根据MODIS数据推断的中国东北森林物候格局

1 IntroductionPhenology is the study ofthe recurring vegetation cycles and theirconnection to the surroundingenvironm ental factors such as clim ate, hydrology, soil, etc. (W an et al., 1987). Phenologicalrecords provide an integrative indication of the s…     

综合地理数据与MODIS物候特征的区域土地覆盖制图(英文)

The study developed a feasible method for large-area land cover mapping with combination of geographical data and phenological characteristics, taking Northeast China (NEC) as the study area. First, with the monthly average of precipitation and temperature datasets, the spatial clustering method was used to divide the NEC into four ecoclimate regions. For each ecoclimate region, geographical variables (annual mean precipitation and temperature, elevation, slope and aspect) were combined with phenological variables derived from the moderate resolution imaging spectroradiometer (MODIS) data (enhanced vegetation index (EVI) and land surface water index (LSWI)), which were taken as input variables of land cover classification. Decision Tree (DT) classifiers were then performed to produce land cover maps for each region. Finally, four resultant land cover maps were mosaicked for the entire NEC (NEC_MODIS), and the land use and land cover data of NEC (NEC_LULC) interpreted from Landsat-TM images was used to evaluate the NEC_MODIS and MODIS land cover product (MODIS_IGBP) in terms of areal and spatial agreement. The results showed that the phenological information derived from EVI and LSWI time series well discriminated land cover classes in NEC, and the overall accuracy was significantly improved by 5.29% with addition of geographical variables. Compared with NEC_LULC for seven aggregation classes, the area errors of NEC_MODIS were much smaller and more stable than that of MODIS_IGBP for most of classes, and the wall-to-wall spatial comparisons at pixel level indicated that NEC_MODIS agreed with NEC_LULC for 71.26% of the NEC, whereas only 62.16% for MODIS_IGBP. The good performance of NEC_MODIS demonstrates that the methodology developed in the study has great potential for timely and detailed land cover mapping in temperate and boreal regions.     

东北三省旅游经济差异的时空特征分析

区域旅游经济差异是旅游业“竞合”关系的主要影响因素之一,利用加权变异系数、基尼系数、锡尔系数等方法,以2002~2012年东北三省的国内旅游收入和旅游外汇收入为分析对象,揭示东北三省区域旅游经济差异的时空特征,以期为优化区域旅游经济结构,避免恶性竞争造成的不利影响提供依据。结果表明：① 东北三省旅游经济省间绝对差异不大,相对差异逐渐增大;② 三省省内各地市的国内旅游收入差异和旅游外汇收入差异都较大,黑龙江省的国内旅游收入差异在扩大,辽宁和吉林在减小;吉林省的旅游外汇收入差异基本保持不变,辽、黑两省在减小;③ 三省的地带间旅游经济差异基本保持不变。     

The dynamic monitoring of corn planting area distribution in response to climate change from 2001 to 2010: a case study of Northeast China

Climate change has effects on crop distribution and production due to altering precipitation and temperature patterns. Northeast China is one of the most sensitive areas affected by climate change. In this study, MODIS09A1 data from MODerate resolution Imaging Spectroradiometer incorporated with phenology data from 21 agro-meteorological stations were used to monitor the dynamic change of corn distribution in response to climate change in the Northeast China for the decade of 2001 and 2010. Corn area estimates and statistics had the same change trend from 2001 to 2010 showing an annual increase. Furthermore, in order to analyse the gravity centre variations of the corn distribution, regions were chosen with corn planting areas of more than 500 km². Results showed that the main corn planting area had a trend to move towards high latitude and high longitude in response to climate change. It moved towards north about .58 degrees and east about .21 degrees between 2001 and 2010. The analysis of temperature and precipitation patterns revealed the same trend as the corn planting area. However, the corn area change was more sensitive to temperature than precipitation in Northeast China.     

东北地区城镇化质量测度及其时空格局特征

采用熵值法确定权重,运用探索性空间数据分析方法对东北地区34个地级及以上城市2008—2018年城镇化质量进行测度并分析其时空格局特征。结果发现：从整体变化趋势来看,东北地区整体的城镇化质量呈现显著提升趋势,但2015—2018年增长曲线呈现出“U”字型波动特征,各子系统中“城市活力”得分呈现显著下降趋势。从时空格局特征来看,东北地区城镇化质量分布的时空分异明显,整体显著提升趋势下部分城市出现“阶段性”下降,通过LISA集聚图分析发现,东北地区城镇化质量的“高值”集聚区域主要分布在“哈长”城市群和辽中南城市群,“低值”集聚区域主要分布在黑龙江省北部地区。     

