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1.
Sci Total Environ ; 913: 169692, 2024 Feb 25.
Article in English | MEDLINE | ID: mdl-38160816

ABSTRACT

To enhance our understanding of forest carbon sequestration, climate change mitigation and drought impact on forest ecosystems, the availability of high-resolution annual forest growth maps based on tree-ring width (TRW) would provide a significant advancement to the field. Site-specific characteristics, which can be approximated by high-resolution Earth observation by satellites (EOS), emerge as crucial drivers of forest growth, influencing how climate translates into tree growth. EOS provides information on surface reflectance related to forest characteristics and thus can potentially improve the accuracy of forest growth models based on TRW. Through the modelling of TRW using EOS, climate and topography data, we showed that species-specific models can explain up to 52 % of model variance (Quercus petraea), while combining different species results in relatively poor model performance (R2 = 13 %). The integration of EOS into models based solely on climate and elevation data improved the explained variance by 6 % on average. Leveraging these insights, we successfully generated a map of annual TRW for the year 2021. We employed the area of applicability (AOA) approach to delineate the range in which our models are deemed valid. The calculated AOA for the established forest-type models was 73 % of the study region, indicating robust spatial applicability. Notably, unreliable predictions predominantly occurred in the climate margins of our dataset. In conclusion, our large-scale assessment underscores the efficacy of combining climate, EOS and topographic data to develop robust models for mapping annual TRW. This research not only fills a critical void in the current understanding of forest growth dynamics but also highlights the potential of integrated data sources for comprehensive ecosystem assessments.


Subject(s)
Ecosystem , Remote Sensing Technology , Forests , Trees , Climate Change , Europe, Eastern , Europe
2.
Materials (Basel) ; 16(7)2023 Mar 25.
Article in English | MEDLINE | ID: mdl-37048909

ABSTRACT

The research on Paulownia cultivation and wood properties is up to date in many countries. However, there are no data on the properties of this wood defined on a microscale, on microtome samples. The main aim of this study was to find the best valorization path for the wood of Paulownia Shang Tong Hybrid F1 from an extensively cultivated plantation established in April 2017 in Poland by determining the tensile strength, the wood density, the strength-to-density ratio, and the modulus of elasticity on a cross-section of the trunk. The wood was collected from extensive plantation, where production is based on the natural resources of the habitat and ambient weather conditions, which is the opposite to the intensive cultivation model, which is the recommended model of Paulownia cultivation. The results of this study show that the mean density of the analyzed samples was approximately 210 kg/m3 when the mean value of the modulus of elasticity (MOE) was approximately 2400 MPa. The mean result for the tensile strength ratio to density was 11.25 km. In the case of anatomical structure, the increasing trend with age was noticed both in fiber and vessel characteristics. The study results provide unique data worldwide about Paulownia wood's properties based on a cross-section of the trunk, from plantations cultivated in conditions which are not recommended by seedlings producers. The obtained data indicate that the Paulownia wood (examined) from the cultivation in this study has a technical quality similar to that of model-intensive agricultural plantations.

3.
Nanoscale ; 13(16): 7685-7693, 2021 Apr 30.
Article in English | MEDLINE | ID: mdl-33928952

ABSTRACT

The Dzyaloshinskii-Moriya interaction (DMI) manifesting in asymmetric layered ferromagnetic films gives rise to non-colinear spin structures stabilizing magnetization configurations with nontrivial topology. In this work magnetization reversal, magnetic domain alignment, and strength of DMI are related to the crystalline structure of W/Co/Pt multilayers grown by molecular beam epitaxy. The applied growth method enables the fabrication of layered systems with higher crystalline quality than commonly applied sputtering techniques. A relatively high value of the D coefficient was determined from the aligned magnetic domain stripe structure, substantially exceeding 2 mJ m-2. The highest value of DMI strength Deff = 2.64 mJ m-2 and surface DMI parameter DS = 1.83 pJ m-1 have been observed for a repetition number equal to 10. The experimental results correlate exactly with those obtained from the micromagnetic modelling and density functional theory calculations performed for the well-defined layered stacks. This high value of DMI strength originates from the additive contributions of the interfacial atomic Co layers at the two types of interfaces.

4.
Rev Sci Instrum ; 89(10): 10E116, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399980

ABSTRACT

Wendelstein 7-X aims at quasi-steady state operation with up to 10 MW of heating power for 30 min. Power exhaust will be handled predominantly via 10 actively water cooled CFC (carbon-fiber-reinforced carbon) based divertor units designed to withstand power loads of 10 MW/m2 locally in steady state. If local loads exceed this value, a risk of local delamination of the CFC and failure of entire divertor modules arises. Infrared endoscopes to monitor all main plasma facing components are being prepared, and near real time software tools are under development to identify areas of excessive temperature rise, to distinguish them from non-critical events, and to trigger alarms. Tests with different cameras were made in the recent campaign. Long pulse operation enforces additional diagnostic design constraints: for example, the optics need to be thermally decoupled from the endoscope housing. In the upcoming experimental campaign, a graphite scraper element, in front of the island divertor throat, will be tested as a possible means to protect the divertor pumping gap edges during the transient discharge evolution.

5.
Ann Agric Environ Med ; 24(3): 401-405, 2017 Sep 21.
Article in English | MEDLINE | ID: mdl-28954479

ABSTRACT

INTRODUCTION AND OBJECTIVES: Holding determined body postures during work is connected with muscles activity. The more forced the posture, the larger the number of muscles taking an active part in holding and stabilizing the work posture. During logging, the greatest share of awkward (forced) working postures occurs in tree felling by chainsaw. MATERIAL AND METHODS: A group of 10 experienced fellers aged 47.5±7.3 (37 - 59-years-old) was studied. Heart rate (HR) was measured during simulation of felling activity in 4 working postures: back bent forward with straight legs (stoop), back bent forward with bent legs (flexed-stoop), squat and kneeling on one knee (half-kneel). RESULTS: The lowest value of HR was noticed for squatting - 114.1 bpm, then for kneeling on one knee - 116.3 bpm. HR during felling in a standing posture with straight legs amounted to 121.5 bpm and for standing with bent legs 125.3 bpm. For all studied postures the differences in average HR values were statistically significant at p<0.01. CONCLUSIONS: A working posture during tree felling by chainsaw has influence on the level of physiological workload of an operator. Standing bent forward body postures cause higher heart response than squatting and half-kneeling.


Subject(s)
Farmers/psychology , Forestry , Adult , Emotions , Farmers/statistics & numerical data , Female , Heart Rate , Humans , Leg/physiology , Male , Middle Aged , Posture , Trees/growth & development , Workforce , Workload/psychology
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