Radiation interception and biomass accumulation in a sugarcane crop grown under irrigated tropical conditions

1994 ◽  
Vol 45 (1) ◽  
pp. 37 ◽  
Author(s):  
RC Muchow ◽  
MF Spillman ◽  
AW Wood ◽  
MR Thomas
Keyword(s):  
Climatic Factors ◽  
Maximum Yield ◽  
Biomass Accumulation ◽  
Cane Yield ◽  
Future Research ◽  
Area Index ◽  
Radiation Interception ◽  
Sugarcane Crop ◽  
Tropical Conditions ◽  
The Relationship

Little quantitative information relating yield accumulation in sugarcane to climatic factors is available to allow the maximum yield in different seasons and locations to be determined. By comparison of actual yield with the climatically determined maximum yield for a given crop, the extent of yield limitation due to management and soil and pest factors can be assessed. This paper analyses the relationship between radiation interception and biomass accumulation for an autumn-planted sugarcane crop grown under irrigated conditions at Ayr, Qld (lat. 19.5� S.). Crop samplings were conducted from 167 to 445 days after planting (DAP). Less than 60% of the seasonal incident solar radiation was intercepted by the crop. A radiation extinction coefficient of 0.38 was estimated from the relationship between green leaf area index and the fraction of the radiation intercepted (fi). A maximum crop radiation (SW, 0.35-2-5 8m) use efficiency (RUE) of 1.75 g MJ-1 was determined. The maximum crop growth rate over a 140 day period was 41.1 g m-2d-1. However, this value is dependent on fi and the incident radiation ( S ) , and accordingly would be expected to vary across locations. In contrast, the RUE value of 1.75 g MJ-1is independent of fi and S, and can be used as a baseline value to assess the extent of yield limitation and the scope for yield improvement at different locations. The maximum biomass production was 72 t ha-1and the maximum fresh cane yield was 201 t ha-1. However, these maximum yields were attained up to 4 months before the final sampling. Future research should examine the wider applicability of this early yield plateau, and focus on the factors responsible for the early cessation in yield accumulation.

scholarly journals Potato Maximum Yield as Affected by Crop Parameters and Climatic Factors in Brazil

HortScience ◽  
2008 ◽  
Vol 43 (5) ◽  
pp. 1611-1614 ◽  
Author(s):  
André Pereira ◽  
Nilson Villa Nova
Keyword(s):  
Dry Matter ◽  
Climatic Factors ◽  
Maximum Yield ◽  
Crop Productivity ◽  
Matter Content ◽  
Dry Matter Content ◽  
Potato Tubers ◽  
Tropical Conditions ◽  
Potato Yields ◽  
Crop Parameters

There is currently a great deal of interest in estimating crop productivity as a function of climatic factors by means of different crop weather models. In this article, an agrometeorological model based on maximum carbon dioxide assimilation rates for C3 plants, fraction of photosynthetically active radiation, air temperature, photoperiod duration, and crop parameters is assessed as to its performance under tropical conditions. Crop parameters include leaf area, harvest index, dry matter content of potato tubers, and crop cycles to estimate potential potato yields. Productivity obtained with the cultivar Itararé, grown with adequate soil water supply conditions at four different sites in the state of São Paulo (Itararé, Piracicaba, Tatuí, and São Manuel), Brazil, was used to test the model. The results revealed excellent performance of the agrometeorological model proposed here with an underestimation of irrigated potato productivity of less than 10%.

scholarly journals A New Linear Relation for Estimating Surface Broadband Emissivity in Arid Regions Based on FTIR and MODIS Products

2021 ◽  
Vol 13 (9) ◽  
pp. 1686
Author(s):  
Huoqing Li ◽  
Zonghui Liu ◽  
Ali Mamtimin ◽  
Junjian Liu ◽  
Yongqiang Liu ◽  
...  
Keyword(s):  
Land Surface ◽  
Arid Regions ◽  
Mean Squared Error ◽  
Single Channel ◽  
Radiation Budget ◽  
Future Research ◽  
Inhomogeneous Surface ◽  
Imaging Spectrometer ◽  
Area Index ◽  
The Relationship

