scholarly journals The influence of weather conditions on annual height increments of Scots pine

2014 ◽  
Vol 51 (2) ◽  
pp. 143-152 ◽  
Author(s):  
Katarzyna Kaźmierczak ◽  
Bogna Zawieja
Keyword(s):  
Regression Analysis ◽  
Direct Effect ◽  
Scots Pine ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Lasso Regression ◽  
Age Classes ◽  
Main Shoot ◽  
Volume Increment

Abstract Annual height increments are a very important characteristic of Scots pine. They have a direct effect on the determination of the dendrometric properties of a stand, such as volume increment. In the present study the data concern height increments of the main shoot in selected age classes of trees (age 72 to 92 years). A relationship is determined between the values of the increments and meteorological conditions such as temperature, precipitation and sunshine. On the basis of lasso regression analysis, precipitation in the year preceding the incremental season was shown to have the greatest effect on height increments of Scots pine.

Determination of Pinussylvestris seed maturity using leachate conductivity measurements

1993 ◽  
Vol 23 (5) ◽  
pp. 864-870 ◽  
Author(s):  
Kenneth Sahlén ◽  
Svein Gjelsvik
Keyword(s):  
Regression Analysis ◽  
Scots Pine ◽  
Inorganic Phosphorus ◽  
Germination Percentage ◽  
Conductivity Measurements ◽  
Physiological Maturity ◽  
Explanatory Variables ◽  
Northern Fennoscandia ◽  
Seed Maturity

To determine whether leakage from seeds during imbibition could be used to determine maturity of Pinussylvestris L. seeds, leachate conductivity and amounts of carbohydrates and inorganic phosphorus were measured for seeds repeatedly collected from three localities in northern Fennoscandia during the ripening season. The seeds were also radiographed and tested for germination. Leachate conductivity as well as the leakage of inorganic phosphorus and carbohydrates decreased during ripening with increasing anatomical and physiological maturity until the approximate time for cessation of anatomical development. No further anatomical development occurred when leachate conductivity was lower than 6 μS•cm−1•seed−1 and the seeds were not physiologically mature as long as leachate conductivity exceeded 3–5 μS. Leachate conductivity and the amount of leached carbohydrates were 4–8 and 10–15 times higher, respectively, in nongerminable than in germinable seeds. Using regression analysis the germination percentage during ripening could be estimated with r2 between 0.96 and 0.99 with anatomical potential and leachate conductivity as explanatory variables. It is concluded that leachate conductivity measurements can be very useful for determination of Scots pine seed maturity.

scholarly journals Calibration of the Surface Renewal Method (SR) under Different Meteorological Conditions in an Avocado Orchard

Agronomy ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 730
Author(s):  
Andrés Morán ◽  
Raúl Ferreyra ◽  
Gabriel Sellés ◽  
Eduardo Salgado ◽  
Alejandro Cáceres-Mella ◽  
...  
Keyword(s):  
Energy Balance ◽  
Sensible Heat Flux ◽  
Atmospheric Stability ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Canopy Architecture ◽  
Surface Renewal ◽  
Sr Method ◽  
Renewal Method

The surface renewal method (SR) allows estimating the sensible heat flux (H) using high-frequency thermocouples. Traditionally, SR has been compared and calibrated using standard instruments such as the Eddy covariance system (EC). Calibration involves correcting H measured with SR (H’SR) by means of the calibration factor (α). However, several studies show that α is not constant and could depend on canopy architecture, measurement height, atmospheric stability, and weather conditions. In avocado orchards, there is not enough information about energy fluxes and the application of the SR method. Therefore, the objective of this study is to calibrate the SR method in a mature avocado orchard considering the effect of meteorological conditions on the determination of α. The components of the surface energy balance were measured using an EC system in a commercial avocado orchard (cv. Hass) located in the Aconcagua Valley, Valparaíso Region, Chile. To evaluate the effect of the meteorological conditions on the determination of α, the dataset was classified into nine categories based on solar radiation and wind intensity. The results show that α varies according to meteorological conditions, with significant differences for cloudy days. The use of the variable α reduced the error in estimating H, so, this methodology can be used to have a more precise approximation of the energy balance and therefore to the water requirements.

scholarly journals Regression models of volume increment percentage in the Most represented stands of coniferous tree species in Serbia

2002 ◽  
pp. 25-35 ◽  
Author(s):  
Stanisa Bankovic ◽  
Milan Medarevic ◽  
Damjan Pantic
Keyword(s):  
Scots Pine ◽  
Tree Species ◽  
Forest Inventory ◽  
Regression Models ◽  
Diameter Increment ◽  
Forest Inventories ◽  
Volume Increment ◽  
Large Scope ◽  
Coniferous Tree Species

