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831.
黑龙江省地震局在中国地震局黑龙江省委、省政府的领导下,致力建设一支高素质的防震减灾队伍,把握防震减灾工作服务于全省经济建设,努力开创防震减灾工作的新局面。近几年,全省的地震监测预报、震灾预防、紧急救援三大工作体系建设得到了快速发展。 相似文献
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本文讨论了低热通量条件下消防员防护服装热防护性能的测试原理和测试步骤。通过测试。分析了低热通量条件下消防员防护服装热防护性能的各种影响因素。 相似文献
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Xie Bin Luo Hang Tang Qing Du Jun Liu Zuohua Tao Changyuan 《Environmental science and pollution research international》2017,24(27):21761-21769
Environmental Science and Pollution Research - Black rock series (BRS) is of great potential for their plenty of valued oxides which include vanadium, iron, alumina and silica oxides, etc. BRS was... 相似文献
837.
Gömöryová E Střelcová K Fleischer P Gömöry D 《Environmental monitoring and assessment》2011,174(1-4):31-45
This study focused on the responses of soil microorganisms to different management regimes on disturbed windthrow areas. Microbial parameters potentially serving as indicators of environmental changes within a long-term monitoring of forest development after large-scale disturbance events were assessed. Basal and substrate-induced respiration, N mineralisation, catalase activity, microbial biomass as well as functional diversity based on Biolog assay were determined in soil samples from three disturbed plots and an undisturbed reference plot in the Tatra National Park (Slovakia) since 2006. A relative congruence of inter-annual trends of microbial activity indicators at all plots results from a common response of microbiota to changes of climate at the landscape level after forest stands were destroyed. While catalase activity and functional diversity proved to be useful indicators of temporal trends, microbial biomass seems to reflect different management regimes at the disturbed plots. 相似文献
838.
洞庭湖地区洪水灾害风险评估 总被引:4,自引:1,他引:3
综合当前国内外学者的理论及方法,以灾害风险系统是致灾因子、孕灾环境和承灾体共同作用的系统为基础,对洞庭湖地区进行洪水灾害风险评估,其中致灾因子用暴雨及以上降雨的加权频次来描述,孕灾环境用地形和河网密度来描述,承灾体脆弱性用内在脆弱性和抗灾救灾能力来描述。首先,对区域洪水致灾因子危险性进行评估;其次,对孕灾环境危险性进行评估;再次,对承灾体脆弱性进行评估;最后,对三者进行叠加分析得出洞庭湖地区洪水灾害风险区划图。其中,沿长江地区、湘江入湖地区和澧水河入湖地区洪水灾害风险高;其次是沿洞庭湖周围地区风险较高;洞庭湖地区边缘风险较低。 相似文献
839.
Xiaoguo Jiao Zhanqi Chen Jun Wu Hongyan Du Fengxiang Liu Jian Chen Daiqin Li 《Behavioral ecology and sociobiology》2011,65(2):325-332
Although the effects of male mating history on female reproductive output and longevity have been studied in insects, few
such studies have been carried out in spiders. In a mating system in which females are monandrous while males are polygynous,
females may incur the risk by mating with successful males that have experienced consecutive matings and suffer from the possible
depletion of sperm and/or associated ejaculates. Here, we examine the effects of male mating history on male courtship and
copulation duration, female reproductive fitness, and female adult longevity of the wolf spider, Pardosa astrigera. Results indicated that male mating frequency had little effect on their subsequent copulation success, and of 35 males tested,
about half of the males were able to copulate with five virgin females successively at an interval of 24 h. Male mating history
had little effect on their courtship duration. However, male mating history significantly affected male copulation duration,
female adult longevity, and reproductive output. Males that mated more frequently copulated longer and more likely failed
to cause their mates to produce a clutch, although there was no significant difference in the number of eggs laid and the
number of eggs hatched regardless of the first clutch or the second one. Multiple mating of male P. astrigera resulted in significant reduction in female adult longevity. Our results indicate that monandrous females mating with multiple-mated
males may incur substantial fitness costs. 相似文献
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