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Post-fire habitat restoration of sables during winter season in northern slope of the Great Xing'an Mountains 被引量:2
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作者 XIE Fu-ju LI Xiu-zhen +1 位作者 XIAO Du-ning Hong S. He 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期231-237,共7页
Habitat loss and fragmentation have been associated with the decline of endangered species. In 1987, a catastrophic fire in the northern Great Hing'an Mountains of China, where the main habitat of sables (Martes zib... Habitat loss and fragmentation have been associated with the decline of endangered species. In 1987, a catastrophic fire in the northern Great Hing'an Mountains of China, where the main habitat of sables (Martes zibellina) is located, aggravated the loss and fragmentation of the forest landscape. Due to restricted distribution and low population density, sables were listed in the national first-grade protected species in China. The objective of this paper was to identify to what extent the habitat of sables had been restored 13 years after the fire. Based on the behavioral data, which came from field survey information by radio-tracking, GPS (Global Positioning System) and forest inventory data, suitability habitat maps were derived using the Ecological Niche Suitability Model (ENSM). In addition, the habitat structure was analyzed with selected landscape indices. Although forest cover mostly had been restored by 2000, the results indicated that, compared to the pre-fire situation, the areas of suitable habitat had been reduced significantly, especially those of less suitable, marginally suitable and moderately suitable designation. Fragmentation was aggravated, and suitable patches were found to be further isolated with the exception of those in most suitable areas. The ratio of the patch perimeter to area in unsuitable, moderately suitable and suitable areas decreased, while the ratios within other suitability types increased. Moreover, the percentage of soft boundaries decreased slightly, which can influence the redistribution of sables. The results above indicated that the suitable habitat had deteriorated, and the restoration of the sables' habitat remained to be done. 展开更多
关键词 suitable habitat Habitat loss FRAGMENTATION Edge effect Habitat restoration.
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Suitable region of dynamic optimal interpolation for efficiently altimetry sea surface height mapping
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作者 Jiasheng Shi Taoyong Jin 《Geodesy and Geodynamics》 EI CSCD 2024年第2期142-149,共8页
The dynamic optimal interpolation(DOI)method is a technique based on quasi-geostrophic dynamics for merging multi-satellite altimeter along-track observations to generate gridded absolute dynamic topography(ADT).Compa... The dynamic optimal interpolation(DOI)method is a technique based on quasi-geostrophic dynamics for merging multi-satellite altimeter along-track observations to generate gridded absolute dynamic topography(ADT).Compared with the linear optimal interpolation(LOI)method,the DOI method can improve the accuracy of gridded ADT locally but with low computational efficiency.Consequently,considering both computational efficiency and accuracy,the DOI method is more suitable to be used only for regional applications.In this study,we propose to evaluate the suitable region for applying the DOI method based on the correlation between the absolute value of the Jacobian operator of the geostrophic stream function and the improvement achieved by the DOI method.After verifying the LOI and DOI methods,the suitable region was investigated in three typical areas:the Gulf Stream(25°N-50°N,55°W-80°W),the Japanese Kuroshio(25°N-45°N,135°E-155°E),and the South China Sea(5°N-25°N,100°E-125°E).We propose to use the DOI method only in regions outside the equatorial region and where the absolute value of the Jacobian operator of the geostrophic stream function is higher than1×10^(-11). 展开更多
