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FACTORS AFFECTING SOIL RESPIRATION IN REFERENCE WITH TEMPERATURE'S ROLE IN THE GLOBAL SCALE 被引量:4
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作者 方精云 刘绍辉 赵坤 《Chinese Geographical Science》 SCIE CSCD 1998年第3期55-64,共0页
Soil respiration is CO 2 evolution process from soil to atmosphere, mainly produced by soil micro organism and plant roots. It is affected not only by biological factors (vegetation, micro organism, etc.) and envir... Soil respiration is CO 2 evolution process from soil to atmosphere, mainly produced by soil micro organism and plant roots. It is affected not only by biological factors (vegetation, micro organism, etc.) and environmental factors (temperature, moisture, pH, etc.), but also more and more strongly by man made factors. Based on literature survey, main factors affecting soil respiration were reviewed. The relationships of soil respiration to latitude and to mean annual temperature were analyzed by using the data measured from forest vegetation in the world. As a result, soil respiration rate decreased exponentially with an increase of latitude, and increased with increasing temperature. Following the relationship between soil respiration and temperature, Q 10 value (law of Van Hoff) was obtained as 1.57 in the global scale. 展开更多
关键词 effect FACTORS q 10 value LATITUDE SOIL RESPIRATION temperature
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Temperature dependence of nitrogen mineralization and microbial status in O_H horizon of a temperate forest ecosystem 被引量:2
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作者 Ali Bagherzadeh Rainer Brumme Friedrich Beese 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期37-43,共7页
It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nit... It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nitrogen in humus, and consequently development in OH horizon (humus horizon). To quantify the effect of temperature on biochemical processes controlling the rate of OH layer development three adjacent forest floors under beech, Norway spruce and mixed species stands were investigated at Soiling forest, Germany by an incubation experiment of OH layer for three months. Comparing the fitted curves for temperature sensitivity of OH layers in relation to net N mineralization revealed positive correlation across all sites. For the whole data set of all stands, a Q10 (temperature sensitivity index) value of 2.35-2.44 dependent on the measured units was found to be adequate for describing the temperature dependency of net N mineralization at experimental site. Species-specific differences of substrate quality did not result in changes in biochemical properties of OH horizon of the forest floors. Temperature elevation increased net N mineralization without significant changes in microbial status in the range of I to 15℃. A low Cmic /Corg (microbial carbon/organic carbon) ratio at 20℃ indicated that the resource availability for decomposers has been restricted as reflected in significant decrease of microbial biomass. 展开更多
关键词 BEECH SPRUCE nitrogen mineralization forest floor temperature temperature sensitivity index (q10)
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Temperature dependence of carbon mineralization and nitrous oxide emission in a temperate forest ecosystem
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作者 Ali Bagherzadeh Rainer Brumme Friedrich Beese 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第2期107-112,共6页
The measurement of CO2 and N2O effiux from forest soils is of great importance in evaluating the role of forests as sequestering agents of atmospheric CO2 and nitrogen. To quantify the effect of site on temperature de... The measurement of CO2 and N2O effiux from forest soils is of great importance in evaluating the role of forests as sequestering agents of atmospheric CO2 and nitrogen. To quantify the effect of site on temperature dependence of net C-mineralization and N2O-N emissions, three adjacent forest floors under beech, Norway spruce and mixed species stands were investigated at Soiling forest, Germany, by an incubation experiment for three months. The investigated net C-mineralization and N2O-N emissions from all forest floors exhibited an exponential increase with respect to temperature elevation. The temperature coefficient function (Q10 value), was fitted to flux rates to describe the temperature sensitivity of forest floors on temperature in the range of 1-20℃. Comparing the fitted curves for temperature sensitivity of the forest floors in relation to net carbon mineralization and nitrous oxide emission rates revealed a strong positive correlation across all sites. For the whole data set of all stands, a Q10 value of 1.73-2.10 for net C-mineralization and 2.81-3.58 for N2O-N emissions per measured unit was found to describe the temperature dependency of net C-mineralization and N20-N efflux at experimental site. The absence of clear differences between beech and spruce in mono and mixed species cultures on temperature dependencies of net C-mineralization and N2O-N emission rates indicated that the flux rates were not affected by species-specific differences of litter quality. 展开更多
