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Sample records for arnhem land northern

  1. Nutrition and health (1948) of Aborigines in settlements in Arnhem Land, northern Australia.

    PubMed

    McArthur, M; Billington, B P; Hodges, K T; Specht, R L

    2000-09-01

    During the American-Australian Scientific Expedition to Arnhem Land in 1948, a nutritionist (Margaret McArthur), a medical officer (Brian Billington), a biochemist (Kelvin Hodges) and also the 'flying dentist' (John Moody) observed the nutrition and health of Aborigines in the settlements on Groote Eylandt, at Yirrkala and at Oenpelli, Northern Territory. The results of their research were published in the Records of the American-Australian Scientific Expedition to Arnhem Land Volume 2 Anthropology and Nutrition. (Melbourne University Press, 1960). Although seasonal and regional variations in food supply were a constant problem for nomadic Aborigines living on 'bush tucker' gathered from marine, freshwater and terrestrial ecosystems, the variety of food provided a well-balanced diet according to the international recommendations of 1948. In contrast, improvements in the 1948 diet of Aborigines in the settlements were strongly recommended. 1 An increase in the quantity of food given to older children and adolescents. 2 Regular distribution of fresh fruit and vegetables throughout the year from settlement gardens. 3 Regular supplies of fish, meat and other animal products, particularly for children, adolescents, pregnant and lactating mothers. 4 Increased production of milk and greater care in its handling. 5 Greater use of whole grain cereals in preference to refined products. PMID:24394450

  2. The Aboriginal Australian in Northern-Eastern Arnhem Land. Resources Review.

    ERIC Educational Resources Information Center

    Maccoll, Peter

    The paper examines the nature of current curriculum and resource materials related to Aboriginal studies, and reviews the curriculum materials "The Aboriginal Australian in North-Eastern Arnhem Land" which were trialled with Year 8 and Year 9 classes during 1980 in four Queensland State High Schools - Kingston, Mackay North, Murgon, and Pimlico.…

  3. Enough! or too much. What is 'excessive' kava use in Arnhem Land?

    PubMed

    Clough, Alan

    2003-03-01

    The objective of the study was to describe parameters for use in monitoring health, social and economic effects of kava use in Arnhem Land Aboriginal communities in the Northern Territory (NT). Kava has been used mainly in eight communities (population > 200), and in smaller associated homeland areas since 1982 with a total population of approximately 6800, using cross-sectional description and comparison using data from three kava-using communities. Interview data combined with health worker assessments were compiled using: (1) a sample (n=136) aged 16-34 years in one community in 2001-02; (2) a sample (n=101) aged 16 years and over in 2000 where physical assessments and biochemical and haematological data were also collected; (3) participant-observation in one community (133 people aged 18 years and over) during 1989-91. Kava, supplied illegally, was still being used in Arnhem Land in 2001-02. In 2000 dermopathy characteristic of heavy use, abnormally low body mass index (BMI), low blood lymphocytes and abnormally high gamma-glutamyl transferase (GGT) occurred more frequently with increased kava use. These acute effects emerge at average consumption levels of from 310-440 g/week of kava powder. When kava users in one community began to consume it at an average of 240-425 g/week from mid-1990, 19% of available cash resources were spent on kava with 11% of cash resources leaving the local community economy. The proportion of men drinking kava reached 70% and women 62% from mid-1990, with 20% of the population spending unprecedented amounts of time (14 + hours/week) in activities where kava was consumed. These parameters may be useful to monitor kava's adverse health, social and economic effects. Their association with increased kava use suggests that approaches to minimizing harm from its abuse may begin fruitfully with controlling supply. PMID:12745358

  4. Diversity of substance use in eastern Arnhem Land (Australia): patterns and recent changes.

    PubMed

    Clough, Alan R; Guyula, Terrence; Yunupingu, Maymuna; Burns, Christopher B

    2002-12-01

    The objective of this study was to describe patterns of substance use among remote Aboriginal community populations. The setting was the eastern Arnhem Land ('Miwatj') region of the Northern Territory's (NT) 'Top End', with a population of 4217 Aboriginal people over 15 years of age using a cross-sectional description and comparison. Sample 1 (n = 689) from the region used data from health-worker consensus classification of kava, alcohol, tobacco, petrol and cannabis use. Sample 2 (n = 101) from one community used self-reported use, age at commencement, duration, amounts consumed and expenditure. In 1999 (sample 1), 46% of males and 18% of females were kava users, alcohol: 53% males, 12% females, tobacco: 68% males, 65% females, and cannabis: 31% males, 8% females. Less than 5% sniffed petrol. In one community in 2000, 39% males and 20% females reported using cannabis during the previous month. In this community between 1999 and 2000, the proportion of current kava users among men declined (77-52%, p = 0.015) with a tendency in women for a decrease in the proportion of tobacco users (87-69%, p = 0.096). The increase in the proportion of cannabis users in men (21-39%, p = 0.068) was not statistically significant. However, in women the increase was significant (0-20%, p = 0.013). Gross expenditure on tobacco and kava were similar in 2000: both greater than cannabis and alcohol. Median years used ranged from 4 years for cannabis and 20 years for tobacco. The data supported anecdotes of a recent rise in cannabis use, especially in women. Kava use declined in men. Tobacco use patterns in women may have been changing. Average per capita consumption of alcohol was low compared with other 'Top End' areas. Such varied and dynamic substance use patterns pose challenges for research and policy. PMID:12537704

  5. Cultural legacies, fire ecology, and environmental change in the Stone Country of Arnhem Land and Kakadu National Park, Australia

    PubMed Central

    Trauernicht, Clay; Murphy, Brett P; Tangalin, Natalia; Bowman, David M J S

    2013-01-01

    We use the fire ecology and biogeographical patterns of Callitris intratropica, a fire-sensitive conifer, and the Asian water buffalo (Bubalus bubalis), an introduced mega-herbivore, to examine the hypothesis that the continuation of Aboriginal burning and cultural integration of buffalo contribute to greater savanna heterogeneity and diversity in central Arnhem Land (CAL) than Kakadu National Park (KNP). The ‘Stone Country’ of the Arnhem Plateau, extending from KNP to CAL, is a globally renowned social–ecological system, managed for millennia by Bininj-Kunwok Aboriginal clans. Regional species declines have been attributed to the cessation of patchy burning by Aborigines. Whereas the KNP Stone Country is a modern wilderness, managed through prescribed burning and buffalo eradication, CAL remains a stronghold for Aboriginal management where buffalo have been culturally integrated. We surveyed the plant community and the presence of buffalo tracks among intact and fire-damaged C. intratropica groves and the savanna matrix in KNP and CAL. Aerial surveys of C. intratropica grove condition were used to examine the composition of savanna vegetation across the Stone Country. The plant community in intact C. intratropica groves had higher stem counts of shrubs and small trees and higher proportions of fire-sensitive plant species than degraded groves and the savanna matrix. A higher proportion of intact C. intratropica groves in CAL therefore indicated greater gamma diversity and habitat heterogeneity than the KNP Stone Country. Interactions among buffalo, fire, and C. intratropica suggested that buffalo also contributed to these patterns. Our results suggest linkages between ecological and cultural integrity at broad spatial scales across a complex landscape. Buffalo may provide a tool for mitigating destructive fires; however, their interactions require further study. Sustainability in the Stone Country depends upon adaptive management that rehabilitates the

  6. Cultural legacies, fire ecology, and environmental change in the Stone Country of Arnhem Land and Kakadu National Park, Australia.

    PubMed

    Trauernicht, Clay; Murphy, Brett P; Tangalin, Natalia; Bowman, David M J S

    2013-02-01

    We use the fire ecology and biogeographical patterns of Callitris intratropica, a fire-sensitive conifer, and the Asian water buffalo (Bubalus bubalis), an introduced mega-herbivore, to examine the hypothesis that the continuation of Aboriginal burning and cultural integration of buffalo contribute to greater savanna heterogeneity and diversity in central Arnhem Land (CAL) than Kakadu National Park (KNP). The 'Stone Country' of the Arnhem Plateau, extending from KNP to CAL, is a globally renowned social-ecological system, managed for millennia by Bininj-Kunwok Aboriginal clans. Regional species declines have been attributed to the cessation of patchy burning by Aborigines. Whereas the KNP Stone Country is a modern wilderness, managed through prescribed burning and buffalo eradication, CAL remains a stronghold for Aboriginal management where buffalo have been culturally integrated. We surveyed the plant community and the presence of buffalo tracks among intact and fire-damaged C. intratropica groves and the savanna matrix in KNP and CAL. Aerial surveys of C. intratropica grove condition were used to examine the composition of savanna vegetation across the Stone Country. The plant community in intact C. intratropica groves had higher stem counts of shrubs and small trees and higher proportions of fire-sensitive plant species than degraded groves and the savanna matrix. A higher proportion of intact C. intratropica groves in CAL therefore indicated greater gamma diversity and habitat heterogeneity than the KNP Stone Country. Interactions among buffalo, fire, and C. intratropica suggested that buffalo also contributed to these patterns. Our results suggest linkages between ecological and cultural integrity at broad spatial scales across a complex landscape. Buffalo may provide a tool for mitigating destructive fires; however, their interactions require further study. Sustainability in the Stone Country depends upon adaptive management that rehabilitates the coupling of

  7. The population ecology of two tropical trees, Brachychiton diversifolius (Malvaceae) and Bombax ceiba (Bombaceae), harvested by Indigenous woodcarvers in Arnhem Land, Australia.

    PubMed

    Koenig, Jennifer; Griffiths, Anthony

    2012-10-01

    We describe the population ecology of two tropical deciduous trees, Bombax ceiba leiocarpum A. Robyns and Brachychiton diversifolius R. Br., which are in high demand for Indigenous sculpture production in Arnhem Land, Australia. We monitored tagged populations of both species at two locations for 2 years to examine their reproduction, growth, and survival rates and their response to harvest. Both species have similar life histories: they reproduce during the dry season (June-November) producing a high seed load, seed predation was high, seeds did not survive in the soil past the following wet season to form a seed bank, and germination rates were low and variable for both species. Average annual circumference growth rates were 1.07 cm year(-1) for B. ceiba and 0.98 cm year(-1) for B. diversifolius, with most of the growth occurring during the early wet season. Most (65-88 %) of the harvested B. ceiba and B. diversifolius stems coppiced. Coppice and stem size class were the main factors influencing tree growth rates with coppice stems growing up to six times faster than similar sized non-coppice stems. The survival of B. ceiba and B. diversifolius stems was size class dependent and affected by local site factors (e.g. fire and other disturbances) so that the smaller size classes had a low probability of survival. Given the resprouting potential of both species, their wild harvest is likely to have only minimal local impact on wild populations. However, further population modelling is required to determine whether the small and disjunct B. ceiba populations can sustain harvesting at current levels. PMID:22829220

  8. Land use of northern megalopolis

    NASA Technical Reports Server (NTRS)

    Simpson, R. B.; Lindgren, D. T.

    1973-01-01

    The major objective is to map and digitize the land use of northern megalopolis, the states of Massachusetts, Connecticut, and Rhode Island, and to evaluate ERTS as a planning tool for megalopolitan areas. The southern New England region provides a good test ERTS's capabilities because of its complex landscape. Not only are there great differences in the degree of urban development, but in relief and vegetative cover as well.

  9. Land scarcity in Northern Namibia

    NASA Astrophysics Data System (ADS)

    Bloemertz, Lena; Dobler, Gregor; Graefe, Olivier; Kuhn, Nikolaus J.; Nghitevelekwa, Romie; Prudat, Brice; Weidmann, Laura

    2015-04-01

    Land access is a major topic in the Namibian population, which can also be seen in political discourses. In North-Central Namibia, the ongoing Communal Land Reform aims at improving tenure security and thereby also hopes to promote sustainable investment in land. Within this context, it is often argued that population growth is leading to an increased scarcity of land. However, this argument falls short of actual issues determining land scarcity in Namibia. In a context, where a large part of the population is still seen as depending on agricultural production, land scarcity has to be measured by different means to assess physical scarcity (population density, farm density, proportion of cultivated areas, or yield per person) as well as the perception of these different scarcities. This paper aims to discuss the different notions of land scarcity and argues that by focusing only on the physical realities of increasing pressure on land because of population growth, important other aspects are neglected. In order to scrutinize those measures, the study will further look at the distribution of different land uses, changing land use practices as connected to changing labour availability and mobility. Special attention will thereby be given to the difference between land scarcity and fertile soil scarcity and their relation to labour availability.

  10. Land use in the northern Coachella Valley

    NASA Technical Reports Server (NTRS)

    Bale, J. B.; Bowden, L. W.

    1973-01-01

    Satellite imagery has proved to have great utility for monitoring land use change and as a data source for regional planning. In California, open space desert resources are under severe pressure to serve as a source for recreational gratification to individuals living in the heavily populated southern coastal plain. Concern for these sensitive arid environments has been expressed by both federal and state agencies. The northern half of the Coachella Valley has historically served as a focal point for weekend recreational activity and second homes. Since demand in this area has remained high, land use change from rural to urban residential has been occurring continuously since 1968. This area of rapid change is an ideal site to illustrate the utility of satellite imagery as a data source for planning information, and has served as the areal focus of this investigation.

  11. Combining Aboriginal and Non-Aboriginal Knowledge to Assess and Manage Feral Water Buffalo Impacts on Perennial Freshwater Springs of the Aboriginal-Owned Arnhem Plateau, Australia

    NASA Astrophysics Data System (ADS)

    Ens, Emilie-Jane; Cooke, Peter; Nadjamerrek, Ray; Namundja, Seraine; Garlngarr, Victor; Yibarbuk, Dean

    2010-04-01

    Aboriginal land managers have observed that feral Asian water buffalo ( Bubalis bubalis Lydekker) are threatening the ecological and cultural integrity of perennial freshwater sources in Arnhem Land, Australia. Here we present collaborative research between the Aboriginal Rangers from Warddeken Land Management Limited and Western scientists which quantified the ground-level impacts of buffalo on seven perennial freshwater springs of the Arnhem Plateau. A secondary aim was to build the capacity of Aboriginal Rangers to self-monitor and evaluate the ecological outcomes of their land management activities. Sites with high buffalo abundance had significantly different ground, ground cover, and water quality attributes compared to sites with low buffalo abundance. The low buffalo abundance sites were characterized by tall herbaceous vegetation and flat ground, whereas wallows, bare ground, and short ungrazed grasses were indicators of sites with high buffalo abundance. Water turbidity was greater when buffalo abundance was high. The newly acquired monitoring skills and derived indicators of buffalo damage will be used by Aboriginal Rangers to assess the ecological outcomes of their future buffalo control efforts on the Arnhem Plateau.

  12. Land use of northern megalopolis from ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Simpson, R. B. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. A color-coded urban-type land use map of the three northern megalopolitan states of Massachusetts, Connecticut, and Rhode Island has been completed from ERTS-1 images. A computer data bank containing 11 categories of land use for the entire area by 1/4-square-kilometer cells is 80% completed. When completed, the data bank will permit the investigation to proceed to brief analytical studies for completion of the study.

  13. Changes of Land Cover and Land Use and Greenhouse Gas Emissions in Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Zhuang, Q.; Melillo, J.; Reilly, J.; McGuire, A.; Prinn, R.; Shvidenko, A.; Tchebakova, N.; Sirin, A.; Maksyutov, S.; Peregon, A.

    2009-04-01

    Northern Eurasia accounts for about 20% of the Earth's land surface and 60% of the terrestrial land cover north of 40°N. It contains 70% of the Earth's boreal forests and more than two-thirds of the Earth's land that is underlain by permafrost. The region is covered by vast areas of peatland, complex tundra in the north and semi-deserts and deserts in the south, including the Mongolia plateau. The surface air temperature has increased in the last half century and this increase will continue during this century. We present the results of climate change effects on biogeochemical processes and mechanisms governing the carbon and water dynamics in the region. Future research will address on how patterns of land use in Northern Eurasia may change in the future due to: 1) Economic pressures for providing food, fiber and fuel to a growing global population; 2) Expansion of management of land for cropping, pasture, and forestry into areas that experience a more favorable climate in the future; and 3) Abandonment of management in areas that experience a less favorable climate and the implications of these changes for (1) the exchange of CO2 and CH4 between terrestrial ecosystems and the atmosphere; (2) terrestrial carbon storage and primary productivity; (3) water supply; and (4) radiative forcing of the atmosphere through changes in surface albedo. We use a system of linked models that include the MIT Emissions Prediction and Policy Analysis (EPPA) model of the world economy, the SiBCliM bioclimatic vegetation model, and the Terrestrial Ecosystem Model (TEM) with land-cover/ land-use modeling and biogeochemical modeling based on current relationships as observed through satellite and remote sensing data.

  14. Land management versus natural factors in land instability: some examples in northern Spain.

    PubMed

    Bruschi, Viola Maria; Bonachea, Jaime; Remondo, Juan; Gómez-Arozamena, Jose; Rivas, Victoria; Barbieri, Matteo; Capocchi, Stefano; Soldati, Mauro; Cendrero, Antonio

    2013-08-01

    The objective of this work is to test a hypothesis formulated on the basis of former results which considers that there might be a ‘‘global geomorphic change,’’ due to activities related to land management and not determined by climate change, which could be causing an acceleration of geomorphic processes. Possible relationships between some geomorphic processes related to land instability (landslides or sediment generation) and potential triggering factors are analyzed in study areas in northern Spain. The analysis is based on landslide inventories covering different periods, as well as the determination of sedimentation rates. Temporal landslide and sedimentation rate trends are compared with different indicators of human activities (land-use change, logging, forest fires) and with potential natural triggers (rainfall, seismicity). The possible influence of the road network in the distribution of landslides is also analyzed. Results obtained show that there is a general increase of both landslide and sedimentation rates with time that cannot be explained satisfactorily by observed rainfall trends and even less by seismicity. Land use change appears to be by far the main factor leading to land instability, with some changes producing up to a 12-fold increase of landslide rate. A relationship between road network and the spatial distribution of landslides has also been observed. These results do confirm the existence of an acceleration of geomorphic processes in the region, and also suggest that climate-related factors play a limited role in the changes observed. PMID:23797484

  15. Late Quaternary land-sea correlations, northern Labrador, Canada

    SciTech Connect

    Clark, P.; Josenhans, H.

    1985-01-01

    Late Quaternary glacial and postglacial units in the Torngat Mountains, northern Labrador, are correlated with units identified on the adjacent continental shelf. The late Wisconsinan Laurentide Ice Sheet drained through major valleys of the Torngat Mountains as outlet glaciers, depositing the Saglek Moraines. These are of regional extent and have been mapped from Saglek Fiord north to Noodleook Fiord. A C-14 date of 18,210 +/- 1900 BP on total organic matter (TOM) from lake sediment dammed by a segment of the Saglek Moraines is interpreted as a maximum date for deposition of the Saglek Moraine system because of possible contamination. Glacial sediments comprising the Saglek Moraines are correlated with upper till mapped in troughs and saddles on the continental shelf. Outlet glaciers depositing a late Wisconsinan unit flowed through Labrador fiords and onto the shelf at low basal shear stresses, particularly on the shelf where, although grounded, they were hydrostatically buoyed up and moved principally by sliding. A glaciomarine unit conformably overlies late Wisconsinan till on the shelf and on the land. This unit is a gravelly clayey silt, contains abundant foraminifera, and has up to 60% limestone in the pebble fraction. C-14 dates suggest deposition of this unit began ca. 10,000 BP on the shelf and 9000 BP on the land, an ended by 8000 BP. Limestone pebbles in this unit suggest a source in part from sediment-laden icebergs and pack-ice from the north. Marine deposition from ca. 8000-0 BP is characterize by basinal sedimentation.

  16. Contribution of the NASA Land-Cover/Land-Use Change (LCLUC) Program to the Northern Eurasia Partnership Initiative (NEESPI)

    NASA Astrophysics Data System (ADS)

    Gutman, G.

    2004-12-01

    Northern Eurasia - a geographic area, which includes the territory of the Former Soviet Union, northern China and Mongolia, Scandinavia and Eastern Europe - has recently become a study area of an international, interagency program NEESPI (Northern Eurasia Partnership Initiative, http://neespi.gsfc.nasa.gov). NASA is currently the NEESPI major partner, with several NASA programs contributing to this initiative. Among them is the Land-Cover/Land-Use Change (LCLUC) Program. This talk will discuss the LCLUC Program contribution to the NEESPI, in particular the start-up projects on Carbon Cycle science studies. The area of Northern Eurasia plays a major role in the global carbon budget merely due to its vast territory covered by the boreal forests and peat lands. Also, climate warming is most pronounced in this geographic area with temperature rise expected to be the greatest over the globe. This, in turn, induces natural terrestrial processes, especially in permafrost areas, to release more carbon dioxide and methane into the atmosphere. As far as the LCLUC processes are concerned, northern Eurasia is specifically interesting due to the dramatic socio-economic shifts throughout this region during the last decade. The rapid land use changes create the possibility for large and significant biological and climatic feedbacks in this region that could be of global importance. Regionally, significant changes in land use coupled with climate change may affect various sectors, including forestry, costal zone and agricultural systems. Additionally, these processes may have direct impacts on the society, including human health issues. This talk will present the use of NASA remote sensing data in reducing uncertainties in regional carbon budget estimates in studies of northern Eurasia. Current and planned research on detection, monitoring and impacts of changes in land cover and land use in northern Eurasia will be discussed. http://lcluc.gsfc.nasa.gov

  17. Mosquito Larval Habitats, Land Use, and Potential Malaria Risk in Northern Belize from Satellite Image Analyses

    NASA Technical Reports Server (NTRS)

    Pope, Kevin; Masuoka, Penny; Rejmankova, Eliska; Grieco, John; Johnson, Sarah; Roberts, Donald

    2004-01-01

    The distribution of Anopheles mosquito habitats and land use in northern Belize is examined with satellite data. -A land cover classification based on multispectral SPOT and multitemporal Radarsat images identified eleven land cover classes, including agricultural, forest, and marsh types. Two of the land cover types, Typha domingensis marsh and flooded forest, are Anopheles vestitipennis larval habitats. Eleocharis spp. marsh is the larval habitat for Anopheles albimanus. Geographic Information Systems (GIS) analyses of land cover demonstrate that the amount of T-ha domingensis in a marsh is positively correlated with the amount of agricultural land in the adjacent upland, and negatively correlated with the amount of adjacent forest. This finding is consistent with the hypothesis that nutrient (phosphorus) runoff from agricultural lands is causing an expansion of Typha domingensis in northern Belize. This expansion of Anopheles vestitipennis larval habitat may in turn cause an increase in malaria risk in the region.

  18. Land Surface Data Assimilation and the Northern Gulf Coast Land/Sea Breeze

    NASA Technical Reports Server (NTRS)

    Lapenta, William M.; Blackwell, Keith; Suggs, Ron; McNider, Richard T.; Jedlovec, Gary; Kimball, Sytske; Arnold, James E. (Technical Monitor)

    2002-01-01

    A technique has been developed for assimilating GOES-derived skin temperature tendencies and insolation into the surface energy budget equation of a mesoscale model so that the simulated rate of temperature change closely agrees with the satellite observations. A critical assumption of the technique is that the availability of moisture (either from the soil or vegetation) is the least known term in the model's surface energy budget. Therefore, the simulated latent heat flux, which is a function of surface moisture availability, is adjusted based upon differences between the modeled and satellite observed skin temperature tendencies. An advantage of this technique is that satellite temperature tendencies are assimilated in an energetically consistent manner that avoids energy imbalances and surface stability problems that arise from direct assimilation of surface shelter temperatures. The fact that the rate of change of the satellite skin temperature is used rather than the absolute temperature means that sensor calibration is not as critical. The sea/land breeze is a well-documented mesoscale circulation that affects many coastal areas of the world including the northern Gulf Coast of the United States. The focus of this paper is to examine how the satellite assimilation technique impacts the simulation of a sea breeze circulation observed along the Mississippi/Alabama coast in the spring of 2001. The technique is implemented within the PSU/NCAR MM5 V3-4 and applied on a 4-km domain for this particular application. It is recognized that a 4-km grid spacing is too coarse to explicitly resolve the detailed, mesoscale structure of sea breezes. Nevertheless, the model can forecast certain characteristics of the observed sea breeze including a thermally direct circulation that results from differential low-level heating across the land-sea interface. Our intent is to determine the sensitivity of the circulation to the differential land surface forcing produced via the

  19. Land use of northern megalopolis from ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Simpson, R. B. (Principal Investigator)

    1972-01-01

    The author has identified the following significant results. The preliminary map of land use of Rhode Island is believed to be the first urban-type land use map ever made from satellite imagery, and its preparation a significant scientific result for ERTS-1. Eight categories of land use were differentiated at a scale of 1:250,000 including 3 categories of residential area: single family and multiple/mixed urban types, plus a residential and open space rural one. This compares favorably with RB-57 mapping experience in which, mapping at 1:120,000 from photography taken from 60,000 feet, 11 basic categories of land use were discriminated. From ERTS, the urban cores of cities down to 7,000 population, and commercial and industrial sites down to 800 feet square, were consistently discriminated.

  20. Investigation of land use of northern megalopolis using ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Simpson, R. B.; Lindgren, D. T.; Ruml, D. J.; Goldstein, W.

    1974-01-01

    Primary objective was to produce a color-coded land use map and digital data base for the northern third of Megalopolis. Secondary objective was to investigate possible applications of ERTS products to land use planning. Many of the materials in this report already have received national, dissemination as a result of unexpected interest in land use surveys from ERTS. Of special historical interest is the first comprehensive urban-type land use map from space imagery, which covered the entire state of Rhode Island and was made from a single image taken on 28 July 1972.

  1. Combined analysis of land cover change and NDVI trends in the Northern Eurasian grain belt

    NASA Astrophysics Data System (ADS)

    Wright, Christopher K.; de Beurs, Kirsten M.; Henebry, Geoffrey M.

    2012-06-01

    We present an approach to regional environmental monitoring in the Northern Eurasian grain belt combining time series analysis of MODIS normalized difference vegetation index (NDVI) data over the period 2001-2008 and land cover change (LCC) analysis of the 2001 and 2008 MODIS Global Land Cover product (MCD12Q1). NDVI trends were overwhelmingly negative across the grain belt with statistically significant ( p⩽0.05) positive trends covering only 1% of the land surface. LCC was dominated by transitions between three classes; cropland, grassland, and a mixed cropland/natural vegetation mosaic. Combining our analyses of NDVI trends and LCC, we found a pattern of agricultural abandonment (cropland to grassland) in the southern range of the grain belt coinciding with statistically significant ( p⩽0.05) negative NDVI trends and likely driven by regional drought. In the northern range of the grain belt we found an opposite tendency toward agricultural intensification; in this case, represented by LCC from cropland mosaic to pure cropland, and also associated with statistically significant ( p⩽0.05) negative NDVI trends. Relatively small clusters of statistically significant ( p⩽0.05) positive NDVI trends corresponding with both localized land abandonment and localized agricultural intensification show that land use decision making is not uniform across the region. Land surface change in the Northern Eurasian grain belt is part of a larger pattern of land cover land use change (LCLUC) in Eastern Europe, Russia, and former territories of the Soviet Union following realignment of socialist land tenure and agricultural markets. Here, we show that a combined analysis of LCC and NDVI trends provides a more complete picture of the complexities of LCLUC in the Northern Eurasian grain belt, involving both broader climatic forcing, and narrower anthropogenic impacts, than might be obtained from either analysis alone.

  2. Land Cover of Northern Eurasia: Comparison and Assessment of Coarse Resolution Maps

    NASA Astrophysics Data System (ADS)

    Krankina, O. N.; Pflugmacher, D.; Cohen, W.; Kennedy, R.; Nelson, P.; Loboda, T.

    2007-12-01

    Consistent measurements of land cover are critical for addressing a range of important science questions, from quantifying the effects of vegetation on the carbon, energy, and water cycles, to understanding the social and economic causes and consequences of land-use and land-cover change. While multiple moderate and coarse- resolution land-cover products have been developed, they disagree significantly. Resolving discrepancies among maps is particularly challenging for boreal and temperate Northern Eurasia, where validation sites are sparse and processes of ecosystem disturbance and land-cover change are widespread. To identify specific needs and possibilities for improved mapping of land cover across boreal and temperate Northern Eurasia, we compared the performance of three recent land-cover products based on different sensors: MODIS (Global Land Cover Collection 4), AVHRR (DISCover v. 2.0), and SPOT VEGETATION (GLC2000 for Northern Eurasia v. 4.0). First, we examined the level of agreement among these data sets across the entire region. On a qualitative level, the assessment of general patterns indicates the highest degree of disagreement in transitional zones at the northern and southern fringes of boreal forest, in mountainous regions, and in areas of extensive wetlands, agricultural development, and urban land use. The quantitative analysis measured the level of disagreement between land-cover classes aggregated according to dominant type of vegetation (trees, shrubs, herbaceous, bare land, permanent snow/ice). Secondly, validation of these products was performed at two test sites where Landsat-based classifications were developed based on FAO Land Cover Classification System. Fractional land cover was calculated for each 1x1 km pixel and used to construct fractional error matrices. Most errors were associated with "mixed" coarse-resolution pixels (i.e. those having nearly equal percentage of multiple class types), while errors in "pure" (single class) pixels

  3. Importance of Nitrogen Availability on Land Carbon Sequestration in Northern Eurasia during the 21st Century

    NASA Astrophysics Data System (ADS)

    Kicklighter, D. W.; Melillo, J. M.; Monier, E.; Sokolov, A. P.; Lu, X.; Zhuang, Q.

    2015-12-01

    Atmospheric nitrogen deposition, nitrogen fixation, and the application of nitrogen fertilizers provide subsidies to land ecosystems that can increase nitrogen availability for vegetation production and thereby influence land carbon dynamics. In addition, enhanced decomposition of soil organic matter (SOM) from warming soils and permafrost degradation may also increase nitrogen availability in Northern Eurasia. Here, we examine how changes in nitrogen availability may influence land carbon dynamics in Northern Eurasia during the 21st century by comparing results for a "business as usual" scenario (the IPCC Representative Concentration Pathways or RCP 8.5) and a stabilization scenario (RCP 4.5) between a version of the Terrestrial Ecosystem Model that does not consider the effects of atmospheric nitrogen deposition, nitrogen fixation and soil thermal dynamics on land carbon dynamics (TEM 4.4) and a version that does consider these dynamics (TEM 6.0). In these simulations, atmospheric nitrogen deposition, nitrogen fixation, and fertilizer applications provide an additional 3.3 Pg N (RCP 4.5) to 3.9 Pg N (RCP 8.5) to Northern Eurasian ecosystems over the 21st century. Land ecosystems retain about 38% (RCP4.5) to 48% (RCP 8.5) of this nitrogen subsidy. Net nitrogen mineralization estimated by TEM 6.0 provide an additional 1.0 Pg N to vegetation than estimated by TEM 4.4 over the 21st century from enhanced decomposition of SOM including SOM formerly protected by permafrost. The enhanced nitrogen availability in TEM 6.0 allows Northern Eurasian ecosystems to sequester 1.8x (RCP 8.5) to 2.4x (RCP 4.5) more carbon over the 21st century than estimated by TEM 4.4. Our results indicate that consideration of nitrogen subsidies and soil thermal dynamics have a large influence on how simulated land carbon dynamics in Northern Eurasia will respond to future changes in climate, atmospheric chemistry, and disturbances.

  4. Habitat use and movement patterns of Northern Pintails during spring in northern Japan: the importance of agricultural lands

    USGS Publications Warehouse

    Yamaguchi, Noriyuki M.; Hupp, Jerry W.; Flint, Paul L.; Pearce, John M.; Shigeta, Yusuke; Shimada, Tetsuo; Hiraoka, Emiko N.; Higuchi, Hiroyoshi

    2012-01-01

    From 2006 to 2009, we marked 198 Northern Pintails (Anas acuta) with satellite transmitters on their wintering areas in Japan to study their migration routes and habitat use in spring staging areas. We hypothesized that the distribution of pintails during spring staging was influenced by patterns of land use and expected that the most frequently used areas would have more agricultural habitat than lesser-used areas. We obtained 3031 daily locations from 163 migrant pintails marked with satellite transmitters and identified 524 stopover sites. Based on a fixed kernel home range analysis of stopover utilization distribution (UD), core staging areas (areas within the 50% UD) were identified in northern Honshu and western Hokkaido, and were used by 71% of marked pintails. Core staging areas had a greater proportion of rice fields than peripheral (51–95% UD) and rarely used (outside the 95% UD) staging areas. Stopover sites also contained more rice fields and other agricultural land than were available at regional scales, indicating that pintails selected rice and other agricultural habitats at regional and local scales. Pintails remained at spring staging areas an average of 51 d. Prolonged staging in agricultural habitats of northern Japan was likely necessary for pintails to prepare for transoceanic migration to Arctic nesting areas in eastern Russia.

  5. Evidence for Wind-Driven Rain Erosion on Sunflower Stubble Land in the Northern Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-crop production systems in the northern Great Plains have undergone species diversification to include those with non-durable residues. To assess hazards when lands with such crops are tilled or fallowed, a wind erosion study was established in central North Dakota on silt loam soil (Haplustoll...

  6. A New Strategy to Land Precisely on the Northern Plains of Mars

    NASA Technical Reports Server (NTRS)

    Cheng, Yang; Huertas, Andres

    2010-01-01

    During the Phoenix mission landing site selection process, the Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) images revealed widely spread and dense rock fields in the northern plains. Automatic rock mapping and subsequent statistical analyses showed 30-90% CFA (cumulative fractional area) covered by rocks larger than 1 meter in dense rock fields around craters. Less dense rock fields had 5-30% rock coverage in terrain away from craters. Detectable meter-scale boulders were found nearly everywhere. These rocks present a risk to spacecraft safety during landing. However, they are the most salient topographic features in this region, and can be good landmarks for spacecraft localization during landing. In this paper we present a novel strategy that uses abundance of rocks in northern plains for spacecraft localization. The paper discusses this approach in three sections: a rock-based landmark terrain relative navigation (TRN) algorithm; the TRN algorithm feasibility; and conclusions.

  7. USGS Historical, Current, and Projected Future Land Cover Mapping for the Northern Great Plains

    NASA Astrophysics Data System (ADS)

    Sohl, T. L.; Gallant, A.; Sayler, K. L.

    2008-12-01

    Land cover in the Northern Great Plains has changed considerably in the last several decades. While a significant proportion of the landscape has been cultivated for over one hundred years, the intensity of cultivation, crop type, and management practices have changed in response to shifts in government policy, commodity prices, access to water, and technological advances. Changes in land cover impact a wide variety of ecosystem processes and services, including carbon balances, climate, hydrology and water quality, and biodiversity. A consistent record of historical land cover is required to understand relations between land- cover change and these ecological processes, while projections of future land cover are needed for planning and potential mitigation efforts. Several U.S. Geological Survey efforts have been completed or are ongoing in the Northern Great Plains, resulting in the compilation of an unmatched record of historical, current, and future land-cover information for the region. The USGS Land Cover Trends project is using the historical record of Landsat imagery and a robust sampling approach to examine the rates, causes, and consequences of contemporary (1973-2000) land-cover change on an ecoregional basis for the conterminous United States. Results from completed Trends analyses for Great Plains ecoregions revealed changes in the proportion and distribution of grassland/shrubland and agricultural uses during the study period; Some areas exhibited considerable loss in cultivated land after initiation of the Conservation Reserve Program (CRP) in the mid 1980s. In recent years (post-2000), agricultural commodity prices have skyrocketed as food and energy compete for use of agricultural products, which in conjunction with the expiration of many CRP contracts, has led to expansion of cultivated land. In the coming decades, calls for U.S. energy independence and the development of biofuels from cellulosic stock could result in a transformation of the Great

  8. Franz Josef Land: extreme northern outpost for Arctic fishes

    PubMed Central

    Chernova, Natalia V.; Turchik, Alan; Sala, Enric

    2014-01-01

    The remote Franz Josef Land (FJL) Archipelago is the most northerly land in Eurasia and its fish fauna, particularly in nearshore habitats, has been poorly studied. An interdisciplinary expedition to FJL in summer 2013 used scuba, seines, and plankton nets to comprehensively study the nearshore fish fauna of the archipelago. We present some of the first underwater images for many of these species in their natural habitats. In addition, deep water drop cameras were deployed between 32 and 392 m to document the fish fauna and their associated habitats at deeper depths. Due to its high latitude (79°–82°N), extensive ice cover, and low water temperatures (<0 °C much of the year), the fish diversity at FJL is low compared to other areas of the Barents Sea. Sixteen species of fishes from seven families were documented on the expedition, including two species previously unknown to the region. One Greenland shark, Somniosus microcephalus (Somniosidae), ca. 2 m in length, was recorded by drop camera near Hayes Island at 211 m, and Esipov’s pout, Gymnelus esipovi (Zoarcidae), was collected at Wilton Island at 15 m in a kelp forest. Including the tape-body pout, Gymnelus taeniatus, described earlier from the sub-littoral zone of Kuhn Island, 17 fish species are now known from FJL’s nearshore waters. Species endemic to the Arctic accounted for 75% of the nearshore species observed, followed by species with wider ranges. A total of 43 species from 15 families are known from FJL with the majority of the records from offshore trawl surveys between 110 and 620 m. Resident species have mainly high Arctic distributions, while transient species visit the archipelago to feed (e.g., Greenland shark), and others are brought by currents as larvae and later migrate to spawn grounds in the south (e.g., Atlantic cod Gadus morhua, Capelin Mallotus villosus, Beaked redfish Sebastes mentella). Another species group includes warmer-water fishes that are rare waifs (e.g., Glacier

  9. Potential Influence of Climate-Induced Vegetation Shifts on Future Land Use and Associated Land Carbon Fluxes in Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Kicklighter, D. W.; Cai, Y.; Zhuang, Q.; Parfenova, E. I.; Paltsev, S.; Sokolov, A. P.; Melillo, J. M.; Reilly, J. M.; Tchebakova, N. M.; Lu, X.

    2014-12-01

    Climate change will alter ecosystem metabolism and may lead to a redistribution of vegetation and changes in fire regimes in Northern Eurasia over the 21st century. Land management decisions will interact with these climate-driven changes to reshape the region's landscape. Here we present an assessment of the potential consequences of climate change on land use and associated land carbon sink activity for Northern Eurasia in the context of climate-induced vegetation shifts. Under a 'business-as-usual' scenario, climate-induced vegetation shifts allow expansion of areas devoted to food crop production (15%) and pastures (39%) over the 21st century. Under a climate stabilization scenario, climate-induced vegetation shifts permit expansion of areas devoted to cellulosic biofuel production (25%) and pastures (21%), but reduce the expansion of areas devoted to food crop production by 10%. In both climate scenarios, vegetation shifts further reduce the areas devoted to timber production by 6-8% over this same time period. Fire associated with climate-induced vegetation shifts causes the region to become more of a carbon source than if no vegetation shifts occur. Consideration of the interactions between climate-induced vegetation shifts and human activities through a modeling framework has provided clues to how humans may be able to adapt to a changing world and identified the tradeoffs, including unintended consequences, associated with proposed climate/energy policies.

  10. Estimation of Surface Air Temperature from MODIS 1km Resolution Land Surface Temperature Over Northern China

    NASA Technical Reports Server (NTRS)

    Shen, Suhung; Leptoukh, Gregory G.; Gerasimov, Irina

    2010-01-01

    Surface air temperature is a critical variable to describe the energy and water cycle of the Earth-atmosphere system and is a key input element for hydrology and land surface models. It is a very important variable in agricultural applications and climate change studies. This is a preliminary study to examine statistical relationships between ground meteorological station measured surface daily maximum/minimum air temperature and satellite remotely sensed land surface temperature from MODIS over the dry and semiarid regions of northern China. Studies were conducted for both MODIS-Terra and MODIS-Aqua by using year 2009 data. Results indicate that the relationships between surface air temperature and remotely sensed land surface temperature are statistically significant. The relationships between the maximum air temperature and daytime land surface temperature depends significantly on land surface types and vegetation index, but the minimum air temperature and nighttime land surface temperature has little dependence on the surface conditions. Based on linear regression relationship between surface air temperature and MODIS land surface temperature, surface maximum and minimum air temperatures are estimated from 1km MODIS land surface temperature under clear sky conditions. The statistical errors (sigma) of the estimated daily maximum (minimum) air temperature is about 3.8 C(3.7 C).

  11. [Spatiotemporal dynamics of land cover in northern Tibetan Plateau with responses to climate change].

    PubMed

    Song, Chun-qiao; You, Song-cai; Ke, Ling-hong; Liu, Gao-huan; Zhong, Xin-ke

    2011-08-01

    By using the 2001-2008 MOMS land cover products (MCDl2Ql) and based on the modified classification scheme embodied the characteristics of land cover in northern Tibetan Plateau, the annual land cover type maps of the Plateau were drawn, with the dynamic changes of each land cover type analyzed by classification statistics, dynamic transfer matrix, and landscape pattern indices. In 2001-2008, due to the acceleration of global climate warming, the areas of glacier and snow-covered land in the Plateau decreased rapidly, and the melted snow water gathered into low-lying valley or basin, making the lake level raised and the lake area enlarged. Some permanent wetlands were formed because of partially submersed grassland. The vegetation cover did not show any evident meliorated or degraded trend. From 2001 to 2004, as the climate became warmer and wetter, the spatial distribution of desert began to shrink, and the proportions of sparse grassland and grassland increased. From 2006 to 2007, due to the warmer and drier climate, the desert bare land increased, and the sparse grassland decreased. From 2001 to 2008, both the landscape fragmentation degree and the land cover heterogeneity decreased, and the differences in the proportions of all land cover types somewhat enlarged. PMID:22097372

  12. The Cambrian Ross Orogeny in northern Victoria Land (Antarctica) and New Zealand: A synthesis

    USGS Publications Warehouse

    Federico, L.; Capponi, G.; Crispini, L.; Bradshaw, J.D.