关键词 Dynamic optimal interpolation Linearoptimal interpolation Satellite altimetry Sea surface height suitable region
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Potentially Suitable Area and Change Trends of Tulipa iliensis under Climate Change
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作者 Douwen Qin Weiqiang Liu +1 位作者 Jiting Tian Xiuting Ju 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期981-1005,共25页
Tulipa iliensis,as a wild plant resource,possesses high ornamental value and can provide abundant parental materials for tulip breeding.The objective of this research was to forecast the worldwide geographical spread ... Tulipa iliensis,as a wild plant resource,possesses high ornamental value and can provide abundant parental materials for tulip breeding.The objective of this research was to forecast the worldwide geographical spread of Tulipa iliensis by considering bioclimatic,soil,and topographic variables,the findings of this research can act as a benchmark for the conservation,management,and utilization of Tulipa iliensis as a wild plant resource.Research results indicate that all 12 models have an area under curve(AUC)of the receiver operating characteristic curve(ROC)values greater than 0.968 for the paleoclimatic,current,and future climate scenarios,this suggests an exceptionally high level of predictive accuracy for the models.The distribution of Tulipa iliensis is influenced by several key factors.These factors include the mean temperature of the driest quarter(Bio9),calcium carbonate content(T_CACO3),slope,precipitation of the driest month(Bio14),Basic saturation(T_BS),and precipitation of the coldest quarter(Bio19).During the three paleoclimate climate scenarios,the appropriate habitats for Tulipa iliensis showed a pattern of expansion-contraction expansion.Furthermore,the total suitable area accounted for 13.38%,12.28%,and 13.28%of the mainland area,respectively.According to the current climate scenario,the High-suitability area covers 61.78472×10^(4)km^(2),which accounts for 6.57%of the total suitable area,The Midsuitability area covers 190.0938×10^(4)km^(2),accounting for 20.2%of the total suitable area,this represents a decrease of 63.53%~67.13%compared to the suitable area of Tulipa iliensis under the paleoclimate scenario.Under the Shared Socioeconomic Pathways(SSP)scenarios,in 2050 and 2090,Tulipa iliensis is projected to experience a decrease in the High,Mid,and Low-suitability areas under the SSP126 climate scenario by 7.10%~12.96%,2.96%~4.27%and 4.80%~7.96%,respectively.According to the SSP245 scenario,the high suitability area experienced a slight expansion of 2.26%in 2050,but a reduction of 6.32%in 2090.In the SSP370 scenario,the High-suitability areas had a larger reduction rate of 11.24%in 2050,while the Mid-suitability and Low-suitability areas had smaller expansion rates of 0.36%and 4.86%,respectively.In 2090,the High-suitability area decreased by 4.84%,while the Mid and Low-suitability areas experienced significant expansions of 15.73%and 45.89%,respectively.According to the SSP585 scenario,in the future,the High,Mid,and Low-suitability areas are projected to increase by 5.09%~7.21%,7.57%~17.66%,and 12.30%~48.98%,respectively.The research offers enhanced theoretical direction for preserving Tulipa iliensis’genetic variety amidst evolving climatic scenarios. 展开更多
