scholarly journals Nonlinear growth dynamics of date palms responding to environmental parameters

Food Research ◽  
2020 ◽  
Vol 4 (S6) ◽  
pp. 60-63
Author(s):  
E.J. Magero ◽  
K. Unami ◽  
O. Mohawesh ◽  
M. Yamaguchi ◽  
M. Fujihara
Keyword(s):  
Solar Radiation ◽  
Environmental Conditions ◽  
Field Experiments ◽  
Growth Dynamics ◽  
Environmental Parameters ◽  
Dynamical Response ◽  
Palm Tree ◽  
Soil Matric Potential ◽  
Matric Potential ◽  
Date Palms

Scientific analysis of plant growth helps in improving the efficiency of cultivation practices through optimization of their environmental conditions. The ultimate aim of this research was to derive an optimal policy for better growth of date palms by considering its dynamical response to environmental parameters such as solar radiation, soil moisture, and temperature. Field experiments were conducted at an irrigation scheme located in the Jordan Rift Valley. A drip irrigation system is installed to water ten trees of date palms either with fresh or saline water depending on the soil matric potential. The circumference of the trunk of a tree was measured using a dendrometer at 30 mins interval and recorded in a data logger. Environmental parameters including the soil matric potential, solar radiation, and soil temperature were also logged every 30 mins. This study focused on determining a nonlinear model representing the growth dynamics of the date palm tree responding to those environmental parameters. The linear regression was applied to estimate the kernel coefficients of discrete Volterra series modeling the time series. The non-linearity of the model is expected to explain diurnal shrinkage and swelling of the tree trunk under different environmental conditions.

Response of Gas Exchange in Jointed Goatgrass (Aegilops cylindrica) to Environmental Conditions

Weed Science ◽  
1989 ◽  
Vol 37 (4) ◽  
pp. 562-569 ◽  
Author(s):  
David R. Gealy
Keyword(s):  
Soil Moisture ◽  
Gas Exchange ◽  
Environmental Conditions ◽  
Dark Respiration ◽  
Net Photosynthesis ◽  
Soil Matric Potential ◽  
Dark Respiration Rate ◽  
Matric Potential ◽  
Aegilops Cylindrica ◽  
Jointed Goatgrass

Gas exchange of jointed goatgrass leaves was affected by temperature, irradiance level, and soil matric potential. Net photosynthesis of leaves under saturating irradiance (PPFD3= 1850 (μE·m–2·s−1) was optimum at about 20 C. At 25 C, net photosynthesis was nearly 90% of maximum at a PPFD of 800 μE·m–2·−1. Transpiration, and presumably water use, increased steadily with temperature from 10 to 40 C. Dark respiration rate and compensation points for light and for CO2increased exponentially, or nearly so, from 10 to 40 C. Soil moisture deficits of −130 kPa reduced net photosynthesis and transpiration by about 30 and 55%, respectively, compared to well-watered plants.

Information support for expert evaluation of the states of the external environment

2020 ◽  
pp. 71-76
Author(s):  
Rasol Murtadha Najah
Keyword(s):  
Decision Making ◽  
Environmental Conditions ◽  
Fuzzy Inference ◽  
Environmental Parameters ◽  
Information Support ◽  
Expert Assessment ◽  
Fuzzy Variables ◽  
Decision Making Models ◽  
The Difference ◽  
State Of The Environment

This article discusses the application of methods to enhance the knowledge of experts to build a decision-making model based on the processing of physical data on the real state of the environment. Environmental parameters determine its ecological state. To carry out research in the field of expert assessment of environmental conditions, the analysis of known works in this field is carried out. The results of the analysis made it possible to justify the relevance of the application of analytical, stochastic models and models based on methods of enhancing the knowledge of experts — experts. It is concluded that the results of using analytical and stochastic objects are inaccurate, due to the complexity and poor mathematical description of the objects. The relevance of developing information support for an expert assessment of environmental conditions is substantiated. The difference of this article is that based on the analysis of the application of expert methods for assessing the state of the environment, a fuzzy logic adoption model and information support for assessing the environmental state of the environment are proposed. The formalization of the parameters of decision-making models using linguistic and fuzzy variables is considered. The formalization of parameters of decision-making models using linguistic and fuzzy variables was considered. The model’s description of fuzzy inference is given. The use of information support for environment state assessment is shown on the example of experts assessing of the land desertification stage.

scholarly journals A Microtester for Measuring the Reliability of Microdevices in Controlled Environmental Conditions

Micromachines ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 585
Author(s):  
Yunjia Li ◽  
Weitao Dou ◽  
Chenyuan Zhou ◽  
Xinyi Wang ◽  
Aijun Yang ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Environmental Parameters ◽  
Test System ◽  
Standard Test ◽  
Electrical Parameters ◽  
Vibration Energy Harvester ◽  
Electromagnetic Vibration ◽  
Small Footprint ◽  
Humidity Range ◽  
Decoupling Algorithm

A miniaturized reliability test system for microdevices with controlled environmental parameters is presented. The system is capable of measuring key electrical parameters of the microdevices while controlling the environmental conditions around the microdevices. The test system is compact and thus can be integrated with standard test equipment for microdevices. By using a feed-forward decoupling algorithm, the presented test system is capable of generating a temperature range of 0–120 °C and a humidity range of 20–90% RH (0–55 °C), within a small footprint and weight. The accuracy for temperature and humidity control is ±0.1 °C and ±1% RH (30 °C), respectively. The functionality of the proposed test system is verified by integrating it with a piezo shaker to test the environmental reliability of an electromagnetic vibration energy harvester. The proposed system can be used as a proof-of-technology platform for characterizing the performance of microdevices with controlled environmental parameters.

Contrasting yield formation characteristics in two super-rice hybrids that differ in growth duration

2021 ◽  
pp. 1-10
Author(s):  
Min Huang ◽  
Zui Tao ◽  
Tao Lei ◽  
Fangbo Cao ◽  
Jiana Chen ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Biomass Production ◽  
Field Experiments ◽  
Crop Improvement ◽  
Total Biomass ◽  
Growth Duration ◽  
Area Index ◽  
Rice Hybrid ◽  
Use Efficiency ◽  
Yield Formation

Summary The development of high-yielding, short-duration super-rice hybrids is important for ensuring food security in China where multiple cropping is widely practiced and large-scale farming has gradually emerged. In this study, field experiments were conducted over 3 years to identify the yield formation characteristics in the shorter-duration (∼120 days) super-rice hybrid ‘Guiliangyou 2’ (G2) by comparing it with the longer-duration (∼130 days) super-rice hybrid ‘Y-liangyou 1’ (Y1). The results showed that G2 had a shorter pre-heading growth duration and consequently a shorter total growth duration compared to Y1. Compared to Y1, G2 had lower total biomass production that resulted from lower daily solar radiation, apparent radiation use efficiency (RUE), crop growth rate (CGR), and biomass production during the pre-heading period, but the grain yield was not significantly lower than that of Y1 because it was compensated for by the higher harvest index that resulted from slower leaf senescence (i.e., slower decline in leaf area index during the post-heading period) and higher RUE, CGR, and biomass production during the post-heading period. Our findings suggest that it is feasible to reduce the dependence of yield formation on growth duration to a certain extent in rice by increasing the use efficiency of solar radiation through crop improvement and also highlight the need for a greater fundamental understanding of the physiological processes involved in the higher use efficiency of solar radiation in super-rice hybrids.

Sign in / Sign up

Export Citation Format

Share Document