    2007-01-01

    In the Cambrian, the paleo-Pacific margin of the Gondwana supercontinent included East Antarctica, Australia, Tasmania and New Zealand and was affected by themajor Ross-Delamerian Orogeny. In Antarctica, evidence suggests that this resulted from oblique subduction and that in northern Victoria Land it was accompanied by the opening and subsequent closure of a back-arc basin. Comparison of the type and timing of sedimentary, magmatic and metamorphic events in areas noted above shows strong similarities between northern Victoria Land and New Zealand. In both regions Middle Cambrian volcanites are interpreted as arc/back-arc assemblages produced by west-directed subduction; sediments interbedded with the volcanites show provenance both from the arc and from the Gondwana margin and therefore place the basin close to the continent. Back-arc closure in the Late Cambrian was likely accomplished through a second subduction system

  13. Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains

    NASA Astrophysics Data System (ADS)

    Graw, Jordan H.; Adams, Aubreya N.; Hansen, Samantha E.; Wiens, Douglas A.; Hackworth, Lauren; Park, Yongcheol

    2016-09-01

    The Transantarctic Mountains (TAMs) are the largest non-compressional mountain range on Earth, and while a variety of uplift mechanisms have been proposed, the origin of the TAMs is still a matter of great debate. Most previous seismic investigations of the TAMs have focused on a central portion of the mountain range, near Ross Island, providing little along-strike constraint on the upper mantle structure, which is needed to better assess competing uplift models. Using data recorded by the recently deployed Transantarctic Mountains Northern Network, as well as data from the Transantarctic Mountains Seismic Experiment and from five stations operated by the Korea Polar Research Institute, we investigate the upper mantle structure beneath a previously unexplored portion of the mountain range. Rayleigh wave phase velocities are calculated using a two-plane wave approximation and are inverted for shear wave velocity structure. Our model shows a low velocity zone (LVZ; ∼4.24 km s-1) at ∼160 km depth offshore and adjacent to Mt. Melbourne. This LVZ extends inland and vertically upwards, with more lateral coverage above ∼100 km depth beneath the northern TAMs and Victoria Land. A prominent LVZ (∼4.16-4.24 km s-1) also exists at ∼150 km depth beneath Ross Island, which agrees with previous results in the TAMs near the McMurdo Dry Valleys, and relatively slow velocities (∼4.24-4.32 km s-1) along the Terror Rift connect the low velocity anomalies. We propose that the LVZs reflect rift-related decompression melting and provide thermally buoyant support for the TAMs uplift, consistent with proposed flexural models. We also suggest that heating, and hence uplift, along the mountain front is not uniform and that the shallower LVZ beneath northern Victoria Land provides greater thermal support, leading to higher bedrock topography in the northern TAMs. Young (0-15 Ma) volcanic rocks associated with the Hallett and the Erebus Volcanic Provinces are situated directly

  14. Pervasive, tholeiitic refertilisation and heterogeneous metasomatism in Northern Victoria Land lithospheric mantle (Antarctica)

    NASA Astrophysics Data System (ADS)

    Pelorosso, Beatrice; Bonadiman, Costanza; Coltorti, Massimo; Faccini, Barbara; Melchiorre, Massimiliano; Ntaflos, Theodoros; Gregoire, Michel

    2016-04-01

    The petrology of peridotite xenoliths in the Cenozoic volcanics from Greene Point (Northern Victoria Land, Antarctica) provides new constraints on the characterisation of the lithospheric mantle beneath the West Antarctic Rift. Based on mineral major and trace element models, this mantle domain is proposed to represent a residuum after 10% and 20% partial melting. Moreover, melting models and isotopic results for Sr and Nd systematics highlight the substantial contribution of tholeiitic melts percolating through peridotites. Close correlation with trace element contents in clinopyroxene phenocrysts from Ferrar and Karoo tholeiites allows us to ascribe this refertilisation event to the Jurassic. This asthenospheric melt was also able to transfer a garnet signature to the Northern Victoria Land mantle segment. The rare presence of glass and secondary phases indicate that Greene Point xenoliths were heterogeneously affected by alkaline metasomatism, probably related to the West Antarctic Rift System opening; this has also been widely observed in other Northern Victoria Land localities (i.e., Baker Rocks). Temperature and fO2 were calculated (950 °C; Δlog fO2 (QFM), - 1.70 to - 0.39) at a fixed pressure of 15 kbar, confirming the tendency of the anhydrous Greene Point xenolith population to have higher equilibration temperatures and comparable redox conditions, compared to the nearby amphibole-bearing peridotites from Baker Rocks.

  15. LAND STREAMER SEISMIC DATA FROM NORTHERN DELAWARE: A VIABLE ALTERNATIVE FOR IMAGING AQUIFERS IN SUBURBAN AREAS

    NASA Astrophysics Data System (ADS)

    Velez, C. C.; McLaughlin, P. P.; McGeary, S. E.; Sargent, S. L.

    2009-12-01

    The Potomac Formation includes the most important confined aquifers in the Coastal Plain of northern Delaware. Development and a growing suburban population are increasing demand for groundwater in the area, making accurate assessment of groundwater water supply increasingly important. Previous studies of subsurface geology indicate that the Potomac Formation is characterized by laterally discontinuous fluvial sand bodies, making it difficult to precisely delineate the distribution and geometry of the aquifer facies based on well correlations alone. A 20-km high-resolution seismic reflection dataset was collected using a land-streamer system in 2008 to constrain subsurface stratigraphy between disparate well locations. The data were collected along roadways in an area of mixed development that includes suburban housing tracts, farmlands, and large industry. A 152-m-deep continuous-cored test hole was drilled in the summer of 2009 adjacent to one of the lines and a full suite of borehole geophysical logs obtained. The land-streamer data are compared to a 3-km dataset collected also in 2008 using conventional methods on farmland in the northern part of the study area. The land streamer system proved to be more effective than conventional seismic reflection methods in this area. Several advantages are evident for the land streamer: 1) overall, the conventional dataset has a higher S/N, 2) on average, collecting data with the land streamer system is four times faster, and 3) the land streamer lines can be longer and therefore more continuous than the conventional lines in a developed area. The land-streamer system has minor disadvantages: traffic control, traffic noise, and in some cases a need for larger crews. Regardless, the land streamer dataset is easier to process, of higher quality, and more cost effective. The final depth images from the land streamer data indicate that the minimum and maximum depths imaged are ~18 m and ~ 268m, with a resolution of ~4 m. This

  16. Implications of land use change in tropical Northern Africa under global warming

    NASA Astrophysics Data System (ADS)

    Brücher, T.; Claussen, M.; Raddatz, T.

    2015-06-01

    A major link between climate and humans in Northern Africa, and the Sahel in particular, is land use and associated land cover change, mainly where subsistence farming prevails. Here we assess possible feedbacks between the type of land use and harvest intensity and climate by analyzing a series of idealized GCM experiments using the MPI-ESM. The base line for these experiments is a simulation forced by the RCP8.5 scenario which includes strong greenhouse gas emissions and anthropogenic land cover changes. The anthropogenic land cover changes in the RCP8.5 scenario include a mixture of pasture and agriculture. In subsequent simulations, we replace the entire area affected by anthropogenic land cover change in the region between the Sahara in the North and the Guinean Coast in the South (4 to 20° N) by either pasture or agriculture, respectively. In a second setup we vary the amount of harvest in case of agriculture. The RCP8.5 base line simulation reveals strong changes in mean agriculture and monsoon rainfall. In comparison with these changes, any variation of the type of land use in the study area leads to very small, mostly insignificantly small, additional differences in mean temperature and annual precipitation change in this region. Within the uncertainty of the representation of land use in current ESMs, our study suggests marginal feedback between land use changes and climate changes triggered by strong greenhouse gas emissions. Hence as a good approximation, climate change can be considered as external driver in models of land-use - conflict dynamics when seasonal or mean values are used as external driver.

  17. Grassland Carbon Change in Northern China due to Contemporary and Future Land Use and Land Cover Change

    NASA Astrophysics Data System (ADS)

    Xin, Xiaoping; Li, Zhenwang; Sleeter, Benjamin; Wilson, Tamara; Sherba, Jason; Liu, Jinxun; Chen, Baorui; Tang, Huan; Gong, Peng; Zhu, Zhiliang

    2016-04-01

    In the past 20 years, more than 7 million hectares of natural grassland in north China were tilled and utilized. The increasing land use and land cover (LULC) change has resulted in the loss of ecosystem carbon storage and had an enormous impact on terrestrial carbon cycling. However, there are large uncertainties in quantifying the effect of LULC change on the historical and future carbon stock of these grasslands. This study used the integrated state-and-transition simulation model (ST-Sim) and the CENTURY model to track the effects of LULC change on ecosystem carbon storage from 1991 to 2030 in northern China. Four remote sensing based land cover maps of China (1-km spatial resolution for 1990, 2000, 2005, and 2010) were used to generate recent historical land cover transition rates and annual land cover maps. In addition, four LULC projections were downscaled from the Intergovernmental Panel on Climate Change (IPCC) representative concentration pathway (RCP) data and were used to derive future land cover changes of China. The CENTURY model was used to derive input parameters for the carbon stock and flow module in ST-Sim to track changes in carbon stocks and fluxes over the model period. The MODIS net primary productivity (NPP) product and regional living biomass and soil organic carbon maps were used to initialize the model. Five simulations were conducted including one with no historical and future land cover change (ST-Sim_NLULC) and four historical LULC change plus future RCP projection scenarios (ST-Sim_LULC). Simulation outputs included annual historical and future LULC maps, regional total NPP and net biome productivity (NBP) for the 1991-2030 period. Results showed that during the 40 years, the study area experienced drastic LULC change especially during the period 1991-2000. Compared to the ST-Sim_NLULC (i.e. no land use change) results, the ST-Sim LULC scenarios each show an increased NPP, a lower NBP before 2000, and a slighter higher NBP post-2000

  18. Impacts of conflict on land use and land cover in the Imatong Mountain region of South Sudan and northern Uganda

    NASA Astrophysics Data System (ADS)

    Gorsevski, Virginia B.

    The Imatong Mountain region of South Sudan makes up the northern most part of the Afromontane conservation 'biodiversity hotspot' due to the numerous species of plants and animals found here, some of which are endemic. At the same time, this area (including the nearby Dongotana Hills and the Agoro-Agu region of northern Uganda) has witnessed decades of armed conflict resulting from the Sudan Civil War and the presence of the Ugandan Lord's Resistance Army (LRA). The objective of my research was to investigate the impact of war on land use and land cover using a combination of satellite remote sensing data and semi-structured interviews with local informants. Specifically, I sought to (1) assess and compare changes in forest cover and location during both war and peace; (2) compare trends in fire activity with human population patterns; and (3) investigate the underlying causes influencing land use patterns related to war. I did this by using a Disturbance Index (DI), which isolates un-vegetated spectral signatures associated with deforestation, on Landsat TM and ETM+ data in order to compare changes in forest cover during conflict and post-conflict years, mapping the location and frequency of fires in subsets of the greater study area using MODIS active fire data, and by analyzing and summarizing information derived from interviews with key informants. I found that the rate of forest recovery was significantly higher than the rate of disturbance both during and after wartime in and around the Imatong Central Forest Reserve (ICFR) and that change in net forest cover remained largely unchanged for the two time periods. In contrast, the nearby Dongotana Hills experienced relatively high rates of disturbance during both periods; however, post war period losses were largely offset by gains in forest cover, potentially indicating opposing patterns in human population movements and land use activities within these two areas. For the Agoro-Agu Forest Reserve (AFR) region

  19. Land cover changes associated with recent energy development in the Williston Basin; Northern Great Plains, USA.

    PubMed

    Preston, Todd M; Kim, Kevin

    2016-10-01

    The Williston Basin in the Northern Great Plains has experienced rapid energy development since 2000. To evaluate the land cover changes resulting from recent (2000-2015) development, the area and previous land cover of all well pads (pads) constructed during this time were determined, the amount of disturbed and reclaimed land adjacent to pads was estimated, land cover changes were analyzed over time for three different well types, and the effects from future development were predicted. The previous land cover of the 12,990ha converted to pads was predominately agricultural (49.5%) or prairie (47.4%) with lesser amounts of developed (2.3%), aquatic (0.5%), and forest (0.4%). Additionally, 12,121ha has likely been disturbed and reclaimed. The area required per gas well remained constant through time while the land required per oil well increased initially and then decreased as development first shifted from conventional to unconventional drilling and then to multi-bore pads. For non-oil-and-gas wells (i.e. stratigraphic test wells, water wells, and injection wells), the area per well increased through time likely due to increased produced water disposal requirements. Future land cover change is expected to be 2.7 times greater than recent development with much of the development occurring in five counties in the core Bakken development area. Direct land cover change and disturbance from recent and expected development are predicted to affect 0.4% of the landscape across the basin; however, in the core Bakken development area, 2.3% of the landscape will be affected including 2.1% of the remaining grassland. Although future development will result in significant land cover change, evolving industry practices and proactive siting decisions, such as development along energy corridors and placing pads in areas previously altered by human activity, have the potential to reduce the ecological effects of future energy development in the Williston Basin. PMID:27318516

  20. Land cover changes associated with recent energy development in the Williston Basin; Northern Great Plains, USA

    USGS Publications Warehouse

    Preston, Todd M.; Kim, Kevin

    2016-01-01

    The Williston Basin in the Northern Great Plains has experienced rapid energy development since 2000. To evaluate the land cover changes resulting from recent (2000 – 2015) development, the area and previous land cover of all well pads (pads) constructed during this time was determined, the amount of disturbed and reclaimed land adjacent to pads was estimated, land cover changes were analyzed over time for three different well types, and the effects from future development were predicted. The previous land cover of the 12,990 ha converted to pads was predominately agricultural (49.5%) or prairie (47.4%) with lesser amounts of developed (2.3%), aquatic (0.5%), and forest (0.4%). Additionally, 12,121 ha have likely been disturbed and reclaimed. The area required per gas well remained constant through time while the land required per oil well increased initially and then decreased as development first shifted from conventional to unconventional drilling and then to multi-bore pads. For non-oil-and- gas wells (i.e. stratigraphic test wells, water wells, injection wells, etc.), the area per well increased through time likely due to increased produced water disposal requirements. Future land cover change is expected to be 2.7 times greater than recent development with much of the development occurring in five counties in the core Bakken development area. Direct land cover change and disturbance from recent and expected development are predicted to affect 0.4% of the landscape across the basin; however, in the core Bakken development area, 2.3% of the landscape will be affected including 2.1% of the remaining grassland. Although future development will result in significant land cover change, evolving industry practices and proactive siting decisions, such as development along energy corridors and placing pads in areas previously altered by human activity, have the potential to reduce the ecological effects of future energy development in the Williston Basin.

  1. 21st century projections of terrestrial carbon fluxes over Northern Eurasia: the role of land legacy, future land use change and future climate change

    NASA Astrophysics Data System (ADS)

    Monier, Erwan; Kicklighter, David; Sokolov, Andrei

    2015-04-01

    Northern Eurasia is a major player in the global carbon budget because of boreal forests and peatlands. Circumpolar boreal forests alone contain more than five times the amount of carbon of temperate forests and almost double the amount of carbon of the world's tropical forests. In this study, we investigate possible changes in terrestrial fluxes of carbon dioxide over Northern Eurasia over the 21st century. We estimate the contributions of land legacy, future land use change and future climate change. We present three sets of simulations of terrestrial fluxes of carbon dioxide over Northern Eurasia from 1500 to 2100 using the MBL Terrestrial Ecosystem Model (TEM), a process-based ecosystem/biogeochemistry model: (1) fixed land cover corresponding to year 2005; (2) historical land use land cover change from 1500 to 2005 and fixed land cover corresponding to year 2005 until 2100; (3) historical land use land cover change from 1500 to 2005 and RCP land use land cover change scenarios until 2100. Each set of simulations is forced by a large ensemble of climate simulations using the MIT IGSM-CAM model, which accounts for the uncertainty in projections of future climate change in order to obtain robust estimates of the contribution of land legacy, land use change and climate change. The climate ensemble consists of: two emissions scenarios, a "business as usual" unconstrained emissions scenario and a stabilization scenario, similar to, respectively, the RCP8.5 and RCP4.5 scenarios; three values of climate sensitivity (2.0°C, 2.5°C and 4.5°C corresponding to the 5th percentile, median, and 95th percentile of the marginal posterior probability density function with uniform prior) and associated net aerosol forcing chosen to best reproduce observed climate change; and five different representations of natural variability. The results of this study provide new insight on projections of future terrestrial carbon fluxes over Northern Eurasia.

  2. Implications of land use change in tropical northern Africa under global warming

    NASA Astrophysics Data System (ADS)

    Brücher, T.; Claussen, M.; Raddatz, T.

    2015-12-01

    A major link between climate and humans in tropical northern Africa, and the Sahel in particular, is land use and associated land cover change, mainly where subsistence farming prevails. Here we assess possible feedbacks between the type of land use and harvest intensity and climate by analysing a series of idealized GCM experiments using the Max Planck Institute Earth System Model (MPI-ESM). The baseline for these experiments is a simulation forced by the RCP8.5 (radiation concentration pathway) scenario, which includes strong greenhouse gas emissions and anthropogenic land cover changes. The anthropogenic land cover changes in the RCP8.5 scenario include a mixture of pasture and agriculture. In subsequent simulations, we replace the entire area affected by anthropogenic land cover change in the region between the Sahara in the north and the Guinean Coast in the south (4 to 20° N) with either pasture or agriculture. In a second set-up we vary the amount of harvest in the case of agriculture. The RCP8.5 baseline simulation reveals strong changes in the area mean agriculture and monsoon rainfall. In comparison with these changes, any variation of the type of land use in the study area leads to very small, mostly insignificantly small, additional differences in mean temperature and annual precipitation change in this region. These findings are only based on the specific set-up of our experiments, which only focuses on variations in the kind of land use, and not the increase in land use, over the 21st century, nor whether land use is considered at all. Within the uncertainty of the representation of land use in current ESMs, our study suggests marginal feedback between land use changes and climate changes triggered by strong greenhouse gas emissions. Hence as a good approximation, climate can be considered as an external forcing: models investigating land-use-conflict dynamics can run offline by prescribing seasonal or mean values of climate as a boundary condition

  3. Soil respiration patterns for four major land-use types of the agro-pastoral region of northern China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land-use types and management practices are critical factors that affect soil CO2 efflux (Rs). In the agro-pastoral area of northern China, land-use types have changed considerably during the last 60 years due to changes in the social-economic status of the human population and associated changes i...

  4. Non-growing season soil CO2 efflux patterns in five land-use types in northern China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Overgrazing and unsuitable farming practices have led to grassland degradation in northern China. This studhy examined soil CO2 efflux (Fc) from five land-use types during the non-growing season on the southeastern edge of the Mongolian Plateau in China. The land-use types included three native v...

  5. Estimating potential wind erosion of agricultural lands in northern China using the Revised Wind Erosion Equation (RWEQ) and GIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fine materials emissions from severe wind-induced soil erosion have multiple impacts on land degradation and environmental pollution in the agro-pastoral ecotone in northern China (APEC). Assessment of wind erosion for the agricultural land management systems in APEC are needed to determine which sy...

  6. Groundwater sapping as the cause of irreversible desertification of Hunshandake Sandy Lands, Inner Mongolia, northern China.

    PubMed

    Yang, Xiaoping; Scuderi, Louis A; Wang, Xulong; Scuderi, Louis J; Zhang, Deguo; Li, Hongwei; Forman, Steven; Xu, Qinghai; Wang, Ruichang; Huang, Weiwen; Yang, Shixia

    2015-01-20

    In the middle-to-late Holocene, Earth's monsoonal regions experienced catastrophic precipitation decreases that produced green to desert state shifts. Resulting hydrologic regime change negatively impacted water availability and Neolithic cultures. Whereas mid-Holocene drying is commonly attributed to slow insolation reduction and subsequent nonlinear vegetation-atmosphere feedbacks that produce threshold conditions, evidence of trigger events initiating state switching has remained elusive. Here we document a threshold event ca. 4,200 years ago in the Hunshandake Sandy Lands of Inner Mongolia, northern China, associated with groundwater capture by the Xilamulun River. This process initiated a sudden and irreversible region-wide hydrologic event that exacerbated the desertification of the Hunshandake, resulting in post-Humid Period mass migration of northern China's Neolithic cultures. The Hunshandake remains arid and is unlikely, even with massive rehabilitation efforts, to revert back to green conditions. PMID:25561539

  7. Groundwater sapping as the cause of irreversible desertification of Hunshandake Sandy Lands, Inner Mongolia, northern China

    PubMed Central

    Yang, Xiaoping; Scuderi, Louis A.; Wang, Xulong; Scuderi, Louis J.; Zhang, Deguo; Li, Hongwei; Forman, Steven; Xu, Qinghai; Wang, Ruichang; Huang, Weiwen; Yang, Shixia

    2015-01-01

    In the middle-to-late Holocene, Earth’s monsoonal regions experienced catastrophic precipitation decreases that produced green to desert state shifts. Resulting hydrologic regime change negatively impacted water availability and Neolithic cultures. Whereas mid-Holocene drying is commonly attributed to slow insolation reduction and subsequent nonlinear vegetation–atmosphere feedbacks that produce threshold conditions, evidence of trigger events initiating state switching has remained elusive. Here we document a threshold event ca. 4,200 years ago in the Hunshandake Sandy Lands of Inner Mongolia, northern China, associated with groundwater capture by the Xilamulun River. This process initiated a sudden and irreversible region-wide hydrologic event that exacerbated the desertification of the Hunshandake, resulting in post-Humid Period mass migration of northern China’s Neolithic cultures. The Hunshandake remains arid and is unlikely, even with massive rehabilitation efforts, to revert back to green conditions. PMID:25561539

  8. Mapping of land cover in Northern California with simulated HyspIRI images

    NASA Astrophysics Data System (ADS)

    Clark, M. L.; Kilham, N. E.

    2014-12-01

    Land-cover maps are important science products needed for natural resource and ecosystem service management, biodiversity conservation planning, and assessing human-induced and natural drivers of land change. Most land-cover maps at regional to global scales are produced with remote sensing techniques applied to multispectral satellite imagery with 30-500 m pixel sizes (e.g., Landsat, MODIS). Hyperspectral, or imaging spectrometer, imagery measuring the visible to shortwave infrared regions (i.e., full range) of the spectrum have shown improved capacity to map plant species and coarser land-cover associations, yet techniques have not been widely tested at regional and greater spatial scales. The Hyperspectral Infrared Imager (HyspIRI) mission is a full-range hyperspectral and thermal satellite being considered for development by NASA (hyspiri.jpl.nasa.gov). A hyperspectral satellite, such as HyspIRI, will provide detailed spectral and temporal information at global scales that could greatly improve our ability to map land cover with greater class detail and spatial and temporal accuracy than possible with conventional multispectral satellites. The broad goal of our research is to assess multi-temporal, HyspIRI-like satellite imagery for improved land cover mapping across a range of environmental and anthropogenic gradients in California. In this study, we mapped FAO Land Cover Classification System (LCCS) classes over 30,000 km2 in Northern California using multi-temporal HyspIRI imagery simulated from the AVIRIS airborne sensor. The Random Forests classification was applied to predictor variables derived from the multi-temporal hyperspectral data and accuracies were compared to that from Landsat 8 OLI. Results indicate increased mapping accuracy using HyspIRI multi-temporal imagery, particularly in discriminating different forest life-form types, such as mixed conifer and broadleaf forests and open- and closed-canopy forests.

  9. Northern Eurasia Earth Science Partnership Initiative (NEESPI): Focus on Dry Lands

    NASA Astrophysics Data System (ADS)

    Groisman, P. Y.; Ivanov, S.; Mátyás, S.; Meshcherskaya, A.; Razuvaev, V.

    2010-12-01

    NEESPI is an interdisciplinary program of internationally-supported Earth systems and science research that addresses large-scale and long-term manifestations of climate and environmental change over Northern Eurasia (http://neespi.org). The NEESPI Study Area includes: Former Soviet Union, Northern China, Mongolia, Fennoscandia, and Eastern Europe. Presentation will focus on the rationale of the initiative, its major steps, and plans for the future within the expansive dry land areas of Northern Eurasia in the southern boundary of the forest zone, forest-steppe, steppe, semi-desert, and desert climatic zones. The drought (xeric) limit of closed forests, an ecologically very sensitive zone, is present in nearly all of the countries within the latitudinal belt from 40° to 55°N in Eurasia - or if not, its appearance is predicted. According to predictions, increasing frequency of droughts and sinking groundwater levels may threaten the stability of forest ecosystems of this zone. These changes forecast specific problems not only for forestry itself, but also regarding the multitude of ecological services provided by forests for the society. In addition, we present our latest results on the changes in the warm season characteristics over the dry land zone within the former USSR during the period of instrumental observations (50 to 100 years). These include: changes in the precipitation distribution (an increase of the frequency of heavy and extreme precipitation with a simultaneous increase of the duration of the no-rain periods); earlier onset of the vegetation period; earlier spring snow cover retreat; and changes in indices that characterize "fire weather" and agricultural droughts (more humid weather conditions west of the Ural Mountains and drier weather conditions over most of northern Asia).

  10. Mapping of the Land Cover Spatiotemporal Characteristics in Northern Russia Caused by Climate Change

    NASA Astrophysics Data System (ADS)

    Panidi, E.; Tsepelev, V.; Torlopova, N.; Bobkov, A.

    2016-06-01

    The study is devoted to the investigation of regional climate change in Northern Russia. Due to sparseness of the meteorological observation network in northern regions, we investigate the application capabilities of remotely sensed vegetation cover as indicator of climate change at the regional scale. In previous studies, we identified statistically significant relationship between the increase of surface air temperature and increase of the shrub vegetation productivity. We verified this relationship using ground observation data collected at the meteorological stations and Normalised Difference Vegetation Index (NDVI) data produced from Terra/MODIS satellite imagery. Additionally, we designed the technique of growing seasons separation for detailed investigation of the land cover (shrub cover) dynamics. Growing seasons are the periods when the temperature exceeds +5°C and +10°C. These periods determine the vegetation productivity conditions (i.e., conditions that allow growth of the phytomass). We have discovered that the trend signs for the surface air temperature and NDVI coincide on planes and river floodplains. On the current stage of the study, we are working on the automated mapping technique, which allows to estimate the direction and magnitude of the climate change in Northern Russia. This technique will make it possible to extrapolate identified relationship between land cover and climate onto territories with sparse network of meteorological stations. We have produced the gridded maps of NDVI and NDWI for the test area in European part of Northern Russia covered with the shrub vegetation. Basing on these maps, we may determine the frames of growing seasons for each grid cell. It will help us to obtain gridded maps of the NDVI linear trend for growing seasons on cell-by-cell basis. The trend maps can be used as indicative maps for estimation of the climate change on the studied areas.

  11. A regional climate simulation study with land cover dynamics in Northern China

    NASA Astrophysics Data System (ADS)

    Wang, Hanjie; Ju, Yongmao; Li, Jianyun; Qiu, Guoyu

    2007-09-01

    A social-economic database based on the Governmental Statistical Annals, county-to-county investigation, literature verification, as well as the satellite identification was completed recently by the Remote Sensing and GIS Research Center, Beijing Normal University of China. The GIS Operational System handing this database not only provides details of the social, ecological, and economic information of the Northern China's 13 provinces since earlier 1950s, but also gives out predictions of these information by 2050 with different sceneries concerning the population increase, land use variation, governmental policy adjusting, administrating capability, science and technology development, National GDP increment, as well as world climate change. Aims at further regional climate simulation study, there is a special module nested in the GIS Operational System that interprets the county-level administrative data-units to a 60 × 60 km numerical mesh-grid suitable for climate model. By incorporating the land use dynamics provided by the above database, the new generation of the Regional Integrate Environment Modeling System (RIEMS2.0) was used for climate simulation study. The preliminary simulation studies show that: (1) the regional climate will be affected by the LULC variation because the equilibrium of water and heat transfer in the air-vegetation interface is changed; (2) the integrate impact of the LULC variation on climate (such as temperature, humidity and net long-wave radiation, precipitation) is not only limited to the Northern China where LULC varies, but also to the whole numerical domain where the LULC does not vary at all; (3) the ecological construction engineering implemented in Northern China including the Green-Great Wall construction engineering, the replace farming with forestry and grass movement, and the natural forest conservation etc has shown and will work positively on the eco-environment improvement, particularly shown as the increased

  12. Periglacial landforms at the Phoenix landing site and the northern plains of Mars

    NASA Astrophysics Data System (ADS)

    Mellon, Michael T.; Arvidson, Raymond E.; Marlow, Jeffrey J.; Phillips, Roger J.; Asphaug, Erik

    2008-11-01

    We examine potentially periglacial landforms in Mars Orbiter Camera (MOC) and High Resolution Imaging Science Experiment (HiRISE) images at the Phoenix landing site and compare them with numerical models of permafrost processes to better understand the origin, nature, and history of the permafrost and the surface of the northern plains of Mars. Small-scale (3-6 m) polygonal-patterned ground is ubiquitous throughout the Phoenix landing site and northern plains. Larger-scale (20-25 m) polygonal patterns and regularly spaced (20-35 m) rubble piles (localized collections of rocks and boulders) are also common. Rubble piles were previously identified as ``basketball terrain'' in MOC images. The small polygon networks exhibit well-developed and relatively undegraded morphology, and they overlay all other landforms. Comparison of the small polygons with a numerical model shows that their size is consistent with a thermal contraction origin on current-day Mars and are likely active. In addition, the observed polygon size is consistent with a subsurface rheology of ice-cemented soil on depth scales of about 10 m. The size and morphology of the larger polygonal patterns and rubble piles indicate a past episode of polygon formation and rock sorting in thermal contraction polygons, while the ice table was about twice as deep as it is presently. The pervasive nature of small and large polygons, and the extensive sorting of surface rocks, indicates that widespread overturning of the surface layer to depths of many meters has occurred in the recent geologic past. This periglacial reworking has had a significant influence on the landscape at the Phoenix landing site and over the Martian northern plains.

  13. Land Use Change and Hydrologic Processes in High-Elevation Tropical Watersheds of the Northern Andes

    NASA Astrophysics Data System (ADS)

    Avery, W. A.; Riveros-Iregui, D. A.; Covino, T. P.; Peña, C.

    2013-12-01

    The humid tropics cover one-fifth of the Earth's land surface and generate the greatest amount of runoff of any biome globally, but remain poorly understood and understudied. Humid tropical regions of the northern and central Andes have experienced greater anthropogenic land-use/land-cover (LULC) change than nearly any other high mountain system in the world. Vast expanses of this region are currently undergoing rapid transformation to farmland for production of potatoes and pasture for cattle grazing. Although the humid tropics have some of the highest runoff ratios, precipitation, and largest river flows in the world, there is a lack of scientific literature that addresses hydrologic processes in these regions and very few field observations are available to inform management strategies to ensure the sustainability of water resources of present and future generations. We seek to improve understanding of hydrologic processes and feedbacks in the humid tropics using existing and new information from two high-elevation watersheds that span a LULC gradient in the Andes Mountains of Colombia. One site is located in the preserved Chingaza Natural National Park in Central Colombia (undisturbed). The second site is located ~60 km to the northwest and has experienced considerable LULC change over the last 40 years. Combined, these watersheds deliver over 80% of the water resources to Bogotá and neighboring communities. These watersheds have similar climatological characteristics (including annual precipitation), but have strong differences in LULC which result in substantial differences in hydrologic response and streamflow dynamics. We present an overview of many of the pressing issues and effects that land degradation and climate change are posing to the long-term sustainability of water resources in the northern Andes. Our overarching goal is to provide process-based knowledge that will be useful to prevent, mitigate, or respond to future water crises along the Andean

  14. Representing Northern Peatland Hydrology and Biogeochemistry within the Community Land Model

    NASA Astrophysics Data System (ADS)

    Shi, X.; Ricciuto, D. M.; Xu, X.; Thornton, P. E.; Hanson, P. J.; Mao, J.; Sebestyen, S.; Griffiths, N.

    2015-12-01

    Northern peatlands are projected to become very important in future carbon-climate feedback due to their large carbon storage and vulnerability to changes in hydrology and climate impacts. Understanding the hydrology and biogeochemistry is a fundamental task for projecting the fate of massive carbon stores in these systems under future climate change. Models have started to address microtopographic controls on peatland hydrology, but none have considered a prognostic calculation of water table dynamics in vegetated peatlands rather than prescribed regional water tables. We introduced here a new configuration of the Community Land Model (CLM), which includes a fully prognostic water table calculation between hummock and hollow microtopography in a vegetated peatland. We further integrated the hydrology treatment with vertically structured soil organic matter pools, and a newly developed microbial functional group-based methane module. The model was further used to test against observational data obtained within Spruce and Peatland Responses Under Climatic and Environmental Change (SPRUCE) project. Results for water table dynamic, carbon profile, and land surface fluxes of carbon dioxide and methane were reasonable. Model simulations showed that warming and elevated CO2 had significant impacts on land surface fluxes of methane and carbon dioxide. The warming-induced hydrological changes are another factors influencing biogeochemistry along soil profiles and land surface gas fluxes. These preliminary results provide some insights for field experiments as well as data-model comparison in next phase of the SPRUCE project.

  15. Monitoring Contrasting Land Management in the Savanna Landscapes of Northern Australia

    NASA Astrophysics Data System (ADS)

    Franklin, Donald C.; Petty, Aaron M.; Williamson, Grant J.; Brook, Barry W.; Bowman, David M. J. S.

    2008-04-01

    We compared measures of ecosystem state across six adjacent land-tenure groups in the intact tropical savanna landscapes of northern Australia. Tenure groups include two managed by Aboriginal owners, two national parks, a cluster of pastoral leases, and a military training area. This information is of relevance to the debate about the role of indigenous lands in the Australian conservation estate. The timing and frequency of fire was determined by satellite imagery; the biomass and composition of the herb-layer and the abundance of large feral herbivores by field surveys; and weediness by analysis of a Herbarium database. European tenures varied greatly in fire frequencies but were consistently burnt earlier in the dry season than the two Aboriginal tenures, the latter having intermediate fire frequencies. Weeds were more frequent in the European tenures, whilst feral animals were most abundant in the Aboriginal tenures. This variation strongly implies a signature of current management and/or recent environmental history. We identify indices suitable for monitoring of management outcomes in an extensive and sparsely populated landscape. Aboriginal land offers a unique opportunity for the conservation of biodiversity through the maintenance of traditional fire regimes. However, without financial support, traditional practices may prove unsustainable both economically and because exotic weeds and feral animals will alter fire regimes. An additional return on investment in Aboriginal land management is likely to be improved livelihoods and health outcomes for these disadvantaged communities.

  16. Development of Ecological Land Classification and mapping in support of forest management in northern Newfoundland, Canada.

    PubMed

    Bajzak, D; Roberts, B A

    1996-01-01

    For the sustainable development of forest land, as recently prescribed by the Canadian Forest Strategy, a land classification project in northern Newfoundland was initiated to support the local forest management activities. The method adopted here is a modification of the Canadian Committee for Ecological Land Classification's (CCELC) system, and it applies various levels of mapping to uniform areas based on geomorphology, soils, vegetation, climate, water, and fauna.In this study, all CCELC levels were mapped; resulting maps were digitized and imported into a Geographic Informations System (GIS). The GIS data base contained the following maps: 1) digital terrain model, 2) bedrock geology, 3) surficial geology, 4) forest inventory, and 5) various levels of the ecological land classification, including Vegetation Types at the lowest level. In addition to the mapping, mensurational data were analyzed to provide stand and stock tables for each of the forest types, including growth curves that could be entered into specific forest growth modelling systems to predict wood supply scenarios based upon different management interventions. PMID:24198006

  17. Land-Water-Atmosphere Linkages in the Landscape of Northern Alaska

    NASA Astrophysics Data System (ADS)

    Shaver, G. R.

    2014-12-01

    The landscape of northern Alaska holds very large stores of organic matter, carbon, and nitrogen, most of it in the soils of terrestrial tundra ecosystems including the upper 1-2 meters of underlying permafrost. Although much of this organic matter and its element content accumulates and cycles relatively slowly, understanding the dynamics of these stores at a landscape scale requires a perspective that includes not only the vertical exchanges with the atmosphere but also the lateral movement and processing of carbon and nitrogen as they as they are transported down hillslopes and into and through lakes and streams. The pool sizes and residence times of C and N differ greatly among lakes, streams, and the terrestrial ecosystems at different locations along hillslopes and in catchments, yet they are all linked through this lateral transport and through the stoichiometry of organic matter cycling. Landscape-scale C and N budgets for the northern foothills of the Brooks Range, Alaska, indicate that significant amounts of C removed from the atmosphere by photosynthesis on land are later returned to the atmosphere from lakes and streams. Nitrogen, on the other hand, is much more strongly retained by terrestrial ecosystems and moves much more slowly across the land surface; this N retention and recycling is an important regulator of terrestrial productivity and C accumulation. These relationships are likely to change with climate and especially with climate-related disturbances including wildfire and thermal erosion of permafrost.

  18. Land surface phenology, hydrology and CO2 fluxes of forests and grasslands in Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Xiao, X.; Li, C.; Kurbatova, J.; Varlagin, A.; Zhang, J.; Wu, J.; Wu, W.; Biradar, C.; Chen, J.

    2008-12-01

    Land surface phenology (LSP) is a key indicator of ecosystem dynamics under a changing environment. Changes in phenology of plants affect the carbon cycle, water cycle, climate through photosynthesis and evapotranspiration. We have combined satellite observations, CO2 eddy flux tower sites and process-based biogeochemical model to improve our understanding of the effect of land surface phenology and hydrology on gross primary production (GPP), ecosystem respiration and net ecosystem exchange of CO2 (NEE) from a variety of ecosystem types. In this paper, we will present case studies from two spruce forest sites (wet spruce forest and dry spruce forest) in Russia, a deciduous broadleaf forest site and a grassland site in Northern China. Among the three vegetation indices (Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and Land Surface Water Index (LSWI), both LSWI and EVI agreed well with the photosynthetically active period (as defined by estimated GPP data from CO2 eddy flux tower sites) than NDVI does. The Vegetation Photosynthesis Model (VPM), which uses EVI and LSWI data as input, provides improved prediction of GPP for various types of terrestrial ecosystems. NEE is the difference between GPP and ecosystem respiration. Simulations of processed-based DNDC model for two spruce forests (wet and dry spruce forests) suggested that ecosystem respiration (and consequently NEE) fluxes are highly sensitive to water table depth at the sites. Because Northern Eurasia has a large area of wetlands and underwent significant climate change, potential change in water table due to hydrological processes could have significant implication to the carbon fluxes and carbon balance (carbon sink or source) in the region.

  19. Sea/land breeze climatological characteristics along the northern Croatian Adriatic coast

    NASA Astrophysics Data System (ADS)

    Prtenjak, M. Telišman; Grisogono, B.

    2007-11-01

    Climatological characteristics along the northern Croatian Adriatic coast have been examined for nine meteorological stations for the summertime sea/land breeze circulation. The stations considered are Pula-airport, Opatija, Rijeka, Senj, Malinska, Rijeka-airport, Mali Lošinj, Rab and Zadar. The hourly surface measurements at each station from June to September for the period 1991 2004 as well as the radiosoundings in Zadar (from 2002 to 2004) were used for the analysis. A dataset with the sea/land breeze days was formed according to the several criteria. The mean daily maxima of both air and sea surface temperatures were more influenced by the large scale disturbances toward north (e.g. in Rijeka or Opatija) compared to the values for e.g. Zadar. Furthermore, the influence of the large scale disturbances diminished toward the south concerning the sea land temperature difference only at the stations placed at Rijeka Bay and Velebit channel. The strongest sea breeze was found at Pula-airport and the most frequent ones at Opatija and Zadar. At Senj the rarest, the weakest and the shortest sea breeze was observed. The climatological records of wind speed and air-sea temperature difference (Δ T) showed for Opatija, Malinska and Zadar that the maximum measured wind speed is around 4.5 °C confirming the nonlinear relationship between the sea breeze speeds and the Δ T during the day. At most stations, the clockwise rotation of the hodographs prevails which is typical for the Northern hemisphere due to Coriolis force, with the exception at Senj and Malinska. While the hodographs for Pula, Rijeka-airport and Mali Lošinj display a later onset of the prevailing sea breeze because of the interaction among several sea breeze circulations, the results for Opatija, Zadar and Senj show considerably distorted hodographs because of the nearby channeling of the air flow.

  20. Geology and petrogenesis of the Kirkpatrick Basalt, Pain Mesa and Solo Nunatak, northern Victoria Land, Antarctica

    SciTech Connect

    Mensing, T.M.

    1987-01-01

    The flows on Pain Mesa were divided into a Lower Suite and an Upper Suite based on differences in their chemical compositions. The Upper Suite has higher concentrations of SiO/sub 2/, alkalies, total Fe, MnO, TiO/sub 2/, and P/sub 2/O/sub 5/ than the Lower Suite. In addition, the flows of the Upper Suite are homogeneous in chemical composition compared to the Lower Suite which is differentiated. The isotope compositions of Sr and O of the Lower Suite are positively correlated which indicates that the magma was contaminated by crustal material. The isotopic and chemical compositions of the flows of the Lower Suite were explained by fractional crystallization and simultaneous assimilation of a crustal contaminant. The initial Sr isotope ratios of the Upper Suite, calculated for an assumed age of 175 Ma, were lower than those of the Lower Suite, and are not constant. However, by lowering the assumed age of the Upper Suite to 92 Ma the range of the initial Sr-isotope ratios was greatly reduced. Paleomagnetic results and K-Ar dating of Ferrar rocks at the Litell Rocks Nunatak in northern Victoria Land also support the hypothesis that the Upper Suite is Cretaceous in age. The magma source of both suites has elevated /sup 87/Sr//sup 86/Sr ratios compared to normal mantle values because of prior enrichment in Rb. The magma source was enriched in Rb about 475 Ma years ago. This data coincides with the Ross Orogeny which may reflect a causal relationship between these events. The occurrence of igneous activity in northern Victoria Land and Marie Byrd Land were juxtaposed during the Mesozoic Era but were later separated as a result of major right lateral displacement along the Transantarctic rift system.

  1. Representing northern peatland microtopography and hydrology within the Community Land Model

    NASA Astrophysics Data System (ADS)

    Shi, X.; Thornton, P. E.; Ricciuto, D. M.; Hanson, P. J.; Mao, J.; Sebestyen, S. D.; Griffiths, N. A.; Bisht, G.

    2015-11-01

    Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological dynamics in northern

  2. Representing northern peatland microtopography and hydrology within the Community Land Model

    DOE PAGESBeta

    Shi, Xiaoying; Thornton, Peter E.; Ricciuto, Daniel M.; Hanson, Paul J.; Mao, Jiafu; Sebestyen, Stephen D.; Griffiths, Natalie A.; Bisht, Gautam

    2015-11-12

    Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to representmore » the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. Furthermore, the new model provides improved predictive capacity for seasonal hydrological

  3. Representing northern peatland microtopography and hydrology within the Community Land Model

    DOE PAGESBeta

    Shi, X.; Thornton, P. E.; Ricciuto, D. M.; Hanson, P. J.; Mao, J.; Sebestyen, S. D.; Griffiths, N. A.; Bisht, G.

    2015-02-20

    Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to representmore » the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts significant hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological

  4. Representing northern peatland microtopography and hydrology within the Community Land Model

    SciTech Connect

    Shi, Xiaoying; Thornton, Peter E.; Ricciuto, Daniel M.; Hanson, Paul J.; Mao, Jiafu; Sebestyen, Stephen D.; Griffiths, Natalie A.; Bisht, Gautam

    2015-11-12

    Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. Furthermore, the new model provides improved predictive capacity for seasonal hydrological dynamics

  5. Representing northern peatland microtopography and hydrology within the Community Land Model

    SciTech Connect

    Shi, X.; Thornton, P. E.; Ricciuto, D. M.; Hanson, P. J.; Mao, J.; Sebestyen, S. D.; Griffiths, N. A.; Bisht, G.

    2015-02-20

    Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts significant hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological dynamics

  6. Representing northern peatland microtopography and hydrology within the Community Land Model

    NASA Astrophysics Data System (ADS)

    Shi, X.; Thornton, P. E.; Ricciuto, D. M.; Hanson, P. J.; Mao, J.; Sebestyen, S. D.; Griffiths, N. A.; Bisht, G.

    2015-02-01

    Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts significant hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological dynamics

  7. Classification of satellite time series-derived land surface phenology focused on the northern Fertile Crescent

    NASA Astrophysics Data System (ADS)

    Bunker, Brian

    Land surface phenology describes events in a seasonal vegetation cycle and can be used in a variety of applications from predicting onset of future drought conditions, to revealing potential limits of historical dry farming, to guiding more accurate dating of archeological sites. Traditional methods of monitoring vegetation phenology use data collected in situ. However, vegetation health indices derived from satellite remote sensor data, such as the normalized difference vegetation index (NDVI), have been used as proxy for vegetation phenology due to their repeated acquisition and broad area coverage. Land surface phenology is accessible in the NDVI satellite record when images are processed to be intercomparable over time and temporally ordered to create a time series. This study utilized NDVI time series to classify areas of similar vegetation phenology in the northern Fertile Crescent, an area from the middle Mediterranean coast to southern/south-eastern Turkey to western Iran and northern Iraq. Phenological monitoring of the northern Fertile Crescent is critical due to the area's minimal water resources, susceptibility to drought, and understanding ancient historical reliance on precipitation for subsistence dry farming. Delineation of phenological classes provides areal and temporal synopsis of vegetation productivity time series. Phenological classes were developed from NDVI time series calculated from NOAA's Advanced Very High Resolution Radiometer (AVHRR) imagery with 8 × 8 km spatial resolution over twenty-five years, and by NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) with 250 × 250 m spatial resolution over twelve years. Both AVHRR and MODIS time series were subjected to data reduction techniques in spatial and temporal dimensions. Optimized ISODATA clusters were developed for both of these data reduction techniques in order to compare the effects of spatial versus temporal aggregation. Within the northern Fertile Crescent study area

  8. Ecoregional differences in late-20th-century land-use and land-cover change in the U.S. northern great plains

    USGS Publications Warehouse

    Auch, R.F.; Sayler, K.L.; Napton, D.E.; Taylor, J.L.; Brooks, M.S.