Considering the great significance of volume increment in forestry, it is understandable that there are numerous methods of its assessment. However, all these methods have some disadvantages, either the accuracy of the obtained results, too large scope of works of forest inventory (economicity), or the restriction only to stands of certain silvicultural type. To make the method of stand volume increment more economic and simplified, we defined regression models for volume increment percentage assessment in fir, spruce, Austrian pine and Scots pine stands in Serbia. Empirical data were fitted by four regression models for each tree species. The criteria for the final selection of models for the determination of volume increment percentage were the relevant statistic parameters of regression and correlation analysis, and the degree of concordance of "real" and fitted ("table") values of volume increment percentage. The selected models for the above tree species are Fir Spruce Austrian pine Scots pine In the practical work of the assessment of current volume increment in the stand, in regular forest inventories, the method of volume increment percentage should be implemented with correction factors for the fitting of "table" (obtained by this method) values of volume increment and "real" values (obtained by the method of diameter increment), on at least 10 % of the stands of the same or similar stand class (same or similar tree species and stand form). In this way, the costs of forest inventory would be reduced, and the obtained results would range within the limits of the required accuracy .

scholarly journals South-Eastern Baltic Provenances of Scots Pine Show Heritable Weather-Growth Relationships

Forests ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1101
Author(s):  
Roberts Matisons ◽  
Volker Schneck ◽  
Diāna Jansone ◽  
Endijs Bāders ◽  
Stefānija Dubra ◽  
...  
Keyword(s):  
Scots Pine ◽  
Effective Means ◽  
Field Performance ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Moisture Regime ◽  
Morphometric Traits ◽  
South Eastern ◽  
Forest Reproductive Material ◽  
Eastern Baltic

The productivity of forests has been linked to the sensitivity of tree growth to meteorological conditions and their fluctuations, hence moderation of tree sensitivity is one of the goals for climate-smart forest management. For this, tree breeding is among the most effective means, particularly if breeding populations are supplemented with genotypes (provenances) adapted to the expected climates. Nonetheless, heritability of traits is essential for their improvement by breeding. In this study, heritability of growth sensitivity of south-eastern Baltic provenances of Scots pine differing by field performance to meteorological conditions was assessed combining methods of quantitative genetics and dendrochronology. Five parallel provenance trials within the south-eastern Baltic region were investigated. The effects of regional weather drivers of growth (moisture regime in summer, temperature regime in preceding summer and in the dormancy period) were estimated, yet their strengths differed among the provenances, indicating local specialization of metapopulations of Scots pine. The heritability of growth sensitivity to these factors ranged from low to moderate, similarly as observed for the morphometric traits within the region; however, the provenance (genetic) variation appeared to be higher. The differences in heritability of responses, however, indicated uneven adaptive significance of weather conditions. Although the estimates were based on a limited set of genotypes implying caution in the extrapolation of results, the weather-growth relationships and their heritability indicate that sensitivity of growth is a complementary trait aiding breeding of forest reproductive material best suited for future climates. Heritable weather-growth relationships also imply a high potential for forest breeding to moderate the sensitivity of the trees.

Significance of Experience, Farm Size, Quantity of Propagules and Location f or Seaweed Farmers in the Divided Island of Sebatik

2018 ◽  
Vol 9 (9) ◽  
pp. 825-832
Author(s):  
James M. Alin ◽  
◽  
Datu Razali Datu Eranza ◽  
Arsiah Bahron ◽  
◽  
...  
Keyword(s):  
Regression Analysis ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Production Function ◽  
Weather Conditions ◽  
Education Level ◽  
Farm Size ◽  
Total Production ◽  
Explanatory Factors ◽  
Douglas Production Function

Seaweed-Kappaphycus-Euchema Cottonii and Denticulum species was first cultivated at Sabah side of Sebatik in 2009. By November 2014, sixty one Sabahan seaweed farmers cultivated 122 ha or 3,050 long lines. Thirty Sabahan seaweed farmers in Kampung Pendekar (3.2 m.t dried) and 31 in Burst Point (12.5 m.t dried) produced 16 metric tonnes of dried seaweed contributed 31% to Tawau’s total production (51 m.t). The remaining 69% were from farmers in Cowie Bay that separates Sebatik from municipality of Tawau. Indonesian in Desa Setabu, Sebatik started in 2008. However, the number of Indonesian seaweed farmers, their cultivated areas and production (as well as quality) in Sebatik increased many times higher and faster than the Sabah side of Sebatik. In 2009 more than 1,401 households in Kabupaten Nunukan (including Sebatik) cultivated over 700 ha and have produced 55,098.95 and 116, 73 m.t dried seaweed in 2010 and 2011 respectively. There is a divergence in productions from farming the sea off the same island under similar weather conditions. Which of the eight explanatory factors were affecting production of seaweeds in Sebatik? Using Cobb Douglas production function, Multiple Regression analysis was conducted on 100 samples (50 Sabahan and 50 Indonesian). Results; Variable significant at α = 0.05% are Experience in farming whereas Farm size; Quantity of propagules and Location — Dummy are the variables significant at α 0.01%. Not significant are variables Fuel; Age; Number of family members involved in farming and Education level.

