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1.
Huan Jing Ke Xue ; 44(12): 6767-6777, 2023 Dec 08.
Artículo en Chino | MEDLINE | ID: mdl-38098402

RESUMEN

Taking the Tugeligaole sub-basin of the Jilantai Salt Lake Basin in Inner Mongolia as the typical study area, the groundwater samples of 22 points were collected, and their main characteristic indexes were tested during the wet season and the dry season separately in 2021. Mathematical statistics, Piper triangular diagrams, a Gibbs plot, ionic relations, and factor analysis were used to analyze and discuss the hydrochemical characteristics and formation mechanism of groundwater in different periods. Based on the evaluation of the groundwater quality using the water quality index(WQI) method, the potential risks of groundwater Cr6+ and F- were evaluated using the health risk evaluation model. The results showed that the groundwater was overall weakly alkaline; the dominant anions and cations during the different periods were Cl- and Na+, and the water chemistry type was mainly Cl--Na+; the groundwater quality was generally good, and the difference in water quality between the wet season and the dry season was not significant; adults and children had higher carcinogenic health risks in the dry season than that in the wet season, and the health risks of children were significantly higher than those in adults. The maximum carcinogenic health risk of drinking water exposure to Cr6+ in adults and children was higher than the maximum acceptable risk level(5×10-5). The chemical evolution of groundwater was mainly affected by evaporative concentration, evaporative salt rock dissolution, and cation exchange, and the main control factors were evaporative concentration(contribution rate of 54.19%), native geological environment factors(contribution rate of 12.99%), and carbonate rock dissolution(contribution rate of 11.66%). The study results have significance to some degree to the sustainable exploitation and utilization of groundwater resources and environmental protection of the salt lake basin.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Niño , Adulto , Humanos , Monitoreo del Ambiente , Lagos , Calidad del Agua , Carbonatos , China , Contaminantes Químicos del Agua/análisis
2.
Huan Jing Ke Xue ; 44(7): 3855-3863, 2023 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-37438284

RESUMEN

In this study, we collected precipitation from February 2020 to February 2022 and the surface water and groundwater in the wet (August) and dry (October) periods of 2021 in the Shandian River Basin. Stable isotope technology was used to analyze the temporal and spatial changes in the hydrogen and oxygen stable isotopes of the "three waters" in the basin to explore the relationship between water isomorphs and environmental factors and to reveal the water conversion relationship using the end element mixing model. The results showed that the slope and intercept of the local precipitation line were smaller than the local atmospheric precipitation line. The water vapor mainly came from westerly water vapor, polar air mass, and East Asian monsoon circulation. The precipitation isotope had a significant temperature effect. In terms of time, the isotopes of surface water and groundwater were more enriched in the dry season than those in the wet season, and the d-excess values of surface water and groundwater were lower than the global average, indicating strong local evaporation. Spatially, the δ18O value of the rivers had the same change characteristics in the wet and dry seasons, showing gradual enrichment from the upstream to the downstream, and the groundwater δ18O high value area was unevenly distributed in space, with groundwater δ18O values becoming more depleted with the increase in burial depth. The highest slope of the groundwater water line was 7.87 in the wet season, which was very close to the slope of the local atmospheric precipitation line and river water line, indicating that there was a complex hydraulic connection between the "three waters" in the wet season. The surface water in the study area was mainly supplied by precipitation during the wet season and then by groundwater runoff. These results can provide a theoretical basis for revealing the hydrological cycle in arid and semi-arid areas.

3.
Ying Yong Sheng Tai Xue Bao ; 32(6): 1980-1988, 2021 Jun.
Artículo en Chino | MEDLINE | ID: mdl-34212602

RESUMEN

We examined the characteristics of water use in typical tree species of arbor and shrub in Hunshandake Sandy Land, Populus cathayana and Salix gordejevii, in the different seasons, with the aim to provide theoretical basis for the structural optimization of the artificial shelterbelt. Samples of precipitation, soil water, groundwater and stem water of the two vegetation were collected, and their distribution characteristics of δD-δ18O were analyzed by hydrogen and oxygen stable isotope technology. The contribution rate of these potential water source to the arbor and shrub species were calculated using multi-source linear mixing model. The precipitation equation line in the study area was δD=7.84δ18O+9.12, while soil moisture lines in the dry and wet season were δD=3.56δ18O-41.28 and δD=4.30δ18O-42.02, respectively. The δD-δ18O of soil water and stem water in the two seasons were lower than the precipitation δD-δ18O, indicating that both of them were strongly affected by the evaporation. Soil water contents in the shallow layer were strongly affected by rainfall and evaporation, with substantial fluctuation. With the increases of soil depth, soil water content tended to be stable, and the hydrogen and oxygen isotope in each soil layer showed significant differences. In the dry season, P. cathayana mainly utilized soil water in 0-40 cm and 120-200 cm layers, with contribution rates of 50.2% and 31.5%, respectively. S. gordejevii mainly absorbed soil water in 20-40 cm and 60-100 cm layers, and the contribution rates were 53.2% and 22.9%, respectively. In the wet season, the greatest contribution of soil water to P. cathayana was mainly in the 0-40 cm soil layer, accounting for 72.8%. S. gordejevii was mainly in the 0-20 cm soil water, evenly utilized the deeper soil water and groundwater. Due to the differences in root depth and distribution of the arbor and shrub, their water use strategies differed in different seasons, which was conducive to the stability of the shelterbelt community and tree species coexistence in Hunshandake Sandy Land. We proposed that the mixed planting species with different root depth should be considered in the future planting of artificial shelterbelt, which would help rationally utilize water resources and maintain the stability of sandy land ecosystem.