    2011-01-01

    Land-cover and land-use change usually results from a combination of anthropogenic drivers and biophysical conditions found across multiple scales, ranging from parcel to regional levels. A group of four Level 111 ecoregions located in the U.S. northern Great Plains is used to demonstrate the similarities and differences in land change during nearly a 30-year period (1973-2000) using results from the U.S. Geological Survey's Land Cover Trends project. There were changes to major suites of land-cover; the transitions between agriculture and grassland/shrubland and the transitions among wetland, water, agriculture, and grassland/ shrubland were affected by different factors. Anthropogenic drivers affected the land-use tension (or land-use competition) between agriculture and grassland/shrubland land-covers, whereas changes between wetland and water land-covers, and their relationship to agriculture and grassland/shrubland land-covers, were mostly affected by regional weather cycles. More land-use tension between agriculture and grassland/shrubland landcovers occurred in ecoregions with greater amounts of economically marginal cropland. Land-cover change associated with weather variability occurred in ecoregions that had large concentrations of wetlands and water impoundments, such as the Missouri River reservoirs. The Northwestern Glaciated Plains ecoregion had the highest overall estimated percentage of change because it had both land-use tension between agriculture and grassland/shrubland land-covers and wetland-water changes. ?? 2011 Copyright by the Center for Great Plains Studies, University of Nebraska-Lincoln.

  9. Observation on internal waves propagation during Land breeze event in Northern Tyrrhenian coast

    NASA Astrophysics Data System (ADS)

    Martellucci, Riccardo; Pierattini, Alberto; Paladini de Mendoza, Francesco; Melchiorri, Cristiano; Piermattei, Viviana; Ciampa, Francesco; Marcelli, Marco

    2015-04-01

    Internal wave propagation and water column mixing phenomena play an important role in many marine ecosystem coastal process. In Northern Tyrrhenian coast the experimental proposed approach is aimed to identify these type of oscillation in presence of breeze circulation. Along the Tyrrhenian coast summer period climate conditions allow the generations of high frequency land-sea breeze events. This local circulation, land-sea breeze indeed, may generate significant modifications of the sea waters physical parameters. Thay often appear as internal gravity waves especially in presence of stratified water and stable thermocline. Since the whole investigated process evolves on diurnal scale and in the space of a few miles the sampling plan was operated with a series of oceanographic surveys at 40 meters depth with 20 minutes interval one from another between 5 a.m. and 11 a.m. and they were repeted during each summers between 2012 - 2014. Coupled with the acquisition of physical parameters current data were collected with 500 kHz ADCP every 20s, the resolution of vertical profiles of CTD matches the ADCP 1 meter magnitude vertical resolution. in order to investigate the water column layers dynamics behavior, Brunt-Vaisala and Richardson number were computed using the sampled physical parameters. Coastal surveys analysis highlights the presence of temperature oscillation in proximity of the thermocline and bottom layers; these oscillations have been observed during all measure surveys, when the land breeze was over. Indeed the land breeze tends to generate an offshore transport causing bottom layers to lift. At the same time solar radiation heating causes a sink of the surface layers which flatten the layers in proximity of the thermocline. Therefore the oscillations of temperature observed during the oceanographic surveys have to considered as internal waves, as during earlier studies conducted in the Tyrrhenian Sea has been observed.

  10. Reactivated tectonic boundaries and implications for the reconstruction of southeastern Australia and northern Victoria Land, Antarctica

    SciTech Connect

    Foster, D.A.; Gleadow, A.J.W. )

    1992-03-01

    Rifted continental margins are strongly influenced by the location of zones of preexisting crustal weakness. Apatite fission track thermochronological data indicate that the Paleozoic lithospheric boundary between the Kanmantoo and Lachlan fold belts in western Victoria, Australia, was reactivated during Mesozoic rifting as a transfer fault. To the east of this boundary, 1-2 km of material was denuded during extension, while essentially no denudation took place during rifting to the west. The correlated tectonic boundary within the Bowers terrane of northern Victoria Land, Antarctica, was also reactivated upon rifting. During fragmentation of Gondwana, movement on this zone perpendicular to the direction of rifting probably determined the location of the Tasman Fracture Zone. When Australia and Antarctica are reconstructed along the trace of the Tasman Fracture Zone, the tectonic boundary in Victoria falls into precise alignment with the Bowers terrane.

  11. Assessment of the Nature, Distribution and Causes of Land Subsidence in Central and Northern Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Othman, A.; Sultan, M.; Al Harbi, H.; Youssef, A.; Ahmed, M.; Emil, M.; Zabramwi, Y.; Alzahrani, S.; Bahamil, A.; Chouinard, K.

    2014-12-01

    Numerous land subsidence events have been recently reported from central and northern parts of the Kingdom of Saudi Arabia in Hail, Al Qassim, Al Jowf, and Buraydah Provinces. In some cases, these incidences resulted in losses in life and property. In this study, an integrated (field, geologic, remote sensing) approach is applied to accomplish the following: (1) identify the spatial distribution and extent of areas affected by subsidence (TASK I), (2) identify the factor(s) causing such subsidence (TASK II), and (3) identify areas threatened by such phenomena across northern and central parts of the Kingdom using criteria extracted from TASK II (TASK III). A three-fold approach was applied: (1) visits were conducted to collect field observations from reported subsidence locations, (2) spatial correlations were implemented in a web-based GIS environment for the reported subsidence locations in relation to relevant co-registered static datasets (e.g., rock and soil types, geologic structures) and temporal datasets (e.g., groundwater extraction, landuse/landcover, distribution and magnitude of earthquakes), (3) subsidence rates were extracted applying the Small BAseline Subset (SBAS) radar interferometric technique and using European Remote Sensing satellite-1 (ERS-1), ERS-2, and the Environmental Satellite (Envisat) data sets. Our findings (from radar interferometric studies) indicate that the distribution of areas undergoing subsidence are consistent/correlate with: (1) reported subsidence locations, but reveal many additional unreported subsidence locations, (2) irrigated lands, especially those witnessing a progressive increase in agricultural activities with time; (3) outcrops of the Saq sandstone aquifer system, the main source for fresh groundwater in the Kingdom, (4) outcrops the Minjur limestone formation that are subject to karstification; and (5) urban centers lacking appropriate sewage and drainage systems.

  12. Complete Genome Sequence of Cryobacterium arcticum Strain PAMC 27867, Isolated from a Sedimentary Rock Sample in Northern Victoria Land, Antarctica.

    PubMed

    Lee, Jaejin; Cho, Ahnna; Yang, Jae Young; Woo, Jusun; Lee, Hong Kum; Hong, Soon Gyu; Kim, Ok-Sun

    2016-01-01

    Cryobacterium arcticum PAMC 27867, a psychrotolerant, Gram-positive bacterium, was isolated from a sedimentary rock sample collected at Eureka Spurs in northern Victoria Land, Antarctica. Here, we report the genome sequence of C. arcticum PAMC 27867. PMID:27587812

  13. Complete Genome Sequence of Cryobacterium arcticum Strain PAMC 27867, Isolated from a Sedimentary Rock Sample in Northern Victoria Land, Antarctica

    PubMed Central

    Lee, Jaejin; Cho, Ahnna; Yang, Jae Young; Woo, Jusun; Lee, Hong Kum; Hong, Soon Gyu

    2016-01-01

    Cryobacterium arcticum PAMC 27867, a psychrotolerant, Gram-positive bacterium, was isolated from a sedimentary rock sample collected at Eureka Spurs in northern Victoria Land, Antarctica. Here, we report the genome sequence of C. arcticum PAMC 27867. PMID:27587812

  14. Is the northern high latitude land-based CO2 sink weakening?

    SciTech Connect

    Mcguire, David; Kicklighter, David W.; Gurney, Kevin R; Burnside, Todd; Melillo, Jerry

    2011-01-01

    Studies indicate that, historically, terrestrial ecosystems of the northern high latitude region may have been responsible for up to 60% of the global net land-based sink for atmospheric CO2. However, these regions have recently experienced remarkable modification of the major driving forces of the carbon cycle, including surface air temperature warming that is significantly greater than the global average and associated increases in the frequency and severity of disturbances. Whether arctic tundra and boreal forest ecosystems will continue to sequester atmospheric CO2 in the face of these dramatic changes is unknown. Here we show the results of model simulations that estimate a 41 Tg C yr-1 sink in the boreal land regions from 1997 to 2006, which represents a 73% reduction in the strength of the sink estimated for previous decades in the late 20th Century. Our results suggest that CO2 uptake by the region in previous decades may not be as strong as previously estimated. The recent decline in sink strength is the combined result of 1) weakening sinks due to warming-induced increases in soil organic matter decomposition and 2) strengthening sources from pyrogenic CO2 emissions as a result of the substantial area of boreal forest burned in wildfires across the region in recent years. Such changes create positive feedbacks to the climate system that accelerate global warming, putting further pressure on emission reductions to achieve atmospheric stabilization targets.

  15. Is the northern high-latitude land-based CO2 sink weakening?

    USGS Publications Warehouse

    Hayes, D.J.; McGuire, A.D.; Kicklighter, D.W.; Gurney, K.R.; Burnside, T.J.; Melillo, J.M.

    2011-01-01

    Studies indicate that, historically, terrestrial ecosystems of the northern high-latitude region may have been responsible for up to 60% of the global net land-based sink for atmospheric CO2. However, these regions have recently experienced remarkable modification of the major driving forces of the carbon cycle, including surface air temperature warming that is significantly greater than the global average and associated increases in the frequency and severity of disturbances. Whether Arctic tundra and boreal forest ecosystems will continue to sequester atmospheric CO2 in the face of these dramatic changes is unknown. Here we show the results of model simulations that estimate a 41 Tg C yr-1 sink in the boreal land regions from 1997 to 2006, which represents a 73% reduction in the strength of the sink estimated for previous decades in the late 20th century. Our results suggest that CO 2 uptake by the region in previous decades may not be as strong as previously estimated. The recent decline in sink strength is the combined result of (1) weakening sinks due to warming-induced increases in soil organic matter decomposition and (2) strengthening sources from pyrogenic CO2 emissions as a result of the substantial area of boreal forest burned in wildfires across the region in recent years. Such changes create positive feedbacks to the climate system that accelerate global warming, putting further pressure on emission reductions to achieve atmospheric stabilization targets. Copyright 2011 by the American Geophysical Union.

  16. Assessing naturalness in northern great lakes forests based on historical land-cover and vegetation changes.

    PubMed

    Gimmi, Urs; Radeloff, Volker C

    2013-08-01

    The concept of naturalness was developed to assess to what degree landscapes represent a natural state. Protected areas are often regarded as the remnants of untouched landscapes although many landscapes commonly perceived as pristine have a long history of human impact. Here, we introduced a historical perspective into the concept of naturalness and the analysis of the effectiveness of protected areas by analyzing historical trajectories in land-cover and forest communities for the Pictured Rocks National Lakeshore on Michigan's Upper Peninsula (USA). Distribution of land-cover and forest community types was reconstructed for pre-settlement time (around 1850), the height of agricultural expansion (1928), and modern conditions (2000). Naturalness of the landscape was assessed by analyzing similarity between pre-settlement and current conditions and by assessing landscape continuity (1850-1928-2000). We compared changes in the strictly protected park core zone with those in the inland buffer zone with ongoing sustainable logging, and a not protected area adjacent to the park. Forest was the dominant land-cover type over the entire study period. We detected a gradient in land-cover continuity from the core zone (81 % continuity) to the inland buffer zone (74 %) and the area outside the park (66 %). Northern hardwood was the dominating forest type in all time points with high continuity (76 %). In contrast, pine forests show a more dynamic pattern with more than 50 % of the initial forests switching to non-forest or early succession forest types by 1928. More than half of the study area was considered as "natural virgin" (no changes in land-cover and forest community type) with a higher portion within the park than in the adjacent area. In contrast, areas with low naturalness are more abundant outside the park. Our study demonstrates the value of integrating historical information into naturalness assessments and the results provide useful information for future

  17. Assessment of Model Estimates of Land-Atmosphere CO2 Exchange Across Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Rawlins, M. A.; McGuire, A. D.; Kimball, J. S.; Dass, P.

    2014-12-01

    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity and mobilization of soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) dynamics through analysis of net ecosystem productivity (NEP) and the component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time as simulated by a set of process models over a region spanning the drainage basin of northern Eurasia. The retrospective simulations were conducted over the period 1960-2009 at 0.5 degree resolution. Performance benchmarks are made through comparisons of model estimates and CO2 fluxes derived from tower eddy covariance measurements and satellite data driven GPP estimates. The site comparisons show the timing of peak summer productivity to be well simulated. Modest overestimates in model GPP and ER are also found, which are relatively higher for two boreal forest validation sites. Averaged across the models, NEP increases by 135% of the mean (10% to 400% among the models) from the first to last ten years of record (1960-1969 vs 2000-2009), with a weakening terrestrial carbon sink indicated over recent decades. Vegetation net primary productivity (NPP) increased by 8 to 30%, contributing to soil carbon storage gains, while model mean residence time for soil organic carbon decreased by -10% (-5% to -16% among the models) due to enhanced litter decomposition and heterotrophic respiration (Rh) losses offsetting soil carbon inputs. Our analysis points to improvements in model elements controlling vegetation productivity and soil respiration as being most beneficial for reducing uncertainty in land-atmosphere CO2 exchange. These advances require collection of new field data in key areas and the incorporation of spatial information on vegetation characteristics into models.

  18. Evaporation and land surface energy budget at the Salar de Atacama, Northern Chile

    NASA Astrophysics Data System (ADS)

    Kampf, Stephanie K.; Tyler, Scott W.; Ortiz, Cristián A.; Muñoz, José F.; Adkins, Paula L.

    2005-08-01

    Playa systems are driven by evaporation processes, yet the mechanisms by which evaporation occurs through playa salt crusts are still poorly understood. In this study we examine playa evaporation as it relates to land surface energy fluxes, salt crust characteristics, groundwater and climate at the Salar de Atacama, a 3000 km 2 playa in northern Chile containing a uniquely broad range of salt crust types. Land surface energy budget measurements were taken at eight representative sites on this playa during winter (August 2001) and summer (January 2002) seasons. Measured values of net all-wave radiation were highest at vegetated and rough halite crust sites and lowest over smooth, highly reflective salt crusts. Over most of the Salar de Atacama, net radiation was dissipated by means of soil and sensible heat fluxes. Dry salt crusts tended to heat and cool very quickly, whereas soil heating and cooling occurred more gradually at wetter vegetated sites. Sensible heating was strongly linked to wind patterns, with highest sensible heat fluxes occurring on summer days with strong afternoon winds. Very little energy available at the land surface was used to evaporate water. Eddy covariance measurements could only constrain evaporation rates to within 0.1 mm d -1, and some measured evaporation rates were less than this margin of uncertainty. Evaporation rates ranged from 0.1 to 1.1 mm d -1 in smooth salt crusts around the margin of the salar and from 0.4 to 2.8 mm d -1 in vegetated areas. No evaporation was detected from the rugged halite salt crust that covers the interior of the salar, though the depth to groundwater is less than 1 m in this area. These crusts therefore represent a previously unrecorded end member condition in which the salt crusts form a practically impermeable barrier to evaporation.

  19. Carbon dynamics of Oregon and Northern California forests and potential land-based carbon storage.

    PubMed

    Hudiburg, Tara; Law, Beverly; Turner, David P; Campbell, John; Donato, Dan; Duane, Maureen

    2009-01-01

    Net uptake of carbon from the atmosphere (net ecosystem production, NEP) is dependent on climate, disturbance history, management practices, forest age, and forest type. To improve understanding of the influence of these factors on forest carbon stocks and flux in the western United States, federal inventory data and supplemental field measurements at additional plots were used to estimate several important components of the carbon balance in forests in Oregon and Northern California during the 1990s. Species- and ecoregion-specific allometric equations were used to estimate live and dead biomass stores, net primary productivity (NPP), and mortality. In the semiarid East Cascades and mesic Coast Range, mean total biomass was 8 and 24 kg C/m2, and mean NPP was 0.30 and 0.78 kg C.m(-2).yr(-1), respectively. Maximum NPP and dead biomass stores were most influenced by climate, whereas maximum live biomass stores and mortality were most influenced by forest type. Within ecoregions, mean live and dead biomass were usually higher on public lands, primarily because of the younger age class distribution on private lands. Decrease in NPP with age was not general across ecoregions, with no marked decline in old stands (>200 years old) in some ecoregions. In the absence of stand-replacing disturbance, total landscape carbon stocks could theoretically increase from 3.2 +/- 0.34 Pg C to 5.9 +/- 1.34 Pg C (a 46% increase) if forests were managed for maximum carbon storage. Although the theoretical limit is probably unattainable, given the timber-based economy and fire regimes in some ecoregions, there is still potential to significantly increase the land-based carbon storage by increasing rotation age and reducing harvest rates. PMID:19323181

  20. Assessment of model estimates of land-atmosphere CO2 exchange across Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Rawlins, M. A.; McGuire, A. D.; Kimball, J. S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; Peng, S.; Rinke, A.; Saito, K.; Zhang, W.; Alkama, R.; Bohn, T. J.; Ciais, P.; Decharme, B.; Gouttevin, I.; Hajima, T.; Ji, D.; Krinner, G.; Lettenmaier, D. P.; Miller, P.; Moore, J. C.; Smith, B.; Sueyoshi, T.

    2015-07-01

    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960-2009 at 0.5° resolution, which is a scale common among many global carbon and climate model simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m-2 yr-2, equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960-1969 vs. 2000-2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our analysis points to improvements in model elements

  1. Assessment of model estimates of land-atmosphere CO2 exchange across Northern Eurasia

    DOE PAGESBeta

    Rawlins, M. A.; McGuire, A. D.; Kimball, J. S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; et al

    2015-07-28

    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960–2009 at 0.5° resolution, which is a scale common among many global carbon and climate modelmore » simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m⁻² yr⁻², equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960–1969 vs. 2000–2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our analysis points to improvements in

  2. Effects of land-use and climate on Holocene vegetation composition in northern Europe

    NASA Astrophysics Data System (ADS)

    Marquer, Laurent; Gaillard, Marie-José; Sugita, Shinya; Poska, Anneli; Trondman, Anna-Kari; Mazier, Florence; Nielsen, Anne Birgitte; Fyfe, Ralph; Jönsson, Anna Maria

    2016-04-01

    Prior to the advent of agriculture, broad-scale vegetation patterns in Europe were controlled primarily by climate. Early agriculture can be detected in palaeovegetation records, but the relative extent to which past regional vegetation was climatically or anthropogenically-forced is of current scientific interest. Using comparisons of transformed pollen data, climate-model data, dynamic vegetation model simulations and anthropogenic land-cover change data, this study aims to estimate the relative impacts of human activities and climate on the Holocene vegetation composition of northern Europe at a subcontinental scale. The REVEALS model was used for pollen-based quantitative reconstruction of vegetation (RV). Climate variables from ECHAM and the extent of human deforestation from KK10 were used as explanatory variables to evaluate their respective impacts on RV. Indices of vegetation-composition changes based on RV and climate-induced vegetation simulated by the LPJ-GUESS model (LPJG) were used to assess the relative importance of climate and anthropogenic impacts. The results show that climate is the major predictor of Holocene vegetation changes until 5000 years ago. The similarity in rate of change and turnover between RV and LPJG decreases after this time. Changes in RV explained by climate and KK10 vary for the last 2000 years; the similarity in rate of change, turnover, and evenness between RV and LPJG decreases to the present. The main conclusions provide important insights on Neolithic forest clearances that affected regional vegetation from 6700 years ago, although climate (temperature and precipitation) still was a major driver of vegetation change (explains 37% of the variation) at the subcontinental scale. Land use became more important around 5000-4000 years ago, while the influence of climate decreased (explains 28% of the variation). Land-use affects all indices of vegetation compositional change during the last 2000 years; the influence of climate

  3. Assessment of model estimates of land-atmosphere CO2 exchange across northern Eurasia

    USGS Publications Warehouse

    Rawlins, M.A.; McGuire, A.D.; Kimball, J.S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; Peng, S.; Rinke, A.; Saito, K.; Zhang, W.; Alkama, R.; Bohn, T. J.; Ciais, P.; Decharme, B.; Gouttevin, I.; Hajima, T.; Ji, D.; Krinner, G.; Lettenmaier, D.P.; Miller, P.; Moore, J.C.; Smith, B.; Sueyoshi, T.

    2015-01-01

    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960–2009 at 0.5° resolution, which is a scale common among many global carbon and climate model simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m−2 yr−2, equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960–1969 vs. 2000–2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our analysis points to improvements in model

  4. Quantifying Biogeochemical Cycles of CO2 and CH4 over the Land and Aquatic Ecosystems in Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Zhuang, Q.

    2015-12-01

    Under the auspices of the NASA Land-Use and Land-Cover Change Program, we have made a significant progress on quantifying both CO2 and CH4 biogeochemical cycles of the land and aquatic systems in Northern Eurasia over the last several decades. Our quantification is based on in situ and satellite data of ecosystem distribution, land cover distribution, carbon, water and energy fluxes, fire disturbances, plant biomass inventory, atmospheric CO2 and CH4, and meteorology. The evaluated process-based modeling systems for both land and aquatic ecosystems for the historical period have been used to project carbon fluxes during the 21st century over this region. The uncertainty associated with these carbon-based gases is also quantified. This presentation will update these quantifications by examining: 1) the impacts of fire disturbances on land ecosystem CO2 budget in the last few decades; 2) net CO2 and CH4 exchanges of the land and aquatic ecosystems in both historical and future periods. Our study has also assessed the role of permafrost dynamics in both land and aquatic ecosystem carbon and water dynamics in this region. Our research provides an integrated land and aquatic ecosystem model that can be used to address biogeochemical cycles of carbon and water in this climate-sensitive region.

  5. Proposed Mars Surveyor Landing Sites in Northern Meridiani Sinus, Southern Elysium Planitia, and Argyre Planitia

    NASA Technical Reports Server (NTRS)

    Parker, T. J.; Edgett, K. S.

    1998-01-01

    from the present study images from current and future orbiter spacecraft, until such data does become readily available. Within each proposed region, it may be possible to identify additional sites once these data become available. Second, the fine-component thermal inertia data, should be greater than about 5 or 6 cgs Units (10(exp -3) cal/sq cm s(exp -0.5)/K). Low thermal inertias imply dusty environments, which could pose a mobility hazard. Similarly, the albedo of the site should not be particularly high, which would also suggest dusty surfaces. Low albedos are preferred, as they often coincide with low Viking red:violet ratios and indicate less dusty surfaces. Next, the Modeled Block Abundance should also not be too high or too low. Based on the Viking Lander and Mars Pathfinder experiences, percentages of blocks should be on the order of 5-25%. Too many blocks could pose a hazard to the landing and mobility. Too few blocks could also indicate a dusty surface. Primary Landing Site: Northern Meridiani Sinus (Proposed by T. J. Parker and K., S. Edgett) Vital Statistics: (1) Latitude, Longitude: 0-3 N, 350-2 W. *Elevation (Viking): about0.5-1.5 Ian. (2) Viking Orbiter Image coverage: Excellent coverage by 15 - 25 m/pixel images (orbits 709A and 410B). Possible stereo coverage in region where two orbits overlap (probably small parallax angle, as these orbits are not listed in NASA Contractor Report 3501) (3) Albedo: about .18 -.26 (4) Block Abundance: 5-26% (5)Fine-Component Thermal Inertia: 5-9 cgs units This region consists of bright deposits similar to those described by Edgett et al, that also lie within a prominent dark albedo region. These deposits are flat-lying, to such a degree that they ramp against topography rather than draping over it. This led Edgett and Parker to suggest that they may be subaqueous sediments, possibly lacustrine or marine evaporites, laid down sometime from the late Noachian to middle Hesperian (age determination pending crater counts

  6. Land Use and Water Quality Along a Mekong Tributary in Northern Lao P.D.R.

    NASA Astrophysics Data System (ADS)

    Ribolzi, Olivier; Cuny, Juliette; Sengsoulichanh, Phonexay; Mousquès, Claire; Soulileuth, Bounsamai; Pierret, Alain; Huon, Sylvain; Sengtaheuanghoung, Oloth

    2011-02-01

    Improving access to clean water has the potential to make a major contribution toward poverty reduction in rural communities of Lao P.D.R. This study focuses on stream water quality along a Mekong basin tributary, the Houay Xon that flows within a mountainous, mosaic land-use catchment of northern Lao P.D.R. To compare direct water quality measurements to the perception of water quality within the riparian population, our survey included interviews of villagers. Water quality was found to vary greatly depending on the location along the stream. Overall, it reflected the balance between the stream self-cleaning potential and human pressure on the riparian zone: (i) high bacteria and suspended load levels occurred where livestock are left to free-range within the riparian zone; (ii) very low oxygen content and high bacteriological contamination prevailed downstream from villages; (iii) high concentrations of bacteria were consistently observed along urbanized banks; (iv) low oxygen content were associated with the discharge of organic-rich wastewater from a small industrial plant; (v) very high suspended load and bacteria levels occurred during flood events due to soil erosion from steep cultivated hill slopes. Besides these human induced pollutions we also noted spontaneous enrichments in metals in wetland areas fed by dysoxic groundwater. These biophysical measurements were in agreement with the opinions expressed by the majority of the interviewees who reported poor and decreasing water quality in the Houay Xon catchment. Based on our survey, we propose recommendations to improve or maintain stream water quality in the uplands of northern Lao P.D.R.

  7. Take-off and landing forces and the evolution of controlled gliding in northern flying squirrels Glaucomys sabrinus.

    PubMed

    Paskins, Keith E; Bowyer, Adrian; Megill, William M; Scheibe, John S

    2007-04-01

    Flying squirrels are well known for their ability to glide between trees at the top of a forest canopy. We present experimental performance and behavioural evidence that flight in flying squirrels may have evolved out of a need to control landing forces. Northern flying squirrels were filmed jumping from a horizontal branch to a much larger vertical pole. These were both slightly compliant (less than 1.9 mm N(-1)), and instrumented using strain gauges so that forces could be measured. Take-off and landing forces were both positively correlated with horizontal range between 0.5 and 2.5 m (r=0.355 and r=0.811, respectively, P<0.05), but not significantly different to each other at each range tested. Take-off forces ranged from 1 to 10 bodyweights, and landing forces were between 3 and 10 bodyweights. Glide angles increased rapidly with horizontal range, approaching 45 degrees at 3 m, above which they gradually decreased, suggesting that northern flying squirrels are optimised for long distance travel. We show that northern flying squirrels initiate full gliding posture at ranges of less than 1 m, without landing any higher than an equivalent ballistic projectile. However, this gliding posture enables them to pitch upwards, potentially stalling the wing, and spreads the landing reaction force over all four extended limbs. At steeper approach angles of close to 45 degrees , flying squirrels were unable to pitch up sufficiently and landed forelimbs first, consequently sustaining higher impact forces. We investigate four hypotheses to explain the origin of flight in these animals and conclude that the need to reduce landing impact forces was most likely to have stimulated the development of aerial control in flying squirrels. PMID:17401124

  8. A global climate model based, Bayesian climate projection for northern extra-tropical land areas

    NASA Astrophysics Data System (ADS)

    Arzhanov, Maxim M.; Eliseev, Alexey V.; Mokhov, Igor I.

    2012-04-01

    Projections with contemporary global climate models (GCMs) still markedly deviate from each other on magnitude of climate changes, in particular, in middle to subpolar latitudes. In this work, a climate projection based on the ensemble of 18 CMIP3 GCM models forced by SRES A1B scenario is performed for the northern extra-tropical land. To assess the change of soil state, off-line simulations are performed with the Deep Soil Simulator (DSS) developed at the A.M.Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS). This model is forced by output of the above-mentioned GCM simulations. Ensemble mean and ensemble standard deviation for any variable are calculated by using Bayesian averaging which allows to enhance a contribution from more realistic models and diminish that from less realistic models. As a result, uncertainty for soil and permafrost variables become substantially narrower. The Bayesian weights for each model are calculated based on their performance for the present-day surface air temperature (SAT) and permafrost distributions, and for SAT trend during the 20th century. The results, except for intra-ensemble standard deviations, are not very sensitive to particular choice of Bayesian traits. Averaged over the northern extra-tropical land, annual mean surface air temperature in the ensemble increases by 3.1 ± 1.4 K (ensemble mean±intra-ensemble standard deviation) during the 21st century. Precipitation robustly increases in the pan-Arctic and decreases in the Mediterranean/Black Sea region. The models agree on near-surface permafrost degradation during the 21st century. The area underlain by near-surface permafrost decreases from the contemporary value 20 ± 3 mln sq. km to 14 ± 3 mln sq. km in the late 21st century. This leads to risk for geocryological hazard due to soil subsidence. This risk is classified as moderate to high in the southern and western parts of Siberia and Tibet in Eurasia, and in the region from Alaska

  9. Unimodal Latitudinal Pattern of Land-Snail Species Richness across Northern Eurasian Lowlands

    PubMed Central

    Horsák, Michal; Chytrý, Milan

    2014-01-01

    Large-scale patterns of species richness and their causes are still poorly understood for most terrestrial invertebrates, although invertebrates can add important insights into the mechanisms that generate regional and global biodiversity patterns. Here we explore the general plausibility of the climate-based “water-energy dynamics” hypothesis using the latitudinal pattern of land-snail species richness across extensive topographically homogeneous lowlands of northern Eurasia. We established a 1480-km long latitudinal transect across the Western Siberian Plain (Russia) from the Russia-Kazakhstan border (54.5°N) to the Arctic Ocean (67.5°N), crossing eight latitudinal vegetation zones: steppe, forest-steppe, subtaiga, southern, middle and northern taiga, forest-tundra, and tundra. We sampled snails in forests and open habitats each half-degree of latitude and used generalized linear models to relate snail species richness to climatic variables and soil calcium content measured in situ. Contrary to the classical prediction of latitudinal biodiversity decrease, we found a striking unimodal pattern of snail species richness peaking in the subtaiga and southern-taiga zones between 57 and 59°N. The main south-to-north interchange of the two principal diversity constraints, i.e. drought stress vs. cold stress, explained most of the variance in the latitudinal diversity pattern. Water balance, calculated as annual precipitation minus potential evapotranspiration, was a single variable that could explain 81.7% of the variance in species richness. Our data suggest that the “water-energy dynamics” hypothesis can apply not only at the global scale but also at subcontinental scales of higher latitudes, as water availability was found to be the primary limiting factor also in this extratropical region with summer-warm and dry climate. A narrow zone with a sharp south-to-north switch in the two main diversity constraints seems to constitute the dominant and general

  10. Unimodal latitudinal pattern of land-snail species richness across northern Eurasian lowlands.

    PubMed

    Horsák, Michal; Chytrý, Milan

    2014-01-01

    Large-scale patterns of species richness and their causes are still poorly understood for most terrestrial invertebrates, although invertebrates can add important insights into the mechanisms that generate regional and global biodiversity patterns. Here we explore the general plausibility of the climate-based "water-energy dynamics" hypothesis using the latitudinal pattern of land-snail species richness across extensive topographically homogeneous lowlands of northern Eurasia. We established a 1480-km long latitudinal transect across the Western Siberian Plain (Russia) from the Russia-Kazakhstan border (54.5°N) to the Arctic Ocean (67.5°N), crossing eight latitudinal vegetation zones: steppe, forest-steppe, subtaiga, southern, middle and northern taiga, forest-tundra, and tundra. We sampled snails in forests and open habitats each half-degree of latitude and used generalized linear models to relate snail species richness to climatic variables and soil calcium content measured in situ. Contrary to the classical prediction of latitudinal biodiversity decrease, we found a striking unimodal pattern of snail species richness peaking in the subtaiga and southern-taiga zones between 57 and 59°N. The main south-to-north interchange of the two principal diversity constraints, i.e. drought stress vs. cold stress, explained most of the variance in the latitudinal diversity pattern. Water balance, calculated as annual precipitation minus potential evapotranspiration, was a single variable that could explain 81.7% of the variance in species richness. Our data suggest that the "water-energy dynamics" hypothesis can apply not only at the global scale but also at subcontinental scales of higher latitudes, as water availability was found to be the primary limiting factor also in this extratropical region with summer-warm and dry climate. A narrow zone with a sharp south-to-north switch in the two main diversity constraints seems to constitute the dominant and general pattern of

  11. Impacts of Changing Climate and Land Cover on Water and Carbon Dynamics in Northern Eurasia

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Zhuang, Q.; Kicklighter, D. W.; Tchebakova, N.; Chen, J.; Melillo, J. M.

    2014-12-01

    The ecosystems in Northern Eurasia (NE) play an important role in the global climate system due to their vast land coverage, higher-than-global average rate of warming, and the potential feedbacks to the global climate. Water and carbon fluxes interact with each other and vary with climate change and land cover change (LUC). To understand the coupled effects of climate change and LUC on water and carbon dynamics in NE, we modified the algorithms for evapotranspiration (ET), incorporated the effects of forest stand age and fires on these dynamics, and assimilated forest inventory data and eddy covariance observations into the Terrestrial Ecosystem Model (TEM) to better estimate water and carbon fluxes. With consideration of ET from uplands and wetlands, evaporation from water bodies, and snow sublimation, TEM substantially improves its estimation of ET and runoff. Estimated regional ET varies between 263.5-369.3 mm yr-1 during 1979-2008 depending on the choice of forcing data. With the most accurate available forcing data, modification to TEM results in a decrease of root mean square error from 527.74 km3 yr-1 to 126.23 km3 yr-1 for the total discharge estimates of the six largest watersheds in NE. Site-level experiments show that with/without consideration of forest stand age and fires leads to 12.8-53.5% differences in ET estimates, and shifts NE ecosystems between carbon sink and source activities depending on fire severities. Consequently, consideration of these impacts at regional scales may result in large differences in estimates of water and carbon fluxes across NE. Our study highlights the role of snow in the hydrometeorology of NE, and suggests that the quality of forcing data remains a major challenge for accurate quantification of regional water balance, and urges consideration of forest stand age and fires in estimation of water and carbon fluxes in NE.

  12. Mineralogy and Geochemistry of Granitic rocks within Lichen Hills, Outback Nunatak, Northern Victoria Land, Antarctica

    NASA Astrophysics Data System (ADS)

    KIM, T.; KIM, Y.; Lee, I.; Lee, J.; Woo, J.

    2015-12-01

    The study areas, Lichen Hills and Outback Nunatak are located in the Northern Victoria Land which is close to Pacific Ocean side of Transantarctic Mountain (TAM), Antarctica. According to the study of Zeller and Dreschoff (1990), the radioactivity values of Lichen hills and Frontier Mt. area in the Victoria Land were very high. To identify the geochemical characteristics of granitic rocks in these areas, 13 samples of Lichen Hills rocks and 4 samples of Outback Nunatak rocks are analyzed. For mineralogical study, samples were observed in macroscale as well as microscale including microscope electron probe analysis. Rock samples of Lichen Hills, Outback Nunatak are mainly leucogranite and granitic pegmatite. These rock samples are composed of quartz, k-feldspar, plagioclase, muscovite, garnet, tourmaline like granite. In SEM-EDS analysis, the observed light colored minerals show relatively high Th, U, Dy, Ce, Nb concentration. This suggests that rock samples may contain minerals such as fergusonite, monazite, thorite, allanite, karnasurtite which are considered to be REE-bearing minerals. Samples of related rocks have been analyzed in terms of major, trace and rare earth element (REE) concentrations using X-ray fluorescence (XRF) spectrometer and Inductively Coupled Plasma Mass Spectrometer (ICP-MS). As concentration of SiO2 increase, Al2O3, TiO2, Fe2O3, MgO, P2O5 concentration decrease and Na2O, K2O, MnO concentration increase. Analyzed trace elements and REE are normalized using CI Chondrite, Primitive mantle. The normalized data show that LREE are enriched compared to HREE. The distinct negative anomalies of Eu, Sr are observed, indicating that rock-forming melts are fairly processed state of fractional crystallization. It means that Th, U, Nb, Ta are much enriched in the melts.

  13. Land use changes and its climatic implications in Northern Italy during the Dark Ages

    NASA Astrophysics Data System (ADS)

    Oeggl, Klaus; Oeggl-Wahlmüller, Notburga; Festi, Daniela; Zagermann, Marcus

    2016-04-01

    Here we present an interdisciplinary study on land use changes in Northern Italy at the transition from the Roman Empire to the Early Middle Ages. The combination of archaeological data and high-resolution pollen analyses carried out in the Fiavè basin (Trentino) provide a detailed insight in socio-economic changes and its implications with climate in the Dark Ages. The vegetation in this area is dominated up to 1000 m by submediterranian trees like Fraxinus ornus and Ostrya carpinifolia, superseded by a mixed Fagus and Abies forest with variable amounts of Picea abies. Since 2008 archaeological surveys in the Fiavè basin as well as excavations conducted on a fortified hill-top settlement (castrum) in 985m register the settlement development of this settlement cluster and reveal an almost continuous occupation from Roman to Early Medieval Times. In addition a high-resolution pollen record from a 1.30 m thick peat sequence of the bog "Palude di Fiave" discloses four main phases: (1) in the Late Iron Age high amounts of arboreal pollen and the spread of Abies demonstrate a decrease in settlement activity suggested by wetter climate conditions. (2) During the Roman Empire a phase with arable farming in the basin starts. Olea, Juglans and Castanea sativa are introduced and document the onset of horticulture in this region. (3) After 300 AD - during the Migration Period - the wet and cool conditions have had poor impact on settlement activity. Agricultural (Cerealia) and nitrophilous indicators (Plantago, Chenopodiaceae, Urticaceae) are continuously proved. However a change within the cultivated crops in relation to the climate conditions is observed. Subsequently a progressive recovery of Pinus followed by Abies and Fagus marks the climatic improvement at the beginning of the Early Medieval Times. (4) The time from 600 to 800 AD is characterized by increasing frequency and diversity of anthropogenic-related indicators. The implications of these land use changes with

  14. Scenarios of Future Climate and Land-Management Effects on Carbon Stocks in Northern Patagonian Shrublands

    NASA Astrophysics Data System (ADS)

    Carrera, Analia; Ares, Jorge; Labraga, Juan; Thurner, Stephanie; Bertiller, Mónica

    2007-12-01

    We analyzed the possible effects of grazing management and future climate change on carbon (C) stocks in soils of northern Patagonian shrublands. To this aim, we coupled the outputs of three (HadCM3, CSIRO Mk2, and CCSR/NIES) global climate models to the CENTURY (v5.3) model of terrestrial C balance. The CENTURY model was initialized with long-term field data on local biome physiognomy, seasonal phenologic trends, and prevailing land-management systems and was validated with recent sequences of 1-km Normalized Difference Vegetation Index (MODIS-Terra) images and soil C data. In the tested scenarios, the predicted climate changes would result in increased total C in soil organic matter (SOMTC). Maximum SOMTC under changed climate forcing would not differ significantly from that expected under baseline conditions (8 kg m-2). A decrease in grazing intensity would result in SOMTC increases of 11% to 12% even if climate changes did not occur. Climate change would account for SOMTC increases of 5% to 6%.

  15. Scenarios of future climate and land-management effects on carbon stocks in northern Patagonian shrublands.

    PubMed

    Carrera, Analia; Ares, Jorge; Labraga, Juan; Thurner, Stephanie; Bertiller, Mónica

    2007-12-01

    We analyzed the possible effects of grazing management and future climate change on carbon (C) stocks in soils of northern Patagonian shrublands. To this aim, we coupled the outputs of three (HadCM3, CSIRO Mk2, and CCSR/NIES) global climate models to the CENTURY (v5.3) model of terrestrial C balance. The CENTURY model was initialized with long-term field data on local biome physiognomy, seasonal phenologic trends, and prevailing land-management systems and was validated with recent sequences of 1-km Normalized Difference Vegetation Index (MODIS-Terra) images and soil C data. In the tested scenarios, the predicted climate changes would result in increased total C in soil organic matter (SOMTC). Maximum SOMTC under changed climate forcing would not differ significantly from that expected under baseline conditions (8 kg m(-2)). A decrease in grazing intensity would result in SOMTC increases of 11% to 12% even if climate changes did not occur. Climate change would account for SOMTC increases of 5% to 6%. PMID:17786512

  16. Paddy rice productivity under climate and land-use change in northern Japan

    NASA Astrophysics Data System (ADS)

    Yoshida, R.; Fukui, S.; Shimada, T.; Hasegawa, T.; Iwasaki, T.

    2013-12-01

    An evaluation of the best rice cultivar under climate change is an important issue because the projected climate change has a potential to bring a negative impact on crop yield. In this study, we estimate an impact of climate change on rice yield and potential best cultivar in northern Japan where the larger paddy field is located than other regions in Japan. Two global climate model data, MIROC5 (RCP 4.5) and MRI-AGCM (SRES A1B), are applied as the future scenario. These data are too coarse to resolve the regional differences in northern Japan; we conduct the downscale experiments by a regional climate model (JMA-NHM) with a 10-km grid spacing. Considering that rice yield is sensitive to warm season climate, we conduct the downscaling from 28th May to 1st September during 1981-2000 and 2081-2099. The biases of downscaled two scenarios are corrected to match their cumulative distribution functions (CDF) of present climate with that of the station-based observation. The derived CDF-based biases are also used to correct the future scenarios. These corrected scenarios are applied to rice growth model (NIAES-Rice). To take account for the impacts of land use change (LUC) on climate and rice yield, we consider the additional temperature changes due to the LUC. As a reference, we add the LUC-induced temperature change in southwest Japan because the data are available from the previous study. We first check the climate change in northern Japan. General tendencies derived from the bias-corrected-downscaled future climates are that 1) surface warming was approximately twice in low elevation area relative to mountainous area and 2) downward shortwave radiation homogeneously increased 7-8 W m-2. Then, we evaluated the simulated yield through comparing with observation. Using observed ambient conditions as input data, the NIAES-Rice model provides the reasonable performance in simulating the rice yield with biases ranging from -19.0 to 29.2 % in prefecture base. Climate

  17. Impacts of Biomass Burning on the Land Use / Land Cover Dynamics in Northern Sub-Saharan Africa and Associated Alteration of Local Emission Rates

    NASA Astrophysics Data System (ADS)

    Ellison, L.; Ichoku, C. M.

    2015-12-01

    Biomass burning is a major anthropogenic event in Northern Sub-Saharan Africa (NSSA), which contributes 15-20% of the global annual total of particulate matter emissions from fires. This burning is mostly for agricultural, grazing or hunting purposes, and thus has a great potential for driving changes in the land use and land cover distribution in that region. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard both the Terra and Aqua spacecraft have two complimentary data products to support this research: the MOD14/MYD14 active fire products measuring fire locations and strengths, and the MCD12 land cover type product, which includes the International Geosphere Biosphere Programme (IGBP) land-cover classification system used in this analysis. More specifically, the MCD12Q1 tiled data product at 500 m was used to match against the 1 km active fire product resolution for the current analysis. Paired data between instantaneous fire measurements and the underlying land cover types for the particular year over the study period of 2003-2013 reveals a dominant burning of savanna, followed by cropland land cover type throughout the region. There are a few indications of the interchange between savanna and cropland due to burning practices. Even though the fire activity in the whole NSSA region is decreasing at a rate of 1.4%/yr during the study period, some land cover types in parts of NSSA show an increase, including local increases in sensitive land cover types such as forest and wetland, which could have serious ecological implications. The changes in the overall redistribution of biomass burning amongst the different land cover types in NSSA dictate that there is also a redistribution of biomass burning emissions. The extent of these changes will also be covered in this presentation.

  18. On the Main Factors Controlling Anthropogenic Land Subsidence in the Northern Plain of the Chaobai River, North Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhu, L.; Teatini, P.; Gong, H.; Ke, Y.; Pan, Y.

