4) was measured monthly from Jun 2005 to July 2006. Results show significant difference in annual soil respiration between the beech (359g·m^-2·a^-1 C) and gap (211 g·m^-2·a^-1 C) sub-plots. The estimation of the total below-ground carbon allocation (TBCA) based on a model given by Raich and Nadelhoffer revealed considerably higher root CO2 production in the beech sub-plot (231 g·m^-2·a^-1 C) compare to the gap sub-plot (51 g·m^-2·a^-1 C ). The contribution of the root respiration to the total soil respiration was higher in the soil under the beech canopy (59%) compared with the soil in the gap (29%). The findings suggested that the condition under the beech canopy may cause more desirable micro-site for autotrophic respiration and consequently higher CO2 release into the atmosphere. 展开更多
关键词 canopy class soil respiration GAPS total belowground carbon allocation.
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Effects of Soil Fertility and Atmospheric CO_2 Enrichment on Leaf, Stem and Root Dark Respiration of Populus tremuloides 被引量:6
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作者 X. Z. WANG P. S. CURTIS +2 位作者 and C. S. VOGEL Columbia University, Palisades, New York 10964-8000 (USA) The Ohio State University, Columbus, Ohio 43210-1293 (USA) University of Michigan Biological Station, Pellston, Michigan 49769 (USA) 《Pedosphere》 SCIE CAS CSCD 2001年第3期199-208,共10页
An open-top chamber experiment was conducted at the University of Michigan Biological Station near Pellston, Michigan, USA, to study the effects of soil fertility and CO2 on leaf, stem and root dark respiration (Rd) o... An open-top chamber experiment was conducted at the University of Michigan Biological Station near Pellston, Michigan, USA, to study the effects of soil fertility and CO2 on leaf, stem and root dark respiration (Rd) of Populus tremuloides. Overall, area-based day-time leaf Rd (Rda) was significantly greater at elevated than at ambient CO2 in high-fertility soil, but not in low-fertility soil. Mass-based leaf Rd (Rdm) was overall greater for high- than for low-fertility soil grown trees at elected, but not at ambient CO2. Nighttime leaf Rd. and Rdm were unthected by soil fertility or CO2, nor was stem Rda, which ranged from 1.0 to 1.4 μmol m-2 s-1 in the spring and 3.5 to 4.5 μmol m-2 s-1 in the summer. Root Rda. was significantly higher in high- than in low-fertility soil, but was unaffected by CO2. Since biomass production of P. tremuloides will be significantly greater at elevated CO2 while specific Rd will either increase or remain unchanged, we predict that carbon loss to the atmosphere through respiration from this ecologically important species would increase at higher CO2. Soil fertility would also interact with elevated CO2 in affecting the carbon flow in the plant-soil-air system. 展开更多
关键词 leaf dark respiration Populus tremuloides root respiration soil fertility stem respiration
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Trends in carbon sink along the Belt and Road in the future under high emission scenario
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作者 Jing Peng Li Dan +1 位作者 Xiba Tang Fuqiang Yang 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第3期46-50,共5页