scholarly journals Modeling Population Spatial-Temporal Distribution Using Taxis Origin and Destination Data

2021 ◽  
Vol 13 (7) ◽  
pp. 3727
Author(s):  
Fatema Rahimi ◽  
Abolghasem Sadeghi-Niaraki ◽  
Mostafa Ghodousi ◽  
Soo-Mi Choi
Keyword(s):  
Regression Analysis ◽  
Mean Squared Error ◽  
Population Distribution ◽  
Temporal Distribution ◽  
Coefficient Of Determination ◽  
Temporal Modeling ◽  
Location Data ◽  
Time Period ◽  
Proposed Model

During dangerous circumstances, knowledge about population distribution is essential for urban infrastructure architecture, policy-making, and urban planning with the best Spatial-temporal resolution. The spatial-temporal modeling of the population distribution of the case study was investigated in the present study. In this regard, the number of generated trips and absorbed trips using the taxis pick-up and drop-off location data was calculated first, and the census population was then allocated to each neighborhood. Finally, the Spatial-temporal distribution of the population was calculated using the developed model. In order to evaluate the model, a regression analysis between the census population and the predicted population for the time period between 21:00 to 23:00 was used. Based on the calculation of the number of generated and the absorbed trips, it showed a different spatial distribution for different hours in one day. The spatial pattern of the population distribution during the day was different from the population distribution during the night. The coefficient of determination of the regression analysis for the model (R2) was 0.9998, and the mean squared error was 10.78. The regression analysis showed that the model works well for the nighttime population at the neighborhood level, so the proposed model will be suitable for the day time population.

scholarly journals Non-Destructive Micromagnetic Determination of Hardness and Case Hardening Depth Using Linear Regression Analysis and Artificial Neural Networks

Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 18
Author(s):  
Rahel Jedamski ◽  
Jérémy Epp
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Regression Analysis ◽  
Artificial Neural Networks ◽  
Linear Regression ◽  
Linear Regression Analysis ◽  
Case Hardening ◽  
Artificial Neural ◽  
Non Destructive

Non-destructive determination of workpiece properties after heat treatment is of great interest in the context of quality control in production but also for prevention of damage in subsequent grinding process. Micromagnetic methods offer good possibilities, but must first be calibrated with reference analyses on known states. This work compares the accuracy and reliability of different calibration methods for non-destructive evaluation of carburizing depth and surface hardness of carburized steel. Linear regression analysis is used in comparison with new methods based on artificial neural networks. The comparison shows a slight advantage of neural network method and potential for further optimization of both approaches. The quality of the results can be influenced, among others, by the number of teaching steps for the neural network, whereas more teaching steps does not always lead to an improvement of accuracy for conditions not included in the initial calibration.

scholarly journals The landscape of gene co-expression modules correlating with prognostic genetic abnormalities in AML

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Chao Guo ◽  
Ya-yue Gao ◽  
Qian-qian Ju ◽  
Chun-xia Zhang ◽  
Ming Gong ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Prediction Model ◽  
Hox Genes ◽  
Expression Profiles ◽  
Penalized Regression ◽  
Diagnostic Utility ◽  
Lasso Regression ◽  
Hub Genes ◽  
Npm1 Mutation ◽  
Genetic Abnormalities

Abstract Background The heterogenous cytogenetic and molecular variations were harbored by AML patients, some of which are related with AML pathogenesis and clinical outcomes. We aimed to uncover the intrinsic expression profiles correlating with prognostic genetic abnormalities by WGCNA. Methods We downloaded the clinical and expression dataset from BeatAML, TCGA and GEO database. Using R (version 4.0.2) and ‘WGCNA’ package, the co-expression modules correlating with the ELN2017 prognostic markers were identified (R2 ≥ 0.4, p < 0.01). ORA detected the enriched pathways for the key co-expression modules. The patients in TCGA cohort were randomly assigned into the training set (50%) and testing set (50%). The LASSO penalized regression analysis was employed to build the prediction model, fitting OS to the expression level of hub genes by ‘glmnet’ package. Then the testing and 2 independent validation sets (GSE12417 and GSE37642) were used to validate the diagnostic utility and accuracy of the model. Results A total of 37 gene co-expression modules and 973 hub genes were identified for the BeatAML cohort. We found that 3 modules were significantly correlated with genetic markers (the ‘lightyellow’ module for NPM1 mutation, the ‘saddlebrown’ module for RUNX1 mutation, the ‘lightgreen’ module for TP53 mutation). ORA revealed that the ‘lightyellow’ module was mainly enriched in DNA-binding transcription factor activity and activation of HOX genes. The ‘saddlebrown’ module was enriched in immune response process. And the ‘lightgreen’ module was predominantly enriched in mitosis cell cycle process. The LASSO- regression analysis identified 6 genes (NFKB2, NEK9, HOXA7, APRC5L, FAM30A and LOC105371592) with non-zero coefficients. The risk score generated from the 6-gene model, was associated with ELN2017 risk stratification, relapsed disease, and prior MDS history. The 5-year AUC for the model was 0.822 and 0.824 in the training and testing sets, respectively. Moreover, the diagnostic utility of the model was robust when it was employed in 2 validation sets (5-year AUC 0.743–0.79). Conclusions We established the co-expression network signature correlated with the ELN2017 recommended prognostic genetic abnormalities in AML. The 6-gene prediction model for AML survival was developed and validated by multiple datasets.

