Leaf and environmental parameters influencing transpiration: Theory and field measurements

Oecologia ◽  
1980 ◽  
Vol 46 (3) ◽  
pp. 308-313 ◽  
Author(s):  
W. K. Smith ◽  
G. N. Geller
Keyword(s):  
Environmental Parameters ◽  
Field Measurements

scholarly journals FIELD MEASUREMENTS AND SWASH PARAMETERIZATION ON BEACHES

2018 ◽  
pp. 23
Author(s):  
Paula Gomes Da Silva ◽  
Raúl Medina ◽  
Mauricio González ◽  
Roland Garnier
Keyword(s):  
Environmental Parameters ◽  
Field Measurements ◽  
Wave Runup ◽  
Wave Processes ◽  
Site Specific ◽  
Erosion Risk ◽  
Sediment Size ◽  
Water Edge ◽  
Offshore Wave ◽  
Empirical Approaches

The wave runup, defined as the vertical oscillation of the water edge at the coast, is commonly used as criterion for coastal design projects and flooding/erosion risk analysis. Due to the complexity of nearshore wave processes, most runup studies are based on empirical approaches which directly relate these oscillations to the beach and offshore wave characteristics. However, there is still considerable debate about just how runup is related to these environmental parameters, as well as about the range of application of empirical models due to site specific conditions. Recent works emphasized the importance of including site specific conditions to reduce the scatter in available parameterizations. Parameters related to beach characteristics like the sediment size, the amount of reflection, wave spectral shape and morphodynamic beach state may improve runup predictions (Poate et al., 2016, Guza and Feddersen, 2012).

scholarly journals Seasonal Variation of Soil Respiration in the Mongolian Oak (Quercus mongolica Fisch. Ex Ledeb.) Forests at the Cool Temperate Zone in Korea

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 984
Author(s):  
Gyung Soon Kim ◽  
Seung Jin Joo ◽  
Chang Seok Lee
Keyword(s):  
Soil Respiration ◽  
Environmental Parameters ◽  
Field Measurements ◽  
Temperate Zone ◽  
Short Time Scale ◽  
Strongly Correlated ◽  
Quercus Mongolica ◽  
Cool Temperate ◽  
Mongolian Oak ◽  
Short Time

To investigate the variation in seasonal soil respiration (SR) as a function of soil temperature (Ts) and soil water content (SWC) in Mongolian oak (Quercus mongolica) forests in urban (Mt. Nam) and well-reserved (Mt. Jeombong) areas in South Korea, we conducted continuous field measurements of SR and other environmental parameters (Ts and SWC) using an automated chamber system. Overall, the SR rates in both stands were strongly correlated with the Ts variable during all seasons. However, abrupt fluctuations in SR were significantly related to episodic increases in SWC on a short time scale during the growing season. The integrated optimal regression models for SR using Ts at a depth of 5 cm and SWC at a depth of 15 cm yielded the following: the SR rate in Mt. Nam = SR(Ts) + ΔSR(Ts) = 104.87 exp(0.1108Ts) − 10.09(SWC)2 + 604.2(SWC) − 8627.7 for Ts ≥ 0 °C, and the SR rate in Mt. Jeombong = SR(Ts) + ΔSR(Ts) = 95.608 exp(0.1304Ts) − 33.086(SWC)2 + 1949.2(SWC) − 28499 for Ts ≥ 0 °C. In both cases, SR = 0 for Ts < 0 °C. As per these equations, the estimated annual total SRs were 1339.4 g C m−2 for Mt. Nam and 1003.0 g C m−2 for Mt. Jeombong. These values were quite similar to the measured values in field. Our results demonstrate that the improved empirical equation is an effective tool for estimating and predicting SR variability and provide evidence that the SR of Q. mongolica forests in the cool temperate zone of Korean Peninsula depends on Ts and SWC variables.

The effect of climate on the photosynthesis of Picea mariana at the subarctic tree line. 1. Field measurements

1975 ◽  
Vol 53 (7) ◽  
pp. 604-620 ◽  
Author(s):  
T. Vowinckel ◽  
W. C. Oechel ◽  
W. G. Boll
Keyword(s):  
Picea Mariana ◽  
Dark Respiration ◽  
Environmental Parameters ◽  
Field Measurements ◽  
Dry Weight ◽  
Gas Analysis ◽  
Tree Line ◽  
Stevenson Screen ◽  
Analysis System ◽  
June July

