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Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate
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作者 Zhengchao Ren Lei Liu +1 位作者 Fang Yin Xiaoni Liu 《Forest Ecosystems》 SCIE CSCD 2024年第2期184-192,共9页
Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional pr... Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide. 展开更多
关键词 Potential natural vegetation Global warming vegetation classification Predicted model CSCS
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Echocardiographic predictors and associated outcomes of multiple vegetations in infective endocarditis:A pilot study
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作者 Ajay Kumar Mishra Kannu Bansal +6 位作者 Ibragim Al-Seykal Pradnya B Bhattad Anu Anna George Anil Jha Nitish Sharma Jennifer Sargent Mark J Kranis 《World Journal of Cardiology》 2024年第6期318-328,共11页
BACKGROUND Infective endocarditis(IE)is a life-threatening infection with an annual mortality of 40%.Embolic events reported in up to 80%of patients.Vegetations of>10 mm size are associated with increased embolic e... BACKGROUND Infective endocarditis(IE)is a life-threatening infection with an annual mortality of 40%.Embolic events reported in up to 80%of patients.Vegetations of>10 mm size are associated with increased embolic events and poor prognosis.There is a paucity of literature on the association of multiple vegetations with outcome.AIM To study the echocardiographic(ECHO)features and outcomes associated with the presence of multiple vegetations.METHODS In this retrospective,single-center,cohort study patients diagnosed with IE were recruited from June 2017 to June 2019.A total of 84 patients were diagnosed to have IE,of whom 67 with vegetation were identified.Baseline demographic,clinical,laboratory,and ECHO parameters were reviewed.Outcomes that were studied included recurrent admission,embolic phenomenon,and mortality.RESULTS Twenty-three(34%)patients were noted to have multiple vegetations,13(56.5%)were male and 10(43.5%)were female.The mean age of these patients was 50.Eight(35%)had a prior episode of IE.ECHO features of moderate to severe valvular regurgitation[odds ratio(OR)=4],presence of pacemaker lead(OR=4.8),impaired left ventricle(LV)relaxation(OR=4),and elevated pulmonary artery systolic pressure(PASP)(OR=2.2)are associated with higher odds of multiple vegetations.Of these moderate to severe valvular regurgitation(P=0.028),pacemaker lead(P=0.039)and impaired relaxation(P=0.028)were statistically significant.These patients were noted to have an increased association of recurrent admissions(OR=3.6),recurrent bacteremia(OR=2.4),embolic phenomenon(OR=2.5),intensive care unit stay(OR=2.8),hypotension(OR=2.1),surgical intervention(OR=2.8)and device removal(OR=4.8).Of this device removal(P=0.039)and recurrent admissions(P=0.017)were statistically significant.CONCLUSION This study highlights the associations of ECHO predictors and outcomes in patients with IE having multiple vegetations.ECHO features of moderate to severe regurgitation,presence of pacemaker lead,impaired LV relaxation,and elevated PASP and outcomes including recurrent admissions and device removal were found to be associated with multiple vegetations. 展开更多
关键词 ENDOCARDITIS ECHOCARDIOGRAPHY vegetations PREDICTORS OUTCOME
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儿童系统性红斑狼疮合并Libman-Sacks心内膜炎1例并文献复习 被引量:3
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作者 巴宏军 覃有振 +3 位作者 林约瑟 李轩狄 王慧深 王尧 《实用临床医学(江西)》 CAS 2019年第3期36-39,I0001,共5页
目的通过复习儿童系统性红斑狼疮(SLE)合并Libman-Sacks心内膜炎的临床及实验室特点、诊断及治疗方法,以期提高医师对该病的认识。方法结合相关文献对中山大学附属第一医院收治的1例儿童SLE合并Libman-Sacks心内膜炎的临床资料进行回顾... 目的通过复习儿童系统性红斑狼疮(SLE)合并Libman-Sacks心内膜炎的临床及实验室特点、诊断及治疗方法,以期提高医师对该病的认识。方法结合相关文献对中山大学附属第一医院收治的1例儿童SLE合并Libman-Sacks心内膜炎的临床资料进行回顾性分析。结果患儿,男,2岁5个月。以浮肿为首发症状,伴有皮肤瘀斑及肉眼血尿,按过敏性紫癜及紫癜肾炎治疗无好转。病程中有反复栓塞表现,血清抗磷脂抗体及狼疮相关抗体均阳性,肾脏病理为弥漫性节段增生性肾炎伴膜性狼疮性肾炎,免疫荧光:IgG+/-,IgM++,C3++,C1q++,FRA+,k+。炎症指标不高,多次血培养均阴性。心脏彩超提示左心增大,二尖瓣及主动脉瓣见赘生物。予强的松、他克莫司抑制免疫,以及抗凝、强心、利尿等治疗后好转。结论SLE合并Libman-Sacks心内膜炎容易误诊,主要应用糖皮质激素和免疫抑制剂、抗凝及调整心功能等对症治疗,预后依赖于早期诊断和早期治疗。 展开更多
关键词 系统性红斑狼疮 libman-sacks心内膜炎 儿童
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Purification Effects of Aquatic Vegetations on Lake Wetland Water Environment and Analysis of the Influencing Factors in Hongze Lake 被引量:3