Over the past three decades,the drawdown of atmospheric CO_(2) in vegetation and soil has fueled net ecosystem production(NEP).Here,a global land-surface model(CABLE)is used to estimate the trend in NEP and its respon... Over the past three decades,the drawdown of atmospheric CO_(2) in vegetation and soil has fueled net ecosystem production(NEP).Here,a global land-surface model(CABLE)is used to estimate the trend in NEP and its response to atmospheric CO_(2),climate change,biological nitrogen(N)fixation,and N deposition under future conditions from 2031 to 2100 in the Belt and Road region.The trend of NEP simulated by CABLE decreases from 0.015 Pg carbon(C)yr^(-2) under present conditions(1936–2005)to−0.023 Pg C yr^(-2) under future conditions.In contrast,the trend in NEP of the CMIP6 ensemble changes from 0.014 Pg C yr^(-2) under present conditions to−0.009 Pg C yr^(-2) under future conditions.This suggests that the trend in the C sink for the Belt and Road region will likely decline in the future.The significant difference in the NEP trend between present and future conditions is mainly caused by the difference in the impact of climate change on NEP.Considering the responses of soil respiration(RH)or net primary production(NPP)to surface air temperature,the trend in surface air temperature changes from 0.01℃ yr^(-1) under present conditions to 0.05℃ yr^(-1) under future conditions.CABLE simulates a greater response of RH to surface temperature than that of NPP under future conditions,which causes a decreasing trend in NEP.In addition,the greater decreasing trend in NEP under future conditions indicates that the C-climate-N interaction at the regional scale should be considered.It is important to estimate the direction and magnitude of C sinks under the C neutrality target. 展开更多
关键词 Carbon sink Soil respiration Climate change CO_(2)concentration Biological nitrogen fixation Atmospheric nitrogen deposition
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我国诊断胃病有新仪器
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《健康博览》 2001年第5期18-18,共1页
关键词 诊断 胃病 十三尿素呼吸质谱仪
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碳14呼吸试验阳性患者与家庭成员同期抗幽门螺旋杆菌治疗必要性研究
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作者 万娟 《中文科技期刊数据库(全文版)医药卫生》 2022年第3期8-10,共3页
研究碳14呼吸试验阳性患者与家庭成员同期抗幽门螺旋杆菌治疗的必要性。方法:随机数字表法将上海市浦东新区三林康德社区卫生服务中心于2021年筛查的62例碳14呼吸试验阳性患者分为同期组38例和非同期组24例,对比两组受试患者与家庭成员... 研究碳14呼吸试验阳性患者与家庭成员同期抗幽门螺旋杆菌治疗的必要性。方法:随机数字表法将上海市浦东新区三林康德社区卫生服务中心于2021年筛查的62例碳14呼吸试验阳性患者分为同期组38例和非同期组24例,对比两组受试患者与家庭成员是否同期进行抗幽门螺旋杆菌诊治后幽门螺旋杆菌的根除情况。结果:同期组幽门螺旋杆菌转阴率明显高于非同期组,非同期组复阳率明显高于同期组,同期组与非同期组组间对比差异统计学意义存在(P<0.05)。结论:对碳14呼吸试验阳性患者与家庭成员同期抗幽门螺旋杆菌治疗及其必要,可以有效治疗患者的幽门螺旋杆菌,提高患者治疗率,减少患者复阳率发生,对预防和治疗幽门螺旋杆菌感染有积极意义。 展开更多
关键词 14呼吸试验 家庭成员同期治疗 抗幽门螺旋杆菌治疗
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BAG3-Related Myofibrillar Myopathy Presenting as Hypercapnia:A Case Report and Literature Review
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作者 Yan Xu Shixuan Liu +7 位作者 Wenbing Xu Jinmei Luo Jingwen Niu Zhi Liu Jinming Gao Jinglan Wang Yi Dai Mengzhao Wang 《Chinese Medical Sciences Journal》 CAS CSCD 2021年第4期265-278,共14页
Objective BAG3-related myopathy is a rare condition so far reported in twenty patients worldwide.The purpose of this study was to draw attention to this rare disease and to the fact that BAG3-related myopathy should b... Objective BAG3-related myopathy is a rare condition so far reported in twenty patients worldwide.The purpose of this study was to draw attention to this rare disease and to the fact that BAG3-related myopathy should be considered as a rare differential diagnosis of hypercapnia.Methods We report a sporadic case of a 14-year-old Chinese girl with a de novo p.Pro209 Leu mutation in BAG3 and reviewed the literatures for reported cases related to this mutation.Results We described a 14-year-old Chinese girl who presented with gradually appearing symptoms of hypercapnia that required assisted ventilation.The muscle biopsy and the