关键词 BEECH SPRUCE net C-mineralization nitrous oxide emission temperature temperature sensitivity index (q10)
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高Q微波介质谐振器材料D_5的研究 被引量:1
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作者 周水杉 李秀清 《电子元件与材料》 CAS CSCD 1997年第5期20-23,共4页
研制出新型D5微波介质谐振器材料。该材料为ABO3型钙钛矿化合物。化学组成式为Ba(Zrx,Zny,Taz)On(式中x+y+z=1,n为任意)。该材料具有稳定的工艺特性和良好的微波性能。10GHz下,无载Q值Q0=... 研制出新型D5微波介质谐振器材料。该材料为ABO3型钙钛矿化合物。化学组成式为Ba(Zrx,Zny,Taz)On(式中x+y+z=1,n为任意)。该材料具有稳定的工艺特性和良好的微波性能。10GHz下,无载Q值Q0=9000,相对介电常数εr=30,谐振频率温度系数τf(10-6℃-1)在0附近可调。该材料的出现为X波段乃至Ku波段微波介质谐振器的应用提供了一种良好的可供选择的材料。 展开更多
关键词 微波介质材料 介质谐振器 振荡器
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10MW高温气冷堆温度系数的测量和评价
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作者 胡守印 王瑞偏 +1 位作者 经荥清 梁锡华 《核动力工程》 EI CAS CSCD 北大核心 2004年第4期301-304,共4页
在没有辅助热源的情况下,采用主氦风机循环和不大于500kW的核功率的联合加热方式加热堆芯并测量10MW高温气冷堆的温度系数,用周期法测得石墨反射层平均温度从45.48℃到236.93℃过程中引起的反应性变化。同时,通过物理计算对测量结果进... 在没有辅助热源的情况下,采用主氦风机循环和不大于500kW的核功率的联合加热方式加热堆芯并测量10MW高温气冷堆的温度系数,用周期法测得石墨反射层平均温度从45.48℃到236.93℃过程中引起的反应性变化。同时,通过物理计算对测量结果进行评估,如果扣除氙毒和温度分布的影响,测量值和计算值是符合的。 展开更多
关键词 高温气冷堆 温度系数 反应性变化
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Does a General Temperature-Dependent Q10 Model of Soil Respiration Exist at Biome and Global Scale? 被引量:37
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作者 Hua CHEN Han-Qin TIAN 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2005年第11期1288-1302,共15页
Soil respiration (SR) is commonly modeled by a Q10 (an indicator of temperature sensitivity) function in ecosystem models. Q10 is usually treated as a constant of 2 in these models, although Q10 value of SR often ... Soil respiration (SR) is commonly modeled by a Q10 (an indicator of temperature sensitivity) function in ecosystem models. Q10 is usually treated as a constant of 2 in these models, although Q10 value of SR often decreases with increasing temperatures. It remains unclear whether a general temperature- dependent Q10 model of SR exists at biome and global scale. In this paper, we have compiled the long-term Q10 data of 38 SR studies ranging from the Boreal, Temperate, to Tropical/Sublropical biome on four continents. Our analysis indicated that the general temperature-dependent biome Q10 models of SR existed, especially in the Boreal and Temperate biomes. A single-exponential model was better than a simple linear model in fitting the average Q10 values at the biome scale. Average soil temperature is a better predictor of Q10 value than average air temperature in these models, especially in the Boreal biome. Soil temperature alone could explain about 50% of the Q10 variations in both the Boreal and Temperate biome single-exponential Q10 model. Q10 value of SR decreased with increasing soil temperature but at quite different rates among the three biome Q10 models. The k values (Q10 decay rate constants) were 0.09, 0.07, and 0.02/℃ in the Boreal, Temperate, and Tropical/Subtropical biome, respectively, suggesting that Q10 value is the most sensitive to soil temperature change in the Boreal biome, the second in the Temperate biome, and the least sensitive in the Tropical/ Subtropical biome. This also indirectly confirms that acclimation of SR in many soil warming experiments probably occurs. The k value in the "global" single-exponential Q10 model which combined both the Boreal and Temperate biome data set was 0.08/℃. However, the global general temperature-dependent Q10 model developed using the data sets of the three biomes is not adequate for predicting Q10 values of SR globally. The existence of the general temperature-dependent Q10 models of SR in the Boreal and Temperate biome has important implications for modeling SR, especially in the Boreal biome. More detail model runs are needed to exactly evaluate the impact of using a fixed Q10 vs a temperature-dependent Q10 on SR estimate in ecosystem models (e.g., TEM, Biome-BGC, and PnET). 展开更多
关键词 air temperature biome q10 model global q10 model simple linear model single-exponentialmodel soil respiration (SR) soil temperature temperature sensitivity (q10).
