Mating strategies of queens in <Emphasis Type="Italic">Lasius niger</Emphasis> ants—is environment type important?

High relatedness among society members is believed important for the evolution of highly cooperative behaviours, yet queens of many social insects mate with multiple males which reduces nestmate relatedness and imposes also direct costs on queens. While theoretical models have suggested explanations for this puzzling queen behaviour, empirical studies fail to provide consistent answers especially for species with moderate levels of multiple mating. This may result from multiple mating only conferring benefits in some environments, as suggested by recent genetic variance theory and considerations on types of traits, direct costs and benefits. All concur in an expectation of higher levels of multiple mating in more complex or milder environments, and we perform a first, broad test of this idea by comparing mating strategies of queens in Lasius niger ants from northern (harsh, cold stressed) and southern populations (milder, greater bio-complexity). First, we collected new genetic data from Ireland and Southern France and then compared these to data on Swiss and Swedish populations. Queens from northern populations were near exclusively single mated and even at times inbred (in Ireland), whereas southern queens showed high levels of multiple mating, leading to more genetically diverse colonies in the south. Equally, paternity skew was greater in the north, as expected if northern queens only remate when their first mate transfers few sperm. Our findings are consistent with the idea that environment type may affect mating strategies in social insects and calls for an exploration of such effects.     

Stewardship Volunteering by Older Australians: The Generative Response

Abstract

The aim of this paper is to use Erikson's approach to human development, and specifically generativity, as a framework by which to explore older people's experiences of environmental stewardship activities. Using data from a large qualitative study of environmental volunteers resident in the coastal fringes of Queensland, Australia, the paper provides important, illustrative, empirical support for Erikson's theory of generativity in later life. Findings suggest that older people are much more likely to connect their environmental actions with the longer-term future, and express a need to leave a lasting legacy for future generations. According to respondents, the later years are a time to contribute to the environment as part of a broader cycle of life. The environment is also an important site for intergenerational activities. Whilst the work presented here is only a small, localized study, use of Erikson's theory of human development as a framework helps demonstrate the importance of a generative response in later life.     

“Unwritten,unsaid, just known”: the role of Indigenous knowledge(s) in water planning in Australia

Water planning processes in Australia have struggled to account for Indigenous interests and rights in water, including the use of Indigenous knowledge in water management. In exploring the role of Indigenous knowledge in government-led water planning processes, how might tensions between Western scientific and Indigenous knowledges be lessened? Drawing on two case studies from northern Australia we examine how Indigenous knowledge is represented and managed as a different social knowledge to that of Western science in a management context where legal and planning conventions assume priority. The role of Indigenous (social) knowledges in developing options and strategies for sustainable water management is contingent upon the participation of Indigenous people in water planning. We suggest that water planning processes must contain the possibility of an explicit approach to mutual recognition and consequent translation of the conceptual and pragmatic bases of water management and planning in both Western scientific and Indigenous domains.     

Rendering Bio-inert Low-Density Polyethylene Amenable for Biodegradation via Fast High Throughput Reactive Extrusion Assisted Oxidation

Journal of Polymers and the Environment - An energy-efficient high throughput pre-treatment of low-density polyethylene (LDPE) using a fast, reactive extrusion (REX) assisted oxidation technique...     

Concentrations,bioaccumulation, and health risk assessments of heavy metals in fishes from Nigeria’s freshwater: a general overview

Environmental Science and Pollution Research - Heavy metals (HMs) have attracted global attention due to their toxicity, persistence, and accumulation in aquatic fish in the polluted water...     

Ancient manuring practices pollute arable soils at the St Kilda World Heritage Site, Scottish North Atlantic

The impact of ancient fertilization practices on the biogeochemistry of arable soils on the remote Scottish island of Hirta, St Kilda was investigated. The island was relatively unusual in that the inhabitants exploited seabird colonies for food, enabling high population densities to be sustained on a limited, and naturally poor, soil resource. A few other Scottish islands, the Faeroes and some Icelandic Islands, had similar cultural dependence on seabirds. Fertilization with human and animal waste streams (mainly peat ash and bird carcases) on Hirta over millennia has led to over-deepened, nutrient-rich soils (plaggen). This project set out to examine if this high rate of fertilization had adversely impacted the soil, and if so, to determine which waste streams were responsible. Arable soils were considerably elevated in Pb and Zn compared to non-arable soils. Using Pb isotope signatures and analysis of the waste streams, it was determined that this pollution came from peat and turf ash (Pb and Zn) and from bird carcases (Zn). This was also confirmed by ¹³C and ¹⁵N analysis of the profiles which showed that soil organic matter was highly enriched in marine-derived C and N compared to non-arable soils. The pollution of such a remote island may be typical of other ‘bird culture’ islands, and peat ash contamination of marginal arable soils at high latitudes may be widespread in terms of geographical area, but less intense at specific locations due to lower population densities than on Hirta.     

Sequential extraction combined with isotope analysis as a tool for the investigation of lead mobilisation in soils: application to organic-rich soils in an upland catchment in Scotland

Sequential extraction (modified BCR procedure) combined with isotope analysis has been investigated as a tool for assessing mobilisation of lead into streams at an upland catchment in NE Scotland. The maximum lead concentrations (up to 110 mg kg(-1) in air-dried soil) occurred not at the surface but at about 10 cm depth. The lowest (206)Pb/(207)Pb ratios in any profile occurred, with one exception, at 2.5-5 cm depth. In the one exception, closest to the only road in the area, significantly lower (206)Pb/(207)Pb ratios in the surface soil together with much increased chloride concentrations (in comparison to other surface waters) indicated the possible mobilisation of roadside lead and transfer to the stream. The (206)Pb/(207)Pb ratios in extractable fractions tended at depth towards the ratio measured in the residual phase but the ratios in the oxidizable fraction increased to a value higher than that of the residual phase.