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Numerical Analysis of Emergency River Restoration Scheme for Qingping Mega Debris Flow 被引量:2
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作者 CHEN Ri-dong LIU Xing-nian +1 位作者 HUANG Er GUO Zhi-xue 《Journal of Mountain Science》 SCIE CSCD 2013年第1期130-136,共7页
The mega debris flow occurred on August 13 th 2010 in Qingping town,China(hereafter called '8.13' Debris Flow) have done great damage to the local habitants as well as to the re-construction projects in the qu... The mega debris flow occurred on August 13 th 2010 in Qingping town,China(hereafter called '8.13' Debris Flow) have done great damage to the local habitants as well as to the re-construction projects in the quake-hit areas,and the channel-fill deposit problem caused by the debris flow was the most destructive.Moreover,it is of high possibility that an even severe deposit problem would reappear and result in worse consequences.In order to maximize risk reduction of this problem,relevant departments of the government established a series of emergency river restoration schemes,for which the numerical analysis is an important procedure to evaluate and determine the optimized one.This study presents a numerical analysis by applying a twodimensional debris flow model combined with a relevant water-sediment model to simulate the deposit during the progress of the debris flow,and to calculate and analyze the river flow field under both the present condition and different restoration conditions.The results show that the debris flow model,which takes the confluence of the Wenjia Gully to the main river into account,could simulate the deposit process quite well.In the reproduced debris flow from the simulation of the '8.13' Debris Flow,the original river flow path has switched to a relatively lower place just along the right bank with a high speed of near 7m.s-1 after being blocked by the deposit,which is highly hazardous.To prevent this hazard,a recommended scheme is derived through inter-comparison of different restoration conditions.It shows that the recommended scheme is able to reduce the water level and as well to regulate the flow path.Based on the given conditions of the mainstream and the tributary confluence for the simulated '8.13' Debris Flow,when encountering a debris flow with deposit volume less than 0.5 million m3,the river channel can endure a 20-year return flood;however,when the deposit volume increases to 2 million m3,the flood capacity of the river will be greatly impacted and the scheme becomes invalid.The recommended scheme supported by the present study has been applied to the emergency river restoration after this mega-debris flow. 展开更多
关键词 Flash flood Debris flow River restoration Numerical analysis Finite element method
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Genetic analysis of fertility restoration of Maxie cytoplasmic male sterility in rice(Oryza sativa L.)
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作者 ZHANG Xiaoguo ZHU Yingguo and MEI Qiming,College of Life Sci,Wuhan Univ,Wuhan 430072,China 《Chinese Rice Research Newsletter》 1996年第4期1-2,共2页
The genetic behavior of fertility restorationgenes of the cytoplasmic male sterile line Max-ie A was studied to facilitate the use ofMaweizhan male sterile cytoplasm.The F,F,and Fof Maxie A/Minhui 63 were grownin padd... The genetic behavior of fertility restorationgenes of the cytoplasmic male sterile line Max-ie A was studied to facilitate the use ofMaweizhan male sterile cytoplasm.The F,F,and Fof Maxie A/Minhui 63 were grownin paddy field,1993-1995.Meanwhile,someof the Fplants were testcrossed with themaintainer of Maxie A.The fertilities were 展开更多
关键词 Oryza sativa L Genetic analysis of fertility restoration of Maxie cytoplasmic male sterility in rice
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Genetics of Fertility Restoration in Cytoplasmic Male Sterile Pepper 被引量:3
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作者 WANG Li-hao ZHANG Bao-xi +5 位作者 AM Daubeze HUANG San-wen GUO Jia-zhen MAO Sheng-li A Palloix DU Yong-chen 《Agricultural Sciences in China》 CAS CSCD 2006年第3期188-195,共8页
Pepper hybrid seeds production using male sterility could lower cost by reducing time and labour, and increase the genetic purity of the F1 seeds. To investigate the genetics of fertility restoration of the Peterson c... Pepper hybrid seeds production using male sterility could lower cost by reducing time and labour, and increase the genetic purity of the F1 seeds. To investigate the genetics of fertility restoration of the Peterson cytoplasmic sterility in pepper, a doubled haploid population of 115 pepper lines obtained from anther culture of the F1 hybrid between Yolo Wonder (sterility maintainer line) and Perennial (fertility restorer line) and the parental lines were test-crossed by 77013A (a strict cytoplasmic-genic male sterile line). The fertility of the test-crossed lines was assessed in greenhouse and open field with the following three criteria: pollen index (PI, visual estimation of pollen amount per flower), pollen number (PN, pollen counting under microscope), and seed number (SN, the number of seeds per fruit in open pollination). Correlations between the each couple of criteria within, as well as between the cultivation methods ranged from 0.55 to 0.84. Analysis of variance showed that the genotype (DH line) and environment were the significant sources of variation of the fertility. Narrow sense of heritance of fertility restoration ranged from 0.38 to 0.92, depending on the criteria and environment. The distribution of the progeny was continuous between the parental genotypes indicating the quantitative inheritance of fertility restoration. Inferred from segregation according to Snape et al.(1984), the number of segregating genes was estimated to be that three to four genetic factors were involved in pollen traits (PI and PN) and five to eight genetic factors in seed production (SN). The heredity analysis of the CMS will be helpful for understanding of the genetic mechanism of the fertility restoration and the exploitation of the CMS in hybrid seed production. 展开更多