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Eff ects of environmental factors on the temporal and spatial variations in branch and leaf CO_(2)effl ux of Larix gmelinii var.principis-rupprechtii Mayr
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作者 Longjie Li Xiangzhen Wang Zhongkui Jia 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1007-1019,共13页
The CO_(2)effl ux of branches and leaves plays an important role in ecosystem carbon balance.Using a carbon fl ux system,the effl ux of Larix gmelinii var.principisrupprechtii(Dahurian larch)was investigated in 27 yea... The CO_(2)effl ux of branches and leaves plays an important role in ecosystem carbon balance.Using a carbon fl ux system,the effl ux of Larix gmelinii var.principisrupprechtii(Dahurian larch)was investigated in 27 years(immature),31 years(near-mature),and 47 years(mature)stands at diurnal,seasonal,and spatial scales(direction and height)as well as its connection with environmental factors from May to October 2020.Diurnal variation in effl ux was a single peak,and the maximum occurring between 14:00 and 16:00.Seasonal variation also exhibited a single peak,with the maximum in late July and the minimum in early October.From May to September,effl ux on the south side was the largest among the three stands,and mean values on the south side of 27 year-old,31 year-old,and 47 year-old trees were 0.50,0.97 and 1.05μmol·m^(–2)·s^(–1),respectively.The minimum occurred on the north side.Except for the maximum in July and September in the 27 year-old stand in the middle of the canopy,the maximum effl ux in the upper canopy,and the means in the 27 year-old,31 year-old,and 47 year-old stands were 0.49,0.96 and 1.04μmol·m^(-2)·s^(-1),respectively;the minimum occurred in the lower canopy.Temperatures and relative humidity infl uenced seasonal variations in effl ux.Seasonal variation in temperature sensitivity coeffi cient(Q 10)was opposite that of temperature,increasing with decreasing temperature.At the spatial scale,maximum Q 10 occurred in the mid canopy.With the effl ux and temperature data in diff erent locations,it is possible to better estimate effl ux variations in each stand. 展开更多
关键词 CO_(2)effl ux temperature sensitivity coeffi cient(q 10) Temporal and spatial variations Environmental factors
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典型温带草原群落土壤呼吸温度敏感性与土壤水分的关系 被引量:164
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作者 陈全胜 李凌浩 +10 位作者 韩兴国 阎志丹 王艳芬 张焱 熊小刚 陈世苹 张丽霞 高英志 唐芳 杨晶 董云社 《生态学报》 CAS CSCD 北大核心 2004年第4期831-836,共6页
工业革命以来 ,人类活动所导致的 CO2 等温室气体的浓度在大气中持续上升 ,全球表面温度因此不断升高。在全球温暖化的背景下 ,土壤呼吸与温室效应之间正反馈关系势必影响到未来陆地生态系统功能与全球变化的趋势 ,所以 ,关于土壤呼吸... 工业革命以来 ,人类活动所导致的 CO2 等温室气体的浓度在大气中持续上升 ,全球表面温度因此不断升高。在全球温暖化的背景下 ,土壤呼吸与温室效应之间正反馈关系势必影响到未来陆地生态系统功能与全球变化的趋势 ,所以 ,关于土壤呼吸对温度变化响应的研究备受瞩目。土壤呼吸对温度依赖性的研究已经有许多报道 ,其关系可以用简单的指数方程表示。但是 ,土壤水分条件对于土壤呼吸温度敏感性 (用 Q1 0 表示 )的影响却研究得较少。采用碱液吸收法对内蒙古典型温带草原 11个不同水分状况群落的土壤呼吸进行了测定 ,并分析了土壤呼吸的温度敏感性。结果显示土壤呼吸的温度敏感性存在一定程度的空间变异 ,各群落 Q1 0 值平均为 1.6 5 ,变异系数为 6 .94 %。其中 ,春小麦群落的 Q1 0 值最高 (1.84 ) ,其次是湿生杂类草群落 (Q1 0 =1.78) ,而 Q1 0 最低的是冷蒿 (Armesia frigida) -星毛萎陵菜 (Potentilla acaulis)群落 (1.4 7)。用 Spearm an秩相关分析法对表层土壤(0~ 2 0 cm )水分与 Q1 0 值之间的关系进行了分析 ,结果表明各群落 Q1 0 值与生长季土壤平均水分含量呈显著的正相关关系 (R=0 .6 4 5 4 5 ,p=0 .0 32 ) ,说明水分状况对土壤呼吸的温度敏感性有一定程度的影响。由此推断 ,在中国温带草原地区 ,? 展开更多
关键词 土壤CO2排放 土壤含水量 Spearman秩相关系数 q10