Field measurements of the diurnal rates of photosynthesis of Picea mariana, the dominant tree species at the subarctic tree line, were made during the summers of 1972 and 1973 at Schefferville, Quebec (latitude 55° N). All relevant plant physiological and environmental parameters were also monitored. Photosynthesis was measured with an open gas analysis system with temperature-controlled cuvettes. Maximum daily rates were 2.0–3.5 mg CO2 g−1 dry weight h−1. Daily totals were between 15 and 30 mg CO2 g−1 dry weight. Temperature was unimportant in affecting daily photosynthesis totals during the summer months. The photosynthesis vs. needle temperature curve had an optimum of 15C. Dark respiration rates were 0.2–0.4 mg CO2 g−1 dry weight h−1 at 15C. The photosynthesis vs. light intensity curve was saturated at 0.8 ly min−1 (1.0 μE cm−2 s−1 PhAR.). As a result, heavy cloud cover considerably reduced daily photosynthesis. No seasonal variations in photosynthesis over June, July, and August were observed. No differences in maximum rates occurred between the three experimental sites. Needle temperatures within the cuvettes were 2–4C above air temperature under full sunlight (1.2 ly min−1). Needle temperatures under natural conditions were up to 7C above Stevenson screen temperatures and fluctuated rapidly with changes in turbulence.

IN SITU MEASUREMENT OF DISSOLVED MATERIALS AS AN INDICATOR OF ORGANIC TERRAIN TYPE

1973 ◽  
Vol 53 (2) ◽  
pp. 231-236 ◽  
Author(s):  
M. E. WALMSLEY ◽  
L. M. LAVKULICH
Keyword(s):  
Ph Value ◽  
Environmental Parameters ◽  
Field Measurements ◽  
Oxygen Electrode ◽  
Natural Systems ◽  
Terrain Type ◽  
Ion Activity ◽  
Different Types ◽  
Dissolved Load

Portable equipment has been used to measure selected environmental parameters in situ. A battery-operated potentiometer used in conjunction with several specific ion electrodes, a platinum redox electrode, and a combination pH electrode were used to obtain ion activity, pH, and Eh measurements of natural systems. In addition, dissolved oxygen concentration was measured using an oxygen electrode and battery-operated meter. Results from the analysis of several streams are presented to illustrate the application of the technique to field measurements of streams as an indicator of environmental disturbance. Information collected also allowed for the differentiation of different types of organic terrain based on the dissolved load of the saturated organic materials. The terrain type referred to as fen had a higher activity of Na, Cl, and Ca, a higher pH value, and a lower concentration of oxygen than the bog terrain type. These results are explained with reference to organic terrain morphology and the distribution of permafrost in the study area.

Environmental parameters and analysis of crowd flow in an academic building of a university

2019 ◽  
Vol 30 (1) ◽  
pp. 39-55 ◽  
Author(s):  
Wenjun Lei ◽  
Chuanmin Tai ◽  
Chuanliang Rong ◽  
Xinye Qi ◽  
Linhua Zhang ◽  
...  
Keyword(s):  
Environmental Parameters ◽  
Field Measurements ◽  
Spatial Separation ◽  
Test Results ◽  
Universities And Colleges ◽  
Physical Separation ◽  
Average Speed ◽  
Academic Buildings ◽  
Academic Building

Academic buildings are the main gathering places in universities and colleges. The crowd flow could cause a change in environmental parameters of buildings. In other words, the change in environmental parameters in buildings can be somewhat reflective of the crowd flow. Therefore, field measurements of the crowd flow and environmental parameters in an academic building at a university were conducted in this study. During the periods of 7:30–8:00 and 13:20–13:50, the average speed of the crowd was the highest, which was about 1.2 m/s; the CO2 concentration was low, which was about 750 ppm. In the periods of 9:20–9:50 and 15:10–15:40, the average speed of people walking in the opposite directions was the lowest, which is 0.42 m/s; however, the CO2 concentration could reach 1800 ppm. Test results showed that the variations of CO2 concentrations were inversely related to the average speed of the crowd in the evacuation passage, except for the periods of 7:30–8:00 and 13:20–13:50. Spatial separation and physical separation could be used in the management of personnel flow in the academic building. The results may provide reference for the management of the crowd flow in similar academic buildings of other universities.

scholarly journals Instrumental Study of the Health Status of Picea abies and Pinus mugo (Turra) and Their Relation to Environmental Parameters in the Eastern Alps

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 716
Author(s):  
Dominika Falvai ◽  
Dénes Saláta ◽  
Tivadar Baltazár ◽  
Szilárd Czóbel
Keyword(s):  
Health Status ◽  
Picea Abies ◽  
Lower Limit ◽  
Environmental Parameters ◽  
Field Measurements ◽  
Eastern Alps ◽  
Pinus Mugo ◽  
Mountainous Regions ◽  
Significant Temperature ◽  
The Alps

