Development of a hydrothermal time seed germination model which uses the Weibull distribution to describe base water potential

Seed germination has been modelled extensively using hydrothermal time (HTT) models, that predict time to germination as a function of the extent to which seedbed temperature, T, and water potential, Ψ, exceed the base temperature, T_b, and base water potential, Ψ_b, of each seed percentile, g. Within a seed population the variation in time to germination arises from variation in Ψ_b(g) modelled by a normal distribution. We tested the assumption of normality in the distribution of Ψ_b(g) by germinating seed of two unrelated species with non-dormant seed (Buddleja davidii (Franch.) and Pinus radiata D. Don) across a range of constant Ψ at sub-optimal T. When incorporated into a HTT model the Weibull distribution more accurately described both the right skewed distribution of Ψ_b(g) and germination time course over sub-optimal T than the HTT based on the normal distribution, for both species. Given the flexibility of the Weibull distribution this model not only provides a useful method for predicting germination but also a means of determining the distribution of Ψ_b(g).     

Sugar receptor response of the food-canal taste sensilla in a nectar-feeding swallowtail butterfly, Papilio xuthus

The feeding behavior in nectar-feeding insects is triggered by a sugar-receptor response in contact chemosensilla. The contact chemosensilla are distributed not only on tarsi and the outside of the proboscis but also on the inside of the food canal in Lepidoptera. Although the chemosensilla inside the food canal are assumed to detect sweet taste during the passage of nectar through the food canal, their electrophysiological function has received little attention. In the nectar-feeding Asian swallowtail butterfly, Papilio xuthus (Lepidoptera: Papilionidae), we found 15- to 30-μm-long sensilla neatly lined up along the inside galea wall, which forms the food canal in the proboscis. The receptor neurons of these sensilla responded to sucrose. We hypothesized that starch and sucrose compete with each other for a taste receptor site on the sensilla. When we added starch and sucrose to the food-canal sensilla, the electrophysiological responses of food-canal sensilla were inhibited in parallel with the food-sucking behavior of the butterflies. These results suggest that the food-canal sensilla are involved in the behavioral control of nectar-sucking in this butterfly species.     

森林、茶园和菜园3种土地利用类型下的蝴蝶群落物种与功能多样性比较研究

土地利用变化是蝴蝶多样性丧失的重要原因,为探究森林转变为茶园与菜园后蝴蝶多样性的变化特点,于2019年4—10月采用样线法在江苏宝华山逐月调查了上述3种土地利用类型下的蝴蝶多样性。调查结果显示,共监测到蝴蝶5科47属62种;森林的Shannon Wiener多样性指数、Margalef丰富度指数和Pielou均匀度指数均高于茶园和菜园,但Simpson优势度指数茶园最高;功能丰富度指数（F_ric）、二次熵指数（RaoQ）都是森林显著高于其他2种土地利用类型,但菜园的F_ric显著高于茶园;功能离散度指数（F_div）和功能均匀度指数（F_eve）3种土地利用类型间无显著差异。蝴蝶群落物种和功能多样性与植被类型及其时空变化有明显的相关性,土地利用变化等人类活动对蝶类群落多样性有破坏作用。     

“An eye for an eye?”—on the generality of the intimidating quality of eyespots in a butterfly and a hawkmoth

Large eyespots on the wings of butterflies and moths have been ascribed generally intimidating qualities by creating a frightening image of a bird or mammal much larger than the insect bearing the eyespots. However, evidence for this anti-predator adaptation has been largely anecdotal and only recently were peacock butterflies, Inachis io, shown to effectively thwart attacks from blue tits, Parus caeruleus. Here, we test whether large eyespots on lepidopterans are generally effective in preventing attacks from small passerines and whether the size of insect or bird can influence the outcome of interactions. We staged experiments between the larger eyed hawkmoths, Smerinthus ocellatus, and the smaller peacock butterflies, I. io, and the larger great tits, Parus major, and the smaller blue tits, P. caeruleus. Survival differed substantially between the insect species with 21 of 24 peacock butterflies, but only 6 of 27 eyed hawkmoths, surviving attacks from the birds. Thus, surprisingly, the smaller prey survived to a higher extent, suggesting that factors other than insect size may be important. However, great tits were less easily intimidated by the insects’ eyespots and deimatic behaviour and consumed 16 of 26, but the blue tits only 8 of 25, of the butterflies and hawkmoths. Our results demonstrate that eyespots per se do not guarantee survival and that these two insects bearing equally large eyespots are not equally well protected against predation.     

Pollinator insects benefit from rotational fallows

The importance of rotational fallows for pollinating insects in intensively cultivated farmland was studied in a three-year field experiment. The focus was on the establishment method (undersowing or seed mixture sown post-tillage), seed mixture (competitive Festuca pratensis-Phleum pratense-Trifolium pratense or less competitive Agrostis capillaris-Festuca ovina mixture) and duration (1 or 2 years) of the fallow. The seed mixture and duration affected the pollinators more than the method of establishment. Pollinator species richness was higher in fallows sown with less competitive than with competitive grasses and it increased in the second year. Stubble fields reached as high pollinator species richness already during the first year as fallows with less competitive grasses did in the second year. Pollinator abundance was highest in those treatments in which species richness of flowering plants was highest. The results suggest that the benefits of rotational fallows for pollinators increase when they are established as stubble or using seeds of less competitive grasses and when the field is fallowed for (at least) two summers.     

