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Development of endemicity and conservation importance indices for tropical forests and the floral diversity assessment of Mt.Natoo in Benguet,Philippines
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作者 Johndale Rein T.BULLONG Jim P.SILVERIO +2 位作者 Joanna I.ALAFAG Maricel A.GURON Jones T.NAPALDET 《Journal of Mountain Science》 SCIE CSCD 2024年第3期786-804,共19页
The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using tradition... The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary ones.This shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the species.This study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the species.These indices were applied to Mt.Natoo,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of 42.90.Comparing these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower values.Thus,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical forests.Additionally,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in Mt.Nato-o.Majority are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate climate.These are important baseline information for conservation plans and monitoring of tropical mossy forests. 展开更多
关键词 Endemicity index conservation importance index Cordillera Central Range Floristic element Jaccard index of Similarity
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Combined Selection Index for New Yorkshire Dam Line with High Prolificacy
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作者 孙华 宋忠旭 +3 位作者 彭先文 李良华 董斌科 梅书棋 《Agricultural Science & Technology》 CAS 2013年第10期1443-1445,1461,共4页
The combined selection index used in the breeding of new Yorkshire dam line with high prolificacy according to breeding objects was formulated as /:2.272E- BVNB-0.056EBVDAYS. After 5 generations breeding, the two mai... The combined selection index used in the breeding of new Yorkshire dam line with high prolificacy according to breeding objects was formulated as /:2.272E- BVNB-0.056EBVDAYS. After 5 generations breeding, the two main selected traits such as total number of born and age at 100 kg weight was 12.17 piglets/litter and 165.18 d, respectively. The genetic improvements per generates was 0.156 and -2.198, respec- tively. The breeding objects of the new Yorkshire dam line with high prolificacy were basically reached. It indicated that the methods and index could be used in pig breeding. 展开更多
关键词 New Yorkshire dam line with high prolificacy Breeding objects Com- bined selection index
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A New Approach to Select Doubled Haploid Rice Lines under Salinity Stress Using Indirect Selection Index
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作者 Muhammad Fuad ANSHORI Bambang Sapta Purwoko +2 位作者 Iswari Saraswati Dewi Sintho Wahyuning Ardie Willy Bayuardi SUWARNO 《Rice science》 SCIE CSCD 2021年第4期368-378,I0024-I0026,共14页
This study determined the indirect selection index of doubled haploid(DH)rice using a multivariate analysis approach to select lines adaptive to salinity stress,comprising three experiments.The first experiment involv... This study determined the indirect selection index of doubled haploid(DH)rice using a multivariate analysis approach to select lines adaptive to salinity stress,comprising three experiments.The first experiment involved the selection of good agronomic characters in a field experiment conducted at an experimental station in Bogor,Indonesia.The second experiment involved salinity tolerance screening through hydroponic cultures using 0 and 120 mmol/L NaCl,conducted at a greenhouse in Bogor.The third experiment involved the validation of the indirect adaptability selection index(IASI)through a field experiment in Sukra(saline area).Field experiments followed a randomized complete block design(RCBD),whereas an RCBD nested factorial design was used for the greenhouse experiment.The first and second experiments used 56 DH lines and four check varieties with three replications.In the second experiment,Pokkali and IR29 varieties were also added as tolerant and sensitive checks of salinity,respectively.The third experiment used 28 selected DH lines,Inpari 29 and one sensitive DH line.The good agronomic index(GAI)was 0.465 yield+0.433 number of productive tillers+0.31 number of filled grains.This generated 24 DH rice lines with good agronomic traits.The salinity tolerance index(SaTI)was developed through the average of standardized salinity tolerance score and salinity selection index based on discriminant analysis.This generated 34 DH rice lines with good salinity stress tolerance.The IASI(IASI=GAI–SaTI)selected 28 DH rice lines adaptive to salinity stress and it was considered effective by Sukra validation. 展开更多
关键词 adaptability to salinity doubled haploid multivariate analysis RICE selection index
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The Grey Analysis, Kriging and Selection Index of Flower Yield in Rugosa Rose 被引量:6
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作者 LI Yan-yan FENG Zhen ZHAO Lan-yong MO Zhen-hua ZHANG Bao 《Agricultural Sciences in China》 CAS CSCD 2007年第12期1420-1425,共6页
