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Copyright of Plateau Meteorology is the property of Plateau Meteorology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil moisture， as a key hydrological variable connecting the surface and atmospheric water and heat exchange， affects the land-air water and heat exchange and carbon cycle process.However， due to the difficulty in monitoring soil moisture in alpine mountain areas， there are some difficulties in related research.The study of time stability can reduce the difficulty of soil moisture acquisition by selecting representative points.In this study， the slope of Shangzhangfanggou grassland in Shiyang River basin of Qilian Mountain was selected to set up a high-density and high-time resolution soil moisture monitoring network to explore the temporal and spatial variation and temporal stability of soil moisture on the slope scale in alpine mountainous areas.The research results show that： （1） The surface soil moisture （10 cm， 15.90%） is significantly higher than that in the deep layer （50 cm， 11.78%）， and its temporal variability （CvT=19.46%） is also stronger than that in the deep layer （CvT=10.67%）， but its spatial variability （CvS=20.05%） is weaker than that in the deep layer （CvS=27.06%）.（2） The time stability Index of Temporal Stability （0.24） is stronger than that of the deep layer （0.34）， and the surface layer and the deep layer can represent the surface soil moisture of the slope through 3 or 5 soil moisture monitoring points respectively （R2> 0.90）.（3） Slope position and soil hydrological properties have obvious influence on time stability， and the time stability point is more likely to appear at the position with larger bulk density and smaller shape parameter n under the slope.The research results are helpful to better understand the temporal and spatial variation law， temporal stability characteristics and control function of soil moisture on slope in alpine mountain areas.

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The earth has been experiencing ever-increasing climatic fluctuation and extreme events for decades, and ecosystem structure and function have generally slipped into recession, resulting in significant impacts on economy and ecology. Ecosystem stability refers the ability of ecosystem to maintain or restore to normal structure and function, which is the key to maintain the ecosystem service function. However, due to the complexity of the ecosystem, the results of the research on the stability are still controversial. Here, the dimensionality, spatial patterns and influencing mechanisms of ecosystem stability were summarized from 58 relevant literatures. The multi-dimensional framework of ecosystem stability, definition and interrelationship of various stability indicators were discussed respectively as well as the effects of latitude, altitude, and position on stability. The dominant factors of the variation of stability at different scales and the effects of abiotic factors such as climate, nutrition and biological factors such as biodiversity on stability were also discussed. The results indicated that correlations between different components of ecosystem stability leaded to their generalization into three dimensionalities, including resistance, resilience and temporal stability. In addition, ecosystem stability was regulated by abiotic factors such as climate and nutrition as well as biological factors such as species richness and population variability. Stability and its influencing mechanisms showed strong spatial heterogeneity and scale dependence, which were mainly controlled by biological factors such as biodiversity at the site scale, and abiotic factors such as temperature, precipitation and radiation at the regional and global scales. Data source noise and unstandardized quantification methods were the main problems in stability study. In the future, with the applications of satellite remote sensing and other acquisition methods, the research field will be gradually expanding from local scale such as site to global scale such as region and continent, and a standardized stability assessment method can be formed. The large spatial scale research can effectively elucidate the general relationship between ecosystem stability and its response to various driving forces, providing a theoretical basis for the formulation of sustainable ecological protection policies. [ABSTRACT FROM AUTHOR]

Spatial variability of throughfall ( i.e. the non-uniform characteristics of throughfall at different canopy positions) and its temporal persistence ( i.e. time stability) are related to the quantity and efficiency of soil moisture replenishment, and affect plant competition and community succession dynamics by affecting resource availability. We carried out a meta-analysis with 554 papers (from 2000 to 2022) retrieved from Web of Science and China National Knowledge Infrastructure (CNKI) based on keyword search, quantified and compared the amount, spatial heterogeneity, and temporal stability characteristics of penetrating rain in different climate zones and plant functional types. Our results that throughfall proportion was lower in arid regions (72.0%±13.6%) than humid (75.1%±9.3%) and semi-humid areas (79.9%±10.4%). Cold climates had lower values (74.1%±14.6%) than temperate (74.2%±7.5%) and tropical climates (80.9%±14.6%). Shrubs (68.9%±14.9%) generally had lower throughfall proportion than trees (76.7%±9.1%). Broad-leaved trees (75.2%±11.1%) and conifers (75.1%±9.9%) showed similar throughfall proportions, as did evergreen (76.7%±10.0%) and deciduous species (74.7%±11.9%). Additionally, spatial variability (coefficient of variation) did not significantly differ across rainfall zones, temperature zones, or vegetation types. The spatial distribution of throughfall was relatively stable. Canopy structure was the dominant factor affecting temporal stability of throughfall. However, there was a lack of comparison between typical geographic units ( i.e. spatial units with basically consistent geographical environmental conditions) at various temporal scales. Future research should expand upwards to the summary of global spatial scale rules and downwards to the analysis of process based temporal scale mechanisms, to depict the dynamic distribution of penetrating rain and unify observation standards to enhance comparability of different studies, in order to efficiently promote research on canopy penetrating rain and provide ecological and hydrological basis for protecting nature, managing artificial activities, and restoring degraded ecosystems.

