While a plethora of studies has been conducted to examine stress and its impact on mental health in western countries,research is scarce investigating the relationship between student challenge stress and health illne...While a plethora of studies has been conducted to examine stress and its impact on mental health in western countries,research is scarce investigating the relationship between student challenge stress and health illness in the context of Chinese colleges.No studies examined the moderating effect of self-efficacy on the relationship between challenge stress and health illness.This study attempted to investigate the relationships between these three variables among Chinese college students.Especially,this study focused on examining whether self-efficacy moderated the effect of perceived challenge stress on students’mental health.Also,the differences were tested between male and female students in terms of these three variables.A sample of 578 Chinese college students was recruited over an approximately 12-week period from 7 Chinese universities.An online survey link was dis-tributed through WeChat.The SPSS version 26 software was used to analyze the data.Results showed that there is no significant difference between genders in terms of perceived challenge stress,self-efficacy,and students’mental health.In addition,challenge stress was positively related to the students’mental health(β=0.35,p<0.01)while there was a negative association between self-efficacy and mental health(β=-0.41,p<0.01).Furthermore,self-efficacy plays a moderating role in the relationship between challenge stress and mental health(β=-0.11,p=0.02).Students with low self-efficacy tend to experience more mental health issues.It is suggested that Chinese colleges and universities pay more attention to students with low self-efficacy,either through faculty/staff interven-tions or peer counseling.Professors consider reducing students’academic stress to improve their mental health.展开更多
Meteorological drought is a natural hazard that can occur under all climatic regimes. Monitoring the drought is a vital and important part of predicting and analyzing drought impacts. Because no single index can repre...Meteorological drought is a natural hazard that can occur under all climatic regimes. Monitoring the drought is a vital and important part of predicting and analyzing drought impacts. Because no single index can represent all facets of meteorological drought, we took a multi-index approach for drought monitoring in this study. We assessed the ability of eight precipitation-based drought indices（SPI（Standardized Precipitation Index）, PNI（Percent of Normal Index）, DI（Deciles index）, EDI（Effective drought index）, CZI（China-Z index）, MCZI（Modified CZI）, RAI（Rainfall Anomaly Index）, and ZSI（Z-score Index）） calculated from the station-observed precipitation data and the Ag MERRA gridded precipitation data to assess historical drought events during the period 1987–2010 for the Kashafrood Basin of Iran. We also presented the Degree of Dryness Index（DDI） for comparing the intensities of different drought categories in each year of the study period（1987–2010）. In general, the correlations among drought indices calculated from the Ag MERRA precipitation data were higher than those derived from the station-observed precipitation data. All indices indicated the most severe droughts for the study period occurred in 2001 and 2008. Regardless of data input source, SPI, PNI, and DI were highly inter-correlated（R^2=0.99）. Furthermore, the higher correlations（R^2=0.99） were also found between CZI and MCZI, and between ZSI and RAI. All indices were able to track drought intensity, but EDI and RAI showed higher DDI values compared with the other indices. Based on the strong correlation among drought indices derived from the Ag MERRA precipitation data and from the station-observed precipitation data, we suggest that the Ag MERRA precipitation data can be accepted to fill the gaps existed in the station-observed precipitation data in future studies in Iran. In addition, if tested by station-observed precipitation data, the Ag MERRA precipitation data may be used for the data-lacking areas.展开更多
In this study we estimate agricultural water footprint and its components from consumption perspective in arid and semi-arid region like Iran. This study is based on blue water consumption in irrigated land. Iran has ...In this study we estimate agricultural water footprint and its components from consumption perspective in arid and semi-arid region like Iran. This study is based on blue water consumption in irrigated land. Iran has imported net virtual water about 11.64 billion cubic meters (bcm) as international crop trade in 2005-2006. Therefore, Iran has depended on virtual water imports. By conserving about 60% irrigation efficiency, the total water requirement to produce imported crops in Iran is nearly 20.78 billion cubic meters. It is nearly 9 percent of renewable water resources and 12.65% agricultural appropriated water which has added to internal water resources. Agricultural virtual water budget is about 112.78 Gm3/yr. Agricultural water footprint is 110.2 Gm3/yr. About 12.83% of agricultural water footprint of Iran is related to external water resources on the country boundaries. It means external water footprint. Water dependency, water self-sufficiency and water scarcity indexes in agricultural sector of Iran, are estimated 10.1%, 89.9% and 70.8%, respectively.展开更多