    2014-12-01

    Anthropogenic land subsidence is a widespread phenomenon threatening several cities in China. One major area of land subsidence is the Beijing city. The city continues to grow and unofficial estimates put the population at around 21-22 million in 2013, with an increase by 40% from 2000 to 2010. Along with the increasing urbanization, demands for water resources become larger. Approximately 2/3 of the water need is supplied by groundwater. To cope with the pressure for water supply, a first "over-sized emergency groundwater resource region (EGRR)" was built in 2003 at the Huairou district, where is the upper and middle plain of the Chaobai River, few tens km to the north of the metropolitan center. Other four EGRRwell-fields have been established in different districts surrounding the city in the next years. The long-time over-exploitation of groundwater resulted in water level fall and land subsidence. Persistent Scatterer Interferometry (PSI) on ENVISAT images has been used to detect land subsidence in the northern Beijing plain from 2003 to 2010. The PSI outcome, which was calibrated using ground-based measurements including levelling and extensometers, reveals that the largest subsidence rate reached 52 mm/yr, with a cumulative maximum sinking equal to 342 mm, in the Houshayu city at the southwestern part of the study area where the capital international airport is situated. Land subsidence in the northern zones, where the main well-fields are located, was much smaller in the order of 60 mm. Hydro-geologic investigations have showed that the distribution of groundwater depression cones only partially resembles the land subsidence pattern. The subsidence rates are strongly correlated with the distribution of compressible clay units. In the south-westernmost zone, at the bound of the metropolitan area, the cumulative thickness of cohesive soils amounts to 250 m in the upper 390 m sedimentary sequence. Conversely, sands and gravels prevail in the northern portion

  19. Using Poaching Levels and Elephant Distribution to Assess the Conservation Efficacy of Private, Communal and Government Land in Northern Kenya.

    PubMed

    Ihwagi, Festus W; Wang, Tiejun; Wittemyer, George; Skidmore, Andrew K; Toxopeus, Albertus G; Ngene, Shadrack; King, Juliet; Worden, Jeffrey; Omondi, Patrick; Douglas-Hamilton, Iain

    2015-01-01

    Efforts to curb elephant poaching have focused on reducing demand, confiscating ivory and boosting security patrols in elephant range. Where land is under multiple uses and ownership, determining the local poaching dynamics is important for identifying successful conservation models. Using 2,403 verified elephant, Loxodonta africana, mortality records collected from 2002 to 2012 and the results of aerial total counts of elephants conducted in 2002, 2008 and 2012 for the Laikipia-Samburu ecosystem of northern Kenya, we sought to determine the influence of land ownership and use on diurnal elephant distribution and on poaching levels. We show that the annual proportions of illegally killed (i.e., poached) elephants increased over the 11 years of the study, peaking at 70% of all recorded deaths in 2012. The type of land use was more strongly related to levels of poaching than was the type of ownership. Private ranches, comprising only 13% of land area, hosted almost half of the elephant population and had significantly lower levels of poaching than other land use types except for the officially designated national reserves (covering only 1.6% of elephant range in the ecosystem). Communal grazing lands hosted significantly fewer elephants than expected, but community areas set aside for wildlife demonstrated significantly higher numbers of elephants and lower illegal killing levels relative to non-designated community lands. While private lands had lower illegal killing levels than community conservancies, the success of the latter relative to other community-held lands shows the importance of this model of land use for conservation. This work highlights the relationship between illegal killing and various land ownership and use models, which can help focus anti-poaching activities. PMID:26407001

  20. Using Poaching Levels and Elephant Distribution to Assess the Conservation Efficacy of Private, Communal and Government Land in Northern Kenya

    PubMed Central

    Ihwagi, Festus W.; Wang, Tiejun; Wittemyer, George; Skidmore, Andrew K.; Toxopeus, Albertus G.; Ngene, Shadrack; King, Juliet; Worden, Jeffrey; Omondi, Patrick; Douglas-Hamilton, Iain

    2015-01-01

    Efforts to curb elephant poaching have focused on reducing demand, confiscating ivory and boosting security patrols in elephant range. Where land is under multiple uses and ownership, determining the local poaching dynamics is important for identifying successful conservation models. Using 2,403 verified elephant, Loxodonta africana, mortality records collected from 2002 to 2012 and the results of aerial total counts of elephants conducted in 2002, 2008 and 2012 for the Laikipia-Samburu ecosystem of northern Kenya, we sought to determine the influence of land ownership and use on diurnal elephant distribution and on poaching levels. We show that the annual proportions of illegally killed (i.e., poached) elephants increased over the 11 years of the study, peaking at 70% of all recorded deaths in 2012. The type of land use was more strongly related to levels of poaching than was the type of ownership. Private ranches, comprising only 13% of land area, hosted almost half of the elephant population and had significantly lower levels of poaching than other land use types except for the officially designated national reserves (covering only 1.6% of elephant range in the ecosystem). Communal grazing lands hosted significantly fewer elephants than expected, but community areas set aside for wildlife demonstrated significantly higher numbers of elephants and lower illegal killing levels relative to non-designated community lands. While private lands had lower illegal killing levels than community conservancies, the success of the latter relative to other community-held lands shows the importance of this model of land use for conservation. This work highlights the relationship between illegal killing and various land ownership and use models, which can help focus anti-poaching activities. PMID:26407001

  1. Soil organic carbon and land use in Veneto and Friuli Venezia Giulia (Northern Italy)

    NASA Astrophysics Data System (ADS)

    Francaviglia, Rosa; Renzi, Gianluca; Benedetti, Anna

    2014-05-01

    The Italian Ministry of Agricultural Food and Forestry Policies (MiPAAF) has set up a statistical survey aimed to provide the national forecast of yields and areas related to the main Italian agricultural crops (AGRIT). The methodology is based on field surveys and remote-sensed data, covers yearly the whole national territory, and is based on 100,000 observations which are statistically selected from a predefined grid made up of about 1,200,000 georeferenced points. In 2011-2012 we determined the soil organic carbon content (SOC) of 1,160 sampling points situated in Northern Italy in the plains and hills of Veneto (VEN) and Friuli Venezia Giulia (FVG), for which the land use in the period 2008-2010 was known. Samples have been subdivided in three main classes: arable crops, orchards and fodder crops. SOC was higher in FVG samples (2.48%, n=266) than in VEN samples (1.90%, n=894). The average value (2.03%) is clearly affected by the higher number of VEN samples. FVG data have been aggregated in continuous crops (maize, soybean, wheat), 2-yr rotations (maize-wheat, soybean wheat, maize-soybean), 3-yr rotations, vineyards (totally, partially and no-grassed), alfalfa, and permanent fodder crops. No significant differences were detected among the land uses due to the low number of samples in some classes, but some important findings do exist from the agronomic point of view. Fodder crops (5.65%), alfalfa (3.41%) and vineyards (2.72%) showed the higher SOC content. SOC was 2.94% and 1.39 % in the grassed and no-grassed vineyards respectively. In the arable crops the average SOC was 2.18%, ranging from 2.32% (soybean-wheat rotation) to 2.03% (continuous soybean). SOC was 2.19% in the continuous maize, with 2.23% in corn and 1.87% in silage maize. The lower values were in the maize-wheat rotation (1.53%) and the continuous wheat (1.47%). VEN data have been aggregated in continuous crops (maize, soybean and wheat), 2-yr rotations (maize-wheat, soybean-wheat, maize

  2. Proposed Mars Surveyor landing sites in northern Meridiani Sinus, southern Elysium Planitia, and Argyre Planitia

    NASA Astrophysics Data System (ADS)

    Parker, T. J.; Edgett, K. S.

    1998-01-01

    necessarily excludes from the present study images from current and future orbiter spacecraft, until such data does become readily available. Within each proposed region, it may be possible to identify additional sites once these data become available. Second, the fine-component thermal inertia data [1], compiled by P. Christensen and made available to the Mars Pathfinder project, should be greater than about 5 or 6 cgs units (10^-3 cal cm^-2 s^-0.5 K^-1). Low thermal inertias imply dusty environments, which could pose a mobility hazard. Similarly, the albedo ([2] digital file made available to the Mars Pathfinder project by P. Christensen) of the site should not be particularly high, which would also suggest dusty surfaces. Low albedos are preferred, as they often coincide with low Viking red:violet ratios and indicate less dusty surfaces. Next, the Modeled Block Abundance [1] should also not bee too high or too low. Based on the Viking Lander and Mars Pathfinder experiences, percentages of blocks should be on the order of 5-22%. Too many blocks could pose a hazard to the landing and mobility. Too few blocks could also indicate a dusty surface. Primary Landing Site: Northern Meridiani Sinus (Proposed by T. J. Parker and K. S. Edgett) Vital Statistics: *Latitude, Longitude: 0-3°N, 350-2°W. *Elevation (Viking): ~0.5-1.5 km. *Viking Orbiter Image coverage: Excellent coverage by 15-25 m/pixel images (orbits 709A and 410B). Possible stereo coverage in region where two orbits overlap (probably small parallax angle, as these orbits are not listed in NASA Contractor Report 3501) *Albedo: ~0.18-0.26 *Block Abundance: 5-26% *Fine-Component Thermal Inertia: 5-9 cgs units This region consists of bright deposits similar to those described by Edgett et al. [3], that also lie within a prominent dark albedo region. These deposits are flat-lying, to such a degree that they ramp against topography rather than draping over it. This led Edgett and Parker [4] to suggest that they may be

  3. Geomorphology of the 2007 Phoenix Mission Landing Sites in the Northern Plains of Mars

    NASA Astrophysics Data System (ADS)

    Seelos, K. D.; Arvidson, R. E.; Golombek, M.; Parker, T.; Tamppari, L.; Smith, P.

    2005-12-01

    In 2008, the Phoenix lander will touch down in the northern plains of Mars to sample and characterize near surface and underlying ice-rich soils, gather meteorological data, and provide insight into the evolution of the surrounding landscape. Three regions from 65 to 72 N and (A) 250-270E, (B) 120-140E, and (C) 65-85E that meet both engineering and scientific constraints were chosen for concentrated acquisition of remote data to support landing site selection. Smaller areas (150x75 km) within these regions devoid of large craters or other hazards were selected as potential landing sites; center coordinates for these targeted areas are (A) 68N, 260E, (B) 67.5N, 130E, and (C) 70N, 80E. MOLA topographic data along with MOC imagery and THEMIS 36m/pixel visible, 18m/pixel visible, and ~100m/pixel infrared data are utilized to produce geomorphologic maps at 36m/pixel for the larger regions and 18m/pixel for the targeted sites. All regions are dominated by intercrater plains units, with the plains in regions B and C comprised of slightly elevated, multiple kilometer-scale polygonal blocks surrounded or infilled by finer-grained material. The plains unit of region A lacks large polygons, instead exhibiting a smooth to mottled appearance. Patterned ground is ubiquitous throughout all regions. The characteristic dimpled texture of "basketball" terrain is most common, being superposed on the large polygons in regions B and C, and often organized into stripes with orientations partially controlled by local slopes. Small-scale polygonal ground is also observed usually in association with crater ejecta. Craters throughout all regions appear highly degraded, with most small craters (< 1km) remarkably worn with little or no rim definition and ejecta present only as a faint dark halo. Larger craters frequently exhibit pedestal-style ejecta. The style and state of landform degradation and the consistent presence of patterned ground throughout all regions suggests the long

  4. Paleozoic magmatism and associated tectonic problems of northern Victoria Land, Antarctica

    NASA Astrophysics Data System (ADS)

    Borg, S. G.; Stump, E.

    The division of northern Victoria Land (NVL) into three north-northwest trending terranes is underscored by recent chemical and isotopic studies of the Paleozoic granitoids of the region. Early Paleozoic Granite Harbour Intrusives are found only in the (western) Wilson Terrane (WT), best interpreted as a continuation of the Ross Orogenic Belt, which developed along the margin of the East Antarctic Craton. Devonian Admiralty Intrusives, however, are found only within the (central) Bowers Terrane (BT) and the (eastern) Robertson Bay Terrane (RBT), and studies of chemical polarity indicate that these terranes are fragments of an allochthonous crustal block. In view of the key position occupied by NVL in reconstructions of Antarctica and Australia, recognition of the relationships outlined above raises important questions about the assembly and perhaps the breakup of this portion of Gondwana. Timing of juxtapositioning of the BT+RBT against the WT is problematic but is thought to have occurred after emplacement of the Devonian Admiralty Intrusives and must have occurred prior to deposition of the Beacon Supergroup in the Permian. Other geologic relations known at present do not provide definitive constraints on tectonic models, but there are unresolved points which may have special significance. For example, the tectonic setting of the Salamander Granite Complex, as well as the tectonic setting of middle Paleozoic volcanics exposed at Mount Black Prince, Lawrence Peaks, and Gallipoli Heights remain an important question. Clearly, the geology of NVL holds important clues to the tectonic history of this segment of Gondwana. Continued studies of the granitoids, coupled with new research on the middle Paleozoic volcanics, detailed structural studies with emphasis on timing and sense of movement on the terrane bounding faults, and more detailed provenance studies of all the sedimentary and metasedimentary rock units in NVL, would be helpful in evaluating and revising

  5. Metasomatism vs Refertilisation: New Insights from Northern Victoria Land mantle xenoliths (Antarctica)

    NASA Astrophysics Data System (ADS)

    Pelorosso, Beatrice; Bonadiman, Costanza; Coltorti, Massimo; Ntaflos, Theodoros; Gregoire, Michel

    2016-04-01

    The petrology of anhydrous (Greene Point, Handler Ridge) and amphibole-bearing (Harrow Peaks, Baker Rocks) xenolith populations from Cenozoic volcanics of Northern Victoria Land (NVL), Antarctica, provide new geochemical/geodynamic constraints on the nature and evolution of the NVL lithospheric mantle. Based on mineral major and trace element modelling applied on the various xenolith suites, this mantle domain is supposed to represent a residuum after 10 to 20% of partial melting, with Handler Ridge showing the most fertile character. Moreover, melting models and isotopic results evidence the large geochemical contribution of melt infiltration acting in different times, from at least Jurassic to Cenozoic. The close correlation between Greene Point clinopyroxene trace element contents and those from phenocrysts of Ferrar tholeiites, allows to ascribe the first refertilisation event to the Jurassic Ferrar magmatism; this asthenospheric melt was also able to transfer a garnet signature to some NVL mantle segment. The rare presence of glassy patches and related secondary phases in Greene Point and Handler Ridge, as well as the amphibole presence in Harrow Peaks and Baker Rocks xenoliths prove that alkaline metasomatism, probably related to the West Antarctic Rift System opening, heterogeneously affected the NVL lithospheric domain. At a fixed P of 15 Kbar, T and fO2 were calculated; data reveal that the presence of amphibole (always < 3% modal content) does not influence the ambient redox conditions (comparable in amphibole-bearing and anhydrous Greene Point peridotites [ Δlog fO2 (QFM) -0.7)] but the anhydrous suite presents systematic higher temperature (950-1050 °C) than those amphibole bearing (850 °C).

  6. [Home food services for the elderly: the consumer and his appreciation of a warm meal service in Arnhem].

    PubMed

    Sneeuw, K C; Stam, P G; de Graaf, C; van Staveren, W A

    1991-02-01

    An important instrument to achieve prolonged independence of elderly is the provision of meals, in particular cooked meals at home. The purpose of the present study is an evaluation from the consumers perspective of a meals-on-wheels service in Arnhem. Furthermore, the 77 meals-on-wheels consumers in this study, all making intensive use of the service, are described and compared to a representative sample of elderly. The participants appeared to be vulnerable from the perspective of health (particularly the women) and social situation. The perceived quality of both meals and service seem to be high. The taste, the quality of the meat and the first impression of the meal are important determinants of overall perceived meal quality. Responsiveness and reliability have a significant contribution to perceived service quality. PMID:1877070

  7. Land-use change reduces habitat suitability for supporting managed honey bee colonies in the Northern Great Plains.

    PubMed

    Otto, Clint R V; Roth, Cali L; Carlson, Benjamin L; Smart, Matthew D

    2016-09-13

    Human reliance on insect pollination services continues to increase even as pollinator populations exhibit global declines. Increased commodity crop prices and federal subsidies for biofuel crops, such as corn and soybeans, have contributed to rapid land-use change in the US Northern Great Plains (NGP), changes that may jeopardize habitat for honey bees in a part of the country that supports >40% of the US colony stock. We investigated changes in biofuel crop production and grassland land covers surrounding ∼18,000 registered commercial apiaries in North and South Dakota from 2006 to 2014. We then developed habitat selection models to identify remotely sensed land-cover and land-use features that influence apiary site selection by Dakota beekeepers. Our study demonstrates a continual increase in biofuel crops, totaling 1.2 Mha, around registered apiary locations in North and South Dakota. Such crops were avoided by commercial beekeepers when selecting apiary sites in this region. Furthermore, our analysis reveals how grasslands that beekeepers target when selecting commercial apiary locations are becoming less common in eastern North and South Dakota, changes that may have lasting impact on pollinator conservation efforts. Our study highlights how land-use change in the NGP is altering the landscape in ways that are seemingly less conducive to beekeeping. Our models can be used to guide future conservation efforts highlighted in the US national pollinator health strategy by identifying areas that support high densities of commercial apiaries and that have exhibited significant land-use changes. PMID:27573824

  8. Land-use change reduces habitat suitability for supporting managed honey bee colonies in the Northern Great Plains

    USGS Publications Warehouse

    Otto, Clint R.; Roth, Cali; Carlson, Benjamin; Smart, Matthew

    2016-01-01

    Human reliance on insect pollination services continues to increase even as pollinator populations exhibit global declines. Increased commodity crop prices and federal subsidies for biofuel crops, such as corn and soybeans, have contributed to rapid land-use change in the US Northern Great Plains (NGP), changes that may jeopardize habitat for honey bees in a part of the country that supports >40% of the US colony stock. We investigated changes in biofuel crop production and grassland land covers surrounding ∼18,000 registered commercial apiaries in North and South Dakota from 2006 to 2014. We then developed habitat selection models to identify remotely sensed land-cover and land-use features that influence apiary site selection by Dakota beekeepers. Our study demonstrates a continual increase in biofuel crops, totaling 1.2 Mha, around registered apiary locations in North and South Dakota. Such crops were avoided by commercial beekeepers when selecting apiary sites in this region. Furthermore, our analysis reveals how grasslands that beekeepers target when selecting commercial apiary locations are becoming less common in eastern North and South Dakota, changes that may have lasting impact on pollinator conservation efforts. Our study highlights how land-use change in the NGP is altering the landscape in ways that are seemingly less conducive to beekeeping. Our models can be used to guide future conservation efforts highlighted in the US national pollinator health strategy by identifying areas that support high densities of commercial apiaries and that have exhibited significant land-use changes.

  9. Characterization of land surface energy fluxes at the Salar de Atacama, Northern Chile using ASTER image classification

    NASA Astrophysics Data System (ADS)

    Kampf, S. K.; Tyler, S. W.

    2003-12-01

    Models of land surface energy fluxes often use remotely sensed data to derive surface temperature, albedo, and emissivity, important parameters in energy budget calculations. The ability to determine the spatial distribution of these parameters can lead to improved estimations of the spatial variability of land surface energy fluxes. However, other parameters used in energy flux calculations such as aerodynamic resistance are not directly linked to quantities commonly derived from remotely sensed data. If images can be accurately classified into separate land cover types, empirically determined values of unknown parameters can then be assigned separately to each land cover classification. This study examines several techniques of determining the spatial distribution of land surface energy fluxes at the Salar de Atacama, a large playa in northern Chile. Fluxes are calculated using Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) Level 2 surface kinetic temperature, surface emissivity, and surface reflectance data in conjunction with ground-based meteorological measurements. Energy fluxes are calculated initially by applying a single value of aerodynamic resistance to the entire image area. Subsequently, the ASTER scene is classified into distinct land cover types, and land surface roughness is characterized using the ratio of ASTER band 3N (nadir-viewing) to band 3B (back-viewing). Separate values of aerodynamic resistance are then assigned to each land cover type, and energy fluxes over the entire Salar de Atacama are calculated using these spatially distributed aerodynamic resistance values. Results of both energy flux calculation techniques are evaluated at several sites on the playa using ground-based energy flux measurements.

  10. Examining soil erosion and nutrient accumulation in forested and agriculture lands of the low mountainous area of Northern Vietnam

    NASA Astrophysics Data System (ADS)

    Pham, A. T.; Gomi, T.; Takahisa, F.; Phung, K. V.

    2011-12-01

    We examined soil erosion and nutrient accumulations in the Xuanmai area located in the low mountainous region of Northern Vietnam, based on field investigations and remote sensing approaches. The study area had been degraded by land-use change from forest to agriculture in the last 20 years. In contrast, around the study area, the Vietnam government promoted reforestation projects. Such changes in land-use conditions, which may or may not be associated with vegetation ground cover conditions, potentially alter soil erosion and nutrient accumulation. We selected 10 dominant land-use types including forested land (e.g., Pinus massoniana and Acacia mangium plantation) agriculture land (e.g., Cassava), and bare land. We established three 1 x 1 m plots in each land-use type in September 2010. Vegetation biomass, litter cover, soil erosion (height of soil pedestal), and soil physical (soil bulk density and particle size distribution) and chemical properties (Total soil carbon, nitrate, and phosphorus) were measured. Height of soil pedestal can be a record of soil erosion by rain splash during rainy periods from April to August (prior to our field study). We also conducted remote sensing analysis using Landsat TM images obtained in 1993, 2000, and 2007 for identifying temporal patterns of land-use types. We found that the intensity of soil erosion depended primary on current vegetation ground cover condition with no regard of land-use. Hence, nutrient accumulation varied among vegetation ground cover and soil erosion. Remote sensing analysis suggested that shrub and bare lands had been altered from forested land more recently. Our finding suggested that variability of soil nutrient conditions can be associated with long-term soil erosion and production processes. Findings of our study are that: (1) current vegetation and litter ground cover affected the amount of surface soil erosion, and (2) legacy of land-use can be more critical for soil nutrient accumulation. Both

  11. Importance of soil thermal dynamics on land carbon sequestration in Northern Eurasia during the 21st century

    NASA Astrophysics Data System (ADS)

    Kicklighter, David; Monier, Erwan; Sokolov, Andrei; Zhuang, Qianlai; Melillo, Jerry

    2015-04-01

    Recent modeling studies have suggested that carbon sinks in pan-arctic ecosystems may be weakening partially as a result of warming-induced increases in soil organic matter (SOM) decomposition and the exposure of previously frozen SOM to decomposition. This weakening of carbon sinks is likely to continue in the future as vast amount of carbon in permafrost soils is vulnerable to thaw. Here, we examine the importance of considering soil thermal dynamics when determining the effects of climate change and land-use change on carbon dynamics in Northern Eurasia during the 21st century. This importance is assessed by comparing results for a "business as usual" scenario between a version of the Terrestrial Ecosystem Model that does not consider soil thermal dynamics (TEM 4.4) and a version that does consider these dynamics (TEM 6.0). In this scenario, which is similar to the IPCC Representative Concentration Pathways (RCP) 8.5 scenario, the net area covered by food crops and pastures in Northern Eurasia is assumed to remain relatively constant over the 21st century, but the area covered by secondary forests is projected to double as a result of timber harvest and the abandonment of land associated with displacement of agricultural land. Enhanced decomposition from the newly exposed SOM from permafrost thaw also increases nitrogen availability for plant production so that the loss of carbon from the enhanced decomposition is partially compensated by enhanced uptake and storage of atmospheric carbon dioxide in vegetation. Our results indicate that consideration of soil thermal dynamics have a large influence on how simulated terrestrial carbon dynamics in Northern Eurasia respond to changes in climate, atmospheric chemistry (e.g., carbon dioxide fertilization, ozone pollution, nitrogen deposition) and disturbances.

  12. Spatial characterization of land surface energy fluxes and uncertainty estimation at the Salar de Atacama, Northern Chile

    NASA Astrophysics Data System (ADS)

    Kampf, Stephanie K.; Tyler, Scott W.

    2006-02-01

    We use Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) data to estimate spatial energy flux and evaporation distributions at the Salar de Atacama, a playa in Northern Chile. Our approach incorporates ASTER surface kinetic temperature, emissivity, and reflectance data, ground-based meteorological measurements, and empirical parameters. Energy flux distributions are estimated using either spatially constant or spatially distributed values of model parameters, with spatially distributed parameters assigned separately to each land cover category in an image classification. We test the sensitivity of energy budget calculations to state variable and parameter values by conducting Monte Carlo simulations for regions with ground energy budget measurements. Results show that assigning spatially distributed model parameters via land cover classifications yields significant improvements to ground and sensible heat flux predictions. Latent heat fluxes cannot, however, be predicted with sufficient accuracy to allow estimation of area-integrated evaporative moisture loss at this low-evaporation playa.

  13. Water-gas dynamics and coastal land subsidence over Chioggia Mare field, northern Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Baú, Domenico; Gambolati, Giuseppe

    2000-09-01

    A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company. One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth of 1000-1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing a rebound of 0.6-0.7 cm. Résumé. Un important programme de développement portant sur 15 gisements de gaz du nord de l'Adriatique a été récemment soumis au Comité VIA pour l'évaluation de l'impact sur l'environnement du Ministère de l'Environnement, par la société ENI-Agip, la compagnie nationale pétrolière italienne. L'un des plus importants réservoirs est celui de Chioggia Mare, situé à environ 10 km au large du littoral vénitien, à une profondeur de 1000 à 1400 m. La production de gaz prévue pour ce gisement laisse envisager un impact sur la stabilité du trait de côte, avec une

  14. Geomorphologic and mineralogic characterization of the northern plains of Mars at the Phoenix Mission candidate landing sites

    NASA Astrophysics Data System (ADS)

    Seelos, K. D.; Arvidson, R. E.; Cull, S. C.; Hash, C. D.; Heet, T. L.; Guinness, E. A.; McGuire, P. C.; Morris, R. V.; Murchie, S. L.; Parker, T. J.; Roush, T. L.; Seelos, F. P.; Wolff, M. J.

    2008-09-01

    A suite of remote sensing data is used to evaluate both geomorphology and mineralogy of the candidate landing sites for the 2007 Phoenix Mission. Three candidate landing site boxes are situated in the northern plains of Mars on the distal flank of Alba Patera in the region from 67°N to 72°N and from ~230°E to 260°E. Geomorphology is mapped at subkilometer spatial scales using Thermal Emission Imaging System (THEMIS) visible and Mars Orbiter Laser Altimeter (MOLA) topographic data, supplemented by images from the High-Resolution Imaging Science Experiment (HiRISE) and Context Imager (CTX). Mineralogy and spectral properties are examined using Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) visible and near-infrared multispectral mapping and targeted hyperspectral data at ~200 and ~20 m/pixel, respectively. Geomorphic mapping supports the idea that terrains along the boundary between the Amazonian Scandia region and Vastitas Borealis marginal geologic units have undergone extensive modification. Intercrater plains are disrupted to form mesas and interlocking blocks, while irregular depressions and knobby terrain are consistent with erosion/subsidence and local deposition. Despite the varied morphology, the present-day surface is nearly homogeneous with spectral signatures dominated by nanophase iron oxides and basaltic sand and rocks, similar to that of the Gusev crater plains at the Mars Exploration Rover (MER) landing site. The compilation of geomorphic and spectral information for the candidate Phoenix landing sites provides a framework for the mission's in situ observations to be extrapolated to the northern plains as a whole.

  15. Petrological characterization of mantle xenoliths from Handler Ridge, Northern Victoria Land (Antarctica)

    NASA Astrophysics Data System (ADS)

    Pelorosso, Beatrice; Bonadiman, Costanza; Coltorti, Massimo; Giacomoni, Pier Paolo

    2014-05-01

    A study of ultramafic xenoliths in Cenozoic alkali basalts from Handler Ridge has been carried out in order to characterize the petrological features of the lithospheric mantle beneath Handler Ridge, Northern Victoria Land (NVL) and to extend the petrological knowledge of the mantle over a large portion of the Western Antarctic Rift, from M.te Melbourne (74°21'S 164°42'E) to Handler Ridge (72°31'S 167°18'E). Xenoliths are anhydrous spinel(sp) bearing lherzolites. Two textural types were recognized: i) medium to coarse grain protogranular and ii) fine grain equigranular. Some xenoliths present evidences of peridotite-melt interactions, such as spongy textures, cloudy rims and glassy patches. Large primary sp are often lobated. Newly formed, secondary crystals are referred to cpx only. Regardless textural types, olivine (ol) is forsteritic in composition with Fo varying from 87.5 to 91.0, with a more fertile group ranging between 87.6 and 88.6. NiO contents between 0.31 and 0.44 wt% match the typical mantle values. As observed in ol, orthopyroxene (opx) can be distinguished in two clusters: the more fertile group with mg# [=Mg/(Mg+Fe)*100 mol] ranging between 87.6 and 88.3 and the more residual one with mg# from 88.9 to 91.0. In cpx mg# varies between 87.06 and 91.7. Cpx in depleted lherzolite and secondary cpx are characterized by high values of Na2O (1.3-1.63 wt%) and Al2O3 (4.62-6.62 wt%). Glasses are SiO2 (≥55.50 wt%) oversaturated with TiO2 content between 0.6 and 1wt% and Na2O/K2O in the range of 0.80-2.02. Sp are characterized by mg# values between 62 and 78, and cr# [=Cr/(Cr+Al)*100 mol] from 14 to 42 with the usual negative correlation between the two parameters. The relationship between ol, opx and sp suggest that partial melting is the main process controlling the chemical variation of these three phases, while cpx were affected by metasomatic event/s. On the basis of the formalism of Brey & Kohler (1990), Liermann & Ganguly (2003) and Ballhaus (1991

  16. Petrological study of Greene Point mantle xenoliths, Northern Victoria Land, Antarctica.

    NASA Astrophysics Data System (ADS)

    Pelorosso, Beatrice; Bonadiman, Costanza; Faccini, Barbara; Coltorti, Massimo; Ntaflos, Theodoros; Grégoire, Michel

    2015-04-01

    A petrological study of mantle, anhydrous spinel-bearing lherzolites and harzburgites from Greene Point (GP) (Northern Victoria Land, NVL) have been carried out. Texturally they vary from protogranular to porphyroclastic with large orthopyroxene (opx) and olivine (ol) grains. Clinopyroxene (cpx) is smaller and often associated with vermicular and lobated spinel (sp). Several types of reaction textures occur with secondary phases represented by olivine (ol2), clinopyroxene (cpx2), cpx with spongy rim, and glass. Ol in lherzolites presents lower forsteritic content (90.5-91.7) than in harzburgites (Fo: 91.6-92.3), but for three samples with an anomalously high Fo contents (92.3-92.7). Irrespective of lithology NiO contents are on the average ~0.38 wt%. Opx, equilibrated with ol1, has mg# (Mg/(Mg+Fe)*100mol) values ranging from 91.0 to 92.6 with the highest values found in harzburgites. As for Ol, however three lherzolitic samples have mg# in opx overlapping the most residual harzburgites; Al2O3 varies from 2.33 to 4.92 wt% following a residual trend. Opx is characterized by fractionated REE-chondrite normalized patterns, depleted in light REE (LREE), with the most residual character in harzburgites. Cpx1 has mg# varying from 91.5 to 93.9, with cpx in harzburgites presenting the highest values. As for the other two phases, cpx in three lherzolites presents mg# values comparable with those of harzburgites. Al2O3 contents is between 4.00 and 6.42 wt% in lherzolites and from 2.32 to 4.37 wt% in harzburgites. TiO2 never exceeds 0.66 wt%. Cpx in lherzolites are usually depleted in Th, U, Nb, and Ta with Ti, Zr and Hf negative anomalies. They present a REE patterns variable from slightly LREE-enriched (with La and Ce inflections) to LREE-depleted with a general convex-upward trend. This latter trend is related to mg# rich lherzolites. In harzburgites cpx show the lowest HREE contents (YbN 1.00-2.94), with a strong positive fractionated L-MREE and flat HREE. Sp1 show a

  17. Diagnosing the seasonal land-atmosphere correspondence over northern Australia: dependence on soil moisture state and correspondence strength definition

    NASA Astrophysics Data System (ADS)

    Decker, M.; Pitman, A.; Evans, J.

    2015-08-01

    The similarity of the temporal variations of land and atmospheric states during the onset (September) through to the peak (February) of the wet season over northern Australia is statistically diagnosed using ensembles of offline land surface model simulations that produce a range of different background soil moisture states. We derive the temporal correspondence between variations in the soil moisture and the planetary boundary layer via a statistical measure of rank correlation. The simulated evaporative fraction and the boundary layer are shown to be strongly correlated during both SON (September-October-November) and DJF (December-January-February) despite the differing background soil moisture states between the two seasons and among the ensemble members. The sign and magnitude of the boundary layer-surface layer soil moisture association during the onset of the wet season (SON) differs from the correlation between the evaporative fraction and boundary layer from the same season, and from the correlation between the surface soil moisture and boundary layer association during DJF. The patterns and magnitude of the surface flux-boundary layer correspondence are not captured when the relationship is diagnosed using the surface layer soil moisture alone. The conflicting results arise because the surface layer soil moisture lacks strong correlation with the atmosphere during the monsoon onset because the evapotranspiration is dominated by transpiration. Our results indicate that accurately diagnosing the correspondence and therefore coupling strength in seasonally dry regions, such as northern Australia, requires root zone soil moisture to be included.

  18. Desertification triggered by hydrological and geomorphological processes and palaeoclimatic changes in the Hunshandake Sandy Lands, Inner Mongolia, northern China

    NASA Astrophysics Data System (ADS)

    Yang, X.; Scuderi, L. A.; Wang, X.; Zhang, D.; Li, H.; Forman, S. L.

    2015-12-01

    Although Pleistocene and earlier aeolian sediments in the adjacent regions of deserts were used as indicators for the occurrence of the deserts in northern China, our multidisciplinary investigation in the Hunshandake Sandy Lands, Inner Mongolia, a typical landscape in the eastern portion of the Asian mid-latitude desert belt, demonstrates that this sandy desert is just ca. 4000 years old. Before the formation of the current sand dunes, Hunshandke was characterized with large and deep lakes and grasssland vegetation, as many sedimentary sections indicate. Optically Stimulated Luminescence (OSL) chronology shows that the three large former lakes where we have done detailed investigation, experienced high stands from early Holocene to ca. 5 ka. During the early and middle Holocene this desert was a temperate steppe environment, dominated by grasslands and trees near lakes and streams, as various palaeoenvironmental proxies suggest. While North Hemisphere's monsoonal regions experienced catastrophic precipitation decreases at ca. 4.2 ka, many parts of the presently arid and semi-arid zone in northern China were shifted from Green to Desert state. In the eastern portion of the Hunshandake, the desertification was, however, directly associated with groundwater capture by the Xilamulun River, as the palaeo-drainage remains show. The process of groundwater sapping initiated a sudden and irreversible region-wide hydrologic event that lowered the groundwater table and exacerbated the desertification of the Hunshandake, and further resulting in post-Humid period mass migration of northern China's Hongshan culture from that we think the modern Chinese civilization has been rooted.

  19. Water-gas dynamics and coastal land subsidence over Chioggia Mare field, northern Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Baú, Domenico; Gambolati, Giuseppe

    2000-09-01

    A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company. One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth of 1000-1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing a rebound of 0.6-0.7 cm. Résumé. Un important programme de développement portant sur 15 gisements de gaz du nord de l'Adriatique a été récemment soumis au Comité VIA pour l'évaluation de l'impact sur l'environnement du Ministère de l'Environnement, par la société ENI-Agip, la compagnie nationale pétrolière italienne. L'un des plus importants réservoirs est celui de Chioggia Mare, situé à environ 10 km au large du littoral vénitien, à une profondeur de 1000 à 1400 m. La production de gaz prévue pour ce gisement laisse envisager un impact sur la stabilité du trait de côte, avec une

  20. Trade-off analysis in the Northern Andes to study the dynamics in agricultural land use.

    PubMed

    Stoorvogel, J J; Antle, J M; Crissman, C C

    2004-08-01

    In this paper we hypothesize that land use change can be induced by non-linearities and thresholds in production systems that impact farmers' decision making. Tradeoffs between environmental and economic indicators is a useful way to represent dynamic properties of agricultural systems. The Tradeoff Analysis (TOA) System is software designed to implement the integrated analysis of tradeoffs in agricultural systems. The TOA methodology is based on spatially explicit econometric simulation models linked to spatially referenced bio-physical simulation models to simulate land use and input decisions. The methodology has been applied for the potato-pasture production system in the Ecuadorian Andes. The land use change literature often describes non-linearity in land use change as a result of sudden changes in the political (e.g. new agricultural policies) or environmental setting (e.g. earthquakes). However, less attention has been paid to the non-linearities in production systems and their consequences for land use change. In this paper, we use the TOA system to study agricultural land use dynamics and to find the underlying processes for non-linearities. Results show that the sources of non-linearities are in the properties of bio-physical processes and in the decision making-process of farmers. PMID:15246571

  1. Complex land use and cover trajectories in the northern Choco bioregion of Colombia

    NASA Astrophysics Data System (ADS)

    Santos, Carolina

    The Choco bioregion in Northwestern Colombia is a lowland rain forest and hotspot of biodiversity. Significant land use and cover change (LUCC) is occurring throughout the region driven by global markets, illicit drug production, and civil unrest. The dominant land cover conversion is from primary forest to African Palm plantations, mediated and modified by complex combinations of social and biophysical drivers. This research combined a remote sensing based methodology to monitor LUCC in the region with an analytical approach for evaluating the possible trajectories of LUCC in a complex biological, socio-economical, and political environment. Synoptic LUCC models were developed using textural classification derived from Synthetic Aperture Radar (SAR) images for the period 1995 to 2010. LUCC models along with empirical social and spatial biophysical drivers were used to project historical land use trajectories. DINAMICA EGO a complex systems based spatial analytical framework was adopted as the platform to model land use change. The RADAR backscatter was able to capture areas were forest has been converted to African Oil Palm Plantations. However, an in depth characterization of the LUC dynamics was problematic given the spectral and spatial limitations of the sensor combined with the lack of ground data. The results of the LUC model suggest that under the current socio-political conditions African oil palm plantations will continue to expand toward forested areas into the territories traditionally inhabited by Afro-Colombians and Indigenous populations. Insecure land tenure appears as a main driver of the transformation in close association with the conditions created by the armed conflict, and the drug traffic. The rate of the transformation appears to slow down in the period after 2007. However, according to the model by 2020 most of the area inhabited by ethnic groups will be transform to AOP. This study contributes towards the understanding of land use change

  2. Remote sensing of soils, land forms, and land use in the northern Great Plains in preparation for ERTS applications

    NASA Technical Reports Server (NTRS)

    Frazee, C. J.; Westin, F. C.; Gropper, J.; Myers, V. I.

    1972-01-01

    Research to determine the optimum time or season for obtaining imagery to identify and map soil limitations was conducted in the proposed Oahe irrigation project area in South Dakota. The optimum time for securing photographs or imagery is when the soil surface patterns are most apparent. For cultivated areas similar to the study area, May is the optimum time. The density slicing analysis of the May image provided additional and more accurate information than did the existing soil map. The soil boundaries were more accurately located. The use of a density analysis system for an operational soil survey has not been tested, but is obviously dependent upon securing excellent photographs for interpretation. The colors or densities of photographs will have to be corrected for sun angle effects, vignetting effects, and processing to have maximum effectiveness for mapping soil limitations. Rangeland sites were established in Bennett County, South Dakota to determine the usefulness of ERTS imagery. Imagery from these areas was interpreted for land use and drainage patterns.

  3. Satellite observations of changes in snow-covered land surface albedo during spring in the Northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Atlaskina, K.; Berninger, F.; de Leeuw, G.

    2015-05-01

    Thirteen years of MODIS surface albedo data for the Northern Hemisphere during the spring months (March-May) were analysed to determine temporal and spatial changes over snow-covered land surfaces. Tendencies in land surface albedo change north of 50° N were analysed using data on snow cover fraction, air temperature, vegetation index and precipitation. To this end, the study domain was divided into six smaller areas, based on their geographical position and climate similarity. Strong differences were observed between these areas. As expected, snow cover fraction (SCF) has a strong influence on the albedo in the study area and can explain 56% of variation of albedo in March, 76% in April and 92% in May. Therefore the effects of other parameters were investigated only for areas with 100% SCF. The second largest driver for snow-covered land surface albedo changes is the air temperature when it exceeds -15 °C. At monthly mean air temperatures below this value no albedo changes are observed. Enhanced vegetation index (EVI) and precipitation amount and frequency were independently examined as possible candidates to explain observed changes in albedo for areas with 100% SCF. Amount and frequency of precipitation were identified to influence the albedo over some areas in Eurasia and North America, but no clear effects were observed in other areas. EVI is positively correlated with albedo in Chukotka Peninsula and negatively in Eastern Siberia. For other regions the spatial variability of the correlation fields is too high to reach any conclusions.

  4. Aboveground and belowground legacies of native Sami land use on boreal forest in northern Sweden 100 years after abandonment.

    PubMed

    Freschet, Grégoire T; Ostlund, Lars; Kichenin, Emilie; Wardle, David A

    2014-04-01

    Human activities that involve land-use change often cause major transformations to community and ecosystem properties both aboveground and belowground, and when land use is abandoned, these modifications can persist for extended periods. However, the mechanisms responsible for rapid recovery vs. long-term maintenance of ecosystem changes following abandonment remain poorly understood. Here, we examined the long-term ecological effects of two remote former settlements, regularly visited for -300 years by reindeer-herding Sami and abandoned -100 years ago, within an old-growth boreal forest that is considered one of the most pristine regions in northern Scandinavia. These human legacies were assessed through measurements of abiotic and biotic soil properties and vegetation characteristics at the settlement sites and at varying distances from them. Low-intensity land use by Sami is characterized by the transfer of organic matter towards the settlements by humans and reindeer herds, compaction of soil through trampling, disappearance of understory vegetation, and selective cutting of pine trees for fuel and construction. As a consequence, we found a shift towards early successional plant species and a threefold increase in soil microbial activity and nutrient availability close to the settlements relative to away from them. These changes in soil fertility and vegetation contributed to 83% greater total vegetation productivity, 35% greater plant biomass, and 23% and 16% greater concentrations of foliar N and P nearer the settlements, leading to a greater quantity and quality of litter inputs. Because decomposer activity was also 40% greater towards the settlements, soil organic matter cycling and nutrient availability were further increased, leading to likely positive feedbacks between the aboveground and belowground components resulting from historic land use. Although not all of the activities typical of Sami have left visible residual traces on the ecosystem after

  5. Hydrometeorological effects of historical land-conversion in an ecosystem-atmosphere model of Northern South America

    NASA Astrophysics Data System (ADS)

    Knox, R. G.; Longo, M.; Swann, A. L. S.; Zhang, K.; Levine, N. M.; Moorcroft, P. R.; Bras, R. L.

    2015-01-01

    This work investigates how the integrated land use of northern South America has affected the present day regional patterns of hydrology. A model of the terrestrial ecosystems (ecosystem demography model 2: ED2) is combined with an atmospheric model (Brazilian Regional Atmospheric Modeling System: BRAMS). Two realizations of the structure and composition of terrestrial vegetation are used as the sole differences in boundary conditions that drive two simulations. One realization captures the present day vegetation condition that includes deforestation and land conversion, the other is an estimate of the potential structure and composition of the region's vegetation without human influence. Model output is assessed for differences in resulting hydrometeorology. The simulations suggest that the history of land conversion in northern South America is not associated with a significant precipitation bias in the northern part of the continent, but has shown evidence of a negative bias in mean regional evapotranspiration and a positive bias in mean regional runoff. Also, negative anomalies in evaporation rates showed pattern similarity with areas where deforestation has occurred. In the central eastern Amazon there was an area where deforestation and abandonment had lead to an overall reduction of above-ground biomass, but this was accompanied by a shift in forest composition towards early successional functional types and grid-average-patterned increases in annual transpiration. Anomalies in annual precipitation showed mixed evidence of consistent patterning. Two focus areas were identified where more consistent precipitation anomalies formed, one in the Brazilian state of Pará where a dipole pattern formed, and one in the Bolivian Gran Chaco, where a negative anomaly was identified. These locations were scrutinized to understand the basis of their anomalous hydrometeorologic response. In both cases, deforestation led to increased total surface albedo, driving decreases

  6. Comparison of Hyperspectral and Multispectral Satellites for Discriminating Land Cover in Northern California

    NASA Astrophysics Data System (ADS)

    Clark, M. L.; Kilham, N. E.

