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海南岛成土母质的地形多样性分析 被引量:28
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作者 张学雷 陈杰 +2 位作者 张甘霖 檀满枝 Juan José Ibáez 《土壤学报》 CAS CSCD 北大核心 2004年第2期170-175,共6页
多样性指数、多度分布模型等统计手段长时间以来在生态学领域被用于分析不同生态体的发生规律。本研究中将类似手段用于地形多样性 (作为地多样性的研究案例 )分析中 ,讨论基于海南岛土壤—地形体数字化数据库 (SOTER) ,通过对不同成土... 多样性指数、多度分布模型等统计手段长时间以来在生态学领域被用于分析不同生态体的发生规律。本研究中将类似手段用于地形多样性 (作为地多样性的研究案例 )分析中 ,讨论基于海南岛土壤—地形体数字化数据库 (SOTER) ,通过对不同成土母质上地形类别的丰富度指数 (S)、多样性指数 (Shannon指数H′)和均匀度指数 (PielouE)的计算 ,不同成土母质上地形类别多度分布模型的建立与应用 。 展开更多
关键词 海南岛 成土母质 地形多样性 丰富度指数 多样性指数 均匀度指数 多度分布模型 地理信息系统
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考虑地形与生物多样性的InVEST模型及其在县域生物多样性安全格局分析中的应用 被引量:3
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作者 陈朝 杨贤房 +3 位作者 陈进栋 王琦 刘婷 邓南荣 《环境工程技术学报》 CAS CSCD 北大核心 2023年第4期1345-1353,共9页
县域尺度生物多样性安全格局精细评估可为区域生物多样性保护规划、实施与管理提供科学参考。以粤北山区翁源县为例,采用InVEST生境质量模型,结合区域地形与生物多样性特征,以生境质量指数、地形与生物多样性综合指数为评价指标,开展区... 县域尺度生物多样性安全格局精细评估可为区域生物多样性保护规划、实施与管理提供科学参考。以粤北山区翁源县为例,采用InVEST生境质量模型,结合区域地形与生物多样性特征,以生境质量指数、地形与生物多样性综合指数为评价指标,开展区域生物多样性安全格局综合评估。结果表明:翁源县整体生境质量指数(HQI)较高,尤其在人为扰动较弱的水系和林区最为明显,生境质量指数较低区集中在建设用地、耕地等人类活动影响强烈区域;地形多样性综合指数(TDCI)与地形起伏度和地形坡度位置指数分布格局较为一致,而与地形湿度指数相对差值分布格局相反;生物多样性指数(BCI)分布格局受到香农-威纳指数物种多样性本底及生物多样性丰富度、人类足迹指数、生物多样性重要度与植被总覆盖度的交互影响;生物多样性综合安全格局指数与HQI、BCI及TDCI分布有较好的一致性,低风险/低脆弱(高安全)区集中在县域内城镇建设用地、交通水利和耕地等人类活动强烈区,高风险/高脆弱(低安全)区主要分布在县域北部、西北部、东南部、东北部自然保护和饮用水源等人类活动干扰微弱区。通过与区域生态保护红线等相关资料进行验证与分析,改进优化后的评估结果更能精细和客观地反映研究区生物多样性安全格局。 展开更多
关键词 InVEST生境质量模型 生物多样性综合指数 地形多样性综合指数 生物多样性安全格局 翁源县
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地形及土壤多样性与耕地动态变化的相关分析 被引量:3
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作者 李笑莹 张学雷 任圆圆 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2019年第11期1755-1766,共12页
本文以河南豫北、豫中和豫南3个典型样区为研究对象,运用地统计学方法,从多样性、相关性角度定量分析了地形、土壤的多样性特征及其与耕地变化(2001年、2007年和2017年)面积的空间分布多样性特征的关系,以期为耕地资源动态变化的驱动力... 本文以河南豫北、豫中和豫南3个典型样区为研究对象,运用地统计学方法,从多样性、相关性角度定量分析了地形、土壤的多样性特征及其与耕地变化(2001年、2007年和2017年)面积的空间分布多样性特征的关系,以期为耕地资源动态变化的驱动力分析及合理利用提供新的研究角度。研究表明:1)豫北和豫中样区的地形构成组分多样性呈现出均匀性,豫南样区表现为相对单一性;各研究区的地形空间分布多样性为平原>丘陵>山地。2)豫南的土壤构成组分最为均匀且丰富,豫中的土壤构成组分相对单一;各研究区的典型土壤各异但总体上分布皆较均匀,各样区的土壤空间分布多样性的显著差异与地形条件密切相关。3)研究尺度影响地形、土壤空间分布多样性特征的表达, 3 km×3 km网格是相对适宜的研究尺度。4)地形和土壤的空间分布多样性指数与耕地变化面积空间分布都具有明显的相关性,其中地形中平原相关性较大,达0.95左右;各样区典型土壤如豫南的水稻土,豫中、豫北的褐土以及豫北的潮土的相关性更为明显,达0.9以上。综合来看,典型样区的地形、土壤因子的构成组分多样性及空间分布格局有显著差别;在不同网格尺度下,耕地的变化面积与地形、土壤因子的空间分布多样性指数密切相关。 展开更多
关键词 地形多样性 土壤多样性 耕地面积 空间分布 网格尺度
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Spatial distribution of mountainous regions and classifications of economic development in China 被引量:23
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作者 FANG Yi-ping YING Bin 《Journal of Mountain Science》 SCIE CSCD 2016年第6期1120-1138,共19页
China is a mountainous country with a great diversity of landform and geomorphology.This diversity underlines the need for regionalization and classification.This study defines the mountain terrains and regions with t... China is a mountainous country with a great diversity of landform and geomorphology.This diversity underlines the need for regionalization and classification.This study defines the mountain terrains and regions with three criteria-elevation,relative height,and slope,and examines the extent of mountainous regions by using county as the basic administrative unit.According to the three parameters of economic base,resident income and development potential,we classified the economic development level in mountainous regions of China.The findings reveal that the extent of the mountainous region accounts for 74.9% of the China's Mainland's total area.The economic development of mountainous regions in China is classified into 4 main types and 23 subtypes. 展开更多
关键词 Mountain terrain Mountainous region Classification system Economic development China
