基于遥感的安顺夜郎湖植被干旱响应特征

doi:10.3969/j.issn.1004-9479.2021.05.2019640

摘要/Abstract

摘要：

根据多年的气象资料和K干旱指数，分析了夜郎湖区域气候变化特征及其干旱背景，运用干旱年份（2009年11月—2010年3月）的4景Landsat卫星遥感数据计算了区域的归一化植被指数（NDVI）和修正的归一化水体指数（MNDWI），重点分析了夜郎湖植被对干旱事件的响应特征，并探讨了极端干旱事件对湖泊生态系统的影响。结果表明：（1）夜郎湖水库及其周边地区表现出变冷变干的气候特征，1995—2012年间气温呈显著变冷的趋势（R²=0.54，P<0.05），而年降水量表现出波动下降的趋势（R²=0.42，P<0.05）。2009年是夜郎湖自1995年以来降水相对稀少，同时也是干旱最为严重的年份（K<0.6）。（2）当水库的K干旱指数小于0.4（特旱）时，NDVI和植被面积呈显著下降的趋势即表现出大范围的缺水性死亡，干旱开始时水库对周边植被具有一定的调节作用，基本维持原有水平，之后水库调节能力下降，植被生长受到极度抑制，出现大范围的死亡。而水库水面因受到蒸发量增大与降水量减少的影响，水分逐渐丧失，面积呈逐渐递减的特征。（3）湖泊生态系统在面对特大干旱时植被的应对能力相对较差，地表水极其缺乏，植物根系无法获得维持其生存的水分，随着干旱程度的加深而大面积死亡。

关键词: 遥感, K干旱指数, NDVI, MNDWI, 夜郎湖水库, 植被

Abstract:

Based on the meteorological data and k-drought index data for many years, this paper analyzes the characteristics of climate change and its drought background in Yelang Lake region, calculates the NDVI and MNDWI of the region by using the remote sensing data of four Landsat satellites in drought years (November 2009 -March 2010), and focuses on the impact of Yelang lake vegetation on drought events The effects of extreme drought on lake ecosystem are discussed. The results show that: (1) Yelang lake water reservoir and its surrounding areas show the climate characteristics of becoming cold and dry. The temperature shows a significant trend of becoming cold from 1995 to 2012 (R² = 0.54, P < 0.05), while the annual precipitation shows a trend of fluctuation and decline (R²= 0.42, P < 0.05). In 2009, the precipitation of Yelang lake is relatively rare since 1995, and it is also a severe drought year (K< 0.6). (2) When the k-drought index of the reservoir is less than 0.4 (extreme drought), NDVI and vegetation area show the characteristics of significant decline, that is, large-scale water shortage death. At the beginning of the drought, the reservoir has a certain regulating effect on the surrounding vegetation, basically maintaining the original level, and then the regulating capacity of the reservoir decreases, and the vegetation growth is extremely inhibited, resulting in large-scale death. However, due to the increase of evaporation and the decrease of precipitation, the water content of the reservoir surface is gradually lost and the area is gradually decreasing. (3) In the face of severe drought, the response ability of vegetation in lake ecosystem is relatively poor, the surface water is extremely scarce, the plant root system can not obtain the water to maintain its survival, and with the deepening of drought, a large area of death occurs. At the same time, the living space and resources of aquatic animals and plants in the reservoir are relatively reduced, the lake ecosystem is degraded and the ecosystem service value is reduced.

Key words: remote sensing, K drought index, NDVI, WNDWI, Yelanghu Reservoir, vegetation

娄昭, 李维杰, 王家录, 王勇, 任娟. 基于遥感的安顺夜郎湖植被干旱响应特征[J]. 世界地理研究, 2021, 30(5): 1015-1023.

Zhao LOU, Weijie LI, Jialu WANG, Yong WANG, Juan REN. Drought response characteristics of vegetation in the Yelanghu Reservoir of Anshun on remote sensing[J]. World Regional Studies, 2021, 30(5): 1015-1023.