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Soil Organic Carbon Mineralization as Affected by Cyclical Temperature Fluctuations in a Karst Region of Southwestern China 被引量:12
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作者 CI En Mahdi M.AL-KAISI +2 位作者 WANG Liange DING Changhuan XIE Deti 《Pedosphere》 SCIE CAS CSCD 2015年第4期512-523,共12页
The diurnal fluctuation in soil temperature may influence soil organic carbon (SOC) mineralization, but there is no consensus on SOC mineralization response to the cyclical fluctuation in soil temperature. A 56-d in... The diurnal fluctuation in soil temperature may influence soil organic carbon (SOC) mineralization, but there is no consensus on SOC mineralization response to the cyclical fluctuation in soil temperature. A 56-d incubation experiment was conducted to investigate the effects of constant and variable temperatures on SOC mineralization. Three soils were collected from the karst region in western Guizhou Province, southwestern China, including a limestone soil under forest, a limestone soil under crops and a yellow soil under crops. According to the World Reference Base (WRB) classification, the two limestone soils were classified as Haplic Luvisols and the yellow soil as a Dystric Luvisol. These soils were incubated at three constant temperatures (15, 20 and 25 ℃) and cyclically fluctuating temperatures (diurnal cycle between 15 and 25 ℃). The results showed that the 56-d cumulative SOC mineralized (C56) at the fluctuating temperatures was between those at constant 15 and 25 ℃, suggesting that the cumulative SOC mineralization was restricted by temperature range. The SOC mineralization responses to the fluctuating temperatures were different among the three soils, especially in contrast to those at constant 20 ~C. Compared with constant 20 ℃, significant (P 〈 0.05) decreases and increases in C56 value were found in the limestone soil under forest and yellow soil under crops at the fluctuating temperatures, respectively. At the fluctuating temperatures, the forest soil with lower temperature coefficient Q10 (the relative change in SOC mineralization rate as a result of increasing the temperature by 10 ℃) had a significantly (P 〈 0.05) lower SOC mineralization intensity than the two cropland soils. These indicated that differences in temperature pattern (constant or fluctuating) could significantly influence SOC mineralization, and SOC mineralization responses to the fluctuating temperatures might be affected by soil characteristics. Moreover, the warmer temperatures might improve the ability of soil microbes to decompose the recalcitrant SOC fraction, and cyclical fluctuations in temperature could influence SOC mineralization through changing the labile SOC pool size and the mineralization rate of the recalcitrant SOC in soils. 展开更多
关键词 labile C limestone soil recalcitrant C temperature coefficient (q10) yellow soil
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华西雨屏区常绿阔叶林土壤氮矿化对温度和湿度变化的响应 被引量:13
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作者 唐海龙 王景燕 +2 位作者 黄帅 龚伟 周于波 《甘肃农业大学学报》 CAS CSCD 北大核心 2019年第2期124-131,共8页
