Vertical distribution of NDVI in typical karst regions of Guizhou and Guangxi
-
摘要: 黔桂喀斯特山地地形复杂,植被覆盖度垂直特征分异显著,以往研究多从气候因子响应方面探讨其垂直分布差异,而研究区人地矛盾尖锐,人类活动对植被分布有重要的影响。文章以黔桂喀斯特山地为例,利用2010年MODIS13Q1 NDVI数据表征植被覆盖度,结合高程、坡度和坡向等地形特征,不同土地利用类型的分布情况,叠置分析研究区的NDVI垂直分布特征。结果表明:黔桂喀斯特山地以林地、耕地和草地为主,不同土地利用类型随海拔、坡度和坡向的变化呈现不同的分布特征。研究区NDVI平均值为0.59,其中林地NDVI最大,达到0.63,草地为0.58,耕地最小为0.54。空间分布上,贵州境内NDVI值大部分为0.5~0.6,广西境内自西北向东南NDVI值由0.8逐渐降低至0.4,以0.6~0.7为主。NDVI在垂直梯度上分布特征显著,与植被垂直地带性分布以及不同地类的垂直分布特征有密切关系。海拔分布上,NDVI在海拔小于200 m区间最小,400~600 m的区间最大;北部贵州整体海拔较高,但植被覆盖度较低;南部广西海拔较低,但植被覆盖度较高。坡度分布上,在坡度小于35°范围,随坡度增大,耕地、水域、建设用地面积迅速减少,林草地面积逐步增加,使得NDVI随坡度增大逐渐增大。坡向分布上,NDVI不随坡向变化呈现明显变化,仅偏东坡向稍大于偏西坡向。研究表明应根据海拔和坡度等地形特征,并考虑土地利用情况,因地制宜进行生态建设。Abstract: Karst regions in Guizhou and Guangxi are characterized by complex topography and highly variable vegetation coverage. Previous studies commonly focused on the vertical distribution of NDVI from the perspective of the response of climatic factors. Because of the sharp contradiction between human and land, human activities have an important impact on vegetation distribution. This paper uses MODIS13Q1 NDVI data of the year 2010 to characterize vegetation coverage in the karst regions. Based on previous analysis, this paper takes elevation, slope, slope aspect as well as different land uses into account to calculate the NDVI vertical distribution characteristics. Results show that the main land use types in the karst regions include forests, arable land and grassland, and different land use types show different distribution characteristics along with the differences in elevation, slope and slope aspect. The mean value of NDVI is 0.59, among which the NDVIs of forests, grassland and arable land are 0.63, 0.58 and 0.54, respectively. In spatial distribution, the majority of NDVI values in Guizhou vary from 0.5 to 0.6, while those in Guangxi drop from 0.8 to 0.4 from the northwest to the southeast dominated by the range of 0.6-0.7. The distribution feature of NDVI on the vertical gradient is notable, closely related to the vertical zoning of vegetation and the vertical distribution characteristics of different land use types. Altitudinally, NDVI value is the smallest at an altitude of less than 200m, but reaches its largest at 400-600m; at the same time the altitude of Guizhou is higher but the vegetation coverage is lower, and Guangxi has a lower altitude but higher vegetation coverage. In respect of slope gradient, where the slope is less than 35 degree, the arable land, water area and construction land decrease rapidly, but the areas of forests and grassland increase gradually and the NDVI increases accordingly. As for the slope aspect, NDVI is basically the same on slopes with different facing directions, with values on the eastward slopes slightly greater than the westward slopes. These features show that the ecological construction should be carried out according to the terrain characteristics such as elevation and slope as well as the land use types.
