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| 1 | Accuracy assessment of global historical cropland datasets based on regional reconstructed historical data——A case study in Northeast China显示文摘Historical cropland datasets are fundamental for quantifying the effects of human land use activities on climatic change and the carbon cycle. Two representative global land-use datasets, the Global Land Use Database (termed SAGE dataset) and the Historical Database of the Global Environment (termed HYDE dataset) have been established and used widely. Despite improvement of data quality and methodologies for extracting historical land use information, certain dataset limitations exist that need to be quantified and communicated to users so that they can make informed decisions on whether and how these land-use products should be used. The Cropland data of Northeast China (CNEC) is based on calibrated historical data and a multi-sourced data conversion model, and reconstructs cropland cover change in Northeast China over the last 300 years. Us- ing the CNEC as a reference, we evaluated the accuracy of cropland cover for SAGE and HYDE in Northeast China at spatial scales ranging from the entire Northeast China to provinces and even individual raster grid cells. Neither SAGE nor HYDE reflects real historical land reclamation. Cropland areas in SAGE are overestimated by 20.98 times in 1700 to 1.6 times in 1990. Although HYDE is better, there are significant disagreements in cropland area and distribution between HYDE and CNEC, especially in the 18th and 19th centuries. The proportion of total grid cells whose relative error was greater than 100% was 63.55% in 1700 and 53.27% in 1780. Global cropland dataset errors over Northeast China originate mainly from both the reverse calculation method for historical cropland data based on modern spatial patterns, and modern land-use outputs from satellite data. | Li BeiBei Fang XiuQi Ye Yu Zhang XueZhen | 2010 | Science China Earth Sciences2010，53，11： | 31 |
| 2 | Comparisons of cropland area from multiple datasets over the past 300 years in the traditional cultivated region of China显示文摘陆地使用 / 盖住变化是在气候和生态的模拟的一个重要参数。尽管他们广泛地在社区,半自动地面防空系统数据集和 HYDE 数据集被使用了,二代表性的全球历史的陆地使用数据集,很少在地区性的规模关于他们的精确性被估计。这里,我们为中国(TCRC ) 的传统的栽培区域执行了一些评价在上持续 300 年,由把 SAGE2010 和 HYDE (v3.1 ) 与中国历史的农田数据集(CHCD ) 作比较。比较在三空间规模被执行:由 60 km 格子房间的全部学习区域,省的区域和 60 km。结果证明(1 ) 从 SAGE2010 的农田区域从 CHCD 是多于那的大部分;而且,以在 1950 以后的从 1700 ~ 1950 和 0.34% 的 0.51% 的率的生长从 CHCD 与那也不一致。(2 ) HYDE 数据集(v3.1 ) 在全部学习区域上比半自动地面防空系统数据集接近了 CHCD 数据集。然而,大偏爱能被 60 km 格子房间规模在省的规模和 60 km 检测。有比70%大的偏爱的格子房间的百分比(<-70%或>70%)并且90%(<-90%或>90%)当那些有的偏爱为仅仅5%6%从10%~10%并且从30%~30%报道 时,分别地说明了全部的格子房间的56%63%和40%45%并且17%全部的格子房间分别地。(3 ) 用本地历史的档案,有高精确性的历史的数据集将是改进气候和生态的模拟的精确性的一个珍贵方法重建。 | HE Fanneng LI Shicheng ZHANG Xuezhen GE Quansheng DAI Junhu | 2013 | Journal of Geographical Sciences2013，23，6： | 21 |
| 3 | Cropland cover change in Northeast China during the past 300 years显示文摘Land use/cover change induced by human activities has emerged as a 'global' phenomenon with Earth system consequences. Northeast China is an area where the largest land cultivation activities by migrants have happened in China during the past 300 years. In this paper, methods including documentary data calibration and multi-sourced data conversion model are used to reconstruct historical cropland cover change in Northeast China during the past 300 years. It is concluded that human beings have remarkably changed the natural landscape of the region by land cultivation in the past 300 years. Cropland area has increased almost exponentially during the past 300 years, especially during the past 100 years