Climate change and community resilience in Samoa

Being resilient in the face of climate change seems especially important for island societies, which face the effects of rising temperatures, unpredictable rainfall, changing wind patterns and sea level rise. To date, most studies of adaptation and resilience among Pacific island communities have used indicators and methods rooted in Western science and neo-classical economics. These have been criticized as being locally irrelevant and inadequate to appreciate the dynamic nature and social structures of island communities and their capacity to adapt. This paper challenges the paradigm that defines resilience as a return to equilibrium, by using a non-equilibrium, cultural ecological lens. The non-equilibrium view of resilience sees the social systems of island nations as highly dynamic and undergoing persistent adaptation in the face of changing environmental factors. Field-based research undertaken in eight villages in Samoa found that, through constant exposure to environmental change over extended periods of time, communities have become resilient and are in a position to adapt to future changes. In developing future policy in relation to climate change, Pacific island governments need to develop a more nuanced understanding of islanders’ perceptions and historical actions in the context of both their physical locations and their dynamic socio-cultural systems.     

Presence of microplastics in the tube structure of the reef-building polychaete Gunnarea gaimardi (Quatrefages 1848)

The prevalence of microplastics in the marine environment has resulted in a need to understand their association with various fauna. The aim of this study was to assess whether microplastic particles are present in the tube structure of the indigenous reef-building polychaete Gunnarea gaimardi, which occurs along the coast of South Africa. Sampling was conducted at nine stations along the west and southeast coastlines of South Africa, in July 2016 and April/May 2017. Microplastic particles were recorded in all tube structures of G. gaimardi, with the density ranging between 0.056 and 1.113 microplastic particles g^–1 dry weight (dwt). There were no significant differences between sites (p > 0.05), resulting in an overall average of 0.275 (SD 0.215) microplastic particles g^–1 (dwt). To the authors’ knowledge, this is the first study to show that synthetic polymers are found in the tubes of reef-building polychaetes along the coast of South Africa.     

The bed morphology of upland single‐thread channels in semi‐arid environments: evidence of repeating bedforms and their wider implications for gravel‐bed rivers

Single‐thread, gravel‐bed streams of moderate slope in the northern Negev are characterized by three channel units: bars exhibit steeper than average slopes and poorly sorted mixtures of small–medium cobbles and coarse–very coarse pebbles; flats are associated with more gentle slopes and well‐sorted medium–fine pebbles and granules; and transitional units have intermediate slopes and grain size. In general, all three units are planar, span the full channel width and have well‐defined boundaries. Bars and flats are more common than the transitional units and alternate downstream for distances of several hundred metres, forming sequences that are reminiscent of the riffle–pool structure commonly observed in humid‐temperate gravel‐bed rivers. A notable contrast is the absence of significant bed relief: bars lack crests and flats lack depressions. The relative lack of bed relief in bar–flat sequences is attributed to the high rate of sediment supply from the sparsely vegetated hillslopes which promotes the infilling of depressions and to the erosion of crests under conditions of intense transport. This reduction of bed relief lowers channel roughness, which in turn increases flow velocity and, therefore, the ability of the channel to transmit the large sediment loads it receives. Although our analyses pertain to a semi‐arid river system, the results have wider implications for understanding the adjustment of channel bedform to high sediment loads in other fluvial environments. Copyright © 2012 John Wiley & Sons, Ltd.     

The effect of low-level kelp supplementation on digestive enzyme activity levels in cultured abalone Haliotis midae fed formulated feeds

Previous studies have found that macroalgal inclusion in formulated diets for cultured abalone improves feed utilisation, and it was suggested that seaweed-associated bacteria supply enzymes that aid in the animal's digestion. In the present study, we hypothesised that kelp supplementation in formulated feed affects the profile of digestive enzymes in farmed Haliotis midae. Commercially reared sub-adult abalone fed a kelp-supplemented (Ecklonia maxima; 0.88% dry weight) or kelp-free control feed were collected for analysis of the amylase, alginate lyase, laminarinase, fucoidanase and protease activities in the gut. Levels of polysaccharidase and protease activity did not significantly differ between the diet treatments. However, enzyme-activity levels were more variable in abalone fed the kelp-free diet as compared with those fed the kelp-supplemented diet (coefficients of variation: 73%, 48.3–60.2% and 31.9% [control diet] versus 42.7%, 13.6–33.8% and 14.6% [KS diet] for amylase, macroalgal polysaccharidases and acid protease activity, respectively). We suggest that the presence of dietary kelp modulates the abalone's gut bacteria and their nutrient exchange. Proteomic identification of proteins in abalone gut sections showed that exogenous enzymes associated with the gut microbiome aid in bacterial utilisation of digested molecules, whereas abalone endogenous enzymes degrade the macronutrients in formulated feeds.     