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Current Vegetation Pattern along Glacial Landscape in Central (Garhwal) Himalaya, India 被引量:1
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作者 Uday N. Gaur G.P. Raturi A.B. Bhatt 《Journal of Mountain Science》 SCIE CSCD 2005年第3期255-264,共10页
Current vegetation patterns, biodiversity and adaptation of plants were studied during 1998-2001 in glacial landscape of Chaurabari situated above Kedarnath (30° 44' N- 79° 07' E; 3,000- 6,000 m) in Cent... Current vegetation patterns, biodiversity and adaptation of plants were studied during 1998-2001 in glacial landscape of Chaurabari situated above Kedarnath (30° 44' N- 79° 07' E; 3,000- 6,000 m) in Central Himalaya. Landscape was identified into different zones on account of the vegetation status, glacial features, geomorphology and altitudes. Cold environment with heavy snowfall, frost hailstorm and dense frost characterizes the study area Predominance of the soda rich feldspars indicates soda enrichment; orthoclase, microcline weathering and alternation would have contributed potash to the soil. The increasing severity of the environment as we ascend from timberline to snowline leads to progressive decline in the abundance and diversity of the plant species. The diversity of the higher plants decrease, while the diversity of microflora increase from alpine zone to snowline zone. Highly opulent and diverse flora with beautiful, delicate herbs occupy the alpine zone, but some specialized groups of the plants, particularly high energetic and cold resistant species reside in glacial environment. Asteraceae, Rananculaceae, Primulaceae, Rosaceae, Apiaceae and Ericaceae are the pioneer angiospermic families, while Anaphalis triplinervis, A. royleana, Androsacce sarmentosa, Cotoneaster rotundifolius,Lonicera myrtillus, Cassiope fastigiata, Gaultheria trichophylla and Erigeron multiradiatus are the pioneer species, which have invaded in glacial environment. Through its nature, alpine glacial ecotone can be seen easily due to environmental and edaphic differences. 展开更多
关键词 Glacial ecosystem vegetation pattern plant diversity
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Preliminary Assessment of Genetic Diversity in Three Taro (Colocasia esculenta L, Schott) Landraces Using Agro-morphological and SSR DNA Characterisation
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作者 Tafadzwanashe Mabhaudhi Albert Thembinkosi Modi 《Journal of Agricultural Science and Technology(B)》 2013年第4期265-271,共7页
Taro (Colocasia esculenta L. Schott) is an important underutilised crop in South Africa, East Africa and Indonesia. Three taro landraces, namely, Dumbe Lomfula (wild), KwaNgwanase and Umbumbulu, were collected fro... Taro (Colocasia esculenta L. Schott) is an important underutilised crop in South Africa, East Africa and Indonesia. Three taro landraces, namely, Dumbe Lomfula (wild), KwaNgwanase and Umbumbulu, were collected from two locations in KwaZulu-Natal (KZN), South Africa, and planted at two locations, Pietermaritzburg (KZN) and Roodeplaat, Pretoria. Ago-morphological characterisation of vegetative and corm characteristics were done four months after planting and at harvest, respectively. Sampling for DNA fingerprinting using five SSR primers was done using leaf material four months after planting. Agro-morphological characterisation was useful in showing differences between the wild landrace and the two cultivated landraces, as well as identification of dasheen and eddoe types. SSR primer characterisation showed that despite significant morphological difference, the wild Dumbe Lomfula and Umbumbulu landraces were closely related but different from the KwaNgwanase landrace. Although landraces showed great morphological variation, this did not necessarily imply genetic variation. It is concluded that SSR primers are more useful for characterising taro landraces. 展开更多