scholarly journals Potential Fertilization Capacity of Two Grapevine Varieties: Effects on Agricultural Production in Designation of Origin Areas in the Northwestern Iberian Peninsula

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 961
Author(s):  
J. Antonio Cortiñas Rodríguez ◽  
María Fernández-González ◽  
Estefanía González-Fernández ◽  
Rosa A. Vázquez-Ruiz ◽  
F. Javier Rodríguez-Rajo ◽  
...  
Keyword(s):  
Airborne Pollen ◽  
Germination Rate ◽  
Pollen Viability ◽  
Weather Conditions ◽  
Triphenyl Tetrazolium Chloride ◽  
Tetrazolium Chloride ◽  
The Mean ◽  
Study Sites ◽  
Fertilization Capacity

In the present study, we analyzed the main parameters related with the potential fertilization ability of two grapevine varieties, Godello and Mencía, during the years 2017 and 2018. The research was carried out in two vineyards of the Galician winegrowing Designation of Origin areas of Ribeiro and Ribeira Sacra. Ten vines of each variety were selected for bunch and flower counting, pollen calculations, pollen viability studies by means of aceto-carmine (AC) stain and 2, 3, 5-triphenyl tetrazolium chloride (TTC) methods, and the determination of their germination rate. In all vineyards the 50% fruitset was reached, except for Godello in Cenlle during 2017. The mean coulure value was higher for Godello (40.5%) than for Mencía (31%). Analyzing the pollen production per plant and airborne pollen levels, we observed important discordances between them, which can be due to the influence of weather conditions and be related with self-pollination processes. We found important differences on pollen viability depending on the applied method and variety, with higher values for the AC method than the TTC for both varieties in all study plots, and higher values for Mencía variety than Godello. Regarding germination rates, we observed a marked reduction in 2017 with respect to 2018, in all study sites and for both varieties. The analyzed parameters were useful to explain the different productive abilities of Godello and Mencía varieties in the two studied bioclimatic regions of Ribeiro and Ribeira Sacra.

scholarly journals Influence of Meteorological Conditions and Aerosol Properties on the COVID-19 Contamination of the Population in Coastal and Continental Areas in France: Study of Offshore and Onshore Winds

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 523
Author(s):  
Jacques Piazzola ◽  
William Bruch ◽  
Christelle Desnues ◽  
Philippe Parent ◽  
Christophe Yohia ◽  
...  
Keyword(s):  
Atmospheric Transport ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Sea Spray ◽  
Atmospheric Conditions ◽  
Virus Transport ◽  
Virus Propagation ◽  
Viral Particles ◽  
The Social ◽  
Aerosol Properties

Human behaviors probably represent the most important causes of the SARS-Cov-2 virus propagation. However, the role of virus transport by aerosols—and therefore the influence of atmospheric conditions (temperature, humidity, type and concentration of aerosols)—on the spread of the epidemic remains an open and still debated question. This work aims to study whether or not the meteorological conditions related to the different aerosol properties in continental and coastal urbanized areas might influence the atmospheric transport of the SARS-Cov-2 virus. Our analysis focuses on the lockdown period to reduce the differences in the social behavior and highlight those of the weather conditions. As an example, we investigated the contamination cases during March 2020 in two specific French areas located in both continental and coastal areas with regard to the meteorological conditions and the corresponding aerosol properties, the optical depth (AOD) and the Angstrom exponent provided by the AERONET network. The results show that the analysis of aerosol ground-based data can be of interest to assess a virus survey. We found that moderate to strong onshore winds occurring in coastal regions and inducing humid environment and large sea-spray production episodes coincides with smaller COVID-19 contamination rates. We assume that the coagulation of SARS-Cov-2 viral particles with hygroscopic salty sea-spray aerosols might tend to inhibit its viral infectivity via possible reaction with NaCl, especially in high relative humidity environments typical of maritime sites.

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