The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa ro... The analysis of grey system, kriging interpolation, and integration selection index were employed to investigate the relationships between the flower yield/plant (FY) and 15 other quantitative traits of 20 rugosa rose cultivars. The result showed that: The grey relational grade (GRG) of the number of flowers/plant (NF), the number of branches/plant (NB), the width of floral bud (WB), and the weight/flower (WF) to the FY were larger (〉 0.5); FY improved with the increase of NF and NB. Moreover, the indirect selection of either trait could not achieve improvement of FY. It is necessary to improve FY by multi-trait selection. The integration selection index (ISI) equation of FY was established with the characters NF, NB, WB, and WF: I= 0.3187x1 - 318.6x2 + 670.1 x4 + 6.3xa, index heritability = 0.8014, selective response of the integration breeding value = 245.8811. This will provide a theoretic basis for the genetic breeding of rugosa rose. 展开更多
关键词 rugosa rose grey relational grade quantitative traits kriging interpolation index selection
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Smallholder Adoption of Soil and Water Conservation Practices in Northern Ghana
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《Journal of Agricultural Science and Technology(B)》 2012年第5期595-605,共11页
Both governmental and non-governmental organizations are engaged in the promotion of soil and water conservation practices in Northern Ghana, but adoption is believed to be low. This study thus examines the determinan... Both governmental and non-governmental organizations are engaged in the promotion of soil and water conservation practices in Northern Ghana, but adoption is believed to be low. This study thus examines the determinants of conservation practices adoption by farming households in the area. Data for the study were collected from 445 households located in 15 communities in Northern Ghana. Univariate, bivariate and multivariate probit models were used to analyse the decision to adopt six conservation practices in the area. Results show that the major determinants of adoption are plot and cropping characteristics such as location; and socio-economic and institutional variables such as number of contacts with extension officers, membership in farmer association and distance to major market. A policy implication of the study is the strengthening of extension service in the area to significantly boost conservation adootion. 展开更多
关键词 conservation practice MULTIVARIATE selectivity bias soil and water conservation Ghana.
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Using MaxEnt Model to Guide Marsh Conservation in the Nenjiang River Basin, Northeast China 被引量:6
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作者 WANG Zhiliang ZHANG Bai +1 位作者 ZHANG Xuezhen Tian Hongxu 《Chinese Geographical Science》 SCIE CSCD 2019年第6期962-973,共12页
Incorporating private and working lands into protected area networks could mitigate the isolation state of protected areas(PAs) and improve the efficiency of conservation.But how to select patches of land for conserva... Incorporating private and working lands into protected area networks could mitigate the isolation state of protected areas(PAs) and improve the efficiency of conservation.But how to select patches of land for conservation is still a troublesome issue.In this study, the MaxEnt model and irreplaceability index were applied to guide marsh conservation in the Nenjiang River Basin, Northeast China.According to the high accuracy of the MaxEnt model predictions(i.e., the average AUC value = 0.933), the Wuyuer River and Zhalong marshes in the downstream reaches of Wuyuer River are the optimal habitat for the Red-crowned crane and migratory waterfowls.There are 22 marsh patches selected by the patch irreplaceability index for conservation, of which 12 patches had been included in the current network of protected areas.The other 10 patches of marsh(amounting to 1096 km^2) far from human disturbances with high NDVI(up to 0.8) and close distance to water(less than 100 m), which are excluded from the existing network of PAs, should be implemented conservation easement programs to improve the protection efficiency of conservation.Specifically, the marshes at Taha, Tangchi, and Lamadian should be given priority for conservation and restoration to reintroduce migratory waterfowls, as this would lessen the current isolation state of the Zhalong National Nature Reserve. 展开更多
关键词 MAXENT MODEL IRREPLACEABILITY index MARSH conservation Red-crowned crane(Grus japonensis) Nenjiang River Basin
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Site-specific and seasonal variation in habitat use of Eurasian otters(Lutra lutra)in western China:implications for conservation 被引量:4
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作者 Qiao-Yun Wang Kai-Dan Zheng +4 位作者 Xue-Song Han Fang He Xiang Zhao Peng-Fei Fan Lu Zhang 《Zoological Research》 SCIE CAS CSCD 2021年第6期825-833,共9页