关键词 Tulipa iliensis MaxEnt model climate change distribution of suitable habitats
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Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China
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作者 YANG Ao TU Wenqin +9 位作者 YIN Benfeng ZHANG Shujun ZHANG Xinyu ZHANG Qing HUANG Yunjie HAN Zhili YANG Ziyue ZHOU Xiaobing ZHUANG Weiwei ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2024年第10期1380-1408,共29页
In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of... In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China. 展开更多
关键词 HALOPHYTES climate change global warming maximum entropy(MaxEnt)model soil salinization suitable habitats Northwest China
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Development of a Suitable,Cultural,and Life-Oriented Kindergarten Curriculum
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作者 Yuxuan Sun 《Journal of Contemporary Educational Research》 2024年第1期88-95,共8页
The technological revolution and the explosion of information have created a diverse world.More and more so-called advanced cultures are entering kindergartens,prompting us to think about how to correctly develop the ... The technological revolution and the explosion of information have created a diverse world.More and more so-called advanced cultures are entering kindergartens,prompting us to think about how to correctly develop the existing local cultures in the cultural context,while simultaneously accepting and absorbing the appropriate parts of foreign cultures.It is also necessary to maintain a balance between diversity and localization to prevent kindergartens from becoming a“colony”of foreign cultures.The development of suitable,cultural,and life-oriented kindergarten curricula from different perspectives is the focus of such a balance.Only in this way can kindergartens truly fulfill their educational functions and provide a vibrant and colorful environment for children. 展开更多
关键词 Kindergarten curriculum SUITABILITY CULTURE Life-oriented
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Index Identification of Suitable Temperature at the Booting Stage and Accumulated Temperature over 10℃ during the Whole Growth Period in Rice in the South of China 被引量:5
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作者 谢佰承 罗伯良 +2 位作者 殷剑敏 宋忠华 李迎春 《Agricultural Science & Technology》 CAS 2008年第4期64-67,共4页
According to phenological observation data of fourteen stations in Hunan,Hubei and Jiangxi provinces from 1994 to 2006,indices of suitable temperature at the booting stage and accumulated temperature(≥10 ℃)during th... According to phenological observation data of fourteen stations in Hunan,Hubei and Jiangxi provinces from 1994 to 2006,indices of suitable temperature at the booting stage and accumulated temperature(≥10 ℃)during the whole growth period in early or late rice in the south of China were analyzed by statistics and biological relationship between factors.Indices of the optimum daily mean temperature and the minimum temperature at the booting stage were as follows:Early convention rice variety was 25.7 ℃ and 22.3 ℃ respectively,hybrid variety was 26.5 ℃ and 23.3℃ respectively;while late convention rice variety was 25.6 ℃ and 22.3 ℃ respectively,hybrid variety was 25.8 ℃ and 22.6 ℃ respectively.Indexes of accumulated temperature during the whole growth period were as follows:The early-maturing variety,the middle-maturing variety and the late-maturing variety of early rice was 2 512.1 ℃,2 528.4 ℃ and 2 651.3 ℃ respectively,while the early-maturing variety,the middle-maturing variety and the late-maturing variety of late rice was 3 126.2 ℃,3 031.5 ℃ and 3 335.2 ℃ respectively.The above indexes all met the requirements of identification,which could provide reference for formulating the meteorological standard of rice in the south of China. 展开更多
