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Prediction of carbon exchanges between China terrestrial ecosystem and atmosphere in 21st century

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Science China Earth Sciences 2008年第6期51卷 885-898页

作者： JI JinJun HUANG Mei li kerang Chinese Ecosystem Research Network Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

The projected changes in carbon exchange between China terrestrial ecosystem and the atmosphere and vegetation and soil carbon storage during the 21st century were investigated using an atmos-phere-vegetation interaction model (AVIM2). The results show that in the coming 100 a, for SRES B2 scenario and constant atmospheric CO2 concentration, the net primary productivity (NPP) of terrestrial ecosystem in China will be decreased slowly, and vegetation and soil carbon storage as well as net ecosystem productivity (NEP) will also be decreased. The carbon sink for China terrestrial ecosystem in the beginning of the 20th century will become totally a carbon source by the year of 2020, while for B2 scenario and changing atmospheric CO2 concentration, NPP for China will increase continuously from 2.94 GtC·a?1 by the end of the 20th century to 3.99 GtC·a?1 by the end of the 21st century, and vegetation and soil carbon storage will increase to 110.3 GtC. NEP in China will keep rising during the first and middle periods of the 21st century, and reach the peak around 2050s, then will decrease gradually and approach to zero by the end of the 21st century.

关键词： carbon cycle AVIM2 climate change B2 scenario China terrestrial ecosystems

Synthesis and Characterization of a Novel Soluble Diethoxy Phosphoryl Chitosan

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Chinese Journal of Chemistry 2012年第2期30卷 413-417页

作者： Ma,li li,kerang li,limin liu,Pu Department of Chemistry Zhengzhou UniversityZhengzhouHenan 450001China

A simple and efficient method for the preparation of a novel soluble chitosan derivative, diethoxy phosphoryl chitosan （PH-chitosan）, has been developed. Ph-chitosan was characterized by elemental analysis, FT-IR, NMR, ICP, XRD, TG and SEM, respectively. The chemical identity of PH-chitosan was determined by FT-IR and confirmed by NMR, and those results unequivocally demonstrated that diethoxy phosphoryl groups were grafted onto the amino and hydroxyl groups of chitosan. The results of XRD indicated that the crystalline structure of chitosan was destroyed due to the incorporation of diethoxy phosphoryl group resulting in loss of hydrogen bond. The analysis of TG demonstrated that PH-chitosan was less thermal stable than chitosan. This simple synthetic method provided a new and available approach to prepare a soluble high molecule weight chitosan derivative.

关键词： chitosan diethoxy phosphoryl chitosan synthesis characterization

Vegetation and soil carbon storage in China

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Science China Earth Sciences 2004年第1期47卷 49-57页

作者： li kerang, WANG Shaoqiang & CAO MingkuiInstitute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Department of Geography, Maryland University, College Park,MD 20742, USA Correspondence should be addressed to li kerang Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China Department of Geography Maryland University College Park MD 20742 United States

This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors.

关键词： carbon storage, vegetation, soil, China.

THE LONG-RANGE TREND OF TEMPERATURE VARIATION IN CHINA:1951 TO 1988

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Journal of Geographical Sciences 1993年第4期 82-96页

作者： li kerang lin Xianchao Wei-chyung Wang Institute of Geography CAS Center of Atmospheric Science Research New York State University

By using the data of surface air temperature from 1951to 1988,the processes of temperature variation in China and their spatial and temporal distribution are analyzed,especially the trend of variation and warming from decade to *** results show that the decade average temperature has been rising from the 1950s to the present time and is 0.2°C higher in the 1980s than in the ***,the intensity of warming amplifies with the zones from south to *** most of the areas in China;temperature rises in winter and spring and declines or rises slightly in *** is a general trend of warming in winter and cooling in summer for temperature variation in China during the recent 40 years.

关键词： temperature climate change

Multi-scale observation and cross-scale mechanistic modeling on terrestrial ecosystem carbon cycle

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Science China Earth Sciences 2005年第z1期48卷 17-32页

作者： CAO Mingkui YU Guirui liU Jiyuan li kerang Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

To predict global climate change and to implement the Kyoto Protocol for stabilizing atmospheric greenhouse gases concentrations require quantifying spatio-temporal variations in the terrestrial carbon sink accurately. During the past decade multi-scale ecological experiment and observation networks have been established using various new technologies (e.g. controlled environmental facilities, eddy covariance techniques and quantitative remote sensing), and have obtained a large amount of data about terrestrial ecosystem carbon cycle. However, uncertainties in the magnitude and spatio-temporal variations of the terrestrial carbon sink and in understanding the underlying mechanisms have not been reduced significantly. One of the major reasons is that the observations and experiments were conducted at individual scales independently, but it is the interactions of factors and processes at different scales that determine the dynamics of the terrestrial carbon sink. Since experiments and observations are always conducted at specific scales, to understand cross-scale interactions requires mechanistic analysis that is best to be achieved by mechanistic modeling. However, mechanistic ecosystem models are mainly based on data from single-scale experiments and observations and hence have no capacity to simulate mechanistic cross-scale interconnection and interactions of ecosystem processes. New-generation mechanistic ecosystem models based on new ecological theoretical framework are needed to quantify the mechanisms from micro-level fast eco-physiological responses to macro-level slow acclimation in the pattern and structure in disturbed ecosystems. Multi-scale data-model fusion is a recently emerging approach to assimilate multi-scale observational data into mechanistic, dynamic modeling, in which the structure and parameters of mechanistic models for simulating cross-scale interactions are optimized using multi-scale observational data. The models are validated and evaluate

关键词： global climate change, terrestrial carbon sink, multi-scale observation, data-model fusion, cross-scale mechanistic modeling.

