A new sampler for extracting undisturbed surface peat cores for growth pot experiments

The sampler extracts uncompressed cores of 13·3 cm in diameter, up to 70 cm long, from the surface layers of peat. It has two close-fitting concentric cylindrical tubes, the outer one acting as a cutter and the inner one as a collector. As the outer tube is introduced by rotation into the peat, the cut core is collected in the inner tube which is maintained in a fixed position during the rotation phase and then pushed down stepwise. This limits friction between the peat core and the wall of the corer and prevents compression or distortion of the peat. These problems are also reduced by means of three skew cutters allowing the peat to be supported during the slicing action. Air can penetrate between the tubes to the lower end of the core, suppressing any suction effect during withdrawal. The sampler has been tested and has worked satisfactorily in many different peat types.     

Different mechanisms explain feeding type-specific patterns of latitudinal variation in herbivore damage among diverse feeding types of herbivorous insects

To determine whether latitudinal variation in herbivore impact exists, we examined three major herbivorous insect feeding types (chewers, gallers, and miners) on/in leaves of Japanese beech. Herbivores were collected with litter traps deployed in forests across a latitudinal gradient of 10°. Leaf litter analyses demonstrated that chewing herbivory increased with increasing latitude of collection site. However, the densities of miners and gallers decreased with latitude. To test whether latitudinal variation in herbivore damage occurs in the absence of geographically differentiated environmental cueing (e.g., physical stresses or herbivore damage), we measured both genetically determined constitutive leaf traits and herbivore damage in a common-garden experiment. In this experiment, miner density decreased with latitude, but chewing herbivory did not vary latitudinally. Galler density was higher on trees from native provenances than on trees from unrelated provenances likely because of local adaptations. Leaf mass per unit area (LMA), tannin, and phenolics all decreased with latitude of provenance. The latitudinal variation in one constitutive leaf trait (LMA) best explained latitudinal variation in chewing herbivory. Thus, different mechanisms account for feeding type-specific patterns of latitudinal variation in herbivore damage among different herbivore feeding types.     

Goodness of Fit of Discriminant Functions from the Vector Space of Fixed Variates

Alternative proofs of some of KSHIRSAGAR's (1971) results on testing discriminant functions or canonical variables in the vector space of fixed variates are given. These results are derived in terms of the original variates unlike KSHIRSAGAR (1971) who derives the results by using random orthogonal transformations and triangular decompositions of the original matrix variates.     

脆木耳生物学特性及驯化栽培

对采自海南省白沙县鹦哥岭阔叶树腐木上的标本,根据形态学特征和多基因分析,鉴定为脆木耳Auricularia fibrillifera,经分离纯化获得纯菌株作为实验材料,为了充分利用和开发木耳属资源,首次对该种的生物学特性和驯化栽培进行了研究。研究不同碳源、氮源、无机盐和生长因子在固体培养条件下对脆木耳菌丝生长的影响,对以上4个因素进行单因素试验,从中选出3个最优的水平进行正交试验。结果表明：脆木耳菌丝最适生长温度为33℃,最佳碳源为麦芽糖,最佳氮源为牛肉粉,最佳无机盐添加量为1.5% PO₄^3--1% Mg²⁺,最佳生长因子为玉米汁。驯化栽培过程中,栽培配方为：木屑78%,麸皮20%,石膏粉1%,石灰粉1%,发菌温度为22℃可使脆木耳菌丝在40d左右满袋,且生长旺盛,可培育出子实体。     

苏州文人园林曲桥路径对视线引导的实验研究

选取3处苏州园林的曲桥路径,现场邀请游人取景拍照,获取其游园过程中关注景物、视线方向等信息,结合路径与景物关系,通过实验方法分析曲桥路径中游人赏景的视觉行为特征。通过定量分析发现,苏州文人园林中曲桥转折间带来的空间位置变化影响着人们的视觉行为,其中景物视距与方向对人们的观景兴致存在显著影响,视距在3~33 m时,游人观景兴致最佳;同时路径方向与观景方向的垂直关系、路径对景物的指向关系可增强游人对相应景观的观赏兴致,曲桥中对垂直与指向关系的运用存在一定的规律。     

正交-满意度函数优化灵芝多糖及三萜共提取条件及其清除自由基活性

灵芝Ganoderma lingzhi是我国的一种著名珍稀药用真菌,多糖及三萜类化合物是其主要活性成分提。取乙时醇间水4h溶和液料为液提比取1:剂40,,以多灵糖芝和多三糖萜及的三提萜取提率取分率别为达响到应1值.13,=%正?和交k0-.4满6意%。度优函化数条优件化下乙提醇取含的量多、糖提和取三温萜,前者DPPH自由基清除活性高于热水法提取多糖,后者与乙醇浸提法提取三萜有相近的DPPH自由基清除活性。     

