search
Include:
The following results are related to Rural Digital Europe. Are you interested to view more results? Visit OpenAIRE - Explore.
22,412 Research products, page 1 of 2,242

  • Rural Digital Europe
  • Open Access
  • Other literature type
  • 01 natural sciences
  • 0105 earth and related environmental sciences
  • English

10
arrow_drop_down
Relevance
arrow_drop_down
  • Open Access English
    Authors: 
    Luca Lanci; Barbara Delmonte; Valter Maggi; Jean-Robert Petit; Dennis V. Kent;
    Publisher: HAL CCSD
    Country: France

    International audience; Isothermal remanent magnetization and insoluble dust content of ice samples from EPICA-Dome C ice core were measured to characterize the magnetic properties of atmospheric dust. Despite the larger concentration of dust aerosol during glacial stages, the magnetization of the dust fraction was found to be higher during interglacials and exhibits a larger variability. Changes in magnetic mineralogy of aerosol dust in ice from different climatic stages were also characterized using coercivity of remanence. Variations of magnetic properties of dust from glacial to interglacial stages indicate changes in dust provenance, in agreement with previous results based on geochemical analysis. However, the extremely large magnetizations of some interglacial samples also suggest that episodical eolian deposition from highly magnetic deposits occurred during interglacial periods.

  • Open Access English
    Authors: 
    Cyriac S. Mvolo; Ahmed Koubaa; Jean Beaulieu; Alain Cloutier;
    Publisher: Multidisciplinary Digital Publishing Institute

    So far, few studies have considered the impacts of seed sources transfer on jack pine (Pinus banksiana Lamb.) wood quality, although wood quality attributes (WQA) in general and the differences between juvenile and mature wood in particular will determine suitability of the produced wood for end-uses. The main objective of this study was to examine the possibility of selecting superior jack pine provenances based on selected WQA. Twenty-two provenances of jack pine were planted in 1964 in Petawawa Research Forest, ON, Canada, as part of a provenance test. The plantation location offers conditions close to optimum for jack pine growth. Transition ages at breast height, determined with tracheids length, were computed with a piecewise model. Measurements at age 42 from seed were subjected to analyses of variance. Radial variations from pith to bark, as well as trends with seed sources origin of the selected WQA were also considered. A ranking was made based on a selection index built with four WQA. The provenances matured between 8 and 14 years, corresponding to 17%&ndash 48% of juvenile wood proportion. Significant differences among provenances were observed for ring width, ring density, tracheid length, and diameter at breast height but not for tracheid diameter, tree height, transition age, and juvenile wood proportion. None of the provenances ranked the best with all the selected WQA, but it was possible to find provenances exhibiting both high growth rate and good wood quality. A surprising result of this study was that tracheid diameter initially enlarged for 8 years, before declining toward the bark. It is possible to select provenances for a higher growth rate and for good physical (i.e., related to wood density) and anatomical (i.e., related to tracheid dimensions) wood quality attributes.

  • Open Access English
    Authors: 
    N. Boja; F. Boja; Alin Teusdea; Dan Vidrean; Marina Viorela Marcu; Eugen Iordache; Cristian Ionuţ Duţă; Stelian Alexandru Borz;
    Publisher: Multidisciplinary Digital Publishing Institute

    Afforestation and reforestation operations constitute an important part of the forest management, being crucial for the sustainability of forests. In such operations, there are three options to prepare the planting holes: manual, partly mechanized, and fully mechanized. Given the high cost of mechanized planting and the ergonomic issues of manual planting, one option which is worth exploring is using of augers, because they have the potential to mitigate and/or eliminate intense physical effort and aspects of some of the ergonomic problems. This study examines the early survival of seedlings following the use of augers to prepare the planting pits. Working time, fuel consumption and physical quality of the pits were evaluated on nine sites for two drill types differentiated by their diameter (150 vs. 200 mm). Time consumption was systematically higher when using the larger drill, while fuel consumption was not found to be statistically different. The larger drill systematically produced pits characterized by less physical quality in terms of resistance to penetration and shear strength, but the early survival of seedlings was higher when using this drill size. Survival probability modeled by means of logistic regression showed that pit size was among the factors that may affect the early survival of seedlings. The study concludes that the larger drill would be more appropriate to plant seedlings, but further studies should be arranged to see if long-term survival would be affected in this case.