As a top predator,the Eurasian otter(Lutra lutra)is an indicator of healthy freshwater ecosystems and a flagship species for conservation.Once widespread in China,the species is now distributed mainly in the upper rea... As a top predator,the Eurasian otter(Lutra lutra)is an indicator of healthy freshwater ecosystems and a flagship species for conservation.Once widespread in China,the species is now distributed mainly in the upper reaches of the great rivers of western China.However,a lack of knowledge on local otter populations continues to hinder their conservation in China.Here,we conducted a detailed study on habitat use of Eurasian otters in Yushu City and Tangjiahe National Nature Reserve in western China using transect surveys.At both study sites,otters preferred to defecate on large rocks close to or protruding from the river and about 50 cm above the waterline.In Yushu,no spraints were found along the 5 km river bank section in the downtown area,with otters preferring sprainting sites with natural banks,riparian zones,and lower human population density.However,this pattern was not obvious at Tangjiahe,where river transformation and human disturbance are minor.Otter river use intensity was negatively correlated with elevation and human population density in Yushu in both seasons.In Tangjiahe,otter river use intensity was positively correlated with prey mass and flow rate and negatively correlated with human population in spring,but positively correlated with human population and negatively correlated with flow rate in autumn.These results reflect the flexible habitat use strategies of otters at different sites,underlining the necessity to study otters living in different regions and habitat types.We provide suggestions for river modification and call for more site-specific studies to promote otter conservation in China. 展开更多
关键词 Lutra lutra Sprainting site Habitat selection conservation Local scale
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Diversity,Distribution and Prioritization of Fodder Species for Conservation in Kullu District,Northwestern Himalaya,India 被引量:1
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作者 S. S. Samant Man Singh +1 位作者 Manohar Lal Shreekar Pant 《Journal of Mountain Science》 SCIE CSCD 2007年第3期259-274,共16页
In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribut... In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribution, utilization pattern, nativity, endemism, rarity, seasonality of availability, nutritive values, perceived economic values and pressure use index of livestock have not been studied. The present study attempts to enumerate 150 species of fodder representing trees (51 spp.), shrubs (54 spp.) and herbs (45 spp.). Poaceae (19 spp.) and Fabaceae (13 spp.) amongst families and Salix (6 spp.), Ficus, Clematis, and Desmodium (5 spp., each) amongst genera are rich in species. Maximum species were found in the 1801 ~ 2600 m zone, and the remaining two zones showed relatively low diversity. Out of the 150 species, 109 are used in summer, 5 winter and 36 throughout year. During rainy season, mostly grasses are used as fodder. Only 83 species are native to the Himalayan region, one species, Strobilanthus atropuroureus is endemic and 35 species are near endemic. The nutritive values of the fodder species were reviewed, and economic values and status of the species were also assessed. The pressure use index of the species was calculated on the basis of cumulative values of the utilization pattern, altitudinal distribution, availability, status, nativity and endemism. Amongst the species, Grewia oppositifoilia, Morus serrata, Indigofera heterantha, Quercus leucotrichphora, Ulmus villosa, U. wallichiana and Aesculus indica showed highest PUI indicating high preference and pressure. Season wise prioritization of the species for different altitudinal zones has been done. Appropriate strategy and action plan have been suggested for the conservation and management of fodder species. 展开更多
关键词 DIVERSITY utilization NATIVE ENDEMIC nutritive and economic value pressure use index PRIORITIZATION conservation Indian Himalayan Region
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On Solving TM_(0n) Modal Excitation in a Ka-Band Overmoded Circular Waveguide by the Conservation of Complex Power Technique 被引量:2
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作者 Feng Lan Xi Gao Zong-Jun Shi 《Journal of Electronic Science and Technology of China》 2009年第2期180-184,共5页
To measure the radiation properties of relativistic diffraction generator (RDG) in Ka-band, a TMon modal excitation model is established, which consists of an overmoded circular waveguide and a coaxial line feeding ... To measure the radiation properties of relativistic diffraction generator (RDG) in Ka-band, a TMon modal excitation model is established, which consists of an overmoded circular waveguide and a coaxial line feeding probe. Using the transverse E-field mode matching and the conservation of complex power technique (CCPT), we deduce the scattering matrix at coaxial line to coaxial line and coaxial line to circular waveguide junctions. Then using the overall cascaded junction scattering matrix, the numerical results for the reflection coefficient of the coaxial line and the power distribution of TMon multi-modal are presented. The numerical results are in agreement with HFSS simulation results and experimental results. The analysis shows that by choosing the appropriate position of coaxial line probe, the power proportion of the device operating mode excited in circular waveguide could be the largest. 展开更多
关键词 index Terms-Coaxial excitation conservation ofcomplex power technique overmoded waveguide relativistic diffraction generator.
