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18篇 您的检索式:作者名="KERANG LI"
    题名 作者 年代 出处 被引量
1Vegetation and soil carbon storage in China显示文摘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.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 2004Science China Earth Sciences2004,47,1:60
2Prediction of carbon exchanges between China terrestrial ecosystem and atmosphere in 21st century显示文摘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.JI JinJun HUANG Mei LI KeRang 2008Science China Earth Sciences2008,51,6:48
3Multi-scale observation and cross-scale mechanistic modeling on terrestrial ecosystem carbon cycle显示文摘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 evaluated at different spatial and temporal scales and real-time observational data are assimilated continuously into dynamic modeling for predicting and forecasting ecosystem changes realistically. in summary, a breakthrough in terrestrial carbon sink research requires using approaches of multi-scale observations and cross-scale modeling to understand and quantify interconnections and interactions among ecosystem processes at different scales and their controls over ecosystem carbon cycle.CAO Mingkui YU Guirui LIU Jiyuan LI Kerang 2005Science China Earth Sciences2005,48,z1:17
4Impacts of land-use and climate changes on ecosystem productivity and carbon cycle in the cropping-grazing transitional zone in China显示文摘The impact of land-use/land-cover and climate changes on ecosystem productivity and carbon cycle is one of the most important issues in global change studies. In the past 20 years, the climate and land-use in China have changed significantly and have had important ecological consequences, especially in ecologically sensitive regions, e.g. the cropping-grazing transition zone (CGTZ). Here we present a study that used a process-based ecosystem model and data of land-use changes based on remote sensing and of climate change at high spatial and temporal resolution to estimate the impacts of land-use and climate changes on net primary productivity (NPP), vegetation carbon storage, soil heterotrophic respiration (HR), carbon storage and net ecosystem productivity (NEP) in the CGTZ of China. The results show that the warming and decreases in precipitation in CGTZ reduced NPP by 3.4%, increased HR by 4.3%, and re- duced annual mean total NEP by 33.7Tg from the 1980s to the 1990s. Although carbon storage in vegetation and soil was increasing because the mean NPP for the period was higher than HR, the decreasing NEP indicate that climate change reduced the carbon uptake rate. However, land-use changes in this zone caused increases in NPP by 3.8%, vegetation carbon storage by 2.4%, and annual total NEP by 0.59Tg. The land-use changes enhanced ecosystem carbon up- take, but not enough to offset the negative effect of the climate change. The climate change had greater impacts than the land-use change for the whole CGTZ zone, but had smaller impacts than the land-use change in the regions where it occurred.GAO Zhiqiang LIU Jiyuan CAO Mingkui LI Kerang TAO Bo 2005Science China Earth Sciences2005,48,9:16
5Association between AKT1 gene polymorphisms and depressive symptoms in the Chinese Han population with major depressive disorder显示文摘For this study, 461 Chinese Han patients with depressive disorder were recruited. The AKT1 genotype and allele distribution were determined by PCR amplification and direct sequencing. UNPHASED software was used to analyze associations between the 17-item Hamilton Depression Rating Scale, total score, four factors and the AKT1 rs2494746 and rs3001371 polymorphisms. The results indicate that there is a significant association between suicidal ideation and anxiety symptoms in depressed patients and the rs2494746 polymorphism. The other AKT1 polymorphism, rs3001371, was significantly associated with work and activities. Patients with the rs3001371-A allele had a significantly more severe illness compared to patients with the rs3001371-G allele. Thus, AKT1 polymorphisms appear to be associated with depression severity, anxiety symptoms, work and activities, and suicide attempts in patients with depressive disorder.Chunxia Yang Ning Sun Yan Ren Yan Sun Yong Xu Aiping Li Kewen Wu Kerang Zhang 2012Neural Regeneration Research2012,7,3:8