关键词 RICE Booting STAGE suitable TEMPERATURE Accumulated TEMPERATURE IDENTIFICATION
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Ecological Regionalization of Suitable Trees, Shrubs and Herbages for Vegetation Restoration in the Farming-Pastoral Zone of Northern China 被引量:5
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作者 康慕谊 董世魁 +3 位作者 黄晓霞 熊敏 陈海 张新时 《Acta Botanica Sinica》 CSCD 2003年第10期1157-1165,共9页
To provide materials for the selection of plant species for vegetation restoration and reconstruction in the farming-pastoral zone in northern China, where the eco-environment has been already deteriorated by over-far... To provide materials for the selection of plant species for vegetation restoration and reconstruction in the farming-pastoral zone in northern China, where the eco-environment has been already deteriorated by over-farming and over-grazing, the suitable trees, shrubs and herbages were examined, screened and identified under the guidance of four principles of taking precedence for ecological conservation, being beneficial to economic production, matching species (trees, shrubs and herbages) with the site, and giving consideration to the integrity of local administrative division. According to the key ecological factors that determine species growth and distribution in the zone, i.e., the lowest daily mean temperature in a year, annual accumulated temperature, and water regimes represented by the moist index, the ratio between annual rainfall and accumulated temperature (>0 degreesC), as well as the soil type influenced by climate, surface substances and landform, the farming-pastoral zone was regionalized into seven parts: ( I) Western Songliao Plain and Da Hinggan Mountain Region; (II) Upper Liaohe River Sandy Region; (III) Mid-Eastern Nei Mongol Plateau and Northwestern Heibei Mountain Region; (IV) Luliang, Taihang and Yanshan Mountain Region; ( V) Ordos Plateau Sandy Region; (VI) Northern Shaanxi to Eastern Gansu Loess Plateau Region; and (VII) Mid Gansu to Eastern Qinghai Plateau Loess Region. And the suitable trees, shrubs and herbages for each region were selected and tabularly introduced in detail. 展开更多
关键词 farming-pastoral zone ecological regionalization suitable species for vegetation restoration northern China
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重庆缙云山国家级自然保护区边缘区土地利用冲突评估研究
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作者 彭琳 陈烨 《园林》 2025年第1期33-43,共11页
随着全球城市化地区的快速扩张,城市化压力下自然保护地的持久性和保护成效问题备受国内外关注。在权衡自然保护和城市社会经济发展的过程中,城市自然保护地边缘区土地利用冲突问题成为保护利用协调管理的难点及保护成效的关键影响因子... 随着全球城市化地区的快速扩张,城市化压力下自然保护地的持久性和保护成效问题备受国内外关注。在权衡自然保护和城市社会经济发展的过程中,城市自然保护地边缘区土地利用冲突问题成为保护利用协调管理的难点及保护成效的关键影响因子,亟需科学的土地冲突评估方法作为精准介入的技术支撑。构建由制度性冲突、保护利用冲突、不同利用方式冲突三类构成的城市自然保护地边缘区土地利用冲突分类和评估框架,采用矩阵分析法、MaxEnt生境模拟法、土地多宜性分析法等方法,以位于重庆主城的缙云山国家级自然保护区为案例地进行实证运用。识别结果表明,从冲突规模来看,不同利用方式冲突易发区的面积最大,制度性冲突易发区的面积最小;从冲突类型来看,不同利用方式冲突与保护利用冲突的分布重叠度较高;从冲突强度来看,高强度的土地利用冲突大部分位于城镇化程度较高的区域。从空间规划和冲突治理两个方面,提出了缙云山国家级自然保护区边缘区的规划调控建议,为城市自然保护地边缘区的规划管理政策制定提供支撑。 展开更多
关键词 城市自然保护地 土地利用冲突 边缘区 土地多宜性分析法 MaxEnt生境模拟法 缙云山国家级自然保护区
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泰顺县中华穿山甲栖息地适宜性评价
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作者 刘雷雷 余盛武 +2 位作者 王诗丰 章书声 程宏毅 《浙江师范大学学报(自然科学版)》 CAS 2025年第1期60-67,共8页