blood whole-exome sequencing results confirmed the diagnosis of myofibrillar myopathy with a de novo p.Pro209 Leu mutation in BAG3.Totally twentyone patients from twenty families with a confirmed diagnosis of BAG3-related myopathy were reported to date,including this patient and literature review.The male to female ratio was 11:10 and most showed initial symptoms in the first decade of life.Most patients presented toe/clumsy walking or running as the onset symptom,followed by muscle weakness or atrophy.Creatine kinase levels were elevated in fourteen patients and were normal in three.Eighteen patients developed respiratory insufficiency during the disease course and thirteen(one could not tolerate non-invasive assisted ventilation)required non-invasive assisted ventilation for treatment.Except for one not reported,heart involvement was found in seventeen patients during the disease course and seven underwent heart transplantation.Z-disk streaming and aggregation could be observed in most of the patients’muscle histology.In the long-term follow-up,five patients died of cardiac or respiratory failure.Conclusion BAG3-associated myopathy is a rare type of myofibrillar myopathy.It should be considered as a rare differential diagnosis of hypercapnia. 展开更多
关键词 myofibrillar myopathy BAG3 respiratory insufficiency HYPERCAPNIA
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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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Contemporary Medical Qigong: Introduction to Holo-Cosmic Qigong
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作者 Abraham Shue Yan Poon 《Cultural and Religious Studies》 2017年第10期591-598,共8页
The word of “qi” means the air. That is the breathing air exercise of changing air for the body. The oxygen is breathed in and the carbon dioxide is going out. It is including lute style breathing, lower part breat... The word of “qi” means the air. That is the breathing air exercise of changing air for the body. The oxygen is breathed in and the carbon dioxide is going out. It is including lute style breathing, lower part breathing, skin breathing, acupuncture points breathing, baby breathing, etc. Also, there is breathing in long and out, short, one in and three out, counting number, etc. There are so many different kinds method and the effect or result will be totally different. So, we call it helping-life at ancient. It had a completed human medical theory for fundamental to make the life freedom and living colorful. 展开更多
关键词 QI Holo-Cosmic Qigong 20 characters
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贡嘎山峨眉冷杉成熟林碳利用效率季节动态及其影响因子 被引量:3
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作者 舒树淼 朱万泽 +2 位作者 冉飞 孙守琴 张元媛 《植物生态学报》 CAS CSCD 北大核心 2020年第11期1127-1137,共11页
碳利用效率(CUE)是植被生态系统的一个重要功能参数,反映了植被生态系统的固碳能力,适用于分析不同时间段内器官、个体和群落等不同层次的碳收支趋势,因而有助于对陆地生态系统碳功能的确定与预测,引起了广泛关注。该研究采用生物计量法... 碳利用效率(CUE)是植被生态系统的一个重要功能参数,反映了植被生态系统的固碳能力,适用于分析不同时间段内器官、个体和群落等不同层次的碳收支趋势,因而有助于对陆地生态系统碳功能的确定与预测,引起了广泛关注。该研究采用生物计量法,测定和计算了川西贡嘎山东坡峨眉冷杉(Abiesfabri)成熟林树木不同器官的呼吸与净生产力动态,分析了乔木层及其各器官CUE动态及主要影响因子,并估算了乔木层不同径级树木CUE。主要结果:(1)乔木层各器官月呼吸速率与温度呈正相关关系,以细根月呼吸速率为最大;不同径级树木年呼吸量无显著差异,以小径级树木树干的年呼吸量为最小。(2)乔木层细根和树干月净初级生产力(NPP)均随温度增加而增加,以细根月NPP为最大。小径级树木年NPP最大,其针叶年NPP也显著高于中径级和大径级树木。(3)林分乔木层及其各器官CUE大多集中在0.30–0.60之间,其中细根、树干CUE具有相似的月变化动态,均随温度的升高而上升。不同径级树木CUE及树干和针叶CUE均随树木个体的增大而明显下降。(4)气温和土壤温度与乔木层树干和细根CUE呈正相关关系,而降水量与针叶CUE呈负相关关系。细根CUE与树干CUE呈正相关关系,与针叶CUE呈负相关关系。峨眉冷杉成熟林乔木层CUE主要取决于树干和细根CUE。该研究证实了川西亚高山暗针叶成熟林仍具有较强的碳汇功能,在区域碳储存和森林生态系统碳循环中发挥着极其重要的作用。 展开更多
关键词 利用效率 净初级生产力 呼吸消耗 峨眉冷杉成熟林 贡嘎山
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