6Biomass Carbon Sequestration by Planted Forests in China显示文摘The planted forest area and carbon sequestration have increased significantly in China,because of large-scale reforestation and afforestation in the past decades.In this study,we developed an age-based volume-to-biomass method to estimate the carbon storage by planted forests in China in the period of 1973-2003 based on the data from 1209 field plots and national forest inventories.The results show that the total carbon storage of planted forests was 0.7743 Pg C in 1999-2003,increased by 3.08 times since the early 1970s.The carbon density of planted forests varied from 10.6594 Mg/ha to 23.9760 Mg/ha and increased by 13.3166 Mg/ha from 1973-1976 to 1999-2003.Since the early 1970s,the planted forests in China have been always a carbon sink,and the annual rate of carbon sequestration was 0.0217 Pg C/yr.The carbon storage and densities of planted forests varied greatly in space and time.The carbon storage of Middle South China was in the lead in all regions,which accounted for 23%-36% of national carbon storage.While higher C densities (from 17.79 Mg/ha to 26.05 Mg/ha) were usually found in Northeast China.The planted forests in China potentially have a high carbon sequestration since a large part of them are becoming mature and afforestation continues to grow.XU Xinliang LI Kerang 2010Chinese Geographical Science2010,20,4:8
7土地利用和气候变化对区域净初级生产力影响(英文)显示文摘Combined with recent historical climate data and two periods of land use data sets from remote sensing data, we test the net primary productivity (NPP) data sets in North China modelled by the satellite data-driven Global Production Efficiency Model (GLO-PEM) for detecting the widespread spatial and temporal characteristics of the impacts of climate and land use change on the regional NPP. Our results show that over the past 20 years, the mean annual temperature in the study region has remarkably increased by more than 0.064 oC, but over the same period, there has been a 1.49 mm decrease in annual precipitation and decrease in NPP by an annual rate of 6.9 TgC. The NPP changes in the study region were greatly affected by the average temperature and precipitation by ten-day periods as well as the seasonal temperature and precipitation in the study region. The correlation between seasonal NPP and seasonal precipitation and temperature is highly consistent with land cover spatially, and the correlation coefficient changes with the changes of vegetation 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 whole study region (90% of the total). However, land use plays an absolute dominative role in areas with land cover changes, accounting for 97% of the total. From 1981 to 2000, the NPP in the whole study region remarkably reduced due to obvious precipitation decrease and temperature rise. Between two periods of land use (about 10 years), the changes in climate are predicted to promote a decrease in NPP by 78 (±0.6) TgC, and integrated impacts of climate changes and land use to promote a decrease in NPP by 87(±0.8) TgC.高志强 刘纪远 曹明奎 LI Kerang TAO Bo 2004Journal of Geographical Sciences2004,14,3:8
8Abnormal activation of the occipital lobes during emotion picture processing in major depressive disorder patients显示文摘A large number of studies have demonstrated that depression patients have cognitive dysfunction. With recently developed brain functional imaging, studies have focused on changes in brain function to investigate cognitive changes. However, there is still controversy regarding abnormalities in brain functions or correlation between cognitive impairment and brain function changes. Thus, it is important to design an emotion-related task for research into brain function changes. We selected positive, neutral, and negative pictures from the International Affective Picture System. Patients with major depressive disorder were asked to judge emotion pictures. In addition, functional MRI was performed to synchronously record behavior data and imaging data. Results showed that the total correct rate for recognizing pictures was lower in patients compared with normal controls. Moreover, the consistency for recognizing pictures for depressed patients was worse than normal controls, and they frequently recognized positive pictures as negative pictures. The consistency for recognizing pictures was negatively correlated with the Hamilton Depression Rating Scale. Functional MRI suggested that the activation of some areas in the frontal lobe, temporal lobe, parietal lobe, limbic lobe, and cerebellum was enhanced, but that the activation of some areas in the frontal lobe, parietal lobe and occipital lobe was weakened while the patients were watching positive and neutral pictures compared with normal controls. The activation of some areas in the frontal lobe, temporal lobe, parietal lobe, and limbic lobe was enhanced, but the activation of some areas in the occipital lobe were weakened while the patients were watching the negative pictures compared with normal controls. These findings indicate that patients with major depressive disorder have negative cognitive disorder and extensive brain dysfunction. Thus, reduced activation of the occipital lobe may be an initiating factor for cognitive disorder in depressed patients.Jianying Li Cheng Xu Xiaohua Cao Qiang Gao Yan Wang Yanfang Wang Juyi Peng Kerang Zhang 2013Neural Regeneration Research2013,8,18:7
