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1. chinaXiv:202010.00057 [pdf]

注意过程中的行为振荡现象

章小丹; 张沥今; 丁玉珑; 曲折
Subjects: Psychology >> Cognitive Psychology

行为振荡是个体心理加工过程的周期性动态变化在行为上的表现。通过高时间分辨率的行为采样方法,行为振荡研究为探索视觉注意的时间动态结构提供了一个新的视角。各种不同的注意任务中都发现存在行为振荡现象。大量行为振荡证据表明,注意过程存在两种主要的节律成分:反映注意抑制的α节律(8~13 Hz)和反映注意转移的θ节律(4~8 Hz)。这些结果有助于揭示注意的时间动态结构,也为序列搜索理论和平行搜索理论之间的争论提供了新的分析思路。行为振荡的节律特征会受到一些潜在因素(如任务难度、线索有效性)的影响。行为振荡和神经振荡在某些任务中表现出相同的节律成分,提示两者涉及了相似的心理过程。后续研究应进一步关注各种不同的注意控制过程以及多模态交互任务,深入探索其行为振荡特点,以更好地揭示注意的动态加工过程。

submitted time 2020-10-23 Hits26Downloads11 Comment 0

2. chinaXiv:202010.00016 [pdf]

人们何以能够“舍生取义”?基于保护性价值观认知神经机制的解释

岳童; 黄希庭; 傅安国
Subjects: Psychology >> Personality Psychology

保护性价值观是一种拒绝与其他任何价值相互交易,尤其拒绝与经济价值进行交易的观念。近些年来的认知神经科学研究证据表明,人们之所以可以为了坚守保护性价值观,表现出“舍生取义”的行为(如对抗利益诱惑甚至放弃生命),一方面由于保护性价值观是以一种道义主义的绝对规则方式进行表征和建构的,这使得人们较少进行利弊权衡;另一方面,由于保护性价值观与自我和道德认同过程紧密相关,使得其被主观赋予了最高价值。未来研究中,需要在进一步明确保护性价值观神经作用机理基础上,关注其文化差异问题,并开展对保护性价值观的干预和正确引导的应用实践研究。

submitted time 2020-10-22 Hits44Downloads17 Comment 0

3. chinaXiv:202010.00015 [pdf]

音乐愉悦体验的神经机制

周璨; 周临舒; 蒋存梅
Subjects: Psychology >> Other Disciplines of Psychology

愉悦情绪体验是音乐活动中最普遍的心理现象。通过系统回顾相关的神经科学研究,认为音乐愉悦体验与大脑奖赏系统的活动有关,并涉及伏隔核与听觉皮层等其他脑区的交互。在这个过程中,多巴胺的传递与音乐愉悦体验存在因果联系。基于预期视角,奖赏预测误差和音乐信息理论模型可以解释音乐愉悦体验的产生机制。未来研究应进一步检验伏隔核及各皮层在音乐愉悦体验中的功能,并整合不同的预期理论。

submitted time 2020-10-22 Hits44Downloads19 Comment 0

4. chinaXiv:202010.00014 [pdf]

有中介的调节模型的拓展及其效应量

刘红云; 袁克海; 甘凯宇
Subjects: Psychology >> Statistics in Psychology

传统的有中介的调节(mediated moderation, meMO)模型关于误差方差齐性的假设经常被违背,应用研究中也缺乏测量meMO效应大小的指标。对于单层数据,本文借助于两层建模的思想,提出了一种可用于处理方差非齐性的两层有中介的调节(2meMO)模型;给出了用于测量meMO分析中总调节效应、直接调节效应和有中介调节效应大小的效应量。通过Monte Carlo模拟研究,比较了meMO和2meMO模型在参数和效应量估计上的表现。并通过实际案例解释了2meMO模型的应用以及效应量的计算和解释。

submitted time 2020-10-21 Hits63Downloads22 Comment 0

5. chinaXiv:202010.00017 [pdf]

Cultivation effects on soil texture and fertility in an arid desert region of northwestern China

HE,Mingzhu; JI,Xibin; BU,Dongsheng; ZHI,Jinhu
Subjects: Geosciences >> History of Geosciences

In arid desert regions of northwestern China, reclamation and subsequent irrigated cultivation have become effective ways to prevent desertification, expand arable croplands, and develop sustainable agricultural production. Improvement in soil texture and fertility is crucial to high soil quality and stable crop yield. However, knowledge on the long-term effects of the conversion of desert lands into arable croplands is very limited. To address this problem, we conducted this study in an arid desert region of northwestern China to understand the changes in soil physical-chemical properties after 0, 2, 5, 10, 17, and 24 years of cultivation. Our results showed that silt and clay contents at the 17-year-old sites increased 17.5 and 152.3 folds, respectively, compared with that at the 0-year-old sites. The soil aggregate size fraction and its stability exhibited an exponential growth trend with increasing cultivation ages, but no significant change was found for the proportion of soil macroaggregates (>5.00 mm) during the 17 years of cultivation. The soil organic carbon (SOC) content at the 24-year-old sites was 6.86 g/kg and increased 8.8 folds compared with that at the 0-year-old sites. The total (or available) nitrogen, phosphorus, and potassium contents showed significant increasing trends and reached higher values after 17 (or 24) years of cultivation. Changes in soil physical-chemical properties successively experienced slow, rapid, and stable development stages, but some key properties (such as soil aggregate stability and SOC) were still too low to meet the sustainable agricultural production. The results of this long-term study indicated that reasonable agricultural management, such as expanding no-tillage land area, returning straw to the fields, applying organic fertilizer, reducing chemical fertilizer application, and carrying out soil testing for formula fertilization, is urgently needed in arid desert regions.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits28Downloads11 Comment 0

