Tectonics and Seismicity of the Yarlung Tsangpo Grand Canyon Region

The Yarlung Tsangpo Grand Canyon region is located in the frontal zone of the eastern Himalayan syntaxis, where neo-tectonics and seismicity are intensive and closely related to each other. In the region, two sets of fault structures have developed, striking NNE-NE and NWW-NW, respectively. Investigation shows that they differ markedly in terms of scope, property, active times and intensity. The NWW-NW trending faults are large in size, and most are thrust and thrust strike-slip faults, formed in earlier times. The NEE-NE-strike faults are relatively small in size individually, with concentrated distribution, constituting the NNE-trending shear extensional fault zone, which is relatively younger with evident late Quaternary activities. Strong earthquakes occur mainly in the areas or zones of intensive differential movement of the Himalayas, e.g. along the deep and large fault zones around the crustal blocks. Most earthquakes of M≥7.0 are closely related to tectonics, where large-scale Holocene active faults are distributed with complicated fault geometry, or the faults of multiple directions intersect. Among them, earthquakes of M≥7.5 have occurred on the NW and NE-trending faults with a greater strike-slip component in the fault tectonic zones.     

Primary Quantitative Study on Earthquake Damage Extracted from Remote Sensing Imagery——A Case Study of Seismic Damage in the Urban Area of Dujiangyan due to the M_S8.0 Wenchuan Earthquake

The fast developing remote sensing techniques play an increasingly important role in earthquake emergency response, disaster survey and loss estimation. As there is a lack of quantitative studies on seismic damage based on remote sensing, its practicality in seismic disaster management has usually been questioned. The paper introduces the essential quantitative study idea, the concept of the remote sensing seismic damage index (DRS_I RS) and analysis models, demonstrates the seismic damage indices (DG_IC) of buildings obtained from ground surveying and its quantitative relation to DRS_I RS in Dujiangyan city, Sichuan Province, which was destroyed by the 2008 Wenchuan earthquake with M_S8.0. The primary results show that an obvious relationship exists between the DRS_I RS of buildings obtained from the high resolution satellite or aerial remote sensing images and DG_I C or the building collapse ratio obtained through ground survey, which suggests that the quantitative study on seismic damage based on remote sensing will provide an effective method for seismic damage survey and loss estimation.     

气象条件对作物品质和产量影响的试验研究

利用人工气候室试验研究了高温、高CO2浓度和水分胁迫等气象条件变化对农作物籽粒品质以及粮食安全供给的影响.结果表明:土壤水分胁迫有利于提高农作物籽粒的品质,而大气中CO2浓度升高并伴随高温出现不仅不利于农作物籽粒品质的提高,而且对作物在干旱条件下提高作物籽粒品质的能力有抑制作用,并将在大多数气候变化情景下对中国的粮食安全供给产生不利影响.     

分季节的太湖悬浮物遥感估测模型研究

根据1996-2002年无锡太湖监测站的水质资料分析,太湖悬浮物具有季节性特征,因而分季节的悬浮物估测模型比单一的模型可能更加适合用来估测太湖全年的悬浮物浓度.在分析太湖水体光谱特征的基础上,根据太湖悬浮物的季节性分布特征,使用春夏秋冬四季的Landsat TM/ETM图像和准同步的水质采样数据,建立了太湖分季节的悬浮物估算模型.结果表明:估测因子(B2 B3)/(B2/B3)在春、秋、冬三季都能很好地估测出悬浮物的浓度(R2＞0.52).夏季由于叶绿素的干扰性较大,悬浮物的估测效果不理想.冬季的估测效果最好(R2=0.81),模型为lnSS=14.656×(B2 B3)/(B2/B3) 1.661,其中,ln SS表示悬浮物取自然对数后的值,B2、B3为TM/ETM图像经过6S大气校正、3×3低通滤波后第2、3波段的反射率值.     

模拟低温下主产品种猕猴桃结果母枝冻害指标

越冬冻害是猕猴桃的主要气象灾害,为探讨低温对猕猴桃的伤害机理,建立猕猴桃越冬冻害指标体系,2020年12月—2021年2月利用MSX-2F霜箱系统模拟越冬期低温过程,采用组织褐变率、细胞伤害率等参数对结果母枝冻害特征进行定量描述,通过冻害指数与低温的Logistic关系模型,研究6个主栽品种结果母枝冻害特征.结果表明:...     

中国主产区玉米冠层对降水的截留研究

基于13个农业气象试验站2010—2017年逐日气象观测数据和玉米观测数据,采用针对玉米的截留模型,研究自然降雨条件下中国主产区玉米冠层截留及其变化规律.结果表明:在不同气候条件和生长状况下,玉米全生育期冠层截留差异较大.玉米冠层生长季平均截留量为4.3～23.5 mm,拔节到成熟期降水量≤70 mm时,截留量不足8 ...     

臭氧对水稻叶片伤害、光合作用及产量的影响

OTC- 1型农田开顶式气室 ,对水稻进行不同臭氧浓度处理的长期接触试验 ,结果表明 :当试验浓度超过 1 0 0× 1 0 - 9时将对水稻叶片造成直接伤害 ,从而使水稻的光合能力和产量降低。     

油蒿在高浓度CO2条件下对干旱胁迫的反应

采用人工模拟试验方法研究毛乌素沙地沙生植物群落的优势种－－油蒿在高浓度CO2条件下对土壤干旱胁迫的反应。结果表明，不同程度的土壤干旱胁迫使油蒿生长与生物量下降，随着干旱程度的加重而增加负面影响；大气中CO2浓度升高对油蒿的生长发育起到“施肥作用”；虽然在高浓度CO2条件下发生土壤干旱胁迫对油蒿的影响也是负效应，但CO2的“施肥效应”依然存在，“施肥效应”的生理机理是CO2浓度升高提高了光合作用速率。     

玉米抗低温促早熟药剂及使用技术试验研究初报

1引言低温冷害是东北地区主要农业气象灾害之一,严重的低温冷害年,造成的农作物受害面积大,减产幅度也大。近三十年来,全区性的几个严重低温冷害年,减产幅度都达20％以上。因而,低温冷害成为影响该区域粮食高产、稳产的主要因素。本项试验研究在总结近年来已有玉米抗低温助长剂应用情况基础上,通过新型药剂的研究和田间对比试验,研制出新型的,抗低温、助长、促早熟效果更好的更新换代产品。采用分期播种和药剂施用大田对比试验,对药剂的抗低温、助长、促早熟性能做出评价,并总结出有效的和低成本的施用技术。2药剂成份及性能与中…