The response of cerambycid beetles (Coleoptera: Cerambycidae) to long‐term fire frequency regimes in subtropical eucalypt forest

Fire has a varied influence on plant and animal species through direct (e.g. fire‐induced mortality) and indirect (e.g. modification of habitat) effects. Our understanding of the influence of fire regime on invertebrates and their response to fire‐induced modifications to habitat is poor. We aimed to determine the response of a beetle family (Coleoptera: Cerambycidae) to varying fire treatments and hypothesised that the abundance of cerambycid beetles is influenced by fire frequency due to modifications in habitat associated with the fire treatments. Arthropods were sampled across 3 months in annually and triennially burnt areas (treatments starting in 1952 and 1973 respectively), an area unburnt since 1946, and a former unburnt treatment, burnt by wildfire in 2006. Eleven different cerambycid taxa were collected using flight intercept panel traps, dominated by three species (Ipomoria tillides, Adrium sp. and Bethelium signiferum) which made up 99% of individuals collected. Over the sampling period the long unburnt treatment had significantly lower species richness than the triennial and wildfire treatments. Cerambycid abundance was significantly higher in the triennially burnt treatment than in all other fire treatments. Ipomoria tillides was more abundant in both frequently burnt treatments, Adrium sp. was more common in triennially burnt areas, whereas B. signiferum, was more common in the wildfire affected treatment. Some, but not all, cerambycid beetles were more common in areas with a more open understorey (i.e. resulting from frequent burning), and lower tree basal area, as this likely influences their ability to fly easily between food sources. Cerambycid abundance was positively related to the volume of coarse woody debris and healthy tree crowns. Cerambycid beetles were clearly influenced by historic fire regime, suggesting that changes in fire regime can potentially have a profound influence on arthropod assemblages, and subsequent influences on ecosystem processes, which are currently poorly understood.     

Chelate-assisted phytoextraction of lead using Fagopyrum esculentum: laboratory vs. field experiments

Abstract

The development of more sustainable remediation techniques has been receiving greater attention, as an alternative to soil excavation plan in urban gardens. An in situ phytoextraction experiment with buckwheat (Fagopyrum esculentum) was performed with a 5?mmol kg^?1 citric acid (CA) application. Joint experiments under laboratory conditions were conducted using various cultivars of F. esculentum in two soils with a Pb contamination of either geogenic or anthropogenic origin and various chelate concentrations. Results show that a minimum dose of 50?mmol kg^?1 of CA is required to lower soil pH and raise the concentration of mobile Pb–CaCl₂ for both soils. Consequently, Pb shoot uptake is increased from 6.3 to 8.9 times depending on soil type. Phytoextraction efficiency is found to be 1.3 to 2.0 times higher in the anthropogenic contaminated soil than in the soil with geogenic Pb. A scale effect has also been identified since Pb root accumulation under laboratory conditions was 2.4 times higher than in the field experiment. Despite an increase in the Pb extraction rate with CA, buckwheat appears to lack the efficiency needed to remove Pb in moderately contaminated soils. The calculated remediation period would last 166?years to remove the mobile Pb fraction.     

Egg-Cracking Vibration as a Cue for Stink Bug Siblings to Synchronize Hatching

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协同分布式实验2.0 (CDE 2.0):生态学野外研究新方法

全球野外实验网络是近年来兴起的生态学实验方法,产生了“协同分布式实验”(CDE)、“分布式协作实验”(DCE)的野外实验网络和英国生物学记录中心(BRC)的野外观察网络等具体方法,但均存在尺度小、周期短或数据偏差问题.野外实验网络的协议设计应秉持实验优于观察测量、数据数量优于数据质量和尺度优于操作的原则.综合上述方法,本研究提出利用公众科学(citizen science)获得大范围、多尺度和长周期的数据,采用环境因子作为协变量对公众参与者的实验数据集进行验证后,将其作为后验概率与作为主观概率的生态学家实验数据集进行比对,以完成数据有效性验证,克服公众参与者数据质量瑕疵,并提出了相应的统计学模型.讨论了生态学实验数据中应用先验概率、先验与后验概率的逻辑关系以及后验概率发现演化过程新关系的可能性.这种方法更符合统计学采样规范,并增加了大尺度时空的样本量.该方法有望为生态学研究所寻找的一般性理论提供方法支持,新方法可称之为“协同分布式实验2.0”(CDE 2.0).