Subjects: Management Science >> Development and Management of Human Resources submitted time 2021-01-30
Abstract： " This paper investigates the relationship between the service sector and GDP in Denmark by adopting unit root test, Johansen cointegration test and Granger causality test with yearly data. The characteristics of service sector against agriculture sector, industry sector are also discussed. Under the monthly scale, the behaviours of the number of rented hotel room, power production and IPI are studied. The deindustralization caused by the development of tourism and the financial crisis of 2008 is discussed. The existence of periodic sponge effect between tourism and the manufacturing is found. By presenting several convinced explanations, this phenomenon will help to understand the dynamic mechanism of the economic developments. In the context of flexicurity labour market with flexible employment policies in Denmark, the unemployment issue against the tourism, power production and IPI is explored. Lastly, an approach to calculate periodic sponge effect index with some examples of Denmark’s data is proposed.
Peer Review Status:
Awaiting Review
Subjects: Statistics >> Applied Statistical Mathematics submitted time 2021-01-30
Abstract： " From a modelling perspective, our first contribution is to propose generalised linear regression GARMA (GLRGARMA) model and generalised linear regression SARMA (GLRSARMA) model with a innovative function of explanatory variables in order to extend GLGARMA to incorporate relevant information for model fitting and forecast in tourism area. Besides, the generalised Poisson (GP) distribution is adopted to accommodate over- equal- and under-dispersion for certain tourism data. Moreover, the performance of GLRGARMA model and GLRSARMA model with their nested sub-models are compared and evaluated using several well-known selection criteria. Our second contribution is to investigate the behaviour of tourism data. The pattern of long memory is examined. The analysis of Hurst exponent, ACF plot and periodogram plot shows that Gegenbauer long memory features are presented in tourism data. Furthermore, the distinct characteristics between Gegenbauer long memory and seasonality are demonstrated to reveal the that the GLRGARMA model is more suitable for modelling tourism data. Our third contribution is to derive a Bayesian approach via the efficient and user-friendly Rstan package in estimating our proposed models. For ML approach, the likelihood function is untractable because of involving very high dimensional integrals. Several monitors of convergence of posterior samples are discussed, such as the number of effective sample and bR estimate. The criteria for modelling performance are also derived.
Peer Review Status:Awaiting Review
Subjects: Hydraulic Engineering >> Basic Disciplines of Hydraulic Engineering submitted time 2021-01-30
Abstract： From the perspective of systematic thinking, this study applied the theories of information entropy and dissipative structure to comprehensively evaluate and analyze the evolution of the complex system of the Yellow River Basin over the past 40 years. With the concept of “Basin Development Index (BDI shortly)”, a preliminary scientific comprehensive evaluation method system of basin development quality is established. Results of the model calculation show that the ratio of per capita GDP in the basin to the national average and the total sedimentation in the lower Yellow River have occupied the largest weight for many years, and have had a relatively greater impact on the development of the basin in different historical periods. During the entire 40 years, the value of BDI has varied from 50.5 points in 1996 to 66.6 points in 2019, and has generally experienced a decreasing and an increasing stage. The evolution of BDI of Yellow River basin is consistent with the overall law of the basin development and has a great correlation with some major events happened in the basin. In addition, this research method can be extended to other fields such as regional governance. Compared with the current evaluation models mainly based on economic indicators, this novel methodology is more systematic and scientific, and will better serve the decision-making with more scientific thoughts.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Social Psychology submitted time 2021-01-29
Abstract： Self-esteem, as a core individual variable, has a long-standing inverse relationship with materialism. However, some studies have found that people with high self-esteem have higher materialism than those with low self-esteem, which contradicts existing research. In this connection, researchers need to rethink the said relationship. The heterogeneity hypothesis of high self-esteem holds that there are safe high self-esteem and fragile high self-esteem in high self-esteem groups, which may guide understanding this contradictory relationship. Therefore, the purpose of this study was to explore whether materialism was associated with different types of high self-esteem, namely, heterogeneous high self-esteem, and to explore whether the relationship would change under self-threat situations. To delve deeper into the impact of high self-esteem on materialism, three studies were conducted. In study 1, 420 college students from 4 universities were surveyed by questionnaire to explore the correlation between heterogeneous high self-esteem and materialism. Study 2 was aimed to verify the causal relationship, and the