【目的】研究氮矿化对土壤湿度和温度的响应,为区域土壤供氮潜力评价和预测区域性水热变化对土壤氮素矿化影响提供参考.【方法】采用实验室培养法,研究不同温度(5、15、25、35℃)和水分含量(20%、40%、60%和80%田间持水量(FWC))对华西... 【目的】研究氮矿化对土壤湿度和温度的响应,为区域土壤供氮潜力评价和预测区域性水热变化对土壤氮素矿化影响提供参考.【方法】采用实验室培养法,研究不同温度(5、15、25、35℃)和水分含量(20%、40%、60%和80%田间持水量(FWC))对华西雨屏区常绿阔叶林表层(0~20 cm)土壤氮素矿化的影响.【结果】温度和水分含量对常绿阔叶林土壤氮矿化影响显著(P<0.05);相同水分条件下,土壤净氨化速率、净硝化速率和氮净矿化速率均随温度的升高呈先升高后降低的趋势,在25℃时达到最大值;相同温度条件下,土壤净氨化速率、净硝化速率和氮净矿化速率均随水分含量的升高呈先升高后降低的趋势,在60%FWC时达到最大值;在25℃+60%FWC处理下土壤净氨化速率、净硝化速率和氮净矿化速率速率最高,相反,在5℃+20%FWC处理下最低;能获得最大氮净矿化速率的土壤温度和水分含量分别为25.8℃和57.4%FWC;土壤氮净矿化产生的无机氮中铵态氮占54.1%~61.7%;土壤氮矿化Q_(10)值在5~35℃内随温度的升高而降低,氮净矿化在5~15℃内对温度敏感性最高.【结论】适宜的土壤水分含量和温度是促进常绿阔叶林土壤氮矿化的关键,研究区气温变暖在一定程度上能促进氮矿化和提高土壤供氮潜力,而研究区多雨则增加了土壤氮淋失的风险. 展开更多
关键词 氮矿化 q10 温度和湿度 常绿阔叶林 华西雨屏区
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(Ba_(0.5)Pb_(0.5))O·La_2O_3·4TiO_2-(Zr_(0.8)Sn_(0.2))TiO_4复合系统的微波介电性能 被引量:3
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作者 徐江峰 倪尔瑚 +1 位作者 朱永花 王艳华 《硅酸盐学报》 EI CAS CSCD 北大核心 1999年第3期287-292,共6页
研究了(Ba0.5Pb0.5)O·La2O3·4TiO2-(Zr0.8Sn0.2)TiO4复合系统的微波介电性能、烧结性能和微观结构,发现复合系统由(BaPb)6-xLa8+2x/3Ti18O54,La4Ti... 研究了(Ba0.5Pb0.5)O·La2O3·4TiO2-(Zr0.8Sn0.2)TiO4复合系统的微波介电性能、烧结性能和微观结构,发现复合系统由(BaPb)6-xLa8+2x/3Ti18O54,La4Ti9O24和(Zr0.8Sn0.2)TiO43相组成,而(Ba0.5Pb0.5)O·La2O3·4TiO2除了(BaPb)6-xLa8+2x/3Ti18O54和La4Ti9O24外还有一未知相,(Zr0.8Sn0.2)TiO4是单一晶相.复合后,系统的烧结温度比原两系统降低了.复合系统的微波介电常数、频率温度系数、Q因子主要与其中的相组成有关.结果表明未知相很可能具有高介电常数、低频率温度系数、高Q因子.对微波介电性能的测量值和由复合关系导出的计算值进行了比较. 展开更多
关键词 微波陶瓷 介电常数 烧结 性能 陶瓷
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青岛三种海产红藻的光合和呼吸特性的初步研究 被引量:4
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作者 吴超元 张京浦 +2 位作者 温宗存 彭作圣 刘海航 《海洋与湖沼》 CAS CSCD 北大核心 1996年第2期207-212,共6页
于1981年在青岛近海采集真江食、石花莱和角叉菜样品,用氧电极法测定它们在不同生长季节和发育阶段的光合和呼吸速率,并研究不同温度对其光合和呼吸速率的影响,同时计算出它们的呼吸温度系数。结果表明,3种红藻具有典型的潮间带海... 于1981年在青岛近海采集真江食、石花莱和角叉菜样品,用氧电极法测定它们在不同生长季节和发育阶段的光合和呼吸速率,并研究不同温度对其光合和呼吸速率的影响,同时计算出它们的呼吸温度系数。结果表明,3种红藻具有典型的潮间带海藻的光合特性,即高光饱和点为600—1000μE/(m2·s),较高的光补偿点为12-40μE/(m2·s)和较高的光合适温≥25℃。温度对3种红藻的光合和呼吸的影响均很明显,在5,15,25℃下测试,它们的最高光合和呼吸速率都出现在25℃。3种红藻的呼吸温度系数(Q10),在5-15℃较高,为1.4-5.5在15-25℃较低,为1.1-2.7。说明它们在低温下的呼吸受温度变动影响较大。经计算3种红藻在适宜生长温度下的净光合速率:角又菜和真江蒿在15℃分别为4.90O2mg/(g·h)和8.14O2mg/(g·h);石花菜在25℃为11.87O2mg/(g·h),在3种红藻中最高。这说明,石花菜的光合效率并不象人们预料的那样低,其秋季幼体在25℃,1000μE/(m2·s)光强下,净光合速率达到19.19O2mg/(g·h)。看来在自然界石花菜生长缓慢主要是由于生境中低光照强度和较低水温所致。 展开更多
关键词 真红蓠 石花菜 红藻 角叉菜 光合速率 呼吸速率
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干旱区盐湖沿岸土壤呼吸特征及其影响因素 被引量:5
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作者 李典鹏 姚美思 +2 位作者 孙涛 刘隋赟昊 贾宏涛 《干旱区地理》 CSCD 北大核心 2020年第3期761-769,共9页
明确不同生态系统土壤碳排放规律及其影响因素对准确评估全球碳循环具有重要意义。为揭示干旱区典型盐湖沿岸土壤呼吸(Rs)、土壤呼吸温度敏感系数(Q10)变化特征及其影响因素,以新疆干旱区达坂城盐湖和巴里坤湖沿岸土壤为研究对象,在2015... 明确不同生态系统土壤碳排放规律及其影响因素对准确评估全球碳循环具有重要意义。为揭示干旱区典型盐湖沿岸土壤呼吸(Rs)、土壤呼吸温度敏感系数(Q10)变化特征及其影响因素,以新疆干旱区达坂城盐湖和巴里坤湖沿岸土壤为研究对象,在2015-2016年5~10月利用LI-8100土壤碳通量自动测量系统对盐湖沿岸土壤呼吸速率进行测定,分析了土壤呼吸季节性变化特征及其影响因子。结果表明,干旱区盐湖土壤呼吸变幅较大(0.07~11.59μmol·m-2·s-1),平均值为2.45μmol·m-2·s-1,7月土壤呼吸速率最高为4.69μmol·m-2·s-1,10月最低(1.01μmol·m-2·s-1);土壤CO2累积排放量为9.30 g·m-2·d-1,7月累积排放量最大为17.82 g·m-2·d-1。Q10呈"降低-增加-降低"趋势,6月最低(2.25)9月最高(3.52),平均值为2.79。干旱区盐湖沿岸土壤呼吸受土壤有机碳(SOC)、5 cm土壤温度(ST5)、土壤含水量(SM)和土壤盐分(Salt)的共同影响,单因素模型模拟可解释土壤呼吸速率变化的41.7%~75.7%(R2=0.417~0.757,P<0.05),多因子综合模型拟合结果最佳Rs=0.001×SOC+0.039×SM-0.534×Salt-0.116×ST5+5.06(R2=0.804,P=0.05),且均表明盐分是影响干旱区盐湖沿岸土壤呼吸速率的主要因子。因此,在考虑陆地生态系统碳收支和碳循环时不能忽略干旱区盐湖沿岸土壤碳过程,以及盐分对盐湖生态系统碳排放的影响。 展开更多
关键词 碳排放 土壤盐分 达坂城盐湖 巴里坤湖 土壤温度敏感系数
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胃安康口服液的稳定性研究
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作者 赵汝海 王泽芳 +3 位作者 周军 杜劲 王文 石静 《解放军药学学报》 CAS 1999年第6期4-6,共3页
目的 :建立预测胃安康口服液有效期的方法。方法 :根据化学动力学原理 ,以黄芪甲甙为指标 ,薄层扫描法定量 ,采用Q10 法和经典恒温法 ,分别对胃安康口服液稳定性进行了研究。结果 :本品室温下贮存期分别为 5 69.6d和 5 68.5d。结论 :两... 目的 :建立预测胃安康口服液有效期的方法。方法 :根据化学动力学原理 ,以黄芪甲甙为指标 ,薄层扫描法定量 ,采用Q10 法和经典恒温法 ,分别对胃安康口服液稳定性进行了研究。结果 :本品室温下贮存期分别为 5 69.6d和 5 68.5d。结论 :两种方法均可预测本品的有效期 ,Q10 法更为简便、省时 。 展开更多