6. chinaXiv:202010.00018 [pdf]

Impacts of wind erosion and seasonal changes on soil carbon dioxide emission in southwestern Iran

KAMALI,Nadia ; SIROOSI,Hamid ; SADEGHIPOUR,Ahmad
Subjects: Geosciences >> History of Geosciences

Wind erosion is one of the main drivers of soil loss in the world, which affects 20 million hectare land of Iran. Besides the soil loss, wind erosion contributes to carbon dioxide emission from the soil into the atmosphere. The objective of this study is to evaluate monthly and seasonal changes in carbon dioxide emission in four classes i.e., low, moderate, severe and very severe soil erosion and the interactions between air temperature and wind erosion in relation to carbon dioxide emission in the Bordekhun region, Boushehr Province, southwestern Iran. Wind erosion intensities were evaluated using IRIFR (Iran Research Institute of Forests and Ranges) model, in which four classes of soil erosion were identified. Afterward, we measured carbon dioxide emission on a monthly basis and for a period of one year using alkali traps in each class of soil erosion. Data on emission levels and erosion classes were analyzed as a factorial experiment in a completely randomized design with twelve replications in each treatment. The highest rate of emission occurred in July (4.490 g CO2/(m2?d)) in severely eroded lands and the least in January (0.086 g CO2/(m2?d)) in low eroded lands. Therefore, it is resulted that increasing erosion intensity causes an increase in soil carbon dioxide emission rate at severe erosion intensity. Moreover, the maximum amount of carbon dioxide emission happened in summer and the minimum in winter. Soil carbon dioxide emission was just related to air temperature without any relationship with soil moisture content; since changes of soil moisture in the wet and dry seasons were not high enough to affect soil microorganisms and respiration in dry areas. In general, there are complex and multiple relationships between various factors associated with soil erosion and carbon dioxide emission. Global warming causes events that lead to more erosion, which in turn increases greenhouse gas emission, and rising greenhouse gases will cause more global warming. The result of this study demonstrated the synergistic effect of wind erosion and global climate warming towards carbon dioxide emission into the atmosphere.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits27Downloads11 Comment 0

7. chinaXiv:202010.00019 [pdf]

Applying seepage modeling to improve sediment yield predictions in contour ridge systems

LIU,Qianjin; MA,Liang; ZHANG,Hanyu
Subjects: Geosciences >> History of Geosciences

Contour ridge systems may lead to seepage that could result in serious soil erosion. Modeling soil erosion under seepage conditions in a contour ridge system has been overlooked in most current soil erosion models. To address the importance of seepage in soil erosion modeling, a total of 23 treatments with 3 factors, row grade, field slope and ridge height, in 5 gradients were arranged in an orthogonal rotatable central composite design. The second-order polynomial regression model for predicting the sediment yield was improved by using the measured or predicted seepage discharge as an input factor, which increased the coefficient of determination (R2) from 0.743 to 0.915 or 0.893. The improved regression models combined with the measured seepage discharge had a lower P (0.007) compared to those combined with the predicted seepage discharge (P=0.016). With the measured seepage discharge incorporated, some significant (P<0.050) effects and interactions of influential factors on sediment yield were detected, including the row grade and its interactions with the field slope, ridge height and seepage discharge, the quadratic terms of the field slope and its interactions with the row grade and seepage discharge. In the regression model with the predicted seepage discharge as an influencing factor, only the interaction between row grade and seepage discharge significantly affected the sediment yield. The regression model incorporated with predicted seepage discharge may be expressed simply and can be used effectively when measured seepage discharge data are not available.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits30Downloads12 Comment 0

8. chinaXiv:202010.00020 [pdf]

Untangling the influence of soil moisture on root pullout property of alfafa plant

ZHANG,Chaobo; LIU,Yating; LIU,Pengchong; JIANG,Jing; YANG,Qihong
Subjects: Geosciences >> History of Geosciences