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The Influence of Time Scale on the Quantitative Study of Soil and Water Conservation Effect of Grassland
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作者 Xiaoxia WU Zhujun GU 《Asian Agricultural Research》 2015年第4期69-74,共6页
Quantitative analysis of time scale effects is conducive to further understanding of vegetation water and soil conservation mechanism.Based on the observation data of the grass covered and bare soil( control) experime... Quantitative analysis of time scale effects is conducive to further understanding of vegetation water and soil conservation mechanism.Based on the observation data of the grass covered and bare soil( control) experimental plots located in Hetian Town,Changting County of Fujian Province from 2007 to 2010,the characteristics of 4 parameters( precipitation,vegetation,RE and SE) were analyzed at precipitation event,month,season,and annual scales,and then the linear regression models were established to describe the relationships between RE( SE)and its influencing factors of precipitation and vegetation. RE( SE) means the ratio of runoff depth( soil loss) of grass covered plot to that of the control plot. Results show that these 4 parameters presented different magnitude and variation on different time scales. RE and SE were relatively stable either within or among different time scales due to their ratios reducing the influence of other factors. The coupling of precipitation and vegetation led to better water conservation effect at lower RE( < 0. 3) at precipitation event scale as well as at season scale,while the water conservation effect was dominated by precipitation at slightly higher( 0. 3- 0. 4) and higher( > 0. 7) REs at precipitation event scale as well as at annual scale( R2> 0. 78). For the soil conservation effect,precipitation or / and vegetation was / were the dominated influence factor( s) at precipitation event and annual scales,and the grass LAI could basically describe the positive conservation effect( SE <1,R2> 0. 55),while the maximum 30 min intensity( I30) could describe the negative conservation effect more accurately( SE >1,R2> 0. 79). More uncertainties( R2≈0. 4) exist in the models of both RE and SE at two moderate time scales( month and season). Consequently,factors influencing water and soil conservation effect of grass present different variation and coupling characteristics on different time scales,indicating the importance of time scale at the study on water and soil conservation. 展开更多
关键词 Time SCALE LEAF area index Water conservation effe
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Study on Evaluation Method of Ecological Restoration for Soil and Water Conservation in Ningxia Hui Autonomous Region
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作者 Zhang Huwei Zhao Baoping +1 位作者 Ciren Nima Peng Qiong 《Meteorological and Environmental Research》 CAS 2014年第4期38-41,共4页
On the basis of deeply understanding the domestic existing evaluation method of ecological restoration for soil and water conservation, under the premise of analyzing characteristics of current commonly used evaluatio... On the basis of deeply understanding the domestic existing evaluation method of ecological restoration for soil and water conservation, under the premise of analyzing characteristics of current commonly used evaluation index of ecological restoration, based on the actual situation in Ningxia Hui Autonomous Region, taking objectivity, independence and operability as the principles, nine evaluation indexes were selected, and a set of comprehensive evaluation method of ecological restoration for water and soil conservation based on AHP was constructed. The hundred mark system corresponded with ecological restoration level, and the weight of each index in evaluation system was calculated according to comparison matrix constructed by frontline workers of soil and water conservation. The method could be used to determine difficult degree of restoration of the disturbed and destroyed ecosystem and the rationality of ecological restoration for soil and water conservation. 展开更多
关键词 Soil ancI water conservation Ecologicai restoration Analytic hierarchy process Evaluation index China
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Extraction,Utilization Pattern and Prioritization of Fuel Resources for Conservation in Manali Wildlife Sanctuary,Northwestern Himalaya