Asunto(s)
Ecosistema , Suelo , China , Isótopos de Oxígeno/análisis , Agua
4.
Ying Yong Sheng Tai Xue Bao ; 32(3): 860-868, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33754551

RESUMEN

Inner Mongolian steppe is one of the ecological barriers in China. The variation of water resources is very important for the development of social-economy and the protection of eco-environment. We collected 254 water samples of precipitation, river, and shadow groundwater during wet-season and dry-season of 2018-2019 from Balaguer River watershed and meansured the physical-chemical indicators, δD and δ18O of water samples. The stable isotope technology, mathematical statistics, and the inverse distance weighting method were used to analyze the stable isotope composition, spatial-temporal variation, and impact factors. Moreover, the d-excess and the isotopic mixing ratio formula were used to analyze the conversion characteristics of different water and to identify their environment driving variables. The results showed that δD and δ18O of precipitation, river and shallow groundwater were higher in wet season than in dry season. The driving factors of different water transformation in the watershed were air temperature, altitude, and groundwater depth. Altitude was significantly negatively correlated with river δD, and the δD and δ18O of groundwater. δD and δ18O of groundwater fluctuated significantly in the area with groundwater depth less than 10 m, but were stable in other areas. There was a positive correlation between precipitation δ18O and air temperature. The d-excess in wet season was higher than that in dry season, with a decreasing distribution characteristic from southern to northern part in the study area. More than 50% river in upper stream came from precipitation, while more than half river water converted to groundwater, with different recharge-drainage relationships existed between surface water and groundwater in different river reaches.


Asunto(s)
Agua Subterránea , Ríos , China , Monitoreo del Ambiente , Isótopos de Oxígeno/análisis , Agua
5.
Zhonghua Wai Ke Za Zhi ; 48(2): 88-92, 2010 Jan 15.
Artículo en Chino | MEDLINE | ID: mdl-20302723

RESUMEN

OBJECTIVE: To analyze the impact of diabetes mellitus on the clinicopathological factors and prognosis of patients with colorectal cancer. METHODS: A total of 599 patients with colorectal cancer treated between January 2000 and June 2007 were collected retrospectively. The patients were divided into diabetes mellitus (DM) group and non-diabetes mellitus (NDM) group. The pathologic factors data was compared between the two groups, and the Logistic multivariable analysis was performed. The Cox regression model analysis of prognosis data was applied in 402 patients who underwent radical surgery without preoperative neoadjuvant therapy. RESULTS: A total of 58 cases (9.7%) developed diabetes mellitus. Significant differences was found in the body-weight, age, hypertension between the two groups (P < 0.05), while no significant differences in the pathologic factors, such as tumor differentiation, invasion depth, lymph node involvement, TNM stage and lymphovascular invasion was found between the two groups (P > 0.05). There was no significant correlation between diabetes mellitus and the pathologic factors on the Logistic analysis (P > 0.05). Among the patients underwent radical surgery directly, neither disease progression curve (P = 0.521) nor overall survival curve (P = 0.909) presented significant differences between the two groups. It's not shown that diabetes mellitus was significantly associated with the prognosis of patients with colorectal cancer by using Cox regression analysis (P = 0.991). CONCLUSIONS: Diabetes mellitus does not significantly influence the clinicopathological factors and the prognosis of colorectal cancer in patients receiving radical surgery, and it requires more investigation.


Asunto(s)
Neoplasias Colorrectales/patología , Diabetes Mellitus , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
6.
Zhonghua Wei Chang Wai Ke Za Zhi ; 11(3): 249-52, 2008 May.
Artículo en Chino | MEDLINE | ID: mdl-18478470

RESUMEN

OBJECTIVE: To compare the long-term efficacy of procedure for prolapse and hemorrhoids (PPH) and Milligan-Morgan hemorrhoidectomy (MMH) in the treatment of III and IV degree internal hemorrhoids. METHODS: One hundred patients were randomly divided into two groups and received PPH (n=42) and MMH (n=58) respectively. After two years, the efficacy, complications and function of defecation were compared. RESULTS: Two years after operation, the morbidities of hydrorrhea (2.38% vs 20.69%, P=0.007), dermal neoplasm formation (9.52% vs 25.86%, P=0.040) and narrowing in the caliber of the stools (2.38% vs 18.97%, P=0.027) were significantly lower in PPH group than those in MMH group (P<0.05). The morbidities of overall complication (9.52% vs 25.86%, P=0.040) and overall abnormal function of defecation (9.52% vs 29.31%, P=0.017) were lower in PPH group than those in MMH group (P<0.05). However, there were no significant differences of the morbidity of relapse (14.29% vs 10.34%, P=0.549), patient satisfactory degree (92.86% vs 87.93%, P=0.636) and overall symptom recurrence rate (19.05% vs 25.86%, P=0.424) between the two groups. CONCLUSIONS: Long-term efficacies of procedure for prolapse and hemorrhoids and Milligan-Morgan haemorrhoidectomy in the treatment of III and IV degree internal hemorrhoids are similar. PPH has better safety, less complications and less effect on abnormal function of defecation compared with MMH.


Asunto(s)
Hemorroides/cirugía , Membrana Mucosa/cirugía , Adolescente , Adulto , Anciano , Femenino , Hemorroides/patología , Humanos , Masculino , Persona de Mediana Edad , Prolapso , Suturas , Resultado del Tratamiento , Adulto Joven
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