东北地区制造业空间格局演化及其空气污染环境效应——基于企业数据的实证

基于企业数据与空间计量方法,总结2005年、2010年、2015年和2020年东北地区制造业空间格局演化特征,并在分析地区空气污染同期变化的基础上,探讨制造业空间格局演化对空气污染的环境效应。结果表明：① 东北地区制造业集聚水平逐渐增高,并形成多个新兴“热点区”,31个细分行业大类均呈集聚分布,资本规模由高度集中向“T字形”铁路周边沿线城市扩散。② 东北地区产业结构清洁度与产业技术高级度均呈下降趋势,在县区尺度上体现出空间差异且有不同程度的增幅和降幅。③ 制造业空间格局对空气污染具有显著的集聚效应和技术效应,二者分别表现为拥挤效应和回弹效应,但规模效应和结构效应不明显。     

气候变化和物候变动对东北黑土区农业生产的协同作用及未来粮食生产风险

东北黑土区是中国重要的粮食生产基地,也是中国气候变化最敏感的地区之一。然而,气候变化背景下东北黑土区气候及物候变化对农业生产力的综合影响并不清晰,未来农业生产风险评估的定量化程度不够,风险等级制定缺乏依据。本文借助遥感产品、气候资料和模拟数据等资料,综合运用多元线性回归、相关分析及干旱危险性指数等方法,探究东北黑土区作物物候动态及其气候响应特征,辨识气候与物候变化对农业生产的复合效应及未来可能风险。结果表明：① 2000—2017年东北黑土区29.76%的区域作物生长季开始期呈显著延后趋势,16.71%的区域作物生长季结束期呈提前态势,生长季开始期受气温的影响范围广,且滞后时间长;生长季结束期与前期气候变化关系更加密切,且带状差异性响应格局尤其明显。② 气候变化和物候期改变对作物生产的解释能力较生长季同期气候变化的解释能力增加了70.23%,解释面积扩大了85.04%。③ RCP8.5情景下东北黑土区粮食总产量呈现上升趋势,粮食生产风险表现出“南增北减”的演变特征,风险区面积不断扩大,全球温升2.0 ℃时,松嫩黑土亚区南部粮食减产量可能达到10%。研究有助于深入认识气候—物候—作物生产的关联机理及未来粮食生产风险,对制定气候变化应对策略,保障国家粮食安全具有重要意义。     

东北振兴以来地区经济发展水平演化及空间分异模式

从经济基础、经济增长和经济结构等方面构建了地区经济发展水平的综合评价指标体系,并采用因子分析法和ESDA方法,从地级行政区尺度对东北振兴战略实施以来的经济发展水平、空间格局及演化规律进行研究。研究发现：过去十多年来,东北地区整体经济发展水平取得了一定的成就,但内部发展差异呈扩大趋势,黑龙江省北部成为东北经济发展最薄弱的地区;在空间上,东北经济发展呈现出集聚性,并主要表现为核心-边缘、轴带集聚发展以及沿海-沿边等空间分异模式。     

东北地区城市女性就业水平空间分异机制

促进女性就业,不仅能够提高女性社会经济地位,还有助于提高社会生产力和经济活力。论文以东北三省“五普”“六普”和2015年1%人口抽样调查数据为基础,借助空间自回归模型方法,探讨东北地区城市女性就业水平的时空特征及其驱动机制。结果表明：① 东北地区城市女性就业水平整体较低,其中南部城市的女性就业水平高于北部。② 从影响因素来看,高学历、便捷的交通、较高的工业水平、完整的家庭以及更多的家庭支持对城市女性就业水平具有积极效应;而养育负担对女性就业水平具有负向效应。其中,三代及以上家庭户比例是2000—2015年老工业基地城市女性就业水平空间分异的主导因素,可见,一个完整的家庭对女性就业具有极其重要的作用。     

东北地区乡村性评价及时空分异

以县域为基本空间单元,构建了刻画乡村性的指标体系,定量测度了2000年、2004年、2008年、2012年东北地区149个县域乡村性指数,并采用ESDA空间统计方法,探索东北地区县域乡村性的时空演变特征。结果表明：① 东北地区县域乡村性指数普遍较高,均值呈现波动下降的态势。② 县域乡村性指数呈现南低北高,逐步极化的空间格局,且与其到区域性中心城市的距离成正比,呈现环状递增的空间分布格局。③ 县域乡村性趋于空间集聚,且随时间推移,低值和低值、高值和高值县域的空间集聚增强;冷点、次冷点、热点、次热点区域在空间上均呈现“北上”发展态势,温和区域在空间上呈现“南下”的发展态势。从国家政策、产业结构、农业投入和资本投入等视角,分析了乡村性时空演变的原因。     