Surface‐climate attributes at Injisuthi Outpost,Drakensberg, and possible ramifications for weathering

Aerial and sub‐aerial climatic data were collected from a station at 1920 m a.s.l. in the Injisuthi region of the South African Drakensberg. Sensors monitored air temperature, soil surface and rock surface temperature, for two rock types, over the summer and winter of 2001/2002. Rainfall was measured from the summer of 2001 to January 2004. These are the first rock and soil surface‐climate data to be collected for an exposed site at this altitude in the area. Rainfall over the two calendar years 2002 and 2003 was found to be below estimates for the region, but patterns imply numerous rock wetting and drying cycles in summer. At the site, air, rock and soil temperatures differ considerably on a diurnal basis with respect to both absolute temperature and daily ranges. Mean rock daily ranges, as conducive to possible thermal fatigue, are found to be similar in the summer and winter periods. Of the two rock types monitored, the darker coloured basalt attained higher maximum and marginally lower minimum temperatures than the sandstone. Soil frost did not occur at 2·5 cm depth, but rock did reach below ?6 °C in winter. Both rock types maintain relatively high rock temperatures in winter (exceeding 25 °C), thus chemical weathering is probably only moisture restricted during this dry period. Findings highlight the importance of directly monitoring rock temperature when attempting to discern the rock weathering environment. Copyright © 2006 John Wiley & Sons, Ltd.     

The first fossil Compsocidae from Cretaceous Burmese amber (Insecta, Psocoptera, Troctomorpha)

The first fossil record of the Compsocidae, Burmacompsocus perreaui gen. et sp. nov., is described from Late Albian Burmese amber. Its strong similarity to the two extant compsocid genera suggests a remarkable morphological stability within this group of 100 Ma. This family, now known only in Central America, was certainly more widespread in the past.     

Spiny plants in the archaeological record of Israel

The flora of Israel, like in other arid regions, has many spiny plants. We describe their existence in the archaeobotanical record of the last 780,000 years. Of 246 spiny/thorny species in the current flora, 19 are trees, 37 are shrubs, 50 are half-shrubs, 83 are perennial herbs and 57 are annuals. Forty-six (18.7%) spiny/thorny species were identified in the archaeobotanical record: 15 tree species (78.9%), ten shrub species (27.0%), six half-shrub species (12.0%), three perennial herb species (3.6%) and 12 annuals (21.1%). Because humans needed wood, trees were taken into their habitats. Since trees are better preserved than herbaceous plants and shrubs their remains are more common. Only a small proportion of the spiny/thorny half-shrubs and perennial herbs was found, probably because they are not a good source of firewood, construction materials, or human food. Spiny weeds, and segetal and ruderal plants entered the archaeobotanical remains either by chance, as seeds contaminating grain and fodder, growing at the sites, or through their deliberate use by ancient peoples as supplementary foods and medicine. The identified spiny/thorny species in the archaeobotanical record of Israel indicates that the flora was always spiny even before the significant human impact in the last several millennia.     

A new extraordinary neuropterid family from the Lower Cretaceous Crato Formation of Brazil: a new insect order? (Insecta, Neuropterida)

A new, highly specialized family, Rafaelidae, is proposed for two new lacewing-like species from the Lower Cretaceous Crato Formation in the Araripe Basin, Brazil. They have body and wing venation characters that are unique within the neuropterid insects, i.e., head, ovipositor, organization of the radial and median veins and structure of the subcostal vein. This new family cannot be attributed to any known insect order with certainty. These discoveries support the hypothesis of a considerable morphological disparity between neuropterid insects during the Early Cretaceous, as for the Odonatoptera.