Many climatic models predict significant temperature rises in mountainous regions, which may influence the distribution of montane species. Thermophilization observed or predicted in mountainous areas to date may accelerate the shift of forest-forming trees to higher areas. Our aim was to detect how the health status of Norway spruce (Picea abies [L.] Karst) and dwarf mountain pine (Pinus mugo (Turra)) changes along an altitudinal transect, and to what extent the health status of trees depends on the studied environmental variables. Field measurements were performed in the Alps with an acoustic tomograph, which is able to determine the extent and exact location of rotten parts without damage. In the case of P. abies, the stands are currently considered to be the healthiest between 1000 and 1500 m, while they show the greatest deterioration near the lower limit of their distribution. At the lower limit of the vertical distribution of the species, a retreat of 50–100 m is expected. We observed a different trend in the relationship between deterioration values and altitude depending on the extent of the P. mugo belt. It seems the extent and speed of the upper movement may be different in different mountains, depending on environmental parameters.

THE IMPACT OF THE INDOOR ENVIRONMENTAL QUALITY ON STUDENTS’ PERFORMANCE

2021 ◽  
Author(s):  
Tania Rus ◽  
Dorin Beu ◽  
Calin Ciugudeanu
Keyword(s):  
Carbon Dioxide ◽  
Environmental Quality ◽  
Current Knowledge ◽  
Carbon Dioxide Concentration ◽  
Environmental Parameters ◽  
Field Measurements ◽  
Well Being ◽  
Indoor Environmental Quality ◽  
Key Factor ◽  
The Impact

"The indoor environment quality is a key factor in people's lives, which directly affects their comfort, performance, health and well-being. The main factors that contribute to the indoor environmental quality are thermal comfort, air and lighting quality and acoustics. This study aims to extend the current knowledge on the impact of IEQ on students’ performance. Field measurements on environmental factors were performed in two similar classrooms, with the same number of students engaged in a written examination. Compliance of the indoor environmental parameters with the current standards regulations was performed. Students’ performance was quantified by their exam grades. The results of the field measurements show that, in both classrooms, the acoustics and air quality do not fulfil the standard regulations, especially in the case of carbon dioxide concentration which exceeds a lot the threshold limit of 1000 ppm. The outcomes of the study also reveal that in the classroom where the concentration of carbon dioxide is higher, the students scored lower grades, therefore we can conclude that indoor environmental quality has an impact on students’ performance."

Geophysics - Field Measurements

1987 ◽  
Keyword(s):  
Field Measurements

HUBUNGAN KEPADATAN BIVALVIA DENGAN PARAMETER LINGKUNGAN DI PESISIR TANJUNG PURA KABUPATEN BANGKA TENGAH

2020 ◽  
Vol 13 (2) ◽  
pp. 112-121
Author(s):  
Sudiyar . ◽  
Okto Supratman ◽  
Indra Ambalika Syari
Keyword(s):  
Negative Impact ◽  
Principal Component ◽  
Environmental Parameters ◽  
Data Retrieval ◽  
Distribution Patterns ◽  
Random System ◽  
System Method ◽  
Relationship Of ◽  
The Relationship ◽  
Anadara Granosa

The destructive fishing feared will give a negative impact on the survival of this organism. This study aims to analyze the density of bivalves, distribution patterns, and to analyze the relationship of bivalves with environmental parameters in Tanjung Pura village. This research was conducted in March 2019. The systematic random system method was used for collecting data of bivalves. The collecting Data retrieval divided into five research stasions. The results obtained 6 types of bivalves from 3 families and the total is 115 individuals. The highest bivalve density is 4.56 ind / m², and the lowest bivalves are located at station 2,1.56 ind / m²,  The pattern of bivalve distribution in the Coastal of Tanjung Pura Village is grouping. The results of principal component analysis (PCA) showed that Anadara granosa species was positively correlated with TSS r = 0.890, Dosinia contusa, Anomalocardia squamosa, Mererix meretrix, Placamen isabellina, and Tellinella spengleri were positively correlated with currents r = 0.933.

79. Comparison of Benzene-Specific Field Measurements at Oil Refineries

1999 ◽  
Author(s):  
W.R. Haag ◽  
P. Owens ◽  
D. Mayszak ◽  
J. Katona ◽  
B. Mangilin ◽  
...  
Keyword(s):  
Field Measurements ◽  
Oil Refineries ◽  
Specific Field
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