通过构建中华穿山甲在泰顺县的潜在分布预测模型,评估模型的预测精度,识别影响中华穿山甲分布的关键环境因子,预测泰顺县内中华穿山甲的潜在适宜分布区域.采用最大熵模型(MaxEnt)构建中华穿山甲的潜在分布预测模型,利用AUC值评估模型的... 通过构建中华穿山甲在泰顺县的潜在分布预测模型,评估模型的预测精度,识别影响中华穿山甲分布的关键环境因子,预测泰顺县内中华穿山甲的潜在适宜分布区域.采用最大熵模型(MaxEnt)构建中华穿山甲的潜在分布预测模型,利用AUC值评估模型的预测精度以分析环境变量的贡献率和重要性排序,并识别关键影响因子;基于响应曲线分析中华穿山甲的生境偏好,根据MaxEnt模型的预测结果,确定泰顺县内的潜在适宜分布区域.结果表明:训练集AUC值为0.838,模型预测结果达到“好”的标准,可信度较高,坡度、距道路距离和距居民点距离是影响中华穿山甲分布的前三大关键因子,累计贡献率高达84.8%;中华穿山甲最适宜的生境条件为:海拔低于600 m、距离居民点和道路超过100 m、距离水源100~800 m、坡度大于30°、南坡及西南坡方向;泰顺县内中华穿山甲的高中适宜分布区总面积约为459.5 km^(2),占县域面积的28.5%;中华穿山甲偏好相对封闭、远离人类干扰活动的生境,具体为较低海拔、地形平缓、不受人为干扰的常绿阔叶林或针阔混交林.研究为中华穿山甲的保护管理提供了科学依据,如优先保护高中适宜区域、限制人类活动干扰等,未来可进一步开展穿山甲种群动态监测,了解其实际分布状况,并采取针对性的保护措施. 展开更多
关键词 适宜栖息地 MaxEnt模型 中华穿山甲 环境因子 贡献率
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安徽省10-12月积温时空变化特征及冬小麦适宜播期分析
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作者 邓骋 赵莉 +6 位作者 杨太明 陈金华 包琪 白群升 何贤芳 林勇翔 汪建来 《麦类作物学报》 CAS 北大核心 2025年第1期73-79,共7页
为确定安徽省冬小麦适宜播期,利用1971-2021年安徽省分布于淮北、江淮及沿江麦区的50个气象站点观测数据,分析了10-12月积温时空变化特征,并基于叶龄积温法分析了前30 a(1971-2000年)与后21 a(2001-2021年)各地冬小麦冬前生长至不同叶... 为确定安徽省冬小麦适宜播期,利用1971-2021年安徽省分布于淮北、江淮及沿江麦区的50个气象站点观测数据,分析了10-12月积温时空变化特征,并基于叶龄积温法分析了前30 a(1971-2000年)与后21 a(2001-2021年)各地冬小麦冬前生长至不同叶龄对应的播期。结果表明,1971-2021年,安徽省及其各麦区10-12月每月积温及总积温均呈显著或极显著线性增加趋势,安徽省10-12月每月积温及总积温上升速率分别为8.6、9.6、7.8和26.1℃·(10 a)^(-1),安徽省及其各麦区10-12月每月积温上升速率呈现出11月>10月>12月规律;沿江麦区12月积温上升速率[6.5℃·(10 a)^(-1)]明显低于淮北[8.4℃·(10 a)^(-1)]及江淮[8.3℃·(10 a)^(-1)]麦区;淮北和江淮麦区10-12月总积温上升速率均为26.6℃·(10 a)^(-1),沿江麦区略低[24.9℃·(10 a)^(-1)]。安徽冬小麦冬前生长至相同叶龄时,后21 a播期比前30 a总体推迟1~4 d。淮北、江淮和沿江麦区后21 a适宜播期比前30 a分别平均推迟2.61、2.86和2.07 d。后21 a淮北麦区半冬性、弱冬性品种适宜播期分别为10月16-21日、10月12-16日,江淮麦区春性、半冬性品种适宜播期分别为10月25-30日、10月21-25日,沿江麦区春性品种适宜播期为10月30日-11月4日。 展开更多
关键词 安徽省 冬小麦 冬前积温 时空变化 适宜播期
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一种基于RSSI的智能家居环境Evil-Twin攻击的检测方法 被引量:4
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作者 房鼎益 祁生德 +2 位作者 汤战勇 陈晓江 顾元祥 《计算机学报》 EI CSCD 北大核心 2017年第8期1764-1778,共15页
Wi-Fi正在为各种各样的设备提供网络连接,但因其网络标识(SSID,BSSID)易被伪造,攻击者很容易伪造出普通用户无法识别的Evil-Twin AP并进行其他高级攻击.本文利用智能家居中AP位置稳定的特点,提出了基于RSSI的Evil-Twin攻击检测方法,它... Wi-Fi正在为各种各样的设备提供网络连接,但因其网络标识(SSID,BSSID)易被伪造,攻击者很容易伪造出普通用户无法识别的Evil-Twin AP并进行其他高级攻击.本文利用智能家居中AP位置稳定的特点,提出了基于RSSI的Evil-Twin攻击检测方法,它由单位置检测和多位置协同检测两种方案组成.该方法将Evil-Twin攻击检测问题转化为AP位置检测问题,两种方案都需要先在安全环境中构建指纹库.单位置检测时,确定当前检测到的目标AP与检测器之间的距离,并与指纹库中的安全距离进行比较,判断其安全性;多位置协同检测时,则先通过参考AP进行室内定位,确定检测设备的位置,然后反向定位确定当前检测到的目标AP与检测设备之间的距离,并与指纹库中该位置处的安全距离进行比较,判断其安全性.成功解决了基于AP硬件特征或流量特征的检测方法易被绕过的问题.该方法与已有的检测方法相比,检测设备不连入网络时依然可以成功检测,且无需加入专业的检测设备.实验结果显示,单位置检测方案将延迟时间降低至20s,且检测正确率达到98%,使用多位置协同检测时,正确率也达到90%. 展开更多
关键词 智能家居 邪恶双胞胎 无线网络 攻击位置检测 伪造AP 信号强度 物联网 传感器网络 信息物理融合系统
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伍大华从瘀论治三叉神经痛经验撷要
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作者 钟东 伍大华 +1 位作者 谢瑶 李映辰 《亚太传统医药》 2025年第1期103-106,共4页
三叉神经痛(TN)是一种常见的神经性疼痛疾病,临床上以内科药物或手术治疗为主要治疗手段,治疗效果存在个体差异,且有一定复发率,中医药治疗TN疗效较佳。伍大华教授认为,尽管三叉神经痛病因繁杂,但与瘀邪关系密切,瘀邪是TN发生、发展、... 三叉神经痛(TN)是一种常见的神经性疼痛疾病,临床上以内科药物或手术治疗为主要治疗手段,治疗效果存在个体差异,且有一定复发率,中医药治疗TN疗效较佳。伍大华教授认为,尽管三叉神经痛病因繁杂,但与瘀邪关系密切,瘀邪是TN发生、发展、预后及转归的基本病机,病理因素多围绕气瘀、血瘀、痰瘀、火瘀展开,从而提出了从瘀论治该病的观点,临证多以行气散瘀、活血逐瘀、化痰祛瘀、清热消瘀为基本治法,并以化瘀通络止痛为治疗原则,疗效颇显。 展开更多
关键词 三叉神经痛 名家经验 伍大华
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Suitable Region for Flue-cured Tobacco (Nicotiana glauca L.) Planting Based on Spatial Scene Similarity
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作者 董钧祥 郭旦怀 邵小东 《Agricultural Science & Technology》 CAS 2012年第9期1947-1949,1981,共4页