关键词 胃安康口服液 稳定性 黄芪甲甙 q10 标准曲线 经典恒温法
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南阳盆地农田裸地土壤呼吸温度敏感性变化特征分析 被引量:2
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作者 翟智峰 赵文凯 +1 位作者 王耀庆 赵志敏 《南阳师范学院学报》 CAS 2017年第9期28-32,共5页
南阳盆地处于中国南北气候过渡带和东西地理交会处,研究南阳盆地的土壤呼吸温度敏感性对探究中国陆地生态系统碳循环过程的气候变化的响应和适应有重要意义.土壤呼吸温度敏感系数Q10值是模拟全球变暖与生态系统碳释放之间反馈强度的重... 南阳盆地处于中国南北气候过渡带和东西地理交会处,研究南阳盆地的土壤呼吸温度敏感性对探究中国陆地生态系统碳循环过程的气候变化的响应和适应有重要意义.土壤呼吸温度敏感系数Q10值是模拟全球变暖与生态系统碳释放之间反馈强度的重要参数,利用ACE自动土壤呼吸测量仪对南阳市郊的农田裸地进行土壤呼吸探测,对研究地的土壤呼吸变化的温度敏感性进行评析.结果表明研究地的土壤呼吸随土壤表层温度上升呈上升趋势,通过分析得出研究地土壤呼吸温度敏感系数Q_(10)为1.75.土壤表层温度、土壤相对湿度在不同程度上影响着土壤呼吸变化,其中土壤表层温度的影响最为显著(R^2=0.4858). 展开更多
关键词 中国南北气候过渡带 南阳盆地 土壤呼吸温度敏感性 裸地 q10
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Diurnal and Seasonal Dynamics of Soil Respiration at Temperate Leymus Chinensis Meadow Steppes in Western Songnen Plain, China 被引量:17
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作者 WANG Ming LIU Xingtu +4 位作者 ZHANG Jitao LI Xiujun WANG Guodong LI Xiaoyu LU Xinrui 《Chinese Geographical Science》 SCIE CSCD 2014年第3期287-296,共10页
To evaluate the diurnal and seasonal variations in soil respiration (Rs) and understand the controlling factors, we measured carbon dioxide (CO2) fluxes and their environmental variables using a LI-6400 soil CO2 f... To evaluate the diurnal and seasonal variations in soil respiration (Rs) and understand the controlling factors, we measured carbon dioxide (CO2) fluxes and their environmental variables using a LI-6400 soil CO2 flux system at a temperate Leymus chinensis meadow steppe in the western Songnen Plain of China in the growing season (May-October) in 2011 and 2012. The diurnal patterns of soil respiration could be expressed as single peak curves, reaching to the maximum at 11:00-15:00 and falling to the minimum at 21:00-23:00 (or before dawn). The time-window between 7:00 and 9:00 could be used as the optimal measuring time to represent the daily mean soil CO2 efflux. In the growing season, the daily value of soil CO2 efflux was moderate in late spring (1.06-2.51μnol/(m2.s) in May), increased sharply and presented a peak in summer (2.95-3.94 μmol/(m2.s) in July), and then decreased in autumn (0.74-0.97 μmol/(m2.s) in October). Soil temperature (Ts) exerted dominant control on the diurnal and seasonal variations of soil respiration. The temperature sensitivity of soil respiration (Q10) exhibited a large seasonal variation, ranging from 1.35 to 3.32, and decreased with an increasing soil temperature. Rs gradually increased with increasing soil water content (Ws) and tended to decrease when Ws exceeded the optimum water content (27%) of Rs. The Ts and Ws had a confounding effect on Rs, and the two-variable equations could account for 72% of the variation in soil respiration (p 〈 0.01). 展开更多
关键词 soil respiration Leymus chinensis temperature sensitivity of soil respiration (q10) soil temperature soil water content
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Response of Ecosystem Respiration to Experimental Warming and Clipping at Daily Time Scale in an Alpine Meadow of Tibet 被引量:12
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作者 FU Gang SHEN Zhen-xi +4 位作者 ZHANG Xian-zhou YU Cheng-qun ZHOU Yu-ting LI Yun-long YANG Peng-wan 《Journal of Mountain Science》 SCIE CSCD 2013年第3期455-463,共9页