attractiveness threat in self-threat was activated to investigate whether the attractiveness threat played a moderating role in the relationship between heterogeneous high self-esteem and materialism where participants with fragile high self-esteem and safe high self-esteem were randomly assigned to the attractiveness threat group or the control group. They were asked to compare their attractiveness to the most and the least attractive images of the same sex selected from pre-test, respectively. Study 3 used intellectual threat as a form of self-threat priming and measured materialism at the implicit level where heterogeneous high self-esteem participants were randomly assigned to the intelligence threat group or the control group. The former completed 13 difficult questions from Raven’s Progressive Matrices and received negative feedback, while the latter did the opposite. The results of study 1 indicated that the relationship between high fragile self-esteem and materialism was positive, while the relationship between high safety self-esteem and materialism was negative. The materialism of people with high fragile self-esteem was significantly higher than those with high safety self-esteem. The results of study 2 suggested that attractiveness threat moderated the relationship between heterogeneous high self-esteem and materialism. Specifically, in the attractive threat scenarios, materialism of safety high self-esteem decreased, while materialism of fragile high self-esteem increased. In the non-attractive threat situation, the materialism difference between them was insignificant. This finding was further replicated in study 3 where intellectual threat moderated the relationship between heterogeneous high self-esteem and implicit materialism. Notably, in the context of intelligence threat, implicit materialism of safe high self-esteem declined, while implicit materialism of fragile high self-esteem increased. In the non-intelligence threat situation, the implicit materialism difference between them was insignificant. Therefore, from the perspective of heterogeneous high self-esteem, this study essentially proved the low materialism level of safe high self-esteem and high materialism level of fragile high self-esteem. It signifies that the two conclusions of previous studies are reasonable. If there exists more number of safe high self-esteem individuals among those high self-esteem persons, the relationship between high self-esteem and materialism is positive. On the contrary, if there is more number of vulnerable high self-esteem individuals, the relationship is negative, thereby solving the puzzle of the contradictory relationship between high self-esteem and materialism. Furthermore, this study can urge educators to pay more attention to the cultivation of children's safe high self-esteem rather than unquestioningly cultivating high self-esteem.
Peer Review Status:Awaiting Review
Subjects: Hydraulic Engineering >> River Silt Engineering submitted time 2021-01-29
Abstract： This article systematically summarized the development process of the operation mode of reservoirs on sediment-laden rivers in China since the 1950s, especially explained the application and design technology of "storing clean water and regulating muddy flow". The so-called " storing clean water and regulating muddy flow " application is to fully consider the changes in the incoming water and sediment process in the reservoir according to the requirements of the reservoir development task, and coordinate the impact of the sediment on the siltation form and effective reservoir capacity to maximize the coordination degree of the water-sediment relationship in the downstream river as the core. Through the comprehensive coordinated control of "blocking, regulating and discharging", the comprehensive utilization benefits of reservoirs can be brought. In design, in order to better exert the reservoir regulation function, it is necessary to consider the demand for storage capacity of water and sediment regulation, and set up sufficient water and sediment regulation storage capacity to reduce the adverse impact of the forced sediment discharge of the reservoir on the downstream water-sediment relationship. The storage capacity distribution design is based on the rules of “deep channel for sediment regulation, medium channel for benefit and high channel for flood regulation”, to avoid the use of effective reservoir capacity due to sedimentation. Rivers with ultra-high sediment content should set abnormal sediment discharge bottom outlets to form a "normal + abnormal" double sediment erosion datum plane, to realize the recycling of part of the sediment storage capacity, and the integrated utilization of sediment storage capacity and water and sediment regulation storage capacity. Reservoir should adopt water and sediment separation development method, which is “"mainstream large reservoirs for sediment regulation, tributary small reservoirs for water supply", in rivers with super high sediment content to solve the contradiction between effective reservoir capacity maintenance and water supply regulation. On the basis of achieving long-term preservation of effective storage capacity, "storing clean water and regulating muddy flow" better takes into account the needs of reservoir water and sediment regulation in sediment-laden rivers. The results will provide guidance and reference for the reservoir engineering design and operation of sediment-laden river, in the current and future periods.
