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川西亚高山流域水碳平衡研究 被引量:4
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作者 孙鹏森 刘宁 +1 位作者 刘世荣 孙阁 《植物生态学报》 CAS CSCD 北大核心 2016年第10期1037-1048,共12页
森林生态系统的产水量与固碳效益之间存在着一种可交易的平衡关系。基于Wa SSI-C水碳耦合模型和趋势分析,研究了1982–2006年川西杂古脑河上游22个子流域内不同植被类型空间分布对水碳平衡的影响并分析了其水碳耦合关系,发现:1)针叶林... 森林生态系统的产水量与固碳效益之间存在着一种可交易的平衡关系。基于Wa SSI-C水碳耦合模型和趋势分析,研究了1982–2006年川西杂古脑河上游22个子流域内不同植被类型空间分布对水碳平衡的影响并分析了其水碳耦合关系,发现:1)针叶林主导的流域在生长季增加土壤水分入渗的功能明显高于其他植被类型,但不足以补偿其高蒸散带来的水分消耗,因而其年平均土壤含水量明显低于高山草甸和混交林类型;且森林土壤含水量随着森林覆盖率的升高而降低。2)25年的土壤水分蓄变量的平均值,高山草甸流域为–44 mm,混交林为–18 mm,针叶林为–5 mm,说明川西亚高山植被的整体维持稳定产水量及其潜力在下降,其中高山草甸流域下降趋势尤为显著。3)流域产流量和净生态系统生产力具有显著负相关性,且不同植被组成对固碳和产水效益的转化具有重要影响:高山草甸主导的子流域具有较高的产水量和较低的固碳能力,常绿针叶林主导的子流域具有较高固碳能力和较低产水量,且森林覆盖率越高,产水量越低。三种植被类型的净生态系统生产力在研究期间均呈现上升趋势,且高山草甸的上升趋势显著。 展开更多
关键词 水碳平衡 耦合 文响应单元 土壤分蓄变量 WaSSI-C耦合模型
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变化环境下流域水-碳平衡演化研究综述 被引量:4
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作者 段凯 孙阁 刘宁 《水利学报》 EI CSCD 北大核心 2021年第3期300-309,共10页
流域水量平衡与碳平衡通过植物光合作用与蒸散发过程紧密相联。在全球环境变化的背景下,研究流域水-碳平衡的耦合关系与对变化环境的响应规律对于发展生态水文科学具有重要科学意义,也可为区域水安全保障、生态系统服务功能评价、气候... 流域水量平衡与碳平衡通过植物光合作用与蒸散发过程紧密相联。在全球环境变化的背景下,研究流域水-碳平衡的耦合关系与对变化环境的响应规律对于发展生态水文科学具有重要科学意义,也可为区域水安全保障、生态系统服务功能评价、气候变化适应性对策制定等提供科学支撑。本文从水循环与碳循环要素的监测、水-碳耦合关系的量化和模拟、变化环境对水-碳平衡的干扰、流域尺度上水-碳平衡演化规律识别与归因等方面对相关研究进展进行综述,探讨当前的研究热点、面临的问题与挑战、以及未来的发展趋势。 展开更多
关键词 -耦合 流域-平衡 变化环境 研究进展
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Effects of water temperature and dietary carbohydrate levels on growth and energy budget of juvenile Litopenaeus vannamei 被引量:4
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作者 王兴强 马甡 董双林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第3期318-324,共7页
A 3×3 factorial experiment was conducted to determine the effects of water temperature (22 ℃, 27℃ and 32℃) and dietary carbohydrate (CBH) levels (15.47%, 29.15% and 41.00%) on growth, food consumption, feed ef... A 3×3 factorial experiment was conducted to determine the effects of water temperature (22 ℃, 27℃ and 32℃) and dietary carbohydrate (CBH) levels (15.47%, 29.15% and 41.00%) on growth, food consumption, feed efficiency, apparent digestibility coefficient and energy budget of juvenile Lito- penaeus vannamei. The results showed that, at each dietary CBH level, specific growth rate, food con- sumption and apparent digestibility coefficient generally increased, while feed efficiency decreased with increasing water temperatures. Specific growth rate and food consumption were the highest in the shrimps fed with diet of 29.15% CBH, closely followed by those with 15.47% CBH, and those with 41.00% CBH had the lowest value. 展开更多
关键词 Litopenaeus vannamei water temperature CARBOHYDRATE GROWTH energy budget
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Progress in the Study on the Phase Equilibria of the CO2·H2O and CO2-HeO-NaCI Systems 被引量:6
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作者 吉远辉 吉晓燕 +3 位作者 冯新 刘畅 吕玲红 陆小华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期439-448,共10页
To study the feasibility of CO2 geological sequestration,it is needed to understand the complicated mul- tiple-phase equilibrium and the densities of aqueous solution with CO2 and multi-ions under wide geological cond... To study the feasibility of CO2 geological sequestration,it is needed to understand the complicated mul- tiple-phase equilibrium and the densities of aqueous solution with CO2 and multi-ions under wide geological condi- tions(273.15—473.15K,0—60MPa),which are also essential for designing separation equipments in chemical or oil-related industries.For this purpose,studies on the relevant phase equilibria and densities are reviewed and ana- lyzed and the method to improve or modify the existing model is suggested in order to obtain more reliable pre- dictions in a wide temperature and pressure range.Besides,three different models(the electrolyte non random two-liquid(ELECNRTL),the electrolyte NRTL combining with Helgeson model(ENRTL-HG),Pitzer activity co- efficient model combining with Helgeson model(PITZ-HG))are used to calculate the vapor-liquid phase equilib- rium of CO2-H2O and CO2-H2O-NaCl systems.For CO2-H2O system,the calculation results agree with the experi- mental data very well at low and medium pressure(0—20MPa),but there are great discrepancies above 20MPa.For the water content at 473.15K,the calculated results agree with the experimental data quite well.For the CO2-H2O-NaCl system,the PITZ-HG model show better results than ELECNRTL and ENRTL-HG models at the NaCl concentration of 0.52mol·L -1 .Bur for the NaCl concentration of 3.997mol·L -1 ,using the ELECNRTL and ENRTL-HG models gives better results than using the PITZ-HG model.It is shown that available experimental data and the thermodynamic calculations can satisfy the needs of the calculation of the sequestration capacity in the temperature and pressure range for disposal of CO2 in deep saline aquifers.More experimental data and more accu- rate thermodynamic calculations are needed in high temperature and pressure ranges(above 398.15K and 31.5MPa). 展开更多
