黑龙江省在过去几十年是全球范围内经历人类活动强度最高的区域之一，尤其是农业的发展导致了剧烈的土地利用/土地覆盖变化（Land Use and Land Cover Change，LUCC）。LUCC对区域气候要素及地表和大气之间的相互作用产生重要影响，进而改变了区域气温的分布格局。气温的空间格局和长期变化过程对植被生长产生影响，对改变LUCC格局产生一定的作用。研究农业扩张下LUCC和气温变化的关系，对农业发展规划的制定有指导意义。本文以黑龙江省为基本研究区域，基于农业扩张程度，对黑龙江省的农业发展时期进行划分；利用GIS的地学统计模块模拟了生长季（5-9月）气温的空间格局，并运用经验正交函数（Empirical Orthogonal Function，EOF）提取了33年间生长季气温的时空变化结构；在此基础上选择三江平原挠力河流域典型农区为研究区域，通过重心模型分析了LUCC对农业扩张和气候变化的响应，并利用中尺度气象模式（Mesoscale Model 5, MM5）模拟了生长季气温和LUCC相互影响的过程。本文主要结论如下：（1）根据黑龙江省的种植面积统计资料，黑龙江省的农业开发时期基本分为农业扩张缓慢时期（1949-1980），农业结构调整时期（1980-2001）和农业扩张加速时期（2001-2008）。1976-2001年黑龙江省的粮食作物面积缓慢增加，其中水田面积增加，旱田面积减少；2001-2008年黑龙江省的粮食作物面积急剧增加，水田和旱田面积增速显著。（2）不同空间插值模型的交叉精度检验结果表明，基于DEM修正的协同克里金插值法精度最高，其次是考虑了站点海拔、经纬度的协同克里金法精度较高。四种插值模型的结果表明，黑龙江省生长季气温呈现西高东低，南高北低，平原高于山地的空间格局。基于DEM修正的协同克里金插值的生长季气温由于引入DEM高程数据而具有明显的地形分布特征；其它三种插值模型则表现出显著的地带分布特征，其中克里金法比反距离加权法更加明显。（3）EOF时空结构分离技术将33年生长季气温的时空结构分离为相互正交的气温分布模态。“一致型”生长季气温分布模态方差贡献率为57.77%，是黑龙江省生长季气温空间分布的常见类型，表现为整个区域33年间的生长季气温同步上升，平原地区的增温程度比山区大，东部比西部增温程度大，南部比北部增温程度大。（4）以黑龙江省农业开发最活跃、生长季气温变化最明显的挠力河流域子流域，作为研究LUCC对农业扩张和气候变化响应的典型农区。三江平原挠力河流域典型农区过去33年最显著的土地利用变化为湿地和林地被开发为农田，农田成为该地区最主要的土地利用类型，影响LUCC最主要的人类活动是农业扩张。土地利用综合指数模型表明，1976-2001年农区的土地利用程度增加显著，2001-2008年的土地利用程度增加不明显。（5）通过重心模型计算挠力河流域典型农区基于NDVI的土地利用的重心偏移，农业扩张下土地利用的重心偏移，运用矢量合成原理，得到气候变化导致的土地利用重心偏移。1976-2001年的土地利用重心由北偏西56度移动了15.56 km；土地利用程度在南北方向偏移强度上农业扩张的影响占94%，气候影响占6%；土地利用程度在东西方向偏移强度上气候影响占20%，农业扩张的影响占80%。2001-2008年的土地利用重心由南偏西44度移动了0.37 km；土地利用程度在南北方向偏移强度上，农业扩张的影响占30%，气候影响占70%；土地利用程度在东西方向偏移强度上气候影响占48%，农业扩张的影响占52%。（6）对挠力河流域典型农区1976-2008年生长季气温的线性拟合、Mann-kendall检验以及相对变率分析结果表明，33年来生长季气温一直呈上升趋势。1976-2001年生长季气温的上升趋势不稳定，气温变化程度较大；2001-2008年生长季气温上升趋势显著，且上升趋势一直增加，气温变化比上一时期更稳定。（7）结合2001年和2008年中分辨率成像光谱（Moderate-resolution Imaging Spectroradiometer，简称MODIS）来源的植被覆盖类型、归一化植被指数（Normalized Difference Vegetation Index，简称NDVI）和基于MM5的气温空间分布，分析了挠力河流域典型农区农业扩张下LUCC与生长季气温的关系。2001年和2008年各植被覆盖类型的生长季各月气温差异显著；各种植被覆盖类型转变为谷类作物和阔叶作物，气温均有所上升，其中“落叶阔叶林转变为谷类作物”和“落叶阔叶林转变为阔叶作物”气温上升幅度最大。说明农田扩张影响了农区气温，林地开垦为农田以及“旱改水”导致气温上升。NDVI与同期气温的相关性分析表明，植被NDVI与气温呈极显著正相关关系（α＜0.1）。2001-2008年其它植被覆盖地区改为种植谷类作物或阔叶作物，该区域植被NDVI对气温响应的敏感性升高。无论是气候变化还是农业扩张的作用，均导致生长季内作物对气温响应的敏感性升高，其中谷类作物比阔叶作物更敏感。

Heilongjiang province is one of the typical regions undergoing intensive human activities worldwide in the past few decades, where particularly the development of agriculture led to significant land use/land cover changes (LUCC). The agricultural expansions had significant impact on the regional climatic factors, and the interactions between climate system and land cover, resulting in changing the distribution pattern of regional temperature. The distribution pattern and long-term processs changes of temperature affected vegetation growth, thus leading to land cover changes. Reasrch about the relationship between LUCC and climate changes under agricultural expansions serves for agricultural development planning.The paper takes Heilongjiang province as the basic study area and analyses the characteristics of agricultural expansions over past few decades in Heilongjiang province. Using the geostatistical module of GIS the spatial distribution of temperature during the growing season (May to September) was simulated, and spatio-temporal variation structure of temperature during the growing season from 1976 to 2008 was extracted by the empirical orthogonal function (EOF). On the summary of the research above, a typical agricultural area in the Naoli basin of Sanjiang Plain was selected to analyse the response of LUCC to agricultural expansions and climate changes employing weight center model and simulate interactive process of temperature and LUCC by applying MM5. The conclusions of the research are as follows: (1)According to the statistics of crop area in Heilongjiang province, agricultural development stage is divided into slow agricultural expansions period (1949-1980), the agricultural restructuring period (1980-2001) and the period of accelerating agricultural expansions (2001-2008). The crop area of Heilongjiang Province was increasing from 1976 to 2001, while area of paddy fields increased and dry land area decreased. From 2001 to 2008 crops area increased dramatically, while paddy and dry land area increased significantly.