Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2023-07-11
Abstract： [Purposes] Regional closure of academic journals is not conducive to the sustainable development of journals, and exploring the regional coverage of academic journals and the correlation characteristics of inter-regional paper publishing is conducive to the high-quality construction of academic journals and the positive interaction with academic output. [Methods] ① The distribution of academic journals in China was unbalanced, with a few provinces owning the vast majority of academic journals, showing a spatial negative correlation, with Shanxi and Hebei as local depressions and Guangdong as local highlands; There is a polycentric trend between the output of core papers and the publication, and the latter is more unbalanced. On the whole, Central China and Northeast China are more balanced, and the difference within North China is the largest. The regional imbalance of journals at the discipline level is particularly pronounced in medical journals and industrial journals. ② The correlation between the output of core papers and publication is concentrated in a few provinces, the clustering characteristics of the two "two-way spillover plates" are obvious, and the academic output capacity of the "broker plate" in provinces still needs to strengthen its own journal construction. ③ The internal attributes of journals and research input are the dominant factors affecting the development of regional academic journals. The development of academic journals in provinces with more academic output is relatively prosperous, but it is easy to appear regional tendency. There is a synergistic effect among the impact factors. The more researchers, economic support and cooperative institutions in the region, the more conducive to the formation of a good academic ecological environment, so as to promote academic exchanges and the high-quality construction of academic journals. [Conclusions] The regional imbalance in the development level of Chinese academic journals is more severe than that in academic output. Strengthening personnel training, increasing scientific research investment and appropriately increasing publication frequency are conducive to the development of regional academic journals and promoting academic interaction.
Subjects: Geosciences >> Hydrology submitted time 2023-02-02 Cooperative journals: 《干旱区地理》
Abstract：青藏高原受气候变化影响，干湿过渡状况不断扩大，凝结水是旱区重要的水分补给来源，研究凝结水对青藏高原生态具有重要意义。为探究凝结水在青藏高原的形成特征以及影响凝结水形成因素，选取近年来受气候影响较大的可可西里盐湖地区作为研究区，使用微型蒸渗仪探究其0~10 cm土壤水分蒸发凝结特征，并利用相关回归分析、主成分分析探究影响凝结水形成因素。结果表明：（1）在14:00次日14:00期间，气温和土层温度均呈现出先减小后增大的变化趋势，0~10cm土壤在00:0010:00内有明显土壤凝结水形成，而在其余时间水量蒸发明显。大气水汽和土壤深层水汽组成土壤凝结水的比例约为1:3。当夜间近地空气相对湿度大于64%，近地气温小于3.8 ℃，5 cm土层温度低于4.1 ℃，有利于土壤凝结水的形成，平均水量可达0.2 mmd-1。（2）相关分析表明土壤总凝结水量与5 cm土层温度和5~30 cm土层温度差呈显著负相关，而且凝结水量与相关因子的线性拟合效果较好；大气水汽凝结水量与气温呈现显著负相关，与相对湿度呈现显著正 相关。主成分分析结果显示0~10 cm以上土层微气象因子对凝结水形成因素较大。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-09 Cooperative journals: 《干旱区研究》
Abstract：通过对柴达木盆地124个样点的表土孢粉分析和植被样方调查，研究了盆地表土孢粉与植被的对应关系。结果表明：柴达木盆地的表土孢粉组合能较好地反应当地植被特征，但是在具体的科属组成上有差异。藜科、蒿属、麻黄属等花粉R值大于1，具有超代表性；柽柳属、菊科等花粉R值小于1，具有低代表性，但对植被具有一定指示意义；禾本科和白刺属花粉在大多数样点具有低代表性，但禾本科花粉在建群种样点、白刺属花粉在盐碱区都具有适中代表性。主要科属花粉百分比与植被盖度之间具有一定相关性，禾本科、莎草科、菊科、柽柳属的相关性较高，可以建立相应函数关系。盆地西部的无植被区仍有相当含量的花粉，主要为藜科、蒿属、麻黄属、松属等超代表性花粉。盆地蒿属与藜科花粉比值（A/C）呈东南-西北递减趋势，与盆地由东南-西北逐渐干旱的环境特点很好对应。主要草灌木表土花粉数据的主成分分析表明，该区花粉组合主要受水文和土壤盐碱度等因素控制。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-11 Cooperative journals: 《干旱区地理》
Abstract：新疆夏尔希里自然保护区保持着较为原始的生态环境，是研究植被与环境变化的理想区域。通过在保护区内从海拔1 042~2 426 m的山地草原化荒漠带、山地干草原带和山地森林带采集的33个表土孢粉样品，结合对每个样点做的植被样方调查，根据孢粉数据进行有序聚类分析和冗余分析，探讨了表土孢粉组合特征与植被之间的对应关系。结果表明：3个孢粉组合带的特征与各垂直带植被总体上有较好的对应；藜科和麻黄属花粉含量与样方植物盖度无明显相关性，这两类孢粉呈现超代表性分布特征，应该是随气流从低海拔地带传播到山地高海拔地带的区域外花粉；桦属花粉和豆科花粉与对应的桦木林及锦鸡儿灌丛植被群落有较好的对应；[WTBX]A/C[WTBZ]比值和孢粉总浓度大小在区分森林带与草原化荒漠植被带时有明显的指示意义；蕨类植物孢子与降水量和海拔高度正相关，豆科植物花粉与温度正相关。由于山地地形因素引起的土壤、水分及光照度差异，在相同海拔高度的阳坡与阴坡形成的森林植被和中山草甸植被交替的过渡植被，因此孢粉组合中出现较多的花粉混合，进而降低了云杉和桦属花粉与植被盖度的相关性，这类木本花粉与植被之间的数量关系较为复杂。该现象在植物生态学分析中具有普遍性，但对表土孢粉数据在植被与气候定量重建中的应用具有较大的影响。在运用山地表土孢粉数据进行植被与气候定量重建时，需要结合植被样方资料和沉积环境特征对表土孢粉数据进行校正和筛选。
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