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作者 Man S.RANA Sakshi B.RANA S.S.SAMANT 《Journal of Mountain Science》 SCIE CSCD 2012年第4期580-588,共9页
Fuelwood is the main source of the energy in mountainous regions.Hence,annual wood consumption is very high.Information on fuelwood resources,and their extraction and availability is very scanty.Therefore,present stud... Fuelwood is the main source of the energy in mountainous regions.Hence,annual wood consumption is very high.Information on fuelwood resources,and their extraction and availability is very scanty.Therefore,present study was carried out to study the diversity of fuelwood species,annual collection,preference and availability of fuel species in the forests.Thirty four species(25 trees and 9 shrubs) were extracted for fuel by the inhabitants.Total collection and species preference was highest for Picea smithiana,Cedrus deodara,Indigofera heterantha,Pinus wallchiana and Sorbaria tomentosa,respectively.Resource use index indicating use pressure was highest for P.smithiana,C.deodara,I.heterantha and Abies pindrow,respectively.Besides native species,some non-native horticultural and agroforestry species such as Malus pumila,P.domestica,Celtis australis,etc.were also being used as fuel.Preferred species showed their availability in eight forest types whereas,population and regeneration status was poor.Therefore,immediate actions are suggested to sustain current and future demand of fuelwood.The afforestation of degraded,uncultivated and marginal lands through high quality and preferred fuel species might reduce pressure on wild and selective species. 展开更多
关键词 FUELWOOD Resource Use index COMMUNITIES conservation
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Selecting flagship species to solve a biodiversity conservation conundrum
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作者 Jie Qian Huifu Zhuang +6 位作者 Weikang Yang Yifeng Chen Shilong Chen Yanhua Qu Yuanming Zhang Yongping Yang Yuhua Wang 《Plant Diversity》 SCIE CAS CSCD 2020年第6期488-491,共4页
The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum.A project of the Chinese Academy of Sciences has concluded that progress can be made throu... The difficulty of effectively monitoring and managing the environment to conserve biodiversity is as yet an unsolved conundrum.A project of the Chinese Academy of Sciences has concluded that progress can be made through the use of flagship species selected using criteria drawn from conservation biology,ecosystem function,socio-economics,and cultural importance.Inclusion of the latter three criteria will help attract and maintain the commitment of the public to play full parts in carrying out any conservation measures needed.A system is proposed for scoring species to select those that are most suitable as flagships.This method can be used regardless of the size of the area chosen for attention,whether it is a region,a country,or a particular protected area. 展开更多
关键词 Flagship species selection criteria Biodiversity conservation Proposed program
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Assessing the performance of urban heritage conservation projects-influencing factors,aspects and priority weights
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作者 Sunena Abdul Huq Bimal Puthuvayi 《Built Heritage》 CSCD 2024年第1期46-66,共21页
Heritage conservation in urban areas involves complex systems often faced with the dilemmas of maintaining the built form's historical character,improving infrastructure,and managing development through stakeholde... Heritage conservation in urban areas involves complex systems often faced with the dilemmas of maintaining the built form's historical character,improving infrastructure,and managing development through stakeholder cooperation.At present,the performance of any conservation project is solely vested in conserving the built fabric.Evaluation tools for urban heritage conservation projects do not have provisions for measuring the subjective value of stakeholders who are part of the heritage setting.This study tries to identify and prioritise the factors that need to be considered when developing a conservation project performance assessment model for an urban heritage conservation project from the perspective of experts that can be further evaluated from the perspective of stakeholders.As these complex systems can be better viewed in the context of developing countries,the case of India is adopted.From a literature review,factors that contribute