摘要
目前城市植被降温效率的研究大多基于大尺度卫星遥感数据来开展,缺少微尺度下植被降温效率的精细研究。因此,本研究以南京市江宁区典型居民区植被为研究对象,利用无人机可见光数据进行居民区绿地精细分类,在此基础上建立区域绿地容积率RGPR (Regional Green Plot Ratio)指标,基于逐小时无人机热红外数据,提出一种改进的植被降温效率计算方法—区域植被降温效率RCE (Regional Cooling Efficiency)计算方法,并利用该方法计算居民区植被降温效率,探究不同局地气候分区(LCZ)下居民区地表温度与区域绿地容积率指标的响应关系、降温效率时空变化并进一步确定不同居民区绿地容积率的最佳降温效率阈值。结果表明:(1)居民区植被降温效率日变化曲线整体呈现“山峰”形态,RCE随地表温度增强而增大。在观测时间段内,RCE最小值出现在8:00 (均<1.0℃),最大值出现在午后14:00 (均>1.4℃),局地气候分区水平下,紧凑型居民区的RCE高于开阔型居民区,而在开阔型居民区类型中,RCE随着区域内建筑平均高度的增加而降低。(2)紧凑型的局地气候分区下,RGPR越高,植被所带来降温效果越强;而开阔型居民区,无论建筑高低,植被降温效率存在一定的RGPR阈值,当RGPR达到一定阈值后,RGPR对地表温度的降温效率达到最大强度。本研究可为城市居民区绿地规划、改善城市微热环境提供科学依据。
Most previous studies on the cooling efficiency of urban vegetation are based on large-scale satellite remote sensing data, which leaves a gap in fine-scale investigations at the micro-level. Therefore, this study took the vegetation of typical residential areas in Jiangning District of Nanjing City as the research object. Visible light data from Unmanned Aerial Vehicles(UAVs) were used to obtain the fine classification of residential green space, and the Regional Green Plot Ratio(RGPR) index was constructed.We proposed an improved calculating method of vegetation cooling efficiency, that is, Regional Cooling Efficiency(RCE). RCE is based on hour-by-hour UAV thermal infrared data. We applied this method to calculate the cooling efficiency of vegetation in residential areas. This way enabled us to investigate the response relationship between the surface temperature of different local climate zones in residential areas and the RGPR indicator. The optimal thresholds of cooling efficiency for different RGPRs in residential areas could also be determined.Results showed that(1) the daily variation curve of the cooling efficiency of vegetation in the residential area exhibited a “peak”pattern, and the RCE increased with the improvement in solar radiation. During the observation period, the minimum value of RCE appeared at 8:00 a.m.(all lower than 1.0 ℃), and the maximum value appeared at 14:00 p.m.(all higher than 1.4 ℃). At the level of local climate zone, the RCE of compact residential areas was higher than that of open residential areas. In the case of open residential areas, the RCE decreased with the increase in the average height of the buildings in the area.(2) Under compact local climate zone, the higher RGPR meant a stronger cooling effect brought by vegetation. Meanwhile, in open residential areas, regardless of the height of the building, a certain RGPR threshold was observed for the cooling efficiency of vegetation. When the RGPR reached a certain threshold, the cooling efficiency of the RGPR on sur
作者
孙嘉欣
冯莉
张枭
周亚男
冯海蓉
SUN Jiaxin;FENG Li;ZHANG Xiao;ZHOU Yanan;FENG Hairong(College of Geography and Remote Sensing,Hohai University,Nanjing 211100,China)
出处
《遥感学报》
EI
CSCD
北大核心
2024年第8期1899-1913,共15页
NATIONAL REMOTE SENSING BULLETIN
基金
国家自然科学基金(编号:42077431)。
关键词
城市居民区
微热环境
区域植被降温效率(RCE)
局地气候分区
区域绿地容积率
无人机热红外
降温效率阈值
城市居民区绿地规划
urban residential areas
microthermal environment
Regional Cooling Efficiency(RCE)
local climate zone
regional green plot ratio(RGPR)
UAV thermal infrared remote sensing
cooling efficiency threshold
green space planning in urban residential areas