Peer Review Status:Awaiting Review
Subjects: Astronomy >> Astrophysical processes submitted time 2021-01-29 Cooperative journals: 《天文研究与技术》
Abstract：为了验证逆康普顿机制中的主导过程，以及主导过程中软光子的起源。我们通过文献收集了75个平谱射电类星体多波段的（准）同时性数据，并利用对数抛物线函数拟合了频谱能量分布，分析同步峰流量与逆康普顿峰之比和多普勒因子的关系，运用自举法计算了样本的种子因子分布用以调查软光子的起源。分析结果如下：(1)、在轻子模型框架下，整个样本与子样本log(〖U_B (νF_ν )〗_EC⁄〖U_ext (νF_ν )〗_syn )与logδ的显著相关性表明平谱射电类星体的高能辐射优先由外康普顿过程主导。(2)、对于相对低同步峰峰频的种群，观测的种子因子分布与理论上尘埃环的种子因子范围相交表明其逆康普顿过程中的软光子很可能由尘埃环主导，而对于相对高同步峰峰频的种群，观测的种子因子超过了宽线区或尘埃环种子因子的范围，因此我们还无法确定其软光子的来源。
Subjects: Astronomy >> Astrophysical processes submitted time 2021-01-29 Cooperative journals: 《天文研究与技术》
Abstract：小波变换去噪只对信号的低频部分进行分解和处理，忽略了信号的高频部分的分解与处理，无法对信号的整个频段信息的有效提取，进而影响脉冲星信号去噪的效果。鉴于此，本文提出利用小波包阈值法对脉冲信号进行分析，针对小波包分解后的系数选用不同的阈值函数处理。实验结果表明，使用该方法进行脉冲星信号的去噪效果得到了提高，其中脉冲星信号的信噪比、峰值信噪与平滑度指标都有相应的得到了改善，为脉冲信号的去噪提供了一种新的思路。
Subjects: Astronomy >> Astrophysical processes submitted time 2021-01-29 Cooperative journals: 《天文研究与技术》
Abstract： 南极高原拥有独特的天文观测条件，为对南极中山站夜天文观测条件进行实测研究，中国科学院云南天文台特殊研制了一套具有耐低温、自动除雪除霜等适应南极气候性能的全自动全天信息采集系统。该系统可以提供实时的全天云量、天光背景和全天图像，并可将信息推送到网页实时显示。本文介绍了这套系统的研制，及为适应南极气候所进行的耐低温实验。后统计分析了中山站2016-2017两个年度的全天信息数据，初步得出中山站的可观测小时数、可观测夜数、天光背景及温湿度条件。
Subjects: Psychology >> Developmental Psychology submitted time 2021-01-28
Abstract： Developmental motor disorders are the common feature of autism spectrum disorder (ASD). Through a systematic review of the neuroscience literature, it is found that the alteration in the concentration of GABA and of serotonin and the abnormal expression of GABA-related protein and of shank protein led to not only the defects of the development of the central nervous system but also the synaptic excitation/inhibition imbalance, thus in turn resulting in the changes of the functional connectivity between cerebellum and motor cortex in children with ASD. The abnormalities in the structure of the cerebellum, basal ganglia, and corpus callosum had a negative impact on the whole-brain connectivity in children with ASD. The disorders in neurobiochemical mechanisms and the abnormalities of brain structure together triggered abnormal brain function of children with ASD, which ultimately resulted in developmental motor disorders. In addition, the common neural basis shared by the developmental motor disorders and the core symptoms of ASD mainly included the mirror neuron dysfunction, the abnormalities of the thalamus, the basal ganglia, the cerebellum and mutations of SLC7A5 and PTEN. Future researches need to focus on other neurotransmitters closely related to motor, such as acetylcholine and dopamine, to explore the dynamic mechanism and formation of the neural network of developmental motor disorders, and to analyze the interaction between the underlying neural mechanisms of motor developmental disorders and that of core symptoms of autism.