Tensions of Praxis: A New Taxonomy for Social Movements

This essay introduces and illustrates tensions of praxis that humans involved in activism face so that thought–action translation can occur more reflexively. Because social movements face unique challenges in effecting social change (Simons, 1970; Stewart, Smith, & Denton, 2007) the tensions of praxis are especially important for this type of social change agency. Therefore, this essay situates itself within discussions of environmental social movements and begins with a brief introduction of praxis as a theoretical and practical concern. Then, in order to illuminate the tensions of praxis, the following tensions are identified, explained, and illustrated: (1) this world or that world; (2) activity or inactivity; and (3) means and ends. Throughout the essay, primary data from a 2009 interview with Julia Butterfly Hill are used to illustrate these tensions. The essay concludes with theoretical and practical significance of the tensions of praxis and suggests directions for future research.     

石油开采、炼制及储存过程中含油污泥的综合处理

主要介绍石油开采、炼制、储存过程中产生的石油油泥的处理和回收利用。油泥经化学水洗调质处理后，通过特殊的分离沉降罐与卧式离心机和碟式离心机分别配合使用达到降低分离难度，提高工艺适应性和获得良好的油、水、泥分离效果。     

安徽省重大旱灾对称性特征及其趋势判断

基于安徽省14个气象站点1961~2013年逐月降水数据,采用克里金空间插值法、经验正交函数分解法(EOF)和降水距平百分率对安徽省降水的时空变化特征进行分析,并对安徽省旱灾的发生趋势进行判断。结果表明:(1)近53年安徽省年降水量呈上升趋势,但目前处于下降趋势;(2)在空间上降水量自南向北逐渐减小,根据EOF分析,安徽省降水的空间分布表现为长江流域与淮河流域之间降水反向变化的特征,淮河以北地区与其余地区降水反向变化的特征,皖西大别山区和安徽北部降水偏多,其余地区降水偏少的特征;(3)安徽省的重大干旱符合可公度特征并存在时间对称性规律,计算得出2016年左右安徽省可能发生严重干旱,随机概率为61.1%。该研究对安徽省未来农业及经济的稳健发展具有重要意义。     

Linear features and butterflies: the importance of green lanes

Green lanes are unmetalled tracks between fields of variable width, which may be sunk below or raised above field level, and bounded on both sides by ‘grass’ banks, hedgerows or dry-stone walls. In the UK they have no unique planning status and have been overlooked as discrete landscape elements. Green lanes were surveyed for butterflies in 1997 on lowland arable farmland on the Trafford/north Cheshire border (Warburton) and on upland grassland in the Yorkshire Dales (Ribble Valley). At the lowland site the green lanes were bounded by vegetation and were compared with grass banks and single hedgerow field boundaries; at the upland farm, the green lanes were bounded by dry-stone walls and were compared with grass banks and single dry-stone walls. Data from earlier work on a largely arable farm (Manydown) in Hampshire in 1987 and 1988 were re-analysed to make comparisons between a green lane, the rides and glades of two coppiced woodlands, and the grass banks and single hedgerows surrounding arable fields. Green lanes, whether bounded by vegetation or stone were superior to other common farmland biotopes with the exception of woodland, in terms of both butterfly abundance and species richness.Multiple regression of the Warburton data indicated the importance of green lanes, adjacent habitat type, and nectar sources for species richness and butterfly abundance. The interior of green lanes had lower windspeeds, and more bramble nectar sources than hedgerows or grass banks. By their nature they occupy a larger area of uncropped land, and are subject to a reduced disturbance regime and reduced inputs of agrochemicals and fertilisers. Their value as biodiversity reservoirs in intensively managed land is likely to be high.     

Using citizen science butterfly counts to predict species population trends

Citizen scientists are increasingly engaged in gathering biodiversity information, but trade‐offs are often required between public engagement goals and reliable data collection. We compared population estimates for 18 widespread butterfly species derived from the first 4 years (2011–2014) of a short‐duration citizen science project (Big Butterfly Count [BBC]) with those from long‐running, standardized monitoring data collected by experienced observers (U.K. Butterfly Monitoring Scheme [UKBMS]). BBC data are gathered during an annual 3‐week period, whereas UKBMS sampling takes place over 6 months each year. An initial comparison with UKBMS data restricted to the 3‐week BBC period revealed that species population changes were significantly correlated between the 2 sources. The short‐duration sampling season rendered BBC counts susceptible to bias caused by interannual phenological variation in the timing of species’ flight periods. The BBC counts were positively related to butterfly phenology and sampling effort. Annual estimates of species abundance and population trends predicted from models including BBC data and weather covariates as a proxy for phenology correlated significantly with those derived from UKBMS data. Overall, citizen science data obtained using a simple sampling protocol produced comparable estimates of butterfly species abundance to data collected through standardized monitoring methods. Although caution is urged in extrapolating from this U.K. study of a small number of common, conspicuous insects, we found that mass‐participation citizen science can simultaneously contribute to public engagement and biodiversity monitoring. Mass‐participation citizen science is not an adequate replacement for standardized biodiversity monitoring but may extend and complement it (e.g., through sampling different land‐use types), as well as serving to reconnect an increasingly urban human population with nature.