地理科学进展 ›› 2014, Vol. 33 ›› Issue (6): 815-824.doi: 10.11820/dlkxjz.2014.06.010

• 气候与环境变化 • 上一篇    下一篇

土地利用类型转换对地表能量平衡和气候的影响——基于SiB2模型的模拟结果

刘凤山1,2, 陶福禄1, 肖登攀3, 张帅1,2, 王猛1,2, 张贺1,2   

  1. 1. 中国科学院地理科学与资源研究所, 北京 100101;
    2. 中国科学院大学, 北京 100049;
    3. 河北省科学院地理科学研究所, 石家庄 050011
  • 收稿日期:2013-12-01 修回日期:2013-12-01 出版日期:2014-06-25 发布日期:2014-06-25
  • 通讯作者: 陶福禄,男,博士,研究员,主要从事生态系统生态学、全球变化生态学方面研究,E-mail:taofl@igsnrr.ac.cn。 E-mail:taofl@igsnrr.ac.cn
  • 作者简介:刘凤山(1986- ),男,山东潍坊人,博士研究生,主要研究方向为土地利用变化对气候的生态效应和机理,E-mail:liufengshan0225@163.com。
  • 基金资助:
    国家重点基础研究发展计划(973 计划)项目(2010CB950900)。

Influence of land use change on surface energy balance and climate:results from SiB2 model simulation

LIU Fengshan1,2, TAO Fulu1, XIAO Dengpan3, ZHANG Shuai1,2, WANG Meng1,2, ZHANG He1,2   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China;
    3. Institute of Geographical Sciences, Hebei Academy of Sciences, Shijiazhuang 050011, China
  • Received:2013-12-01 Revised:2013-12-01 Online:2014-06-25 Published:2014-06-25

摘要: 利用SiB2 模型对中国东北地区农田、草地和森林3 种土地利用类型的地表能量平衡过程展开研究,分析不同土地利用类型对生物地球物理参数(反照率和粗糙度)、能量平衡(净辐射、潜热和显热)和气候(冠层温度)的影响。结果表明:①模型模拟的地表能量平衡与实测数据的年变化动态相似(R2>0.42),差值保持在±30 W/m2,温度在±4 ℃。②利用相同气象数据模拟不同土地利用类型通过生物地球物理过程对地表能量平衡和气候的影响,发现森林吸收的净辐射最高且主要用于潜热分配,农田的净辐射最低且主要用于显热分配,草地净辐射和能量分配居中。③生态系统获得的净辐射主要受反照率的影响,净辐射分配受叶面积指数的调节。④冠层温度(℃)受反照率和净辐射在潜热和显热间分配的相对重要性的影响:年平均值为森林(7.7)>农田(7.64)>草地(6.67)。⑤降水对模拟结果有显著影响,是森林模拟差异的主要原因。在不同土地利用类型中,降水增加土壤水分,净辐射更多分配到潜热,较少分配到显热,降低冠层温度。

关键词: SiB2 模型, 地表能量平衡, 反照率, 土地利用和覆被变化, 叶面积指数

Abstract: The influence of land use and cover change (LUCC), by means of biogeophysical processes, on surface energy balance and climate is highly concerned by climate scientists. Driven by spatially interpolated meteorological data and remote-sensing derived leaf area index validated by on-site observations, the Simple Biosphere model (SiB2) was used to simulate the surface energy balances for different land use types, i.e. farmland, grassland and forest in northeast China, from 2001 to 2010. The SiB2 model validation was done by comparing simulation results with observed surface energy balance components and temperature in 2003 for the three land use types. The effects of LUCC on surface energy balance and climate was based on the average simulation outcomes in 2001-2010. Biogeophysical parameters (including albedo and roughness length), surface energy balances (net radiation flux, latent heat flux and sensible heat flux) and climate (canopy temperature) were analyzed to demonstrate the influences of LUCC. The results show that: (1) The simulated and observed data have similar annual trends (R2>0.42) but there is a gap of ±30 W/m2 for energy balance components and ±4 ℃ for temperature, based on annual averages. The model imitated the surface energy balance and temperature very well, and was used in the simulation of surface energy balance in northeast China. Sensitivity analysis revealed that the major influencing factor of surface energy partitioning was leaf area index, not vegetation cover as set in the SiB2 model. (2) The impacts of different land use types on surface energy balance and climate through biogeophysical processes were simulated using the same meteorological data for the purpose of eliminating the effects of meteorological conditions. The 10 year averages showed that albedo was lowest in forest, followed by grassland and farmland, while forest > farmland > grassland for leaf area index, forest < grassland < farmland for Bowen Ratio and forest > farmland > grassland for roughness length. (3) Trapped net radiation by ecosystem was primarily determined by albedo. Forest traps the highest net radiation, which is mainly allocated into latent heat flux; farmland traps the lowest net radiation, which is mostly channeled into sensible heat flux, and grassland is in between for both net radiation and its partitioning. (4) Canopy temperature (℃) was determined by the relative importance of albedo and the partitioning of net radiation into latent and sensible heat fluxes: forest (7.7)>farmland (7.64) > grassland (6.67), on annual average. The highest temperature of forest was decided by the lowest albedo, but the higher temperature of farmland as compared to grassland was caused by the higher Bowen ratio of farmland. (5) Precipitation was the predominant impact variable on surface energy balances, and was the main cause of the deviation of SiB2 simulation for forest. With the increment of precipitation in all three land use types, the net radiation flux partitioning into latent heat flux was enhanced, and that into sensible heat flux was weakened, as rain increases soil water content; at the same time, canopy temperature also decreased. The results of this research support the warming effect of farmlands converted from grasslands, which have taken place in northeast China over the past few decades.

Key words: albedo, leaf area index, LUCC, SiB2 Model, surface energy balance

中图分类号: 

  • P404