when the ratio of cropland cover changed from 10% to 20%. Until the middle of the 19th century, the agricultural area was still mainly restricted in Liaoning Province. From the late 19th century to the early 20th century, dramatic changes took place when the northern boundary of cultivation had extended to the middle of Heilongjiang Province. During the 20th century, three agricultural regions with high ratio of cropland cover were formed after the two phases of spatial expansion of cropland area in 1900s—1930s and 1950s—1980s. Since 1930s—1940s, the expansion of new cultivated area have invaded the forest lands especially in Jilin and Heilongjiang Provinces. | YE Yu FANG XiuQi REN YuYu ZHANG XueZhen CHEN Li | 2009 | Science China Earth Sciences2009，52，8： | 21 |
| 4 | Rates of temperature change in China during the past 2000 years显示文摘Using 24 proxy temperature series,the rates of temperature change in China are analyzed at the 30-to 100-year scales for the past 2000 years and at the 10-year scale for the past 500 years.The results show that,at the 100-year scale,the warming rate for the whole of China in the 20th century was only 0.6±1.6°C/100 a (interval at the 95% confidence level,which is used hereafter),while the peak warming rate for the period from the Little Ice Age (LIA) to the 20th century reached 1.1±1.2°C/100 a,which was the greatest in the past 500 years and probably the past 2000 years.At the 30-year scale,warming in the 20th century was quite notable,but the peak rate was still less than rates for previous periods,such as the rapid warming from the LIA to the 20th century and from the 270s-290s to 300s-320s.At the 10-year scale,the warming in the late 20th century was very evident,but it might not be unusual in the context of warming over the past 500 years.The exact timing,duration and magnitude of the warming peaks varied from region to region at all scales.The peak rates of the 100-year scale warming in the AD 180s-350s in northeastern China as well as those in the 260s-410s and 500s-660s in Tibet were all greater than those from the mid-19th to 20th century.Meanwhile,the rates of the most rapid cooling at scales of 30 to 100 years in the LIA were prominent,but they were also not unprecedented in the last 2000 years.At the 10-year scale,for the whole of China,the most rapid decadal cooling in the 20th century was from the 1940s to 1950s with a rate of 0.3±0.6°C/10 a,which was similar to rates for periods before the 20th century.For all regions,the rates of most rapid cooling in the 20th century were all less than those for previous periods. | GE QuanSheng ZHANG XueZhen HAO ZhiXin ZHENG JingYun | 2011 | Science China Earth Sciences2011，54，11： | 17 |
| 5 | Agriculture Development-induced Surface Albedo Changes and Climatic Implications Across Northeastern China显示文摘To improve the understandings on regional climatic effects of past human-induced land cover changes,the surface albedo changes caused by conversions from natural vegetation to cropland were estimated across northeastern China over the last 300 years,and its climatic effects were simulated by using the Weather Research and Forecasting (WRF) model.Essential natural vegetation records compiled from historical documents and regional optimal surface albedo dataset were used.The results show that the surface albedo decreased by 0.01-0.03 due to conversions from grassland to cropland in the Northeast China Plain and it increased by 0.005-0.015 due to conversions from forests to cropland in the surrounding mountains.As a consequence,in the Northeast China Plain,the surface net radiation increased by 4-8 W/m 2,2-5 W/m 2,and 1-3 W/m 2,and the