关键词 CO2-H2O CO2-H2O-NaCl high temperature high pressure phase equilibrium DENSITY
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Aboveground net primary productivity and soil respiration display different responses to precipitation changes in desert grassland 被引量:5
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作者 Lihua Zhang Junfeng Wang +2 位作者 Ruifeng Zhao Yafei Guo Lianyi Hao 《Journal of Plant Ecology》 SCIE CSCD 2022年第1期57-70,共14页
Precipitation(PPT)changes affect both aboveground vegetation dynamics and belowground carbon cycling processes,particularly in arid and semiarid regions.However,it remains unclear how extreme PPT variation can affect ... Precipitation(PPT)changes affect both aboveground vegetation dynamics and belowground carbon cycling processes,particularly in arid and semiarid regions.However,it remains unclear how extreme PPT variation can affect soil carbon sequestration potential.A 3-year PPT manipulation experiment with five levels(±40%,±20%and ambient PPT)was conducted in a desert grassland of western Loess Plateau.Aboveground net primary productivity(ANPP)and soil respiration(Rs)were measured to examine whether the responses of ANPP and Rs to PPT changes displayed a double asymmetry model.The ANPP was more sensitive to extreme drought than extreme wet treatments in wet and dry years,which displayed a negative asymmetric model.The change in ANPP was mainly due to the direct effect of PPT change,and plant density variation also exerted some influence in the dry year.In contrast,Rs displayed a positive asymmetry response to PPT change in dry year.This may be ascribed to enhanced autotrophic respiration due to the enhanced positive responses of plant growth and ANPP to wet treatments as well as stronger birch effect of rainfall events on heterotrophic respiration.The saturating response of Rs to extreme drought(−40%PPT treatment)was also found in the dry year.Nevertheless,the response of Rs to PPT change displayed a negative asymmetry model in wet years.The contrasting models for ANPP and Rs in response to altered PPT regime suggest that extreme wet or dry treatments may increase soil C pools effluxes toward debt in this desert grassland. 展开更多
关键词 primary production plant growth soil respiration soil carbon balance extreme precipitation desert grassland asymmetry response
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Chinese Forest Ecosystem Research Network and Its Development
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作者 WANGBing CUIXianghui YANGFengwei 《Chinese Forestry Science and Technology》 2004年第1期25-30,共6页
Chinese Forest Ecosystem Research Network, established in late 1950s and directly constructedand administered by the Science and Technology Department of State Forestry Administration of China,is a large ecology resea... Chinese Forest Ecosystem Research Network, established in late 1950s and directly constructedand administered by the Science and Technology Department of State Forestry Administration of China,is a large ecology research network focuses on long-term ecosystem fixed-observation. It embodies 15 sitesthat represent diverse ecosystems and research priorities, including 6 state-level sites. CFERN Officecoordinates communications, network publications, and research-planning activities. CFERN uses theadvanced ground and spatial observation technologies such as RS, GPS, GIS to study the structure,functional laws and feedback mechanism of Chinese forest ecosystem, as well as its effects on Chinassocial and economic development. The main tasks carried out by CFERN are: (1) construction of thedatabase on the structure and functions of Chinese forest ecosystem and its ecological environmentalfactors; (2) the database construction of forest resources, ecological environment, water resources andrelated social economy in both regional and national scales; (3) the establishment of an evaluation systemof forest ecological effects in Chinas main drainage areas; (4) the establishment of a forest environmentmonitoring network and a dynamic prediction and alarm system. 展开更多
关键词 CFERN forest ecosystem eco-hydrological functions carbon balance
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新型垂直筛板在综合塔回清段的应用
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作者 唐万全 《氮肥技术》 1995年第3期52-54,共3页
我厂现为3.5万tNH<sub>3</sub>/a生产能力。合成系统有φ800系列壹套,4M8压缩机4台和4M16压缩机2台,买际已达年产四万吨氨能力。碳化系统为2台φ2600碳化主塔。
关键词 综合塔 新型垂直 垂直筛板塔 回收清洗段 平衡 压缩机 流程简图 设计参数 稀氨 化工艺
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