基于FORCCHN的未来东北森林生态系统碳储量模拟

以东北森林为研究对象,应用中国森林生态系统碳收支模型FORCCHN,模拟该区森林生态系统碳储量未来可能的时空变化。结果表明: 2003~2049年东北森林生态系统可能仍将具有明显碳汇功能,但强度呈下降趋势;土壤碳储量的变化趋势是从增长到饱和然后逐渐降低的过程,植被碳储量则基本上随时间变化呈逐渐增长趋势。空间上,该区土壤碳储量都有不同程度增加或降低,但植被碳储量都在不同程度的增加;土壤碳储量可能在植被碳储量之前得到饱和,因而东北森林生态系统碳吸收能力的降低主要是由土壤碳储量的减少造成的,而植被碳的增加将会在一定时间内减缓这一过程。     

基于随机森林模型的东北地区收缩城市分布格局及影响因素研究

基于2005-2009年、2010-2014年、2015-2019年和2005-2019年人口变化数据,判定东北地区收缩城市,分析其空间分布格局,并对比运用多元线性回归方法和随机森林回归方法探索东北地区收缩城市形成的影响因素及其影响作用.结果 表明:①空间上,东北地区的收缩城市主要分布在以长白山、三江平原、小兴安岭和大...     

An approach to spatially explicit reconstruction of historical forest in Northeast China

The spatially explicit reconstruction of historical land-cover datasets plays an important role in studying the climatic and ecological effects of land-use and land-cover change（LUCC）. Using potential natural vegetation（PNV） and satellite-based land use data, we determined the possible maximum distribution extent of forest cover in the absence of human disturbance. Subsequently, topography and climate factors were selected to assess the suitability of land for cultivation. Finally, a historical forest area allocation model was devised on the basis of the suitability of land for cultivation. As a case study, we used the historical forest area allocation model to reconstruct forest cover for 1780 and 1940 in Northeast China with a 10-km resolution. To validate the model, we compared satellite-based forest cover data with our reconstruction for 2000. A one-sample t-test of absolute bias showed that the two-tailed significance was 0.12, larger than the significant level 0.05, suggesting that the model has strong ability to capture the spatial distribution of forests. In addition, we calculated the relative difference of our reconstruction at the county scale for 1780 in Northeast China. The number of counties whose relative difference ranged from-30% to 30% is 99, accounting for 74.44% of all counties. These findings demonstrated that the provincial forest area could be transformed into forest cover maps well using the model.     

森林生态系统健康评价指标及其在中国的应用

根据1995～1998年的遥感资料、1980～1997年全国气象资料以及1949～2001年的森林统计资料以及全国300多个森林样地调查资料，在生态系统健康理论基础上，以活力(V)、组织结构(D)和恢复力（R)为评价指标，对中国森林生态系统的健康状况进行了评价，并对中国森林生态系统健康的空间格局进行了分析。我国森林生态系统健康指数高的区域主要分布在热带雨林季雨林以及天然林分布的区域，而蒙新林区和暖温带林区的健康指数较低，且由南到北逐渐降低。温度和降水对森林生态系统健康的空间格局有较大的影响。通过生态系统健康指数与活力、组织结构和抵抗力的相关分析可知，抵抗力对生态系统健康影响最大，其次是组织结构，影响力最小的是活力。     

近30年中国东北地区玉米种植体系的时空动态分析(英文)

Understanding crop patterns and their changes on regional scale is a critical requirement for projecting agro-ecosystem dynamics. However, tools and methods for mapping the distribution of crop area and yield are still lacking. Based on the cross-entropy theory, a spatial production allocation model(SPAM) has been developed for presenting spatio-temporal dynamics of maize cropping system in Northeast China during 1980–2010. The simulated results indicated that(1) maize sown area expanded northwards to 48°N before 2000, after that the increased sown area mainly occurred in the central and southern parts of Northeast China. Meanwhile, maize also expanded eastwards to 127°E and lower elevation(less than 100 m) as well as higher elevation(mainly distributed between 200 m and 350 m);(2) maize yield has been greatly promoted for most planted area of Northeast China, especially in the planted zone between 42°N and 48°N, while the yield increase was relatively homogeneous without obvious longitudinal variations for whole region;(3) maize planting density increased gradually to a moderately high level over the investigated period, which reflected the trend of aggregation of maize cultivation driven by market demand.     

