Leaf specific mass confounds leaf density and thickness

Oecologia ◽  
1991 ◽  
Vol 88 (4) ◽  
pp. 486-493 ◽  
Author(s):  
E. T. F. Witkowski ◽  
Byron B. Lamont
Keyword(s):  
Specific Mass ◽  
Leaf Density ◽  
Leaf Specific Mass

scholarly journals Gas exchange and leaf specific mass of different foliar cohorts of the wintergreen shrub Aristotelia chilensis (Mol.) stuntz (Eleocarpaceae) fifteen days before the flowering and the fall of the old cohort

2001 ◽  
Vol 44 (3) ◽  
pp. 277-282 ◽  
Author(s):  
Carlos Henrique B. A. Prado ◽  
María A. Damascos
Keyword(s):  
Net Photosynthesis ◽  
Dry Mass ◽  
High Irradiance ◽  
Specific Mass ◽  
Mean Values ◽  
Specific Leaf Mass ◽  
Use Efficiency ◽  
Aristotelia Chilensis ◽  
In The Beginning ◽  
Leaf Specific Mass

In the beginning of the spring Aristotelia chilensis sheds the old cohort, forms a new one and flowers. Fifteen days before the flowering and the fall we measured net photosynthesis (A), transpiration (E), water use efficiency (WUE), specific leaf mass (SLM) and area and mass of leaves per branch in old and new cohorts. Under low irradiance the old cohort exhibited higher mean values of A and WUE on area bases (P<0.05). Under high irradiance A and WUE on mass bases were higher in new cohort due to its lower SLM (42.10 gm-2) in relation to old cohort (79.53 gm-2). Because old cohort showed 3.7 times more dry mass per branch it was able to counterbalance its lower performance on mass bases. It was concluded that old cohort was an important source of carbon during two powerful sink processes in the beginning of the spring: new leaves cohort construction and flowering.

scholarly journals Silicon sources for studies of rice plants in nutrient solutions

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
Luiz Antônio Zanão Júnior ◽  
Victor Hugo Alvarez V. ◽  
Renildes Lúcio Ferreira Fontes ◽  
Maristela Pereira Carvalho-Zanão ◽  
Natalia Pereira
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Sodium Metasilicate ◽  
Dry Matter Yield ◽  
Specific Mass ◽  
Rice Plants ◽  
Significant Difference ◽  
Leaves And Roots ◽  
Leaf Specific Mass ◽  
Nutrient Solutions

The objective of this work was to evaluate the effects of various Si sources currently used in studies of Si doses in nutrient solutions on dry matter yield and the accumulation of nutrients and Si in rice plants. Treatments of rice plants with three sources of Si (monossilicic acid, sodium metasilicate, potassium metasilicate) and a treatment without Si were allocated in a randomized block design with ten replications. After 39 days in the nutrient solution, the following traits were evaluated: leaf area, leaf specific mass, dry matter yield of roots and shoots, and levels of K, Na, and Si in leaves and roots. Si increased leaf area, leaf specific mass, and dry matter yield of shoots and roots regardless of the Si source. Levels of Si in leaves and roots were significantly higher in relation to the control treatment but no significant difference among Si sources was identified. It was also observed that K and Na were adequately balanced across the treatments. Thus, a cheaper and easier to obtain Si source, such as sodium metasilicate and potassium metasilicate, may be chosen to carry out studies of Si additions to nutrient solutions.

Morphometry of leaf and shoot variables to assess aboveground biomass structure and carbon sequestration by different varieties of white mulberry (Morus alba L.)