Subjects: Psychology >> Management Psychology submitted time 2021-01-28
Abstract： Satiation refers to the subjective emotional experience in which consumers' sense of utility, enjoyment and satisfaction from the same product or service decrease over time, and negative perception gradually suppresses positive perception. In order to alleviate or prevent satiation, consumers will take the behavior of brand switching, variety seeking and controlling consumption cycle. Therefore, satiation has become the main obstacle for enterprises or shops to cultivate customer loyalty. Foreign literatures have divided the types of satiation from the generation process, functional response, cognitive state and attribute perception, and analyzed the theories of hedonic adaptation, diminishing marginal utility, cognitive dissonance and optimal stimulation level to explain the generation of satiation，then explored the inducing factors of the physiological and psychological satiation, verified the moderating effects of environmental factors and individual factors on consumers’ satiation. At the same time, it discusses the mitigation strategies or behavioral responses of consumers to satiation. Finally, the research ideas, characteristics and shortcomings of the existing literature are reviewed, and the future research direction is proposed.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Social Psychology submitted time 2021-01-28
Abstract： Previous studies have demonstrated the possibility that when people are in standing than sitting postures, they have a stronger cognitive control propensity, making them inclined to agree more to sacrificing one innocent and saving more people. Furthermore, this postural effect can be moderated by dual processes. In three studies, participants read dilemma scenarios followed by a proposed behavior to sacrifice one innocent and save five or more people. The participants in sitting or standing postures were asked whether the described action was morally acceptable (moral judgment) and whether they would perform the described action (moral action). The results demonstrated that participants were more approving of the behavioral proposal in the moral action perspective than in the moral judgment perspective across the three studies. The hypothesized postural effect was found in a field study (Study 1) and replicated in a pre-registered replication study (Study 2) and further supported in an experimental study (Study 3). Compared with those in sitting postures, participants in standing postures expressed higher approval of the behavioral proposal compared to their sitting counterparts. Furthermore, the postural effect was dismissed when participants made moral decisions with a dual task to increase cognitive load, and it was reversed when they made moral decisions after deliberate consideration of the behavioral proposal (Study 3). The present research supports and extends the dual-process morality theory by demonstrating that body posture can affect moral decision-making; it also offers novel evidence revealing the moderating role of dual process on embodiment effects. It enriches our knowledge that morality is evolutionarily embodied in postures and that the dual process can moderate embodiment effects.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Developmental Psychology submitted time 2021-01-27
Abstract：发展性阅读障碍是指个体在智力正常并且不缺乏学校教育的情况下，仍无法获得与年龄相匹配的阅读技能的一种学习障碍，其缺陷的本质一直是研究者争论的焦点。大量研究显示，阅读障碍者常表现出听觉时间加工损伤。在行为层面，阅读障碍者难以辨别快速、连续呈现刺激的顺序以及刺激本身的动态时间特征。在神经层面，阅读障碍者诱发的失匹配负波更弱且具有异常的神经同步加工。这些损伤同时存在于对言语和非言语刺激的加工中，表明听觉时间加工缺陷非言语加工所特有。未来的研究还需阐明以下几个问题：1）阅读障碍的听觉时间加工缺陷发生在哪些时间窗口，随年龄增长如何变化；2）阅读障碍听觉时间加工缺陷在神经层面的时间进程是怎样的；3）听觉时间加工缺陷是否为阅读障碍的核心缺陷。
Subjects: Psychology >> Developmental Psychology submitted time 2021-01-26
Abstract： Adolescent depresseion and non-suicidal self-injury (NSSI) are major public health concerns worldwide. Identifying the developmental trajectories that lead to these problems can help to design effective prevention programs. Previous research has reported 3 to 6 developmental trajectories of depressed mood and 3 to 4 developmental trajectories of NSSI. However, depressed mood and NSSI often co-occur, and little research has explored their joint developmental trajectories. Importantly, various interpersonal factors may affect the development of both depression and NSSI. For example, research has suggested that adolescents’ relationships with their parents and peers plays a crucial role in developing depression and