摘要
利用2013—2019年5—9月MOD13Q1植被监测产品及同期区域气象站观测资料,应用最大值合成法、趋势线分析模型、相关性分析法,研究了归一化植被指数(NDVI)和气象要素的变化特征、植被时空变化率及NDVI对气候的响应。结果显示:(1)秦岭山区西安段NDVI由东北向西南依次递增,气温与NDVI趋势基本相反,降水和相对湿度与NDVI趋势基本一致。(2)逐年最大NDVI、平均气温、降水总量和平均相对湿度均呈上升趋势;5—7月NDVI、平均气温逐渐增高,8—9月逐渐降低;5—9月逐月降水量和相对湿度逐渐增加。(3)坡脚面区域因城市化发展而出现植被退化现象,秦岭高山区域植被改善显著;各区县改善面积占比自西向东依次减少;西部3个区县改善区域大于退化区域。(4)7月上半月及以前气温与NDVI呈负相关,7月下半月及以后与NDVI呈正相关;降水与NDVI呈正相关,且从8月开始NDVI对降水响应出现滞后性;7月下半月及以后相对湿度与同期NDVI呈正相关。研究表明秦岭山区西安段植被覆盖呈上升趋势,西部地区植被改善明显,且山区植被对降水的响应较为明显。
Using the MOD13Q1 vegetation monitoring products from May to September in 2013-2019 and the observation data of regional meteorological stations in the same period,based on the maximum value composite,trend line analysis model and correlation analysis method,this paper researched the change characteristics of NDVI and meteorological elements,the spatiotemporal change rate of vegetation and the response of NDVI to climate.The results show that:(1)NDVI increases from northeast to southwest in Xi′an section of Qinling mountains,and the trend of temperature and NDVI is opposite,while precipitation and relative humidity are consistent with NDVI trend.(2)The maximum NDVI,average temperature,total precipitation and average relative humidity increased year by year;NDVI and average temperature increased from May to July,decreased from August to September,and monthly precipitation and relative humidity increased from May to September.(3)The vegetation degradation occurs in the slope toe area due to urbanization,and the vegetation of Qinling alpine area has been improved significantly;the proportion of improvement area of each district and county decreased from west to east;the improvement area of the three districts and counties in the west was greater than the degradation area.(4)The temperature was negatively correlated with NDVI before the first half of July,and positive correlation after the second half of July;precipitation was positively correlated with NDVI,and the response of NDVI to precipitation began to lag in August;there was a positive correlation between relative humidity and NDVI after the second half of July.The vegetation coverage in Xi′an section of Qinling mountains shows an upward trend,the vegetation in the western area has improved significantly,and the response of vegetation in the mountain area to precipitation is more obvious.
作者
金丽娜
李雄飞
曲静
杨晓春
JIN Lina;LI Xiongfei;QU Jing;YANG Xiaochun(Xi'an Meteorological Bureau of Shaanxi Province,Xi'an 710016,China;Shaanxi Monitoring Center of Soil and Water Conservation & Eco-environment,Xi'an 710004,China)
出处
《甘肃科学学报》
2022年第3期65-72,共8页
Journal of Gansu Sciences
基金
2020年西安市科技局项目“科技+‘行动计划-(18)农业技术研发项目’基于遥感技术的智慧农业气象服务系统”(20NYYF0049)。
关键词
秦岭西安段
植被
气候
时空特征
Xi′an section of Qinling mountains
Vegetation
Climate
Temporal and spatial characteristics