[Objective] The aim was to establish a model based on spatial scene similarity, for which soil, slope, transport, water conservancy, light, social economic factors in suitable planting areas were all considered. A new... [Objective] The aim was to establish a model based on spatial scene similarity, for which soil, slope, transport, water conservancy, light, social economic factors in suitable planting areas were all considered. A new suitable planting area of flue-cured tobacco was determined by comparison and analysis, with consideration of excellent area. [Method] Totaling thirty natural factors were chosen, which were clas- sified into nine categories, from Longpeng Town (LP) and Shaochong Town (SC) in Shiping County in Honghe Hani and Yi Autonomous Prefecture. [Result] According to weights, the factors from high to low were as follows: soil〉light〉elevation〉slope〉 water conservancy〉transport〉baking facility〉planting plans over the years〉others. The similarity of geographical conditions in the area was 0.894 3, which indicated that the planting conditions in the two regions are similar. If farmer population in unit area, farmland quantity for individual farmer, labors in every household, activity in planting flue-cured tobacco and work of local instructor were considered, the weights of different factors were as follows: farmer population in unit area〉farmland quantity for individual farmer〉farmers' activity in planting flue-cured tobacco〉educational back- ground〉labor force in every household〉instructor〉population of farmers' children at- tending school. The similarity of geographical conditions was 0.703 1, which indicated that it is none-natural factors that influence yield and quality of flue-cured tobacco. [Conclusion] According to analysis on suitable planting area of flue-cured tobacco based on assessment of spatial scene similarity, similarity of growing conditions in two spatial scenes can be analyzed and evaluated, which would promote further exploration on, influencing factors and effects on tobacco production. 展开更多
关键词 Similarity of spatial scene Planting of flue-cured tobacco suitable region
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The Struggle Between Good and Evil in Lord of the Flies
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作者 黄有新 《海外英语》 2010年第12X期208-208,210,共2页
In the west,a viewpoint of evil human nature is accepted by most of critics.William Golding exposes this hideous nature in Lord of the Flies.This paper analyses the ugly human performances in details,and it also see t... In the west,a viewpoint of evil human nature is accepted by most of critics.William Golding exposes this hideous nature in Lord of the Flies.This paper analyses the ugly human performances in details,and it also see the force about justice from the novel.The force is fighting with the evilness all the time.Although the justice is in a passive position temporarily,it finally defeats the evil. 展开更多
关键词 WILLIAM GOLDING evil HUMAN NATURE struggles
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Hawthorne's Short Stories:a Journey to Explore Evil
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作者 谢丽湘 《海外英语》 2011年第11X期262-263,共2页
Hawthorne was a great writer who reminds us of human limitations.He called his tales "allegories of the heart." Hawthorne's allegories are stories of how pride and isolation frustrate our capacity for lo... Hawthorne was a great writer who reminds us of human limitations.He called his tales "allegories of the heart." Hawthorne's allegories are stories of how pride and isolation frustrate our capacity for love and sympathy.Isolation or "alienation" is Hawthorne's principal theme and problem,and loss of contact with reality is the ultimate penalty he envisions.Therefore,reading Hawthorne's stories is a journey to explore human being's evil. 展开更多
关键词 HAWTHORNE evil DARK SYMBOL
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论我国当事人适格的判断——兼谈《民事诉讼法》第122条第1项的解释
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作者 陈国欣 《海南大学学报(人文社会科学版)》 2025年第1期207-216,共10页
