植物诱导防御对昆虫种群结构的影响研究

植物通过自身的诱导防御可以影响昆虫的寄主选择、生长发育,以及捕食性天敌和寄生性天敌对昆虫的追踪与确认。本文总结和回顾植物诱导防御对昆虫种群结构的影响,并对发展前景进行了简单论述。还强调了要从环境、物种相互作用关系以及生态结构的演替过程,总体方向上对植物诱导抗虫性进行全面系统分析,才能更深刻地理解这一理论。     

Avoiding negativity bias: Towards a positive psychology of human–wildlife relationships

Recently, new approaches to wildlife management are being developed, such as coexistence management and convivial conservation. These approaches aim to shift management practices from mitigating human–wildlife conflicts towards cohabitation and explore mutual benefits. To align empirical research to these new approaches, we argue for the relevance of positive psychology theory to inspire and structure research into the benefits of human–wildlife interactions. Positive psychology suggests three pathways through which human–wildlife interactions may lead to happiness and well-being: pleasure, engagement, and meaning. Applying these pathways to human–wildlife research may (i) structure existing research into the benefits of human–wildlife interactions, (ii) disclose unidentified benefits of human–wildlife interactions, and (iii) unravel mechanisms which make experiencing and protecting wildlife worthwhile and rewarding. Also, we suggest a potential feedback loop between wildlife experiences, happiness and well-being, and pro-environmental behaviours. More in-depth research into these mechanisms may improve our understanding of attitudes towards conservation of wildlife and its habitat and may suggest strategies to strengthen stewardship actions and public support for conservation strategies. Together, these strands of research could initiate research into what could be called a “Positive Ecology”.     

The Effect of Ambient Temperature on Intraspecific Interactions Controlling Heat Tolerance in the Oligochaetes Enchytraeus albidus and Tubifex tubifex

A signal (nonlethal) increase in ambient temperature (to 26 and 31°C for the oligochaetes Enchytraeus albidus and Tubifex tubifex, respectively) induces intraspecific interactions mediated by the release of pheromones into the medium. The pheromones cause physiological changes that persist after the cessation of either these interactions or pheromone action and are expressed as a considerable increase in the heat tolerance of individual E. albidus and T. tubifex.     

Emigration mechanisms in feral house mice – a laboratory investigation of the influence of social structure,population density,and aggression

Emigration in small mammals may be strongly related to social factors, but direct observations of emigrants are rare. Feral house mice (Mus domesticus) were studied using a population cage system that allowed continuous observation of individually marked animals. Mice that left their natal cage and took up residence in cages that could only be reached by crossing a water barrier were defined as emigrants. Six pairs of house mice with their litters were placed in the system, and data on aggressive interactions, body weight, reproduction, mortality and emigration were collected daily. Both sexes emigrated, but males did so twice as often as females. Population density was not correlated with the frequency of aggression, and had no effect on the weight of emigrating individuals. Male emigrants suffered more aggression before emigration than their non-emigrant brothers of the same age; they were aggressively driven out by other males, predominantly by the father. Female emigration depended on the female’s chances of reproduction. The probability of a female reproducing decreased with increasing birth order. Females born in a late litter, who therefore had only a low chance of reproduction, dispersed earlier than those of early litters. Resident males were reproductively suppressed. Male offspring had two different strategies for attaining top rank. They could develop rapidly and reach sexual maturity early on, but face competition with the father, risking being forced to emigrate. Alternatively, they could develop slowly, stay within their family and wait for a chance to take over the dominant position. It is concluded that emigration in male and female feral house mice is caused by intrasexual competition. Received: 13 July 1995/Accepted after revision: 8 June 1996     

XDLVO理论解析钙离子对腐殖酸反渗透膜污染的影响机制

以XDLVO（extended Derjaguin-Landau-Verwey-Overbeek）理论定量解析腐殖酸反渗透（reverse osmosis,RO）膜污染过程中的界面相互作用,分析3种界面相互作用力在膜污染过程中的贡献,重点探究不同溶液pH条件下Ca2＋对腐殖酸RO膜污染的影响.结果表明,无论Ca2＋是否存在,对膜污染起促进作用的范德华力在pH 3时为主导作用力,而减缓膜污染的极性作用力在pH 7及pH 10时成为主控因素.静电力在所有测试条件下作用微弱,因此对膜污染贡献很小.Ca2＋主要通过改变极性作用力影响腐殖酸RO膜污染行为,且其影响随溶液pH值的降低而凸显,多数情况下Ca2＋会促进腐殖酸RO膜污染.界面自由能与膜污染程度相关性分析表明,XDLVO理论可以合理预测不同溶液条件下腐殖酸RO膜污染行为.     

