Genotype‐by‐genotype specificity remains robust to average temperature variation in an aphid/endosymbiont/parasitoid system

Genotype‐by‐genotype interactions demonstrate the existence of variation upon which selection acts in host–parasite systems at respective resistance and infection loci. These interactions can potentially be modified by environmental factors, which would entail that different genotypes are selected under different environmental conditions. In the current study, we checked for a G × G × E interaction in the context of average temperature and the genotypes of asexual lines of the endoparasitoid wasp Lysiphlebus fabarum and isolates of Hamiltonella defensa, a protective secondary endosymbiont of the wasp's host, the black bean aphid Aphis fabae. We exposed genetically identical aphids harbouring different isolates of H. defensa to three asexual lines of the parasitoid and measured parasitism success under three different temperatures (15, 22 and 29 °C). Although there was clear evidence for increased susceptibility to parasitoids at the highest average temperature and a strong G × G interaction between the host's symbionts and the parasitoids, no modifying effect of temperature, that is, no significant G × G × E interaction, was detected. This robustness of the observed specificity suggests that the relative fitness of different parasitoid genotypes on hosts protected by particular symbionts remains uncomplicated by spatial or temporal variation in temperature, which should facilitate biological control strategies.     

城市污泥应用于边坡植被恢复对地表水环境的影响

将城市污泥应用于生态恢复因能避开粮食作物食物链而具有良好前景,但其对地表水环境影响仍不十分清楚.本文将城市污泥与建筑垃圾按1∶1体积比混合为生长基质,覆盖在模拟的煤矸石边坡上,播种8种乡土木本植物,对生长季植物生长情况以及坡面地表水和下渗水的电导率、p H、氮磷钾、重金属、多环芳烃等含量进行分析.结果表明:坡面植物生长良好,平均覆盖度达60%;地表水和下渗水的p H值近中性,变化不大,而电导率、氮磷钾、重金属和多环芳烃含量均较高,其中,氮、磷含量在整个生长季超过国家地表水环境质量Ⅴ类水质标准;7月重金属含量最高,其中,As含量只达地表水环境质量Ⅳ~Ⅴ类标准,其余重金属含量多达Ⅱ~Ⅳ标准;随着夏季雨水淋洗增加以及植物-土壤系统对化学物质的吸收、降解和固着作用,地表水和下渗水的电导率、氮磷钾、重金属和多环芳烃含量均显著下降,生长季后期重金属含量达到地表水环境质量Ⅱ~Ⅲ类标准,多环芳烃含量减少约一半.将城市污泥直接应用在煤矸石边坡生态恢复中有利于植物生长,植物-土壤系统使得生长基质中的有害物含量逐渐降低,对地表水环境的负影响主要表现为氮、磷的富营养化,但总体上其环境安全性可控.     

基于PAE编码系统构建的半自然条件下长江江豚行为谱

识别和编制动物行为谱是深入研究动物行为及其与环境复杂关系的基础和前提。本研究于2013年8月至2014年4月以栖息在铜陵淡水豚国家级自然保护区半自然水域的8头长江江豚为研究对象,采用焦点动物取样法和随机动物取样法观察记录了动物行为发生的过程、内容和环境,并以"姿势—动作—环境"(posture-act-environment,PAE)为轴心,以行为的功能为依据,构建了长江江豚的PAE行为谱。共分辨记录了半自然水域长江江豚的8种姿势、33种动作和46种行为,并定性描述了不同行为出现频率与年龄组、性别的关系。该行为谱综合了姿势和环境信息,有助于进一步研究长江江豚的生态与行为、促进长江江豚的保护。     

Infrastructure and the environment in the Anthropocene

For centuries, man‐made infrastructure has been viewed as separate from natural systems. Yet in the past few centuries, as the scale and scope of human activities have dramatically increased, there is accumulating evidence that natural systems are becoming increasingly, and in some cases entirely, managed by humans. The dichotomy between infrastructure and the environment is narrowing, and natural systems are increasingly becoming human design spaces. This is already apparent with the management of hydrologic systems for urban water supply, wildlife, agriculture, forests, and even the atmosphere, and we can expect management of the environment to become more so as human activities grow. Yet our infrastructure largely remains obdurate. They are designed to last for long times even as changes in the environment and technology accelerate. As such, our current infrastructure paradigms fail at the level of the complex, integrated systems and behaviors that characterize the Anthropogenic Earth. Infrastructure in the future will need to be designed for adaptive capacity and the complexities associated with techno‐environmental systems.     

