Diatoms from an ice-wedge furrow, Ungava Peninsula, Quebec, Canada

The first recorded information about living fresh water diatoms on an ice-wedge furrow is presented. One sample has been analysed and two species, Cymbella aequatis and Tabellaria flocculosa , formed almost half of the diatom population. Some rather rare species for the Canadian Eastern Arctic were identified: Fragilaria constricta, Eunotia lunaris, Eunotia microcephala, Pinnularia gibba, Anomoeoneis zellensis , and Cymbella aspea . Of the 37 species identified, most are common elsewhere in the Arctic.     

Tardigrada from the Husvik area, South Georgia, sub-Antarctic

Eleven species of tardigrades in South Georgia, of which two are new to science, were found in samples collected at fifteen localities. The highest number of species was found in moss from a scree field. Twenty species of tardigrades are presently known from South Georgia, but the island remains insufficiently investigated. The species composition is similar to that of southern South America. The high number of cosmopolitan species makes the geographical distribution pattern of the South Georgian tardigrades more similar to that of macrolichens than to that of insects and vascular plants.     

Palaeoenvironmental Reconstruction from Near-Surface Pan Sediments: An Example from Lebatse Pan, Southeast Kalahari, Botswana

Recent studies of pan sediment stratigraphy in southern Africa have indicated the potential of geophysical and geochemical analyses for elucidating the evolution of pans and the environmental conditions under which formation took place. We have investigated three cores, of 1.8 to 2.6 m in length, from Lebatse Pan in southeast Kalahari, Botswana, and compare the results with the few other similar studies available. Through the sedimentological characteristics of Lebatse we identify cycles of deposition, chemical precipitation and post-depositional alteration under shifting environmental conditions from c . 60,000 years ago to the present. Four periods are separated by depositional hiatuses, marking dry conditions during which deflation of the pan cannot be excluded. During the two oldest periods the sequence of finely laminated, magnesia-rich sediments suggests deposition in a permanent shallow waterbody under evaporative conditions, causing chemical precipitation of dolomite from groundwater. Less evaporative conditions are inferred for the third period of deposition between hiatuses H2 and H1. The youngest period, ¹⁴C-dated to 29,000 years BP, is characterised by water-logged conditions and the development of reed beds. It is believed to have been laid down under fluctuating water levels. The cycles of deposition exhibited in the pan cores appear synchronous with wetter periods in the Southern Kalahari, indicated by the limited evidence currently available.     

Marxism, Sarcasm, Ethnography: Geographical Fieldnotes from South India

This paper addresses questions of ethnography in geographic fieldwork through research conducted on globalisation and work in Tiruppur, an industrial boomtown in South India. During the last two decades of the twentieth century, Tiruppur town in western Tamilnad State became India's centrepiece in the export of garments made of knitted cloth. This industrial boom has been organised through networks of small firms integrated through intricate subcontracting arrangements controlled by local capital of Gounders from modest agrarian and working‐class origins. In effect, the whole town works like a decentralised factory for the global economy, but with local capital of peasant‐worker origins at the helm. My research explores the historical geographic trajectories linking agrarian and industrial work, and the ways in which these histories are used in the present. In these uses of the past in remaking self and place, I interrogate the self‐presentations of Tiruppur's entrepreneurs, as these “self‐made men” hinge their retrospective narratives of class mobility and industrial success on their propensity to “toil”. This paper explores questions of ethnographic method emerging from a political‐economic context in which globalisation has worked by turning “toil” into capital.     

旅游影响下民族村寨社会空间演化过程与机理研究——以贵州西江苗寨为例

旅游影响下民族村寨社会空间结构急剧变迁。研究基于社会空间“物质性与精神性” 的统一,以贵州西江苗寨为例,综合遥感解译分析、GIS空间分析及定性分析等方法,揭示了旅游影响下民族村寨社会空间演化过程与机理。研究发现：①西江苗寨空间形态和功能演化规律与旅游发展线性相关,整体呈现抱团集聚、垂直分异与旅游异质性的特征;村寨从生活自居空间转化为多元势力协商的空间,并逐步演化为以旅游为主导的混合型空间,内部差异显著。②村寨社会空间演化动力源于利益主体对空间资源的占据和生产的“推力”以及游客对异质文化的诉求的“拉力”叠加。③“空间实践、空间再现以及再现的空间”的生产逻辑成为村寨社会空间演化机理。④旅游影响下村寨社会空间演化呈现非均衡性实践特征,权利-资本空间“簇”和“柱”形成,但村寨精神文化空间仍就稳固。该研究为后续社会空间物质性与精神性转换关系、路径以及机制提供一定指引。     