NSSI. Yet, to date, no research has examined the effect of teacher-student relationships. Therefore, the present study aimed to characterize the joint developmental trajectories of adolescents’ depressed mood and NSSI, and examine the importance of peer, parent and teacher relationships in these trajectories. A sample of 859 adolescents (56.43% males; Mage = 14.73, SD = 0.43) was followed up for three years from the first year to the third year of junior middle school, in a central western Chinese city, Xi’an. Participants reported their depressed mood and NSSI at three time points, one year apart. They also completed self-measures of friendship quality, parent relationships and teacher relationships at Time 1, and nominated their classmates’ peer status at Time 1. All measures were conducted anonymously and approved by school administrators. Latent class growth analysis was used to identify the independent and joint developmental trajectories of depressed mood and NSSI, while logistic regression was used to examine the effects of relations with parents, peers and teachers. We found 4 developmental trajectories of depressed mood and 3 developmental trajectories of NSSI. Moreover, we identified three joint developmental trajectories of adolescents’ depressed mood and NSSI. The first trajectory class (91%), labeled “low depression- low NSSI- stable”, included adolescents with low depression and NSSI across all timepoints. The second trajectory class (5%), labeled “moderate depression-moderate NSSI- decrease”, consisted of adolescents whose depression and NSSI were moderate at baseline and then decrease over time. The third trajectory class (4%) labeled “low depression- low NSSI- increase”, consisted of adolescents whose depression and NSSI were low at baseline and then increase over time. Furthermore, the level of parental psychological control differentiated adolescents in the first joint trajectory class from those in the second and third joint trajectory class. In addition, peer acceptance distinguished adolescents in the third joint trajectory class from those in the first and second joint trajectory class. This study examined the independent and joint developmental trajectories of depressed mood and NSSI during adolescence and revealed important roles of parents and peers in these developmental processes. These findings extend our knowledge of the dynamic relationships between depression and NSSI, and the interpersonal factors that influence this. By improving adolescents’ relationships with their parents and peers, school practitioners can reduce rates of depression and NSSI in this group.
Peer Review Status:Awaiting Review
Subjects: Information Science and Systems Science >> Basic Disciplines of Information Science and Systems Science submitted time 2021-01-26
Abstract： It is an important decision-making basis for the high-quality development of the whole basin in mastering the evolution of the spatio-temporal pattern in the economic development of the Yellow River Basin systematically. At present, GDP is the main reference to measure the pattern of economic development, however, GDP statistics have the disadvantages of not uniform caliber and low spatial resolution, it is difficult to accurately characterize the evolution pattern of economic development in space and time. The nightlight data reflect it effectively with its relatively objective characteristics. Through the correction and processing of the national nightlight data from 1992 to 2013, this paper obtains the national and watershed nightlight data images, conducts economic spatial aggregation analysis, and compares and analyzes the relevant factors. The results show that the areas with high economic spatial aggregation are distributed near the Yellow River channel, from the upper reaches to the lower reaches of the Yellow River, the heat intensity is gradually increasing, and the provincial capital city is the core area, spreading outwards, showing the tendency of the polymerization area to disperse to the surrounding area under the condition that the polymerization of the old polymerization point is intensified; The basin development index BDI has a certain correlation, the overall trend of nightlight data in 9 provinces of the basin is basically consistent with the change trend of the national nightlight data, showing a steady upward trend, but the overall value is lower than the national nightlight data, the high-quality development of the Yellow River basin is imminent.