climate was therefore warmed by 0.1℃-0.2℃、0.1℃-0.2℃、 0.1℃-0.3 ℃ in the spring,autumn and winter,respectively.In the surrounding mountain area,the net radiation decreased by less than 1.5 W/m 2,and the climate was therefore cooled too slight to be detected.In summer,effects of surface albedo changes on climate were closely associated with moisture dynamics,such as evapotranspiration and cloud,instead of being merely determined by surface radiation budget.The simulated summer climatic effects have large uncertainties.These findings demonstrate that surface albedo changes resulted in warming climate effects in the non-rainy seasons in Northeast China Plain through surface radiation processes while the climatic effects in summer could hardly be concluded so far. | ZHANG Xuezhen WANG Wei-Chyung FANG Xiuqi YE Yu ZHENG Jingyun | 2012 | Chinese Geographical Science2012，22，3： | 15 |
| 6 | Mapping Heterotic Loci for Yield and Agronomic Traits Using Chromosome Segment Introgression Lines in Cotton显示文摘在现在的学习,一套染色体片断基因渗入排队(CSIL ) 使用 Gossypium hirsutum L。TM-1 作为接受者父母和 G。施主父母被用来为种间的混血儿探索杂种优势的基因基础的 barbadense Hai7124。个别地从与两个父母一起交叉的 CSIL 导出的 F1 人口的二个集合被设置调查 heterotic loci (HL ) 和替换效果 loci (SL ) 。58 HL 和 39 SL 的一个总数在 3 年里被识别。一稳定的 HL, hLP-A4-3,能在所有 3 年里被检测。三 HL, hBS-A8-1, hLP-D6-1,和 hSI-D7-11,能在 2 年里被检测。四 SL, sBS-D7-1, sLP-A8-1, sLP-D7-1,和 sLP-D12-1,能在 2 年里被检测。HL 和 SL 趋于在有靠近的位置的一些 HL 富有的染色体片断分布式。与在以前的研究检测的 QTL 相比, HL 与 QTL 显示出很少重叠,显示特点显型和杂种优势可能被 loci 的不同集合控制。基因效果的所有三种形式(部分 -- ,完整 -- ,在主导上) 被识别,当在主导上的效果做了主要贡献到杂种优势时。这些结果可以帮助为在棉花澄清杂种优势的遗传机制打了基础。 | Xian Guo Yuping Guo Jun Ma Fang Wang Mizhen Sun Lijuan Gui Jiajia Zhou Xianliang Song Xuezhen Sun Tianzhen Zhang | 2013 | Journal of Integrative Plant Biology2013，55，8： | 13 |
| 7 | Reconstructing temperature change in Central East China during 601-920 AD显示文摘Using historical records on first and last frost and snow,spring cultivation,David peach blossom,autumn crop harvest,grade of sea freeze and change in northern citrus boundary,we reconstructed temperature change during 601-920 AD.The mean temperature of the winter half-year(October to April)over Central East China during this period was about-0.22°C higher than that of the present(1961-2000 AD mean).During 601-820 AD,mean temperature was about-0.52°C higher than the present.During 821-920 AD,the mean temperature was 0.42°C lower than the present.The temperature fluctuations were characterized by a maximum amplitude of 1.05°C at the centennial scale,1.38°C at the 50-year scale,2.02°C at the 30-year scale,and 2.3°C at the 20-year scale.There were four peaks warmer than today(601-620 AD,mean of 1°C higher temperature;641-660 AD,1.44°C;701-720 AD,0.88°C;781-800 AD,0.65°C).Three cold periods were in 741-760,821-840,and 881-900 AD,the mean temperature of which was 0.37-0.87°C lower than the present. | GE QuanSheng LIU HaoLong ZHENG JingYun ZHANG XueZhen | 2010 | Chinese Science Bulletin2010，55，34： | 8 |
| 8 | 1876-1878 severe drought in North China:Facts,impacts and climatic background显示文摘Based on the reconstructed precipitation series in North China from historical documents, the 1876-1878 drought was identified as the most severe and extreme one in North China over the past 300 years. Meanwhile, the spatial patterns of seasonal and annual precipitation during 1876-1877 were analyzed and the social and economic impacts related with this drought event were evaluated according to the descriptions in the historical documents. The results indicated that this long-lasting drought started by the spring of 1876 and did not stop until the spring of 1878. Within the three years, the harvest failures brought the rice price increased to 5-10 times than that in the normal year, and the total population in the five provinces over North China decreased by more than 20 million due to a large number of dead people and migrations. In addition, related investigations suggested that the 1876-1878 drought was prevalent worldwide, which has possible link with abnormal high SST in the equatorial central and eastern Pacific, strong El Nio episode and positive AAO anomalies. | HAO ZhiXin ZHENG JingYun WU GuoFeng ZHANG XueZhen GE QuanSheng | 2010 | Chinese Science Bulletin2010，55，26： | 8 |