Broadband emissivity is a crucial parameter for calculating the radiation budget, still, it adopts a constant value in land surface models due to a lack of adequate observations. Arid regions have complex underlying surfaces and estimations of the broadband emissivity in such areas suffer from high spatial variation and uncertainty. Here, we propose a novel method for estimating broadband emissivity in the 8–14 µm range based on Fourier-transform infrared spectroscopy (FTIR) observations, moderate resolution imaging spectrometer (MODIS) emissivity, the leaf area index (LAI) and reflectance products. The proposed method exploits FTIR observations, MODIS single-channel emissivity, reflectance and the LAI to fit a linear regression of the broadband emissivity, so the optimal equation includes emissivity, reflectance and the LAI, with an R2 and root-mean-squared error of 0.942 and 0.08. Then we used the proposed method to generate a broadband emissivity map of Northwest of China, the broadband emissivity estimated by the method showed higher variations and finer distribution in arid areas and sparsely vegetated regions compared to data from the global land surface satellite and land model. An analysis of the relationship between the broadband emissivity, land-use type and soil moisture found an existing but not linear relationship, which indicated that the relationship was complicated under the inhomogeneous surface of wetness and vegetation. In conclusion, our results suggest that the proposed method can accurately estimate the broadband emissivity in arid regions. In future research, we will test the data in a land model.

scholarly journals Identification of climatic and physiological variables associated with rice (Oryza sativa L.) yield under tropical conditions

2019 ◽  
Vol 72 (1) ◽  
pp. 8699-8706 ◽  
Author(s):  
Yeison Mauricio Quevedo Amaya ◽  
Jose Isidro Beltrán Medina ◽  
Eduardo Barragán Quijano
Keyword(s):  
Solar Radiation ◽  
Climatic Factors ◽  
Oryza Sativa L ◽  
Block Design ◽  
Climatic Conditions ◽  
Phenological Stages ◽  
Area Index ◽  
Physiological Variables ◽  
Sowing Dates ◽  
Tropical Conditions

Rice crop productivity is influenced by climatic conditions such as solar radiation, temperature, and water availability during its vegetative and reproductive stage. In Colombia, rice cultivation is carried out throughout the year; so, it is necessary to identify the sowing dates where high yields are obtained, and which physiologic and climatic factors significantly influence them. Therefore, this research aimed to identify the key climatic and physiological factors that allow maximizing the yield and maintaining good productivity in sowing dates with optimal and deficient environmental conditions, respectively. The experiment was carried out in a rice producing region in northern of Tolima, Colombia from 2015 to 2016. Ten sowing dates were established, with a randomized complete block design in a divided strips arrangement. For each sowing date, climatic conditions were tracked, and growth, development, and yield of rice plant were evaluated. Also, the photosynthetic rate was assessed on five sowing dates. Results showed that physiologic factors that have more relation with crop yield are plant height, leaf area index and dry mass accumulation between phenological stages 37 and 49; whereas the unique climatic factor, that was highly related to yield, was solar radiation between phenological stages 51 to 77. Furthermore, when the optimum values of each variable were reached, a yield higher than 9,500 kg ha-1 was achieved. No relation was observed between the photosynthesis rate of at leaf level and yield.

scholarly journals DISCRIMINATION OF SUGARCANE CROP AND CANE YIELD ESTIMATION USING LANDSAT AND IRS RESOURCESAT SATELLITE DATA

2019 ◽  
Vol XLII-3/W6 ◽  
pp. 229-233 ◽  
Author(s):  
S. Pandey ◽  
N. R. Patel ◽  
A. Danodia ◽  
R. Singh
Keyword(s):  
Satellite Data ◽  
Research Work ◽  
Cane Yield ◽  
Landsat 8 ◽  
Yield Estimation ◽  
Area Index ◽  
Acreage Estimation ◽  
Sugarcane Crop ◽  
Field Level ◽  
Crop Discrimination