  • Open Access English
    Authors: 
    Zulkepli Majid; C. L. Lau; Ahmad Razali Yusoff;
    Publisher: Copernicus Publications

    Abstract. This paper describes the use of terrestrial laser scanning for the full three-dimensional (3D) recording of historical monument, known as the Bastion Middleburg. The monument is located in Melaka, Malaysia, and was built by the Dutch in 1660. This monument serves as a major hub for the community when conducting commercial activities in estuaries Malacca and the Dutch build this monument as a control tower or fortress. The monument is located on the banks of the Malacca River was built between Stadhuys or better known as the Red House and Mill Quayside. The breakthrough fort on 25 November 2006 was a result of the National Heritage Department through in-depth research on the old map. The recording process begins with the placement of measuring targets at strategic locations around the monument. Spherical target was used in the point cloud data registration. The scanning process is carried out using a laser scanning system known as a terrestrial scanner Leica C10. This monument was scanned at seven scanning stations located surrounding the monument with medium scanning resolution mode. Images of the monument have also been captured using a digital camera that is setup in the scanner. For the purposes of proper registration process, the entire spherical target was scanned separately using a high scanning resolution mode. The point cloud data was pre-processed using Leica Cyclone software. The pre-processing process starting with the registration of seven scan data set through overlapping spherical targets. The post-process involved in the generation of coloured point cloud model of the monument using third-party software. The orthophoto of the monument was also produced. This research shows that the method of laser scanning provides an excellent solution for recording historical monuments with true scale of and texture.

  • Open Access English
    Authors: 
    Gottfried Mandlburger; Norbert Pfeifer; Uwe Soergel;

    Abstract. In airborne laser bathymetry knowledge of exact water level heights is a precondition for applying run-time and refraction correction of the raw laser beam travel path in the medium water. However, due to specular reflection especially at very smooth water surfaces often no echoes from the water surface itself are recorded (drop outs). In this paper, we first discuss the feasibility of reconstructing the water surface from redundant observations of the water bottom in theory. Furthermore, we provide a first practical approach for solving this problem, suitable for static and locally planar water surfaces. It minimizes the bottom surface deviations of point clouds from individual flight strips after refraction correction. Both theoretical estimations and practical results confirm the potential of the presented method to reconstruct water level heights in dm precision. Achieving good results requires enough morphological details in the scene and that the water bottom topography is captured from different directions.

  • Open Access English
    Authors: 
    Hao Zhang; Kelin Wang; Zhaoxia Zeng; Zhigang Zou; Yanfang Xu; Fuping Zeng;
    Publisher: MDPI AG

    The roots linking the above-ground organs and soil are key components for estimating net primary productivity and carbon sequestration of forests. The patterns and drivers of root biomass in forest have not been examined well at the regional scale, especially for the widely distributed forest ecosystems in southwestern China. We attempted to determine the spatial patterns of root biomass (RB, Mg/ha), annual increment root biomass (AIRB, Mg/ha/year), ratio of root and above-ground (RRA), and the relative contributions of abiotic and biotic factors that drive the variation of root biomass. Forest biomass and multiple factors (climate, soil, forest types, and stand characteristics) of 318 plots in this region (790,000 km2) were analyzed in this research. The AB (the mean values for forest aboveground biomass per ha, Mg/ha), RB, AIRB, and RRA were 126 Mg/ha, 28 Mg/ha, 0.69 Mg/ha and 0.22, respectively. AB, RB, AIRB, and RRA varied across all the plots and forest types. Both RB and AIRB showed significant spatial patterns of distribution, while RRA did not show any spatial patterns of distribution. Up to 28.4% of variation in total of RB, AIRB, and RRA can be attributed to the climate, soil, and stand characteristics. The explained or contribution rates of climate, soil, and stand characteristics for variation of whole forest root biomass were 6.7%, 16.9%, and 10.9%, respectively. Path analysis in structural equation model (SEM) indicated the direct influence of stand age on RB. AIRB was greater than that of the other factors. Climate, soil and stand characteristics in different forest types could explain 9.7%&ndash 99.4% of variations in RB, AIRB, and RRA, respectively, which suggests that the multiple factors may be important in explaining the variations in forest root biomass. The results of the analysis of root biomass per ha, annual increment of root biomass per ha, and ratio of root and above-ground in the seven forest types categorized by climate, soil, and stand characteristics may be used for accurately determining C sequestration by the forest root and estimating forest biomass in this region. 96.4%, and 36.7%&ndash 96.1%, 15.4%&ndash

  • Open Access English
    Authors: 
    Emily Walker; Pascal Monestiez; Cécile Gomez; Philippe Lagacherie;
    Publisher: HAL CCSD
    Country: France
    Project: ANR | DIGISOL-HYMED (ANR-08-BLAN-0284)

    International audience; The limited availability of soil information has been recognized as a main limiting factor in digital soil mapping (DSM) studies. It is therefore important to optimize the joint use of the three sources of soil data that can be used as inputs of DSM models, namely spatial sets of measured sites, soil maps and soil sensing products.In this paper, we propose to combine these three inputs, through a cokriging with a categorical external drift (CKCED). This new interpolation technique was applied for mapping seven soil properties over a 24.6 km2 area located in the vineyard plain of Languedoc (Southern France), using an hyperspectral imagery product as example of a soil sensing data. Cross-validation results of CKCED were compared with those of five spatial and non-spatial techniques using one of these inputs or a combination of two of them.The results obtained in the La Peyne Catchment showed i) the utility of soil map and hyperspectral imagery products as auxiliary data for improving soil property predictions ii) the greater added-value of the latter against the former in most situations and iii) the feasibility and the interest of CKCED in a limited number of soil properties and data configurations. Testing CKCED in case study with soil maps of better quality and soil sensing techniques covering more area and depths should be necessary to better evaluate the benefits of this new technique.