关键词 Capsicum annuum L. doubled haploids population cytoplasmic male sterility (CMS) fertility restoration genetic analysis
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Analysis of restoring gene in Heizhenmi
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作者 YANG Changdeng ZHAO Chengzhang QI Xiufang Wu Lianbin CNRRI,Hangzhou 310006,China 《Chinese Rice Research Newsletter》 1994年第2期8-9,共2页
The purple pigment is controlled by three domi-nant genes.According to the theory ofdominance-super dominance in Fgeneration, breeding purple black hybrid rice can be an effec-tive way to overcome lower yield and weak... The purple pigment is controlled by three domi-nant genes.According to the theory ofdominance-super dominance in Fgeneration, breeding purple black hybrid rice can be an effec-tive way to overcome lower yield and weak resist-ance to disease of purple black rice. 展开更多
关键词 analysis of restoring gene in Heizhenmi LINE GENE
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Spatio-temporal patterns of satellite-derived grassland vegetation phenology from 1998 to 2012 in Inner Mongolia, China 被引量:13
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作者 SHA Zongyao ZHONG Jialin +2 位作者 BAI Yongfei TAN Xicheng Jonathan LI 《Journal of Arid Land》 SCIE CSCD 2016年第3期462-477,共16页
Spatio-temporal variations of vegetation phenology, e.g. start of green-up season(SOS) and end of vegetation season(EOS), serve as important indicators of ecosystems. Routinely processed products from remotely sen... Spatio-temporal variations of vegetation phenology, e.g. start of green-up season(SOS) and end of vegetation season(EOS), serve as important indicators of ecosystems. Routinely processed products from remotely sensed imagery, such as the normalized difference vegetation index(NDVI), can be used to map such variations. A remote sensing approach to tracing vegetation phenology was demonstrated here in application to the Inner Mongolia grassland, China. SOS and EOS mapping at regional and vegetation type(meadow steppe, typical steppe, desert steppe and steppe desert) levels using SPOT-VGT NDVI series allows new insights into the grassland ecosystem. The spatial and temporal variability of SOS and EOS during 1998–2012 was highlighted and presented, as were SOS and EOS responses to the monthly climatic fluctuations. Results indicated that SOS and EOS did not exhibit consistent shifts at either regional or vegetation type level; the one exception was the steppe desert, the least productive vegetation cover, which exhibited a progressive earlier SOS and later EOS. Monthly average temperature and precipitation in preseason(February, March and April) imposed most remarkable and negative effects on SOS(except for the non-significant impact of precipitation on that of the meadow steppe), while the climate impact on EOS was found to vary considerably between the vegetation types. Results showed that the spatio-temporal variability of the vegetation phenology of the meadow steppe, typical steppe and desert steppe could be reflected by the monthly thermal and hydrological factors but the progressive earlier SOS and later EOS of the highly degraded steppe desert might be accounted for by non-climate factors only, suggesting that the vegetation growing period in the highly degraded areas of the grassland could be extended possibly by human interventions. 展开更多
关键词 phenological timing degradation harmonic analysis human activity climate restoration
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The net ecosystem services value in China's Mainland 被引量:3
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作者 Shixiong CAO Yujie LIU +2 位作者 Wei SU Xinyi ZHENG Zhongqi YU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第5期595-603,共9页
Protection of the ecological environment is an effective strategy for maintaining ecosystem health,improving provision of ecosystem services,and increasing human well-being.However,traditional calculations of the valu... Protection of the ecological environment is an effective strategy for maintaining ecosystem health,improving provision of ecosystem services,and increasing human well-being.However,traditional calculations of the value of ecosystem services(VES)provide weak guidance because they ignore the costs of these services,leading to economically inefficient strategies.To understand the difference between VES and the net ecosystem services value(NES,after subtracting costs from VES)and to improve evaluations of ecosystem services,we estimated NES for China's Mainland(including farmland,grassland,forest,and wetland).NES totaled 10.0×10~3RMB ha^(-1)yr^(-1)in 2014,which is only 35.1%of the corresponding VES.Grassland NES was–0.7×10~3RMB ha^(-1)yr^(-1),in contrast with a positive grassland VES.NES of farmland,grassland,forest,and wetland in2014 totaled 7.2×10^(12)RMB,accounting for 27.0%of China’s GNP.Recent Chinese planning based on VES emphasizes forest conservation and ignores the conservation of other important ecosystems,such as grassland,leading to a continuing loss of China’s natural capital.Due to regional differences in economic conditions,resource endowments,and geographical characteristics,VES and NES differ among regions.To maximize the ecological benefits from conservation,it is necessary to account for these differences by comparing strategies based on NES,thereby choosing projects that maximize both economic and ecological benefits.To maintain the ecological balance,ecological restoration and socioeconomic activities should account for the costs of providing ecosystem services.This is essential to minimize the costs and maximize the benefits of projects. 展开更多
关键词 Ecosystem services Cost analysis Environmental conservation Land management Ecological restoration
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