<p><strong>Abstract.</strong> The objective of this research work aims at crop acreage estimation at mill catchment level, derivation of sugarcane phenology and yield estimation at field level. The study was carried out in Kisan Sahkari Chini Mill catchment, Nanauta, Saharanpur, Uttar Pradesh. Extensive and systematic field sampling was carried out for ground-truth observations, biophysical measurements (LAI and above/below canopy PAR) and mill-able cane yield through crop cutting experiments. Major emphasis were laid on sugarcane crop discrimination, biophysical parameter estimation, generation of phenological metrics and yield model development for sugarcane crop at mill catchment level. Sugarcane crop discrimination and its acreage estimation was done using multi-sensor satellite data. The sugarcane classification accuracies were &amp;gt;&amp;thinsp;92% for LISS-IV, &amp;gt;&amp;thinsp;86% for Landsat-8 and &amp;gt;&amp;thinsp;83% for LISS-III classified image. The sugarcane phenological matrices at field level derived using time-series of NDVI for a period of 2015&amp;ndash;2016 through TIMESAT software. To retrieve the biophysical parameters particularly leaf area index, best predictive function developed with vegetation indices (EVI, NDVI, SAVI) through correlation and regression analysis along this cane yield estimation attempted with multi-date (eight-day) NDVI from Landsat OLI. Yield models developed for ratoon cane and planted cane explained variance in yield significantly with coefficient of determination (R<sup>2</sup>) values equal to 0.83 and 0.69, respectively. Similar predictive functions were also established with monthly composite dataset for village-level yield estimates with step wise regression (R<sup>2</sup>&amp;thinsp;=&amp;thinsp;0.83) (P&amp;thinsp;=&amp;thinsp;0.00001), Multi linear regression (MLR) (R<sup>2</sup>&amp;thinsp;=&amp;thinsp;0.792) (P&amp;thinsp;=&amp;thinsp;0.00081) and Random forest regression (R<sup>2</sup>&amp;thinsp;=&amp;thinsp;0.466) (P&amp;thinsp;=&amp;thinsp;0.038).</p>

Symptoms of Alcohol Dependence Predict Suicide Ideation Among Alaskan Undergraduates

Crisis ◽  
2016 ◽  
Vol 37 (3) ◽  
pp. 232-235 ◽  
Author(s):  
Christopher R. DeCou ◽  
Monica C. Skewes
Keyword(s):  
Depressive Symptoms ◽  
Alcohol Consumption ◽  
Alcohol Dependence ◽  
Suicide Ideation ◽  
Alcohol Problems ◽  
Future Research ◽  
Causal Mechanism ◽  
Students At Risk ◽  
The Relationship ◽  
Alcohol Related Problems

Abstract. Background: Previous research has demonstrated an association between alcohol-related problems and suicidal ideation (SI). Aims: The present study evaluated, simultaneously, alcohol consequences and symptoms of alcohol dependence as predictors of SI after adjusting for depressive symptoms and alcohol consumption. Method: A sample of 298 Alaskan undergraduates completed survey measures, including the Young Adult Alcohol Consequences Questionnaire, the Short Alcohol Dependence Data Questionnaire, and the Beck Depression Inventory – II. The association between alcohol problems and SI status was evaluated using sequential logistic regression. Results: Symptoms of alcohol dependence (OR = 1.88, p < .05), but not alcohol-related consequences (OR = 1.01, p = .95), emerged as an independent predictor of SI status above and beyond depressive symptoms (OR = 2.39, p < .001) and alcohol consumption (OR = 1.08, p = .39). Conclusion: Alcohol dependence symptoms represented a unique risk for SI relative to alcohol-related consequences and alcohol consumption. Future research should examine the causal mechanism behind the relationship between alcohol dependence and suicidality among university students. Assessing the presence of dependence symptoms may improve the accuracy of identifying students at risk of SI.

The Relationship Between Interoception and Metacognition

2016 ◽  
Vol 30 (2) ◽  
pp. 76-86 ◽  
Author(s):  
Judith Meessen ◽  
Verena Mainz ◽  
Siegfried Gauggel ◽  
Eftychia Volz-Sidiropoulou ◽  
Stefan Sütterlin ◽  
...  
Keyword(s):  
Memory Performance ◽  
Memory Task ◽  
Demographic Characteristics ◽  
Metacognitive Awareness ◽  
Interoceptive Awareness ◽  
Future Research ◽  
Heartbeat Perception ◽  
Interoceptive Accuracy ◽  
The Relationship