| 9 | Carbon emissions induced by cropland expansion in Northeast China during the past 300 years显示文摘Assessments of the impacts of land use and land cover changes(LUCC) on the terrestrial carbon budget, atmospheric CO2 concentration, and CO2-related climatic change are important to understand the environmental effects of LUCC and provide information about the effects of historical carbon emissions. Using regional land cover reconstructions from historical records, with a bookkeeping model, we estimated the carbon sink changes caused by historical cropland expansion in Northeast China during the past 300 years. The conclusions are as follows:(1) There was a dramatic land reclamation of cropland during the past 300 years in Northeast China. Approximately 26% of the natural land was cultivated, and 38% of the grassland and 20% of the forest and shrubland were converted to cropland.(2) The carbon emission induced by cropland expansion between 1683 and 1980 was 1.06–2.55 Pg C, and the estimation from the moderate scenario was 1.45 Pg C. The carbon emissions of the soil carbon pool was larger than that from the vegetation carbon pool and comprised more than 2/3 of the total carbon emissions.(3) The carbon emissions of the three provinces in Northeast China were different. Heilongjiang Province had the largest carbon emissions, and Jilin Province had the second largest emissions.(4) The primary source of carbon emissions was forest reclamation(taking 60% of the total emissions in the moderate scenario), the secondary source was grassland cultivation(taking 27%), and the tertiary sources were shrubland and wetland reclamation(taking 13%). Examination on the data accuracy revealed that the high-resolution regional land cover data allowed the carbon budget to be evaluated at the county level and improved the precision of the results. The carbon emission estimation in this study was lower than those in previous studies because of the improved land use data quality and various types of land use change considered. | LI BeiBei FANG XiuQi YE Yu ZHANG XueZhen | 2014 | Science China Earth Sciences2014，57，9： | 8 |
| 10 | Reconstruction of cropland area and spatial distribution in the mid-Northern Song Dynasty (AD1004-1085)显示文摘为了理解历史的导致人的土地,盖住变化和它的气候的效果,与明确的空间信息创造历史的陆地使用数据集是必要的。用税农田区域和从历史的文件编的家庭的数字,我们在每陆(在北歌王朝的一个省级的政治区域) 以内估计了真实农田区域和人口在中间 -- 北歌王朝(AD1004-1085 ) 。评价通过分析税,人口和农业开发的当代的政策被完成。然后,我们把政治基于区域的农田区域变换成地理上明确的格子在由 60 km 的 60 km 的房间尺寸的基于房间的部分农田。变换作为独立变量用地志的斜坡,高度和人口密度基于每个格子房间的精明的耕作适用性。作为结果,在在 1070 年代的北歌领土以内的农田的全部的区域被估计是大约 7.2 亿亩(中国区域单位, 1 亩 = 666.7 m2 ) ,哪个 40.1% 和 59.9% 分别地发生在北方和南方。人口被估计是大约 8720 万,哪个 38.7% 和 61.3% 分别地在北方和南方,并且人均的农田区域是大约 8.2 亩。国家吝啬的开垦比率(即到全部的土地的农田区域的比率区域;RRA 此后为短) 是一回 16.6% 。平凡区域例如诺思中国平原,中间和长江的更低的活动范围, Guanzhong 平原,包围东廷·莱克和波伊昂·莱克和四川盆的平原,有更高的 RRA,主要是超过 40% ;当时多山、多山的区域例如 Nanling 山的南方,西南区域(排除 Chengdu 平原) ,黄土高原和东南沿海的区域,有更低的 RRA,是不到 20% 。而且, RRA 与地志的斜坡和高度变化了。在低高度(250 m ) 的区域,中间的高度(250100 m ) 和高高度(10003500 m ) ,有 4.43 亿, 2.15 亿并且 6400 万亩农田分别地并且他们的地区性的吝啬的 RRA 分别地是 27.5% , 12.6% 和 7.2% 。在扁平的斜坡,轻轻的斜坡,中等斜坡和陡峭的斜坡的区域,有 1.16 亿, 4.56 亿, 1.44 亿并且 200 万亩农田分别地并且他们的地区性的吝啬的 RRA 分别地是 34.6% , 20.7% , 8.5% 和 2.3% 。 | HE Fanneng LI Shicheng ZHANG Xuezhen | 2012 | Journal of Geographical Sciences2012，22，2： | 7 |
