Study on Sterilization Method of Endophytic Fungi in Tall Fescue(Festuca arundinacea)and Ryegrass(Lolium perenne)Seeds

[Objectives]This study was conducted to obtain the best solution for sterilizing tall fescue(Festuca arundinacea)and ryegrass(Lolium perenne)seeds by heating in a water bath for a short time.[Methods]The tall fescue and ryegrass seeds infected with endophytic fungi were sterilized by heating in a water bath to compare seed germination and initial growth of turfgrass seedlings under different treatment time.[Results]Sterilization in a 60℃water bath for 20 and 30 min both inhibited the germination of tall fescue and ryegrass seeds,while the 20 min treatment did not significantly affect the lengths of stems,leaves and roots of seedlings.The 20 min water bath sterilization treatment had no effects on the plant heights and biomass of the two turfgrass seedlings and the tiller number of ryegrass,but sterilization for 30 min significantly reduced the aboveground and total biomass of seedlings and the tiller number of ryegrass.[Conclusions]Sterilization in a water bath at 60℃ for 20 min achieved rapid sterilization in a short time,without significantly negatively affecting the growth of seedlings.

Preliminary Study on Dynamic Changes of Insect Communities in Airport Ground Cover Areas in Different Weather Conditions

[Objectives]This study was conducted to investigate insect activity rhythms in airport ground cover areas,and provide guidance for insect control and bird strike prevention.[Methods]The daily rhythm of insects in the northern area of the airport was studied,and their activity rhythms and characteristics under different weather conditions were analyzed.[Results]In rainy days,the insect number in the three sample areas was low.In cloudy days,insect activity was relatively stable,and insect number was consistent in the morning and evening,and maintained in a stable range,while in sunny weather,insect activity was increased,and the number changed greatly with time.For a single tussock plant growth area,the number of insects was at a relatively low level under rainy weather.In fine weather,the peak period of insect activity was between 10:00-11:00 and 14:00-15:00.[Conclusions]This study can provide a reference for the formulation of safe flight departure time.

Comparative Study on the Effects of Three Carbon Nanomaterials on the Growth of Festuca arundinacea in Compost Substrate

[Objectives] This study was conducted to provide a scientific basis for the utilization of municipal solid waste resources, the remediation of contaminated substrates and the ecological safety of urban lawn planting. [Methods] Graphene, multi-layer graphene oxide and multi-walled carbon nanotubes were added to municipal solid waste(MSW) compost as turf substrate to determine the morphological indicators such as turfgrass biomass, chlorophyll contents and plant height. [Results] There were no significant differences in the plant height of Festuca arundinacea between different treatment groups in the first 30 d. The effects of adding different carbon nanomaterials on the fresh and dry weights of F. arundinacea were not significantly different. The aboveground biomass of F. arundinacea was the largest after adding graphene oxide, and the underground fresh weight decreased significantly in the hydroxyl multi-walled carbon nanotube treatment compared with the control. As to the chlorophyll content, the graphene oxide treatment was the highest, but there were no significant differences between all the treatment groups and the control group. [Conclusions] This study can provide data support for MSW compost substrate, lawn planting system and heavy metal pollutant passivating agents.

基于红外相机技术的天津城市地栖哺乳动物昼夜活动节律评价

城市化进程可导致自然栖息地大量丧失和破碎化,继而影响野生动物的活动节律和生态位关系。因此对各物种活动节律和生态位关系的精准评价是理解城市生物多样性维持机制的关键基础。为探究地栖哺乳动物昼夜活动节律以及物种之间的时间生态位关系,作者于2019年11月至2021年11月在天津城镇区域架设60台红外相机进行调查。本研究从平均活动时间、聚集度、方差、活跃度水平和活动属性等角度评价了狗(Canis lupus)、猫(Felis catus)、黄鼬(Mustela sibirica)、东北刺猬(Erinaceus europaeus)、蒙古兔(Lepus tolai)和亚洲狗獾(Meles leucurus)等物种的昼夜活动特征,同时使用核密度分析评价了物种的时间生态位重叠程度,并利用广义加性模型探究城市化水平对时间生态位重叠系数的影响趋势。本研究共获得有效相机监测天数11,517天,监测到地栖哺乳动物独立事件数2,428个。结果表明,狗表现出偏昼行性活动特征;黄鼬、东北刺猬和亚洲狗獾表现出夜行性或偏夜行性活动特征,猫和蒙古兔则为间歇性活动。蒙古兔表现出最高的活跃度水平(0.68,95%CI:0.56–0.73),亚洲狗獾的活跃度水平最低(0.40,95%CI:0.29–0.44)。80%的物种对表现出高度的时间生态位重叠,但物种在昼夜活动的时间分配上均存在显著差异。猫-黄鼬表现出最高的时间生态位重叠程度(Δ=0.88,95%CI:0.82–0.93),狗-东北刺猬的时间生态位重叠程度最低(Δ=0.35,95%CI:0.31–0.40)。猫-东北刺猬、东北刺猬-蒙古兔的时间生态位重叠系数与城市化水平呈现线性正相关关系,狗-东北刺猬的时间生态位重叠系数随城市化水平增加表现出先上升后下降的非线性趋势。本研究首次对天津城镇区域地栖哺乳动物的昼夜活动节律进行了系统性分析,研究结果表明各物种昼夜活动节律存在较高的异质性,同时揭示了物种时间生态位关系对城市化水平具有多响应模式。本研究有助于解析我国城镇景观野生动物的区域共存机制,同时可以为城市野生动物的保护和管理提供基础性参考。

Competitive interactions and coexistence of sympatric flagship carnivores in Asia

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore declines.Although studies exploring the dynamics and competition between tigers(Panthera tigris)and leopards(P.pardus)span decades,there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative and interference competition.We gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and leopards.Elevation and ungulate density were the most important predictors in regulating the coexistence mechanisms.Tigers and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial niche.In addition,they showed a higher dietary overlap in the prey-rich regions.We determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation structures.Meanwhile,studies with multiple metrics would promote the detection of interference competition.Our study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad scale.Policy-makers and managers should pay more attention to the factors of elevation,prey abundance,and habitat structures for the conservation of tigers and leopards.

陆生食肉动物竞争与共存研究概述

陆生食肉动物(食肉目哺乳动物,以下简称食肉动物)作为食物链与营养级的高位物种对维持生态系统结构与功能稳定性起到重要作用。过度人类干扰已在全球范围内造成食肉动物种群数量剧烈下降和栖息地质量显著退化,探究食肉动物的区域共存机制对理解生物群落构建、濒危物种保护与管理具有重要意义。本文通过梳理100余篇有关食肉动物在空间、时间和营养3个生态位维度上相互作用的研究,分析了体型大小、猎物组成、种群结构、环境差异、人类干扰和气候变化等因素对食肉动物种间关系和区域共存的影响,并对今后食肉动物区域共存研究中亟需解决的问题进行了展望。食肉动物通过生态位分离达到共存并没有单一的理论解释,猎物、栖息地和人类干扰等因素可以调节食肉动物相互作用关系并直接或间接地影响共存,共同适应在食肉动物区域共存中具重要作用。食肉动物区域共存是经过长期演化形成的相对稳定状态,需要以动态的眼光去审视。要明晰生态位重叠与区域共存机制的区别与联系,在理解生态位分离的基础上,结合生活史、家域和行为等对食肉动物共存进行综合分析。