RESUMO
Vegetation restoration can effectively improve the ecological environment of mining areas, enhance the ecological service function, and promote the carbon sequestration and sink increase in the ecosystem. The soil carbon cycle plays an important role in the biogeochemical cycle. The abundance of functional genes can predict the material cycling potential and metabolic characteristics of soil microorganisms. Previous studies on functional microorganisms have mainly focused on large ecosystems such as farmland, forest, and wetland, but relatively little attention has been paid to complex ecosystems with great anthropogenic interference and special functions, such as mines. Clarifying the succession and driving mechanism of functional microorganisms in reclaimed soil under the guidance of vegetation restoration is helpful to fully explore how functional microorganisms change with the change in abiotic and biotic conditions. Therefore, 25 topsoil samples were collected from grassland (GL), brushland (BL), coniferous forests (CF), broadleaf forests (BF), and mixed coniferous and broadleaf forests (MF) in the reclamation area of the Heidaigou open pit waste dump on the Loess Plateau. The absolute abundance of soil carbon cycle functional genes was determined using real-time fluorescence quantitative PCR to explore the effect of vegetation restoration on the abundance of carbon cycle-related functional genes in soil and its internal mechanism. The results showed that:â the effects of different vegetation restoration types on the chemical properties of reclaimed soil and the abundance of functional genes related to the carbon cycle were significantly different (P<0.05). GL and BL showed significantly better accumulation of soil organic carbon, total nitrogen, and nitrate nitrogen (P<0.05) than that in CF. â¡ The gene abundance of rbcL, acsA, and mct was the highest among all carbon fixation genes. The abundance of functional genes related to carbon cycle in BF soil was higher than that in other types, which was closely related to the high activity of ammonium nitrogen and BG enzymes and the low activity of readily oxidized organic carbon and urease in BF soil. The functional gene abundance of carbon degradation and methane metabolism was positively correlated with ammonium nitrogen and BG enzyme activity and negatively correlated with organic carbon, total nitrogen, readily oxidized organic carbon, nitrate nitrogen, and urease activity (P<0.05). ⢠Different vegetation types could directly affect soil BG enzyme activity or affect soil nitrate nitrogen content, thus indirectly affecting BG enzyme activity, in turn manipulating the abundance of functional genes related to the carbon cycle. This study is helpful to understand the effects of different vegetation restoration types on the functional genes related to the carbon cycle in the soil of mining areas on the Loess Plateau and provides a scientific basis for ecological restoration and ecological carbon sequestration and sink enhancement in mining areas.
Assuntos
Ecossistema , Solo , Carbono , Nitratos , Urease , Ciclo do Carbono , Florestas , NitrogênioRESUMO
OBJECTIVE: To understand the infection status of soil-transmitted nematodes in Xinchang County, so as to offer the evidence for the formulation of control measures. METHODS: The infection of soiltransmitted nematodes in residents was investigated by using the Kato-Katz method and cellophane anal swab. RESULTS: A total of 3 069 people were examined in 2009, 2012 and 2017, of which 1 520 people were male and 61 people were infected, with the infection rate of 4.01%; 1 549 were women and 54 people were infected, with the infection rate of 3.48%. The infection rates of soil-transmitted nematodes in 2009, 2012 and 2017 were 4.60%, 4.29% and 2.35%, respectively, and the total infection rates were decreased (χ2 = 7.151, P < 0.05). CONCLUSIONS: The rate of soil-transmitted nematode infection in Xinchang County is declining, and it is at a low epidemic level.
Assuntos
Nematoides , Infecções por Nematoides , Solo , Animais , China/epidemiologia , Feminino , Humanos , Masculino , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/prevenção & controle , Vigilância da População , Prevalência , Solo/parasitologiaRESUMO
OBJECTIVE: To investigate the relationship between the second to the fourth digit ratio (2D:4D) and body mass index (BMI) in infertile men of the Han ethnic group in Ningxia. METHODS: Using anthropometry, we calculated the mean ratio of 2D:4D and BMI of 197 infertile men and 148 normal healthy male controls, followed by analysis of their relationship. RESULTS: The BMI was correlated positively with the 2D:4D ratio of the left hand in the infertile men (P < 0.05) and in the patients with a higher 2D:4D ratio of the left hand (P < 0.05), but negatively with the 2D:4D ratio of the righ/left (Dr-1) (left: P < 0.01; Dr-l: P < 0.05). The mean 2D: 4D ratio and BMI were both lower in the normal control than in the infertile men, with statistically significant differences in BMI (P < 0.05) and the 2D:4D ratio of the left hand (P < 0.05). CONCLUSION: There is a correlation between the 2D:4D ratio and BMI in infertile men.
Assuntos
Índice de Massa Corporal , Dedos/anatomia & histologia , Infertilidade Masculina/diagnóstico , Estudos de Casos e Controles , Humanos , MasculinoRESUMO
Polysaccharopeptides (PSPs) from Coriolus versicolor have been used as immunomodulatory and anticancer agents. However, most studies have concentrated on the mycelial PSPs and not those in the fermented broth. On the other hand, Lycium barbarum fruit has been used as a traditional Chinese herbal medicine for two millennia. Its extract contains various nutrients, minerals, and also polysaccharide-protein complexes, which are proven to be bioactive. Herein we report the effects of L. barbarum fruit extract on the mycelial growth and extracellular PSP (ePSP) production of C. versicolor LH1 by using a submerged fermentation process in 20l fermenters. Fermentation production of C. versicolor biomass and its ePSP were augmented in the presence of L. barbarum extract. The ePSP such obtained differs from those obtained with normal culture medium in terms of simple sugar composition and protein content but shows similar overall chemical structures as analyzed by Fourier transformed infrared spectroscopy. Moreover, the ePSP from C. versicolor cultured with supplementary L. barbarum extract exhibits significant immunomodulatory activity as judged by its effects on the production of nitric oxide and several cytokines by murine RAW264.7 macrophages.