| 11 | Variation in vegetation greenness in spring across eastern China during 1982-2006显示文摘Vegetation greenness is a key indicator of terrestrial vegetation activity. To under-stand the variation in vegetation activity in spring across eastern China (EC), we analysed the variation in the Normalised Difference Vegetation Index (NDVI) from April to May during 1982-2006. The regional mean NDVI across EC increased at the rate of 0.02/10yr (r2=0.28; p=0.024) prior to 1998; the increase ceased, and the NDVI dropped to a low level thereafter. However, the processes of variation in the NDVI were different from one region to another. In the North China Plain, a cultivated area, the NDVI increased (0.03/10yr; r2=0.52; p<0.001) from 1982 to 2006. In contrast, the NDVI decreased (-0.02/10yr; r2=0.24; p=0.014) consecu-tively from 1982 to 2006 in the Yangtze River and Pearl River deltas, two regions of rapid urbanisation. In the eastern region of the Inner Mongolian Plateau and the lower reaches of the Yangtze River in East China, the NDVI increased prior to 1998 and decreased thereafter. In the Hulun Buir area and the southern part of the Yangtze River Basin, the NDVI increased prior to 1998 and remained static thereafter. The NDVI in the grasslands and croplands in the semi-humid and semi-arid areas showed a significant positive correlation with precipitation, while the NDVI in the woodlands in the humid to semi-humid areas showed a significant positive correlation with temperature. As much as 60% of the variation in the NDVI was ex-plained by either precipitation or temperature. | ZHANG Xuezhen DAI Junhu GE Quansheng | 2013 | Journal of Geographical Sciences2013，23，1： | 6 |
| 12 | Observed,Reconstructed,and Simulated Decadal Variability of Summer Precipitation over Eastern China显示文摘Based on observations made during recent decades, reconstructed precipitation for the period A.D. 1736–2000,dry–wet index data for A.D. 500–2000, and a 1000-yr control simulation using the Community Earth System Model with fixed pre-industrial external forcing, the decadal variability of summer precipitation over eastern China is studied. Power spectrum analysis shows that the dominant cycles for the decadal variation of summer precipitation are:22–24 and quasi-70 yr over the North China Plain; 32–36, 44–48, and quasi-70 yr in the Jiang–Huai area; and 32–36and 44–48 yr in the Jiang–Nan area. Bandpass decomposition from observation, reconstruction, and simulation reveals that the variability of summer precipitation over the North China Plain, Jiang–Huai area, and Jiang–Nan area, at scales of 20–35, 35–50, and 50–80 yr, is not consistent across the entire millennium. We also find that the warm(cold) phase of the Pacific Decadal Oscillation generally corresponds to dry(wet) conditions over the North China Plain, but wet(dry) conditions in the Jiang–Nan area, from A.D. 1800, when the PDO became strengthened.However, such a correspondence does not exist throughout the entire last millennium. Data–model comparison suggests that these decadal oscillations and their temporal evolution over eastern China, including the decadal shifts in the spatial pattern of the precipitation anomaly observed in the late 1970s, early 1990s, and early 2000s, might result from internal variability of the climate system. | Jingyun ZHENG Maowei WU Quansheng GE Zhixin HAO Xuezhen ZHANG | 2017 | Journal of Meteorological Research2017，31，1： | 6 |
