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81.
分析了城市特色的内涵;系统梳理了遵化市城市绿地系统特色要素构成,即人文要素和自然要素;指出遵化市城市绿地系统特色应通过以下6点来塑造,即顺应良好的城市地理环境条件,与城市布局结构形成共轭关系,布局上尊重城市自然肌理,城市蓝脉水系的营构,尊重地方文化,延续城市文脉,塑造城市绿脉特色。 相似文献
82.
83.
Importance of Wetland Landscape Structure to Shorebirds Wintering in an Agricultural Valley 总被引:2,自引:1,他引:2
Only recently has the influence of landscape structure on habitat use been a research focus in wetland systems. During non-breeding
periods when food can be locally limited, wetland spatial pattern across a landscape may be of great importance in determining
wetland use. We studied the influence of landscape structure on abundances of wintering Dunlin (Calidris alpina) and Killdeer (Charadrius vociferus) observed on wetlands in the agricultural Willamette Valley of Oregon, USA, during two winters (1999–2000, 2000–2001) of
differing rainfall. We examined (1) shorebird use within a sample of 100 km2 regions differing in landscape structure (hectares of shorebird habitat [wet, unvegetated]) and (2) use of sites differing
in landscape context (area of shorebird habitat within a species-defined radius). For use of sites, we also assessed the influence
of two local characteristics: percent of soil exposed and area of wet habitat. We analyzed data using linear regression and
information-theoretic modeling. During the dry winter (2000–2001), Dunlin were attracted to regions with more wetland habitat
and their abundances at sites increased with greater area of shorebird habitat within both the site and the surrounding landscape.
In contrast, Dunlin abundances at sites were related to availability of habitat at only a local scale during the wet winter
(1999–2000). Regional habitat availability was of little importance in predicting Killdeer distributions, and Killdeer site
use appeared unrelated to habitat distributions at both landscape and local scales. Results suggest prioritizing sites for
conservation that are located in areas with high wetland coverage. 相似文献
84.
冯昱 《信阳农业高等专科学校学报》2006,16(2):125-126
语用学从根本上讲是对语言在一定语境中所体现出来的具体意义的科学。本文就翻译的本质和语境的关系及如何在翻译中结合语境避免误译、死译,从而达到有效交际的目的予以分析。 相似文献
85.
黄敏 《湖南农业大学学报(自然科学版)》2001,(2)
在英汉翻译中 ,一个词应如何理解和翻译 ,取决于它特定的语境。语境包括微观语境和宏观语境。微观语境和宏观语境对英汉翻译中词义的确定都产生了重大影响 相似文献
86.
构建高等师范院校非计算机专业《计算机辅助教学》课程内容体系,论述课件设计工具的选取以及该课程应突出讲解的内容,旨在使非计算机专业学生经过有限的学习和实践,具备一定的课件设计能力。 相似文献
87.
提出一种基于条件随机场模型的梨园场景分割方法,条件随机场模型直接对分割目标的后验概率建模,融入图像空间上下文信息,使得条件随机场模型可以获得更精确的分割结果。将已标记的场景图像划分为超像素,超像素的特征向量和标记的类别作为学习样本整合到类别数据库中;将未标记场景图像划分为超像素,利用条件随机场和类别数据库对未标记图像超像素的特征向量和空间关系进行建模;训练获得模型参数,利用最大后验边缘准则对未标记超像素进行类别推理。实验结果表明,与改进的K-最近邻方法相比该算法可以更加准确地进行梨园场景分割。 相似文献
88.
章彩云 《信阳农业高等专科学校学报》2005,15(1):94-96
语言是文化的载体,同时又是文化的重要组成部分。文化背景的差异必然导致词汇文化内涵的不同。在跨文化交际及语言习得中,对词汇文化意义的理解有助于掌握所学语言。 相似文献
89.
采用实地调查和遥感数据分析相结合的方式,分析黄土高原北部神木县的土地沙化变化趋势及社会背景因素,为草地沙化的有效遏制提供依据。结果表明,神木县的土地沙化呈“整体缩小局部扩展”趋势。1986-2004年,沙化土地面积减少了10%(750 km2)。土地沙化在地区间有很大差异,县西北部乡镇里沙化土地减少明显,而南部的黄土峁地区沙化土地有所增加。与社会统计资料对比分析后发现,耕地面积比例大、人均土地面积少的乡镇地区,土地沙化趋势明显。以上结果意味着农田利用对黄土峁地区土地沙化有很大影响,传统耕作方式的改变有助于遏制土地沙化。 相似文献
90.
Determining the ecologically relevant spatial scales for predicting species occurrences is an important concept when determining species-environment relationships. Therefore species distribution modelling should consider all ecologically relevant spatial scales. While several recent studies have addressed this problem in artificially fragmented landscapes, few studies have researched relevant ecological scales for organisms that also live in naturally fragmented landscapes. This situation is exemplified by the Australian rock-wallabies’ preference for rugged terrain and we addressed the issue of scale using the threatened brush-tailed rock-wallaby (Petrogale penicillata) in eastern Australia. We surveyed for brush-tailed rock-wallabies at 200 sites in southeast Queensland, collecting potentially influential site level and landscape level variables. We applied classification trees at either scale to capture a hierarchy of relationships between the explanatory variables and brush-tailed rock-wallaby presence/absence. Habitat complexity at the site level and geology at the landscape level were the best predictors of where we observed brush-tailed rock-wallabies. Our study showed that the distribution of the species is affected by both site scale and landscape scale factors, reinforcing the need for a multi-scale approach to understanding the relationship between a species and its environment. We demonstrate that careful design of data collection, using coarse scale spatial datasets and finer scale field data, can provide useful information for identifying the ecologically relevant scales for studying species-environment relationships. Our study highlights the need to determine patterns of environmental influence at multiple scales to conserve specialist species such as the brush-tailed rock-wallaby in naturally fragmented landscapes. 相似文献