北京城市与西北远郊地表臭氧浓度梯度移动监测研究

北京城市与区域臭氧浓度逐年升高,对自然生态系统已经构成影响。但地表臭氧在北京城市与远郊梯度空间上的连续递变特征机制尚不清楚。采用移动监测车,搭载臭氧分析仪,选择夏季典型臭氧污染天气,以北京教学植物园为对照点,从北京城市中心向西北远郊方向,多点位连续测定地表臭氧浓度。通过分析臭氧浓度和采样点周围归一化植被指数(NDVI)的关系以及典型臭氧污染情况下的天气形势和气团轨迹,探讨北京城市和区域臭氧浓度连续空间变化特征及机制。结果表明:(1)北京西北山区森林区域臭氧浓度显著高于"城市区域",约为城市区域的2.00倍。十三陵是地表臭氧浓度的分界点,从十三陵开始臭氧浓度陡然升高,在西北山区方向保持在高水平。空间上从高到低的顺序是西北山区(254.68μg/m~3)对照点教学植物园(220.89μg/m~3)城市支路(162.84μg/m~3)城市快速路和高速路(103.24μg/m~3);(2)植被分布影响臭氧空间格局。在相同时间范围内,臭氧浓度和NDVI正相关,随NDVI增加臭氧浓度呈Logistic增长;(3)西北山区地表臭氧空间变异系数为0.11,城市支路上平均为0.28,城市快速路上为0.26,高速公路上为0.36。山区地表臭氧浓度的空间变异系数最小,高速公路最大,城市快速路、城市支路空间变异较大;(4)大范围均压场、高压后部、低压前部等稳定型天气型易造成南向弱气流,能够把空气污染物输送到西北远郊,但本研究中监测到的西北山区高浓度臭氧并非当天从城区输送而来。北京城市与区域臭氧格局与植被的关系及成因需要深入研究。     

Mapping of quantitative trait loci controlling adaptive traits in coastal Douglas-fir. I. Timing of vegetative bud flush

Thirty three unique quantitative trait loci (QTLs) affecting the timing of spring bud flush have been identified in an intraspecific mapping population of coastal Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco var. menziesii]. Both terminal and lateral bud flush were measured over a 4-year period on clonal replicates at two test sites, allowing for the repeated estimation of QTLs. QTLs were detected on 12 linkage groups and, in general, each explained a small proportion of the total phenotypic variance and were additive in effect. Several QTLs influence the timing of bud flush over multiple years, supporting earlier evidence that the timing of bud flush through developmental stages is under moderate to strong genetic control by the same suite of genes through developmental stages. However, only a few QTLs controlling the timing of bud flush were detected at both test sites, suggesting that geographic location plays a major role in the phenology of spring growth. A small number of QTLs with year and site interactions were also estimated. Received: 20 July 2000 / Accepted: 19 October 2000     

Protected raspberry production alters aphid–plant interactions but not aphid population size

• 1 Aphid population dynamics in crops are often driven by interactions with their host plants, which can be extensively influenced by environmental change. Protective environments (i.e. plastic tunnels) are now frequently used for soft fruit production, which may affect the localized climate and alter such interactions. This two year study on red raspberry (Rubus idaeus) addressed how protected environments affected two aphid species; the large raspberry aphid Amphorophora idaei (LRA) and the small raspberry aphid Aphis idaei (SRA).
• 2 Temperatures were higher (up to 7–10 °C) in tunnels compared with the field. Plants in tunnels grew approximately 1.4 cm/week faster and had lower (approximately 35%) foliar amino acid concentrations than plants in the field.
• 3 Aphids affected plant growth differently depending on growing environment; they promoted plant growth by 18–37% in tunnels, although they had no such effect in the field. Aphids reduced total and essential amino acid concentrations, with SRA causing greatest reductions (approximately 40% and 33%, respectively).
• 4 Aphid population sizes were similar in both environments, although individual LRA were smaller in tunnels (30% smaller in 2007) compared with those in the field. We suggest that faster aphid development rates inside warmer tunnels were not realized as a result of the variable effects of the growing environment on amino acid composition.
• 5 We conclude that the increasing use of protected environments in crop production will not necessarily cause predictable increases in aphid populations, although it may alter aphid–plant interactions in terms of aphid‐induced changes to plant growth.

     

中国海洋渔业水域环境研究现状及展望

渔业水域环境是水生生物赖以生存、繁衍的最基本条件,优良的渔业水域环境是海洋渔业持续发展的物质载体与必然条件。近年来中国海洋渔业水域环境状况日趋严峻,依据海洋渔业水域监测数据,分析了中国海洋渔业水域环境的现状;概括了中国海洋渔业水域环境面临的主要问题及破坏原因;综述了海洋渔业水域环境保护及修复对策的研究现状,并对今后的研究工作提出了方向与内容上的展望。     

特定频谱波对水电导率影响的研究

目的:为了研究特定频谱波引起的水中离子浓度的变化以及电导率与频谱波间相互作用的规律,用特定频谱波对理化特性略有不同的纯净水、自来水、海水进行影响,研究其电导率的变化。方法:采用一元线性回归分析的方法对数据散点进行拟和,用方差分析来评价其拟合效果,以期发现其中的规律。结果:经过频谱波的影响各种水的电导率都有明显的提高,并且随着处理次数的增加,纯净水的电导率呈阶越式方式增加;自来水呈对数形式增加;而海水则表现为变化幅度微小。结论:造成这个现象的原因可能是由于水分子吸收了频谱波的能量,分子的平均动能增大造成的。这一过程使化学平衡(H2O)n≒xH2O (H2O)n-x和H2O≒ H OH-均向分解的方向运动,水中带电离子的浓度提高,因此电导率发生变化。而电导率提高方式的差异,则是水样在理化特性上的差异导致的。