The alpine meadow, as one of the typical vegetation types on the Tibetan Plateau, is one of the most sensitive terrestrial ecosystems to climate warming. However, how climate warming affects the carbon cycling of the ... The alpine meadow, as one of the typical vegetation types on the Tibetan Plateau, is one of the most sensitive terrestrial ecosystems to climate warming. However, how climate warming affects the carbon cycling of the alpine meadow on the Tibetan Plateau is not very dear. A field experiment under controlled experimental warming and clipping conditions was conducted in an alpine meadow on the Northern Tibetan Plateau since July 2008. Open top chambers (0TCs) were used to simulate climate warming. The main objective of this study was to examine the responses of ecosystem respiration (Reco) and its temperature sensitivity to experimental warming and clipping at daily time scale. Therefore, we measured Reco once or twice a month from July to September in 2010, from June to September in 2011 and from August to September in 2012. Air temperature dominated daily variation of Reco whether or not experimental warming and clipping were present. Air temperature was exponentially correlated with Reco and it could significantly explain 58-96% variation of Redo at daily time scale. Experimental warming and clipping decreased daily mean Reco by 5.8-37.7% and -11.9-23.0%, respectively, although not all these changes were significant. Experimental warming tended to decrease the temperature sensitivity of Reco, whereas clipping tended to increase the temperature sensitivity of Reco at daily time scale. Our findings suggest that Reco wasmainly controlled by air temperature and may acclimate to climate warming due to its lower temperature sensitivity under experimental warming at daily time scale. 展开更多
关键词 ACCLIMATION Air temperature Open topchamber temperature sensitivity Respirationquotient q10)
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温带阔叶林、针叶林和针阔混交林土壤呼吸的比较研究 被引量:57
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作者 牟守国 《土壤学报》 CAS CSCD 北大核心 2004年第4期564-570,共7页
对韩国广陵树木园的阔叶林、针叶林和针阔混交林的土壤呼吸排放量进行观测、分析和比较 ,研究土壤呼吸与环境因子之间的相互关系 ,从中探究各森林植被类型之间产生土壤呼吸差别的原因。利用Q10 模型计算出阔叶林、针叶林和针阔混交林的... 对韩国广陵树木园的阔叶林、针叶林和针阔混交林的土壤呼吸排放量进行观测、分析和比较 ,研究土壤呼吸与环境因子之间的相互关系 ,从中探究各森林植被类型之间产生土壤呼吸差别的原因。利用Q10 模型计算出阔叶林、针叶林和针阔混交林的土壤呼吸Q10 值为 3 6、3 8和 3 2 ,再根据对当地各观测站土壤温度的连续观测数据 ,计算出阔叶林、针叶林和针阔混交林的土壤呼吸日均排放量 ,依次分别为CO2 15 12、15 10和 13 99gm-2 。 展开更多
关键词 温带 阔叶林 针叶林 针阔混交林 土壤呼吸 土壤温度 土壤水分含量
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Dependence of Soil Respiration on Soil Temperature and Soil Moisture in Successional Forests in Southern China 被引量:17
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作者 Xu-Li Tang Guo-Yi Zhou +4 位作者 Shu-Guang Liu De-Qiang Zhang Shi-Zhong Liu Jiong Li Cun-Yu Zhou 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第6期654-663,共10页
The spatial and temporal variations in soil respiration and its relationship with biophysical factors In forests near the Tropic of Cancer remain highly uncertain. To contribute towards an Improvement of actual estima... The spatial and temporal variations in soil respiration and its relationship with biophysical factors In forests near the Tropic of Cancer remain highly uncertain. To contribute towards an Improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured In three successional subtropical forests at the