我国《民事诉讼法》第122条第1项规定的“与本案有直接利害关系”本质上是实体当事人概念,这使得我国当事人适格的研究背景与德日颇为不同。从当事人适格的理论功能看,现有研究将第122条第1项解读为我国当事人适格标准是不妥当的;只有... 我国《民事诉讼法》第122条第1项规定的“与本案有直接利害关系”本质上是实体当事人概念,这使得我国当事人适格的研究背景与德日颇为不同。从当事人适格的理论功能看,现有研究将第122条第1项解读为我国当事人适格标准是不妥当的;只有对《民事诉讼法》第122条第1项进行低阶化解释,我国才有探讨当事人适格的理论空间。从文义和体系的角度解释《民事诉讼法》第122条第1项的“本案”和“利害关系”,可以有效降低我国的起诉条件,并创造出当事人适格探讨的理论空间。以比较法上当事人适格判断标准的四个学说为基础,结合我国现代型诉讼的处理模式,可分析并论证管理处分权说作为我国当事人适格判断标准的妥当性。 展开更多
关键词 当事人适格 正当当事人 利害关系 诉讼实施权 管理处分权
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应用优化最大熵模型的珍稀濒危玉兰属物种适生区预测
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作者 李秀玉 唐继敏 +2 位作者 殷晓洁 刘一飞 李子康 《东北林业大学学报》 CAS 北大核心 2025年第1期64-72,共9页
依据中国9种珍稀濒危玉兰属(Yulania spach)物种的地理分布数据及37个环境因子数据,利用R语言ENMeval包优化最大熵模型(MaxEnt)的正则化乘数(RM)和要素组合(FC)参数,提高模型模拟精度,以便更好的预测出各物种在基准期和未来3种气候情景... 依据中国9种珍稀濒危玉兰属(Yulania spach)物种的地理分布数据及37个环境因子数据,利用R语言ENMeval包优化最大熵模型(MaxEnt)的正则化乘数(RM)和要素组合(FC)参数,提高模型模拟精度,以便更好的预测出各物种在基准期和未来3种气候情景的潜在适生区分布趋势,并分析影响其分布的主要环境因子。结果表明:(1)最大熵模型优化后,各珍稀濒危玉兰属物种的受试者工作特征曲线(ROC)下面积(AUC)值均在0.95以上,表明模型模拟效果极好,可用于中国珍稀濒危玉兰属物种地理分布模拟;(2)影响珍稀濒危玉兰属潜在分布的主要环境因子,贡献率从大到小依次为,最冷月最低温(BIO6,46.38%)、等温性(BIO3,13.83%)、坡度(SLO,8.03%)、最暖季降水量(BIO18,7.57%)、最干月降水量(BIO14,6.78%),其中,对各物种潜在适生区分布影响最大的影响因子为最冷月最低温,在存在概率最高时,各物种的最冷月最低温均在0℃左右;(3)在未来2061—2080年3种不同的气候情景时,光叶玉兰、青皮玉兰、凹叶玉兰及紫玉兰总适生区面积呈扩大趋势,增加面积在7 398~879 439 km^(2);景宁玉兰、罗田玉兰、天目玉兰、宝华玉兰、滇藏玉兰总适生区面积呈缩减趋势,减小面积在1 605~669 830 km^(2)。 展开更多
关键词 气候变化 珍稀濒危树种 玉兰属 优化最大熵模型 适生区预测
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基于MaxEnt模型的冬樱花潜在引种区研究
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作者 贺鹭瑶 徐晓丹 郑伟 《园林》 2025年第1期134-139,共6页
冬樱花(Cerasus cerasoides)是全球唯一在冬季盛开的樱花,主要分布于中国云南省,园林应用潜力巨大,但近年来冬樱花向省外的引种并不成功。因此,研究冬樱花在中国的潜在适生区对冬樱花园林引种和推广应用具有重要意义。收集冬樱花275个... 冬樱花(Cerasus cerasoides)是全球唯一在冬季盛开的樱花,主要分布于中国云南省,园林应用潜力巨大,但近年来冬樱花向省外的引种并不成功。因此,研究冬樱花在中国的潜在适生区对冬樱花园林引种和推广应用具有重要意义。收集冬樱花275个地理分布信息、32个环境变量因子以及当代(1970–2000年)、未来(2021–2070年)的气候数据,利用最大熵模型(MaxEnt)和地理信息系统(ArcGIS),预测当代和未来气候环境下冬樱花在中国的潜在引种区,并通过基于刀切法的ROC曲线对预测精度进行检验。影响冬樱花潜在引种区分布的主要环境因子包括:季节性温度变化、最干月降水量、等温性和海拔。预测模型的评估指标(AUC值)为0.983,表明预测精度极高,结果可靠。当前气候条件下,冬樱花引种区总面积为4.99×10^(5)km^(2),占中国陆地面积5.42%。其中,高、中、低引种区面积分别为2.04×10^(5)km^(2)(2.21%)、1.23×10^(5)km^(2)(1.24%)、1.81×10^(5)km^(2)(1.96%)。冬樱花潜在引种区主要分布在西南地区及华南地区。未来气候条件下,冬樱花的潜在引种区总面积呈增加趋势,适生区以高适生区为中心向四周扩散,尤其是东南方向。旨在为冬樱花的引种栽培、推广应用和区划研究提供参考。 展开更多
关键词 高盆樱桃 生态位模型 引种 适宜区 预测
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Suitable growing zone and yield potential for late-maturity type of Yongyou japonica/indica hybrid rice in the lower reaches of Yangtze River, China 被引量:15
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作者 WEI Huan-he 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期50-62,共13页
Late-maturity type of Yongyou japonica/indica hybrids series (LMYS) have shown great yield potential, and are being widely planted in the lower reaches of Yangtze River, China. Knowledge about suitable growing zone ... Late-maturity type of Yongyou japonica/indica hybrids series (LMYS) have shown great yield potential, and are being widely planted in the lower reaches of Yangtze River, China. Knowledge about suitable growing zone and evaluation of yield advantage is of practicall importance for LMYS in this region. Fifteen LMYS, two high-yielding inbred japonica check varieties (CK-J) and two high-yielding hybrid indica check varieties (CK-I) were grown at Xinghua (119.57°E, 33.05°N) of Lixiahe region, Yangzhou (119.25°E, 32.30°N)of Yanjiang region, Changshu (120.46°E, 31.41°N)of Taihu Lake region, and Ningbo (121.31°E, 29.45°N) of Ningshao Plain in 2013 and 2014. The results showed that maturity dates of the 15 were later than the secure maturity date at Xinghua and 6, 14 and 15 LMYS were mature before the secure maturity date at Yangzhou, Changshu and Ningbo, respectively. One