Peer Review Status:Awaiting Review
Subjects: Hydraulic Engineering >> Basic Disciplines of Hydraulic Engineering submitted time 2021-01-26
Abstract： Ecological conservation and high-quality development of the Yellow River Basin has become a major national strategy. The socio-economic development of the Yellow River Basin is one of the main factors affecting the governance and protection of the Yellow River. It has become a scientific issue to analyze the law of socio-economic development of the Yellow River Basin and give countermeasures. . This paper selects 12 socio-economic characteristic indicators from four perspectives: population characteristics, residents’ quality of life, economic growth level, and regional industrial structure. The social development index (SDI) is calculated by the entropy method, and the Yellow River Basin is quantitatively analyzed in the past 40 years. The research shows that the social development index of the Yellow River Basin in the past 40 years shows a trend of "down stable up", especially after 2012, with the gradual maturity of economic transformation, the social development of the Yellow River Basin is on the whole better. "
Peer Review Status:Awaiting Review
Subjects: Hydraulic Engineering >> Basic Disciplines of Hydraulic Engineering submitted time 2021-01-26
Abstract： The Yellow River is the mother river of Chinese nation. In recent years, the inflow and sediment of the Yellow River have decreased, with extreme climate events occurred frequently, the boundary conditions have changed greatly. As the rapid economic and social development, it is necessary to carry out river health diagnosis under the changing environment. This research adopted information entropy and entropy weight methods to study the evolution characteristics of the healthy development of the Yellow River basin. Results showed that: (1) The river system presented healthy in 1980~1986, unhealthy in 1987~1999 and sub-healthy in 2000~2019. (2) The river system showed a healthier trend within 1980~1984, an increasingly unhealthy trend in 1984~1996, while following a good development trend in 1996~2019. (3) The flood discharge capacity of the main channel of the Ningxia-Inner Mongolia reach and the total amount of erosion and deposition in the downstream are the most sensitive factors.
Peer Review Status:Awaiting Review
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2021-01-26 Cooperative journals: 《干旱区研究》