9An Analysis of the Orthogonal Crank-rocking Lever Spatial Mechanism for the Weft Insertion in Rapier Looms显示文摘On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are studied when the maximum swing angle of rocking lever and the length of outputting lever have different values, and the optimum parameters suitable for motion transmission can be chosen. At the same time some existing shortpoints of the mechanism are also pointed out.Li Kerang(李克让) Chen Ming(陈明) 2001Journal of Donghua University(English Edition)2001,18,1:6
10The norepinephrine transporter gene is associated with the retardation symptoms of major depressive disorder in the Han Chinese population显示文摘The norepinephrine transporter plays an important role in the pathophysiology and pharmacological treatment of major depressive disorder.Consequently,the norepinephrine transporter gene is an attractive candidate in major depressive disorder research.In the present study,we evaluated the depression symptoms of subjects with major depressive disorder,who were all from the North of China and of Han Chinese origin,using the Hamilton Depression Scale.We examined the rela-tionship between two single nucleotide polymorphisms in the norepinephrine transporter,rs2242446 and rs5569,and the retardation symptoms of major depressive disorder using quantitative trait testing with the UNPHASED program.rs5569 was associated with depressed mood,and the GG genotype may be a risk factor for this;rs2242446 was associated with work and interest,and the TT genotype may be a risk factor for loss of interest.Our findings suggest that rs2242446 and rs5569 in the norepinephrine transporter gene are associated with the retardation symptoms of depression in the Han Chinese population.Xinrong Li Ning Sun Yong Xu Yanfang Wang Suping Li Qiaorong Du Juyi Peng Jinxiu Luo Kerang Zhang 2012Neural Regeneration Research2012,7,25:3
11Vertical Distribution of Soil Organic Carbon in China显示文摘Shaoqlang Wang Mei Huang Xuemei Shao Robert A. Mickler Kerang Li Jingjun Ji 2004Environmental Management2004,,1:2
12Climate-induced changes in the vegetation pattern of China in the 21st century显示文摘Li Yu Mingkui Cao Kerang Li 2006Ecological Research2006,,6:1
13Carbon storage in northeast China as estimated from vegetation and soil inventories显示文摘Shaoqiang Wang Chenghu Zhou Jiyuan Liu Hanqin Tian Kerang Li Xiaomei Yang 2001Environmental Pollution2001,,:1
14Modelling carbon fluxes of different forests by coupling a remote-sensing model with an ecosystem process model显示文摘Junbang Wang Jiyuan Liu Mingkui Cao Yunfeng Liu Guirui Yu Guicai Li Shuhua Qi Kerang Li 2011International Journal of Remote Sensing2011,,21:1
15Response of terrestrial carbon uptake to climate inter annual variability in China 显示文摘CAO M K Stephen D Prince LI Kerang 2003Global Change Biol2003,,9:1
16The ecosystem carbon accumulation after conversion of grasslands to pine plantations in subtropical red soil of South China 显示文摘MEI HUANG JINjUN JI KERANG LI 2007J Tellus2007,59,:1
17Synthesis and Characterization of a Novel Soluble Diethoxy Phosphoryl Chitosan显示文摘为新奇可溶的 chitosan 衍生物的准备的一个简单、有效的方法, diethoxy phosphoryl chitosan (PH-chitosan ) ,被开发了。Ph-chitosan 被元素的分析,英尺红外, NMR, ICP, XRD, TG 和 SEM 分别地描绘。PH-chitosan 的化学身份被英尺红外决定并且由 NMR,和那些证实结果不含糊地证明 diethoxy phosphoryl 组是 grafted 到上氨基并且 chitosan 的氢氧根组。XRD 的结果显示 chitosan 的水晶的结构由于 diethoxy phosphoryl 组导致氢债券的损失的加入被破坏。TG 的分析证明 PH-chitosan 比 chitosan 是更少的热马厩。这个简单合成方法提供了一条新、可得到的途径准备可溶的高分子重量 chitosan 衍生物。Ma,Li Li,Kerang Li,Limin Liu,Pu 2012Chinese Journal of Chemistry2012,30,2:0
18Dynamics of Water Jet in Water Jet Looms显示文摘On the base of the study on dynamics of water jet in water jet looms, the parameters of water jet mechanism which affect the speed of water jet are analyzed and optimized. So the stability of the water jet can be improved to raise the speed of water jet as well as weft insertion rate and to enlarge the width of woven fabrics a lot. At the same time it also points out that to increase water jet speed and to prolong its affective jet time depend mainly on the accretion of spring rate (constant)of stiffness and the diminution of plunger's cross sectional area respectively.Li Kerang(李克让) Chen Ming(陈明) 2001Journal of Donghua University(English Edition)2001,18,3:0
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