2021 ◽  
Author(s):  
Ghulam Ali Bajwa ◽  
Muhammad Umair ◽  
Yasir Nawab ◽  
Zahid Rizwan
Keyword(s):  
Carbon Sequestration ◽  
Leaf Area ◽  
Aboveground Biomass ◽  
Shoot Density ◽  
Morus Alba ◽  
Coefficient Of Determination ◽  
Equivalent Diameter ◽  
Organic Carbon Content ◽  
Reasonable Accuracy ◽  
Leaf Density

AbstractMulberry is economically important and can also play a pivotal role in mitigating greenhouse gases. Leaf and shoot traits were measured for Morus alba var. Kanmasi, M. alba var. Karyansuban, M. alba var. Latifolia, and M. alba var. PFI-1 to assess aboveground biomass (AGB) and carbon sequestration. Variety-specific and multivariety allometric AGB models were developed using the equivalent diameter at breast height (EDBH) and plant height (H). The complete-harvest method was used to measure leaf and shoot traits and biomass, and the ash method was used to measure organic carbon content. The results showed significant (p < 0.01) varietal differences in leaf and shoot traits, AGB and carbon sequestration. PFI-1 variety had the greatest leaf density (mean ± SE: 1828.3 ± 0.3 leaves tree−1), Karyansuban had the largest mean leaf area (185.94 ± 8.95 cm2). A diminishing return was found between leaf area and leaf density. Latifolia had the highest shoot density per tree (46.6 ± 1.83 shoots tree−1), total shoot length (264.1 ± 2.32 m), dry biomass (16.69 ± 0.58 kg tree−1), carbon sequestration (9.99 ± 0.32 kg tree−1) and CO2 mitigation (36.67 ± 1.16 kg). The variety-specific AGB models b(EDBH) and b(EDBH)2 showed good fit and reasonable accuracy with a coefficient of determination (R2) = 0.98–0.99, standard error of estimates (SEE) = 0.1125–0.3130 and root mean square error (RMSE) = 0.1084–0.3017. The multivariety models bln(EDBH) and (EDBH)0.756 showed good-fitness and accuracy with R2 = 0.85–0.86, SEE = 1.6231–1.6445 and RMSE = 1.609–1.630. On the basis of these findings, variety Latifolia has good potential for biomass production, and allometric equations based on EDBH can be used to estimate AGB with a reasonable accuracy.

scholarly journals Health and sustainability of glaciers in High Mountain Asia

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Evan Miles ◽  
Michael McCarthy ◽  
Amaury Dehecq ◽  
Marin Kneib ◽  
Stefan Fugger ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Field Measurements ◽  
Tien Shan ◽  
High Mountain ◽  
Specific Mass ◽  
Ice Flow ◽  
Ice Volume ◽  
Mass Redistribution ◽  
Glacier Ablation

AbstractGlaciers in High Mountain Asia generate meltwater that supports the water needs of 250 million people, but current knowledge of annual accumulation and ablation is limited to sparse field measurements biased in location and glacier size. Here, we present altitudinally-resolved specific mass balances (surface, internal, and basal combined) for 5527 glaciers in High Mountain Asia for 2000–2016, derived by correcting observed glacier thinning patterns for mass redistribution due to ice flow. We find that 41% of glaciers accumulated mass over less than 20% of their area, and only 60% ± 10% of regional annual ablation was compensated by accumulation. Even without 21st century warming, 21% ± 1% of ice volume will be lost by 2100 due to current climatic-geometric imbalance, representing a reduction in glacier ablation into rivers of 28% ± 1%. The ablation of glaciers in the Himalayas and Tien Shan was mostly unsustainable and ice volume in these regions will reduce by at least 30% by 2100. The most important and vulnerable glacier-fed river basins (Amu Darya, Indus, Syr Darya, Tarim Interior) were supplied with >50% sustainable glacier ablation but will see long-term reductions in ice mass and glacier meltwater supply regardless of the Karakoram Anomaly.

scholarly journals Data-Independent Acquisition for the Quantification and Identification of Metabolites in Plasma