    2015-12-01

    Land-cover maps are important science products needed for natural resource and ecosystem service management, biodiversity conservation planning, and assessing human-induced and natural drivers of land change. Most land-cover maps at regional to global scales are produced with remote sensing techniques applied to multispectral satellite imagery with 30-500 m pixel sizes (e.g., Landsat, MODIS). Hyperspectral, or imaging spectrometer, imagery measuring the visible to shortwave infrared regions (VSWIR) of the spectrum have shown impressive capacity to map plant species and coarser land-cover associations, yet techniques have not been widely tested at regional and greater spatial scales. The Hyperspectral Infrared Imager (HyspIRI) mission is a VSWIR hyperspectral and thermal satellite being considered for development by NASA. The goal of this study was to assess multi-temporal, HyspIRI-like satellite imagery for improved land cover mapping relative to multispectral satellites. We mapped FAO Land Cover Classification System (LCCS) classes over 22,500 km2 in the San Francisco Bay Area, California using 30-m HyspIRI, Landsat 8 and Sentinel-2 imagery simulated from data acquired by NASA's AVIRIS airborne sensor. Random Forests (RF) and Multiple-Endmember Spectral Mixture Analysis (MESMA) classifiers were applied to the simulated images and accuracies were compared to those from real Landsat 8 images. The RF classifier was superior to MESMA, and multi-temporal data yielded higher accuracy than summer-only data. With RF, hyperspectral data had overall accuracy of 72.2% and 85.1% with full 20-class and reduced 12-class schemes, respectively. Multispectral imagery had lower accuracy. For example, simulated and real Landsat data had 7.5% and 4.6% lower accuracy than HyspIRI data with 12 classes, respectively. In summary, our results indicate increased mapping accuracy using HyspIRI multi-temporal imagery, particularly in discriminating different natural vegetation types, such as

  7. Evaluation of ERTS-1 data for acquiring land use data of northern Megalopolis. [New England

    NASA Technical Reports Server (NTRS)

    Simpson, R. B.; Lindgren, D. T.; Goldstein, W. D.

    1974-01-01

    State planners are increasingly becoming interested in ERTS as a possible method for acquiring land use data. An important consideration to them is whether ERTS can provide such data at a savings in both time and money over alternative systems. A preliminary evaluation of ERTS as a planning tool is given.

  8. Land-Use Change: Impacts of Climate Variations and Policies Examples From Northern Shaanxi Province, China

    NASA Astrophysics Data System (ADS)

    Ostwald, M.

    2003-12-01

    Phases of dynamical change are taking place in many developing countries causing land-use change. In China there has been enormous economic growth since 1978 followed by impacts on the environmental, social and economical conduct of the society. One of the counter actions taken by the Government to halt the environmental degradation in the Loess Plateau has been the introduction of the Crop Conversion Program in 1999, stopping agricultural activity in slope areas, mainly used by small-scale farmers. At the same time climate variations have also been evident in the area with decreases in rainfall and increases in temperature since 1970. The aim here is to examine what vegetation changes are seen on large scales in the area from 2000-2002, and how they correlate to local land-use changes. We then investigate how the land-use changes correlated with climate variations and/or policies and reforms. The data included in this integrated assessment includes remote sensing information from MODIS and ASTER images, climate and statistical data as well as farmer's participatory data. The results show that the large-scale vegetation has increased and that correlates well with dramatic local land-use change caused by the policy implementation. This however is not correlated with the climate variation found during this time (both lagged and simultaneous) which show a less favorable vegetation condition; all very well perceived by farmers. Hence the direct force behind the extreme land-use change is more associated with policy and economics than climate

  9. Correlation of Spatio-Temporal Contaminant Distribution, Land Use, and Hydrogeological Factors in the Karst Aquifers of Northern Puerto Rico

    NASA Astrophysics Data System (ADS)

    Torres Torres, N. I.; Padilla, I. Y.

    2015-12-01

    Karst aquifers are characterized by caves, springs, and sinkholes, and typified by interconnected fissures, fractures and conduits. These characteristics make these aquifers highly productive, and vulnerable to contamination. Previous studies in the northern karst aquifers of Puerto Rico have shown significant distribution of contaminants, including volatile organic compounds, phthalates and other contaminants of emerging concern, beyond demarked sources of contamination. This study develops spatial-temporal distributions of phthalate contaminants in the karst system of northern Puerto Rico and assesses statistical correlations between hydrogeologic factors and groundwater contamination with phthalates. Geographic Information Systems (GIS) tools and technologies, and statistical models are applied to attain these objectives. Results show that there is an extensive contamination with phthalates that varies with time. Contamination is present in the confined and shallow aquifers. Di-(2-ethylhexyl) phthalate (DEHP) is the most detected contaminant (20.6% of the sites). Diethyl phthalate and and dibutyl phthalate are also detected in 6.7% and 8.24% of the sites, respectively. Phthalates detected as mixtures components are significantly detected in areas of high urban and industrial development. They are also detected in areas within 5 miles of superfund sites and landfills. The results indicate that phthalate contamination is highly related to land use. Statistical models show that the hydraulic conductivity of the aquifers, sinkholes density, and time are significantly related to the presence of phthalates in groundwater. The extensive spatio-temporal contamination suggests that contaminants can persist in the environment for long periods of time, and that land use and hydrogeological factors are important factors contributing to the presence of emerging contaminants in karst systems.

  10. Effects of anthropogenic groundwater exploitation on land surface processes: A case study of the Haihe River Basin, northern China

    NASA Astrophysics Data System (ADS)

    Zou, Jing; Xie, Zhenghui; Zhan, Chesheng; Qin, Peihua; Sun, Qin; Jia, Binghao; Xia, Jun

    2015-05-01

    In this study, we incorporated a groundwater exploitation scheme into the land surface model CLM3.5 to investigate the effects of the anthropogenic exploitation of groundwater on land surface processes in a river basin. Simulations of the Haihe River Basin in northern China were conducted for the years 1965-2000 using the model. A control simulation without exploitation and three exploitation simulations with different water demands derived from socioeconomic data related to the Basin were conducted. The results showed that groundwater exploitation for human activities resulted in increased wetting and cooling effects at the land surface and reduced groundwater storage. A lowering of the groundwater table, increased upper soil moisture, reduced 2 m air temperature, and enhanced latent heat flux were detected by the end of the simulated period, and the changes at the land surface were related linearly to the water demands. To determine the possible responses of the land surface processes in extreme cases (i.e., in which the exploitation process either continued or ceased), additional hypothetical simulations for the coming 200 years with constant climate forcing were conducted, regardless of changes in climate. The simulations revealed that the local groundwater storage on the plains could not contend with high-intensity exploitation for long if the exploitation process continues at the current rate. Changes attributable to groundwater exploitation reached extreme values and then weakened within decades with the depletion of groundwater resources and the exploitation process will therefore cease. However, if exploitation is stopped completely to allow groundwater to recover, drying and warming effects, such as increased temperature, reduced soil moisture, and reduced total runoff, would occur in the Basin within the early decades of the simulation period. The effects of exploitation will then gradually disappear, and the variables will approach the natural state and

  11. Effects of anthropogenic groundwater exploitation on land surface processes: A case study of the Haihe River Basin, Northern China

    NASA Astrophysics Data System (ADS)

    Xie, Z.; Zou, J.; Qin, P.; Sun, Q.

    2014-12-01

    In this study, we incorporated a groundwater exploitation scheme into the land surface model CLM3.5 to investigate the effects of the anthropogenic exploitation of groundwater on land surface processes in a river basin. Simulations of the Haihe River Basin in northern China were conducted for the years 1965-2000 using the model. A control simulation without exploitation and three exploitation simulations with different water demands derived from socioeconomic data related to the Basin were conducted. The results showed that groundwater exploitation for human activities resulted in increased wetting and cooling effects at the land surface and reduced groundwater storage. A lowering of the groundwater table, increased upper soil moisture, reduced 2 m air temperature, and enhanced latent heat flux were detected by the end of the simulated period, and the changes at the land surface were related linearly to the water demands. To determine the possible responses of the land surface processes in extreme cases (i.e., in which the exploitation process either continued or ceased), additional hypothetical simulations for the coming 200 years with constant climate forcing were conducted, regardless of changes in climate. The simulations revealed that the local groundwater storage on the plains could not contend with high-intensity exploitation for long if the exploitation process continues at the current rate. Changes attributable to groundwater exploitation reached extreme values and then weakened within decades with the depletion of groundwater resources and the exploitation process will therefore cease. However, if exploitation is stopped completely to allow groundwater to recover, drying and warming effects, such as increased temperature, reduced soil moisture, and reduced total runoff, would occur in the Basin within the early decades of the simulation period. The effects of exploitation will then gradually disappear, and the land surface variables will approach the

  12. Distribution of Burkholderia pseudomallei in Northern Australia, a Land of Diversity

    PubMed Central

    McRobb, Evan; Kaestli, Mirjam; Price, Erin P.; Sarovich, Derek S.; Mayo, Mark; Warner, Jeffrey; Spratt, Brian G.

    2014-01-01

    Burkholderia pseudomallei is a Gram-negative soil bacillus that is the etiological agent of melioidosis and a biothreat agent. Little is known about the biogeography of this bacterium in Australia, despite its hyperendemicity in the northern region of this continent. The population structure of 953 Australian B. pseudomallei strains representing 779 and 174 isolates of clinical and environmental origins, respectively, was analyzed using multilocus sequence typing (MLST). Bayesian population structure and network SplitsTree analyses were performed on concatenated MLST loci, and sequence type (ST) diversity and evenness were examined using Simpson's and Pielou's indices and a multivariate dissimilarity matrix. Bayesian analysis found two B. pseudomallei populations in Australia that were geographically distinct; isolates from the Northern Territory were grouped mainly into the first population, whereas the majority of isolates from Queensland were grouped in a second population. Differences in ST evenness were observed between sampling areas, confirming that B. pseudomallei is widespread and established across northern Australia, with a large number of fragmented habitats. ST analysis showed that B. pseudomallei populations diversified as the sampling area increased. This observation was in contrast to smaller sampling areas where a few STs predominated, suggesting that B. pseudomallei populations are ecologically established and not frequently dispersed. Interestingly, there was no identifiable ST bias between clinical and environmental isolates, suggesting the potential for all culturable B. pseudomallei isolates to cause disease. Our findings have important implications for understanding the ecology of B. pseudomallei in Australia and for potential source attribution of this bacterium in the event of unexpected cases of melioidosis. PMID:24657869

  13. Distribution of Burkholderia pseudomallei in northern Australia, a land of diversity.

    PubMed

    McRobb, Evan; Kaestli, Mirjam; Price, Erin P; Sarovich, Derek S; Mayo, Mark; Warner, Jeffrey; Spratt, Brian G; Currie, Bart J

    2014-06-01

    Burkholderia pseudomallei is a Gram-negative soil bacillus that is the etiological agent of melioidosis and a biothreat agent. Little is known about the biogeography of this bacterium in Australia, despite its hyperendemicity in the northern region of this continent. The population structure of 953 Australian B. pseudomallei strains representing 779 and 174 isolates of clinical and environmental origins, respectively, was analyzed using multilocus sequence typing (MLST). Bayesian population structure and network SplitsTree analyses were performed on concatenated MLST loci, and sequence type (ST) diversity and evenness were examined using Simpson's and Pielou's indices and a multivariate dissimilarity matrix. Bayesian analysis found two B. pseudomallei populations in Australia that were geographically distinct; isolates from the Northern Territory were grouped mainly into the first population, whereas the majority of isolates from Queensland were grouped in a second population. Differences in ST evenness were observed between sampling areas, confirming that B. pseudomallei is widespread and established across northern Australia, with a large number of fragmented habitats. ST analysis showed that B. pseudomallei populations diversified as the sampling area increased. This observation was in contrast to smaller sampling areas where a few STs predominated, suggesting that B. pseudomallei populations are ecologically established and not frequently dispersed. Interestingly, there was no identifiable ST bias between clinical and environmental isolates, suggesting the potential for all culturable B. pseudomallei isolates to cause disease. Our findings have important implications for understanding the ecology of B. pseudomallei in Australia and for potential source attribution of this bacterium in the event of unexpected cases of melioidosis. PMID:24657869

  14. Impacts of snow and organic soils parameterization on northern Eurasian soil temperature profiles simulated by the ISBA land surface model

    NASA Astrophysics Data System (ADS)

    Decharme, Bertrand; Brun, Eric; Boone, Aaron; Delire, Christine; Le Moigne, Patrick; Morin, Samuel

    2016-04-01

    In this study we analyzed how an improved representation of snowpack processes and soil properties in the multilayer snow and soil schemes of the Interaction Soil-Biosphere-Atmosphere (ISBA) land surface model impacts the simulation of soil temperature profiles over northern Eurasian regions. For this purpose, we refine ISBA's snow layering algorithm and propose a parameterization of snow albedo and snow compaction/densification adapted from the detailed Crocus snowpack model. We also include a dependency on soil organic carbon content for ISBA's hydraulic and thermal soil properties. First, changes in the snowpack parameterization are evaluated against snow depth, snow water equivalent, surface albedo, and soil temperature at a 10 cm depth observed at the Col de Porte field site in the French Alps. Next, the new model version including all of the changes is used over northern Eurasia to evaluate the model's ability to simulate the snow depth, the soil temperature profile, and the permafrost characteristics. The results confirm that an adequate simulation of snow layering and snow compaction/densification significantly impacts the snowpack characteristics and the soil temperature profile during winter, while the impact of the more accurate snow albedo computation is dominant during the spring. In summer, the accounting for the effect of soil organic carbon on hydraulic and thermal soil properties improves the simulation of the soil temperature profile. Finally, the results confirm that this last process strongly influences the simulation of the permafrost active layer thickness and its spatial distribution.

  15. Mapping of land cover in northern California with simulated hyperspectral satellite imagery

    NASA Astrophysics Data System (ADS)

    Clark, Matthew L.; Kilham, Nina E.

    2016-09-01

    Land-cover maps are important science products needed for natural resource and ecosystem service management, biodiversity conservation planning, and assessing human-induced and natural drivers of land change. Analysis of hyperspectral, or imaging spectrometer, imagery has shown an impressive capacity to map a wide range of natural and anthropogenic land cover. Applications have been mostly with single-date imagery from relatively small spatial extents. Future hyperspectral satellites will provide imagery at greater spatial and temporal scales, and there is a need to assess techniques for mapping land cover with these data. Here we used simulated multi-temporal HyspIRI satellite imagery over a 30,000 km2 area in the San Francisco Bay Area, California to assess its capabilities for mapping classes defined by the international Land Cover Classification System (LCCS). We employed a mapping methodology and analysis framework that is applicable to regional and global scales. We used the Random Forests classifier with three sets of predictor variables (reflectance, MNF, hyperspectral metrics), two temporal resolutions (summer, spring-summer-fall), two sample scales (pixel, polygon) and two levels of classification complexity (12, 20 classes). Hyperspectral metrics provided a 16.4-21.8% and 3.1-6.7% increase in overall accuracy relative to MNF and reflectance bands, respectively, depending on pixel or polygon scales of analysis. Multi-temporal metrics improved overall accuracy by 0.9-3.1% over summer metrics, yet increases were only significant at the pixel scale of analysis. Overall accuracy at pixel scales was 72.2% (Kappa 0.70) with three seasons of metrics. Anthropogenic and homogenous natural vegetation classes had relatively high confidence and producer and user accuracies were over 70%; in comparison, woodland and forest classes had considerable confusion. We next focused on plant functional types with relatively pure spectra by removing open-canopy shrublands

  16. Can we reconcile atmospheric estimates of the Northern terrestrial carbon sink with land-based accounting?

    SciTech Connect

    Ciais, Philippe; Luyssaert, Sebastiaan; Chevallier, Fredric; Poussi, Zegbeu; Peylin, Philippe; Breon, Francois-Marie; Canadell, J.G.; Shvidenko, Anatoly; Jonas, Matthias; King, Anthony Wayne; Schulze, E.-D.; Roedenbeck, Christian; Piao, Shilong; Peters, Wouter

    2010-10-01

    We estimatethenorthernhemisphere(NH)terrestrialcarbon sink bycomparingfourrecentatmosphericinversionswith land-based Caccountingdataforsixlargenorthernregions. The meanNHterrestrialCO2 sink fromtheinversionmodelsis 1.7 PgCyear1 over theperiod2000 2004. Theuncertaintyof this estimateisbasedonthetypicalindividual(1-sigma) precision ofoneinversion(0.9PgCyear1) andisconsistent with themin max rangeofthefourinversionmeanestimates (0.8 PgCyear1). Inversionsagreewithintheiruncertaintyfor the distributionoftheNHsinkofCO2 in longitude,withRussia being thelargestsink.Theland-basedaccountingestimateof NH carbonsinkis1.7PgCyear1 for thesumofthesixregions studied. The1-sigmauncertaintyoftheland-basedestimate (0.3 PgCyear1) issmallerthanthatofatmosphericinversions, but noindependentland-basedfluxestimateisavailableto derive a betweenaccountingmodel uncertainty. Encouragingly, thetop-downatmosphericandthebottom-up land-based methodsconvergetoconsistentmeanestimates within theirrespectiveerrors,increasingtheconfidenceinthe overall budget.Theseresultsalsoconfirmthecontinuedcritical role ofNHterrestrialecosystemsinslowingdownthe atmospheric accumulationofanthropogenicCO2

  17. On the influence of land cover on early Holocene climate in northern latitudes

    NASA Astrophysics Data System (ADS)

    Rivers, Aaron R.; Lynch, Amanda H.

    2004-11-01

    This study presents a factorial experimental strategy for assessing the effects of the changing land surface on early Holocene (˜11 ka) climate in Beringia. The strategy uses a coupled land-atmosphere single column model in a series of perturbation experiments that vary the vegetation type, lake cover, and soil specification simultaneously. Two sites and eight years of model forcing are chosen to determine the importance of differing terrestrial histories, local climate, and interannual variability. Eastern Beringia is represented by Fairbanks, Alaska, and western Beringia is represented by Elikchan Lake, Siberia. Evaluations of model response are performed using metrics important for vegetation growth, such as growing degree days and moisture availability. For both sites, large-scale interannual variability has a greater impact on the local climate than changes in the land surface specification for temperature-based responses, but not for moisture availability. Of the three land surface parameters tested, vegetation type is most influential. Vegetation transitions from tundra to boreal forest leads to increased precipitation, winter snow depth, and low cloud, leading to a delayed snowmelt in forested regions. This is in contrast to expectations based on albedo arguments alone. In western Beringia, a positive feedback is suggested in warming due to the presence of boreal forest, consistent with some observations that Siberian deciduous forest persisted longer than Alaskan deciduous forest in the context of large-scale cooling of the climate. The reverse was found to be true in eastern Beringia, where deciduous forests exhibited a cooling effect due to increases in albedo. The response to soil variations was relatively small, but the inclusion of inland lakes tends in general to cool the surface, although in some years a warming is evident due to the surface energy balance shifting in favor of downwelling longwave heating over evaporative cooling.

  18. Land cover dynamics following a deforestation ban in northern Costa Rica

    NASA Astrophysics Data System (ADS)

    Fagan, M. E.; DeFries, R. S.; Sesnie, S. E.; Arroyo, J. P.; Walker, W.; Soto, C.; Chazdon, R. L.; Sanchun, A.

    2013-09-01

    Forest protection policies potentially reduce deforestation and re-direct agricultural expansion to already-cleared areas. Using satellite imagery, we assessed whether deforestation for conversion to pasture and cropland decreased in the lowlands of northern Costa Rica following the 1996 ban on forest clearing, despite a tripling of area under pineapple cultivation in the last decade. We observed that following the ban, mature forest loss decreased from 2.2% to 1.2% per year, and the proportion of pineapple and other export-oriented cropland derived from mature forest declined from 16.4% to 1.9%. The post-ban expansion of pineapples and other crops largely replaced pasture, exotic and native tree plantations, and secondary forests. Overall, there was a small net gain in forest cover due to a shifting mosaic of regrowth and clearing in pastures, but cropland expansion decreased reforestation rates. We conclude that forest protection efforts in northern Costa Rica have likely slowed mature forest loss and succeeded in re-directing expansion of cropland to areas outside mature forest. Our results suggest that deforestation bans may protect mature forests better than older forest regrowth and may restrict clearing for large-scale crops more effectively than clearing for pasture.

  19. Aeolian desertification from the mid-1970s to 2005 in Otindag Sandy Land, Northern China

    NASA Astrophysics Data System (ADS)

    Liu, Shulin; Wang, Tao

    2007-01-01

    Aeolian desertification in Otindag Sandy Land has expanded dramatically during the past 50 years. This research explored processes and causes of aeolian desertification in the study area. The results showed that aeolian desertification development in Zhenglan Qi of typical region located at the center in the study area can be divided into three stages including rapid occurrence before 1987, parts of rehabilitation and most of deterioration from 1987 to 2000 and little rapid rehabilitation occurrence from 2000 to 2005, according to remote sensing images and field investigations. Gradually declining MI indicated that climate change was not the major cause of aeolian desertification development during the last 40 years, while increasing population should be the underlying cause of local aeolian desertification. Irrational human activities mainly including unsuitable reclamation in the 1960s and lasting over-grazing after 1980 are direct causes contributing to local aeolian desertification, especially over-grazing, while climate change often played a revealer of irrational human activities mainly through drought events. Over-grazing and undesirable climate have different functions during the whole aeolian desertification process. Over-grazing gradually changed grasslands to slight aeolian desertified lands at the initial stage, while climate with windy days or droughts often accelerated formation of serious aeolian desertified lands. Aeolian desertification in the study area both possesses occurrence possibility and great rehabilitative potential. At present, more integrated countermeasures combating local aeolian desertification still are expected.

  20. The structure and diversity of freshwater diatom assemblages from Franz Josef Land Archipelago: a northern outpost for freshwater diatoms

    PubMed Central

    Hamilton, Paul B.; Ballesteros, Enric; Gavrilo, Maria; Friedlander, Alan M.; Sala, Enric

    2016-01-01

    We examined diatom assemblages from 18 stream and pond samples in the Franz Josef Land Archipelago (FJL), the most northern land of Eurasia. More than 216 taxa were observed, revealing a rich circumpolar diatom flora, including many undescribed taxa. Widely distributed taxa were the most abundant by cell densities, while circumpolar taxa were the most species rich. Stream and pond habitats hosted different assemblages, and varied along a pH gradient. Diatoma tenuis was the most abundant and ubiquitous taxon. However, several circumpolar taxa such as Chamaepinnularia gandrupii, Cymbella botellus, Psammothidium sp. and Humidophila laevissima were also found in relatively high abundances. Aerophilic taxa were an important component of FJL diatom assemblages (Humidophila spp., Caloneis spp. and Pinnularia spp.), reflecting the large and extreme seasonal changes in Arctic conditions. We predict a decrease in the abundance of circumpolar taxa, an increase in local (α-) freshwater diatom diversity, but a decrease in regional diversity (circumpolar homogenization) as a result of current warming trends and to a lesser extent the increasing human footprint in the region. PMID:26925329

  1. The structure and diversity of freshwater diatom assemblages from Franz Josef Land Archipelago: a northern outpost for freshwater diatoms.

    PubMed

    Pla-Rabés, Sergi; Hamilton, Paul B; Ballesteros, Enric; Gavrilo, Maria; Friedlander, Alan M; Sala, Enric

    2016-01-01

    We examined diatom assemblages from 18 stream and pond samples in the Franz Josef Land Archipelago (FJL), the most northern land of Eurasia. More than 216 taxa were observed, revealing a rich circumpolar diatom flora, including many undescribed taxa. Widely distributed taxa were the most abundant by cell densities, while circumpolar taxa were the most species rich. Stream and pond habitats hosted different assemblages, and varied along a pH gradient. Diatoma tenuis was the most abundant and ubiquitous taxon. However, several circumpolar taxa such as Chamaepinnularia gandrupii, Cymbella botellus, Psammothidium sp. and Humidophila laevissima were also found in relatively high abundances. Aerophilic taxa were an important component of FJL diatom assemblages (Humidophila spp., Caloneis spp. and Pinnularia spp.), reflecting the large and extreme seasonal changes in Arctic conditions. We predict a decrease in the abundance of circumpolar taxa, an increase in local (α-) freshwater diatom diversity, but a decrease in regional diversity (circumpolar homogenization) as a result of current warming trends and to a lesser extent the increasing human footprint in the region. PMID:26925329

  2. Satellite observations of changes in snow-covered land surface albedo during spring in the Northern Hemisphere

    NASA Astrophysics Data System (ADS)

    Atlaskina, K.; Berninger, F.; de Leeuw, G.

    2015-09-01

    Thirteen years of Moderate Resolution Imaging Spectroradiometer (MODIS) surface albedo data for the Northern Hemisphere during the spring months (March-May) were analyzed to determine temporal and spatial changes over snow-covered land surfaces. Tendencies in land surface albedo change north of 50° N were analyzed using data on snow cover fraction, air temperature, vegetation index and precipitation. To this end, the study domain was divided into six smaller areas, based on their geographical position and climate similarity. Strong differences were observed between these areas. As expected, snow cover fraction (SCF) has a strong influence on the albedo in the study area and can explain 56 % of variation of albedo in March, 76 % in April and 92 % in May. Therefore the effects of other parameters were investigated only for areas with 100 % SCF. The second largest driver for snow-covered land surface albedo changes is the air temperature when it exceeds a value between -15 and -10 °C, depending on the region. At monthly mean air temperatures below this value no albedo changes are observed. The Enhanced Vegetation Index (EVI) and precipitation amount and frequency were independently examined as possible candidates to explain observed changes in albedo for areas with 100 % SCF. Amount and frequency of precipitation were identified to influence the albedo over some areas in Eurasia and North America, but no clear effects were observed in other areas. EVI is positively correlated with albedo in Chukotka Peninsula and negatively in eastern Siberia. For other regions the spatial variability of the correlation fields is too high to reach any conclusions.

  3. Modeling land subsidence due to shallow-water hydrocarbon production: A case study in the northern Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Gambolati, G.; Castelletto, N.; Ferronato, M.; Janna, C.; Teatini, P.

    2012-12-01

    One major environmental concern of subsurface fluid withdrawal is land subsidence. The issue of a reliable estimate and prediction of the expected anthropogenic land subsidence is particularly important whenever the production of hydrocarbon (oil and gas) occurs from large reservoirs located close to deltaic zones (e.g., Mississippi, Po, Nile, Niger, Yellow rivers) or shallow-water with low-lying coastlands (e.g., Northern Caspian sea, Dutch Wadden Sea). In such cases even a small reduction of the ground elevation relative to the mean sea level may impact seriously on human settlements and natural environment. The monitoring of the ongoing land subsidence has been significantly improved over the last decade by SAR-based interferometry. These measurements can be quite effectively used to map the process and calibrate geomechanical models for predicting the future event. However, this powerful methodology cannot be implemented off-shore. Although permanent GPS stations can be established to monitor the movement of the production facilities usually installed above the gravity center of a reservoir, an accurate characterization of the settlement bowl affecting the sea bottom, with a possible migration toward the shore, is a challenge still today. In the present communication the case study of the Riccione gas reservoir is discussed. The field is located in the near-shore northern Adriatic Sea, approximately 15 km far from the coastline, where the seawater height is about 20 m. The gas-bearing strata are 1100 m deep and are hydraulically connected to a relatively weak aquifer. Production of 70% of the cumulative reserves as of 2006 yielded a pore pressure decrease of 60 bars. Reliable geometry and geomechanical properties of the depleted formations were detected with the aid of a 3D seismic survey and a borehole equipped with radioactive markers, respectively. The latter pointed out that the Riccione formations are characterized by an unusually high oedometer

  4. Land-level changes from a late Holocene earthquake in the northern Puget Lowland, Washington

    NASA Astrophysics Data System (ADS)

    Kelsey, Harvey M.; Sherrod, Brian; Johnson, Samuel Y.; Dadisman, Shawn V.

    2004-06-01

    An earthquake, probably generated on the southern Whidbey Island fault zone, caused 1 2 m of ground-surface uplift on central Whidbey Island ˜2800 3200 yr ago. The cause of the uplift is a fold that grew coseismically above a blind fault that was the earthquake source. Both the fault and the fold at the fault's tip are imaged on multichannel seismic refection profiles in Puget Sound immediately east of the central Whidbey Island site. Uplift is documented through contrasting histories of relative sea level at two coastal marshes on either side of the fault. Late Holocene shallow-crustal earthquakes of Mw = 6.5 7 pose substantial seismic hazard to the northern Puget Lowland.

  5. Magnetic anomalies northeast of Cape Adare, northern Victoria Land (Antarctica), and their relation to onshore structures

    USGS Publications Warehouse

    Damaske, D.; Läufer, A.L.; Goldmann, F.; Möller, H.-D.; Lisker, F.

    2007-01-01

    An aeromagnetic survey was flown over the offshore region northeast of Cape Adare and the magnetic anomalies compared to onshore structures between Pennell Coast and Tucker Glacier. The magnetic anomalies show two nearly orthogonal major trends. NNW-SSE trending anomalies northeast of Cape Adare represent seafloor spreading within the Adare Trough. A connection of these anomalies to the Northern Basin of the Ross Sea is not clear. Onshore faults are closely aligned to offshore anomalies. Main trends are NW-SE to NNW-SSE and NE-SW to NNESSW. NNW-SSE oriented dextral-transtensional to extensional faults parallel the Adare Peninsula and Adare Trough anomalies. NE-SW trending normal faults appear to segment the main Hallett volcanic bodies.

  6. Federally owned coal and Federal lands in the Northern and Central Appalachian Basin coal regions

    USGS Publications Warehouse

    Tewalt, S.J.

    2002-01-01

    The U.S. Geological Survey (USGS) assessed five coal beds or coal zones in the northern and central Appalachian Basin coal regions for the National Coal Resource Assessment: the Pittsburgh coal bed, the Upper Freeport coal bed, the Fire Clay coal zone, the Pond Creek coal zone, and the Pocahontas No. 3 coal bed. The assessment produced stratigraphic and geochemical databases and digital coal maps, or models, which characterized the coal beds and coal zones. Using the assessment models, the USGS estimated original and remaining (unmined) resources for these coal beds or zones. The Appalachian Basin assessment was conducted in collaboration with the State geological surveys of West Virginia, Pennsylvania, Ohio, Maryland, Kentucky, and Virginia.

  7. Federally owned coal and Federal lands in the northern and central Appalachian Basin coal regions

    SciTech Connect

    Susan J. Tewalt

    2002-02-01

    The US Geological Survey (USGS) assessed five coals beds or coal zones in the northern and central Appalachian Basin coal regions for the National Coal Resource Assessment: the Pittsburgh coal bed, the Upper Freeport coal bed, the Fire Clay coal zone, the Pond Creek coal zone, and the Pocahontas No. 3 coal bed. The assessment produced stratigraphic and geochemical databases and digital coal maps, or models, which characterized the coal beds and coal zones. Using the assessment models, the USGS estimated original and remaining (unmined) resources for these coal beds or zones. The Appalachian Basin assessment was conducted in collaboration with the State geological surveys of West Virginia, Pennsylvania, Ohio, Maryland, Kentucky, and Virginia. 3 refs., 7 figs.

  8. The interactions of fire regimes, land management, vegetation dynamics and the atmosphere in northern Australian savannas

    NASA Astrophysics Data System (ADS)

    Cook, Garry; Meyer, Mick

    2014-05-01

    The Australian tropical savannas burn with frequencies ranging from one in five to one in two years. Uniquely for an OECD country, these fires contribute substantially to accountable national greenhouse gas emissions. Concern about those emissions has led to the development of approaches to imprive fire management to reduce emissions and increase carbon sequestration. Savanna dyanmics are however, also determined by interactions with rainfall regimes. In this paper, we present an overview of fire regimes in northern Australia, their effects on the greenhouse gas emissions and how management of those fires interacts with climatic variability and likely climate change. Data will be presented from on-ground measurements of emissions, vegetation dyanamics as well as interpretation of satellite imagery of fire scars.

  9. Late-glacial to Holocene transition in northern Spain deduced from land-snail shelly accumulations

    NASA Astrophysics Data System (ADS)

    Yanes, Yurena; Gutiérrez-Zugasti, Igor; Delgado, Antonio

    2012-09-01

    Shells of the helicid Cepaea nemoralis were studied using taphonomic, isotopic and morphometric measurements to estimate late glacial-Holocene (~ 12.1-6.3 cal ka BP) environmental conditions in northern Spain. Higher taphonomic alteration among Holocene shells suggests lower sedimentation rates or higher shell-destruction rates than during glacial conditions. Shells preserved the aragonitic composition despite differing degree of skeleton damage. Shell δ13C values were - 10.3 ± 1.1‰, - 8.2 ± 2.3‰, and - 7.3 ± 1.6‰ for modern, Holocene and late-glacial individuals, respectively. Higher δ13C values during the late-glacial and some Holocene periods imply higher water stress of C3 plants and/or higher limestone contribution than today. Intrashell δ13C values were higher during juvenile stages suggesting higher limestone ingestion to promote shell growth. Shell δ18O values were - 1.1 ± 0.7‰, - 0.9 ± 0.8‰ and - 0.1 ± 0.7‰ for modern, Holocene and late-glacial specimens, respectively. A snail flux-balance model suggests that during ~ 12.1 - 10.9 cal ka BP conditions were drier and became wetter at ~ 8.4 - 6.3 cal ka BP and today. Intrashell δ18O profiles reveal that glacial individuals experienced more extreme seasonality than interglacial shells, despite possible larger hibernation periods. Shell size correlated positively with δ18O values, suggesting that growth rates and ultimate adult size of C. nemoralis may respond to climate fluctuation in northern Spain.

  10. Investigation of land use of northern megalopolis using ERTS-1 imagery. [Connecticut, Massachusetts, and Rhode Island

    NASA Technical Reports Server (NTRS)

    Simpson, R. B. (Principal Investigator); Lindgren, D. T.; Goldstein, W.

    1974-01-01

    The author has identified the following significant results. It was concluded that ERTS land use mapping, in spite of portraying megalopolis more accurately and dramatically than the best past efforts, is in danger of falling into the category of being too revolutionary for many planners and too conventional for many electronics engineers. Two alternative solutions are implied: one is to improve the ERTS product to the level where it will be completely accepted by planners, and the other is to increase support for the present somewhat primitive product through education, cost-sharing, and legislation.

  11. A land cover change study in the Highlands of Northern Ethiopia using a flight of aerial photographs dating back to the 1930s

    NASA Astrophysics Data System (ADS)

    Guyassa, Etefa; Frankl, Amaury; Zenebe, Amanuel; Lanckriet, Sil; Demissie, Biadgilgn; Zenebe, Gebreyohanis; Poesen, Jean; Nyssen, Jan

    2016-04-01

    In the Highlands of Northern Ethiopia, land degradation is claimed to have occurred over a long time mainly due agricultural practices and lack of land management. However, quantitative information on the long term land use, cover and management change is rare. The knowledge of such historical changes is essential for the present and future land management for sustainable development, especially in an agriculture-based economy. Hence, this study aimed to investigate the changes of land use, cover and management around Hagere Selam, Northern Ethiopia, over the last 80 years (1935 - 2014). We recovered a flight of ten aerial photographs at an approximate scale of 1:11,500, realized by the Italian Military Geographical Institute in 1935, along a mountain ridge between 13.6490°N, 39.1848°E and 13.6785°N, 39.2658°E. Jointly with Google Earth images (2014), the historical aerial photographs were used to compare changes over the long time. The point-count technique was used by overlaying a grid of 18 x 15 points (small squares) on 20 cm x 15 cm aerial photographs and on Google Earth images representing the same area. Occurrence of major land cover types (cropland, forest, grassland, shrubland, bare land, built-up areas and water body) was counted to compute their proportion in 1935 and 2014. In 1935, cropland, shrubland and built-up areas were predominant while other land cover types were not observed. On the Google Earth images, all categories were observed except forest. The results show that in both times cropland was the dominant land cover followed by shrubland. The proportion of cropland at present (70.5%) is approximately the same as in the 1930s (72%), but shrubland decreased and bare land, grassland and built-up areas have increased. Hence, the large share of cropland was maintained over the past long period without allowing for woody vegetation to expand its area, while some cropland was abandoned and converted to grassland and bare land. The increased

  12. Paleomagnetic study of the northern Ford Ranges, western Marie Byrd Land, West Antarctica: Motion between West and East Antarctica

    NASA Astrophysics Data System (ADS)

    Luyendyk, Bruce; Cisowski, Stan; Smith, Christine; Richard, Steve; Kimbrough, David

    1996-02-01

    A paleomagnetic study of Paleozoic and Mesozoic crystalline rocks in the northern Ford Ranges of Marie Byrd Land, West Antarctica, has determined a middle Cretaceous (circa 100 Ma) paleomagnetic pole and provided constraints on possible clockwise rotation of these ranges and on the rifting of east Gondwana. The 40Ar/39Ar thermochronology data from the Fosdick Mountains record a period of rapid cooling from ˜700°C beginning at ˜100 Ma. We relate this to extension, intrusion, and uplift associated with the beginning of rifting between Campbell Plateau and Marie Byrd Land. All rocks from the Fosdick and Chester Mountains are normally polarized. We interpret thermochronology and paleomagnetic data to infer that the region was extensively remagnetized in middle Cretaceous time. Inclinations in samples from the Chester Mountains are less steep than those from the Fosdick Mountains, which we interpret as ˜25° of south tilting of the Chesters. We interpret cooling age data for the time of magnetization to infer that the tilting began after 105 Ma and ended prior to 103 Ma. We further interpret this as constraining the beginning of extension between the Campbell Plateau and western Marie Byrd Land to the interval 105 to 103 Ma. Virtual geomagnetic poles from samples of Early Carboniferous age granodiorite from the western Phillips Mountains lie on the late Paleozoic apparent polar wander path for Australia transferred to Antarctica. Directions from 29 sites in the central and eastern Phillips and Fosdick Mountains give a Middle Cretaceous paleomagnetic pole at 222.3° E, 70.5° S (A95 6.1°, KAPPA 20.0). This pole is indistinguishable from other Middle Cretaceous poles for studies further east in Marie Byrd Land. Combining middle Cretaceous poles determined for three other studies of the Antarctic Peninsula, Thurston Island, and the Ruppert-Hobbs coasts with ours gives a Pacific West Antarctic pole at 215.2° E, 73.5° S (A95 4.0°, KAPPA 528.9). This pole is

  13. Full-Circle Color Panorama of Phoenix Landing Site on Northern Mars, Vertical Projection

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This view combines more than 400 images taken during the first several weeks after NASA's Phoenix Mars Lander arrived on an arctic plain at 68.22 degrees north latitude, 234.25 degrees east longitude on Mars.

    The full-circle panorama in approximately true color shows the polygonal patterning of ground in the landing area, similar to patterns in permafrost areas on Earth. North is toward the top. Trenches where Phoenix's robotic arm has been exposing subsurface material are visible just north of the lander.

    This view comprises more than 100 different camera pointings, with images taken through three different filters at each pointing. It is presented here as a vertical projection.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  14. Mediterranean valleys revisited: Linking soil erosion, land use and climate variability in the Northern Levant

    NASA Astrophysics Data System (ADS)

    Casana, Jesse

    2008-10-01

    This paper presents results of geomorphological and archaeological investigations undertaken in several small drainage basins in the Jebel al-Aqra region of southern Turkey. By focusing intensive archaeological settlement survey in basins where securely dated sequences of sedimentary valley fills have been recorded, spatially and temporally linked, high-resolution records of land use and soil erosion have been generated. Sedimentary data show that throughout most of the Holocene, floodplains remained rather stable, allowing deep soils to form. But in the past two millennia, probably from AD 150-700, a phase of severe soil erosion was initiated and resulted in the deposition of 3.5-5.0 m of alluvial sediments on valley floors. Archaeological and historical evidence suggest that while these areas were occupied by agrarian communities since at least 2800 BC, nearly three millennia of cultivation during the Bronze and Iron Ages had relatively little effect on soil erosion. The intensification of settlement throughout the region and the conversion of upland areas to intensive agricultural production during the Hellenistic, Roman and late Roman periods (300 BC-AD 650), however, created the necessary preconditions for severe soil erosion to occur. These data are compared against modern and paleoclimate studies of the eastern Mediterranean, which show an extremely variable precipitation regime and the effects that it can have on erosion. A 400-year lag between the initial settlement of upland areas and the first evidence of soil erosion suggest that it may have been the intersection of extreme precipitation events with particular land use conditions of the Roman and late Roman periods which worked together to drive soil erosion.

  15. Paleomagnetic study of the northern Ford Ranges, western Marie Byrd Land, West Antarctica: Motion between West and East Antarctica

    USGS Publications Warehouse

    Luyendyk, B.; Cisowski, S.; Smith, C.; Richard, S.; Kimbrough, D.

    1996-01-01

    A paleomagnetic study of Paleozoic and Mesozoic crystalline rocks in the northern Ford Ranges of Marie Byrd Land, West Antarctica, has determined a middle Cretaceous (circa 100 Ma) paleomagnetic pole and provided constraints on possible clockwise rotation of these ranges and on the rifting of east Gondwana. The 40Ar/39Ar thermochronology data from the Fosdick Mountains record a period of rapid cooling from ???700??C beginning at ???100 Ma. We relate this to extension, intrusion, and uplift associated with the beginning of rifting between Campbell Plateau and Marie Byrd Land. All rocks from the Fosdick and Chester Mountains are normally polarized. We interpret thermochronology and paleomagnetic data to infer that the region was extensively remagnetized in middle Cretaceous time. Inclinations in samples from the Chester Mountains are less steep than those from the Fosdick Mountains, which we interpret as ???25?? of south tilting of the Chesters. We interpret cooling age data for the time of magnetization to infer that the tilting began after 105 Ma and ended prior to 103 Ma. We further interpret this as constraining the beginning of extension between the Campbell Plateau and western Marie Byrd Land to the interval 105 to 103 Ma. Virtual geomagnetic poles from samples of Early Carboniferous age granodiorite from the western Phillips Mountains lie on the late Paleozoic apparent polar wander path for Australia transferred to Antarctica. Directions from 29 sites in the central and eastern Phillips and Fosdick Mountains give a Middle Cretaceous paleomagnetic pole at 222.3?? E, 70.5?? S (A95 6.1??, KAPPA 20.0). This pole is indistinguishable from other Middle Cretaceous poles for studies further east in Marie Byrd Land. Combining middle Cretaceous poles determined for three other studies of the Antarctic Peninsula. Thurston Island, and the Ruppert-Hobbs coasts with ours gives a Pacific West Antarctic pole at 215.2?? E, 73.5?? S (A95 4.0??, KAPPA 528.9). This pole is

  16. Assessment of model estimates of land-atmosphere CO2 exchange across Northern Eurasia

    SciTech Connect

    Rawlins, M. A.; McGuire, A. D.; Kimball, J. S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; Peng, S.; Rinke, A.; Saito, K.; Zhang, W.; Alkama, R.; Bohn, T. J.; Ciais, P.; Decharme, B.; Gouttevin, I.; Hajima, T.; Ji, D.; Krinner, G.; Lettenmaier, D. P.; Miller, P.; Moore, J. C.; Smith, B.; Sueyoshi, T.

