Brodersengill2856

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Carbon sequestration peaked in June, while emission peaked in November. PAR was the dominant factor affecting daytime NEE (NEEd). VPD was the main factor that indirectly affected daytime NEEd, with an optimal VPD value that maximizes daytime NEE around 1-1.5 kPa. Soil temperature was the main factor affecting nighttime NEE (NEEn). SWC was a limiting factor for NEEn. Too high or too low SWC would inhibit NEEn, with an optimal SWC value of 0.28 m3·m-3.Helianthemum songaricum is a second-class protected plant in China, threatened by decreased population size and fragmentation of distribution area. It is a new record species in Ningxia. We analyzed population structure, spatial distribution, and relationship of different age classes of H. songaricum living in sandy and gravel habitats. The results showed that majority of H. songaricum individuals were belonged to age-class Ⅲ. The age structure of the population was inverted triangle. The population was at a declining stage. The spatial pattern and spatial association between different age class of H. songaricum were greatly affected by habitat condition, with strong dependence on spatial scale. Compared with sandy habitat, H. songaricum population in gravel habitat tended to be clustered distribution, with a more obvious positive correlation among different age classes. The difference between two habitats was related to environmental condition and plant community structure. H. songaricum from age-class Ⅰ and Ⅱ had mutually dependent ecological relationships.We analyzed the spatial heterogeneity of plant species diversity in shrub layers and its relationship with light environment in Quercus variabilis plantation and Q. variabilis-Platycladus orientali mixed forest, following the method of geostatistics. The results showed that plant species diversity indices (Shannon H, Simpson Ds, Margalef Ma) of shrub layers in Q. variabilis plantation were significantly lower than that in Q. variabilis-P. orientalis mixed forest. The variation ranges and spatial autocorrelation distances of plant species diversity index in Q. variabilis plantation were higher than that in Q. variabilis-P. orientalis mixed forest, with lower spatial homogeneity but stronger spatial dependence. The plant species diversity indices of H, Ds and Ma structural ratios of shrub layers in Q. variabilis pure forest were 44.2%-49.7%, with moderate spatial autocorrelation. The structure ratios of H, Ds and Ma in Q. variabilis-P. orientalis mixed forest were 1.5%-3.3%, with strong spatial autocorrelation. The spatial distribution of biodiversity showed obvious strip-like gradient trend in Q. variabilis plantation and patchy gradient change in Q. variabilis-P. orientalis mixed forest, suggesting that the spatial continuity of plant species of shrub layers was worse in Q. variabilis-P. orientalis mixed forest and that the spatial variation was stronger than that in Q. variabilis pure forest. Results of correlation analysis and stepwise regression analysis showed that the total light and plant canopy openness were the most significant factors affecting plant species diversity of shrub layers in both forest types. Light environment formed by plant canopy structure played a crucial part in maintaining plant diversity in shrub layer.We investigated soil CNP stoichiometry and nutrient dynamics of Cunninghamia lanceolata plantations at different stand ages (5, 8, 21, 27 and 40 years old) in Fujian Baisha Fores-try Farm. We measured the concentrations of soil total carbon (TC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), total calcium (Ca), total magnesium (Mg), and soil CNP stoichiometry at 0-10, 10-20, and 20-40 cm soil layers during different growth stages. The results showed that soil TC and TN concentrations and CN remained unchanged during stand development. Soil TP content showed an increase-decrease-increase trend with increasing stand ages. Soil TP content was lowest, whereas CP and NP were highest at the mature stage of C. lanceolate plantation in the 0-10 and 10-20 cm soil layers. However, soil TP content showed no significant differences in all stand ages at the 20-40 cm soil layer. The contents of Ca and Mg were lowest at the mature stage of C. lanceolata stand. The TC was positively correlated with soil CN, CP and NP. The TP was significantly and negatively correlated with soil CP and NP. Soil TP was a key factor regulating soil CP and NP stoichiometry. The development of mature plantation was mainly limited by soil P availability. To sustain the development of C. lanceolata plantations and improve nutrient cycling, phosphorus fertilizer could be applied during the rapid growth period of C. lanceolata. In addition, an appropriate extension of the rotation period of C. lanceolata plantation could facilitate soil nutrient restoration.Pertussis (whooping cough) is a vaccine-preventable bacterial infectious disease. Nevertheless, serious cases continue to be reported every year in the paediatric population. Pertussis poses a danger mainly to unimmunized or partially immunized infants under six months of age. It is still considered as a diagnostic challenge. The aim of this article is to present, through a clinical situation, the strategies for the prevention of pertussis and the correct management in case of suspicion of this disease. Through answers to questions we review the basics which every general practitioner should know.In connection with the scope and duration of the COVID-19 pandemic, the clinical judgement of clinicians and medical practitioners could be influenced such that diagnostic errors (delays and inaccuracies) may ensue. We hereby recall through two clinical scenarios the constant need for practitioners to take a step back in reflecting of the diagnostic process to avoid the « tunnel effect » which may result in delaying common and frequent infectious diseases. The flu-like symptoms presented by these patients (fever, myalgia and asthenia…) quickly prompted our emergency room colleagues to suspect SARS-CoV-2 infection. selleck screening library However, further investigations including imagery and blood cultures revealed completely different but common infectious disease conditions, which are potentially fatal.