| 13 | Using MaxEnt Model to Guide Marsh Conservation in the Nenjiang River Basin, Northeast China显示文摘Incorporating private and working lands into protected area networks could mitigate the isolation state of protected areas(PAs) and improve the efficiency of conservation.But how to select patches of land for conservation is still a troublesome issue.In this study, the MaxEnt model and irreplaceability index were applied to guide marsh conservation in the Nenjiang River Basin, Northeast China.According to the high accuracy of the MaxEnt model predictions(i.e., the average AUC value = 0.933), the Wuyuer River and Zhalong marshes in the downstream reaches of Wuyuer River are the optimal habitat for the Red-crowned crane and migratory waterfowls.There are 22 marsh patches selected by the patch irreplaceability index for conservation, of which 12 patches had been included in the current network of protected areas.The other 10 patches of marsh(amounting to 1096 km^2) far from human disturbances with high NDVI(up to 0.8) and close distance to water(less than 100 m), which are excluded from the existing network of PAs, should be implemented conservation easement programs to improve the protection efficiency of conservation.Specifically, the marshes at Taha, Tangchi, and Lamadian should be given priority for conservation and restoration to reintroduce migratory waterfowls, as this would lessen the current isolation state of the Zhalong National Nature Reserve. | WANG Zhiliang ZHANG Bai ZHANG Xuezhen Tian Hongxu | 2019 | Chinese Geographical Science2019，29，6： | 5 |
| 14 | Spatially precise reconstruction of cropland areas in Heilongjiang Province, northeast China during 1900-1910显示文摘It is necessary to reconstruct past changes in land use and land cover to understand the historical effects of humans on climate and the local environment. We collected information from historical documents on the cropland area at the county level for Heilongjiang Province, northeast China during 1900–1910. The original records from different historical documents were calibrated with each other. We then defined an agricultural suitability index quantified by the distance from settlements, the slope and complexity of the topography, and the distance from rivers. Following the order of the agricultural suitability index from high to low values, the documented areas of cropland at the county level were then allocated into 1 km×1 km cells. The area of cropland in 2009 was then retrieved from Landsat ETM+ images and compared with the areas of cropland during 1900–1910 to determine the human-induced changes in land use and land cover. In this period, the total area of cropland was about 25,397 km2 and this mainly occurred in the mid-southern part of Heilongjiang, in particular the six counties of Hailun, Bayan, Wuchang, Hulan, Shuangcheng and Wangkui. In 2009, the total area of cropland had increased to about 163,808 km2 and had spread over the southwestern part to the central and northeastern parts of Heilongjiang. The area of cropland had therefore increased by about 138,411 km2 during the 20 th century. The proportion of land used as cropland increased from about 5.6% during 1900–1910 to about 36.2% in 2009, indicating that about 30.6% of the natural land surface in Heilongjiang was replaced by cropland. A total of about 44%(60,962 km2) of the cropland was converted from forest, mainly on the western edge and in the northeastern part of the present-day agricultural area. These areas of cropland reconstructed from historical records for the period 1900–1910 could be used as a basic data set to study the effects of agricultural development on climate and the local environment. | ZHANG Lijuan JIANG Lanqi ZHANG Xuezhen | 2015 | Journal of Geographical Sciences2015，25，5： | 4 |