(2) Cross-validation was applied to evaluate different spatial interpolation model. Accuracy of cokriging based on DEM was superior to the other three methods, followed by cokriging considering elevation, latitude and longitude of meteorological station.The four interpolation model results show that temperature during growing season in Heilongjiang province is high in the west and lower in east,and moreover high in the south and lower in the north. Besides, temperature in the plain is higher than in the mountain.(3) Spatio-temporal variation structure of temperature during the growing season over 33 years was separated into orthogonal temperature distribution modes by the use of EOF. The temperature distribution mode of “consistency”, with variance proportion accounting for 57.77%, is the dominant distribution mode. The “consistency” indicates the temperature in the whole study area has been rising over past 33 years.(4)The typical agricultural area in Naoli River Basin was selected to study the response of LUCC to agricultural expansions and climate changes. The most significant land use change over past 33 years was that wetlands and woodlands was developed into farmland and farmland became the main land use type in the agricultural area.The most important human activities affecting LUCC were agricultural expansions. Land use degree in the agricultural area had increased significantly from 1976 to 2001, whereas increased slightly from 2001 to 2008. (5) By weight center model NDVI and land use data were used to analyze the impact degree and direction of changes caused by climate changes and agricultural expansions in agricultural area.The dual impacts resulted in a shift of land use degree weight center northwestward by 15.56 km from 1976 to 2001 and southwestward 0.37 km from 2001 to 2008.With regard to land use degree excursion intensity from 1976 to 2001, in north-south direction 94% of that was caused by climatic changes and 6% of that by agricultural expansions,while in east-west direction 20% of that was caused by climatic changes and 80% of that by agricultural expansions. From 2001 to 2008, in north-south direction 70% of that was caused by climatic changes and 30% of that by agricultural expansions, while in east-west direction 48% of that was caused by climatic changes and 52% of that by agricultural expansions. (6)The linear fit, Mann-kendall test and relative variability analysis of temperature during growing season from 1976 to 2008 showed that temperature was rising over the past 33 years in the agricultural area of the Naoli River Basin. The upward trend of temperature is not stable from 1976 to 2001 while more stable from 2001 to 2008. (7)Using vegetation cover and NDVI data derived from moderate-resolution imaging spectroradiometer (MODIS) and spatial distribution of temperature based on MM5 in 2001 and 2008, interactive process of temperature and LUCC under agricultural expansions was analyzed.Converting other types of vegetation cover to cereal crop and broadleaf crop resulted in temperature declining. The conversions of deciduous broadleaf trees to these two crops caused more intensive decline in temperature. Reclaiming forest land for farmland and shifting dry farm to paddy field both led to the temperature rising. The study demonstrated that spatial distribution of temperature in the agricultural area was influenced by farmland expansion. (8) Correlation analysis of NDVI and temperature showed that NDVI had significant positive correlation with temperature(α<0.1). Converting other types of vegetation cover to cereal crop and broadleaf crop led to sensitivity of NDVI to temperature changes increasing.Under the influence of climate changes or agricultural expansions, the sensitivity of crop NDVI to temperature changes increased during the growing season, and cereal crop are more sensitive than broadleaf crop.