Ordovician conodonts from the Bulltinden Formation, Motalafjella, central-western Spitsbergen

Seven samples from the Limestone and Boulder Conglomerate Members of the Bulltinden Formation have yielded poorly preserved conodonts. On tentative identifications Periodon aculeatus Hadding and Prioniodus cf. P. alobatus Bergstrom at the base of the formation suggest an Ordovician lower Caradoc, or older age. This confirms that the Vcstgotabrcen Formation unconformably beneath underwent high-pressure mctamorphism during the Taconic and/or Finmarkian phases of the Caledonian orogeny. The conodonts show affinity to the North Atlantic Province suggesting a deeper water marine depositional environment. Conodont colour alteration indices of five indicate that the Bulltinden Formation was heated to temperatures in excess of 300°C, probably during the middle-upper Silurian main Caledonian uplift event.     

Diatom-inferred lake level from near-shore cores in a drainage lake from the Experimental Lakes Area,northwestern Ontario,Canada

We inferred late Holocene lake-level changes from a suite of near-shore gravity cores collected in Lake 239 (Rawson Lake), a headwater lake in the Experimental Lakes Area, northwestern Ontario. Results were reproduced across all cores. A gravity core from the deep central basin was very similar to the near-shore cores with respect to trends in the percent abundance of the dominant diatom taxon, Cylcotella stelligera. The central basin, however, does not provide a sensitive site for reconstruction of lake-level changes because of the insensitivity of the diatom model at very high percentages of C. stelligera and other planktonic taxa. Quantitative estimates of lake level are based on a diatom-inferred depth model that was developed from surficial sediments collected along several depth transects in Lake 239. The lake-level reconstructions during the past ~3,000 years indicate that lake depth varied on average by ±2 m from present-day conditions, with maximum rises of ~3–4 m and maximum declines of ~3.5–5 m. The diatom-inferred depth record indicates several periods of persistent low levels during the nineteenth century, from ~900 to 1100 AD, and for extended periods prior to ~1,500 years ago. Periods of inferred high lake levels occurred from ~500 to 900 AD and ~1100 to 1650 AD. Our findings suggest that near-shore sediments from small drainage lakes in humid climates can be used to assess long-term fluctuations in lake level and water availability.     

Eight new ornithological records from Xinjiang,China

在2006年10月14日-11月8日,笔者在新疆北部观鸟期间,观察到8种鸟类属于新疆新记录:小白额雁(博乐)、斑背潜鸭(石河子、赛里木湖)、长尾鸭(赛里木湖)、剑鸻(玛纳斯)、海鸥(伊犁、石河子、五家渠)、灰椋乌(沙湾)、红喉鹨(石河子、五家渠)、黄腹鹨(石河子、五家渠、阜康等).其中的4种鸟类被拍摄到照片.新疆地域辽阔,鸟类资料缺乏(马鸣2001).此次调查是个极好的补充.     

Inventory of Glaciers in Mongolia,Derived from Landsat Imagery from 1989 to 2011

Glaciers in the Altai Mountains of Mongolia provide an estimated 11% of the total water resources within the country. Yet, their number and area in inconsistent. Using satellite imagery acquired from Landsat 4, 5, and 7, and SRTM digital elevation model (DEM) data, we present here an intuitive, robust, and inexpensive methodology to map the exposed ice of glaciers in the Altai Mountains for the period 1989 to 2011. The total glacierized area was 515 km² in 1989/1991, 428 km² in 1998/2001, and 372 km² in 2010/2011; it decreased by 17% from 1989/1991 to 1998/2001, 13% from 1998/2001 to 2010/2011, and 28% for the entire period 1989/1991 to 2010/2011. In analyzing a sub‐sample of 260 glaciers, 6% advanced, 11% were stable, and 83% receded from 1989 to 2011. The glacier dataset is available to the public free of charge at the Global Land Ice Measurements from Space (GLIMS) website.     