to the outcome of an urban heritage conservation project were identified and categorised into six aspects:the physical,social,economic,cultural,political,and continuity aspects.Through an expert survey,the factors that constituted each aspect were filtered using the feature selection method of correlation to avoid factors that may seem related.The factors under each aspect were ranked using a weighted average ranking method to identify the most prioritised factors determining the outcome of an urban heritage conservation project.The priority weights of the aspects were calculated using Saaty's analytic hierarchy process.The results show that the cultural aspect was the most important aspect,followed by the continuity aspect.The social and physical aspects were prioritised similarly,followed by the economic and political aspects.This study is distinctive because it identifies the influential factors that can help develop a conservation project performance assessment model for an urban heritage conservation project. 展开更多
关键词 heritage conservation urban conservation performance influential factors AHP filter-based feature selection
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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data 被引量:2
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作者 Yunping Chen Jie Hu +6 位作者 Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1164-1178,共15页
Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while r... Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities. 展开更多
关键词 ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data
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A preliminary site selection system for underground hydrogen storage in salt caverns and its application in Pingdingshan,China
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作者 Liangchao Huang Yanli Fang +6 位作者 Zhengmeng Hou Yachen Xie Lin Wu Jiashun Luo Qichen Wang Yilin Guo Wei Sun 《Deep Underground Science and Engineering》 2024年第1期117-128,共12页
Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns... Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns are recognized as ideal sites for pure hydrogen storage.Evaluation and optimization of site selection for hydrogen storage facilities in salt caverns have become significant issues.In this article,the software CiteSpace is used to analyze and filter hot topics in published research.Based on a detailed classification and analysis,a“four‐factor”model for the site selection of salt cavern hydrogen storage is proposed,encompassing the dynamic demands of hydrogen energy,geological,hydrological,and ground factors of salt mines.Subsequently,20 basic indicators for comprehensive suitability grading of the target site were screened using the analytic hierarchy process and expert survey methods were adopted,which provided a preliminary site selection system for salt cavern hydrogen storage.Ultimately,the developed system was applied for the evaluation of salt cavern hydrogen storage sites in the salt mines of Pingdingshan City,Henan Province,thereby confirming its rationality and effectiveness.This research provides a feasible method and theoretical basis for the site selection of UHS in salt caverns in China. 展开更多
关键词 analytic hierarchy process(AHP) evaluation index hydrogen storage salt cavern site selection
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Screen House Assessment of Cowpea [(Vigna unguiculata (L.)] Genotypes for Drought Tolerance Using Selection Indices
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作者 Sekou Armand Sanogo Sory Diallo +3 位作者 Teyioue Benoit Joseph Batieno Adejumobi Idris Ishola Nerbéwendé Sawadogo Daniel Nyadanu 《Agricultural Sciences》 CAS 2023年第4期457-473,共17页
Cowpea [Vigna unguiculata (L.)] is one of the most important arid legumes cultivated for pulse and forage production. Drought is one of the most damageable constraints to crop production impacting negatively food secu... Cowpea [Vigna unguiculata (L.)] is one of the most important arid legumes cultivated for pulse and forage production. Drought is one of the most damageable constraints to crop production impacting negatively food security. The potential of cowpea to address food security is well established. However, not much is known about the base index selection method in breeding cowpea for drought tolerance, which is important for yields. Consequently, the present study has been conducted to: 1) evaluate the yield performance