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil salinization is currently an important limiting factor on agriculture development in irrigation areas all over the world. Electrical conductivity (EC) is one of the main indicators which are used to determine whether the irrigation water will cause soil salinization. It is of important significance to study the temporal and spatial variation of groundwater EC for agricultural irrigation in irrigation districts. This study was conducted to examine the temporal stability and periodicity of groundwater EC in irrigation districts. To accomplish this, 51 observation wells were selected for analysis of groundwater EC in Luohuiqu irrigation district which was an important agricultural production base in Shaanxi Province, China. The 51 observation wells belonged to 3 different terraces which were Terrace 1, 2 and 3. The altitudes of the 3 terraces were >342-360, >360-369 and >370-388 m, respectively. The numbers of observation wells in Terrace 1, 2 and 3 were 26, 13 and 12, respectively. Water samples were collected from 2 m below the well water surface to measure the groundwater EC and temperature at each site. Well 36 (high EC) and 43 (low EC) were selected for long-term observation. A CTD-Diver (USA) groundwater level data logger was adopted for measuring and recording the groundwater EC, temperature and level. According to the long sequence monitoring results of groundwater EC for the 51 observation wells, relative difference analysis and non-parametric Spearman's rank correlation test were used to check for temporal stability of groundwater EC, while Morlet wavelet analysis was applied to study the periodic variation of groundwater EC and groundwater level of high and low salinity wells. The results indicated that the order of mean groundwater EC values of the 3 terraces at different time instants was Terrace 3 > Terrace 1 > Terrace 2. Significant difference existed among the mean groundwater EC values of the 3 terraces (P<0.01). The groundwater EC values of the 3 terraces at different time instants all indicated moderate spatial variability, with coefficient of variation (CV) values ranging from 44% to 75%. Based on the mean EC value of each observation well, 21 wells were slightly saline and 30 wells were moderately saline. The ranges of minimum and maximum value of groundwater EC were 0.08-0.14 and 0.50-1.00 S/m, respectively. The most of Spearman rank correlation coefficients for groundwater EC were close to 1 (P< 0.01), which indicated that the groundwater EC of the 3 terraces exhibited strong temporal stability. But the temporal stability of groundwater EC had little relationship with the terraces which the corresponding well sites belonged to. The representative locations of mean groundwater EC for Terrace 1, 2 and 3 were Well 40, 38 and 45, respectively. The representative location of mean groundwater EC for the entire study area was Well 2. Based on the Morlet wavelet analysis of the groundwater EC and water level of Well 36 (high EC) and 43 (low EC), both of the groundwater EC and water level showed periodic variations. The groundwater EC and water level indicated different vibration periods on different time scales for both Well 36 and 43. The change in groundwater EC on small time scales was mainly affected by lateral recharge sources. The groundwater EC and water level showed an obviously inverse phase on large time scales. In conclusion, the groundwater EC has strong temporal stability and periodicity in Luohuiqu irrigation district. The representative location with mean groundwater EC can be used to monitor the mean groundwater EC of the study area. Irrigation time should be fully considered in irrigation districts to avoid soil salinization. The representative location with mean groundwater EC can provide great guidance to determine the irrigation time quickly and accurately to reduce the risk of soil salinization. [ABSTRACT FROM AUTHOR]

Whether the assessment results of Contingent Valuation Method (CVM) have temporal stability is an important issue in examining the reliability of CVM findings, and also, is critical to decide whether CVM can be applied to evaluate the ecosystem services value in China. Taking the ecological restoration along the Caohejing River in Shanghai as a case, three CVM survey schemes with one month apart and two years apart were designed. Then, 426, 498, and 200 questionnaires in these surveys were comparatively analyzed, respectively. The mean values of the willingness to pay (WTP) from the three surveys were 14. 2, 14. 1, and 18. 0 RMB, and the median values were 5, 5, and 10 RMB, respectively. With the comparison of the WTP distribution and the main statistics, the analysis of the factors affecting the WTP, and the test of the significances of temporal variables, it was found that the CVM results from the surveys with one month apart had temporal stability, while those from the surveys with two years apart presented definite difference. [ABSTRACT FROM AUTHOR]