The structure of King's Trough, Northeast Atlantic, from bathymetric, seismic and gravity studies

Summary . We present new seismic and gravity data from the linear chain of deeps and flanking ridges known collectively as King's Trough, and combine them to produce crustal models of the western end of the complex. These models show that there is an abnormally low-velocity, low-density crust under the trough itself, and that the whole King's Trough feature is situated in a region of slightly thicker than normal oceanic crust. The flanks and basins of King's Trough are not in local isostatic equilibrium, although the feature now appears to be inactive. We believe these data indicate a history of extension and of hot-spot activity at King's Trough, and that the feature was formed either as a slow-spreading arm of an R-R-R triple junction associated with a Mid-Atlantic Ridge hot-spot, or by subsequent rifting of a preexisting hot-spot trace.     

Maize diversity, rural development policy, and farmers' practices: lessons from Chiapas, Mexico

Maize diversity is important to the livelihoods of millions of farmers in Mexico, the crop's centre of origin; to maize breeders seeking new genetic material; and to producers and consumers worldwide. Key social processes that determine maize diversity include historic and cultural emphases on maize as a primary crop; land-use practices encompassing heterogeneous agro-ecological conditions; farmers' seed-saving practices; farmer selection of useful traits; and farmer seed exchange and purchasing networks. We consider the impacts of recent agricultural and rural development policies on these processes. We focus on La Frailesca, a commercial and semi-subsistence maize-growing region in southern Mexico. Qualitative data were collected via focus group discussions, semi-structured interviews, and participant observation in four villages at intervals over a 2-year period. These techniques were complemented with semi-structured interviews with local and state policymakers. Observations suggest that policies promoting market liberalisation, agricultural modernisation, and rural education have contributed to significant changes in the social processes which have historically generated maize diversity. Increasing numbers of smallholder maize producers are diversifying into alternative livelihood options, including temporary or permanent migration, and cultural and economic emphases on maize production are changing. Changes in La Frailesca raise important questions about the fate of maize genetic diversity as the Mexican agricultural sector is further realigned with the global agricultural economy.     

Oscillaxanthin and myxoxanthophyll in two cores from Lake Wabamun,Alberta, Canada

A sedimentary blue-green algal record has been investigated through measurement of myxoxanthophyll and oscillaxanthin in two cores taken from deep and shallow sites in Lake Wabamun, Alberta, Canada (Longitudes 114° 26 and 114° 44 W; Latitudes 50° 30 and 50° 35 N). Blue-green algae have been a component of the algal flora of this lake throughout the Holocene period. Myxoxanthophyll and oscillaxanthin maxima occur in early Holocene sediments (ca. 9000 years BP), whereas oscillaxanthin concentrations are high between 7000 and 3800 years BP. High oscillaxanthin levels suggest that a phytoplankton assemblage, which included Oscillatoria spp., existed during this latter period and the lake was more eutrophic than at present. Decreases in the number of planktonic diatoms in the core from the deep site (Seba core) appear to be related to increased eutrophy, increased salinity, and sediment redistribution as well as possible competition with Oscillatoria. That the lake has been less productive during the last 2500 years in supported by the diatom record, the diatom: chrysophyte statospore (stomatocyst) ratio and concentrations of the blue-green algal pigments. In the core from the shallow site (Moonlight Bay) concentrations of blue-green algal pigments are initially high, which along with the diatom assemblage, indicates a younger basal age of the sediments. It is possible that benthic blue-green algae contributed significantly to sedimentary pigment concentrations in the Moonlight Bay core. Major fluctuations in the Osc: Myx ratio, particularly in the Seba core, casts some doubt upon the usefulness of this ratio, and suggests that it is not degradation-independent.     