| 15 | Progress of Jinping Underground laboratory for Nuclear Astrophysics(JUNA)显示文摘Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. | WeiPing Liu ZhiHong Li JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou | 2016 | Science China(Physics,Mechanics & Astronomy)2016，59，4： | 3 |
| 16 | Reconstruction of cropland spatial patterns and its spatiotemporal changes over the 20th century on the Songnen Plain, Northeast China显示文摘We initially estimated the cropland area at county level using local historical documents for the Songnen Plain(SNP)in the 1910s and 1930s.We then allocated this cropland area to grid cells with a size of 1 km×1 km,using a range of cultivation possibilities from high to low;this was based on topography and minimum distances to rivers,settlements,and traffic lines.Cropland areas for the 1950s were obtained from the Land Use Map of Northeast China,and map vectorization was performed with Arc GIS technology.Cropland areas for the1970s,1980s,1990s,2000s,and 2010s were retrieved from Landsat images.We found that the cropland areas were 4.92×104 km^2 and 7.60×10~4 km^2,accounting for 22.8%and 35.2% of the total area of the SNP in the 1910s and 1930s,respectively,which increased to 13.14×10~4 km^2,accounting for 60.9%in the 2010s.The cropland increased at a rate of 1.18×10~4km^2 per decade from the 1910s to 1970s while it was merely 0.285×10~4 km^2 per decade from the 1970s to 2010s.From the 1910s to 1930s,new cultivation mainly occurred in the central SNP while,from the 1930s to 1970s,it was mainly over the western and northern parts.This spatially explicit reconstruction could be offered as primary data for studying the effects of changes in human-induced land cover based on climate change over the last century. | ZHANG Lijuan JIANG Lanqi ZHANG Xuezhen | 2017 | Journal of Geographical Sciences2017，27，10： | 3 |
| 17 | 普通玉米、糯玉米和蒸汽压片玉米对生长猪能量和营养物质消化率的影响显示文摘研究的目的是通过饲喂生长猪普通玉米、糯玉米和蒸汽压片玉米来测定其消化能、代谢能和营养物质的表观消化率。 | 朱秋凤 张永静 温春雨 徐作鹏 Dongli Ma Juntao Li Chengfei Huang Fengjuan Yang Yi Wu Ling Liu Wei Jiang Zhicheng Jia Peijun Zhang Xuezhen Liu Shuai Zhang | 2021 | 猪业科学2021，38，3： | 3 |
| 18 | Aberrant cholesterol metabolic signaling impairs antitumor immunosurveillance through natural killer T cell dysfunction in obese liver显示文摘Obesity is a major risk factor for cancers including hepatocellular carcinoma(HCC)that develops from a background of non-alcoholic fatty liver disease(NAFLD).Hypercholesterolemia is a common comorbidity of obesity.Although cholesterol biosynthesis mainly occurs in the liver,its role in HCC development of obese people remains obscure.Using high-fat high-carbohydrate diet-associated orthotopic and spontaneous NAFLD-HCC mouse models,we found that hepatic cholesterol accumulation in obesity selectively suppressed natural killer T(NKT)cell-mediated antitumor immunosurveillance.Transcriptome analysis of human liver revealed aberrant cholesterol metabolism and NKT cell dysfunction in NAFLD patients.Notably,cholesterol-lowering rosuvastatin restored NKT expansion and cytotoxicity to prevent obesogenic diet-promoted HCC development.Moreover,suppression of hepatic cholesterol biosynthesis by a mammalian target of rapamycin(mTOR)inhibitor vistusertib preceded tumor regression,which was abolished by NKT inactivation but not CD8^(+)T cell depletion.Mechanistically,sterol regulatory element-binding protein 2(SREBP2)-driven excessive cholesterol production from hepatocytes induced lipid peroxide accumulation and deficient cytotoxicity in NKT cells,which were supported by findings in people with obesity,NAFLD and NAFLD-HCC.This study highlights mTORC1/SREBP2/cholesterol-mediated NKT dysfunction in the