摘要
在多年连续干旱下,云南省森林植被遭受到了缺水和虫害的双重威胁。为明晰在干旱和虫害干扰下植被的状态及其变化,以墨江县为例,基于2006—2015年间MODIS的EVI产品数据、气象数据和虫害信息,开展了植被指数对气象数据和虫害信息的敏感性分析,并提出了一个新的低谷深度指数DEVI和一个考虑滞后性的EVI预测模型。研究表明:(1)EVI对降雨量的响应存在时间尺度效应和滞后性。在月尺度上,EVI与同期降雨量存在显著正相关(P<0.05);通过滞后性分析发现,植被对气候因子响应存在明显滞后效应,对温度和降雨量响应的滞后期分别为2个月和1个月,且植被对温度的滞后响应高于对降雨的滞后响应。考虑降雨量和温度的滞后模型可以有效预测下个月的EVI(r=0.84)。(2)虫害和干旱干扰会降低植被对气候的响应敏感性。(3)DEVI指数在虫害年份(0.045±0.014)显著高于非虫害年(-0.003±0.011)。
Under successive years of drought, forest in Yunnan Province suffer from the threats of water shortage and insect pests. In order to understand the status of vegetation and its changes under drought and pest disturbance, the sensitivity of EVI to meteorological data and pest information was studied in Mojiang County, based on MODIS EVI product data, meteorological data and pest information during the period of 2006-2015. A new index of DEVI and an EVI forecasting model with consideration of lag effect were proposed. The result showed that：（1） On the monthly scale, there was a significant positive correlation between EVI and precipitation（P 0.05）, and the response of vegetation to climate factors had obvious lag effect. The lag periods of vegetation response to temperature and precipitation were 2 months and 1 month, respectively, and the response of vegetation to temperature is higher than that to rainfall. The lag model considering rainfall and temperature could effectively predict the next month＇s EVI（r = 0.84）.（2） Pests and drought disturbance reduced the sensitivity of vegetation response to climate.（3） The value of DEVI was significantly higher in pest years（0.045 ± 0.014） than in non-pest years（-0.003 ± 0.011）.
作者
曹雪佳
沈欣悦
沈亲
黄华国
CAO Xucjia;SHEN Xinyue;SHEN Qin;HUANG Huaguo(Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2018年第7期57-63,共7页
Journal of Central South University of Forestry & Technology
基金
国家林业公益性行业专项"重大森林虫灾监测预警的关键技术研究"(201404401)
国家自然科学基金项目(41571332)