图/表 9

图1 安顺夜郎湖水库研究区位图

Fig.1 The map of the research area of Yelanghu Reservoir in Anshun City

表1 2009年11月—2010年3月的4景Landsat遥感影像

Tab.1 Landsat remote sensing image of 4 scenes from November 2009 to March 2010

传感器类型	分别率	轨道号	日期
Landsat-ETM+	30m	128/42	2009/11/4
Landsat-ETM+	30m	128/42	2010/1/7
Landsat-ETM+	30m	128/42	2010/2/8
Landsat-ETM+	30m	128/42	2010/3/12

表2 K指数干旱等级划分表

Tab.2 K index drought classification table

等级	类型	春、夏季尺度	等级	类型	秋、冬季尺度
1	无旱	K>0.8	1	无旱	K>1.0
2	轻旱	0.6<K≤0.8	2	轻旱	0.8<K≤1.0
3	中旱	0.4<K≤0.6	3	中旱	0.6<K≤0.8
4	重旱	0.1<K≤0.4	4	重旱	0.4<K≤0.6
5	特旱	K≤0.1	5	特旱	K≤0.4

图2 1995—2012年研究区年均温与年降水量变化趋势

Fig.2 Trends in annual ave-temperature and annual precipitation in the study area from 1995 to 2012

图3 研究区K干旱指数变化趋势

Fig.3 Trend of K Drought Index in study area

图4 研究区月K干旱指数与气温、降水量的相关性

Fig.4 Correlation between monthly K drought index and temperature and precipitation in the study area

表3 影像对应时期的干旱特征与气象要素

Tab.3 Drought characteristics and meteorological elements in the corresponding period of image

影像时间	NDVI	植被面积/km²	水面面积/km²	k干旱指数	降水量/mm	蒸发量/mm	气温/℃
2009/11/4	0.41	147.43	26.95	0.13	6.3	69.1	9.94
2010/1/7	0.38	130.26	12.85	0.07	2.6	49.3	6.93
2010/2/8	0.20	46.04	10.60	0.06	2.2	80.6	8.95
2010/3/12	-0.06	0.98	8.16	0.04	1.7	112.2	12.32

图5 夜郎湖水库4个时期NDVI空间格局

Fig.5 NDVI spatial pattern of the four periods of Yelanghu Reservoir

图6 研究区月K干旱指数与对应期NDVI、水面面积相关性

Fig. 6 Correlation between monthly drought index and NDVI and water surface area in the study area