关键词 Agro-morphology characterisation DNA LANDRACES SSR primers taro (Colocasia esculenta L. Schott) geneticdiversity.
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Seasonal Effect on Atmospheric Refractivity in Diverse Terrains
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作者 Y.O. Olasoji M.O. Kolawole 《Journal of Environmental Science and Engineering》 2011年第11期1537-1541,共5页
Air masses in the atmosphere have contrasting temperature, humidity and moisture, which influence radio signals traversing the atmosphere. The influence of the atmosphere on refractivity is strongly determined by its ... Air masses in the atmosphere have contrasting temperature, humidity and moisture, which influence radio signals traversing the atmosphere. The influence of the atmosphere on refractivity is strongly determined by its temporal and spatial variability. This paper uses meteorological measurements to investigate the impact of meteorological structures on diverse environments evident in Nigeria. The study hypothesises that refractivity measures could serve as indicators of diurnal radio wave degradation traversing the atmosphere. 展开更多
关键词 RADIOSONDE REFRACTIVITY radio signal hydrostatic component Longley-Rice model
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Manipulated microtopography alters plant community development in fragile farm-pastoral transition zone 被引量:1
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作者 Minxuan Gao Yining Wang +2 位作者 Yongning Ren Jinyan Zhan Tian Xie 《Journal of Plant Ecology》 SCIE CSCD 2024年第5期176-188,共13页
The ecosystems within agro-pastoral transition zones exhibit inherent fragility and heightened susceptibility to climate variability,exacerbated by profound degradation resulting from anthropogenic activities.Subseque... The ecosystems within agro-pastoral transition zones exhibit inherent fragility and heightened susceptibility to climate variability,exacerbated by profound degradation resulting from anthropogenic activities.Subsequent vegetation degradation in these areas precipitates severe soil erosion,presenting formidable challenges for ecological restoration efforts.The utilization of microtopographic structures to mitigate soil erosion and facilitate vegetation recovery stands as a prominent strategy for vegetation restoration within agro-pastoral transition zones.Despite the acknowledgment in current restoration practices that the efficacy of microtopography-based restoration is contingent upon slope,aspect and elevation,there remains a notable absence of precise observed information on this correlation.This study,conducted in the Bashang Grassland,a typical agro-pastoral transition zone in northern China,aims to fill the information gap concerning the correspondence between microtopographic structures and restoration outcomes.Our findings revealed that microtopography has a significant impact on vegetation characteristics,with outcomes varying by location.Shaded slopes displayed higher biomass and density compared with sunny slopes and valleys.While microtopography affected community structure,it did not substantially alter species richness,highlighting the critical role of location and pit construction in successful restoration endeavors.This study provides insights for the selection,design and assessment of microtopography-based restoration in vulnerable ecosystems. 展开更多
关键词 community structure microtopography-based restoration plant diversity plant restoration soil erosion
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