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Stand-level biomass models for predicting C stock for the main Spanish pine species 被引量:4
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作者 Ana Aguirre Miren del Río +1 位作者 Ricardo Ruiz-Peinado Sonia Condés 《Forest Ecosystems》 SCIE CSCD 2021年第2期387-402,共16页
Background:National and international institutions periodically demand information on forest indicators that are used for global reporting.Among other aspects,the carbon accumulated in the biomass of forest species mu... Background:National and international institutions periodically demand information on forest indicators that are used for global reporting.Among other aspects,the carbon accumulated in the biomass of forest species must be reported.For this purpose,one of the main sources of data is the National Forest Inventory(NFI),which together with statistical empirical approaches and updating procedures can even allow annual estimates of the requested indicators.Methods:Stand level biomass models,relating the dry weight of the biomass with the stand volume were developed for the five main pine species in the Iberian Peninsula(Pinus sylvestris,Pinus pinea,Pinus halepensis,Pinus nigra and Pinus pinaster).The dependence of the model on aridity and/or mean tree size was explored,as well as the importance of including the stand form factor to correct model bias.Furthermore,the capability of the models to estimate forest carbon stocks,updated for a given year,was also analysed.Results:The strong relationship between stand dry weight biomass and stand volume was modulated by the mean tree size,although the effect varied among the five pine species.Site humidity,measured using the Martonne aridity index,increased the biomass for a given volume in the cases of Pinus sylvestris,Pinus halepensis and Pinus nigra.Models that consider both mean tree size and stand form factor were more accurate and less biased than those that do not.The models developed allow carbon stocks in the main Iberian Peninsula pine forests to be estimated at stand level with biases of less than 0.2 Mg·ha^(-1).Conclusions:The results of this study reveal the importance of considering variables related with environmental conditions and stand structure when developing stand dry weight biomass models.The described methodology together with the models developed provide a precise tool that can be used for quantifying biomass and carbon stored in the Spanish pine forests in specific years when no field data are available. 展开更多
关键词 Martonne aridity index Dry weight biomass Carbon stock National Forest Inventory Peninsular pine forest Biomass expansion factor
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Relativistic Quantum Mechanical Condition for Expansion of the Universe
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作者 Nishant Kumar Sharma 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期1049-1088,共40页
In this manuscript, we will discuss about the quantum mechanical system for the movement of non-intractable particle, non-intractable particle which attends every mass state in the universe, the form of a non-intracta... In this manuscript, we will discuss about the quantum mechanical system for the movement of non-intractable particle, non-intractable particle which attends every mass state in the universe, the form of a non-intractable particle is <i>n</i> = -<i>m</i>, this manuscript defines the stable cross system for the movement of <i>n</i>-<i>i</i> particles and elementary particles with a perfect black body at centre with proofs of picture of super massive black hole, the linear hamiltonian of the cross quantum mechanical system and with this, it’s co-related matrixes, then by the use of cross system of Non-Intractable Particles defining a new right angel theorem. Then the new black body relation free from plank constant depends on non interactive mechanics and <i>m</i>, which has already mentioned in non-interactive mechanics and it’s relation with galaxies. The unique property of cross system is that it is surrounded by the energy of 10e + e always, and at last the relation between zero point energy and dark energy. 展开更多
关键词 Riemannian Geometry Euclidean Geometry Right Angel Theorem factors for the Expansion of Universe Black Body Radiation Cosmic Form of the Nishant Effect
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