Isolation,identification and characterization of highly tellurite-resistant,tellurite-reducing bacteria from Antarctica

The tellurium oxyanion, tellurite, is extremely noxious to most living organisms. Its toxicity has been mainly related to the generation of reactive oxygen species (ROS) as well as to an unbalancing of the thiol:redox buffering system. Nevertheless, a few bacteria are capable of thriving at high tellurite concentrations. One mechanism of resistance is the enzymatic and non-enzymatic reduction of tellurite to the less toxic elemental tellurium. This reduction generates nano- to micrometric tellurium crystals that display different shapes and sizes.To date, a very limited number of highly tellurite-resistant and tellurite-reducing bacterial species are available from international culture collections. In this work, we decided to look for tellurite-reducing bacteria from an extreme environment, Antarctica. This environment exhibits a combination of several extreme factors such as high UV-radiation and desiccation and freezing conditions that impact directly on the local biodiversity. Since, as does, all these factors induce ROS formation, we hypothesized that Antarctic bacteria could also exhibit tellurite-resistance. In this context, we isolated 123 tellurite-resistant bacteria, and characterized six new tellurite-resistant and tellurite-reducing bacterial strains from samples collected in Antarctica. These strains were identified according to their 16S rRNA gene sequence as Staphylococcus hameolyticus, Staphylococcus sciuri, Acinetobacter haemolyticus, Pseudomonas lini, and two strains of Psychrobacter immobilis.The isolates display tellurite-resistance about 35- to 500-fold higher than Escherichia coli (Te-sensitive organism), and a high level of tellurite reduction which might be interesting for an application in the field of bioremediation or nanoparticle biosynthesis.     

Impact of pre-Columbian agriculture, climate change, and tectonic activity inferred from a 5,700-year paleolimnological record from Lake Nicaragua

Lake Nicaragua, the largest lake in Central America, is a promising site for paleolimnological study of past climate change, tectonic and volcanic activity, and pre-Columbian agriculture in the region. It is near the northern limit of the Intertropical Convergence Zone (ITCZ), which brings the rainy season to the tropics, so effects of decreasing precipitation due to southern migration of the ITCZ through the Holocene should be observable. Because fault zones and an active volcano lie within the lake, the long-term impact of tectonic and volcanic activity can also be examined. Finally, the fertile volcanic soils near the lake may have encouraged early agriculture. We analyzed diatoms, biogenic silica (BSi), total organic carbon (TOC), water content, volcanic glass, and magnetic susceptibility in a sediment core from Lake Nicaragua with eleven accelerator mass spectroscopy radiocarbon dates, spanning ~5,700 years. Sediment accumulation rates decreased from the bottom to the top of the core, indicating a general drying trend through the Holocene. An increase in eutrophic diatom abundance suggests that pre-Columbian agriculture impacted the lake as early as ~5,400 cal yr BP. Above a horizon of coarser grains deposited sometime between ~5,200 and 1,600 cal yr BP, planktonic diatoms increased and remained dominant to the top of the core, indicating that water depth permanently increased. Although magnetic susceptibility peaked and water content dipped at the coarse horizon, volcanic glass fragments did not increase, suggesting that the coarse horizon and subsequent increase in water depth were caused by tectonic rather than by volcanic activity. Decreased accumulation rates of BSi and TOC indicate that water became clearer when depth increased.     

Heavy metals in water, ice and biological material from Spitsbergen, Svalbard

Concentrations of heavy metals Zn, Mn, Cu, Fe, Ni, Cr, Pb, Cd, Hg and Co were determined in surface waters, glacier ice and plant and animal materials from three regions in Spitsbergen, Svalbard. The concentrations of these metals in two samples of surface waters and in the vascular plants from Spitsbergen were found to be lower than what is commonly found in Cental Europe. Elevated concentrations were found in old ice from the surface of a glacier. The concentrations of heavy metals in algae were lower than in vascular plants. The concentrations of metals in the samples of feathers and animal hair from Spitsbergen were higher than what is common for Central Europe.     

Timing of breeding in free-ranging Ethiopian hedgehogs,Paraechinus aethiopicus,from Qatar

There is little information pertaining to the breeding behaviour and reproductive biology of free-ranging hedgehog populations outside of Europe. We monitored the seasonal changes in courtship behaviour and the presence of new young animals from a free-ranging Ethiopian hedgehog population in Qatar between 2010 and 2012. Based on frequencies of courtship behaviour and deduced frequencies of successful mating, the mating season of the Ethiopian hedgehog is believed to start in January and continue through until July with a clear peak during the February/March period. We propose the existence of two mating peaks, one in February/March and the second in June, suggesting that free-ranging Ethiopian hedgehogs breed more than twice a year in Qatar. Successful mating in late winter/early spring may be more important for the increasing the inclusive fitness of the parents based on the number of young individuals that survive beyond one month of age.