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作者 赵洪波 吴睿 卡林 《Agricultural Science & Technology》 CAS 2012年第1期211-216,共6页
[Objective] To study the purification effect of plant community on wetland water environment in Hongze Lake, and to provide references to the ecological restoration of this area. [Methed] The typical lakeside zone of ... [Objective] To study the purification effect of plant community on wetland water environment in Hongze Lake, and to provide references to the ecological restoration of this area. [Methed] The typical lakeside zone of Hongze Lake Wetland National Nature Reserve was taken as the study area. Through the field survey based on environmental characteristics of aquatic areas and non-aquatic areas, combined with laboratory test, the content changes of nutrients (N and P), COD (chemical oxygen demand) and SD (transparency) levels in the water body of lake wetland were measured; the purification effect of the lake wetland ecosystem in the growth process of aquatic vegetation was quantitatively analyzed, and possible influ- encing factors were discussed. [Result] Aquatic vegetation could remove the TN, TP, COD, Chla in wetland water environment and had obvious effects on the changes of SD content. Competition between aquatic plants can inhibit the growth of algae and relieve the eutrophication of water body. [Conclusion] This study provided theoretical basis for ecological restoration and enhancement of self-purification capability in the lakeside zone of Hongze Lake. 展开更多
关键词 Aquatic vegetation Water environment Purification effect Influencing factors
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超声心动图诊断Libman-Sacks赘生物1例
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作者 孙娟娟 王吴刚 王志斌 《中国医学影像技术》 CSCD 北大核心 2018年第11期1749-1749,共1页
图1 主动脉瓣Libman-Sacks赘生物 A.胸骨旁左心室长轴切面示主动脉瓣右冠瓣及无冠瓣明显增厚(箭);B.心尖三腔心切面示舒张期主动脉瓣重度反流(箭)患者男,66岁,因“胸闷憋气4年,加重3个月”入院;既往有先天性心脏病房间隔缺损病史、癫痫... 图1 主动脉瓣Libman-Sacks赘生物 A.胸骨旁左心室长轴切面示主动脉瓣右冠瓣及无冠瓣明显增厚(箭);B.心尖三腔心切面示舒张期主动脉瓣重度反流(箭)患者男,66岁,因“胸闷憋气4年,加重3个月”入院;既往有先天性心脏病房间隔缺损病史、癫痫史12年。查体:体温37℃,血压157 mmHg/61 mmHg,双下肢水肿。血常规:白细胞5.60×10 9/L,血红蛋白52.00 g/L,血小板31.00×10 9/L。尿常规示尿蛋白及隐血阳性,尿蛋白排泄量1.33 g/24 h,肌酐278.20μmol/L,尿素氮19.00 mmol/L。免疫学检查:抗核抗体阳性,滴度1∶10 000;抗ds-DNA抗体阳性;抗着丝点抗体阳性;补体C3 0.23 g/L,C4<0.06 g/L。血培养细菌阴性。超声心动图示主动脉瓣叶明显增厚(图1A),可见约1.2 cm×1.2 cm的中等偏强回声附着,瓣叶关闭不良,舒张期可见重度反流(图1B);主动脉瓣开放受限,收缩期峰值流速4.30 m/s,峰值压差73 mmHg,平均压差42 mmHg;房间隔可见1.0 cm×1.2 cm缺损。超声诊断:主动脉瓣赘生物,房间隔缺损(中央型)。临床最终诊断为系统性红斑狼疮(systemic lupus erythematosus,SLE)并Libman-Sacks赘生物。 展开更多
关键词 超声心动描记术 libman-sacks赘生物
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系统性红斑狼疮伴三尖瓣Libman-Sacks赘生物1例 被引量:1
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作者 王永槐 张妍 +2 位作者 马春燕 关正宇 杨军 《中国医学影像技术》 CSCD 北大核心 2013年第5期849-849,共1页
患者女,40岁,患系统性红斑狼疮(systemic lupus erythematosus,SLE)5年,因“发热、气短伴关节痛”入院。查体:体温39.0℃,脉搏94次/分,血压107mmHg/76mmHg,三尖瓣区闻及2/6级收缩期杂音。免疫学检查:C30.58g/L,C40.... 患者女,40岁,患系统性红斑狼疮(systemic lupus erythematosus,SLE)5年,因“发热、气短伴关节痛”入院。查体:体温39.0℃,脉搏94次/分,血压107mmHg/76mmHg,三尖瓣区闻及2/6级收缩期杂音。免疫学检查:C30.58g/L,C40.09g/L, 展开更多
关键词 红斑狼疮 系统性 Libman—Sacks赘生物 超声心动描记术
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Libman-Sacks心内膜炎的超声心动图表现及临床特征分析 被引量:3
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作者 梁彗莉 王涛 +3 位作者 陈昕 李潭 杨军 马春燕 《中国医科大学学报》 CAS CSCD 北大核心 2021年第6期540-543,共4页
目的回顾性分析系统性红斑狼疮(SLE)及抗磷脂抗体综合征(APS)伴Libman-Sacks心内膜炎的超声心动图表现及临床特征。方法选择2016年1月至2020年12月于我院就诊经胸超声心动图(TTE)或经食管三维超声(3D-TEE)诊断为Libman-Sacks心内膜炎的2... 目的回顾性分析系统性红斑狼疮(SLE)及抗磷脂抗体综合征(APS)伴Libman-Sacks心内膜炎的超声心动图表现及临床特征。方法选择2016年1月至2020年12月于我院就诊经胸超声心动图(TTE)或经食管三维超声(3D-TEE)诊断为Libman-Sacks心内膜炎的23例SLE患者作为研究对象,对其超声表现及临床特征进行回顾性分析。根据是否合并APS进行分组,对比2组患者的超声及临床表现。结果23例患者中,心内膜炎累及二尖瓣15例(65.2%),主动脉瓣5例(21.7%),三尖瓣1例(4.3%),同时累及二尖瓣及主动脉瓣2例(8.7%)。单纯SLE组14例,瓣膜中度及以上反流2例(14.3%);合并APS组9例,其中合并脑血管栓塞3例(33.3%),瓣膜中度及以上反流4例(44.4%)。结论TTE结合3D-TEE能够早期发现并精确显示赘生物的位置、大小及形态;合并APS的患者瓣膜病变程度更重,脑血管栓塞事件发生率更高。 展开更多
关键词 libman-sacks心内膜炎 系统性红斑狼疮 抗磷脂抗体综合征 超声心动图
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A Fractal Method of Estimating Soil Structure Changes Under Different Vegetations on Ziwuling Mountains of the Loess Plateau,China 被引量:14
