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青海省宗教发展历史悠久,宗教旅游资源丰富,宗教场所的空间分布特征对青海省区域旅游格局有重要影响.对青海省宗教场所旅游资源进行了统计,分别从空间分布模式、差异性、密度等方面采用最邻近指数、地理集中指数、洛伦茨曲线、核密度方法对其空间格局特征进行了定量分析,并利用空间回归分析法探讨了其分布与海拔、坡度、交通、水系等因素的关系.结果表明:青海省宗教场所旅游资源呈“东多西少”的集聚分布态势,空间差异显著,旅游资源集中在青海省11%地区;空间分布密度呈由东向西辐射(型)的分布趋势;空间回归分析结果显示,在地势平坦、
ZHULitao(朱利涛) +3 more
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Abstract Although significant biodiversity has been safeguarded by protected areas (PAs), biodiversity trends continue downward. Within the frameworks of the EU Biodiversity Strategy for 2030 and the new EU Restoration Regulation (2024), conserving critical biodiversity areas is essential.
George Kefalas +14 more
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ABSTRACT Previous research has established the relationships between motivation, anxiety, teachers’ support, and self‐regulated learning (SRL) in English‐as‐a‐foreign‐language (EFL) learning. Most of the studies, however, have taken a variable‐centered approach in addressing the variable correlations, while learners’ characteristics and variable links ...
Yuhong Jiao, Barry Bai, Jing Li
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为研究南疆典型田块土壤盐分空间异质性,基于电磁感应调查获取表观电导率并解译土壤盐分信息,分别以5 m和15 m间隔进行网格布点调查研究田块土壤盐分空间变异的尺度效应.研究表明,土壤表层盐分含量与表观电导率之间具有显著线性相关性(r2=0.870),基于电磁感应解译土壤盐分含量具有较高的精度;块金效应、分维数以及Moran'sI指数均表明,田块小尺度土壤盐分空间变异受随机因素影响较大,过大尺度往往忽略小尺度空间变异特征,套合结构半方差函数兼顾小尺度效应,能更好地反映空间变异详细情况 ...
李晓明, 杨劲松, 杨奇勇
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研究黄土高原侵蚀环境下林地开垦后坡面土壤养分空间分布状况,确立林地开垦后侵蚀驱动的坡地土壤养分空间变异特征。以黄土高原丘陵区子午岭林地和开垦28年的侵蚀坡面为研究对象,分析土壤主要性质和养分含量的变化情况,运用经典统计学和地统计法分析坡面土壤基本性质和养分空间分布规律。林地开垦后坡面土壤pH增加了0.24个单位,有机质、全氮、全磷和铵态氮、硝态氮、速效磷和速效钾分别降低了13.77,1.14,0.10 g/kg和6.05,1.63,4.99,58.44 mg/kg。林地的土壤有机质 ...
王昭 +6 more
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Learner‐Focused Strategy Instruction From the Teachers’ and the Learners’ Perspective
ABSTRACT Numerous large‐scale quantitative studies have been conducted to yield a macro‐level picture of the effectiveness of strategy instruction. However, little is understood about learners' actual processing of strategy instruction and interaction with the teachers delivering it.
Isobel Kai‐Hui Wang, Andrew D. Cohen
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湿地土壤养分是时空连续的变异体,不论尺度大小均具有高度的空间异质性.湿地土壤养分变量属于区域化变量,同时具有随机性和结构性,仅运用经典的Fister统计方法已经不能满足土壤空间异质性研究的需要.地统计学是近几十年发展起来的一门新的空间分析方法,其变异函数则适合于定量研究区域化变量空间结构变异特征,能够全面反映区域化变量的结构性.作者在前人的工作基础上意欲用地统计学的区域化变量理论和变异函数对湿地土壤养分的空间异质性进行定量研究,并对其研究方法进行了构想.#
白军红 余国营 张玉霞
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利用美国喷气动力实验室(JPL)提供的全球电离层总电子含量(TEC)网格数据分析2018年5月28日吉林松原MS5.7地震空间电磁异常情况。通过算法对比确定滑动四分位法的优势,并利用该方法计算此次地震从震前14天至震后6天的电离层TEC异常变化的时间序列,结合空间环境和ΔTEC异常二维空间分布情况进一步分析,结果显示:① 极区磁亚爆强烈时段越靠近北部电离层扰动越强烈;② 震前TEC观测值先增大后减小,震后又回升,电离层异常幅度随着震中距的减小而增大;③ 电离层在空间分布上 ...
Hua Nian +6 more
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Synthesizing Empirical Research on Learner Metacognition in Second Language Writing
ABSTRACT Despite considerable research interest in learner metacognition in second language (L2) writing, there is not yet a review that synthesizes the existing empirical findings and discusses their implications. To fill the void, this systematic review synthesized 39 empirical studies on learner metacognition in L2 writing and examined their salient
Chen Li, Icy Lee, Zhicheng Mao
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通过对沙坡头地区不同植被类型沙地土壤表层水分时空变化特征的研究表明,该区不同植被类型沙地土壤表层水分的分布均符合正态分布,降雨使表层土壤水分的空间变异性减小,空间自相关性减弱,分维数减小,空间自相关范围由干旱时的5m左右内变化扩大到几十米,土壤表层水分的空间依赖性增强;在土壤表层水分含量极低的情况下,土壤表层水分的空间变异性规律与土壤水分含量的变化规律一致;在土壤水分含量不是很低的情况下,其空间变异性与土壤表层水分含量变化趋势相反,流沙地、柠条地A、柠条地B、油蒿地 ...
潘颜霞 +3 more
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