A trade-off between structural and chemical defences against herbivory in woody plants is alleged to depend on edaphic factors in African savannas. We studied anti-herbivory traits, in an edaphic mosaic of fertile and infertile soils within a savanna landscape in East Africa, towards elucidating herbivory defence traits expressions in woody plants of African savannas. We used data of 81 plants for 8 species from 8 sites — four sites from fertile soils (42 plants) and another four sites from infertile soils (39 plants). We did not find a general divide between structural and chemical strategies in our data. Instead, we found a range of defence traits combinations. Our results highlight that in woody plants of African savannas, chemical and structural defences can augment each other, and not necessarily trade-off. The diversity of herbivores, ranging from insects to mesobrowsers, may have driven the evolution of multiple defence strategies within the African savannas.

Currently, a substantial proportion of Antarctic research is carried out through deployment of field camps, but little detailed information on the running of these facilities is often available. The remoteness of camps and the fragility of local Antarctic terrestrial ecosystems make the running of sustainable, low impact field science and logistics in ice-free areas a challenge for environmental managers. In this study we examined the environmental management at the Spanish camp within Antarctic Specially Protected Area (ASPA) No. 126 Byers Peninsula, Livingston Island, South Shetland Islands. Firstly, the input of materials and generation of pollution associated with the camp during a ten year period of operation was quantified. Examination of greenhouse gas emissions shows a mean of 14 t CO2 equivalent per researcher associated with transportation of people to the site, plus 44 t CO2 equivalent per researcher, associated with transportation of cargo to the field site. Secondly, the cumulative trampling footprint across Byers Peninsula and associated local impacts were recorded. Results showed the pattern of human movement within the ASPA and how activities concentrated around the field camp site. At the same time every effort was taken to ensure scientific outputs from research activities within the ASPA were maximized. Practical recommendations on operational logistics are discussed to minimize environmental impacts and optimize scientific benefits.

After a decade of research, New Zealand’s Latitudinal Gradient Project (LGP) now includes primary sites from Cape Hallett (72°S) to the Darwin Glacier (80°S), while additional observations extend the latitudinal transect from 84°S to sub-Antarctic regions. The LGP has been structured around a hypothesis that, in a frigid continent, ice dynamics is the key ecosystem variable. For terrestrial environments, two aspects of ice dynamics appear to underlie much of the observed variability. Firstly, the aridity of the region makes the transition from ice to water a key ecological factor, and secondly, the legacy of ice dynamics dating as far back as the Pliocene is imprinted on biogeography. These factors operate at difference temporal and spatial scales and neither is monotonically related to latitude. Both are also complicated by meso-scale cross gradients of altitude and distance from the sea and micro-scale local variability. Whilst climate does vary on a broad-scale, differences within the northern and central parts of Victoria Land that the LGP has so far examined are insufficient to impose any overarching effect that can overwhelm these more local effects. The result is a multiple-scale patchwork of habitats and communities, more or less replicated across the transect, in which variability at any given latitude generally exceeds variability between latitudes. A lesser quantum of research has been directed at marine ecosystems, but here there is a similar picture of local variability dominating within the Ross Sea, with significant latitude-scale effects only emerging when transects are extended into maritime- and sub-Antarctic regions. It is implicit, but not specifically recognized in the LGP context, that a further confounding effect on the interpretation of ‘transect’ information is the multiple stressor concept that requires a simultaneous analysis of interacting (synergistic or antagonistic) factors and environmental responses. As the LGP continues to extend further south, climate is expected to become more extreme, and water availability may change sufficiently for loss of habitat and species diversity to occur. Here we discuss options for refining the LGP approach to optimize its potential for understanding variability, and the factors underpinning this, in the Ross Sea Sector.

Eleven aerobic heterotrophic bacteria isolated from soil samples taken at c. 1800 m altitude from La Gorce Mountains, Antarctica, were characterized in terms of carbon source utilization, enzymatic activities and tolerance to environmental stressors. The bacteria typically formed pigmented colonies on agar plates and were initially observed on media designed for isolation of algae and cyanobacteria. The bacteria were purified and assigned to the Actinobacteria, Bacteroidetes or Proteobacteria divisions following 16S rRNA gene sequence analysis. While some of the isolates are most likely to belong to the genera Arthrobacter or Brevundimonas, others may belong to novel genera or species. The Gram-positive Actinobacteria used the widest range of carbon sources for growth. Brevundimonas P7 produced lipases, phosphatases, proteases and glycosyl-hydrolases. The Gram-positive bacteria were more tolerant to freeze-thaw than the Gram-negative isolates. No isolates survived more than 10 minutes ultraviolet irradiation. All isolates were unaffected by 24 h desiccation. This study adds to knowledge of the bacterial diversity of soils from high altitude (1800 m), high latitude (86°30'S) locations within Antarctica.