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作者 ZHAO Shi-wei SU Jing +3 位作者 YANG Yong-hui LIU Na-na WU Jin-shui SHANGGUAN Zhou-ping 《Agricultural Sciences in China》 CAS CSCD 2006年第7期530-538,共9页
Fractal method is a new method to estimate soil structure. It has been shown to be a useful tool in studies related to physical properties of soil as well as erosion and other hydrological processes. Fractal dimension... Fractal method is a new method to estimate soil structure. It has been shown to be a useful tool in studies related to physical properties of soil as well as erosion and other hydrological processes. Fractal dimension was used to study the soil structure in soil at different stages of vegetative succession on the Ziwuling Mountains. The land use and vegetation types included cultivated land, abandoned land, grassland, two types of shrub land, and three types of forests. The grassland, shrub land, and forested areas represented a continuum in vegetative succession that had occurred naturally, as the land was abandoned in 1862. Disturbed and undisturbed soil samples were collected from ten vegetation types from depths of 0-10, 10-20, and 20-30 cm on the Ziwuling Mountains, at a site with an elevation of about 1 500 m. Particle size distribution was determined by the pipette method and aggregate size distribution was determined by wet sieving. The results were used to calculate the particle and aggregate fractal dimension. The results showed that particle and aggregate fractal dimensions varied between vegetation types. There was a positive correlation between the particle fractal dimension and the weight of particles with diameter 〈 0.001 mm, but no relationship between particle fractal dimension and the other particle size classes. Particle fractal dimension was lower in vegetated soils compared to cropland and there was no consistent relationship between fractal dimension and vegetation type. Aggregate fractal dimension was positively correlated with the weight of 〉 0.25 mm aggregates. Aggregate fractal dimension was lower in vegetated soils compared with cropland. In contrast to particle fractal dimension, aggregate fractal dimension described changes in soil structure associated with vegetative succession. The results of this study indicate that aggregate fractal dimension is more effective in describing soil structure and function compared with particle fractal dimension. 展开更多
关键词 soil fractal dimension soil particle soil aggregate vegetation type Ziwuling Mountains
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Fractions and Bioavailability of Soil Inorganic Phosphorus in the Loess Plateau of China under Different Vegetations 被引量:6
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作者 WEI Xiaorong SHAO Mingan +2 位作者 SHAO Hongbo GAO Jianlun XU Gang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第1期263-270,共8页
Plants play an important role in soil phosphorus nutrition. However, the effect of plants on phosphorus nutrition in soils of the Loess Plateau of China is not well understood. This study was conducted to reveal the r... Plants play an important role in soil phosphorus nutrition. However, the effect of plants on phosphorus nutrition in soils of the Loess Plateau of China is not well understood. This study was conducted to reveal the relationships between plants and phosphorus' fractions and availability in the Loess Plateau of China. Twenty-two plant communities were surveyed and soil samples under different plant canopies were collected for the determination of soil properties and inorganic phosphorus fractionation. The results showed that Leguminosae and Lilaceae reduced pH and increased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies, while Labiatae and Rosaceae increased pH and decreased organic matter, cation exchange capacity, total and Olsen phosphorus in soils under their canopies. The contents of Ca2P, CasP, AI-P and Fe-P were highly related with soil Oisen phosphorus. They were all higher in soils under Leguminosae and Lilaceae and lower in softs under Labiatae and Rosaceae. The results of this study indicate that Leguminosae and Lilaceae improved phosphorus nutrition in soils, yet Labiatae and Rosaceae impeded the improvement of phosphorus nutrition in soils under their canopies, which will be of more help to instruct vegetation restoration in the region and provide information for soil development. 展开更多