of cowpea genotypes under artificial drought and well-watered condition, 2) ranke genotype performance using selection indices, and 3) assess relationship between agronomic traits and yield. The experiment was the 2 watering conditions laid out in a Randomized Complete Block Design (RCBD) with three replications. The experiment was carried out in pots under screen house at the Department of Horticulture at KNUST. The result showed that KPR1-96-73, Simbo, CZ06-4-16, Wilibaly and Agyenkwa were high yielding in well-water condition while Ghana Shoba, Sangaraka, Nketewade, Ghana Shoni and Korobalen were high yielding genotypes in water stress condition. The average yield reduction was 60.6% and 16% for grain and fodder yield respectively. The biplot displays revealed four groups among the genotypes tested which were based on their yielding capacity and drought tolerance. In cluster B high yielding and drought tolerant genotypes were identified, high yielding and drought susceptible have been identified in cluster A, low yielding and drought tolerant in cluster D, and lastly low yielding and drought susceptible in cluster C. Genotypes in cluster B were best due to the fact that it combines high yield and tolerance to drought. They were Ghana Shoni, Nketewade, Sangaraka and Ghana Shoba. These genotypes might be suitably employed in further drought tolerance breeding programs of cowpea. Significant relationships were observed between agronomic trait and yields under drought condition. 展开更多
关键词 Cowpea [Vigna unguiculata (L.)] DROUGHT selection index
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Variable Selection of Partially Linear Single-index Models 被引量:1
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作者 L U Yi-qiang HU Bin 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第3期392-399,共8页
In this article, we study the variable selection of partially linear single-index model(PLSIM). Based on the minimized average variance estimation, the variable selection of PLSIM is done by minimizing average varianc... In this article, we study the variable selection of partially linear single-index model(PLSIM). Based on the minimized average variance estimation, the variable selection of PLSIM is done by minimizing average variance with adaptive l1 penalty. Implementation algorithm is given. Under some regular conditions, we demonstrate the oracle properties of aLASSO procedure for PLSIM. Simulations are used to investigate the effectiveness of the proposed method for variable selection of PLSIM. 展开更多
关键词 variable selection adaptive LASSO minimized average variance estimation(MAVE) partially linear single-index model
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Automatic Variable Selection for Single-Index Random Effects Models with Longitudinal Data
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作者 Suigen Yang Liugen Xue 《Open Journal of Statistics》 2014年第3期230-237,共8页
We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method share... We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method shares some of the desired features of existing variable selection methods: the resulting estimator enjoys the oracle property;the proposed procedure avoids the convex optimization problem and is flexible and easy to implement. Moreover, we use the penalized weighted deviance criterion for a data-driven choice of the tuning parameters. Simulation studies are carried out to assess the performance of our method, and a real dataset is analyzed for further illustration. 展开更多
关键词 VARIABLE selection Single-index MODEL RANDOM Effects Longitudinal DATA
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基于相对联系数的区域水利高质量发展评价指标体系筛选方法 被引量:3
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作者 金菊良 周亮广 +4 位作者 王平 崔毅 吴成国 周戎星 袁康 《华北水利水电大学学报(自然科学版)》 北大核心 2024年第1期43-51,共9页
为综合判断在区域水利高质量发展目标、发展途径、发展条件相互作用下区域水资源-经济社会-生态环境复合系统不断协同优化的系统高质量发展水平状态,构建了由发展目标、发展途径和发展条件3个子系统组成的区域水利高质量发展初步评价指... 为综合判断在区域水利高质量发展目标、发展途径、发展条件相互作用下区域水资源-经济社会-生态环境复合系统不断协同优化的系统高质量发展水平状态,构建了由发展目标、发展途径和发展条件3个子系统组成的区域水利高质量发展初步评价指标体系。为定量分析初步评价指标体系的专家咨询信息,根据专家指标排序合理性模糊关系的取值区间特点提出了相对联系数,用相对联系数的平均集对势估计各专家指标排序合理性的权重,进而可得各指标重要性的专家综合排序值,据此筛选初步评价指标体系,构建了基于相对联系数的区域水利高质量发展评价指标体系筛选方法(SM-RCN)。SM-RCN在陕西省的应用结果表明:筛选后的指标体系汇聚了各专家对区域水利高质量发展主要影响指标的综合评判;SM-RCN可克服评价指标体系构建过程缺乏定量分析依据的不足,可识别不同专家、同一专家对不同评价方面的指标排序合理性的程度。该筛选方法在区域水利现代化、水资源空间均衡、水资源承载力等评价指标体系构建过程中具有应用前景。 展开更多
关键词 水利高质量发展 评价指标体系 指标筛选 系统结构 集对分析 相对联系数 平均集对势 陕西省
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