孕前体质指数、孕期血红蛋白水平及孕期体重增长对妊娠结局的影响

目的探讨孕期血红蛋白水平、孕前体质指数及孕期体重增长对妊娠结局的影响。方法回顾性分析2021年8月至2021年12月云南省第三人民医院分娩产妇的病历资料。根据孕期血红蛋白水平分为低Hb组(孕晚期血红蛋白<110 g/L)、中Hb组(孕晚期血红蛋白水平为110~130 g/L)、高Hb组(孕晚期血红蛋白水平≥130 g/L);根据孕前体质指数分为3组:孕前BMI过低组(BMI<18.5 kg/m^(2))、孕前BMI正常组(BMI为18.5~24.9 kg/m^(2))、孕前BMI过高组(BMI≥25 kg/m^(2));根据妊娠期体重增加分为增重不足、增重正常、增重过度3组。对各组的妊娠结局进行比较。结果低Hb组、中Hb组、高Hb组的早产发生率,差异有统计学意义(P<0.05);孕前BMI过低组、孕前BMI正常组、孕前BMI过高组的新生儿出生体重、剖宫产、巨大儿、胎儿生长受限的发生率,差异有统计学意义(P<0.05);孕期增重不足组、孕期增重正常组、孕期增重过度组的新生儿体重、胎膜早破、巨大儿的发生率,差异有统计学意义(P<0.05)。结论孕期血红蛋白、孕前BMI及孕期体重增长均对妊娠结局产生影响,合理地对其进行控制,从而减少不良妊娠结局的发生,促进母婴健康。

Nitrous oxide emissions from three temperate forest types in the Qinling Mountains,China

To understand soil N2O fluxes from temperate forests in a climate-sensitive transitional zone,N2O emissions from three temperate forest types(Pinus tabulaeformis,PTT;Pinus armandii,PAT;and Quercus aliena var.acuteserrata,QAT)were monitored using the static closed-chamber method from June 2013 to May 2015 in the Huoditang Forest region of the Qinling Mountains,China.The results showed that these three forest types acted as N2O sources,releasing a mean combined level of 1.35±0.56 kg N2O ha^-1 a^-1,ranging from0.98±0.37 kg N2O ha^-1 a^-1 in PAT to 1.67±0.41 kg N2O ha^-1 a^-1 in QAT.N2O emission fluctuated seasonally,with highest levels during the summer for all three forest types.N2O flux had a significantly positive correlation with soil temperature at a depth of 5 cm or in the water-filled pore space,where the correlation was stronger for temperature than for the water-filled pore space.N2O flux was positively correlated with available soil nitrogen in QAT and PAT.Our results indicate that N2O flux is mainly controlled by soil temperature in the temperate forest in the Qinling Mountains.

植物功能性状对动态全球植被模型改进研究进展

动态全球植被模型(dynamic global vegetation models,DGVMs)在模拟和预测陆地生态系统对气候变化响应中表现出很大的不确定性,重要原因之一在于动态全球植被模型将定义植物功能型的性状值设置为常数,忽略了植物功能性状对环境变化的响应.动态全球植被模型现有的植物功能型框架已经严重地阻碍了其发展,因此迫切需要一种新的方法来克服这种局限性.植物功能性状不仅可以反映植物对环境连续变化的响应,而且与生态系统的结构和功能密切相关,可提升当前动态全球植被模型对生态系统过程的模拟和功能的预测.本文从动态全球植被模型发展和植物功能型局限性入手,详细介绍了植物功能性状发展现状及其对动态全球植被模型改进的重要价值,归纳总结了植物功能性状对动态全球植被模型改进的主要方法,并指明植物功能性状对动态全球植被模型改进的发展方向.以期通过凝练植物功能性状在构建下一代动态全球植被模型中发挥作用,推动动态全球植被模型在我国的发展和应用.

Qinghai-tibetan plateau peatland sustainable utilization under anthropogenic disturbances and climate change

Often referred to as the“Third Pole,”China’s Qinghai-Tibetan Plateau developed large amounts of peatland owing to its unique alpine environment.As a renewable resource,peat helps to regulate the climate as well as performing other important functions.However,in recent years,intensifying climate change and anthropogenic disturbances have resulted in peatland degradation and consequently made sustainable development of peatland more difficult.This review summarizes peatland ecological and economic functions,including carbon sequestration,biodiversity conservation,energy supplies,and ecotourism.It identifies climate change and anthropogenic disturbances as the two key factors attributing to peatland degradation and ecosystem carbon loss.Current problems in environmental degradation and future challenges in peatland management under the effects of global warming are also discussed and highlighted.

Consideration of climate change impacts will improve the efficiency of protected areas on the Qinghai-Tibet Plateau

The protection of migratory birds and their habitats is important to the ecological stability of the Qinghai-Tibet Plateau(QTP).Currently protected areas(PAs)were designed in accordance with species distribution patterns under current climatic conditions,thus ignoring climate change will lead to a decrease in the protection efficiency of PAs.In this study,using the flagship species Grus nigricollis,as an example,we used the maximum entropy(MaxEnt)model to simulate the distributions and conservation status of G.nigricollis and optimized the existing PA boundaries.The results showed that(1)suitable habitat-for G.nigricollis accounts for 12.48%of the QTP area,and the PAs established under current climatic conditions cover 17.84%of this suitable habitat area;(2)future climate changes will influence the distribution and quality of G.nigricollis habitats,and the average protection efficiency of the current PAs in four climatic scenarios will decrease from 17.84%to 15.31%;and(3)through optimization,the efficiency of existing PAs can be increased by 0.75 times and reach 28.37%,indicating PA planning must consider not only current climate conditions but also the effects of climate changes.Our results aim to address shortcomings in the conservation efficiency of PAs and provide an example for resolving mismatched PA boundaries and habitat changes for species.