ABSTRACT
Gully is a prominent indicator of land degradation in agroecosystems, functioning as a crucial pathway connecting upslopes to downstream channels. However, little is known about how gully regulates runoff, sediment, and nutrient loss processes in the catchment during snowmelt. In this study, we monitored these processes in situ at both the gully head (the upslope accumulated catchment of the gully head, CGH) and outlet of two representative and typical gully-dominated catchments (F1 and F2) during snowmelt in Mollisols region of Northeast China. Our results showed that runoff discharge of CGH and outlet exhibited a multi-peak trend during snowmelt, driven by the transition from snow melting to soil thawing. This transition resulted in distinct runoff patterns in both CGH and outlet, with significant differences in their response to air temperature. The total runoff yield of CGH accounted for 57.8 % in F1 and 40.6 % in F2 of the total runoff yield of the outlet. Notably, the peak sediment concentration displayed a marked lag compared to the peak runoff discharge, primarily dominated by the increased sensitivity of gully erosion after the thawing of gully slopes. Gully erosion was the main source of sediment yield in the catchment, contributing 98.2 % in F1 and 96.6 % in F2. Furthermore, nutrient concentrations exhibited a decreasing trend during snowmelt. The comparison of high nutrient concentrations in CGH and relatively low nutrient concentrations in outlet highlighted the gully's role in intercepting and diluting runoff nutrients. Hysteresis analysis confirmed the differential contribution of CGH and gully to nutrient sources. CGH accounting for 50.9 % and 93.3 % of runoff TN and runoff TP loss, while contributing only 8.3 % and 5.8 % to sediment TN and sediment TP loss, respectively. These findings offer valuable insights for effective erosion control and nonpoint source pollution management in gully-dominated agroecosystems during snowmelt.
ABSTRACT
BACKGROUND: The merits and drawbacks of moral relevance models of addiction have predominantly been discussed theoretically, without empirical evidence of these potential effects. This study develops and evaluates a novel survey measure for assessing moral evaluations of patient substance misuse (ME-PSM). METHODS: This measure was tested on 524 health professionals (i.e., physicians, nurses, and other health professionals) in California (n = 173), urban France (n = 102), and urban China (n = 249). Demographic factors associated with ME-PSM were investigated using analyses of variance (ANOVAs) and t-tests, with results suggesting that ME-PSM is higher among younger health professionals, nurses (when compared with physicians and other health professionals), and Chinese health professionals (when compared with French and American health professionals). RESULTS: Results provide preliminary support for the psychometric quality of the survey measure introduced in this study, including the existence of a single latent structure and partial invariance of collected data across countries. CONCLUSION: The survey measure for ME-PSM which was developed and tested in the current study appears to hold potential utility for use as a measure of moral views of patient substance misuse. With development, this measure may be used to examine moral evaluations, both as factors of stigma and of other clinical factors associated with the treatment of patients with substance use disorders.