tumor-promoting NAFLD liver microenvironment,providing intervention strategies that invigorating NKT cells to control HCC in the obesity epidemic. | Wenshu Tang Jingying Zhou Weiqin Yang Yu Feng Haoran Wu Myth T.S.Mok Lingyun Zhang Zhixian Liang Xiaoyu Liu Zhewen Xiong Xuezhen Zeng Jing Wang Jiahuan Lu Jingqing Li Hanyong Sun Xiaoyu Tian Philip Chun Yeung Yong Hou Heung Man Lee Candice C.H.Lam Howard H.W.Leung Anthony W.H.Chan Ka Fai To John Wong Paul B.S.Lai Kelvin K.C.Ng Simon K.H.Wong Vincent W.S.Wong Alice P.S.Kong Joseph J.Y.Sung Alfred S.L.Cheng | 2022 | Cellular & Molecular Immunology2022，19，7： | 3 |
| 19 | Evaluation of multidecadal and longer-term temperature changes since 850 CE based on Northern Hemisphere proxy-based reconstructions and model simulations显示文摘The temperature variability over multidecadal and longer timescales(e.g., the cold epochs in the late 15 th, 17 th, and early 19 th centuries) is significant and dominant in the millennium-long, large-scale reconstructions and model simulations;however, their temporal patterns in the reconstructed and simulated temperature series are not well understood and require a detailed assessment and comparison. Here, we compare the reconstructed and simulated temperature series for the Northern Hemisphere(NH) at multidecadal and longer-term timescales(>30 years) by evaluating their covariance, climate sensitivity and amplitude of temperature changes. We found that covariances between different reconstructions or between reconstructions and simulations are generally high for the whole period of 850–1999 CE, due to their similar long-term temporal patterns. However,covariances between different reconstructions or between reconstructions and simulations steadily decline as time series extends further back in time, becoming particularly small during Medieval times. This is related to the large uncetainties in the reconstructions caused by the decreased number of proxy records and sample duplication during the pre-instrumental periods.Reconstructions based solely on tree-ring data show higher skill than multiproxy reconstructions in capturing the amplitude of volcanic cooling simulated by models. Meanwhile, climate models have a shorter recovery(i.e., lag) in response to the cooling caused by volcanic eruptions and solar activity minima, implying the lack of some important feedback mechanisms between external forcing and internal climate processes in climate models. Amplitudes of temperature variations in the latest published tree-ring reconstructions are comparable to those of the multiproxy reconstructions. We found that the temperature difference between the Medieval Climate Anomaly(950–1250 CE) and the Little Ice Age(1450–1850 CE) is generally larger in proxybased reconstructions than in model simulations, but the reason is unclear. | Jianglin WANG Bao YANG Jingyun ZHENG Xuezhen ZHANG Zhiyuan WANG Miao FANG Feng SHI Jingjing LIU | 2020 | Science China Earth Sciences2020，63，8： | 3 |
| 20 | An approach to spatially explicit reconstruction of historical forest in Northeast China显示文摘历史的陆地封面数据集的空间地明确的重建在学习陆地使用和陆地封面变化(LUCC ) 的气候、生态的效果起一个重要作用。用潜在的自然植被(PNV ) 和基于卫星的陆地使用数据,我们当人的骚乱不在时决定了森林盖子的可能的最大的分发程度。随后,地形学和气候因素被选择为耕作估计土地的适用性。最后,一个历史的森林区域分配模型为耕作根据土地的适用性被设计。作为案例研究,我们使用了历史的森林区域分配模型重建在有一个 10-km 决定的东北中国的为 1780 和 1940 的森林盖子。验证模型,我们为 2000 把基于卫星的森林盖子数据与我们的重建作比较。绝对偏爱的一个样品 t 测试证明二尾巴的意义是 0.12,比重要水平大 0.05,建议模型有强壮的能力捕获森林的空间分发。另外,我们在东北中国为 1780 在县规模计算了我们的重建的相对差别。差别其亲戚从 30% ~ 30%的县的数字是 99,为 74.44% 所有县的财务。这些调查结果证明省的森林区域能用模型被转变成森林盖子地图很好。 | LI Shicheng HE Fanneng ZHANG Xuezhen | 2014 | Journal of Geographical Sciences2014，24，6： | 2 |
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