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981.
基于MODIS和GPS的D-InSAR大气延迟改正 总被引:2,自引:0,他引:2
利用西安地区2006年7月至2009年7月7期GPS观测数据及相应的MODIS数据,分析MODIS水汽的校正模型.运用西安地区的Envisat数据和MODIS水汽数据进行D-InSAR大气延迟改正,实验结果表明:在大气状态变化缓慢时,利用MODIS数据对D-InSAR结果有一定的改善. 相似文献
982.
The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season. Regeneration diversity of Carex lasiocarpa community under different water levels was studied at two stages, recruitment and adult, in the Sanjiang Plain, Heilongjiang Province, China. The results showed that, at the two growing stages, important value of C. lasiocarpa population and species richness of the community decreased with the increasing water level, while the Simpson and Shannon-Wiener diversity indexes and Pielou evenness index increased. Under different water levels, community diversities were higher at the recruitment stage, while population important values of C. lasiocarpa were higher at the adult stage. Indexes in vegetation evaluation must be chosen prudentially for successful restoration and effective management of wetlands, and especially for wetland restoration, the optimal time should be selected according to the restoration objectives and costs. 相似文献
983.
LIAN Yi WANG Jie TU Gang REN Hongling SHEN Baizhu ZHI Keguang LI Shangfeng GAO Zongting 《中国地理科学(英文版)》2010,20(1):91-97
Interdecadal and interannual variations of saline-alkali land area in Qian’an County, Jilin Province, China were comprehensively
analyzed in this paper by means of satellite remote sensing interpretation, field flux observations and regional climate diagnosis.
The results show that on the interannual scale, the impact of climate factors accounts for 71.6% of the total variation of
the saline-alkali land area, and that of human activities accounts for 28.4%. Therefore the impact of climate factors is obviously
greater than that of human activities. On the interdecadal scale, the impact of climate factors on the increase of the saline-alkali
land area accounts for 43.2%, and that of human activities accounts for 56.8%. The impact of human activities on the variation
of saline-alkali land area is very clear on the interdecadal scale, and the negative impact of human activities on the environment
should not be negligible. Besides, changes in the area of heavy saline-alkali land have some indication for development of
saline-alkali land in Qian’an County. 相似文献
984.
Based on the NCEP (National Centers for Environmental Prediction) data, the relationship between the Sea Surface Temperature
Anomalies (SSTAs) in the North Pacific and the atmospheric circulation anomalies in January 2008 is analyzed in this study.
The SSTA mode most correlated with the Geopotential Height anomalies (GHAs) in January 2008 in the North Pacific exhibited
a basin-wide horseshoe pattern with a warm center in November 2007. This persistent SSTA pattern would induce positive GHAs
in the Aleutian Low area and East Asia and the northward extension of the West Pacific Subtropical High in January 2008 by
maximum diabatic heating in the atmosphere over the Kuroshio Oyashio Extension (KOE) area, leading to the occurence of the
circumpolar trough-ridge wave train anomaly in January 2008. 相似文献
985.
986.
987.
988.
储良广眼的砧穗不亲和现象在众多个体中呈现从亲和至不亲和的连续变化,随砧、穗周长差异的增大,不亲和症状表现突出。砧、穗周长比值与几个生长量指标存在显著相关。提出以砧/穗比作为衡量不亲和程度指标。靠接加砧结果表明对严重不亲和树出现的症状有较大的缓解。 相似文献
989.
叙述了氢及其同位素的性质,提出了几种制氢的方案,并通过电解水制氢和在切割上代替氧(乙炔的应用取得的成果,为氢取代矿物燃料而走进家庭的研究打下基础。氢可储存,氢也可在交通上作为燃料,并且没有污染,是未来的重要能源之一。 相似文献
990.
??GNSS??????????У??轫GNSS?????????????????????????????????????????GNSS???????????????????????????????????????????????????????????????????????????????????????????????????????????????е???????????????????????е????λ???ó????????????????????????????????????????????????????????????????о???GNSS???????????????????????????????????????????????????????????????????????????????????????????????????????????? 相似文献