基于无人机遥感的蒸散发测算--以龙华区重点发展片区为例

Evapotranspiration measurement based on UAV remote sensing:A case study of main development areas in Longhua District

蒸散发是研究一个地区水量平衡、能量平衡、植被生理健康评价和水资源管理估算的重要参数。本研究基于三温模型,结合无人机遥感、Landsat 8、地面观测,获得了龙华区九龙山数字城、鹭湖中心城这2个重点发展片区的蒸散发年均值,并对结果进行分析,主要结论如下:1)从空间分布来看,龙华区重点发展片区蒸散发年均值空间异质性高,数值区间在0~1233 mm/a。2)九龙山数字城的年均蒸散发值要显著高于鹭湖中心城。九龙山数字城核心区年均蒸散发平均值约678 mm,鹭湖中心城核心区约443 mm。3)九龙山数字城的蒸散发年均值空间分布差异大于整个研究区域的平均值。九龙山数字城核心区的中部区域年均蒸散发平均值约984 mm,远高于研究区其他区域;九龙山数字城核心区和协调区交接处的年均蒸散发平均值约422 mm,与鹭湖中心城核心区年均蒸散发平均值接近。4)人类活动影响和植被大面积枯萎是造成鹭湖中心城核心区蒸散发值相对较低的主因。5)整个研究区域的年均蒸散发总量为5.52×10^(6)m^(3)。其中,林地的年均蒸散发总量最多,为3.27×106 m^(3),占研究区域总量的59.24%;园地、裸地、水域和草地年均蒸散发总量大致相同,在3.29×10^(5)~5.48×10^(5)m^(3);人工下垫面面积占研究区域的56.18%,年均蒸散发总量却只占研究区域的8.82%。6)研究区域的蒸散发总量的主要贡献植被类型是乔木绿地。7)本研究可为特定区域的生态系统服务功能评估和精细化生态资源管理提供基础数据支持。

Evapotranspiration(ET)is an important parameter to study water balance,energy balance,vegetation physiological health evaluation and water resources management estimation.Based on the three-temperature model,combined with UAV remote sensing,Landsat 8 and ground observation,the annual average evapotranspiration of Jiulongshan Digital City and Luhu Central City in Longhua District was obtained,and the results were analyzed.The main conclusions are as follows:(1)From the perspective of spatial distribution,the annual average evapotranspiration of main development areas in Longhua District has high spatial heterogeneity,and the value range is 0~1233 mm/year.(2)The annual average evapotranspiration of Jiulongshan Digital City is significantly higher than that of Luhu Central City.The annual average evapotranspiration in the core area of Jiulongshan Digital City is about 678 mm,and that in the core area of Luhu Central City is about 443 mm.(3)The spatial distribution difference of the annual average evapotranspiration in Jiulongshan Digital City is greater than the average value of the whole study area.The annual average evapotranspiration in the central area of the core area of Jiulongshan Digital City is about 984 mm,which is much higher than other areas of the study area.The annual average evapotranspiration at the junction of the core area and coordination area of Jiulongshan Digital City is about 422 mm,which is close to the annual average evapotranspiration in the core area of Luhu Central City.(4)Human activities and large-scale vegetation withering are the main reasons for the relatively low evapotranspiration in the core area of Luhu Central City.(5)The annual total evapotranspiration of the whole study area is 5.52×10^(6)m^(3).The annual total evapotranspiration of forest land is the highest,which is 3.27×10^(6)m^(3),accounting for 59.24%of the total amount of the study area.The annual total evapotranspiration of garden land,bare land,water area and grassland is roughly the same,ranging from 3.29×10^(5)to 5.48×10^(5)m^(3).The area of artificial underlying surface accounts for 56.18%of the study area,but the annual total evapotranspiration only accounts for 8.82%of the study area.(6)The main vegetation type contributing to the total evapotranspiration in the study area is arbor green space.(7)This study can provide basic data support for ecosystem service evaluation and refined ecological resource management in specific areas.