  • Open Access English
    Authors: 
    Kevin Barnett; Sean A. Parks; Carol Miller; Helen T. Naughton;
    Publisher: Multidisciplinary Digital Publishing Institute

    In the United States, fuel reduction treatments are a standard land management tool to restore the structure and composition of forests that have been degraded by past management. Although treatments can have multiple purposes, their principal objective is to create landscape conditions where wildland fire can be safely managed to help achieve long-term land management goals. One critique is that fuel treatment benefits are unlikely to transpire due to the low probability that treated areas will be burned by a subsequent fire within a treatment’s lifespan, but little quantitative information exists to corroborate this argument. We summarized the frequency, extent, and geographic variation of fire and fuel treatment interactions on federal lands within the conterminous United States (CONUS). We also assessed how the encounters between fuel treatments and fires varied with treatment size, treatment age, and number of times treated. Overall, 6.8% of treatment units evaluated were encountered by a subsequent fire during the study period, though this rate varied among ecoregions across the CONUS. Larger treatment units were more likely to be encountered by a fire, and treatment units were most frequently burned within one year of the most recent treatment, the latter of which is likely because of ongoing maintenance of existing treatments. Our results highlight the need to identify and prioritize additional opportunities to reduce fuel loading and fire risk on the millions of hectares of federal lands in the CONUS that are in need of restoration.

  • Open Access English
    Authors: 
    T. Maharajan; Stanislaus Antony Ceasar; Thumadath Palayullaparambil Ajeesh Krishna; M. Ramakrishnan; Veeramuthu Duraipandiyan; Al-Dhabi Naif Abdulla; Savarimuthu Ignacimuthu;
    Publisher: Blackwell (GB)
    Country: Belgium

    Phosphorus (P) is the second most growth limiting macronutrient after nitrogen and plays several important roles in all organisms including plants. In soil, P is available in both organic and inorganic forms. P deficiency reduces the growth and yield of several crop plants. Plants respond to P deficiency by the phenotypic changes especially by the modification of root architecture. Molecular marker-assisted breeding (MAB) has been proposed as an important tool to identify and develop improved varieties of crop plants with efficient P-use efficiency (PUE). Identification of quantitative trait loci (QTLs) for traits related to PUE has been considered as the first step in marker-assisted selection (MAS) and improvement of crop yield programmes. In this review, we describe in detail on architectural changes of roots under P deficiency that are reported in various crops and discuss the efforts made to improve PUE using molecular marker tools. Details on QTLs identified for low P-stress tolerance in various crop plants are presented. These QTLs can be used to improve PUE in crop plants through MAS and breeding, which may be beneficial to improve the yields under P-deficient soil. Development of new and improved varieties using MAB will limit the use of non-renewable fertilizers and improve PUE of key crop plants in low input agriculture.

  • Publication . Article . Other literature type . 2021
    Open Access English
    Authors: 
    Valentin Bellassen; Marion Drut; Federico Antonioli; Ružica Brečić; Michele Donati; Hugo Ferrer-Pérez; Lisa Gauvrit; Viet Hoang; Kamilla Knutsen Steinnes; Apichaya Lilavanichakul; +11 more
    Publisher: HAL CCSD
    Countries: Croatia, Netherlands, France
    Project: EC | Strength2Food (678024)

    Abstract The carbon and land footprint of 26 certified food products – geographical indications and organic products and their conventional references are assessed. This assessment goes beyond existing literature by (1) designing a calculation method fit for the comparison between certified food and conventional production, (2) using the same calculation method and parameters for 52 products – 26 Food Quality Schemes and their reference products – to allow for a meaningful comparison, (3) transparently documenting this calculation method and opening access to the detailed results and the underlying data, and (4) providing the first assessment of the carbon and land footprint of geographical indications. The method used is Life Cycle Assessment, largely relying on the Cool Farm Tool for the impact assessment. The most common indicator of climate impact, the carbon footprint expressed per ton of product, is not significantly different between certified foods and their reference products. The only exception to this pattern are vegetal organic products, whose carbon footprint is 16% lower. This is because the decrease in greenhouse gas emissions from the absence of mineral fertilizers is never fully offset by the associated lower yield. The climate impact of certified food per hectare is however 26% than their reference and their land footprint is logically 24% higher. Technical specifications directly or indirectly inducing a lower use of mineral fertilizers are a key driver of this pattern. So is yield, which depends both on terroir and farming practices. Overall, this assessment reinforces the quality policy of the European Union: promoting certified food is not inconsistent with mitigating climate change.