Abstract：以陆地棉材料（中07）和海岛棉材料（新海20）构建的F2:6陆海重组自交系群体为试验材料，分别于2018年、2019年的7月份在石河子144团采用田间干旱胁迫的方法，在花铃期对棉花陆海重组自交系群体进行干旱胁迫处理，通过测定农艺性状和产量相关性状，采用方差分析、主成分分析、聚类分析等相结合的方式，对陆海重组自交系群体进行抗旱性鉴定及评价。由主成分分析可知，陆海重组自交系群体在干旱胁迫状态下铃数、皮棉、有效果枝数和衣分变化较为明显。根据抗旱性度量值（D 值）进行聚类，将陆海重组自交系群体材料划分为4个类群：第Ⅰ类群为抗旱型，是HL-44、HL-48、HL-13等16个株系；第Ⅱ类群为中抗旱型，是HL-21、HL-8、HL-19等19个株系；第Ⅲ类群为干旱敏感型，是HL-11、HL-12、HL-3等29个株系；第Ⅳ类群为干旱极敏感型，是HL-10、HL-18、HL-31等8个株系。并鉴定出亲本中07属于抗旱型材料，新海20属于抗旱敏感材料。同时发现群体材料中有比亲本中07抗旱性更强的株系有5个，在抗旱型类群；比亲本新海20抗旱性更敏感的株系有8份，在极敏感型类群。说明该陆海重组自交系群体在抗旱性方面不仅有亲本陆地棉和海岛棉的遗传特性，还有超越亲本的遗传特性。为今后研究海陆重组自交系群体的抗旱性提供了基础。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2021-01-26 Cooperative journals: 《干旱区研究》
Abstract：新疆南部地区淡水资源短缺，浅层地下咸水及灌溉排水资源相对丰富，研究淡咸水混合灌溉对棉花生长及产量的影响，以期获得一套简易的应用模式，在极端干旱年份对于缓解新疆南部棉花种植地区的干旱损失具有重要意义。以灌溉地表水（矿化度0.38～0.75 g·L-1）为对照与排水渠咸水(矿化度9.81～11.81 g·L-1)按照不同比例混合，设置6种不同梯度的灌溉水，即淡咸比1:0（对照）；淡咸比4:1（处理1）；淡咸比3:2（处理2）；淡咸比2:3（处理3）；淡咸比1:4（处理4）；淡咸比0:1（处理5），对棉花进行大田灌溉试验。结果表明：（1）随着灌溉水矿化度增加，棉花的生理性状呈现下降趋势。与对照相比，处理1灌溉水对棉花生长的影响较小，棉花产量较对照下降11.85%。（2）灌溉水分生产效率随着灌溉水矿化度的升高而降低，处理1较对照减少最少。（3）不同微咸水处理下10～40 cm土壤盐分呈现累积现象，其中对照最后1次灌水后的土壤盐分较第1次灌水前增加14.08%，处理5增加最多为173.08%。灌溉水配比4:1即矿化度为2.36～3.39 g·L-1时对棉花生长、产量、灌溉水分生产效率及土壤盐分影响较小。说明在干旱缺水时期采用适当的咸淡混合灌溉方式，对于缓解区域水资源短缺，保证棉花产量具有重要的作用。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2021-01-26 Cooperative journals: 《干旱区研究》
Abstract：协调马铃薯与绿肥作物对水分的利用，是协同实现二者间作提高半干旱区马铃薯产量和提升耕地质量的关键。于2017—2018年在西北黄土高原半干旱区布置定位试验，间作箭舌豌豆设计6月10日（PS1）、6月26日（PS2）和7月10日（PS3）3个播期，以马铃薯单作（P）为对照，测定土壤水分、生物量、马铃薯叶片叶绿素相对含量（Soil and Plant Analyzer Development，SPAD）、冠层温度和产量等指标。结果表明，与P相比，平水年（2017年）PS1降低了马铃薯花期120~160 cm土层和块茎膨大期20~40 cm土层的土壤贮水量，PS2和PS3则增加了块茎膨大期140~200 cm、收获期0 ~ 80 cm土层的土壤贮水量；间作提高了丰水年（2018年）土壤贮水量。平水年PS1花前耗水量最高，较PS3提高了15.7%；丰水年PS3最高，较PS1增加了17.9%，但均和P、PS2无显著差异；P的花后耗水量在平水年分别较PS1、PS2 和PS3 增加了70.9%、48.6%和32.0%；PS3 的花后耗水量在丰水年分别较P、PS1 和PS2 增加了24.3%、23.1%和38.1%，均达到显著差异。PS2和PS3的地上生物量较P在2017和2018年分别增加了1.1%~12.4%和11.0%~13.2%，且PS3在平水年显著提高了水分利用效率（Water Use Efficiency, WUE）。平水年P和PS3的产量无显著差异，但显著高于PS1和PS2；丰水年P、PS2和PS3的产量无显著差异，但显著高于PS1。因此，半干旱区马铃薯间作的箭舌豌豆适宜播期在6月下旬到7月上中旬，在不降低马铃薯块茎产量的基础上增加地上部生物量，并显著提高平水年马铃薯的WUE。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2021-01-26 Cooperative journals: 《干旱区研究》
Abstract：为探明湖泊滨岸对矿井水中氮素的截留与缓冲作用及其与滨岸土壤氮素空间分布间的关系，以宁夏灵武市羊场湾煤矿矿井水排放湖泊——园疙瘩湖为研究对象，测定了该湖水滨区域、近岸陆域和自然区域土壤中8种氮素的含量和土壤酶的活性，分析了水滨区域和近岸陆域与自然区域相比的土壤氮素变化系数及其随距矿井水排放口距离远近的变化规律。结果表明：园疙瘩湖滨岸土壤氮素空间分布存在异质性；相比较而言，水滨区域与周边自然区域的土壤氮素分布特征差异较大，而近岸陆域与周边自然区域的差异较小；相较于无机态氮，有机态氮的空间异质性更强；各有机氮形态中，颗粒物有机氮多被截留于离岸最近的水滨区域，而氨基酸氮和可溶性有机氮则需要更为宽阔的截留区域；水滨区域对颗粒物有机氮的截留效应随着距矿井水排放口距离的增加而降低；水滨区域和近岸陆域对氨基酸氮的截留效应在1400 m内逐渐降低，而在1400 m后趋于稳定；水滨区域和近岸陆域对可溶性有机氮的截留效应与其离矿井水排放口的距离无关，这可能是因为可溶性有机氮的易溶解特性使其随水体的迁移性较强，滨岸带土壤虽在吸附和缓存可溶性有机氮中发挥了一定的作用，但其较强的迁移性致其在滨岸带土壤中的分布较为均一；滨岸土壤氮素的空间异质性与土壤酶活性无关。综上可知，湖泊滨岸土壤对矿井水中有机态氮具有截留作用，且该截留作用多发生在距矿井水排放口1400 m的滨岸带内，滨岸土壤对矿井水中氮素的截留作用亦是滨岸土壤氮素空间分布异质性的主导因素。本研究结果可为指导矿井水排放路径的设计及矿井水资源的合理开发与利用提供指导。
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