关键词 BIOAVAILABILITY FRACTION inorganic phosphorus vegetATION soil development Loess Plateau
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Impact of Tourism Interference on Vegetations in Xijing Mountain
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作者 杨少华 侯平 《Journal of Landscape Research》 2010年第12期32-36,40,共6页
[Objective] Taking Xijing Mountain for example,this study investigates characteristics of roadside plant communities and width changes of trampled vegetations by the tourist road,analyzes influence of tourism activiti... [Objective] Taking Xijing Mountain for example,this study investigates characteristics of roadside plant communities and width changes of trampled vegetations by the tourist road,analyzes influence of tourism activities on environment.[Method] Characteristics of roadside plant communities are studied by applying species diversity index,coverage and other such indexes;from the bottom to the top of Xijing Mountain,investigation objects are selected along the tourist road to measure the trampled width of vegetations.[Result] Characteristics of plant communities,trampled vegetations are both closely related to the design of tourist road.[Conclusion] Suggestions are proposed for the design of tourist road. 展开更多
关键词 Plant COMMUNITY characteristics WIDTH of trampled vegetations Design of TOURIST road
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Velocity distribution of flow with submerged flexible vegetations based on mixing-length approach 被引量:2
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作者 槐文信 韩杰 +3 位作者 曾玉红 安翔 钱忠东 Yu-lu LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期343-351,共9页
By choosing a PVC slice to simulate flexible vegetation, we carried out experiments in an open channel with submerged flexible vegetation. A 3D acoustic Doppler velocimeter (micro ADV) was used to measure local flow... By choosing a PVC slice to simulate flexible vegetation, we carried out experiments in an open channel with submerged flexible vegetation. A 3D acoustic Doppler velocimeter (micro ADV) was used to measure local flow velocities and Reynolds stress. The results show that hydraulic characteristics in non-vegetation and vegetation layers are totally different. In a region above the vegetation, Reynolds stress distribution is linear, and the measured velocity profile is a classical logarithmic one. Based on the concept of new-riverbed, the river compression parameter representing the impact of vegetation on river is given, and a new assumption of mixing length expression is made. The formula for time-averaged velocity derived from the expression requires less parameters and simple calculation, and is useful in applications. 展开更多
关键词 flexible vegetation PVC slice micro ADV mixing-length approach streamwise velocity distribution Reynolds stress river compression parameter
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SLE继发抗磷脂抗体综合征合并Libman-Sacks心内膜炎一例 被引量:2
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作者 卢丽娟 黄勤 《新医学》 2021年第1期70-73,共4页
临床部分SLE患者可继发抗磷脂抗体综合征(APS),但同时合并非细菌性心内膜炎的患者则较为罕见。该文报道1例SLE继发APS合并Libman-Sacks心内膜炎患者的诊治过程。该患者入院前有发热、关节痛、咽痛和皮疹,入院后UCG示二尖瓣前叶赘生物形... 临床部分SLE患者可继发抗磷脂抗体综合征(APS),但同时合并非细菌性心内膜炎的患者则较为罕见。该文报道1例SLE继发APS合并Libman-Sacks心内膜炎患者的诊治过程。该患者入院前有发热、关节痛、咽痛和皮疹,入院后UCG示二尖瓣前叶赘生物形成,查狼疮抗体、抗磷脂抗体、狼疮样抗凝物试验阳性,经抗感染治疗后病情未缓解,后患者突发头晕、口周麻木、构音不清、吞咽困难,查头颅MRI见一新发的延髓梗死灶。结合患者临床表现、体征及辅助检查,诊断为APS,Libman-Sacks心内膜炎,延髓梗死,SLE。予免疫抑制、免疫调节、低分子肝素抗凝等治疗后患者病情好转出院。该例的诊治提示,在UCG发现赘生物时,不仅要考虑感染性心内膜炎,同时需要考虑SLE继发APS可能,尤其是对于既往无明确心瓣膜病病史的年轻女性,早期诊断APS合并Libman-Sacks心内膜炎,并给予个体化抗凝治疗,可取得良好疗效。 展开更多
关键词 抗磷脂抗体综合征 系统性红斑狼疮 libman-sacks心内膜炎 抗凝治疗 感染性心内膜炎 鉴别诊断
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GbLMI1 over-expression improves cotton aboveground vegetative growth 被引量:1
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作者 Zhili Chong Yunxiao Wei +7 位作者 Kaili Li Muhammad Aneeq Ur Rahman Chengzhen Liang Zhigang Meng Yuan Wang Sandui Guo Liangrong He Rui Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3457-3467,共11页
Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have show... Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have shown that LMI1(LATE MERISTEM IDENTITY1)is the main gene regulating leaf shape.In this study,the LMI1 gene was inserted into the 35S promoter expression vector,and cotton plants overexpressing LMI1(OE)were obtained through genetic transformation.Statistical analysis of the biological traits of the T_(1) and T_(2) populations showed that compared to the wild type(WT),OE plants had significantly larger leaves,thicker stems and significantly greater dry weight.Furthermore,plant sections of the main vein and petiole showed that the numbers of cells in those tissues of OE plants were significantly greater.In addition,RNA-seq analysis revealed the differential expression of genes related to gibberellin synthesis and NAC gene family(genes containing the NAC domain)between the OE and WT plants,suggesting that LMI1 is involved in secondary wall formation and cell proliferation,which promotes stem thickening.Moreover,Gene Ontology(GO)analysis revealed enrichment in the terms of calcium ion binding,and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis showed enrichment in the terms of fatty acid degradation,phosphatidylinositol signal transduction system,and c AMP(cyclic adenosine monophosphate)signal pathway.These results suggested that LMI1 OE plants are responsive to gibberellin hormone signals,and have altered messenger signals(c AMP,Ca^(2+))which amplify this function,to promote stronger aboveground vegetative growth.This study found the LMI1 greatly increased the vegetative growth in cotton,which is the basic requirement for higher yield. 展开更多
关键词 LMI1 over-expressing COTTON vegetative growth
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Floral Diversity of Abandoned Mansions and the Influence of Soil Properties on These Unique Vegetations
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作者 Md. Tahidul Islam Md. Mahadiy Hasan +2 位作者 Md. Ashikur Rahman Laskar Subroto K. Das Tania Sultana 《American Journal of Plant Sciences》 2021年第10期1559-1600,共42页
Abandoned land and mansions are always a matter of curiosity to the human beings. They are treated as haunted places in many societies. In the present research, three decrepit abandoned mansions from the southern Bang... Abandoned land and mansions are always a matter of curiosity to the human beings. They are treated as haunted places in many societies. In the present research, three decrepit abandoned mansions from the southern Bangladesh were investigated to measure their floral diversity, physico-chemical properties of soil and the soil-plant interrelationship which is responsible for the diversification of wild flora within the regions. From Shannon and Simpson diversity indexes, it can be deducted that the floral diversity within the abandoned mansions ha</span><span style="font-family:"">s</span><span style="font-family:""> a<span style="color:red;"> </span>positive relationship with their territory size. The high values of Marg<span>alef’s and Menhinick’s species richness indexes confirmed that these areas are a rich source of a large number of plant species. A great variation in soil physico-chemical properties has been observed during the analysis. Soil organic matter, nitrogen, phosphorus, potassium & moisture contents were varied significantly from one quadrat to another in every site. Biplot analysis showed that the distribution of plant species in abandoned mansions </span></span><span style="font-family:"">is</span><span style="font-family:""> primarily determined by the organic matter, pH, moisture and potassium contents of soil. As t</span><span style="font-family:"">hese factors were present in versatile distribution within the studied regions, a great number of plants can grow in the same area simultaneously. So these areas should be protected from human intervention to proce</span><span style="font-family:"">ss</span><span style="font-family:""> natural selection and in situ conservation of plant species. 展开更多
关键词 Floral Diversity Abandoned Area Soil Properties vegetATION
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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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Feature extraction and analysis of reclaimed vegetation in ecological restoration area of abandoned mines based on hyperspectral remote sensing images