variety was identified as high-yielding variety among LMYS (HYYS) at Yangzhou, 8 HYYS in 201:3 and 9 HYYS in 2014 at Changshu, 9 HYYS at Ningbo. HYYS here referred to the variety among LMYS that was mature before the secure maturity date and had at least 8% higher grain yield than both CK-J and CK-I at each experimental site. Grain yield of HYYS at each experimental site was about 12.0 t ha-1 or higher, and was significantly higher than CK varieties. High yield of HYYS was mainly attributed to larger sink size due to more spikelets per panicle. Plant height of HYYS was about 140 cm, and was significantly higher than check varieties. Significant positive correlations were recorded between duration from heading to maturity stage and grain yield, and also between whole growth periods and grain yield. HYYS had obvious advantage over check varieties in biomass accumulation and leaf area duration from heading to maturity stage. Comprehensive consideration about safe matudty and yield performance of LMYS at each experimental site, Taihu Lake region (representative site Changshu) and Ningshao Plain (representative site Ningbo) were thought suitable growing zones for LMYS in the lower reaches of Yangtze River. The main factors underlying high yield ofHYYS were larger sink size, higher plant height, longer duration from heading to maturity stage and whole growth periods, and higher biomass accumulation and leaf area duration during grain filling stage. 展开更多
关键词 japonica/indica hybrid rice Yongyou series late-maturity type suitable growing zone yield potential
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Prediction of Suitable Habitat for Lycophytes and Ferns in Northeast China: A Case Study on Athyrium brevifrons 被引量:4
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作者 LI Yan CAO Wei +2 位作者 HE Xingyuan CHEN Wei XU Sheng 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1011-1023,共13页
Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery effort... Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery efforts.In this study, we took Athyrium brevifrons as an example, predicted its suitable habitat using a Maxent model with 67 occurrence data and nine environmental variables in Northeast China.The area under the curve(AUC) value of independent test data, as well as the comparison with specimen county areal distribution of A.brevifrons exhibited excellent predictive performance.The type of environmental variables showed that precipitation contributed the most to the distribution prediction, followed by temperature and topography.Percentage contribution and permutation importance both indicated that precipitation of driest quarter(Bio17) was the key factor in determining the natural distribution of A.brevifrons, the reason could be proved by the fern gametophyte biology.The analysis of high habitat suitability areas also showed the habitat preference of A.brevifrons: comparatively more precipitation and less fluctuation in the driest quarter.Changbai Mountains, covering almost all the high and medium habitat suitability areas, provide the best ecological conditions for the survival of A.brevifrons, and should be considered as priority areas for protection and restoration of the wild resource.The potential habitat suitability distribution map could provide a reference for the sustainable development and utilisation of A.brevifrons resource, and Maxent modelling could be valuable for conservation management planning for lycophytes and ferns in Northeast China. 展开更多
关键词 Athyrium brevifrons LYCOPHYTES and FERNS MAXENT suitable HABITAT NORTHEAST China GAMETOPHYTE
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