    2015-07-28

    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960–2009 at 0.5° resolution, which is a scale common among many global carbon and climate model simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m⁻² yr⁻², equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960–1969 vs. 2000–2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our

  17. Magnetic petrology of ultramafic rocks and metabasites along the Lanterman-Mariner suture (Northern Victoria Land, Antarctica)

    NASA Astrophysics Data System (ADS)

    Strada, Eleonora; Lurcock, Pontus Conrad; Palmeri, Rosaria; Florindo, Fabio; Talarico, Franco Maria

    2016-04-01

    This study focuses on the integration between rock magnetism and metamorphic petrology of ultramafic rocks and metabasites, variably metamorphosed under UHP, eclogite or HP amphibolite facies peak conditions, and cropping out along the Lanterman-Mariner suture (Northern Victoria Land, Antarctica) in three different areas: the Lanterman Range, the Salamander Range and the Dessent Ridge. The outcrops along the Lanterman-Mariner suture provide a unique opportunity to define the relationships between magnetic properties and metamorphic evolution, in a wide P-T range, of ultramafic rocks and metabasites in the paleo-Pacific margin of Gondwana, an area which is well-studied from a petrological and structural point of view but lacking a rock magnetic study. To characterize the magnetic properties of these rocks, we performed a set of rock magnetic analyses (low-field magnetic susceptibility, natural remanence, thermomagnetic curves and hysteresis loops). We then characterized the minero-petrographical and compositional features of opaque minerals on selected samples using both the optical microscope and the Scanning Electron Microscope (SEM). The samples display a remarkable heterogeneity in the studied magnetic properties depending on both type and abundance of the carriers of magnetization (Fe-Ti oxides and sulphides). Independently of the degree of retrogression and lithology (eclogites, retrogressed eclogites, pirossenites and amphibolites), several samples contain variable amounts of both magnetite and pyrrhotite, while others show only magnetite as the main ferromagnetic mineral. The remaining samples mainly consist of paramagnetic minerals and may display small amounts of magnetite. Based on the microstructural evidence, more than one generation of ferromagnetic minerals may occur in retrogressed UHP ultramafic rocks and eclogites. These new data and interpretations are essential 1) to characterize and to verify primary and secondary oxide and sulphide

  18. Modelling nitrogen leaching from sewage sludge application to arable land in the Lombardy region (northern Italy).

    PubMed

    Fumagalli, Mattia; Perego, Alessia; Acutis, Marco

    2013-09-01

    Sewage sludge can be used as fertiliser, offering the possibility of safely recycling this waste product as a resource in agricultural applications. As the environmental concerns related to waste recycling in agricultural applications are well-known, restrictions on the use of sewage sludge have been implemented by the EU and local authorities. This work aimed to evaluate the nitrogen leaching associated with the application of sludge and the effectiveness of the temporal restrictions on its application implemented to safeguard the environment in the Lombardy region of northern Italy (120 days in Nitrate Vulnerable Zones and 90 days elsewhere) using the CropSyst model which was first validated. The effects of fertilisation using four different sludge types on N leaching were simulated at five sites under cultivation with maize and rice crops; six different timing schemes for sludge application were tested, three of which involved dates that were in agreement (AT) with the regulation, while the other three were not in agreement (NAT). We detected a significant effect of the sludge type and application timing, whereas the effect of their interaction was never significant. The mean annual leaching was 22 to 154 kg N ha(-1). The higher the ammonium N content in the sludge was, the greater the potential for N leaching was found to be. For the maize crop, the distribution of sludge in the late fall period resulted in significantly greater N leaching (61 kg N ha(-1)) and led to lower yields (9 t DM ha(-1)) compared to late winter fertilisation (49 kg N ha(-1); 10 t DM ha(-1)), whereas no differences in N leaching or yield were detected between AT and NAT, which was also observed for the rice crop. Therefore, the applied temporal constraints did not always appear to be advantageous for protecting the environment from leaching. PMID:23751334

  19. Soil organic carbon dynamics under long-term fertilizations in arable land of northern China

    NASA Astrophysics Data System (ADS)

    Zhang, W. J.; Wang, X. J.; Xu, M. G.; Huang, S. M.; Liu, H.; Peng, C.

    2010-02-01

    Soil carbon sequestration is a complex process influenced by agricultural practices, climate and soil conditions. This paper reports a study of long-term fertilization impacts on soil organic carbon (SOC) dynamic from six long-term experiments. The experiment sites are located from warm-temperate zone with a double-cropping system of corn (Zea mays L.) - wheat (Triticum Aestivium L.) rotation, to mild-temperate zones with mono-cropping systems of continuous corn, or a three-year rotation of corn-wheat-wheat. Mineral fertilizer applications result in an increasing trend in SOC except in the arid and semi-arid areas with the mono-cropping systems. Additional manure application is important to maintain SOC level in the arid and semi-arid areas. Carbon conversion rate is significant lower in the warm-temperate zone with double cropping system (6.8%-7.7%) than that in the mild-temperate areas with mono-cropping systems (15.8%-31.0%). The conversion rate is significantly correlated with annual precipitation and active accumulative temperature, i.e., higher conversion rate under lower precipitation and/or temperature conditions. Moreover, soil high in clay content has higher conversion rate than soils low in clay content. Soil carbon sequestration rate ranges from 0.07 to 1.461 t ha-1 year-1 in the upland of northern China. There is significantly linear correlation between soil carbon sequestration and carbon input at most sites, indicating that these soils are not carbon-saturated thus have potential to migrate more CO2 from atmosphere.

  20. Size distributions of mineral aerosols and dust emission flux observed over Horqin Sandy Land area in northern China

    NASA Astrophysics Data System (ADS)

    Li, X.; Zhang, H. S.

    2013-01-01

    Size distribution of mineral aerosols is of primary importance in determining their residence time in atmosphere, transport patterns, removal mechanisms as well as their effects on climate and human health. This study aims to obtain dust particle size distribution and size-resolved dust emission flux under different weather conditions over a sandy land area in northern China (Horqin Sandy Land, Inner Mongolia), using the observational data from Horqin sandstorm monitoring station in the spring of 2010 and 2012. Dust (PM20) mass concentration was measured by a 10-stage quartz crystal microbalance (QCM) cascade impactor. The statistical results indicate that finer dust particles (r ≤ 1.0 μm) take a large proportion of all PM20 concentration under clear-day conditions, while coarser dust particles (r ≥ 2.5 μm) concentration increased under dust-day conditions, with the peak occurring between 4-7 μm. The dust particle size distributions during the pre-dust-emission and dust-emission periods of a dust event on 7 April 2012 have similar features to the statistical results. During the dust event, the magnitude of dust emission flux of all sizes increased about one or two orders (0.1-10 μg m-2 s-1) as u* increase from 0.54 to 1.29 m s-1. The maximum total F value was about 43.0 μg m-2 s-1 and the maximum size-resolved F(Ddi) is 12.3 μg m-2 s-1 in 0.3-0.45 μm size bin when u* is 1.29 m s-1. Dust advection has effects on airborne dust size distribution, making the proportion of dust particles of different sizes more uniform, as observed in a non-local dust event on 19 April 2012.

  1. A new Eemian record of Antarctic tephra layers retrieved from the Talos Dome ice core (Northern Victoria Land)

    NASA Astrophysics Data System (ADS)

    Narcisi, Biancamaria; Petit, Jean Robert; Langone, Antonio; Stenni, Barbara

    2016-02-01

    Polar ice sheets are remarkable repositories of tephra layers. The Talos Dome ice core (72°49‧S, 159°11‧E), drilled at the edge of the East Antarctic Plateau, close to Late Quaternary volcanoes, offers considerable potential to extend the current tephra time-stratigraphic framework. A tephrochronological study was undertaken of the ice core sections related to the Last Interglacial and the transition to the subsequent glacial period. Thirteen macroscopically visible layers, interpreted to be related to primary deposition of fallout tephra, have been analysed for quantitative grain size and glass shard geochemistry. The layers, precisely framed within the climate (δ18O) record for the core, span in age from 111.6 ± 1.9 to 123.3 ± 2.2 ka. Coarse particle size suggests origin from regional sources. Indeed, the vast majority of the samples display an alkaline affinity and trachytic composition that are both typical geochemical features of rifting Antarctic volcanism. Using subtle differences in the geochemical signatures and the comparison with data from previous studies, a few layers are attributed to known coeval Mt. Melbourne eruptions. Another sample subset is consistent with derivation from The Pleiades and Mt. Rittmann volcanoes. One peculiar trachytic glass population appears to be related to activity of the more distant Marie Byrd Land volcanoes. The newly detected tephras provide stratigraphic markers that could facilitate future synchronisation and dating of palaeoclimatic records. The Talos Dome tephra inventory also contributes significantly to the reconstruction of the Northern Victoria Land explosive volcanism, for which chronostratigraphic data for the Last Interglacial temporal segment are poor.

  2. Full-Circle Color Panorama of Phoenix Landing Site on Northern Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation

    This view combines more than 400 images taken during the first several weeks after NASA's Phoenix Mars Lander arrived on an arctic plain at 68.22 degrees north latitude, 234.25 degrees east longitude on Mars.

    The full-circle panorama in approximately true color shows the polygonal patterning of ground at the landing area, similar to patterns in permafrost areas on Earth. The center of the image is the westward part of the scene. Trenches where Phoenix's robotic arm has been exposing subsurface material are visible in the right half of the image. The spacecraft's meteorology mast, topped by the telltale wind gauge, extends into the sky portion of the panorama.

    This view comprises more than 100 different camera pointings, with images taken through three different filters at each pointing. It is presented here as a cylindrical projection.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  3. Full-Circle Color Panorama of Phoenix Lander Deck and Landing Site on Northern Mars, Animation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image to view the animation

    This view combines more than 500 images taken after NASA's Phoenix Mars Lander arrived on an arctic plain at 68.22 degrees north latitude, 234.25 degrees east longitude on Mars.

    This movie makes a slow tour around highlights of the image including the landscape and the spacecraft's science deck.

    The full-circle panorama in approximately true color shows the polygonal patterning of ground at the landing area, similar to patterns in permafrost areas on Earth. The center of the image is the westward part of the scene. Trenches where Phoenix's robotic arm has been exposing subsurface material are visible in the right half of the image. The spacecraft's meteorology mast, topped by the telltale wind gauge, extends into the sky portion of the panorama.

    This view comprises more than 100 different Stereo Surface Imager camera pointings, with images taken through three different filters at each pointing. It is presented here as a cylindrical projection.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. Full-Circle Color Panorama of Phoenix Landing Site on Northern Mars, Polar Projection

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This view combines more than 400 images taken during the first several weeks after NASA's Phoenix Mars Lander arrived on an arctic plain at 68.22 degrees north latitude, 234.25 degrees east longitude on Mars.

    The full-circle panorama in approximately true color shows the polygonal patterning of ground at the landing area, similar to patterns in permafrost areas on Earth. South is toward the top. Trenches where Phoenix's robotic arm has been exposing subsurface material are visible in the lower half of the image. The spacecraft's meteorology mast, topped by the telltale wind gauge, extends into the sky portion of the panorama.

    This view comprises more than 100 different camera pointings, with images taken through three different filters at each pointing. It is presented here as a polar projection.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Full-Circle Color Panorama of Phoenix Landing Site on Northern Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Mission Success Pan Click on image to view the movie

    This view combines more than 400 images taken during the first several weeks after NASA's Phoenix Mars Lander arrived on an arctic plain at 68.22 degrees north latitude, 234.25 degrees east longitude on Mars.

    The movie makes a slow tour around highlights of the image.

    The full-circle panorama in approximately true color shows the polygonal patterning of ground at the landing area, similar to patterns in permafrost areas on Earth. The center of the image is the westward part of the scene. Trenches where Phoenix's robotic arm has been exposing subsurface material are visible in the right half of the image. The spacecraft's meteorology mast, topped by the telltale wind gauge, extends into the sky portion of the panorama.

    This view comprises more than 100 different camera pointings, with images taken through three different filters at each pointing. It is presented here as a cylindrical projection.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  6. Highly Heterogeneous Soil Bacterial Communities around Terra Nova Bay of Northern Victoria Land, Antarctica

    PubMed Central

    Lim, Hyoun Soo; Hong, Soon Gyu; Kim, Ji Hee; Lee, Joohan; Choi, Taejin; Ahn, Tae Seok; Kim, Ok-Sun

    2015-01-01

    Given the diminished role of biotic interactions in soils of continental Antarctica, abiotic factors are believed to play a dominant role in structuring of microbial communities. However, many ice-free regions remain unexplored, and it is unclear which environmental gradients are primarily responsible for the variations among bacterial communities. In this study, we investigated the soil bacterial community around Terra Nova Bay of Victoria Land by pyrosequencing and determined which environmental variables govern the bacterial community structure at the local scale. Six bacterial phyla, Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, Cyanobacteria, and Bacteroidetes, were dominant, but their relative abundance varied greatly across locations. Bacterial community structures were affected little by spatial distance, but structured more strongly by site, which was in accordance with the soil physicochemical compositions. At both the phylum and species levels, bacterial community structure was explained primarily by pH and water content, while certain earth elements and trace metals also played important roles in shaping community variation. The higher heterogeneity of the bacterial community structure found at this site indicates how soil bacterial communities have adapted to different compositions of edaphic variables under extreme environmental conditions. Taken together, these findings greatly advance our understanding of the adaption of soil bacterial populations to this harsh environment. PMID:25799273

  7. Soil organic matter dynamics under different land-use in grasslands in Inner Mongolia (northern China)

    NASA Astrophysics Data System (ADS)

    Zhao, L.; Wu, W.; Xu, X.; Xu, Y.

    2014-04-01

    We examined bulk soil properties and molecular biomarker distributions in surface soils from Inner Mongolia grasslands in order to understand the responses of soil organic matter to different land-use. The total of sixteen soils were collected from severely degraded grassland by overgrazing (DG), native grassland without apparent anthropogenic disturbance (NG), groundwater-sustaining grassland (GG) and restored grassland from previous potato cropland (RG). Compared to NG, soil organic carbon content was lower by 50% in DG, but higher by six-fold in GG and one-fold in RG. The δ13C values of soil organic carbon were -24.2 ± 0.6‰ in DG, -24.9 ± 0.6‰ in NG, -25.1 ± 0.1‰ in RG and -26.2 ± 0.6‰ in GG, reflecting different degradation degrees of soil organic matter or different water use efficiencies. The soils in DG contained the lowest abundance of aliphatic lipids (n-alkanes, n-alkanols, n-alkanoic acids, ω-hydroxylalkanoic acids and α-hydroxylalkanoic acids) and lignin-phenols, suggesting selective removal of these biochemically recalcitrant biomarkers with grassland degradation by microbial respiration or wind erosion. Compared to NG, the soils in GG and RG increased ω-hydroxylalkanoic acids by 60-70%, a biomarker for suberin from roots, and increased α-hydroxylalkanoic acids by 10-20%, a biomarker for both cutin and suberin. Our results demonstrate that the groundwater supply and cultivation-restoration practices in Inner Mongolia grasslands not only enhance soil organic carbon sequestration, but also change the proportions of shoot vs. root-derived carbon in soils. This finding has important implications for global carbon cycle since root derived aliphatic carbon has a longer residence time than the aboveground tissue-derived carbon in soils.

  8. Soil organic matter dynamics under different land use in grasslands in Inner Mongolia (northern China)

    NASA Astrophysics Data System (ADS)

    Zhao, L.; Wu, W.; Xu, X.; Xu, Y.

    2014-09-01

    We examined bulk soil properties and molecular biomarker distributions in surface soils from Inner Mongolian grasslands in order to understand the responses of soil organic matter to different land use. A total of 16 soils were collected from severely degraded grassland by overgrazing (DG), native grassland without apparent anthropogenic disturbance (NG), groundwater-sustaining grassland (GG) and restored grassland from previous potato cropland (RG). Compared to NG, soil organic carbon content was lower by 50% in DG, but higher by six-fold in GG and one-fold in RG. The δ13C values of soil organic carbon were -24.2 ± 0.6‰ in DG, -24.9 ± 0.6‰ in NG, -25.1 ± 0.1‰ in RG and -26.2 ± 0.6‰ in GG, reflecting different degradation degrees of soil organic matter or different water use efficiencies. The soils in DG contained the lowest abundance of aliphatic lipids (n-alkanes, n-alkanols, n-alkanoic acids, ω-hydroxylalkanoic acids and α-hydroxyalkanoic acids) and lignin-phenols, suggesting selective removal of these biochemically recalcitrant biomarkers with grassland degradation by microbial respiration or wind erosion. Compared to NG, the soils in GG and RG increased ω-hydroxylalkanoic acids by 60-70%, a biomarker for suberin from roots, and increased α-hydroxylalkanoic acids by 10-20%, a biomarker for both cutin and suberin. Our results demonstrate that the groundwater supply and cultivation-restoration practices in Inner Mongolian grasslands not only enhance soil organic carbon sequestration, but also change the proportions of shoot- versus root-derived carbon in soils. This finding has important implications for the global carbon cycle since root-derived aliphatic carbon has a longer residence time than the aboveground tissue-derived carbon in soils.

  9. Estuarine infill and coastal progradation, southern van diemen gulf, northern Australia

    NASA Astrophysics Data System (ADS)

    Woodroffe, C. D.; Mulrennan, M. E.; Chappell, J.

    1993-03-01

    There are several estuaries associated with the pronouncedly seasonal rivers which drain northwards from the Middle Proterozoic sandstone Arnhem Land plateau, and the Tertiary Koolpinyah land surface, into the macrotidal van Diemen Gulf, in the Northern Territory of Australia. The Holocene development of these, investigated in greatest detail for the South Alligator River with an upland catchment of > 10,000 km 2. through drilling, palynology and radiocarbon dating, comprises both estuarine infill and coastal progradation. Three phases of estuarine infill can be recognised: (i) a transgressive phase (8000-6800 years B.P.) of marine incursion; (ii) a big swamp phase (6800-5300 years B.P.) of widespread mangrove forest development; and (iii) a sinuous/cuspate phase of floodplain development since 5300 years B.P., during which the tidal river has meandered and reworked earlier estuarine sediments. Since 6000 years B.P., the South Alligator coastal plain has prograded at a decelerating rate, with two phases of chenier ridge formation. A similar pattern of estuarine infill, and decelerating coastal plain progradation, is demonstrated for the Adelaide and Mary Rivers, both with catchments of > 6000 km 2. The southern shore of van Diemem Gulf appears to have changed its overall position little during the last 2000 years. The major source for the clay, silt and fine sands which have infilled the estuary and coastal plain has been from seaward. Dispite the similarity of development, coastal sediment build up has had different effects on the morphology of each tidal river. The Adelaide has undergone a major diversion and no longer flows directly into van Diemen Gulf, but occupies a former fluvial course, and the Mary has been blocked entirely, and its former estuarine palaeochannels have been infilled with tide-transported sediment.

  10. Coldest Temperature Extreme Monotonically Increased and Hottest Extreme Oscillated over Northern Hemisphere Land during Last 114 Years

    PubMed Central

    Zhou, Chunlüe; Wang, Kaicun

    2016-01-01

    Most studies on global warming rely on global mean surface temperature, whose change is jointly determined by anthropogenic greenhouse gases (GHGs) and natural variability. This introduces a heated debate on whether there is a recent warming hiatus and what caused the hiatus. Here, we presented a novel method and applied it to a 5° × 5° grid of Northern Hemisphere land for the period 1900 to 2013. Our results show that the coldest 5% of minimum temperature anomalies (the coldest deviation) have increased monotonically by 0.22 °C/decade, which reflects well the elevated anthropogenic GHG effect. The warmest 5% of maximum temperature anomalies (the warmest deviation), however, display a significant oscillation following the Atlantic Multidecadal Oscillation (AMO), with a warming rate of 0.07 °C/decade from 1900 to 2013. The warmest (0.34 °C/decade) and coldest deviations (0.25 °C/decade) increased at much higher rates over the most recent decade than last century mean values, indicating the hiatus should not be interpreted as a general slowing of climate change. The significant oscillation of the warmest deviation provides an extension of previous study reporting no pause in the hottest temperature extremes since 1979, and first uncovers its increase from 1900 to 1939 and decrease from 1940 to 1969. PMID:27172861

  11. Spatial scale-dependent land-atmospheric methane exchange in the northern high latitudes from 1993 to 2004

    NASA Astrophysics Data System (ADS)

    Zhu, X.; Zhuang, Q.; Lu, X.; Song, L.

    2013-11-01

    Effects of various spatial scales of water table dynamics on the land-atmospheric methane (CH4) exchange have not yet been assessed for large regions. Here we used a coupled hydrology-biogeochemistry model to quantify daily CH4 exchange over the pan-Arctic from 1993 to 2004 at two spatial scales (100 km and 5 km). The effects of sub-grid spatial variability of the water table depth (WTD) on CH4 emissions were examined with a TOPMODEL-based parameterization scheme for northern high latitudes regions. Our results indicate that 5 km CH4 emissions (38.1-55.4 Tg CH4 yr-1, considering the spatial heterogeneity of WTD) were 42% larger than 100 km CH4 emissions (using grid-cell-mean WTD) and the differences in annual CH4 emissions were due to increased emitting area and enhanced flux density after WTD redistribution. Further, the inclusion of sub-grid WTD spatial heterogeneity also influences the inter-annual variability of CH4 emissions. Soil temperature plays a more important role in the 100 km estimates, while the 5 km estimates are more influenced by WTD. This study suggests that previous macro-scale biogeochemical models using grid-cell-mean WTD might have underestimated the regional CH4 budget. The spatial scale-dependent effects of WTD should be considered in future quantifications of regional CH4 emissions.

  12. Coldest Temperature Extreme Monotonically Increased and Hottest Extreme Oscillated over Northern Hemisphere Land during Last 114 Years

    NASA Astrophysics Data System (ADS)

    Zhou, Chunlüe; Wang, Kaicun

    2016-05-01

    Most studies on global warming rely on global mean surface temperature, whose change is jointly determined by anthropogenic greenhouse gases (GHGs) and natural variability. This introduces a heated debate on whether there is a recent warming hiatus and what caused the hiatus. Here, we presented a novel method and applied it to a 5° × 5° grid of Northern Hemisphere land for the period 1900 to 2013. Our results show that the coldest 5% of minimum temperature anomalies (the coldest deviation) have increased monotonically by 0.22 °C/decade, which reflects well the elevated anthropogenic GHG effect. The warmest 5% of maximum temperature anomalies (the warmest deviation), however, display a significant oscillation following the Atlantic Multidecadal Oscillation (AMO), with a warming rate of 0.07 °C/decade from 1900 to 2013. The warmest (0.34 °C/decade) and coldest deviations (0.25 °C/decade) increased at much higher rates over the most recent decade than last century mean values, indicating the hiatus should not be interpreted as a general slowing of climate change. The significant oscillation of the warmest deviation provides an extension of previous study reporting no pause in the hottest temperature extremes since 1979, and first uncovers its increase from 1900 to 1939 and decrease from 1940 to 1969.

  13. Coldest Temperature Extreme Monotonically Increased and Hottest Extreme Oscillated over Northern Hemisphere Land during Last 114 Years.

    PubMed

    Zhou, Chunlüe; Wang, Kaicun

    2016-01-01

    Most studies on global warming rely on global mean surface temperature, whose change is jointly determined by anthropogenic greenhouse gases (GHGs) and natural variability. This introduces a heated debate on whether there is a recent warming hiatus and what caused the hiatus. Here, we presented a novel method and applied it to a 5° × 5° grid of Northern Hemisphere land for the period 1900 to 2013. Our results show that the coldest 5% of minimum temperature anomalies (the coldest deviation) have increased monotonically by 0.22 °C/decade, which reflects well the elevated anthropogenic GHG effect. The warmest 5% of maximum temperature anomalies (the warmest deviation), however, display a significant oscillation following the Atlantic Multidecadal Oscillation (AMO), with a warming rate of 0.07 °C/decade from 1900 to 2013. The warmest (0.34 °C/decade) and coldest deviations (0.25 °C/decade) increased at much higher rates over the most recent decade than last century mean values, indicating the hiatus should not be interpreted as a general slowing of climate change. The significant oscillation of the warmest deviation provides an extension of previous study reporting no pause in the hottest temperature extremes since 1979, and first uncovers its increase from 1900 to 1939 and decrease from 1940 to 1969. PMID:27172861

  14. Coldest Temperature Extreme Monotonically Increased and Hottest Extreme Oscillated over Northern Hemisphere Land during Last 114 Years

    NASA Astrophysics Data System (ADS)

    Zhou, Chunlüe; Wang, Kaicun

    2016-04-01

    Most studies on global warming rely on global mean surface temperature, whose change is jointly determined by anthropogenic greenhouse gases (GHGs) and natural variability. This introduces a heated debate on whether there is a recent warming hiatus and what caused the hiatus. Here, we presented a novel method and applied it to a 5°×5° grid of Northern Hemisphere land for the period 1900 to 2013. Our results show that the coldest 5% minimum temperature anomalies (the coldest deviation) have increased monotonically by 0.22 °C/decade, which reflects well the elevated anthropogenic GHG effect. The warmest 5% maximum temperature anomalies (the warmest deviation), however, display a significant oscillation following the Atlantic Multidecadal Oscillation (AMO), with a warming rate of 0.07 °C/decade from 1900 to 2013. The warmest (0.34 °C/decade) and coldest deviations (0.25 °C/decade) increased at much higher rates over the most recent decade than last century mean values, indicating the hiatus should not be interpreted as a general slowing of climate change. The significant oscillation of the warmest deviation provides an extension of previous study reporting no pause in the hottest temperature extremes since 1979, and first uncovers its increase from 1900 to 1939 and decrease from 1940 to 1969.

  15. How rural land use management facilitates drought risk adaptation in a changing climate - A case study in arid northern China.

    PubMed

    Lei, Yongdeng; Zhang, Hailin; Chen, Fu; Zhang, Linbo

    2016-04-15

    Under a warming climate, frequent drought and water scarcity in northern China have severely disrupted agricultural production and posed a substantial threat to farmers' livelihoods. Based on first-hand data collected through in-depth interviews with local managers and farmer households, this study evaluated the effectiveness of rural land use management in mitigating drought risk, ensuring food security and improving farmers' livelihoods. Our findings indicate that a) reforestation on low-yield cropland not only can improve the eco-environment but can also prominently mitigate the production risk to local farmers; b) replacing the traditional border irrigation with sprinkler irrigation has substantially curbed agricultural water usage and increased the per unit of output; and c) in recent years, instead of planting water-intensive grain crops, local farmers cultivated more forage crops to raise animals, which greatly diversified their income sources and reduced the drought risk of agricultural production. By performing an empirical case study in drought-prone Inner Mongolia, this study provides decision-makers with insights into how to strategically adapt to drought risk and reduce rural poverty within the broader context of climate change. PMID:26815296

  16. Vegetation pattern variation, soil degradation and their relationship along a grassland desertification gradient in Horqin Sandy Land, northern China

    NASA Astrophysics Data System (ADS)

    Zuo, Xiaoan; Zhao, Halin; Zhao, Xueyong; Guo, Yirui; Yun, Jianying; Wang, Shaokun; Miyasaka, Takafumi

    2009-09-01

    The Horqin Sandy Land is one of the most severely desertified regions in northern China. Plant communities and soil conditions at five stages of grassland desertification (potential, light, moderate, severe and very severe) were selected for the study of vegetation pattern variation relating to soil degradation. The results showed that vegetation cover, species richness and diversity, aboveground biomass (AGB), underground biomass, litter, soil organic carbon (C), total nitrogen (N), total phosphorus (P), electrical conductivity, very fine sand (0.1-0.05 mm) content and silt (0.05-0.002 mm) content decreased with the desertification development. Plant community succession presented that the palatable herbaceous plants gave place to the shrub species with asexual reproduction and sand pioneer plants. The decline of vegetation cover and AGB was positively related to the loss of soil organic C and total N with progressive desertification ( P < 0.01). The multivariate statistical analysis showed that plant community distribution, species diversity and ecological dominance had the close relationship with the gradient of soil nutrients in the processes of grassland desertification. These results suggest that grassland desertification results in the variation of vegetation pattern which presents the different composition and structure of plant community highly influenced by the soil properties.

  17. Effects of land-conversion in a biosphere-atmosphere model of Northern South America - Part 1: Regional differences in hydrometeorology

    NASA Astrophysics Data System (ADS)

    Knox, R. G.; Longo, M.; Swann, A. L. S.; Zhang, K.; Levine, N. M.; Moorcroft, P. R.; Bras, R. L.

    2013-12-01

    This work investigates how landuse changes over northern South America, driven by human interventions, have affected the regional patterns of hydrology. Comparisons are made to scenarios where no human disturbance of the regional vegetation is assumed. A numerical model of the terrestrial biosphere (Ecosystem Demography Model 2 - ED2) is combined with an atmospheric model (Brazilian Regional Atmospheric Modeling System - BRAMS) to investigate how land conversion in the Amazon and Northern South America have changed the hydrology of the region. Two numerical realizations of the structure and composition of terrestrial vegetation are used as boundary conditions in a simulation of the regional land surface and atmosphere. One realization seeks to capture the present day vegetation condition that includes deforestation and land-conversion, the other is an estimate of the potential structure and composition of the region without human influence. Model output is assessed for consistent and significant pattern differences in hydrometeorology. Results show that South American land conversion has a consistent impact on the regional patterning of precipitation. Land-conversion was not associated with a significant bias in continental mean precipitation, but was associated with a negative bias in mean continental evaporation and a positive bias in continental runoff. A companion paper continues this analysis, with case studies that focus on specific areas that show significant differential hydrologic response.

  18. Multiple shallow level sill intrusions coupled with hydromagmatic explosive eruptions marked the initial phase of Ferrar large igneous province magmatism in northern Victoria Land, Antarctica

    USGS Publications Warehouse

    Viereck-Goette, L.; Schöner, R.; Bomfleur, B.; Schneider, J.

    2007-01-01

    Field data gathered during GANOVEX IX (2005/2006) in Northern Victoria Land, Antarctica, indicate that volcaniclastic deposits of phreatomagmatic eruptions (so-called Exposure Hill Type events) are intercalated with fluvial deposits of Triassic-Jurassic age at two stratigraphic levels. Abundant scoriaceous spatter (locally welded) indicates a hawaiian/strombolian component. Breccia-filled diatremes, from which volcaniclastic deposits were sourced, are rooted in sills which intruded wet sediments. The deposits are thus subaerial expressions of initial Ferrar magmatism involving intrusion of multiple shallow-level sills. Due to magma-sediment interaction abundant clastic dikes are developed that intrude the sediments and sills. All igneous components in the volcaniclastic deposits are andesitic in composition, as are the chilled margins of the sills. They are more differentiated than the basaltic andesites of the younger effusive section of Kirkpatrick plateau lavas which in northern Victoria Land start with pillow lavas and small volume lava flows from volcanic necks.

  19. Land use changes and its driving forces in hilly ecological restoration area based on gis and rs of northern china

    PubMed Central

    Gao, Peng; Niu, Xiang; Wang, Bing; Zheng, Yunlong

    2015-01-01

    Land use change is one of the important aspects of the regional ecological restoration research. With remote sensing (RS) image in 2003, 2007 and 2012, using geographic information system (GIS) technologies, the land use pattern changes in Yimeng Mountain ecological restoration area in China and its driving force factors were studied. Results showed that: (1) Cultivated land constituted the largest area during 10 years, and followed by forest land and grass land; cultivated land and unused land were reduced by 28.43% and 44.32%, whereas forest land, water area and land for water facilities and others were increased. (2) During 2003–2007, forest land change showed the largest, followed by unused land and grass land; however, during 2008–2012, water area and land for water facilities change showed the largest, followed by grass land and unused land. (3) Land use degree was above the average level, it was in the developing period during 2003–2007 and in the degenerating period during 2008–2012. (4) Ecological Restoration Projects can greatly change the micro topography, increase vegetation coverage, and then induce significant changes in the land use distribution, which were the main driving force factors of the land use pattern change in the ecological restoration area. PMID:26047160

  20. Simulated impact of past and possible future land use changes on the hydrological response of the Northern German lowland ‘Hunte’ catchment

    NASA Astrophysics Data System (ADS)

    Elfert, Simon; Bormann, Helge

    2010-03-01

    SummaryLand use is a key factor controlling the hydrological behaviour of catchments. Changing land use therefore can have an important influence on the local hydrological cycle. Validated and process-based hydrological models are suitable tools to quantify the impact of a change in land use on the hydrological processes. In this study, the physically based catchment model WaSiM-ETH (Water Balance Simulation Model) was applied to a mesoscale lowland catchment in northern Germany (Hunte river, 2141 km 2 at gauge Oldenburg). Model calibration and validation showed that WaSiM-ETH well represented the discharge of the main Hunte river while the discharge dynamics of a few lowland tributaries whose catchments are characterised by peaty soils and intense artificial drainage could not be represented. The purpose of this study was twofold; on the one hand to analyse the sensitivity of WaSiM-ETH to changes in land use observed in the decade 1990-2000, and on the other hand to quantify the impact of land use change projected for the future in terms of land use scenarios available to the public. The results showed that WaSiM-ETH is hardly sensitive to the slight changes observed in the last decade of the 20th century. By contrast, water flows simulated by WaSiM-ETH are clearly impacted by agricultural land use scenarios which were developed based on IPCC scenarios. However, the results also show that it is not sufficient to focus on agricultural land use, only. The proposed reduction of agricultural land leaves open the final land cover after land use change, e.g., forest or urban areas. This study demonstrated that WaSiM-ETH was more sensitive to the choice of the final land cover than to the difference in the scenarios (e.g., A1F1 versus B1). Therefore, we recommend to precisely define change in agricultural land use as well as the final land cover in order to estimate the realistic impact of land use change on hydrological behaviour.

  1. Spatial scale-dependent land-atmospheric methane exchanges in the northern high latitudes from 1993 to 2004

    NASA Astrophysics Data System (ADS)

    Zhu, X.; Zhuang, Q.; Lu, X.; Song, L.

    2014-04-01

    Effects of various spatial scales of water table dynamics on land-atmospheric methane (CH4) exchanges have not yet been assessed for large regions. Here we used a coupled hydrology-biogeochemistry model to quantify daily CH4 exchanges over the pan-Arctic from 1993 to 2004 at two spatial scales of 100 km and 5 km. The effects of sub-grid spatial variability of the water table depth (WTD) on CH4 emissions were examined with a TOPMODEL-based parameterization scheme for the northern high latitudes. We found that both WTD and CH4 emissions are better simulated at a 5 km spatial resolution. By considering the spatial heterogeneity of WTD, net regional CH4 emissions at a 5 km resolution are 38.1-55.4 Tg CH4 yr-1 from 1993 to 2004, which are on average 42% larger than those simulated at a 100 km resolution using a grid-cell-mean WTD scheme. The difference in annual CH4 emissions is attributed to the increased emitting area and enhanced flux density with finer resolution for WTD. Further, the inclusion of sub-grid WTD spatial heterogeneity also influences the inter-annual variability of CH4 emissions. Soil temperature plays an important role in the 100 km estimates, while the 5 km estimates are mainly influenced by WTD. This study suggests that previous macro-scale biogeochemical models using a grid-cell-mean WTD scheme might have underestimated the regional CH4 emissions. The spatial scale-dependent effects of WTD should be considered in future quantification of regional CH4 emissions.

  2. Integrated approaches to restore gullies in land prone to soil piping: innovations from the drylands of northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Frankl, Amaury; Deckers, Jozef; Moulaert, Lys; Van Damme, Alexander; Haile, Mitiku; Poesen, Jean; Nyssen, Jan

    2014-05-01

    Multiple on-site and off-site effects of gully erosion threaten sustainable development, which is especially evident in dryland environments. To control soil erosion by gullying, various soil and water conservation measures have been developed, of which check dams are the most common. Where soil piping occurs, soil and water conservation measures have limited effect on gully stabilization, and check dams easily collapse. Therefore, new integrated approaches are needed to control gully erosion induced by soil piping. Here, a subsurface geomembrane dam is proposed as an innovative measure to reduce subsurface flow in soil pipes near gullies. Application of such a dam in Northern Ethiopia, resulted in a decrease of gully erosion rates in Vertisols, and a rising water table in the intergully areas near the gully channel. The consequence of this effect for agriculture near gully channels is the reduction of soil desiccation and hence, increased crop yields in the intergully areas near the gully channels. With the gully filling and stabilizing, runoff water could be diverted into adjacent land, offering additional benefits to the local communities. Here, the runoff diversion was done into a vegetation protection site, in order to enhances biomass production, especially tree growth. Moreover, a water collection pound was created to make water available in the prolonged dry season. These interventions support additional economical activities such as beekeeping and the establishment of a tree nursery. With the multiple on-site and off-site benefits of the integrated approach, local communities have a better guarantee of investment return and livelihood improvement, increasing their support to gully rehabilitation schemes. Keywords: Crop, Subsurface dam, Soil and water conservation, Tree growth, Vertisol, Dryland.

  3. Crustal structure of a land-ocean transitional zone in the northern South China Sea, from an onshore-offshore seismic survey

    NASA Astrophysics Data System (ADS)

    Cao, J.; Xia, S.; Xu, H.; Sun, J.

    2012-12-01

    The littoral fault zone(LFZ), a east-northeast-trending rupture region, which is located at an land-ocean transition area in the northern margin of South China Sea(SCS). Previous work in the northern SCS identified the LFZ as the most hazardous fault in the coastal South China, in history distribution of destructive erathquakes with magnitudes greater than 7.0 occured almost all along the LFZ. But in the maritime space off the Pearl River Mouth(PRM), the LFZ is intersected with a northwest-trending fault zone, where the seismic activity level to be significantly lower in recent hundreds of years, therefore it is very important to obtain detailed deep seismogenic structure in this potential strong earthquake zone. To investigate the crustal structure of the LFZ and the potential strong earthquake zone off the PMR, a wide-angle onshore-offshore seismic experiment and a coincident multi-channel seismic(MCS) profile were carried out in the northern SCS during July and August, 2010. The seismic source was an array of four guns and the shots were recorded simultaneously by ocean bottom seismometers and portable and permanent land stations. The preliminary processing result demonstrated good quality data, clear shallow-crustal structure is obtained from the MCS data, and the permanent seismic stations received air-gun signals over a distance of 360 km. Observed and calculated P-wave traveltimes were matched by forwad modelling prior to the inversion. Finally we got the optimal two-dimensional P-wave velocity model, and the model cross the northern margin of SCS shows the Moho depth is gradually thinned from land to sea, and the LFZ is a 10 km wide low-velocity rupture zone.

  4. Northern Cheyenne Lands Act

    THOMAS, 113th Congress

    Sen. Walsh, John E. [D-MT

    2014-06-05

    12/12/2014 By Senator Tester from Committee on Indian Affairs filed written report. Report No. 113-317. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  5. Redox state of subcontinental lithospheric mantle and relationships with metasomatism: insights from spinel peridotites from northern Victoria Land (Antarctica)

    NASA Astrophysics Data System (ADS)

    Perinelli, Cristina; Andreozzi, Giovanni B.; Conte, Aida M.; Oberti, Roberta; Armienti, Pietro

    2012-12-01

    Rift-related Cenozoic alkaline mafic lavas from northern Victoria Land (Antarctica) carry abundant mantle xenoliths whose oxygen fugacities ( fO2) were determined to assess how the metasomatism, related to Cenozoic magmatism, affected the state of oxidation of the lithospheric mantle. The xenoliths used for this study are anhydrous spinel peridotites sampled in two localities, Greene Point and Baker Rocks, that show different extents of metasomatism: these are limited to incompatible element enrichments in Greene Point and to enrichments in major, minor and trace elements at Baker Rocks. The data set includes a composite xenolith from Baker Rocks, formed by a depleted lherzolite crosscut by an amphibole-bearing vein. Mössbauer spectroscopy was used to accurately determine the Fe3+/Fetot ratios in spinel and amphibole minerals. Amphiboles were also characterized by Single-Crystal X-ray Diffraction, and the crystallographic data were used to calculate the dehydrogenation. The oxidation state recorded by the xenoliths ranges from 0.2 to 1.5 log-bar units below the fayalite-magnetite-quartz (FMQ) buffer (Δlog fO2) with the highest values observed in the metasomatized samples from Greene Point. For the vein of composite Baker Rocks xenolith, Δlog fO2 was estimated on the basis of the amphibole in -1.7 log-bar units, a value close to those calculated for all Baker Rocks xenoliths (Δlog fO2 = -1.5 to -1.1 log-bar units). These results indicate a similar oxidation state for lithospheric mantle prior to the metasomatic event at Greene Point and Baker Rocks (Δlog fO2 ~ -1.3 log-bar units). Metasomatism produced different effects in the shallow mantle at the two sites. At Greene Point, an oxidizing metasomatic melt caused the rise of fO2 in peridotite portions close to melt conduits up to FMQ. In contrast, at Baker Rocks, a metasomatizing melt with fO2 similar to that of the peridotite matrix produced chemical changes in the surrounding mantle rocks and amphibole

  6. Analysis of Land Covers over Northern Peninsular Malaysia by Using ALOS-PALSAR Data Based on Frequency-Based Contextual and Neural Network Classification Technique

    NASA Astrophysics Data System (ADS)

    Lim, H. S.; MatJafri, M. Z.; Abdullah, K.; Saleh, N. Mohd.

    2008-11-01

    Optical and microwave remote sensing data have been widely used in land cover and land use classification. Optical satellite remote sensing methods are more appropriate but require cloud-free conditions for data to be useful especially at Equatorial region. In Equatorial region cloud free acquisitions can be rare reducing these sensors' applicability to such studies. ALOS-PALSAR data can be acquired day and night irrespective of weather conditions. This paper presents a comparison between frequency-based contextual and neural network classification technique by using ALOS-PALSAR data for land cover assessment in Northern Peninsular Malaysia. The ALOS-PALSAR data acquired on 10 November 2006 were converted to vegetation, urban, water and other land features. The PALSAR data of training areas were choose and selected based on the optical satellite imagery and were classified using supervised classification methods. Supervised classification techniques were used in the classification analysis. The best supervised classifier was chosen based on the highest overall accuracy and Kappa statistic. Based on the result produced by this study, it can be pointed out the utility of ALOS-PALSAR data as an alternative data source for land cover classification in the Peninsular Malaysia.

  7. [Effects of climate and land use change on the changes of vegetation coverage in farming-pastoral ecotone of Northern China].

    PubMed

    Liu, Jun-Hui; Gao, Ji-Xi

    2008-09-01

    Based on the remote sensing images and the meteorological data in 1986 and 2000, and by using the model of extracting vegetation coverage, the spatiotemporal changes of vegetation coverage in the farming-pastoral ecotone of Northern China in 1986-2000 were studied, with the effects of climate and land use change on the changes analyzed. The results showed that in this ecotone, the area with lower vegetation coverage was increasing, while that with higher vegetation coverage was in adverse. The regions with increasing vegetation coverage were mainly in the east of northeast section, the west of north section, and the west of northwest section of the ecotone, while the vegetation coverage in the other sections was obviously degraded. The vegetation coverage were positively correlated with precipitation and aridity index, but negatively correlated with temperature. The change direction and extent of the vegetation coverage varied with land use types. PMID:19102318

  8. Comparison of evapotranspiration components and water-use efficiency among different land use patterns of temperate steppe in the Northern China pastoral-farming ecotone

    NASA Astrophysics Data System (ADS)

    Li, Yuzhe; Fan, Jiangwen; Hu, Zhongmin; Shao, Quanqin; Harris, Warwick

    2016-06-01

    Water-use efficiency (WUE), which links carbon and water cycles, is an important indicator of assessing the interactions between ecosystems and regional climate. Using chamber methods with and without plant removal treatments, we investigated WUE and evapotranspiration (ET) components in three ecosystems with different land-use types in Northern China pastoral-farming ecotone. In comparison, ET of the ecosystems with grazing exclusion and cultivating was 6.7 and 13.4 % higher than that of the ecosystem with free grazing. The difference in ET was primarily due to the different magnitudes of soil water evaporation (E) rather than canopy transpiration (T). Canopy WUE (WUEc, i.e., the ratio of gross primary productivity to T) at the grazing excluded and cultivated sites was 17 and 36 % higher than that at the grazing site. Ecosystem WUE (WUEnep, i.e., the ratio of net ecosystem productivity to ET) at the cultivated site was 34 and 28 % lower in comparison with grazed and grazing excluded stepped, respectively. The varied leaf area index (LAI) of different land uses was correlated with microclimate and ecosystem vapor/carbon exchange. The LAI changing with land uses should be the primary regulation of grassland WUE. These findings facilitate the mechanistic understanding of carbon-water relationships at canopy and ecosystem levels and projection of the effects of land-use change on regional climate and productivity.