-
Key words:
- NDVI /
- vertical distribution /
- land use /
- typical karst region
-
[1] 马志勇, 沈涛, 张军海, 等. 基于植被覆盖度的植被变化分析[J]. 测绘通报, 2007(3):45-48. [2] Yu Z Z, Zhu J G, Qian Y L. Analysis on terrain effects to vegetation coverage by quantitative remote sensing[J]. Advanced Materials Research, 2012, 518-523:5673-5677. [3] 杨汉奎主编. 喀斯特环境质量变异[M]. 贵阳: 贵州科技出版社, 1994, 32-33. [4] 童晓伟, 王克林, 岳跃民, 等. 桂西北喀斯特区域植被变化趋势及其对气候和地形的响应[J]. 生态学报, 2014, 34(12):3425-3434. [5] 李晓印. 基于 GIS 的植被空间格局研究:以在陕西省耀县的实验为例[D]. 西安: 西北大学, 2004:24-30. [6] Rouse J W, Haas R H, Schell J A, et al. Monitoring vegetation systems in the Great Plains with Erts[C]. Proceedings of Third ERTS Symposium.Washington DC: NASA, 1973:309-317. [7] Zhan Z Z, Liu H B, Li H M, et al. The relationship between NDVI and terrain factors-A Case study of Chongqing[J]. Procedia Environmental Sciences, 2012, 12(Part B):765-771. [8] 邓煜霖, 塔西甫拉提?特依拜, 姜红涛, 等. 艾比湖流域 NDVI 垂直梯度变化特征[J]. 中国沙漠, 2015, 35(2):508-513. [9] 朱烨, 方秀琴. 青藏高原植被覆盖度与地形相关性分析[J]. 地理空间信息, 2015, 13(6):135-137+15. [10] 申彦科. 重庆缙云山植被覆盖度变化及空间格局研究[D]. 北京: 北京林业大学, 2010:34-38. [11] 金晓媚, 万力, 胡光成. 黑河上游山区植被的空间分布特征及其影响因素[J]. 干旱区资源与环境, 2008, 22(6):140-144. [12] Walsh S J, Crawford T W, Welsh W F, et al. A multi-scale analysis of LULC and NDVI variation in Nang Rong district, northeast Thailand[J]. Agriculture Ecosystems & Environment, 2001, 85(1):47-64. [13] 金远亮, 王忠, 张林. 西藏当雄县高寒草地 NDVI 的海拔分异特征及其指示[J]. 自然资源学报, 2015, 30(6):929-937. [14] 喻素芳, 佘光辉, 罗叶红, 等. 基于 MODIS-NDVI 数据广西植被覆盖变化特征分析[J]. 湖北农业科学, 2015, 54(2):321-325. [15] 廖克, 国家地图集编纂委员会, 中国科学院地理研究所.中华人民共和国国家自然地图集[CM].北京:中国地图出版社,1999. [16] 吕拉昌主编. 中国地理[M]. 北京: 科学出版社, 2013:480. [17] 宋同清主编. 西南喀斯特植物与环境[M]. 北京: 科学出版社, 2015:59-80. [18] Tucker C J, Pinzon J E, Brown M E, et al. An extended AVHRR 8–km NDVI dataset compatible with MODIS and SPOT vegetation NDVI data[J]. International Joural of Remote Sensing, 2005, 26(20):4485-4498. [19] Holben B N. Characteristics of maximum-value composite images for temporal AVHRR data[J]. International Journal of Remote Sensing, 1986, 7(11):1417-1434. [20] 章皖秋, 李先华, 罗庆州, 等. 基于RS、GIS的天目山自然保护区植被空间分布规律研究[J]. 生态学杂志, 2003, 22(6):21-27. [21] 贺敬滢, 张桐艳, 李光录,等. 基于DEM的土地利用与地形因子关系研究:以商州区张地沟小流域为例[J]. 干旱地区农业研究, 2012, 30(2):206-212. [22] 朱林富, 杨华. 基于MODIS数据的重庆NDVI时空分异研究[J].重庆师范大学学报(自然科学版), 2015,32(2):38-43+2.
点击查看大图
计量
- 文章访问数: 1859
- HTML浏览量: 558
- PDF下载量: 637
- 被引次数: 0