Interactions in hazard management policies: the case of drought in Nicaragua, 1976–2010

The literature on adaptive and multi‐level governance calls for interactive hazard management to increase societies’ resilience. This paper maps the hazard management policies in a poor and hazard‐prone country—Nicaragua—and examines what role the government gives to interactions among different actors at different societal levels. A new analytical framework is developed that includes scope and direction to capture unidirectional or mutual interactions that are either horizontal or vertical. This enables a more complex analysis of interactions than that found in previous research. The review shows that the historical change in the role given to interactions, as a result of a focus on short‐term emergency response being complemented by long‐term risk management, mainly lies in how they are characterised—with more participants and other types of content categories—and the awareness that interactions other than mutual ones can be positive. This illustrates the complexity of the issue of interactions.     

Social innovation and the governance of sustainable places

This article explores social innovation as a tool for the promotion of place-based sustainable development. The literature highlights the satisfaction of basic needs and situations of crises as two major drivers of socially innovative actions. We use these insights to explore the conditions under which social innovation can lead to social transformation and sustainable place making. We also recognise that social processes occur through, and are shaped by, the material forms that constitute and are constituted in place-specific settings. This highlights the deep interconnections that exist between place making and the resources, attributes and characterises – the materiality (such as rivers, soil, trees) – that exist within that locality. It is here that a close tie can be discerned between understanding the adaptive process in complex socio-ecological systems and the role of social innovation in such adaptation. Socially innovative initiatives at the community level can also be scaled upwards through the co-ordinating role of the state, while at the same time act as a pressure for more participatory forms of governance. Governance processes that enhance the role of both economic and social actors in the steering of social change help to infuse more open, democratic practices into social steering. With social, economic and state actors co-mingling as agents of social change, social innovation can come to play a key role in enhancing sustainable human–environment interactions.     

The solution phase complexing of atrazine by fulvic acid: Equilibria at 25°c

Abstract

The solution phase complexing equilibria of atrazine by fulvic acid at 25°C±1.° have been investigated over the pH range of 1.3 to 6.0. Experiments with 0.1MKC1 and chelated Cu(II) are compared with those without metal ions. The use of a fulvic acid having calibrated acidic and Cu(II) chelation properties has made it possible to obtain stoicheometricly “exact”; chemical information. This is correlated with previous hydrolysis kinetics work. It is concluded that atrazine is hydrogen bonded in a labile equilibrium, to an identifiable set of protonated carboxyl groups, which act as Brönsted acid catalysts for hydrolysis. 0.1M KC1 changes (1‐α_A), the degree of protonation of the carboxyl groups, without otherwise affecting the atrazine complexing. Cu(II) chelation both reduces and weakens the complexing through a combination of carboxyl group blocking, and fulvic acid aggregation. Simple equations are presented for predictive calculations.     

Current Constraints and Future Directions in Estimating Coextinction

Abstract: Coextinction is a poorly quantified phenomenon, but results of recent modeling suggest high losses to global biodiversity through the loss of dependent species when hosts go extinct. There are critical gaps in coextinction theory, and we outline these in a framework to direct future research toward more accurate estimates of coextinction rates. Specifically, the most critical priorities include acquisition of more accurate host data, including the threat status of host species; acquisition of data on the use of hosts by dependent species across a wide array of localities, habitats, and breadth of both hosts and dependents; development of models that incorporate correlates of nonrandom host and dependent extinctions, such as phylogeny and traits that increase extinction‐proneness; and determination of whether dependents are being lost before their hosts and adjusting models accordingly. Without synergistic development of better empirical data and more realistic models to estimate the number of cothreatened species and coextinction rates, the contribution of coextinction to global declines in biodiversity will remain unknown and unmanaged.     

Indirect Effects in Aquatic Ecotoxicology: Implications for Ecological Risk Assessment

Understanding toxicant effects at higher levels of biological organization continues to be a challenge in ecotoxicology and ecological risk assessment. This is due in part to a tradition in ecotoxicology of considering the direct effects of toxicants on a limited number of model test species. However, the indirect effects of toxicity may be a significant factor influencing the manner in which ecosystem structure and function respond to anthropogenic stressors. Subsequently, failure to incorporate indirect effects into risk assessment paradigms may be a significant source of uncertainty in risk estimates. The current paper addresses the importance of indirect effects in an ecotoxicological context. Laboratory, mesocosm, and whole ecosystem research into indirect effects is reviewed. The implications of indirect effects for ecological risk assessment and potential areas of profitable future research are also discussed.