  9. Comparison of evapotranspiration components and water-use efficiency among different land use patterns of temperate steppe in the Northern China pastoral-farming ecotone

    NASA Astrophysics Data System (ADS)

    Li, Yuzhe; Fan, Jiangwen; Hu, Zhongmin; Shao, Quanqin; Harris, Warwick

    2015-10-01

    Water-use efficiency (WUE), which links carbon and water cycles, is an important indicator of assessing the interactions between ecosystems and regional climate. Using chamber methods with and without plant removal treatments, we investigated WUE and evapotranspiration (ET) components in three ecosystems with different land-use types in Northern China pastoral-farming ecotone. In comparison, ET of the ecosystems with grazing exclusion and cultivating was 6.7 and 13.4 % higher than that of the ecosystem with free grazing. The difference in ET was primarily due to the different magnitudes of soil water evaporation (E) rather than canopy transpiration (T). Canopy WUE (WUEc, i.e., the ratio of gross primary productivity to T) at the grazing excluded and cultivated sites was 17 and 36 % higher than that at the grazing site. Ecosystem WUE (WUEnep, i.e., the ratio of net ecosystem productivity to ET) at the cultivated site was 34 and 28 % lower in comparison with grazed and grazing excluded stepped, respectively. The varied leaf area index (LAI) of different land uses was correlated with microclimate and ecosystem vapor/carbon exchange. The LAI changing with land uses should be the primary regulation of grassland WUE. These findings facilitate the mechanistic understanding of carbon-water relationships at canopy and ecosystem levels and projection of the effects of land-use change on regional climate and productivity.

  10. Comparison of evapotranspiration components and water-use efficiency among different land use patterns of temperate steppe in the Northern China pastoral-farming ecotone.

    PubMed

    Li, Yuzhe; Fan, Jiangwen; Hu, Zhongmin; Shao, Quanqin; Harris, Warwick

    2016-06-01

    Water-use efficiency (WUE), which links carbon and water cycles, is an important indicator of assessing the interactions between ecosystems and regional climate. Using chamber methods with and without plant removal treatments, we investigated WUE and evapotranspiration (ET) components in three ecosystems with different land-use types in Northern China pastoral-farming ecotone. In comparison, ET of the ecosystems with grazing exclusion and cultivating was 6.7 and 13.4 % higher than that of the ecosystem with free grazing. The difference in ET was primarily due to the different magnitudes of soil water evaporation (E) rather than canopy transpiration (T). Canopy WUE (WUEc, i.e., the ratio of gross primary productivity to T) at the grazing excluded and cultivated sites was 17 and 36 % higher than that at the grazing site. Ecosystem WUE (WUEnep, i.e., the ratio of net ecosystem productivity to ET) at the cultivated site was 34 and 28 % lower in comparison with grazed and grazing excluded stepped, respectively. The varied leaf area index (LAI) of different land uses was correlated with microclimate and ecosystem vapor/carbon exchange. The LAI changing with land uses should be the primary regulation of grassland WUE. These findings facilitate the mechanistic understanding of carbon-water relationships at canopy and ecosystem levels and projection of the effects of land-use change on regional climate and productivity. PMID:26449350

  11. 76 FR 66321 - Long Range Transportation Plan for Fish and Wildlife Service Lands in Hawai`i, Idaho, Northern...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    .... SUPPLEMENTARY INFORMATION: On October 18, 2011, via a Federal Register notice (76 FR 64376), we announced the... Fish and Wildlife Service Long Range Transportation Plan for Fish and Wildlife Service Lands in Hawai`i... availability of the final draft Long Range Transportation Plan (LRTP) for our lands in Hawai`i, Idaho,...

  12. Investigating the interactions between biogeophysical and biogeochemical processes in the northern high latitudes using a land surface model; feedbacks and climatic impacts

    NASA Astrophysics Data System (ADS)

    Barman, R.; Jain, A.; Liang, M.; McGuire, A. D.

    2010-12-01

    northern high latitude region. Efforts are currently underway to couple the ISAM with the newly released Community Earth System Model (CESM1) to study land-atmosphere interactions in northern high latitudes, specifically for the permafrost dominated regions, and to investigate the associated future climatic impacts.

  13. Impact of past and possible future land use changes on the hydrological behaviour of the Northern German lowland `Hunte' river

    NASA Astrophysics Data System (ADS)

    Bormann, H.; Elfert, S.

    2009-04-01

    Changing hydrological behaviour of catchments can be driven by several different influencing factors: e.g., climate change, water management and land use change. While changes in climate and water management directly affect the water cycle be changes in regional forcing (e.g., precipitation, radiation) and local management of surface and subsurface waters, the impact of land use changes on catchment hydrology is much more complex to assess as it results from regionally distributed local changes. Therefore, spatially distributed and process based hydrological catchment models are required for assessing the impacts of spatially distributed land use changes. The Hunte catchment in Lower Saxony is part of an intensively agriculturally used landscape in Northwest Germany. Pasture and cropland are dominating land uses, while surface sealing increases due to urban sprawl. As the catchment is dominated by agricultural landuse mostly, it can be expected that European and national policy as well as the agroeconomic development can strongly effect the land use distribution in future. Therefore, in this study, the effect of historical and projected land use changes on the catchment hydrological behaviour is assessed the process based catchment model WASIM-ETH (Schulla). WASIM-ETH has been applied to observed land use data sets (CORINE data) and projected land use scenarios (based on Ewert et al., 2005; Rounsevell et al., 2005) for the mesoscale catchment of the Hunte river in order to quantify the sensitivity with respect to land use change. The results of the study show that historical land use changes have almost no impact on the catchment hydrological processes in Northwest Germany. Simulated water balances and runoff hydrographs are almost identical, driving the model with different input data sets based on the CORINE data set. Differences are small compared to trends identified in the discharge data of the Hunte and Weser rivers. However, in relation to the ability of

  14. Increased terrestrial to ocean sediment and carbon fluxes in the northern Chesapeake Bay associated with twentieth century land alteration

    USGS Publications Warehouse

    Saenger, C.; Cronin, T. M.; Willard, D.; Halka, J.; Kerhin, R.

    2008-01-01

    We calculated Chesapeake Bay (CB) sediment and carbon fluxes before and after major anthropogenic land clearance using robust monitoring, modeling and sedimentary data. Four distinct fluxes in the estuarine system were considered including (1) the flux of eroded material from the watershed to streams, (2) the flux of suspended sediment at river fall lines, (3) the burial flux in tributary sediments, and (4) the burial flux in main CB sediments. The sedimentary maximum in Ambrosia (ragweed) pollen marked peak land clearance (~1900 a.d.). Rivers feeding CB had a total organic carbon (TOC)/total suspended solids of 0.24??0.12, and we used this observation to calculate TOC fluxes from sediment fluxes. Sediment and carbon fluxes increased by 138-269% across all four regions after land clearance. Our results demonstrate that sediment delivery to CB is subject to significant lags and that excess post-land clearance sediment loads have not reached the ocean. Post-land clearance increases in erosional flux from watersheds, and burial in estuaries are important processes that must be considered to calculate accurate global sediment and carbon budgets. ?? 2008 Coastal and Estuarine Research Federation.

  15. Methane uptake by four land-use types in the agro-pastoral region of northern China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land-use types and management practices of temperate semiarid steppes may affect soil sink activity for atmospheric methane (CH4). Most prevous studies related to CH4 have focused primarily on the growing season with only a few studies evaluating CH4 fluxes throughout the entire year. With CH4 exc...

  16. Global sea-level rise is recognised, but flooding from anthropogenic land subsidence is ignored around northern Manila Bay, Philippines.

    PubMed

    Rodolfo, Kelvin S; Siringan, Fernando P

    2006-03-01

    Land subsidence resulting from excessive extraction of groundwater is particularly acute in East Asian countries. Some Philippine government sectors have begun to recognise that the sea-level rise of one to three millimetres per year due to global warming is a cause of worsening floods around Manila Bay, but are oblivious to, or ignore, the principal reason: excessive groundwater extraction is lowering the land surface by several centimetres to more than a decimetre per year. Such ignorance allows the government to treat flooding as a lesser problem that can be mitigated through large infrastructural projects that are both ineffective and vulnerable to corruption. Money would be better spent on preventing the subsidence by reducing groundwater pumping and moderating population growth and land use, but these approaches are politically and psychologically unacceptable. Even if groundwater use is greatly reduced and enlightened land-use practices are initiated, natural deltaic subsidence and global sea-level rise will continue to aggravate flooding, although at substantially lower rates. PMID:16512865

  17. Unraveling Landscape Complexity: Land Use/Land Cover Changes and Landscape Pattern Dynamics (1954-2008) in Contrasting Peri-Urban and Agro-Forest Regions of Northern Italy

    NASA Astrophysics Data System (ADS)

    Smiraglia, D.; Ceccarelli, T.; Bajocco, S.; Perini, L.; Salvati, L.

    2015-10-01

    This study implements an exploratory data analysis of landscape metrics and a change detection analysis of land use and population density to assess landscape dynamics (1954-2008) in two physiographic zones (plain and hilly-mountain area) of Emilia Romagna, northern Italy. The two areas are characterized by different landscape types: a mixed urban-rural landscape dominated by arable land and peri-urban settlements in the plain and a traditional agro-forest landscape in the hilly-mountain area with deciduous and conifer forests, scrublands, meadows, and crop mosaic. Urbanization and, to a lesser extent, agricultural intensification were identified as the processes underlying landscape change in the plain. Land abandonment determining natural forestation and re-forestation driven by man was identified as the process of change most representative of the hilly-mountain area. Trends in landscape metrics indicate a shift toward more fragmented and convoluted patterns in both areas. Number of patches, the interspersion and juxtaposition index, and the large patch index are the metrics discriminating the two areas in terms of landscape patterns in 1954. In 2008, mean patch size, edge density, interspersion and juxtaposition index, and mean Euclidean nearest neighbor distance were the metrics with the most different spatial patterns in the two areas. The exploratory data analysis of landscape metrics contributed to link changes over time in both landscape composition and configuration providing a comprehensive picture of landscape transformations in a wealthy European region. Evidence from this study are hoped to inform sustainable land management designed for homogeneous landscape units in similar socioeconomic contexts.

  18. Late Miocene terrestrial record of East Antarctic Ice Sheet configuration and dynamics recorded by volcanic lithofacies and sequence characteristics in northern Victoria Land, Antarctica

    NASA Astrophysics Data System (ADS)

    Smellie, John; Rocchi, Sergio; Gemelli, Maurizio; di Vincenzo, Gianfranco; Armienti, Pietro

    2010-05-01

    Late Miocene (c. 12-5 Ma) volcanic sequences crop out extensively along > 250 km of northern Victoria Land coastline, at the Ross Sea margin of the East Antarctic Ice Sheet (EAIS). The sequences are dominantly glaciovolcanic and two main types are present. The commonest and most representative comprises multiple mafic aa lava-fed deltas, a type of glaciovolcanic sequence not previously described. The second sequence type resembles mafic glaciovolcanic sheet-like sequences of Mt Pinafore type (sensu Smellie, 2006, Earth-Science Reviews, 74, 241-268) but includes felsic examples as well, and there are additional minor occurrences of pyroclastic cones and an ice-marginal lacustrine deposit. Interpretation of the glaciovolcanic sequences enables estimates of past ice thicknesses that were coeval with eruptions to be made with considerable certainty. The sequences were formed in association with a glacial cover that was typically, and probably never much more than, a few hundred metres thick. Despite gaps in the record, no evidence was observed for subaerial (i.e. fully ice-free) eruptive conditions, suggesting either that ice-free conditions did not occur or else were of such short duration that they left no record. These observations are consistent with the presence of a late Miocene ice dome or regional ice sheet situated in northern Victoria Land for the period, although it may have been confluent with the EAIS similar to conditions present today. The basal glacial thermal regime varied from wet-based and dynamic, to cold-based (frozen to its bed) and presumably relatively stable. A major change from wet-based ice to cold-based ice is evident but its timing is not precisely determined. There is also evidence that temporary changes in thermal regime might have occurred before and after the principal transition.

  19. Ability of a land surface model to predict climate induced changes in northern Russian river runoff during the 21st century

    NASA Astrophysics Data System (ADS)

    Nasonova, O. N.; Gusev, Y. M.; Volodin, E. M.; Kovalev, E. E.

    2015-06-01

    The objective of the present study is application of the land surface model SWAP to project climate change impact on northern Russian river runoff up to 2100 using meteorological projections from the atmosphere-ocean global climate model INMCM4.0. The study was performed for the Northern Dvina River and the Kolyma River characterized by different climatic conditions. The ability of both models to reproduce the observed river runoff was investigated. To apply SWAP for hydrological projections, the robustness of the model was evaluated. The river runoff projections up to 2100 were calculated for two greenhouse gas emission scenarios: RCP8.5 and RCP4.5 prepared for the phase five of the Coupled Model Intercomparison Project (CMIP5). For each scenario, several runoff projections were obtained using different models (INMCM4.0 and SWAP) and different post-processing techniques for correcting biases in meteorological forcing data. Differences among the runoff projections obtained for the same emission scenario and the same period illustrate uncertainties resulted from application of different models and bias-correcting techniques.

  20. Wagering the land: Ritual, capital, and environmental degradation in the cordillera of Northern Luzon 1900-1986

    SciTech Connect

    Lewis, M.W.

    1992-01-01

    Tropical deforestation and land degradation in the Third World countries are topics that have moved to the academic center stage in the past 15 years. While this attention is long overdue, it is remarkable how little is understood of these processes. In addition, in the present rush to model global environmental change, the detail and place-specific nature of the expansion of agriculture and decline of forest cover may be ignored or overlooked. Wagering the Land is an important book because it forces one to confront the remarkably varied, complex, and site-specific causes of long-term environmental change. This book is strongly recommended to those engaged in the whole enterprise of modeling environmental change (particularly at the global level).

  1. Good for a national cemetery: questions of land use and an 1888 Botanical Expedition across Northern Michigan.

    PubMed

    Jones, Joseph J

    2009-01-01

    In the second half of the nineteenth century, lumbermen logged the virgin pine forests of northern Michigan. The assumption was that the "plow would follow the axe," and agriculture would dominate the region as it did in the southern half of the state. When farming did not quickly take root, William James Beal and Liberty Hyde Bailey led an expedition of scientists and journalists on a trip across northern Michigan in June 1888 to collect botanical samples, to find a site for a state forest reserve, and to recommend appropriate farming enterprises. This essay contends that without a key reforestation advocate in charles Garfield the explorers focused too much on the questions related to botany and agriculture.While agriculture would ultimately thrive in some parts of the cutover, much of the region was unsuitable for intensive farming. The failure of the scientists to convey these limits adequately in newspaper articles and subsequent reports allowed for their work to be used by agricultural boosters throughout the region. The result was a cycle of erosion, fire, and farm abandonment that proved to be a political problem in Michigan for the first three decades of the twentieth century. PMID:19728416

  2. Advanced interpretation of land subsidence by validating multi-interferometric SAR data: the case study of the Anthemountas basin (northern Greece)

    NASA Astrophysics Data System (ADS)

    Raspini, F.; Loupasakis, C.; Rozos, D.; Moretti, S.

    2013-04-01

    The potential of repeat-pass space borne SAR (Synthetic Aperture Radar) interferometry has been exploited to investigate spatial patterns of land subsidence in the Anthemountas basin, in the northern part of Greece. The PSI (Persistent Scatterer Interferometry) approach, based on the processing of long series of SAR acquisitions, has been applied to forty-two images acquired in 1995-2001 by ERS1/2 satellites. Interferometric results have been analyzed at a basin scale as support for land motion mapping and at local scale for the characterization of ground motion events affecting the village of Perea in the Thermaikos municipality and the "Macedonia" international airport. PSI results revealed a moderate subsidence phenomenon along the wider coastal zone of Anthemountas basin corresponding to intense groundwater extraction. Highest values, exceeding 20 mm yr-1, were measured in the airport area where the thickest sequence of compressible Quaternary sediments occurs. Intense subsidence has been detected also in the Perea village (maximum deformation up to 10-15 mm yr-1), where a series of fractures, causing damages to both buildings and infrastructure, occurred in 2005-2006. Furthermore, a linear pattern of deformation, elongated parallel to the major normal Thermi fault, has been observed, indicating movements with a probable tectonic component.

  3. Advanced interpretation of land subsidence by validating multi-interferometric SAR data: the case study of the Anthemountas basin (Northern Greece)

    NASA Astrophysics Data System (ADS)

    Raspini, F.; Loupasakis, C.; Rozos, D.; Moretti, S.

    2013-10-01

    The potential of repeat-pass space borne SAR (Synthetic Aperture Radar) interferometry has been exploited to investigate spatial patterns of land subsidence in the Anthemountas basin, in the northern part of Greece. The PSI (Persistent Scatterer Interferometry) approach, based on the processing of long series of SAR acquisitions, has been applied to forty-two images acquired in 1995-2001 by ERS1/2 satellites. Interferometric results have been analysed at a basin scale as support for land motion mapping and at a local scale for the characterisation of ground motion events affecting the village of Perea in the Thermaikos municipality and the "Macedonia" international airport. PSI results revealed a moderate subsidence phenomenon along the wider coastal zone of Anthemountas basin corresponding to intense groundwater extraction. Highest values, exceeding -20 mm yr-1, were measured in the airport area where the thickest sequence of compressible Quaternary sediments occurs. Intense subsidence has been detected also in the Perea village (maximum deformation of -10 to -15 mm yr-1), where a series of fractures, causing damages to both buildings and infrastructure, occurred in 2005-2006.

  4. Scientific rationale for selecting northern Eumenides Dorsum (9 deg - 11 deg N latitude, 159 deg - 162 deg longitude) as a potential Mars Pathfinder landing site

    NASA Technical Reports Server (NTRS)

    Parker, Tim J.

    1994-01-01

    The proposed site is the northernmost occurrence of the Medusae Fossae Formation (MFF), and lies at or below the -2 km contour. The MFF is the famous radar 'stealth' deposit that extends from south of Olympus Mons westward across southern Amazonis Planitia to southern Elysium Planitia. The MFF appears to be composed of some kind of wind-eroded friable material, the origin of which is very problematic. It appears to be a radar-absorbing material, whereas Mars' south polar layered deposits appear bright in the same scenes. Synthetic aperture radar images of young terrestrial ash deposits in the Andes also appear relatively bright. The MFF's radar signature appears to require a uniformly fine-grained material (on the order of dust-sized to fine sand-sized) at least several meters thick, in order not to transmit reflections off underlying terrain or internal reflective horizons. The proposed Pathfinder landing site lies on a relatively smooth, 'unmodified' portion of the MFF, more than 100 km away from its northern and western edges, which exhibit evidence of eolian etching in the form of closely spaced yardings. There are no large craters or steep slopes within a few hundred kilometers of the landing site.

  5. Effects of synoptic-scale circulation pattern and local land surface condition on fog at Kushiro, northern Japan

    NASA Astrophysics Data System (ADS)

    Sugimoto, S.; Sato, T.; Nakamura, K.

    2012-12-01

    Marine stratiform clouds are frequently observed over western North Pacific offshore of the northeast Japan during summer when warm southerly wind prevails over underlying cold ocean current. Such clouds often migrate over Kushiro located in the coastal area of eastern Hokkaido Island, north Japan and are recognized as sea fog. On the other hand, Kushiro is a middle-sized city with population of over 180,000 and a large wetland expands at the north of Kushiro city. The difference of land surface condition between the city and the wetland might cause heterogeneity of the sea fog distribution over land, via dissipation and regeneration process of fog. In this study, long-term visibility data for Kushiro are investigated to clarify the relationship between interannual variation of fog frequency (FF) and large-scale circulation patterns. Furthermore, frequency of fog/low-level cloud (LC) is identified using satellite images and sensitivity experiments changing land surface condition are conducted using meteorological regional model to understand an impact of land use on the local fog distribution and its physical processes. Monthly mean FF trends observed at Kushiro during 1931 to 2010 shows significant decline (-3.3 day per decade). Since late 1970s, the decline at Kushiro has been particularly remarkable in July and August in association with an increased number of years with very low FF. Analysis of radiosonde data has revealed the development of shallow moist layer under a strong inversion layer during fog occurrence because of abundant moisture supply from southerly wind. However, cold and dry northerly wind prevents the formation of inversion layer during fog-free days. Composite analysis of reanalysis data suggests that the low-level southerly wind toward northeast Japan is weaker in the low FF month of July than climatology owing to a southward shift of the North Pacific High (NPH) and stronger Okhotsk High. In August, eastward displacement or shrinking of the

  6. Land application of mine water causes minimal uranium loss offsite in the wet-dry tropics: Ranger Uranium Mine, Northern Territory, Australia.

    PubMed

    Mumtaz, Saqib; Streten, Claire; Parry, David L; McGuinness, Keith A; Lu, Ping; Gibb, Karen S

    2015-11-01

    Ranger Uranium Mine (RUM) is situated in the wet-dry tropics of Northern Australia. Land application (irrigation) of stockpile (ore and waste) runoff water to natural woodland on the mine lease is a key part of water management at the mine. Consequently, the soil in these Land Application Areas (LAAs) presents a range of uranium (U) and other metals concentrations. Knowledge of seasonal and temporal changes in soil U and physicochemical parameters at RUM LAAs is important to develop suitable management and rehabilitation strategies. Therefore, soil samples were collected from low, medium, high and very high U sites at RUM LAAs for two consecutive years and the effect of time and season on soil physicochemical parameters particularly U and other major solutes applied in irrigation water was measured. Concentrations of some of the solutes applied in the irrigation water such as sulphur (S), iron (Fe) and calcium (Ca) showed significant seasonal and temporal changes. Soil S, Fe and Ca concentration decreased from year 1 to year 2 and from dry to wet seasons during both years. Soil U followed the same pattern except that we recorded an increase in soil U concentrations at most of the RUM LAAs after year 2 wet season compared to year 2 dry season. Thus, these sites did not show a considerable decrease in soil U concentration from year 1 to year 2. Sites which contained elevated U after wet season 2 also had higher moisture content which suggests that pooling of U containing rainwater at these sites may be responsible for elevated U. Thus, U may be redistributed within RUM LAAs due to surface water movement. The study also suggested that a decrease in U concentrations in LAA soils at very high U (>900 mg kg(-1)) sites is most likely due to transport of particulate matter bound U by surface runoff and U may not be lost from the surface soil due to vertical movement through the soil profile. Uranium attached to particulate matter may reduce its potential for environmental

  7. Subsoil Carbon Stocks and Vulnerability to Land Use Change Across a Network of Seven Experimental Sites in the US Northern Lake States

    NASA Astrophysics Data System (ADS)

    Grand, S.; Rothstein, D.

    2015-12-01

    In this study, we report the depth distribution of soil organic carbon (SOC) and soil inorganic carbon (SIC) at experimental sites in the Northern Lake States (Michigan, Wisconsin and Minnesota) spanning a range of textural and geochemical environments. We also determined the vulnerability of SOC and SIC to the disturbance caused land-use change (conversion of old fields to short-rotation woody crop plantations). The experimental network consists of seven bioenergy plantations established in 2009-2010 in idled grass fields using herbicide and tillage. These study sites exhibit differences in soil texture (controlled largely by the type of glacial overlay) and geochemistry (controlled by the regional lithology including shale, basalt, limestone, sandstone and calcareous sandstone), providing the opportunity to gain insight into regional physical and chemical determinants of soil C storage. We conducted intensive soil sampling campaigns to a depth of 1 m prior to land conversion and at 4 years post-disturbance, to determine the depth profile and response of soil C storage as a function of land use and regional edaphic attributes. The proportion of subsoil SOC (stored at a depth greater than 25 cm) ranged from 33 to 50% of whole-profile SOC (to 1 m) prior to land conversion. Soils developed from calcareous parent materials also had significant SIC stocks despite the humid climate promoting carbonate weathering. The SIC stocks made up to half of the total soil C to a depth of 1 m. Measurable carbonates occurred throughout the profile, possibly due to upwards biological translocation mechanisms, but were most abundant at depths greater than 50 cm. Preliminary analyses indicate that SOC decreased in the topsoil following land-use change. These topsoil losses were offset by subsoil gains at sites with reactive mineralogy. The SIC stocks showed re-distribution following disturbance and were likely subject to accelerated weathering. Taken together, these results indicate

  8. Indigenous cosmology, art forms and past medicinal practices: towards an interpretation of ancient Koma Land sites in northern Ghana

    PubMed Central

    Kankpeyeng, Benjamin W.; Nkumbaan, Samuel N.; Insoll, Timothy

    2011-01-01

    The ancient cultural tradition in the middle belt region of northern Ghana, with its stone circle and house mounds, contains varied material culture. The unique contextual arrangements of the material culture within the stone circle mounds and the diverse ceramic art forms, as well as their ethnographic analogues in West Africa, indicate the mounds’ association with past shrines that have multiple functions, including curative purposes. The archaeology of the mounds and ethnographic associations related to past indigenous medical practices is reviewed and discussed. This paper will also consider how some of the figurines through which the Koma tradition has achieved ‘fame’ possibly functioned as physical representations of disease, perhaps underpinned by intentions of transference from afflicted to image. The notions of protection and healing are also examined with reference to the resorted and disarticulated human remains sometimes recovered from the sites. PMID:21810037

  9. Phreatophytic land-cover map of the northern and central Great Basin Ecoregion: California, Idaho, Nevada, Utah, Oregon, and Wyoming

    USGS Publications Warehouse

    Mathie, Amy M.; Welborn, Toby L.; Susong, David D.; Tumbusch, Mary L.

    2011-01-01

    Increasing water use and changing climate in the Great Basin of the western United States are likely affecting the distribution of phreatophytic vegetation in the region. Phreatophytic plant communities that depend on groundwater are susceptible to natural and anthropogenic changes to hydrologic flow systems. The purpose of this report is to document the methods used to create the accompanying map that delineates areas of the Great Basin that have the greatest potential to support phreatophytic vegetation. Several data sets were used to develop the data displayed on the map, including Shrub Map (a land-cover data set derived from the Regional Gap Analysis Program) and Gap Analysis Program (GAP) data sets for California and Wyoming. In addition, the analysis used the surface landforms from the U.S. Geological Survey (USGS) Global Ecosystems Mapping Project data to delineate regions of the study area based on topographic relief that are most favorable to support phreatophytic vegetation. Using spatial analysis techniques in a GIS, phreatophytic vegetation classes identified within Shrub Map and GAP were selected and compared to the spatial distribution of selected landforms in the study area to delineate areas of phreatophyte vegetation. Results were compared to more detailed studies conducted in selected areas. A general qualitative description of the data and the limitations of the base data determined that these results provide a regional overview but are not intended for localized studies or as a substitute for detailed field analysis. The map is intended as a decision-support aide for land managers to better understand, anticipate, and respond to ecosystem changes in the Great Basin.

  10. Numerical model to evaluate the mitigation strategies to combat desertification and drought in the arid land of northern Chile.

    NASA Astrophysics Data System (ADS)

    Salinas, Carla; Mendieta, Jon

    2014-05-01

    Desertification is considered a global environmental problem with political and socioeconomic implications. Desertification, exacerbated by climate change, is the largest environmental problem in Chile affecting almost two third of the national territory. This study takes place in a latitudinal gradient of the north-central Chilean drylands, where desertification is a threat to agriculture, livestock and forestry (ALF). The critical areas or priority areas for combating desertification are the northernmost areas of the region under study. In the context of the United Nations Convention to Combat Desertification (UNCCD) and the implementation of the Chilean National Action Programme (NAP), the country is conducting policies and investing in mitigation strategies to combat land degradation and desertification. The main objective of this study is the development of an integrative methodological approach using real data of the territorial and socioeconomic indicators. With the proposed methodology we assess the impact of the mitigation and land degradation strategies supported by the ALF promotion agencies in the fight against desertification, projecting different scenarios of change. The data were collected in 2008 in Santiago, Chile. The results of the Principal Component Analysis (PCA) suggest that technical irrigation and the improvement of grasslands and pastures play an important role in the fight against desertification. The results of the model projections are consistent, suggesting that the efforts of the ALF promotion agencies have a positive impact in fighting desertification. Inaction of ALF mitigation strategies would increase desertification. This methodological approach, performed with real data, can also determine the main causes of desertification in such a complex area as the studied one, where we can find the desert itself, and its desertification endangered valleys, the Andean plateau, the transitional area and the southern regions. Ii is also a

  11. The thickness history of the northern sector of the Laurentide Ice Sheet: an assessment of glacial isostatic adjustment models, sea-level measurements, and vertical land motion rates

    NASA Astrophysics Data System (ADS)

    Simon, K. M.; James, T. S.; Henton, J. A.; Dyke, A.

    2014-12-01

    The fit of glacial isostatic adjustment (GIA) model predictions to 24 relative sea-level histories and an additional 18 present-day GPS-measured vertical land motion rates constrains the thickness and volume history of the central and northern Laurentide Ice Sheet. The predictions of the best-fit GIA model indicate respective peak ice thicknesses west and east of Hudson Bay of 3.4-3.6 km and approximately 4 km. These values represent, respectively, a large decrease, and a moderate increase, to the load thickness compared to ICE-5G. This result is generally consistent with other GIA studies focussing on space-geodetic constraints. The large reduction to the ice load west of Hudson Bay also reduces the vertical mantle response along the margins of the load centre, which improves the fit to relative sea-level data from the southern Canadian Arctic Archipelago. The fit of GIA model predictions to relative sea-level data from the Baffin Sector of the Laurentide Ice Sheet indicate peak ice thicknesses there of 1.2-1.3 km, a modest reduction compared to ICE-5G. On Baffin Island, the modelled elastic crustal response of the Earth to present-day ice mass changes is large. Accounting for this effect improves the agreement between GPS measurements of vertical crustal motion and the GIA model predictions. However, work is needed to incorporate more detailed observations and modelling of present-day changes to glaciers and ice caps. Overall, the fit to the data is most strongly improved in the region west of Hudson Bay (the χ2 RSL misfit is reduced by a factor of ~4) although the entire revised reconstruction for the central and northern Laurentide Ice Sheet provides an improved fit to both the regional RSL data (the cumulative χ2 misfit is reduced by a factor of >2) and the GPS data (the RMS misfit is reduced by a factor of 9).

  12. Spatial distribution and temporal variation of ecological capital and their relation to climate change and the changes of land use and land cover on the northern slope of the Tianshan Mountain, China

    NASA Astrophysics Data System (ADS)

    Zhang, Qing; Chen, Xiuwan; Gao, Wei; Zhang, Xianfeng; Zhou, Kefa; Wang, Xinli

    2007-09-01

    Ecological capital of an ecosystem is the total value of the direct biological products in the system and the value of ecological service. The assessment of ecological capital is a new research area emerged from the challenge in the interdisciplinary research of ecology and social development. It is fundamental to establish a green national economy accounting system. Scientific evaluation of ecological capital is helpful for considering ecological cost in making the decision for economic development, and it is demanded for sustainable development. In this study, a quantitative assessment model of ecological property has been developed based on the analysis of per unit yield in the conventional ecology together with the utilization of remote sensing data from the Landsat TM, CBERS, MODIS, and NOAA database, land use and land cover data, and field measurements. The study area covers Changji Autonomous District, Xinjiang, China on the northern slope of Tianshan Mountain that is located in a typical arid area. Dynamic monitoring of ecological capital was performed using remote sensing techniques. Spatial distribution and temporal variation of ecological properties were characterized. The effects of land cover and land use as well as climate change on those variation and distribution were analyzed. The results show a significant increase in the ecological capital during 1990-2003. The spatial distribution of ecological properties is characterized by a negative gradient from higher altitudes to lower altitudes (plains) and from oases to deserts, which is consistent with the zonal distribution of vegetation in arid areas. Due to global warming, the climate in Xinjiang has been changed into a warmer and wetter environment during the last 50 years, which improves the plant growing conditions in the alpine regions, piedmont hilly regions, and the oases. On the other hand, the natural environment in the arid and semiarid regions in northwest China becomes more severe, and the

  13. Reversing land degradation in the densely populated and semi-arid highlands of Tigray (Northern Ethiopia) - evidence from photomonitoring with 30 years interval

    NASA Astrophysics Data System (ADS)

    Nyssen, J.; Munro, R. N.; Poesen, J.; Deckers, J.; Haile, M.; Grove, A. D.

    2007-12-01

    Studies on the impact of environmental rehabilitation in semi-arid areas are often limited in scale, and do typically not include detailed bio-physical components (Rohde and Hilhorst, 2001). As a first in its kind, the present study makes a multi-scale assessment over a time span of 30 years of environmental rehabilitation in one of the world's most degraded areas: the Tigray highlands in Northern Ethiopia, where population has more than doubled over that period. Using methods related to geomorphology, hydrology, soil science and multi-temporal photomonitoring (Nyssen et al., 2007), we show that in Tigray, soil erosion rates have decreased, infiltration and spring discharge are enhanced, vegetation cover has increased and crop production improved compared to the prevailing situation a few decades ago. These impacts are quantified and substantiated by a comparison of current landscapes to the past situation by means of a comprehensive database of 30-year old photographs of representative landscapes covering the major agro-ecological zones of the region. This resilience will be discussed in the light of the socio-economic context in which it has taken place. Finally, the positive changes in ecosystem service supply that result from changing land cover and management are an issue of global concern. Our research demonstrates that the way is open to develop down-to-the-ground environmental indicators to gauge 'Millennium Ecosystem Assessment' type approaches (Carpenter et al., 2006). Carpenter, S.R., DeFries, R., Dietz, T., Mooney, H.A., Polasky, S., Reid, W.V., Scholes, R.J., 2006. Millennium Ecosystem Assessment: research needs. Science 314: 257-258. Nyssen, J., Poesen, J., Descheemaeker, K., Nigussie Haregeweyn, Mitiku Haile, Moeyersons, J., Govers, G., Munro, R.N., Deckers, J., 2007. Reversing land degradation in marginal semi-arid areas: the case of Northern Ethiopia. Ecosystems, submitted. Rohde, R., Hilhorst, T., 2001. A profile of environmental change in the

  14. Analysis of land use changes over the last 200 years in the catchment of Lake Czechowskie (Pomerania, northern Poland)

    NASA Astrophysics Data System (ADS)

    Tyszkowski, Sebastian; Kaczmarek, Halina

    2014-05-01

    Changes in land cover in the catchment area are, beside climate change, some of the major factors affecting sedimentation processes in lakes. With increasing human impact, changes in land cover no longer depend primarily on climate. In relation to research on sediments of Lake Czechowskie in Pomeranian Province in North Poland, land use changes over the last 200 years were analysed, with particular reference to deforestation or afforestation. The study area was the lake catchment, which covers nearly 20 km2. The analysis was based on archival and contemporary cartographic and photogrammetric materials, georeferenced and rectified using ArcGIS software. The following materials were used: Schrötter-Engelhart, Karte von Ost-Preussen nebst Preussisch Litthauen und West-Preussen nebst dem Netzdistrict, 1:50 000, section 92, 93, 1796-1802; Map Messtishchblatt, 1:25000, sheet Czarnen, (mapping conducted in 1874), 1932; Map WIG (Military Geographical Institute - Wojskowy Instytut Geograficzny), 1:25000, sheet Osowo, (mapping conducted in 1929-31), 1933; aerial photos 1:13000, 1964, 1969; 1:25000, 1987; 1:26000, 1997; aerial ortophotomap , 1:5000, 2010. Today, over 60% of the catchment of Lake Czechowskie is covered with forests, dominated by planted Scots pine (Pinus sylvestris), while the remaining areas are used for agricultural purposes or are built up. The first cartographic materials indicate that in the late 18th c., forest covered almost 50% of the catchment surface. By the year 1870, there was a significant reduction in the forested area, as its contribution fell to 40%. Deforestation took place mainly between the main villages. In the 1920s the forest cover increased to 44%. Today, almost the entire lake is surrounded by forest and a wetland belt (at least 0.5 km wide). Deforestation in the catchment should not be attributed solely to logging because the area of Tuchola Forests (Bory Tucholskie) was repeatedly affected by natural disasters. In the 19th c. these

  15. Conservation of northern bobwhite on private lands in Georgia, USA under uncertainty about landscape-level habitat effects

    USGS Publications Warehouse

    Howell, J.E.; Moore, C.T.; Conroy, M.J.; Hamrick, R.G.; Cooper, R.J.; Thackston, R.E.; Carroll, J.P.

    2009-01-01

    Large-scale habitat enhancement programs for birds are becoming more widespread, however, most lack monitoring to resolve uncertainties and enhance program impact over time. Georgia?s Bobwhite Quail Initiative (BQI) is a competitive, proposal-based system that provides incentives to landowners to establish habitat for northern bobwhites (Colinus virginianus). Using data from monitoring conducted in the program?s first years (1999?2001), we developed alternative hierarchical models to predict bobwhite abundance in response to program habitat modifications on local and regional scales. Effects of habitat and habitat management on bobwhite population response varied among geographical scales, but high measurement variability rendered the specific nature of these scaled effects equivocal. Under some models, BQI had positive impact at both local farm scales (1, 9 km2), particularly when practice acres were clustered, whereas other credible models indicated that bird response did not depend on spatial arrangement of practices. Thus, uncertainty about landscape-level effects of management presents a challenge to program managers who must decide which proposals to accept. We demonstrate that optimal selection decisions can be made despite this uncertainty and that uncertainty can be reduced over time, with consequent improvement in management efficacy. However, such an adaptive approach to BQI program implementation would require the reestablishment of monitoring of bobwhite abundance, an effort for which funding was discontinued in 2002. For landscape-level conservation programs generally, our approach demonstrates the value in assessing multiple scales of impact of habitat modification programs, and it reveals the utility of addressing management uncertainty through multiple decision models and system monitoring.

  16. Seasonality of Air-sea-ice-land Variables for Arctic Tundra in Northern Eurasia and North America

    NASA Astrophysics Data System (ADS)

    Bhatt, U. S.; Walker, D. A.; Raynolds, M. K.; Steele, M.; Epstein, H.; Jia, G.; Comiso, J. C.; Pinzon, J. E.; Tucker, C. J.

    2009-12-01

    The strength of tundra productivity trends as measured by the annual maximum Normalized Difference Vegetation Index (MaxNDVI) and time integrated NDVI (TI-NDVI) vary around the Arctic over the 1982-2008 period. Our analysis suggests that the timing of terrestrial vegetation growth is connected to seasonal patterns of sea-ice concentrations, ocean temperatures and land surface temperatures. This study used SSMI estimates of sea ice concentration, based on a bootstrap algorithm and AVHRR radiometric surface temperature. Summer Warmth Index (SWI) was calculated as the sum from May to August of the degree months above freezing of surface temperature at each pixel and is an accepted measure of plant growth potential. The Normalized Difference Vegetation Index (NDVI) represents vegetation greenness and has been used extensively to monitor changes in the Arctic. The albedo of green plants varies with solar radiation wavelength, which is the basis for the NDVI index. The analysis was conducted within 50 km of the Arctic coastline to focus on the region of maximum maritime influence. Time series of regional sea-ice concentration, SWI and NDVI were constructed for the 50-km width domains for the Pan-Arctic, North America, Eurasia and Arctic subregions. Standard climate analysis techniques were applied to the regional time series to investigate the seasonality of sea ice, NDVI and SWI. MaxNDVI has increased in the 50-km land domain contiguous to the Beaufort Sea by 17% since 1982, whereas it has only increased by 3% in the coastal Kara Sea region. Analysis of semimonthly MaxNDVI indicates that the vegetation greens up more rapidly in the spring in the Beaufort than the W. Kara and the Kara has slightly higher NDVI in the fall. The climatological weekly sea ice concentrations in 50-km coastal domain displays an earlier breakup in the Beaufort and a later freeze-up in the Kara Sea area. Regional differences in the seasonal cycle can in part explain the spatially varied trends

  17. The role of plant-soil feedbacks and land-use legacies in restoration of a temperate steppe in northern China

    SciTech Connect

    Jiang, Lili; Han, Xingguo; Zhang, Guangming; Kardol, Paul

    2010-11-01

    Plant soil feedbacks affect plant performance and plant community dynamics; however, little is known about their role in ecological restoration. Here, we studied plant soil feedbacks in restoration of steppe vegetation after agricultural disturbance in northern China. First, we analyzed abiotic and biotic soil properties under mono-dominant plant patches in an old-field restoration site and in a target steppe site. Second, we tested plant soil feedbacks by growing plant species from these two sites on soils from con- and heterospecific origin. Soil properties generally did not differ between the old-field site and steppe site, but there were significant differences among mono-dominant plant patches within the sites. While soil species origin (i.e., the plant species beneath which the soil was collected) affected biomass of individual plant species in the feedback experiment, species-level plant soil feedbacks were neutral . Soil site origin (old-field, steppe) significantly affected biomass of old-field and steppe species. For example, old-field species had higher biomass in old-field soils than in steppe soils, indicating a positive land-use legacy. However, soil site origin effects depended on the plant species beneath which the soils were collected. The predictive value of abiotic and biotic soil properties in explaining plant biomass differed between and within groups of old-field and steppe species. We conclude that the occurrence of positive land-use legacies for old-field species may retard successional replacement of old-field species by steppe species. However, high levels of idiosyncrasy in responses of old-field and steppe plant species to con- and heterospecific soils indicate interspecific variation in the extent to which soil legacies and plant soil feedbacks control successional species replacements in Chinese steppe ecosystems.

  18. Land use and climate affect Black Tern, Northern Harrier, and Marsh Wren abundance in the Prairie Pothole Region of the United States

    USGS Publications Warehouse

    Forcey, Greg M.; Thogmartin, Wayne E.; Linz, George M.; McKann, Patrick C.

    2014-01-01

    Bird populations are influenced by many environmental factors at both large and small scales. Our study evaluated the influences of regional climate and land-use variables on the Northern Harrier (Circus cyaneus), Black Tern (Childonias niger), and Marsh Wren (Cistothorus palustris) in the prairie potholes of the upper Midwest of the United States. These species were chosen because their diverse habitat preference represent the spectrum of habitat conditions present in the Prairie Potholes, ranging from open prairies to dense cattail marshes. We evaluated land-use covariates at three logarithmic spatial scales (1,000 ha, 10,000 ha, and 100,000 ha) and constructed models a priori using information from published habitat associations and climatic influences. The strongest influences on the abundance of each of the three species were the percentage of wetland area across all three spatial scales and precipitation in the year preceding that when bird surveys were conducted. Even among scales ranging over three orders of magnitude the influence of spatial scale was small, as models with the same variables expressed at different scales were often in the best model subset. Examination of the effects of large-scale environmental variables on wetland birds elucidated relationships overlooked in many smaller-scale studies, such as the influences of climate and habitat variables at landscape scales. Given the spatial variation in the abundance of our focal species within the prairie potholes, our model predictions are especially useful for targeting locations, such as northeastern South Dakota and central North Dakota, where management and conservation efforts would be optimally beneficial. This modeling approach can also be applied to other species and geographic areas to focus landscape conservation efforts and subsequent small-scale studies, especially in constrained economic climates.