Dlnghuahan Nature Reserve (DNR) In southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and Its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared In successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates In the cool dry season (October-March). Soil respiration measured at these forests showed a clear Increasing trend with the progressive succession. Annual mean (± SD) soil respiration rate In the DNR forests was (9.0 ± 4.6) Mg CO2-C/hm^2 per year, ranging from (6.1 ± 3.2) Mg CO2-C/hm^2 per year in early successional forests to (10.7 ± 4.9) Mg CO2-C/hm^2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation In DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture Increased with progressive succession processes. This increase is caused, in part, by abundant respirators In advanced-successional forest, where more soil moisture is needed to maintain their activities. 展开更多
关键词 Dinghushan Nature Reserve moisture sensitivity q10 soil CO2 efflux soil respiration subtropical forests successional forests temperature sensitivity Tropic of Cancer.
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Spatial patterns in temperature sensitivity of soil respiration in China: Estimation with inverse modeling 被引量:4
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作者 ZHOU Tao1,2, SHI PeiJun1,2, HUI DaFeng3 & LUO YiQi4 1 State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China 2 Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, Beijing 100875, China +1 位作者 3 Department of Biological Sciences, Tennessee State University, Nashville, TN 37209, USA 4 Department of Botany and Microbiology, University of Oklahoma, Norman, OK 73019, USA 《Science China(Life Sciences)》 SCIE CAS 2009年第10期982-989,共8页
Temperature sensitivity of soil respiration (Q10) is an important parameter in modeling the effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated t... Temperature sensitivity of soil respiration (Q10) is an important parameter in modeling the effects of global warming on ecosystem carbon release. Experimental studies of soil respiration have ubiquitously indicated that Q10 has high spatial heterogeneity. However, most biogeochemical models still use a constant Q10 in projecting future climate change and no spatial pattern of Q10 values at large scales has been derived. In this study, we conducted an inverse modeling analysis to retrieve the spatial pattern of Q10 in China at 8 km spatial resolution by assimilating data of soil organic carbon into a proc-ess-based terrestrial carbon model (CASA model). The results indicate that the optimized Q10 values are spatially heterogeneous and consistent to the values derived from soil respiration observations. The mean Q10 values of different soil types range from 1.09 to 2.38, with the highest value in volcanic soil, and the lowest value in cold brown calcic soil. The spatial pattern of Q10 is related to environmental factors, especially precipitation and top soil organic carbon content. This study demonstrates that inverse modeling is a useful tool in deriving the spatial pattern of Q10 at large scales, with which being incorporated into biogeochemical models, uncertainty in the projection of future carbon dynamics could be potentially reduced. 展开更多
关键词 temperature sensitivity q10 SOIL RESPIRATION GLOBAL WARMING INVERSE analysis
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