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作者 MAO Zhengjun WANG Munan +3 位作者 CHU Jiwei SUN Jiewen LIANG Wei YU Haiyong 《Journal of Arid Land》 SCIE CSCD 2024年第10期1409-1425,共17页
The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric ... The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric scattering and directly reflect the vegetation parameter information.In this study,the abandoned mining area in the Helan Mountains,China was taken as the study area.Based on hyperspectral remote sensing images of Zhuhai No.1 hyperspectral satellite,we used the pixel dichotomy model,which was constructed using the normalized difference vegetation index(NDVI),to estimate the vegetation coverage of the study area,and evaluated the vegetation growth status by five vegetation indices(NDVI,ratio vegetation index(RVI),photochemical vegetation index(PVI),red-green ratio index(RGI),and anthocyanin reflectance index 1(ARI1)).According to the results,the reclaimed vegetation growth status in the study area can be divided into four levels(unhealthy,low healthy,healthy,and very healthy).The overall vegetation growth status in the study area was generally at low healthy level,indicating that the vegetation growth status in the study area was not good due to short-time period restoration and harsh damaged environment such as high and steep rock slopes.Furthermore,the unhealthy areas were mainly located in Dawukougou where abandoned mines were concentrated,indicating that the original mining activities have had a large effect on vegetation ecology.After ecological restoration of abandoned mines,the vegetation coverage in the study area has increased to a certain extent,but the amplitude was not large.The situation of vegetation coverage in the northern part of the study area was worse than that in the southern part,due to abandoned mines mainly concentrating in the northern part of the Helan Mountains.The combination of hyperspectral remote sensing data and vegetation indices can comprehensively extract the characteristics of vegetation,accurately analyze the plant growth status,and provide technical support for vegetation health evaluation. 展开更多
关键词 hyperspectral remote sensing abandoned mine ecological restoration vegetation growth status vegetation index vegetation coverage
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Taxonomic Study of Five Parasitic Polypores of the Hymenochaetaceae Family of TIN Vegetation in Western Burkina Faso
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作者 Kusiélé Somda Andjièrèyir Nankoné Samson +4 位作者 Nana R. Sylvie Bakiono Benovana Sédégo K. Jean Edouard Dabiré Kounbo Sanon Elise 《American Journal of Plant Sciences》 CAS 2024年第6期441-454,共14页
The aim of this work is to inventory and study the lignicolous parasitic macrofungi of the Tin plant formation. The mycological outings from July to September 2018 and 2019, collected forty-four (44) basidiomes throug... The aim of this work is to inventory and study the lignicolous parasitic macrofungi of the Tin plant formation. The mycological outings from July to September 2018 and 2019, collected forty-four (44) basidiomes through a random sampling device over an area of 40,000 m2 including 1000 m long by 40 m2 wide. The standard methods and techniques used in mycology for taxonomic studies were used to describe and classify the carpophores collected in three families: Hymenochaetaceae, Ganodermataceae and Polyporaceae, into eight genera: Onnia (4.55%), Amauroderma (4.55%), Ganoderma (20.45%), Phellinus (52.27%), Inonotus (4.55%), Phellinopsis (6.82%), Grammothele (2.27%) and Trametes (4.55%). The genera Phellinus and Ganoderma were the most abundant. Finally, eight species were identified: Inonotus cf. ochroporus, Inonotus cf. pachyphloeus, Phellinus cf. cryptarum, Phellinus cf. hartigii, Phellinus cf. hippophaecola;Phellinus cf. robustus, Phellinus cf. igniarius, et Amauroderma cf. fasciculatum. Seven fungal species belong to the family Hymenochaetaceae and only the species Amauroderma cf. fasciculatum is a Ganodermataceae. However, all these fungal species are shown to be parasites of trunks and/or branches of the following woody: Parkia biglobosa (50%), Anogeissus leiocarpus (25%), Annona senegalensis (12.5%) and Mangifera indica (12.5%). Authors attest that the presence of phytoparasitic polypores in a plant formation is an indicator of aging hence the urgency to put in place the appropriate measures to safeguard and restore Tin’s plant formation. 展开更多