  19. Assimilating MODIS Snow Covers into Land Surface Model: Validation with in-situ Snow Measurements in Northern Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Huang, Chunlin; Hou, Jinliang; Wang, WeiZhen

    2016-04-01

    Accurate monitoring of the spatiotemporal distribution and variation of snow cover is important for snowmelt runoff simulation and water resources management especially in mountainous areas. In this work, we develop a snow data assimilation scheme based on Ensemble Kalman Filter (EnKF) algorithm and Common Land Model (CoLM), which can assimilate snow cover fraction (SCF) products from the Moderate resolution imaging Spectroradiometer (MODIS) into CoLM for improving snow depth (SD) and snow cover area simulations. An empirical model between SD and SCF has been built based on MODIS SCF and snow depth observations at meteorological stations located in study area, which is used as observation operator in snow data assimilation scheme. The assimilation experiment is conducted during 2004-2007, in Xingjiang province, west China. The preliminary assimilation results are very promising and show that the assimilation of SCF could significantly improve the CoLM capability of simulating snow cover area and snow depth. The assimilation results are more closer to those of observations, which have more reasonable and reliable snow accumulation and melting trends throughout the snow season. After assimilating MODIS SCF observations, the Root Mean Square Error (RMSE) and Mean Bias error (MBE) of snow cover or snow depth are significantly reduced compared to the results without assimilation.

  20. Determining the sensitivity of the high mountain region in Northern Romania to climate and land use changes through multi-proxy analysis

    NASA Astrophysics Data System (ADS)

    Feurdean, Angelica; Geanta, Anca; Tantau, Ioan; Auer, Andreea; Hutchinson, Simon

    2013-04-01

    Climate and land use changes can have a great impact on high altitude environments due to their species' narrow tolerance capabilities, habitat fragmentation and habitat restriction. Since trees at the timberline and the treeline ecotone grow at their temperature and soil tolerance limit, even small alterations in these parameters can result in marked changes in the position of the treeline ecotone, diversity, and species composition. Current and future climate warming is anticipated to shift the tree and timberlines upwards, whereas land use changes can drive this movement in the opposite direction. Therefore the long-term responses of vegetation to past climate variations and land use changes are of particular relevance for the prediction of future vegetation change in high mountain areas. Here, we use a multi-proxy analysis (pollen, spores, micro and macrocharcoal, mineral magnetic properties and AMS 14C dating) of a 1m lacustrine sequence covering the last 5000 years located in the subalpine zone (1910 m a.s.l.) in the Rodna Mountains (Northern Romanian Carpathians) to determine the sensitivity of high mountain habitats (i.e., movements of the timberline and treeline ecotones, and changes in vegetation composition diversity) in response to climate, fires and land use. The pollen and stomata records reveal regional forests dominated by Pinus sylvestris between ca. 5000 and 4250 cal yrs BP, which were replaced by Picea abies, Abies alba and Fagus sylvatica from about 4200 cal yrs BP onwards. The proximity of the lake was treeless, dominated by sub-alpine shrubs (Alnus viridis), alpine herbaceous communities (Poaceae, Cyperaceae, Apiaceae, Asteraceae Tubuliflorae, A. Liguliflorae, Thalictrum) and ruderal species (Artemisia, Rumex, Chenopodiaceae) through almost the whole record. However, Pinus stomata found between 5000 and 4000 cal yr BP probably indicate a higher position of the treeline and the local occurrence of Pinus before 4000 cal yr BP. Our results show

  1. Impact of conservation agriculture on harnessing sustainability and building resilience against land degradation in the northern Ethiopian highlands

    NASA Astrophysics Data System (ADS)

    Araya, Tesfay; Cornelis, Wim M.; Govaerts, Bram; Bauer, Hans; Deckers, Jozef; Nyssen, Jan

    2013-04-01

    Conservation Agriculture (CA) aims at improving soil quality and crop yield whilst reducing runoff and topsoil erosion which raises the soil resilience to combat soil degradation. Different chemical, physical, and biological properties of a soil interact in complex ways that determine the crop productivity potential of the soil. Hence, a medium-term tillage experiment was carried out (2005 to 2011) on a Vertisol to evaluate changes in soil quality, runoff and soil loss due to CA-based field conservation practices in northern Ethiopia. The experimental layout was implemented in a randomized complete block design with three replications on permanent plots of 5 m by 19 m. The tillage treatments were derdero+ (DER+) with a furrow and permanent raised bed planting system, plowed once at planting by refreshing the furrow and with 30% standing crop residue retention, terwah+ (TER+) with plowing once at planting with 30% standing crop residue retention and contour furrows made at 1.5 m distance interval, and conventional tillage (CT) with a minimum of three tillage operations and removal of crop residues. All the plowing and reshaping of the furrows was done using the local ard plow mahresha. Local crop rotation practices followed during the seven years sequentially from the first to the seventh year included wheat-teff-wheat-barley-wheat-teff-grass pea. Glyphosate was sprayed starting from the third year (2007) at 2 l ha-1 before planting to control pre-emergent weed in DER+ and TER+. Significantly different (p<0.05) mean runoff coefficients (%) in 7-yrs of 13, 20 and 27 were recorded for DER+, TER+ and CT, respectively. Mean soil losses of 7-yrs were 4.4, 12.5 and 18 t ha-1 y-1 in DER+, TER+ and CT, respectively. Among the several assessed soil properties, SOM, N, P, soil microbial biomass carbon, aggregate stability index, consistency index, cone index, air capacity and macroporosity were shown to significantly increase in soils subjected to DER+ planting system

  2. Argon-40/argon-39 whole-rock slate ages from the Robertson Bay terrane, northern Victoria Land: Documenting diachronous orogeny as a result of terrane accretion

    SciTech Connect

    Dallmeyer, R.D.

    1987-09-01

    In models of tectonic convergence, oceanic material enters subduction zones, descends, and is deformed. Over time subduction cuts across areas of deformation and should become younger in a direction opposite the dip of the subduction zone. Typically, geologists have found it difficult to document this because of insufficient cross-strike exposure, uncertainties in interpretation of radiometric ages, and overprinting of later tectonothermal events. The Robertson Bay and Bowers terranes of northern Victoria Land, which were accreted to the east antarctic craton (Gondwana margin) during the Ordovician Ross Orogeny, offer a unique opportunity to document a potentially diachronous deformation associated with an Ordovician orogeny. Exposed over a large area, these terranes display nearly uniform lithology, low metamorphic grade, and structural style and are combined with the absence of a regionally significant tectonothermal over print. Reconnaissance age analysis by potassium/argon and argon-40/argon-39 methods suggests that ages decrease eastward across the Robertson Bay terrane. The objective is systematically to collect samples of and perform argon-40/argon-39 age analysis on a whole-rock suite from the Bowers and Robertson Bay terranes. The resultant ages would more clearly document the suggested diachronism and allow more rigorous evaluation of the various tectonothermal models proposed for the evolution of the Gondwana margin.

  3. Sensitivity Analysis and Investigation of the Behaviour of the UTOPIA Land-Surface Process Model: A Case Study for Vineyards in Northern Italy

    NASA Astrophysics Data System (ADS)

    Francone, C.; Cassardo, C.; Richiardone, R.; Confalonieri, R.

    2012-09-01

    We used sensitivity-analysis techniques to investigate the behaviour of the land-surface model UTOPIA while simulating the micrometeorology of a typical northern Italy vineyard ( Vitis vinifera L.) under average climatic conditions. Sensitivity-analysis experiments were performed by sampling the vegetation parameter hyperspace using the Morris method and quantifying the parameter relevance across a wide range of soil conditions. This method was used since it proved its suitability for models with high computational time or with a large number of parameters, in a variety of studies performed on different types of biophysical models. The impact of input variability was estimated on reference model variables selected among energy (e.g. net radiation, sensible and latent heat fluxes) and hydrological (e.g. soil moisture, surface runoff, drainage) budget components. Maximum vegetation cover and maximum leaf area index were ranked as the most relevant parameters, with sensitivity indices exceeding the remaining parameters by about one order of magnitude. Soil variability had a high impact on the relevance of most of the vegetation parameters: coefficients of variation calculated on the sensitivity indices estimated for the different soils often exceeded 100 %. The only exceptions were represented by maximum vegetation cover and maximum leaf area index, which showed a low variability in sensitivity indices while changing soil type, and confirmed their key role in affecting model results.

  4. Application of OMI tropospheric NO2 for air quality monitoring in Northern Europe: shipping and land-based case studies

    NASA Astrophysics Data System (ADS)

    Ialongo, Iolanda; Hakkarainen, Janne; Jalkanen, Jukka-Pekka; Johansson, Lasse; Boersma, Folkert; Krotkov, Nickolay; Tamminen, Johanna

    2014-05-01

    Satellite-based data are very important for air quality applications in the Baltic Sea area, because they provide information on air pollution over sea and there where ground-based network and aircraft measurements are not available. Both the emissions from urban sites over land and ships over sea, contribute to the tropospheric NO2 levels. The tropospheric NO2 monitoring at high latitudes using satellite data is challenging because of the reduced light hours in winter and the snow-covered surface, which make the retrieval complex, and because of the reduced signal due to low Sun. This work presents a detailed characterization of the tropospheric NO2 columns focused on part of the Baltic Sea region using the Ozone Monitoring Instrument (OMI) tropospheric NO2 standard product. Previous works have focused on larger seas and lower latitudes. The results showed that, despite the regional area of interest, it is possible to distinguish the signal from the main coastal cities and from the ships by averaging the data over a seasonal time range. The summertime NO2 emission and lifetime values (E = (1.0 ± 0.1)x1028 molec. and τ = (3.0 ± 0.5) h, respectively) in Helsinki were estimated from the decay of the signal with distance from the city center. The method developed for megacities was successfully applied to a smaller scale source, in both size and intensity (i.e., the city of Helsinki), which is located at high latitudes (~ 60oN). The same methodology could be applied to similar scale cities elsewhere, as far as they are relatively isolated from other sources. The transport by the wind plays an important role in the Baltic Sea area. The NO2 spatial distribution is mainly determined by the contribution of strong westerly winds, which dominate the wind patterns during summer. The comparison between the emissions from model calculations and OMI NO2 tropospheric columns confirmed the applicability of satellite data for ship emission monitoring. In particular, both the

  5. Land cover and future climate effects on the provision of hydrological services: SWAT applied to a medium-sized watershed of northern Portugal

    NASA Astrophysics Data System (ADS)

    Carvalho-Santos, Claudia; Nunes, João Pedro; Monteiro, António T.; Hein, Lars; Honrado, João

    2015-04-01

    Land cover change and future climate conditions may influence the provision of hydrological services. Therefore, it is important to understand how these drivers will affect water supplies and water hazards mitigation, in order to support the planning and management of water resources. In this study, the separated and combined effects of land cover and future climate on the hydrology of the Vez watershed, northern Portugal, were evaluated. The Vez watershed (252 Km2) has a humid climate regime where precipitation is abundant all over the year (1500mm/yr), with exception of a summer with almost no rain. The SWAT (Soil and Water Assessment Tool) model was calibrated against daily discharge, sediments and nitrates, with good agreements between model predictions and field observations related with discharge; the calibration of sediments and nitrates can be considered adequate given the limitations of observed data. Four hypothetical land cover scenarios were applied under current climate conditions (eucalyptus/pine, oak, agriculture/vine and low vegetation). Results for land cover revealed that the option for one particular scenario would not compromise the overall provision of hydrological services. However, the eucalyptus/pine scenario could reduce the annual water quantity by 7%, and up to 17% in the summer period; and the agriculture/vine scenario could increase soil erosion and nitrate exports. For the future climate scenario, a statistical downscaling of four ensemble GCMs (General Circulation Models), bias-corrected with ground observations was done for 2021-40 and 2041-60, using the RCP 4.5 medium emissions scenario. An increase in temperature (annual: 1.6°C; summer: 2.02°C) and a decrease in precipitation (annual: -3.9%), more pronounced in summer (-25%) are expected in the Vez watershed. Although climate change has only a modest effect in the reduction of the total annual discharge (-7%), the effect on streamflow during summer can be more pronounced (between

  6. The Role of Deforestation in the Collapse of Classic Maya Civilization: Lessons for the Current Land Use Management in Northern Mesoamerica

    NASA Astrophysics Data System (ADS)

    Ray, D. K.; Nair, U. S.; Welch, R. M.; Lawton, R. O.; Oglesby, R. J.; Pielke, R. A.; Sever, T. A.; Irwin, D.

    2005-12-01

    143.3mm compared to 142.7 mm for current conditions (a negligible decrease of 0.4% over the forested scenario). However, domain averaged dry season rainfall in the Maya lowlands decreases to 128.9mm for the deforested scenario, a decrease in 9.7% over current conditions. The model simulations suggest that to-date deforestation has played an insignificant role in creating drier conditions in the Mayan lowlands, except in the regions in northern Guatemala and adjacent Mexico. However, continued deforestation that would be representative of those prior to the collapse of the Maya civilization in the region can be expected to lead to additional decreases in dry season precipitation throughout the entire region by about 10mm to 100mm. Improper land use management in this region could lead to futures catastrophes for the modern humans similar

  7. Oxo-amphiboles in mantle xenoliths: evidence for H2O-rich melt interacting with the lithospheric mantle of Harrow Peaks (Northern Victoria Land, Antarctica)

    NASA Astrophysics Data System (ADS)

    Gentili, S.; Bonadiman, C.; Biagioni, C.; Comodi, P.; Coltorti, M.; Zucchini, A.; Ottolini, L.

    2015-12-01

    Amphiboles are the most widespread hydrous metasomatic phases in spinel-bearing mantle peridotites from Harrow Peaks (HP), Northern Victoria Land (Antarctica). They occur both in veinlets and disseminated in the peridotite matrix (preferentially associated with clinopyroxene and spinel grains). Four amphibole crystals were investigated by single-crystal X-ray diffraction (SC-XRD), electron microprobe analysis (EMPA), secondary ion mass spectrometry (SIMS) and micro-Mössbauer spectroscopy; these crystal-chemical data allow to constrain upper mantle conditions during growth of these amphiboles and the role of volatile circulation during metasomatic processes in the Antarctic region. The HP amphiboles have low Mg# values (69.3-84.1), high TiO2 (2.74-5.30 wt%) and FeOtot contents (3.40 to 6.90 wt%). The Fe3+/Fetot ratios are significantly high (0.53-0.66). The W-site is mainly occupied by O2- (0.984-1.187 apfu) plus OH (H2O: 0.70-1.01 wt%) and minor F (0.04-0.24 wt%) and Cl (0.03-0.08 wt%). Consequently, HP amphiboles are actually characterized by a significant oxo component. The aH2O values were calculated at 1.5 GPa by dehydration equilibrium equations written as H2O-buffering equilibria among end-member components of amphibole and coexisting peridotite phases. Three out of four HP amphibole-bearing peridotites have values of aH2O ranging from 0.122 to 0.335; whereas one sample has aH2O remarkably higher (0.782) approaching an ideal H2O basalt solubility. The HP fO2 values, determined by the olivine-spinel-orthopyroxene oxygeobarometer (ΔQFM = -1.77 : +0.01), are remarkably different from those calculated on the basis of the amphibole dehydration equilibrium and the application of the dissociation reaction (ΔQFM = -2.60 : +6.8). The high aH2O and the extremely high fO2 values, determined by the oxy-amphibole equilibrium with respect to the redox conditions recorded by the co-existing anhydrous minerals (close to QFM buffer), revealed that: i) the amphibole

  8. Volatile content in MI from Petrological study of basic lavas and melt inclusions from Cenozoic volcanism from Northern Victoria Land (Antarctica)

    NASA Astrophysics Data System (ADS)

    Giacomoni, Pier Paolo; Coltorti, Massimo; Mukasa, Sam; Bonadiman, Costanza; Ferlito, Carmelo

    2014-05-01

    New data on basic lavas and melt inclusions (MI) in olivine phenocrysts from Northern Victoria Land (NVL-Antarctica) are presented aiming at comparing major element composition and volatiles content in lavas and their mantle sources. Major elements and volatile (H2O, CO2, S, F and Cl) were measured in MI from Shield Nunatak, while major and trace elements were carried out on lavas from three localities, Eldridge Bluff, Shield Nunatak and Handler Ridge. Lavas are olivine-phyric (up to 15 %vol) with minor clinopyroxene and plagioclase in a glassy to microcristalline plagioclase-dominated groundmass; opaque minerals are mostly magnetites and subordinately ilmenites. The great majority of lavas are basanites (42.20-45.02wt% SiO2, with 3.36-4.21wt% of Na2O+K2O) with Mg# (MgO/(MgO+FeO) mol%, Fe2O3=0.15FeO) ranging from 44.9 to 60.1. Lavas from Handler Ridge are the most primitive. MI compositions are comparable to those of the host lavas but encompasse a wider range from 43.68 to 48.73 wt% SiO2 and from 2.81 to 4.55 wt% Na2O+K2O, with Mg# 49.5 74.44. The great majority of olivine calculated in equilibrium with MI are more forsteritic than the enclosing crystal suggesting that MI were trapped from a less evolved magma or, most probaby, that Mg-Fe interdiffusion occurred between olivine and MI after entrapment. Most of MI have H2O content ranging from 0.70 wt% to 1.19 wt% and CO2 from 25 ppm to 341 ppm (H2O/CO2~1). At comparable H2O contents few samples show a remarkable higher CO2 values (1322 ppm to 3905 ppm) with a H2O/CO2 down to 0.8. F and Cl concentrations range from 808 to 999 ppm and from 443 to 570 ppm respectively, with a F/Cl ratio ranging between 1.4 to 2.0. S content varies from 537 ppm to 2002 ppm. The relationships between MI and basic lava compositions are investigated by means of mass balance calculation reconstructing the composition of the mantle source, including amphibole from Baker Rocks (NVL) which allow us to also constrain its volatile content

  9. The Classical Assumption Test to Driving Factors of Land Cover Change in the Development Region of Northern Part of West Java

    NASA Astrophysics Data System (ADS)

    Ainiyah, Nur; Deliar, Albertus; Virtriana, Riantini

    2016-06-01

    Land cover changes continuously change by the time. Many kind of phenomena is a simple of important factors that affect the environment change, both locally and also globally. To determine the existence of the phenomenon of land cover change in a region, it is necessary to identify the driving factors that can cause land cover change. The relation between driving factors and response variables can be evaluated by using regression analysis techniques. In this case, land cover change is a dichotomous phenomenon (binary). The BLR's model (Binary Logistic Regression) is the one of kind regression analysis which can be used to describe the nature of dichotomy. Before performing regression analysis, correlation analysis is carried it the first. Both correlation test and regression tests are part of a statistical test or known classical assumption test. From result of classical assumption test, then can be seen that the data used to perform analysis from driving factors of the land cover changes is proper with used by BLR's method. Therefore, the objective of this research is to evaluate the effectiveness of methods in assessing the relation between driving factors of land cover change that assumed can affect to land cover change phenomena. This research will use the classical assumed test of multiple regression linear analysis, showing that BLR method is efficiency and effectiveness solution for researching or studying in phenomenon of land cover changes. So it will to provide certainty that the regression equation obtained has accuracy in estimation, unbiased and consistent.

  10. EFFECT OF TILLAGE AND CHEMICALLY-WEEDED FALLOWING ON MEASURED WIND EROSION ON SUNFLOWER STUBBLE LAND IN THE NORTHERN GREAT PLAINS, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diversification of cropping systems in the northern Great Plains of the USA includes crop species with residues that are less durable than small cereal grains, creating potential wind erosion hazards under drought and tillage disturbance. No-tillage with chemical weed control is currently considered...

  11. Northern Plains 'Crater'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 December 2004 The lower left (southwest) corner of this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the location of a somewhat filled and buried meteor impact crater on the northern plains of Mars. The dark dots are boulders. A portion of a similar feature is seen in the upper right (northeast) corner of the image. This picture, showing landforms (including the odd mound north/northeast of the crater) that are typical of the martian northern lowland plains, was obtained as part of the MGS MOC effort to support the search for a landing site for the Phoenix Mars Scout lander. Phoenix will launch in 2007 and land on the northern plains in 2008. This image is located near 68.0oN, 227.4oW, and covers an area approximately 3 km (1.9 mi) wide. The scene is illuminated by sunlight from the lower left.

  12. New species of Metatrichia Coquillett (Diptera: Scenopinidae) from Australia and Venezuela

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two new species of the cosmopolitan genus Metatrichia Coquillett are described. Metatrichia dhimurru sp. nov. is described from Arnhem Land (Northern Territory), Australia and represents the third species of the genus to be described from the Australian-Papuan region. Metatrichia venezuelensis sp. n...

  13. Vulnerability of Coastal Crop Land to Climate Change in the Northern Part of Bay of Bengal: Issues, Challenges and Future Prospects

    NASA Astrophysics Data System (ADS)

    Kamal, A. H. M.

    2015-12-01

    The coastal communities of northeastern part of Bay of Bengal are used to live and survive through facing different types of natural disasters since primitive time. Among the natural disasters, salinity intrusion due to climate change and sea level rise in the coastal agriculture land is the major unpleasant incident now days. Because of that wide area of the coastal agricultural land, coastal forest, drinking water facilities and fresh water availability are in critical condition which may cause 40 million people of 147 coastal districts covering 47201 km area are placed in danger. The nation wide assessment on the detected of coastal soil and water salinity is not conducted since 9 years. The survey on the coastal soil salinity on 1973 and 2000 found that the saline effected land is increased from 0.83 million ha to 1.20 million ha within 27 years. It is assumed that at present the rate of salinity intrusion in the coastal agriculture land will be higher than those of 1973 and 2000. The soil salinity was recorded 18-20 psu after AILA in the south-eastern coast of Bangladesh and increased further 2-4 psu due to low precipitation which causes crop burning. This paper aims to know the salinity intrusion in the coastal soil and water of Bangladesh, which would help to plan and improvement of the sustainable agriculture production. Study revealed that to face any extra stresses on the coastal agriculture land due to climate change requires extensive inventory, awareness activities, mitigation measures, adaptation techniques and extension of indigenous technology.

  14. Aqueous and non-aqueous soil processes on the northern plains of Mars: Insights from the distribution of perchlorate salts at the Phoenix landing site and in Earth analog environments

    NASA Astrophysics Data System (ADS)

    Cull, Selby; Kennedy, Erin; Clark, Alice

    2014-06-01

    In 2008, the Phoenix lander returned chemical evidence of perchlorate salts in the soils at its landing site on the northern plains of Mars. Subsequent spectral mapping of the perchlorate using Phoenix's multispectral Surface Stereo Imager (SSI) showed that concentrated patches of the salt exist in the subsurface. Because atmospheric formation of Martian perchlorate should form a highly-concentrated layer of salt on the surface, subsurface concentrated patches have been interpreted as evidence that Phoenix soils experienced minor amounts of aqueous reworking after perchlorate formation. Here, we present results from a wide-scale mapping of the Phoenix landing site using SSI multispectral data. We report that, contrary to preliminary case studies, limited occurrences of rocks and soil clods with perchlorate coatings are also found on the undisturbed surface. The discovery of these patches on undisturbed surfaces points to more complex processes operating on modern-day polar soils, perhaps including a combination of aqueous and mechanical processes, such as cryoturbation. Finally, we combine results from this study with an analysis of perchlorate redistribution mechanisms on Earth to illustrate the mechanisms likely responsible for modern processing of soils on the northern plains of Mars. Concentrated perchlorate coatings found on the undisturbed surface at the Phoenix site. Phoenix soils likely processed by both aqueous and non-aqueous processes. Small-volumes of water likely responsible for producing perchlorate coatings. Non-aqueous mechanical processing could bring coated rocks back to the surface. Perchlorate may not be found on the top-most surface at equatorial sites.

  15. The Ross Orogen and Lachlan Fold Belt in Marie Byrd Land, Northern Victoria Land and New Zealand: implication for the tectonic setting of the Lachlan Fold Belt in Antarctica

    USGS Publications Warehouse

    Bradshaw, J.D.

    2007-01-01

    Correlation of the Cambrian Delamerian Orogen of Australia and Ross Orogen of the Transantarctic Mountains widely accepted but the extension of the adjacent Lachlan Orogen into Antarctica is controversial. Outside the main Ross-Delamerian belt, evidence of this orogeny is preserved at Mt Murphy in Marie Byrd Land and the in Takaka Terrane of New Zealand. In all pre-break- configurations of the SW Pacific, these two areas are far removed from the Ross-Delamerian belt. Evidence from conglomerates in the Takaka Terrane, however, shows that in Late Cambrian times it was adjacent to the Ross Orogen. This indicates major tectonic displacements within Gondwana after the Cambrian and before break-up. The Lachlan Orogen formed in an extensional belt in a supra-subduction zone setting and the Cambrian rocks of Marie Byrd Land and New Zealand are interpreted as parts of a rifted continental ribbon on the outboard side of the Lachlan belt.

  16. The pedological heritage of the Dolomites (Northern Italy): Features, distribution and evolution of the soils, with some implications for land management

    NASA Astrophysics Data System (ADS)

    Zilioli, Diana Maria; Bini, Claudio; Wahsha, Mohammad; Ciotoli, Giancarlo

    2011-12-01

    Since 1997, the Department of Environmental Sciences of Ca' Foscari University of Venice has undertaken numerous research projects aimed at deepening understanding of pedogenic processes in the Dolomites, and at highlighting the fundamental contribution that soil science can give to the conservation of natural resources and achieve sustainable management of mountain ecosystems. A total of several hundred profiles have been described, analyzed and mapped. This paper reports the results from the analysis of pedo-environmental characters of profiles developed from different parent materials, at altitudes between 1300 m and 2900 m and in different conditions of slope, exposure and vegetation cover. Soil forming factors, landforms and land surfaces have been interpreted to understand the soil-landscape in the mapped areas and to develop a qualitative model of soil geography into the Dolomites scenery. The application of land evaluation methods in some of the investigated territories that are subjected to intensive tourist fluxes revealed some criticisms. Collected results also highlighted the high environmental heterogeneity of soils of the Dolomites.

  17. CO2 and CH4 exchanges between land ecosystems and the atmosphere in northern high latitudes over the 21st century

    USGS Publications Warehouse

    Zhuang, Q.; Melillo, J.M.; Sarofim, M.C.; Kicklighter, D.W.; McGuire, A.D.; Felzer, B.S.; Sokolov, A.; Prinn, R.G.; Steudler, P.A.; Hu, S.

    2006-01-01

    Terrestrial ecosystems of the northern high latitudes (above 50??N) exchange large amounts of CO2 and CH4 with the atmosphere each year. Here we use a process-based model to estimate the budget of CO 2 and CH4 of the region for current climate conditions and for future scenarios by considering effects of permafrost dynamics, CO 2 fertilization of photosynthesis and fire. We find that currently the region is a net source of carbon to the atmosphere at 276 Tg C yr -1. We project that throughout the 21st century, the region will most likely continue as a net source of carbon and the source will increase by up to 473 Tg C yr-1 by the end of the century compared to the current emissions. However our coupled carbon and climate model simulations show that these emissions will exert relatively small radiative forcing on global climate system compared to large amounts of anthropogenic emissions. Copyright 2006 by the American Geophysical Union.

  18. Comparing results of high-resolution palaeoecological analyses with oral histories of land-use of a Sami reindeer herding pen in northern Sweden

    NASA Astrophysics Data System (ADS)

    Kamerling, Ilse M.; Edwards, Kevin J.; Schofield, James E.; Aronsson, Kjell-Åke

    2016-04-01

    Reindeer herding is a key component of Sami culture, but much is still unknown about its development both in the recent and more distant past due to the limited availability of historical and archaeological evidence. Pollen analysis provides a potential tool to supplement this lack of evidence through the detection and evaluation of landscape responses to the impact of reindeer pastoralism. In the boreal forests of northern Fennoscandia, localised forest clearance to create space for dwellings and livestock is presented in the palynological record as a decline in arboreal taxa and an increase in herbaceous taxa favoured by the increased light levels, resistance to soil trampling, and/or the increased soil nutrient levels provided by reindeer dung, domestic waste and ash from smudge fires. Oral histories of 20th century forest Sami reindeer herding at an abandoned reindeer herding pen (renvall) at Akkajävi, northern Sweden (66.9° N, 21.1° E), are integrated here with high-resolution palaeoecological reconstructions of the local vegetation to: (i) assess the sensitivity and value of various palynomorphs to the impacts of reindeer pastoralism; (ii) investigate whether the patterns seen in the palaeoecological record match the timing of activity at and abandonment of the site as understood from these oral histories. A peat monolith collected from within an annexe of the renvall was pollen analysed at a high resolution, supplemented with coprophilous fungal spore (livestock grazing/gathering), microscopic charcoal ([anthropogenic] burning) and sedimentological (loss-on-ignition; soil erosion) records. For the first time, this has allowed for the identification of multi-decadal cycles of use and abandonment of a renvall in the pollen record, but more obviously so in its coprophilous fungal spore archive, with the pattern and timing of changes at the site confirming events previously known only from oral histories. A second, paired profile was collected from the fen

  19. De-confounding of Relations Between Land-Level and Sea-Level Change, Humboldt Bay, Northern California: Uncertain Predictions of Magnitude and Timing of Tectonic and Eustatic Processes

    NASA Astrophysics Data System (ADS)

    Gilkerson, W.; Leroy, T. H.; Patton, J. R.; Williams, T. B.

    2010-12-01

    Humboldt Bay in Northern California provides a unique opportunity to investigate the effects of relative sea level change on both native flora and maritime aquiculture as influenced by both tectonic and eustatic sea-level changes. This combination of superposed influences makes quantitatively predicting relative sea-level more uncertain and consumption of the results for public planning purposes exceedingly difficult. Public digestion for practical purposes is confounded by the fact that the uncertainty for eustatic sea-level changes is a magnitude issue while the uncertainty associated with the tectonic land level changes is both a magnitude and timing problem. Secondly, the public is less well informed regarding how crustal deformation contributes to relative sea-level change. We model the superposed effects of eustatic sea-level rise and tectonically driven land-level changes on the spatial distribution of habitats suitable to native eelgrass (Zostera marina) and oyster mariculture operations in Humboldt Bay. While these intertidal organisms were chosen primarily because they have vertically restricted spatial distributions that can be successfully modeled, the public awareness of their ecologic and economic importance is also well developed. We employ easy to understand graphics depicting conceptual ideas along with maps generated from the modeling results to develop locally relevant estimates of future sea level rise over the next 100 years, a time frame consistent with local planning. We bracket these estimates based on the range of possible vertical deformation changes. These graphic displays can be used as a starting point to propose local outcomes from global and regional relative sea-level changes with respect to changes in the distribution of suitable habitat for ecologically and economically valuable species. Currently the largest sources of uncertainty for changes in relative sea-level in the Humboldt Bay area are 1) the rate and magnitude of tectonic

  20. Stable Isotopic signatures of Adélie penguin remains provide long-term paleodietary records in Northern Victoria Land (Ross Sea, Antarctica)

    NASA Astrophysics Data System (ADS)

    Lorenzini, Sandra; Baroni, Carlo; Fallick, Anthony Edward; Baneschi, Ilaria; Salvatore, Maria Cristina; Zanchetta, Giovanni; Dallai, Luigi

    2010-05-01

    The stable isotopes geochemistry of carbon and nitrogen provides a powerful tools for investigating in animal dietary patterns and shifts during the past. The signature of C and N isotopes provide direct information about the diet of an individual and its dietary patterns, especially when the dietary sources consist of prey from different trophic levels (i.e. different C and N isotopic composition) (DeNiro and Epstein 1978, Minawaga and Wada 1984, Koch et al. 1994, Hobson 1995). By analyzing the isotopic composition of penguin remains, we present a new detailed Adélie penguin (Pygoscelis adeliae) paleodietary record for the area of Terra Nova Bay (Victoria Land, Ross Sea). Adélie penguins primarily feed on fish (mainly the silverfish Pleuragramma antarcticum) and krill (Euphausia superba, Euphausia cristallorophias) (Ainley 2002, Lorenzini et al. 2009) that belonging to two different trophic levels. Consequently, they are characterized by different isotopic signatures. Specifically, we analyzed 13C/12C and 15N/14N ratios of more than one thousand of modern and fossil Adélie penguin eggshell and guano samples collected from ornithogenic soils (penguin guano-formed) dated back to ≈7,200 years BP (Baroni and Orombelli 1994, Lambert et al. 2002, Baroni and Hall 2004, Hall et al. 2006). The expanded database of stable isotope values obtained from Adélie penguin remains define a detailed paleodietary record with an excellent temporal continuity over all the investigated time period. Our data indicate a significant dietary shift between fish and krill, with a gradual decrease from past to present time in the proportion of fish compared to krill in Adélie penguin diet. From 7200 yrs BP to 2000 yrs BP, δ13C and δ15N values indicate fish as the most eaten prey. The dietary contribution of lower-trophic prey in penguin diet started becoming evident not earlier than 2000 yrs BP, when the δ13C values reveal a mixed diet based on fish and krill consumption. Modern

  1. Effectiveness of soil and water conservation structures in reducing runoff and soil loss for different land use and slope gradients: Case study from northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Taye, Gebeyehu; Poesen, Jean; Vanwesemael, Bas; Vanmaercke, Matthias; Teka, Daniel; Deckers, Jozef; Goosse, Tom; Maetens, Willem; Nyssen, Jan; Hallet, Vincent; Haregeweyn, Nigussie

    2014-05-01

    Land degradation and recurrent drought are the major threats to rain-fed agriculture in the semi-arid Ethiopian highlands. To mitigate drought and to ensure food security in the Tigray region, water harvesting using reservoirs for irrigation development has become a priority since 1990. However, the success of water harvesting in reservoirs is limited due to the reduced inflow. As a result, less area is irrigated than originally planned. The aim of this study is to investigate the effectiveness of soil and water conservation (SWC) structures in reducing runoff and soil loss under different land use types and slope gradients. Six runoff measuring sites, corresponding to three slope gradients (5%, 12% and 16%) were established for cropland and rangeland in the Mayleba catchment (Tigray). In total, 21 large runoff plots (with lengths of 60 to 100 m and widths of 10 m) were monitored daily for runoff production and soil loss during the main rainy season (July-September) in 2010. For each site in cropland, three plots were installed and treated with stone bunds and stone bunds with trenches in addition to a control plot. At each site in rangeland four runoff plots were installed: a plot treated with stone bunds, a plot treated with trenches, a plot treated with stone bunds and trenches as well as a control plot. Overall uncertainties on the runoff and soil loss measurements were estimated by means of Monte Carlo simulation techniques. The results show that the seasonal runoff coefficient (RCs) was much higher for rangeland (0.38 < RCs < 0.50) compared to RCs-values for cropland (0.11 < RCS < 0.15). Seasonal soil loss (SLs) values were five to six times larger on rangeland (28.6 < SLs < 50.0 ton ha-1) compared to that for cropland (4.6 < SLs < 11.4 ton ha-1). All tested SWC structures are effective in reducing runoff and soil loss compared to control plots. However, reduction in RCs were relatively much smaller than reductions in SLs. Trenches and stone bunds with

  2. Modelling of the effect of a sea-level rise and land subsidence on the evolution of the groundwater density in the subsoil of the northern part of the Netherlands

    NASA Astrophysics Data System (ADS)

    van der Meij, J. L.; Minnema, B.

    1999-12-01

    NAGROM, based on the analytic element method ( Strack, 1989). NAGROM is a national water management tool for evaluating different water conservation and distribution policies. It was developed by the Institute for Inland Water Management and Waste Water Treatment in co-operation with The Netherlands Institute of Applied Geoscience TNO (NITG-TNO). The effect of a sea-level rise and land subsidence was calculated for a 50-year period. Salinization of the surface waters by discharged groundwater in the Northern part of The Netherlands was compared with the evolution of the region not including sea-level rise and land subsidence. The amount of saline discharge as part of the surface water balance was calculated under special boundary conditions set according to the proposed sea-level rise and land subsidence in a semi-unsteady state.

  3. The influence of lithology, land cover, road network and slope gradient in the landslides triggered during the period November 2008 - February 2009 in northern Tuscany (Italy)

    NASA Astrophysics Data System (ADS)

    Segoni, Samuele; Mucci, Alessandra; Casagli, Nicola

    2010-05-01

    In the provinces of Lucca and Pistoia (Tuscany, Central Italy) 650 landslides (mainly shallow rapid slides and debris flows) were registered by Civil Protection during the period spanning from November 2008 to February 2009. During that period both provinces were struck by widespread precipitations: in November three distinct brief but very intense events brought the monthly precipitation well above the mean value, while the month of December was conversely characterized by heavy and prolonged precipitations whose cumulative amount doubled the monthly mean value. During January and February brief and intense precipitations struck again diffusively the whole studied area. As a consequence of such a prolonged period of abundant rainfall, hundreds of landslides occurred in the provinces of Lucca and Pistoia damaging private and public buildings, assets and infrastructures. The state of emergency was declared by the National Civil Protection from December to February. Rainfall has been without doubt the triggering factor of the landslides, but can some predisposing feature be identified? The answer is decisive for improving risk assessments and for developing effective emergency plans for civil protection purposes. For example, rainfall thresholds can be easily used to set up warning systems that can forecast the time of occurrence of landslides but such methods have a very coarse spatial resolution: the identification of predisposing elements could be helpful to identify the most risky locations in order to reduce the spatial uncertainty. From the Provincial and Regional Civil Protection archives many information about the occurred landslides were gathered and organized into a geographic database making use of a GIS system. Data include the exact location and day of occurrence of the landslides and their type. By means of a GIS analysis, the landslides database was superimposed to various thematic maps (geology, land cover, road network, slope gradient) in order to

  4. Estimating the Mean Annual Surface Air Temperature at Armagh Observatory, Northern Ireland, and the Global Land-Ocean Temperature Index for Sunspot Cycle 24, the Current Ongoing Sunspot Cycle

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.

    2013-01-01

    As noted by Gray et al., Sir William Herschel was the first to suggest a possible close connection between the Sun and the Earth’s climate. The Sun, being the source of energy that impacts and drives the Earth’s climate system, displays a variety of changes over both short and long term time scales, the most obvious examples being the somewhat regular waxing and waning of sunspots with time (i.e., the sunspot cycle (SC)), first described by Samuel Heinrich Schwabe, a German apothecary and amateur astronomer who observed the Sun from Dessau, Germany, and the now well established variation of the Sun’s irradiance over the SC. Other factors related to the SC have been linked to changes in climate as well. Some of these other factors include the role of cosmic rays and the solar wind (i.e., the geomagnetic cycle) on climate, as well as the apparent close association between trends in global and northern hemispheric temperature and the length of the SC, although some investigators have described the inferred association between climate and, in particular, SC length as now being weak. More recently, Solheim et al. have reported on the relation between SC length and the average temperature in the same and immediately following SC for a number of meteorological stations in Norway and in the North Atlantic region. They noted that while they found no significant trend (correlation) between SC length and the average temperature when measured for the same cycle, in contrast, they found a significant negative trend when SC length was compared with the following cycle’s average temperature. From this observation, they suggested that average northern hemispheric temperature during the present ongoing SC (SC24) will be lower by about 0.9 °C than was seen in SC23 (spanning 1996–2007, based on yearly averages of sunspot number (SSN), and onset for SC24 occurring in 2008). The purpose of this Technical Publication (TP) is to examine the annual variations of the Armagh

  5. Northern Nutrition.

    ERIC Educational Resources Information Center

    Northwest Territories Dept. of Education, Yellowknife.

    This guide contains nutrition information and nutrition education strategies aimed at residents of the Canadian Arctic. Section I: (1) defines nutrition terms; (2) describes the sources and functions of essential nutrients; (3) explains Canada's food guide and special considerations for the traditional northern Native diet and for lactose…

  6. A bill to convey certain submerged lands to the Commonwealth of the Northern Mariana Islands in order to give that territory the same benefits in its submerged lands as Guam, the Virgin Islands, and American Samoa have in their submerged lands.

    THOMAS, 112th Congress

    Sen. Bingaman, Jeff [D-NM

    2011-03-15

    05/18/2011 Committee on Energy and Natural Resources Subcommittee on Public Lands and Forests. Hearings held. With printed Hearing: S.Hrg. 112-39. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  7. Climate change versus land management in the Po Plain (Northern Italy) during the Bronze Age: New insights from the VP/VG sequence of the Terramara Santa Rosa di Poviglio

    NASA Astrophysics Data System (ADS)

    Cremaschi, Mauro; Mercuri, Anna Maria; Torri, Paola; Florenzano, Assunta; Pizzi, Chiara; Marchesini, Marco; Zerboni, Andrea

    2016-03-01

    The sedimentary infilling of the moat surrounding the Villaggio Piccolo of the Terramara Santa Rosa di Poviglio was analysed in order to obtain palaeoenvironmental inferences from sediments and pollen assemblage. The high-resolution stratigraphic sequence preserves evidence of the environmental changes that occurred in the Po Plain, in Northern Italy, during the Late Holocene. Our interdisciplinary approach permitted to study climatic and anthropic contributions to the environmental changes in this region. The relationships between these changes and land-use changes were investigated focussing on adaptive strategies of the Terramare people during the Middle and Recent Bronze ages (1550-1170 yr BC). The Terramare are archaeological remains of banked and moated villages, located in the central alluvial plain of the Po river. The Terramara of Santa Rosa consists of two adjoining settlements (Villaggio Grande and Villaggio Piccolo); the moat that separates the two parts of the site is c. 23 m large and reaches a maximum depth of 4 m from the extant ground level. The stratigraphic sequence VP/VG exposed by archaeological excavation inside the moat was sampled for pedosedimentary, thin section, and pollen analyses. Chronology is based on archaeological evidence, stratigraphic correlations and radiocarbon dating. Pedosedimentary features and biological records (pollen of aquatics and algal remains) demonstrate that shallow water, probably subjected to seasonal water-level oscillations, has always been present in the moat. In the lower units of the sequence, the laminations indicate standing water, while occurrence of reworked pollen testified the supply of sediments to the plain from catchment zones located in the Apennine. Open vegetation was widespread; economy was based on wood management, fruit collection on the wild or from cultivated woody plants, crop fields with a fairly diversified set of cereals especially increasing in variety during dryness or phases of water

  8. Tornadoes Strike Northern Wisconsin

    NASA Technical Reports Server (NTRS)

    2007-01-01

    A series of tornadoes ripped through the Upper Midwest region of the United States in the evening of June 7, 2007. At least five different tornadoes touched down in Wisconsin, according to the Associated Press, one of which tore through the Bear Paw Resort in northern Wisconsin. Despite dropping as much as fifteen centimeters (six inches) of rain in some places and baseball-size hail in others, authorities were reporting no deaths attributable to the storm system, and only a smattering of injuries, but considerable property damage in some areas. When the MODIS instrument on NASA's Terra satellite observed the area on June 9, 2007, the track torn through the woods by one of the tornadoes stands out quite clearly. This photo-like image uses data collected by MODIS in the normal human vision range to give a familiar natural-looking appearance. The landscape is largely a checkerboard of farms, towns, roads, and cities. The pale land is predominantly farmland where crops have not fully grown in yet. Dark blue shows the winding path of rivers and lakes dotting the landscape. The large blue lake on the east (right) side of the image is Lake Michigan. Towns and cities, including the city of Green Bay, are gray. To the north side, farmland gives way to dark green as land use shifts from agriculture to the Menominee Indian Reservation and Nicolet National Forest. The diagonal slash through the dark green forested land shows the tornado track. Bare land was revealed where the tornado tore down trees or stripped vegetation off the branches. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

  9. Roots of Resistance: Land Tenure in New Mexico, 1680-1980. Monograph Number 10.

    ERIC Educational Resources Information Center

    Ortiz, Roxanne Dunbar

    Focusing on land tenure patterns from 1860 to 1980, this study is a chronological socioeconomic interpretation of the history of northern New Mexico. Chapter One describes the development of the Pueblo Indian land use system prior to colonization. Chapter Two deals with the first colonial period (1598-1693) of land tenure in northern New Mexico.…

  10. Governance and Aboriginal Claims in Northern Canada.

    ERIC Educational Resources Information Center

    Cozzetto, Don

    1990-01-01

    Focuses on problems of organization and governance that may follow settlement of Canadian aboriginal land claims. Compares financial problems, cultural issues such as subsistence lifestyles, and intergovernmental relations following the Alaska Native Claims Settlement Act, James Bay and Northern Quebec Agreement, and Western Arctic (Inuvialuit)…