离子液体中壳聚糖磷酸吡哆醛席夫碱衍生物的合成与表征

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化工学报 2013年第4期64卷 1499-1503页

作者：李克让徐民张帅刘蒲郑州大学化学与分子工程学院河南郑州450001 安阳市质量技术监督检验测试中心河南安阳455001

引言壳聚糖是自然界中唯一含有氨基的碱性多糖,具有多样的生物活性、极好的生物相容性、生物可降解性以及无毒性等特性,是一种新兴的生物功能材料[1-3]。磷酸吡哆醛是维生素B6参与多种代谢反应的一种活性形式。磷酸吡哆醛作为一种辅酶... 详细信息

引言壳聚糖是自然界中唯一含有氨基的碱性多糖,具有多样的生物活性、极好的生物相容性、生物可降解性以及无毒性等特性,是一种新兴的生物功能材料[1-3]。磷酸吡哆醛是维生素B6参与多种代谢反应的一种活性形式。磷酸吡哆醛作为一种辅酶参与所有转氨基反应及一些氨基酸的脱羧及脱氢反应。研究表明,磷酸吡哆醛不但可以用于预防治疗高血压、心血管疾病及糖尿病等,还可用于治疗迟发性运动障碍和治疗难治性儿童期癫痫[4-5]。王涛等[6]以壳聚糖微球为载体,然后固定磷酸吡哆醛等制备得到了低密度脂蛋白亲和吸附剂。

关键词：壳聚糖离子液体磷酸吡哆醛席夫碱衍生物

Impacts of land use and climate change on regional net primary productivity

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Journal of Geographical Sciences 2004年第3期14卷 349-358页

作者：高志强刘纪远曹明奎 li kerang TAO Bo Inst. of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Combined with recent historical climate data and two periods of land use datasets from remote sensing data, we test the net primary productivity (NPP) data sets in North Chinamodelled by the satellite data-driven Global Production Efficiency Model (GLO-PEM) for detecting thewidespread spatial and temporal characteristics of the impacts of climate and land use change onthe regional NPP. Our results show that over the past 20 years, the mean annual temperature in thestudy region has remarkably increased by more than 0.064 ℃, but over the same period, there hasbeen a 1.49 mm decrease in annual precipitation and decrease in NPP by an annual rate of 6.9 *** NPP changes in the study region were greatly affected by the average temperature andprecipitation by ten-day periods as well as the seasonal temperature and precipitation in the studyregion. The correlation between seasonal NPP and seasonal precipitation and temperature is highlyconsistent with land cover spatially, and the correlation coefficient changes with the changes ofvegetation types. The analysis reveals that the related areas in land use change only take up 5.45%of the whole studied region, so the climate changes dominate the impacts on the NPP in the wholestudy region (90% of the total). However, land use plays an absolute dominative role in areas withland cover changes, accounting for 97% of the total. From 1981 to 2000, the NPP in the whole studyregion remarkably reduced due to obvious precipitation decrease and temperature rise. Between twoperiods of land use (about 10 years), the changes in climate are predicted to promote a decrease inNPP by 78 ( + -0.6) TgC, and integrated impacts of climate changes and land use to promote adecrease in NPP by 87(+-0.8) TgC.

关键词： climate change land use change NPP GLO-PEM North China Northeast China

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M8300多相织机及其经济性分析

上海纺织科技 2002年第3期30卷 28-30页

作者：李克让陈明东华大学机械学院 200051

介绍了多相织机的概念和种类 ,解释了M 830 0多相织机的织造原理和技术特征 ,并在此基础上分析了其优点和经济性 ,展望了其未来发展方向。

关键词： M8300多相织机经济性新型织机

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植被地理分布对气候变化的适应性研究

地理科学进展 2010年第11期29卷 1326-1332页

作者：於琍李克让陶波徐明国家气候中心北京100081 中国气象局气候变化中心北京100081 中国科学院地理科学与资源研究所北京100101

开展气候变化对植被生产力及分布格局影响的研究较多,但分析植被地理分布与气候条件之间适应关系的研究还不多见。本研究以气候与植被关系为基础,采用植被对气候变化响应的时滞性,模拟不同植被类型对气候变化的动态响应过程,以当前气候... 详细信息

开展气候变化对植被生产力及分布格局影响的研究较多,但分析植被地理分布与气候条件之间适应关系的研究还不多见。本研究以气候与植被关系为基础,采用植被对气候变化响应的时滞性,模拟不同植被类型对气候变化的动态响应过程,以当前气候条件和未来气候变化情景下植被地理分布实际发生和潜在的转变情况来定量表达植被地理分布与气候条件间的适应关系,评价植被地理分布对气候变化的适应性。结果表明,当前气候条件下(1961—1990年),中国植被对气候变化适应性总体较好,适应性较差的地方主要为森林—灌丛和草地—荒漠的交界处,植被的地理分布已经有所改变,约占5%;在华东地区森林—灌丛过渡带、内蒙古地区的灌丛—草地过渡带以及青藏高原南部的草地生态系统等对气候的适应性也较差,约占35%,这些地区的植被有退化的倾向,植被的地理分布有可能会发生变化。中国植被对未来气候变化(IPCC-SRES-A2情景2071-2100)的适应性总体较好,84%的植被变化表现为正向的变化,特别是在西北地区,未来气候条件将有所改善,这些地区的植被覆盖可能会有所提高。植被潜在的变化中约79%的植被可以适应未来的气候,但在青藏高原南部和内蒙古地区及西北的部分地区的草地生态系统对未来气候变化的适应性较差,有退化的倾向。

关键词：植被地理分布气候变化适应性模拟中国