参考文献 23

1	IPCC.Managing the risks of extreme event and disasters to advance climate adaptation:special report of the intergovernmental panel on climate change. Cambridge: Cambridge University Press,2012:582.
2	夏阳,严小冬,龙园,等.GEV指数表征的贵州夏旱分布特征及干旱事件的异常环流特征. 云南大学学报:自然科学版, 2017,39(2):252-264.
	Xia Y, Yan X, Long Y, et al. On interannual distribution variations of summer drought in Guizhou and analysis of abnormal circulation on drought event. Journal of Yunnan University: Natural Sciences, 2017, 39(2):252-264.
3	杨维西.全球变化中的中国干旱区-响应与趋势.林业科学,2008,44(8):124-131.
	Yang W. China's arid regions in the global change: Response and trend. Forestry Science, 2008,44(8):124-131.
4	李月,白晓永,周运超,等.基于SPEI的贵州省近60年干旱时空特征分析.中国水土保持,2015(7):57-60.
	Li Y, Bai X, Zhou Y C, et al. Variations of drought based on SPEI in recent 60 years on Guizhou. Soil and Water Conservation in China, 2015(7) :57-60.
5	王劲松,李忆平,任余龙,等.多种干旱监测指标在黄河流域应用的比较.自然资源学报, 2013,28(8): 1337-1350.
	Wang J, Li Y, Ren Y, et al. Comparison among several drought indices in the Yellow River Valley. 2013, 28(8): 1337-1350.
6	马柱国,符淙斌.1951-2004年中国北方干旱化的基本事实.科学通报,2006,51(20):2429-2439.
	Ma Z, Fu C. The basic fact of drying tendency in North China from 1951 to 2004. Chinese Science Bulletin, 2006, 51 (20) :2429-2439.
7	刘海文,丁一汇.华北夏季降水的年代际变化.应用生态学报,2011,22(2):129-137.
	Liu H, Ding Y. The interdecadal variability of summer precipitation over North China. Journal of Applied Meteorological Science, 2011,22 (2) :129-137.
8	王素萍,段海霞,冯建英.2009 /2010年冬季全国干旱状况及其影响与成因.干旱气象,2010,28(1):107-112.
	Wang S, Duan H, Feng J. The influence and cause of drought in China in winter (2009/2010) .Journal of Arid Meteorology, 2010, 28 (1) :107-112.
9	王素萍,段海霞,冯建英.2011年春季全国干旱状况及其影响与成因.干旱气象,2011,29(2):261-268.
	Wang S, Duan H, Feng J. The influence and cause of drought in China in spring in 2011. Journal of Arid Meteorology, 2011, 29 (2) :261-268.
10	姚玉璧,张强,王劲松.中国西南干旱对气候变暖的响应特征.生态环境学报,2014,23(9):1409-1417.
	Yao Y, Zhang Q, Wang J. The response of drought to climate warming in southwest in China. Ecology and Environmental Sciences, 2014,23(9):1409-1417.
11	黄荣辉,刘永,王林,等. 2009年秋至2010年春我国西南地区严重干旱的成因分析.大气科学, 2012,36(3): 443-457.
	Huang R, Liu Y, Wang L, et al. Analyses of the causes of severe drought occurring in southwest China from the fall of 2009 to the spring of 2010.Chinese Journal Atmosphere Science, 2012, 36 (3) :443-457.
12	慎东方,樊华.基于SPEI的贵州近60年干旱时空规律分布.中国水运,2014,14(11):201-204.
	Shen D, Fam H. Spatial and temporal distribution of drought based on SPEI in the past 60 years in Guizhou province. China Water Transport, 2014,14(11):201-204.
13	王劲松,郭江勇,周跃武,等.干旱指标研究的进展与展望.干旱区地理,2007,30(1):60-65.
	Wang J, Guo J, Zhou Y, et al. Progress and prospect on drought indices research.Arid Land Geography, 2007,30 (1) :60-65.
14	吴哲红,詹沛刚,陈贞宏,等.基于CL指数和K指数的近40a贵州安顺区域干旱演变特征.冰川冻土, 2013, 35(4): 1044-1055.
	Wu Z, Zhan P, Chen Z. The nearly 40-year drought evolution characteristics of Anshun municipality assessed by CI and K drought indexes. Journal of Glaciology and Geocryology, 2011,33 (5) :1040-1045.
15	黄会平.1949-2007年我国干旱灾害特征及成因分析.冰川冻土,2010,32(4):659-665.
	Huang H. Analysis of the characteristics and causes of drought in China from 1949 to 2007. Journal of Glaciology and Geocryology, 2010, 32 (4) :659-665.
16	王劲松,郭江勇,倾继祖.一种K干旱指数在西北地区春旱分析中的应用.自然资源学报, 2007,22(5): 709-718.
17	Wang J, Guo J, Qing J. Application of a kind of K drought index in the spring drought anal-ysis in Northwest China.Journal of Natural Resources, 2007, 22 (5) :709-717.
18	陈莉,蔡雄飞,王济,等.西南特大干旱条件下贵州西部山地土壤含水量变化研究.中国水土保持, 2014(11):60-64.
	Chen L, Cai X, Wang J, et al. Soil moisture changes of the mountainous area in west of Guizhou under the conditions of severe drought of Southwest China. Soil and Water Conservation in China, 2014(11):60-64.
19	卫捷,陶诗言,张庆云.Palmer干旱指数在华北干旱分析中的应用.地理学报,2003,58(增):91-99.
	Wei J, Tao Shiyan, Zhang Qingyun. Analysis of drought in North China based on the Palmer severity drought index. Acta Geographica Sinica, 2003,58 (S1) :91-99.
20	Mishra A K,Singh V P. A review of drought concepts. Journal of Hydrology, 2010,391(1-2):202-2016.
21	陈宜瑜,吕宪国.湿地功能与湿地科学的研究方向.湿地科学,2003,1(1):7-12.
	Chen Y, Lv X, The function and research tendency of wetland. Wetland Science, 2003, 1(1):7-12.
22	Tucker C J. Red and photographic infrared linear combinations for monitoring vegetation. Remote Sensing of Environment,1979,8(2):127-150.
23	徐涵秋.利用改进的归一化差异水体指数(MNDWI)提取水体信息的研究.遥感学报,2005,9(5):589-595.
	Xu H. A study on information extraction of water body with the modified normalized difference water index (MNDWI). Journal of Remote Sensing, 2005,9(5):589-595.