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201.
202.
Jane M. Ferguson 《Singapore journal of tropical geography》2014,35(3):295-311
This article traces the revenue category and legal concept of the Waste Land in Burma/Myanmar from its original application by the British colonial apparatus in the nineteenth century, to its later use in tandem with Burma Army counterinsurgent tactics starting in the 1960s, and finally to the 2012 land laws and current issues in international investment. This adaptation of colonial ideas about territorialization in the context of an ongoing civil war offers a new angle for understanding the relationship between military tactics and the political economy of conflict and counterinsurgent strategies which crucially depended on giving local militias—both government and nongovernment—high degrees of autonomy. The recent government changes, including the more civilian representation in parliament and its shift to engage with Western economies, raise questions regarding the future of the military, as well as local autonomy and the rural peasantry's access to land. As increasing numbers of international investors are poised to enter the Myanmar market, this article will revisit notions of land use and appropriation, and finally the role of the army and its changing relationship with Waste Lands. 相似文献
203.
The Twentieth Century Reanalysis (20CR) holds the distinction of having the longest record length (140-year; 1871–2010) of any existing global atmospheric reanalysis. If the record can be shown to be homogenous, then it would be the first reanalysis suitable for long-term trend assessments, including those of the regional hydrologic cycle. On the other hand, if discontinuities exist, then their detection and attribution—either to artificial observational shocks or climate change—is critical to their proper treatment. Previous research suggested that the quintupling of 20CR’s assimilated observation counts over the central United States was the primary cause of inhomogeneities for that region. The same work also revealed that, depending on the season, the complete record could be considered homogenous. In this study, we apply the Bai-Perron structural change point test to extend these analyses globally. A rigorous evaluation of 20CR’s (in)homogeneity is performed, composed of detailed quantitative analyses on regional, seasonal, inter-variable, and intra-ensemble bases. The 20CR record is shown to be homogenous (natural) for 69 (89) years at 50 % of land grids, based on analysis of the July 2 m air temperature. On average 54 % (41 %) of the grids between 60°S and 60°N are free from artificial inhomogenetites in their February (July) time series. Of the more than 853,376 abrupt shifts detected in 26 variable fields over two monthly time series, approximately 72 % are non-climate in origin; 25 % exceed 1.8 standard deviations of the preceding time series. The knock-on effect of inhomogeneities in 20CR’s boundary forcing and surface pressure data inputs to its surface analysis fields is implicated. In the future, reassessing these inhomogeneities will be imperative to achieving a more definitive attribution of 20CR’s abrupt shifts. 相似文献
204.
205.
Gillian D. Lewis Angela Hough David H. Green John E. Hay Lynnette R. Ferguson 《新西兰海洋与淡水研究杂志》2013,47(4):443-447
Human viruses are a common contaminant of shellfish affected by human sewage wastes. They are difficult to detect as they are not easily separated from shellfish tissue. This paper describes a modification of the polyethylene glycol (PEG) precipitation technique for recovery of enteroviruses and F‐specific bacteriophages from the Pacific oyster (Crassostrea gigas) and the green‐lipped mussel (Perna canaliculus). Modifications adopted were the use of only the digestive gland tissue for virus extraction, resuspension of the primary PEG pellet in 4 volumes of eluent, and the introduction of a secondary PEG precipitation to reconcentrate the virus containing extract. The recovery rate of the virus extraction process was not affected by introduction of the secondary concentration step (overall recovery remained at 60–70% of the virus input). The advantages of reduction of tissue residue in the extract, smaller final volume, and the ability to process 2–3 times the number of individual shellfish for the same effort, improve the practicality of the method. 相似文献
206.
ANDREAS D. MUELLER FLAVIO S. ANSELMETTI DANIEL ARIZTEGUI MARK BRENNER DAVID A. HODELL JASON H. CURTIS JAIME ESCOBAR ADRIAN GILLI DUSTIN A. GRZESIK THOMAS P. GUILDERSON STEFFEN KUTTEROLF MICHAEL PLÖTZE 《Sedimentology》2010,57(5):1220-1245
Long sediment cores were collected in spring 2006 from Lake Petén Itzá, northern Guatemala, in water depths ranging from 30 to 150 m, as part of an International Continental Scientific Drilling Program project. The sediment records from deep water consist mainly of alternating clay, gypsum and carbonate units and, in at least two drill sites, extend back >200 kyr. Most of the lithostratigraphic units are traceable throughout the basin along seismic reflections that serve as seismic stratigraphic boundaries and suggest that the lithostratigraphy can be used to infer regional palaeoenvironmental changes. A revised seismic stratigraphy was established on the basis of integrated lithological and seismic reflection data from the basin. From ca 200 to ca 85 ka, sediments are dominated by carbonate‐clay silt, often interbedded with sandy turbidites, indicating a sediment regime dominated by detrital sedimentation in a relatively humid climate. At ca 85 ka, an exposure horizon consisting of gravels, coarse sand and terrestrial gastropods marks a lake lowstand or partial basin desiccation, indicating dry climate conditions. From ca 85 to ca 48 ka, transgressive carbonate‐clay sediments, overlain by deep‐water clays, suggest a lake level rise and subsequent stabilization at high stage. From ca 48 ka to present, the lithology is characterized by alternating clay and gypsum units. Gypsum deposition correlates with Heinrich Events (i.e. dry climate), whereas clay units coincide with more humid interstadials. 相似文献
207.
A modified morphodynamic model for investigating the response of rivers to short-term climate change
Patrick M. Verhaar Pascale M. Biron Robert I. Ferguson Trevor B. Hoey 《Geomorphology》2008,101(4):674-682
Near-future climate change will affect the discharge and base level of rivers and thus cause channel changes. The nature and pace of such changes can be simulated using morphodynamic models. As part of an investigation of how the changing hydrology of the St-Lawrence River, Quebec, Canada, will affect its tributaries we have made additions and modifications to a one-dimensional morphodynamic model developed for gravel-bed rivers (SEDROUT). The changes allow simulation of sand-bed rivers, variable discharge, downstream water level fluctuations, and flow and sediment routing in channels with islands. A revised formulation for calculating the grain size distributions of the surface and subsurface material is presented to allow for alternating sedimentation and erosion. We test the enhanced model using small-scale simulations and present-day conditions in four tributaries of the St-Lawrence River. The model is calibrated and validated for the tributaries and the capability to simulate river morphology over a 100-year period is tested. Good validation agreement on water level, cross-sectional mean velocity, and sediment transport rate is obtained for the four tributaries of the St-Lawrence River. With these modifications, modelling a very wide range of river morphodynamic problems is now possible. 相似文献