文摘While a plethora of studies has been conducted to examine stress and its impact on mental health in western countries,research is scarce investigating the relationship between student challenge stress and health illness in the context of Chinese colleges.No studies examined the moderating effect of self-efficacy on the relationship between challenge stress and health illness.This study attempted to investigate the relationships between these three variables among Chinese college students.Especially,this study focused on examining whether self-efficacy moderated the effect of perceived challenge stress on students’mental health.Also,the differences were tested between male and female students in terms of these three variables.A sample of 578 Chinese college students was recruited over an approximately 12-week period from 7 Chinese universities.An online survey link was dis-tributed through WeChat.The SPSS version 26 software was used to analyze the data.Results showed that there is no significant difference between genders in terms of perceived challenge stress,self-efficacy,and students’mental health.In addition,challenge stress was positively related to the students’mental health(β=0.35,p<0.01)while there was a negative association between self-efficacy and mental health(β=-0.41,p<0.01).Furthermore,self-efficacy plays a moderating role in the relationship between challenge stress and mental health(β=-0.11,p=0.02).Students with low self-efficacy tend to experience more mental health issues.It is suggested that Chinese colleges and universities pay more attention to students with low self-efficacy,either through faculty/staff interven-tions or peer counseling.Professors consider reducing students’academic stress to improve their mental health.
文摘Meteorological drought is a natural hazard that can occur under all climatic regimes. Monitoring the drought is a vital and important part of predicting and analyzing drought impacts. Because no single index can represent all facets of meteorological drought, we took a multi-index approach for drought monitoring in this study. We assessed the ability of eight precipitation-based drought indices（SPI（Standardized Precipitation Index）, PNI（Percent of Normal Index）, DI（Deciles index）, EDI（Effective drought index）, CZI（China-Z index）, MCZI（Modified CZI）, RAI（Rainfall Anomaly Index）, and ZSI（Z-score Index）） calculated from the station-observed precipitation data and the Ag MERRA gridded precipitation data to assess historical drought events during the period 1987–2010 for the Kashafrood Basin of Iran. We also presented the Degree of Dryness Index（DDI） for comparing the intensities of different drought categories in each year of the study period（1987–2010）. In general, the correlations among drought indices calculated from the Ag MERRA precipitation data were higher than those derived from the station-observed precipitation data. All indices indicated the most severe droughts for the study period occurred in 2001 and 2008. Regardless of data input source, SPI, PNI, and DI were highly inter-correlated（R^2=0.99）. Furthermore, the higher correlations（R^2=0.99） were also found between CZI and MCZI, and between ZSI and RAI. All indices were able to track drought intensity, but EDI and RAI showed higher DDI values compared with the other indices. Based on the strong correlation among drought indices derived from the Ag MERRA precipitation data and from the station-observed precipitation data, we suggest that the Ag MERRA precipitation data can be accepted to fill the gaps existed in the station-observed precipitation data in future studies in Iran. In addition, if tested by station-observed precipitation data, the Ag MERRA precipitation data may be used for the data-lacking areas.
文摘In this study we estimate agricultural water footprint and its components from consumption perspective in arid and semi-arid region like Iran. This study is based on blue water consumption in irrigated land. Iran has imported net virtual water about 11.64 billion cubic meters (bcm) as international crop trade in 2005-2006. Therefore, Iran has depended on virtual water imports. By conserving about 60% irrigation efficiency, the total water requirement to produce imported crops in Iran is nearly 20.78 billion cubic meters. It is nearly 9 percent of renewable water resources and 12.65% agricultural appropriated water which has added to internal water resources. Agricultural virtual water budget is about 112.78 Gm3/yr. Agricultural water footprint is 110.2 Gm3/yr. About 12.83% of agricultural water footprint of Iran is related to external water resources on the country boundaries. It means external water footprint. Water dependency, water self-sufficiency and water scarcity indexes in agricultural sector of Iran, are estimated 10.1%, 89.9% and 70.8%, respectively.