Metabolites ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 514
Author(s):  
Tom van der Laan ◽  
Isabelle Boom ◽  
Joshua Maliepaard ◽  
Anne-Charlotte Dubbelman ◽  
Amy C. Harms ◽  
...  
Keyword(s):  
Mass Spectra ◽  
Mass Range ◽  
Correct Identification ◽  
Hydrophilic Interaction ◽  
Specific Mass ◽  
Structural Isomers ◽  
Data Independent Acquisition ◽  
Targeted Analysis ◽  
Theoretical Mass ◽  
Accurate Quantification

A popular fragmentation technique for non-targeted analysis is called data-independent acquisition (DIA), because it provides fragmentation data for all analytes in a specific mass range. In this work, we demonstrated the strengths and weaknesses of DIA. Two types of chromatography (fractionation/3 min and hydrophilic interaction liquid chromatography (HILIC)/18 min) and three DIA protocols (variable sequential window acquisition of all theoretical mass spectra (SWATH), fixed SWATH and MSALL) were used to evaluate the performance of DIA. Our results show that fast chromatography and MSALL often results in product ion overlap and complex MS/MS spectra, which reduces the quantitative and qualitative power of these DIA protocols. The combination of SWATH and HILIC allowed for the correct identification of 20 metabolites using the NIST library. After SWATH window customization (i.e., variable SWATH), we were able to quantify ten structural isomers with a mean accuracy of 103% (91–113%). The robustness of the variable SWATH and HILIC method was demonstrated by the accurate quantification of these structural isomers in 10 highly diverse blood samples. Since the combination of variable SWATH and HILIC results in good quantitative and qualitative fragmentation data, it is promising for both targeted and untargeted platforms. This should decrease the number of platforms needed in metabolomics and increase the value of a single analysis.

Fish larvae settling in seagrass: Effects of leaf density and an epiphytic alga

1991 ◽  
Vol 16 (3) ◽  
pp. 289-293 ◽  
Author(s):  
D. G. WORTHINGTON ◽  
M. WESTOBY ◽  
J. D. BELL
Keyword(s):  
Fish Larvae ◽  
Epiphytic Alga ◽  
Leaf Density

Topology-Optimized Intermediate Casing of Aero Engine and Comparative Evaluation of Titanium and Composite Architecture in Terms of Load Capacity and Weight Reduction

2008 ◽  
Author(s):  
Markus Kober ◽  
Olaf Lenk ◽  
Thomas Klauke ◽  
Arnold Ku¨hhorn
Keyword(s):  
Topology Optimization ◽  
Failure Criterion ◽  
Load Capacity ◽  
Specific Power ◽  
Fracture Plane ◽  
Fiber Reinforced ◽  
Specific Mass ◽  
Fiber Fracture ◽  
Damage And Fracture ◽  
Aero Engine

From Aero Engines of the future it is demanded to provide more power, while the fuel consumption and the mass should decrease. In order to reach the goal of an increasing specific power or a decreasing specific mass, respectively, structural optimization methods, like the topology optimization, find their way into the design process to a greater extent. Additionally one is going to consider more and more fiber reinforced composites as a substitute for titanium alloys in the “cold” structure of the engine. Composite materials offer significant advantages especially concerning the specific mass and the adjustability of their stiffness properties. Unfortunately it is very difficult to predict damage and fracture of such orthotropic materials. The presentation will show the results of a topology optimization of the titanium intermediate-casing of a Rolls-Royce aero engine. Further on the material of the casing will be substituted by a carbon fiber reinforced composite. The fiber orientations and layer thicknesses of the composite are optimized under certain strength constraints, which are described by a modern fracture plane based failure criterion (NASA LaRC04 criterion [6]). Such a failure criterion has a lot of advantages compared to classical ones like Tsai-Hill, Tsai-Wu, ..., which e.g. do not distinguish between fiber and inter-fiber fracture and are therefore not able to predict the type of inter-fiber fracture. Finally the results of the optimization with the current material titanium will be compared to the results of the composite-made intermediate casing in terms of their load capacity and weight.

Sign in / Sign up

Export Citation Format

Share Document