关键词 Identification MACROFUNGI Lignicolous Parasites vegetATION TIN Burkina Faso
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Response of vegetation variation to climate change and human activities in the Shiyang River Basin of China during 2001-2022
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作者 SUN Chao BAI Xuelian +2 位作者 WANG Xinping ZHAO Wenzhi WEI Lemin 《Journal of Arid Land》 SCIE CSCD 2024年第8期1044-1061,共18页
Understanding the response of vegetation variation to climate change and human activities is critical for addressing future conflicts between humans and the environment,and maintaining ecosystem stability.Here,we aime... Understanding the response of vegetation variation to climate change and human activities is critical for addressing future conflicts between humans and the environment,and maintaining ecosystem stability.Here,we aimed to identify the determining factors of vegetation variation and explore the sensitivity of vegetation to temperature(SVT)and the sensitivity of vegetation to precipitation(SVP)in the Shiyang River Basin(SYRB)of China during 2001-2022.The climate data from climatic research unit(CRU),vegetation index data from Moderate Resolution Imaging Spectroradiometer(MODIS),and land use data from Landsat images were used to analyze the spatial-temporal changes in vegetation indices,climate,and land use in the SYRB and its sub-basins(i.e.,upstream,midstream,and downstream basins)during 2001-2022.Linear regression analysis and correlation analysis were used to explore the SVT and SVP,revealing the driving factors of vegetation variation.Significant increasing trends(P<0.05)were detected for the enhanced vegetation index(EVI)and normalized difference vegetation index(NDVI)in the SYRB during 2001-2022,with most regions(84%)experiencing significant variation in vegetation,and land use change was determined as the dominant factor of vegetation variation.Non-significant decreasing trends were detected in the SVT and SVP of the SYRB during 2001-2022.There were spatial differences in vegetation variation,SVT,and SVP.Although NDVI and EVI exhibited increasing trends in the upstream,midstream,and downstream basins,the change slope in the downstream basin was lower than those in the upstream and midstream basins,the SVT in the upstream basin was higher than those in the midstream and downstream basins,and the SVP in the downstream basin was lower than those in the upstream and midstream basins.Temperature and precipitation changes controlled vegetation variation in the upstream and midstream basins while human activities(land use change)dominated vegetation variation in the downstream basin.We concluded that there is a spatial heterogeneity in the response of vegetation variation to climate change and human activities across different sub-basins of the SYRB.These findings can enhance our understanding of the relationship among vegetation variation,climate change,and human activities,and provide a reference for addressing future conflicts between humans and the environment in the arid inland river basins. 展开更多
关键词 vegetation variation climate change land use change normalized difference vegetation index(NDVI) enhanced vegetation index(EVI) Shiyang River Basin
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Cosmetic or Dietary Vegetable Oils Sampled in the Cameroonian Market May Not Expose Consumers to Lipid Oxidation Products Generating Oxidative Stress and Inflammation
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作者 Ferdinand Kouoh Elombo Erika Van Damme +5 位作者 Clara Delepine David Depraetere Ludovic Chaveriat Paul Lunga Keilah Nico Fréderic Njayou Patrick Martin 《American Journal of Plant Sciences》 CAS 2024年第3期193-202,共10页
Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ ... Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ derivatives. However, their chemical and physical properties can be modified by the mode of their extraction, storage and distribution. These modifications might negatively affect the nutritional quality of the oils. The goals of this study were to: sample different vegetable oils for cosmetic or dietary use marketed in Cameroon, and verify purity and oxidation states of each kind of oil through determination of its acidity, iodine, peroxide, saponification, refractive indexes and the conformity of the labeling. The carotene content, the level of polar components and specific absorbance were also determined. As the result, six oils namely palm, palm kernel, coconut, black cumin, peanut and shea butter were collected. Apart from labeling, chemicals and physicals parameters analyzed were generally in accordance with the Cameroonian and Codex Alimentarius standard. This study suggests that vegetable oils sampled in the Cameroonian market may not expose consumers to lipid oxidation products generating pathological oxidative stress and inflammation. However, efforts in application of existing standard need to be done as far as labeling are concerned. 展开更多
关键词 vegetable Oils Quality Control Labeling Compliance Lipid Oxidation Oxidative Pathology
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Impact of climate and human activity on NDVI of various vegetation types in the Three-River Source Region, China
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作者 LU Qing KANG Haili +2 位作者 ZHANG Fuqing XIA Yuanping YAN Bing 《Journal of Arid Land》 SCIE CSCD 2024年第8期1080-1097,共18页
The Three-River Source Region(TRSR)in China holds a vital position and exhibits an irreplaceable strategic importance in ecological preservation at the national level.On the basis of an in-depth study of the vegetatio... The Three-River Source Region(TRSR)in China holds a vital position and exhibits an irreplaceable strategic importance in ecological preservation at the national level.On the basis of an in-depth study of the vegetation evolution in the TRSR from 2000 to 2022,we conducted a detailed analysis of the feedback mechanism of vegetation growth to climate change and human activity for different vegetation types.During the growing season,the spatiotemporal variations of normalized difference vegetation index(NDVI)for different vegetation types in the TRSR were analyzed using the Moderate Resolution Imaging Spectroradiometer(MODIS)-NDVI data and meteorological data from 2000 to 2022.In addition,the response characteristics of vegetation to temperature,precipitation,and human activity were assessed using trend analysis,partial correlation analysis,and residual analysis.Results indicated that,after in-depth research,from 2000 to 2022,the TRSR's average NDVI during the growing season was 0.3482.The preliminary ranking of the average NDVI for different vegetation types was as follows:shrubland(0.5762)>forest(0.5443)>meadow(0.4219)>highland vegetation(0.2223)>steppe(0.2159).The NDVI during the growing season exhibited a fluctuating growth trend,with an average growth rate of 0.0018/10a(P<0.01).Notably,forests displayed a significant development trend throughout the growing season,possessing the fastest rate of change in NDVI(0.0028/10a).Moreover,the upward trends in NDVI for forests and steppes exhibited extensive spatial distributions,with significant increases accounting for 95.23%and 93.80%,respectively.The sensitivity to precipitation was significantly enhanced in other vegetation types other than highland vegetation.By contrast,steppes,meadows,and highland vegetation demonstrated relatively high vulnerability to temperature fluctuations.A further detailed analysis revealed that climate change had a significant positive impact on the TRSR from 2000 to 2022,particularly in its northwestern areas,accounting for 85.05%of the total area.Meanwhile,human activity played a notable positive role in the southwestern and southeastern areas of the TRSR,covering 62.65%of the total area.Therefore,climate change had a significantly higher impact on NDVI during the growing season in the TRSR than human activity. 展开更多
关键词 growing season normalized difference vegetation index(NDVI) highland vegetation trend analysis partial correlation analysis residual analysis contribution rate
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