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351.
May Christine Modenesi-Gauttieri Silvio Takashi Hiruma Claudio Riccomini 《Geomorphology》2002,43(3-4)
Integration of landform and structural analysis allowed the identification of Late Pleistocene–Holocene pulses of tectonic activity in the Campos do Jordão Plateau with ages and regimes similar to the ones from the continental rift. Fault reactivation along Precambrian shear zones give rise to a series of conspicuous morphotectonic features, determine the formation of stream piracy phenomena, and divide the plateau into smaller blocks. Recognition of these tectonic pulses as well as of their effects in landform development—particularly clear on the Campos de São Francisco at the highest area of the SE edge of the plateau—show that besides the climate-related Quaternary environmental changes significant neotectonic instability should be considered in the geomorphic evolution of the Campos do Jordão Plateau. 相似文献
352.
Jorge Andres Morandé Christine M. Stockert Garrett C. Liles John N. Williams David R. Smart Joshua H. Viers 《Carbon balance and management》2017,12(1):5
Background
Quantifying terrestrial carbon (C) stocks in vineyards represents an important opportunity for estimating C sequestration in perennial cropping systems. Considering 7.2 M ha are dedicated to winegrape production globally, the potential for annual C capture and storage in this crop is of interest to mitigate greenhouse gas emissions. In this study, we used destructive sampling to measure C stocks in the woody biomass of 15-year-old Cabernet Sauvignon vines from a vineyard in California’s northern San Joaquin Valley. We characterize C stocks in terms of allometric variation between biomass fractions of roots, aboveground wood, canes, leaves and fruits, and then test correlations between easy-to-measure variables such as trunk diameter, pruning weights and harvest weight to vine biomass fractions. Carbon stocks at the vineyard block scale were validated from biomass mounds generated during vineyard removal.Results
Total vine C was estimated at 12.3 Mg C ha?1, of which 8.9 Mg C ha?1 came from perennial vine biomass. Annual biomass was estimated at 1.7 Mg C ha?1 from leaves and canes and 1.7 Mg C ha?1 from fruit. Strong, positive correlations were found between the diameter of the trunk and overall woody C stocks (R2 = 0.85), pruning weights and leaf and fruit C stocks (R2 = 0.93), and between fruit weight and annual C stocks (R2 = 0.96).Conclusions
Vineyard C partitioning obtained in this study provides detailed C storage estimations in order to understand the spatial and temporal distribution of winegrape C. Allometric equations based on simple and practical biomass and biometric measurements could enable winegrape growers to more easily estimate existing and future C stocks by scaling up from berries and vines to vineyard blocks.353.
Christina R. Ergler Sarah Lovell Alison Watkins Christine Milligan Lee Thompson Daniel J. Exeter Robin Kearns 《New Zealand geographer》2017,73(3):205-217
Health geography in Aotearoa New Zealand (NZ) has had a major impact on international sub‐disciplinary debates. It is timely to celebrate our domestic health geography achievements and alert ourselves to the challenges ahead. This reflection article provides a brief overview of Aotearoa NZ's maturing health geography community and includes the reflections of a panel discussion held during the bi‐annual NZ Geographical Society conference in 2016. We argue that the eclectism of health geography in NZ and beyond is both the sub‐discipline's major strength and challenge. 相似文献
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357.
Trophic structure and pathways of biogenic carbon flow in the eastern North Water Polynya 总被引:1,自引:0,他引:1
Jean-ric Tremblay Hiroshi Hattori Christine Michel Marc Ringuette Zhi-Ping Mei Connie Lovejoy Louis Fortier Keith A. Hobson David Amiel Kirk Cochran 《Progress in Oceanography》2006,71(2-4):402
In the eastern North Water, most of the estimated annual new and net production of carbon (C) occurred during the main diatom bloom in 1998. During the bloom, at least 30% of total and new phytoplankton production occurred as dissolved organic carbon (DOC) and was unavailable for short-term assimilation into the herbivorous food web or sinking export. Based on particle interceptor traps and 234Th deficits, 27% of the particulate primary production (PP) sank out of the upper 50 m, with only 7% and 1% of PP reaching the benthos at shallow (≈200 m) and deep (≈500 m) sites, respectively. Mass balance calculations and grazing estimates agree that ≈79% of PP was ingested by pelagic consumers between April and July. During this period, the vertical flux of biogenic silica (BioSi) at 50 m was equivalent to the total BioSi produced, indicating that all of the diatom production was removed from the euphotic zone as intact cells (direct sinking) or empty frustules (grazing or lysis). The estimated flux of empty frustules was consistent with rates of herbivory by the large, dominant copepods and appendicularians during incubations. Since the carbon demand of the dominant planktivorous bird, Alle alle, amounted to ≈2% of the biomass synthesized by its main prey, the large copepod Calanus hyperboreus, most of the secondary carbon production was available to pelagic carnivores. Stable isotopes indicated that the biomass of predatory amphipods, polar cod and marine mammals was derived from these herbivores, but corresponding carbon fluxes were not quantified. Our analysis shows that a large fraction of PP in the eastern North Water was ingested by consumers in the upper 50 m, leading to substantial carbon respiration and DOC accumulation in surface waters. An increasingly early and prolonged opening of the Artic Ocean is likely to promote the productivity of the herbivorous food web, but not the short-term efficiency of the particulate, biological CO2 pump. 相似文献
358.
Jacek Kozak Christine Estreguil Katarzyna Ostapowicz 《International Journal of Applied Earth Observation and Geoinformation》2008
The aim of the study was to elaborate a methodology for forest mapping based on high resolution satellite data, relevant for reporting on forest cover and spatial pattern changes in Europe. The Carpathians were selected as a case study area and mapped using 24 Landsat scenes, processed independently with a supervised approach combining image segmentation, knowledge-based rules to extract a training set and the maximum likelihood decision rule. Validation was done with available very high resolution imagery. Overall accuracies per scene ranged from 93 to 96%. The labelling disagreement in overlapping areas of adjacent scenes was 6.8% on average. 相似文献
359.
Christine Barwick 《Urban geography》2018,39(6):916-934
Creating social mix in neighborhoods has been an important urban policy during the past years. The aim is the development of category-crossing ties between the middle and lower classes. However, studies found little evidence of such ties. This paper identifies two reasons why this might be the case. First, studies usually analyze the resource flow from native middle classes to disadvantaged residents. Second, the resource flow is analyzed within one neighborhood only. Based on interviews and network analysis with second generation, upwardly mobile Turkish-Germans in Berlin, I show that they act as cultural and language brokers, benefiting lower class co-ethnics. They provide exactly the information and resources to people with a lower class background that are envisioned by social mixing programs. Moreover, the resource flow occurs within but also across neighborhoods, whereby ‘second neighborhoods’ such as the previous neighborhood or the neighborhood where the workplace is located are particularly important. 相似文献
360.