中国东北三省对外贸易空间格局研究

分析了东北三省整体的对外贸易规模及贸易伙伴,在此基础上,分别从省级和地市级尺度比较研究了东北三省内部对外贸易空间格局,以及东北三省在不同贸易空间方向上的商品结构。研究结果表明：① 东北三省与东南亚、中东等地区贸易规模有所增长,但日韩、德国、美国和俄罗斯等依然是其主要的贸易伙伴;② 东北三省对外贸易的商品多为原材料、初级加工品和劳动密集型产品等,且商品结构趋同明显,不利于发挥地区的比较优势;③ 大城市和沿海港口城市是东北三省对外贸易重要的空间载体。根据东北三省及各自的对外贸易现状和面临的挑战,提出了差异化的进出口贸易空间格局优化策略。     

森林生态系统健康评价指标在中国的应用

1IntroductionDuring recent two decades, the idea of "health" as an appropriate paradigm to assess the condition of ecosystems, is watchword of contemporary ecosystem management. The phrase "forest ecosystem health" has been used with increasing frequency in the context of forestry and natural resource management. Many scientists give the definitions from socio-economic and ecological perspectives (Rapport, 1992; USDA Forest Service, 1993; O'Laughlin, 1996; Allen, 2001). Forest health is a …     

Forest ecosystem health assessment and analysis in China

Based on more than 300 forest sample plots surveying data and forestry statistical data, remote sensing information from the NOAA AVHRR database and the daily meteorological data of 300 stations, we selected vigor, organization and resilience as the indicators to assess large-scale forest ecosystem health in China and analyzed the spatial pattern of forest ecosystem health and influencing factors. The results of assessment indicated that the spatial pattern of forest ecosystem health showed a decreasing trend along latitude gradients and longitude gradients. The healthy forests are mainly distributed in natural forests, tropical rainforests and seasonal rainforests; secondarily orderly in northeast national forest zone, subtropical forest zonation and southwest forest zonation; while the unhealthy forests were mainly located in warm temperate zone and Xinjiang-Mongolia forest zone. The coefficient of correction between Forest Ecosystem Health Index (FEHI) and annual average precipitation was 0.58 (p<0.01), while the coefficient of correlation between FEHI and annual mean temperatures was 0.49 (p<0.01), which identified that the precipitation and temperatures affect the pattern of FEHI, and the precipitation's effect was stronger than the temperature's. We also measured the correlation coefficient between FEHI and NPP, biodiversity and resistance, which were 0.64, 0.76 and 0.81 (p<0.01) respectively. The order of effect on forest ecosystem health was vigor, organization and resistance.     

东北地区土地利用多功能性演化的时空格局

土地利用多功能性是根据社会经济目标进行土地利用的过程,是确保社会经济与生态环境协调发展的关键。本文通过构建“社会—经济—生态”三维土地利用多功能性评价指标体系,对1990-2013年东北地区土地利用多功能性进行综合评价,旨在阐释其土地利用多功能性演化的时空格局。研究表明：1990-2013年东北地区土地利用功能值均呈现上升态势但增速有所差异,黑龙江、吉林、辽宁土地利用功能发展程度依次递增,其年均增长率分别为2.976%、2.725%、2.261%;黑龙江和吉林社会功能值呈现波动性增长,辽宁则表现为阶段性变化;黑龙江经济系统功能值逐渐增大,而吉林和辽宁经济功能值总体呈现上升趋势,但在2000-2005年有所波动;黑龙江与吉林生态系统功能值呈现由基本稳定转变为波动增长的趋势,而辽宁则始终具有较大波动性;经济功能中的土地的生产功能与交通功能对东北地区省域土地利用功能均有较大影响,经济和社会因素对黑龙江与吉林土地利用功能多样性影响较大,生态因素则对其影响较小,而经济、社会和生态因素对辽宁土地利用功能均有较大影响。     

高铁网络化下东北地区旅游空间结构动态演变分析

运用GIS空间分析方法测度高铁对东北城市旅游交通可达性的影响,进而分析高铁网络化下东北城市旅游市场出现的新特征、新变化。研究发现：① 高铁极大提升了东北城市旅游交通可达性整体水平,可达性空间格局呈现明显的“高铁廊道效应”。网络化形成进程中,可达性空间格局变化由主干道运行期的“极化特征”向支线完善期的“均衡特征”转变,东北“全域式旅游”发展格局开始形成;② 主干道形成期,高铁以“虹吸效应”为主导,加剧了东北旅游市场发展的不均衡,促进哈大旅游经济带形成;支线完善期,高铁以“扩散效应”为主导,均衡式发展格局开始凸显;③ 高铁推动了东北城市“同城化”发展进程,市内游、周边游模式将发生改变,省际游、跨地区游模式将逐步盛行。