Root pullout property of plants was of key importance to the soil reinforcement and the improvement of slope stability. To investigate the influence of soil moisture on root pullout resistance and failure modes in soil reinforcement process, we conducted pullout tests on alfalfa (Medicago sativa L.) roots at five levels (40, 30, 20, 10 and 6 kPa) of soil matric suction, corresponding to respectively 7.84%, 9.66%, 13.02%, 19.35% and 27.06% gravimetric soil moisture contents. Results showed that the maximal root pullout force of M. sativa decreased in a power function with increasing soil moisture content from 7.84% to 27.06%. Root slippage rate increased and breakage rate decreased with increasing soil moisture content. At 9.66% soil moisture content, root slippage rate and breakage rate was 56.41% and 43.58%, respectively. The threshold value of soil moisture content was about 9.00% for alfalfa roots in the loess soil. The maximal pullout force of M. sativa increased with root diameter in a power function. The threshold value of root diameter was 1.15 mm, because root slipping force was greater than root breaking force when diameter >1.15 mm, while diameter ≤1.15 mm, root slipping force tended to be less than root breaking force. No significant difference in pullout forces was observed between slipping roots and breaking roots when they had similar diameters. More easily obtained root tensile force (strength) is suggested to be used in root reinforcement models under the condition that the effect of root diameter is excluded as the pullout force of breaking roots measured in pullout tests is similar to the root tensile force obtained by tensile tests.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits27Downloads10 Comment 0

9. chinaXiv:202010.00021 [pdf]

Rehabilitation of degraded areas in northeastern Patagonia, Argentina: Effects of environmental conditions and plant functional traits on performance of native woody species

ZEBERIO,Juan M ; P?REZ,Carolina A
Subjects: Geosciences >> History of Geosciences

Degradation processes affect a vast area of arid and semi-arid lands around the world and damage the environment and people′s health. Degradation processes are driven by human productive activities that cause direct and indirect effects on natural resources, such as species extinction at regional scale, reduction and elimination of vegetation cover, soil erosion, etc. In this context, ecological rehabilitation is an important tool to recover key aspects of the degraded ecosystem. Rehabilitation trials rely on the use of native plant species with characteristics that allow them to obtain high survival and growth rates. The aim of this work was to assess the survival and growth of native woody species in degraded areas of northeastern Patagonia and relate them to plant functional traits and environmental variables. We observed high early and late survival rates, and growth rates in Prosopis flexuosa DC. var. depressa F.A. Roig and Schinus johnstonii F.A. Barkley, and low values in Condalia microphylla Cav. and Geoffroea decorticans (Gillies ex Hook. & Arn.) Burkart. Early survival rates were positively associated with specific leaf area (SLA) and precipitation, but negatively associated with wood density, the maximum mean temperature of the warmest month and the minimum mean temperature of the coldest month. Late survival rates were positively associated with SLA and soil organic matter, but negatively associated with plant height and precipitation. The temperature had a positive effect on late survival rates once the plants overcame the critical period of the first summer after they were transplanted to the field. Prosopis flexuosa and S. johnstonii were the most successful species in our study. This could be due to their functional traits that allow these species to acclimatize to the local environment. Further research should focus on C. microphylla and G. decorticans to determine how they relate to productive conditions, acclimation to environmental stress, auto-ecology and potential use in ecological rehabilitation trials.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits35Downloads17 Comment 0

10. chinaXiv:202010.00022 [pdf]

Prioritizing woody species for the rehabilitation of arid lands in western Iran based on soil properties and carbon sequestration

BAZGIR,Masoud ; OMIDIPOUR,Reza ; HEYDARI,Mehdi ; ZAINALI,Nasim ; HAMIDI,Masoud ; DEY,Daniel C
Subjects: Geosciences >> History of Geosciences

Plants are an important component in many natural ecosystems. They influence soil properties, especially in arid ecosystems. The selection of plant species based on their adaptations to site conditions is essential for rehabilitation of degraded sites and other construction sites such as check-dams. Other factors to be considered in species selection include their effects on soil properties and their abilities to meet other management objectives. The purpose of this study was to assess the effects of native (Populus euphratica Oliv. and Tamarix ramosissima Ledeb.) and introduced (Eucalyptus camaldulensis Dehnh. and Prosopis juliflora (Swartz) DC.) woody species on soil properties and carbon sequestration (CS) in an arid region of Iran. Soil sampling was collected at three soil depths (0–10, 10–20 and 20–30 cm) at the sites located under each woody species canopy and in an open area in 2017. Soil physical-chemical property was analyzed in the laboratory. The presence of a woody species changed soil characteristics and soil CS, compared with the open area. For example, the presence of a woody species caused a decrease in soil bulk density, of which the lowest value was observed under E. camaldulensis (1.38 g/cm3) compared with the open area (1.59 g/cm3). Also, all woody species significantly increased the contents of soil organic matter and total nitrogen, and introduced species had more significant effect than native species. The results showed that CS significantly increased under the canopy of all woody species in a decreasing order of P. euphratica (9.08 t/hm2)>E. camaldulensis (8.37 t/hm2)>P. juliflora (5.20 t/hm2)>T. ramosissima (2.93 t/hm2)>open area (1.33 t/hm2), thus demonstrating the positive effect of a woody species on CS. Although the plantation of non-native species had some positive effects on soil properties, we recommend increasing species diversity in plantations of native and introduced woody species to provide more diversity for the increased ecosystem services, resilience, health and long-term productivity.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits35Downloads17 Comment 0

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