Abstract. Recently, Garfinkel and Critchley (2013) proposed to distinguish between three facets of interoception: interoceptive sensibility, interoceptive accuracy, and interoceptive awareness. This pilot study investigated how these facets interrelate to each other and whether interoceptive awareness is related to the metacognitive awareness of memory performance. A sample of 24 healthy students completed a heartbeat perception task (HPT) and a memory task. Judgments of confidence were requested for each task. Participants filled in questionnaires assessing interoceptive sensibility, depression, anxiety, and socio-demographic characteristics. The three facets of interoception were found to be uncorrelated and interoceptive awareness was not related to metacognitive awareness of memory performance. Whereas memory performance was significantly related to metamemory awareness, interoceptive accuracy (HPT) and interoceptive awareness were not correlated. Results suggest that future research on interoception should assess all facets of interoception in order to capture the multifaceted quality of the construct.

The Relationship Between Leader–Member Exchange and Employees’ Proactive Behaviors

2019 ◽  
Vol 18 (2) ◽  
pp. 106-111
Author(s):  
Fong-Yi Lai ◽  
Szu-Chi Lu ◽  
Cheng-Chen Lin ◽  
Yu-Chin Lee
Keyword(s):  
Hierarchical Linear Modeling ◽  
Future Research ◽  
Leader Member Exchange ◽  
Voice Behavior ◽  
Linear Modeling ◽  
Team Members ◽  
Member Exchange ◽  
Multi Temporal ◽  
The Relationship ◽  
Practical Implications

Abstract. The present study proposed that, unlike prior leader–member exchange (LMX) research which often implicitly assumed that each leader develops equal-quality relationships with their supervisors (leader’s LMX; LLX), every leader develops different relationships with their supervisors and, in turn, receive different amounts of resources. Moreover, these differentiated relationships with superiors will influence how leader–member relationship quality affects team members’ voice and creativity. We adopted a multi-temporal (three wave) and multi-source (leaders and employees) research design. Hypotheses were tested on a sample of 227 bank employees working in 52 departments. Results of the hierarchical linear modeling (HLM) analysis showed that LLX moderates the relationship between LMX and team members’ voice behavior and creative performance. Strengths, limitations, practical implications, and directions for future research are discussed.

Coping Humor as a Mediator Between Emotional Intelligence and Job Satisfaction

2017 ◽  
Vol 16 (3) ◽  
pp. 155-159 ◽  
Author(s):  
Peizhen Sun ◽  
Jennifer J. Chen ◽  
Hongyan Jiang
Keyword(s):  
Job Satisfaction ◽  
Emotional Intelligence ◽  
Future Research ◽  
Satisfaction Scale ◽  
Primary School Teachers ◽  
Mediating Role ◽  
Regulation Of Emotion ◽  
The Relationship ◽  
Overall Job Satisfaction

Abstract. This study investigated the mediating role of coping humor in the relationship between emotional intelligence (EI) and job satisfaction. Participants were 398 primary school teachers in China, who completed the Wong Law Emotional Intelligence Scale, Coping Humor Scale, and Overall Job Satisfaction Scale. Results showed that coping humor was a significant mediator between EI and job satisfaction. A further examination revealed, however, that coping humor only mediated two sub-dimensions of EI (use of emotion and regulation of emotion) and job satisfaction. Implications for future research and limitations of the study are discussed.

Workplace Ostracism and Its Negative Outcomes

2016 ◽  
Vol 15 (4) ◽  
pp. 143-151 ◽  
Author(s):  
Xiaoming Zheng ◽  
Jun Yang ◽  
Hang-Yue Ngo ◽  
Xiao-Yu Liu ◽  
Wengjuan Jiao
Keyword(s):  
Affective Commitment ◽  
Psychological Capital ◽  
Intention To Leave ◽  
Future Research ◽  
Conservation Of Resources ◽  
Negative Consequences ◽  
Negative Outcomes ◽  
Workplace Ostracism ◽  
Using Data ◽  
The Relationship

Abstract. Workplace ostracism, conceived as to being ignored or excluded by others, has attracted the attention of researchers in recent years. One essential topic in this area is how to reduce or even eliminate the negative consequences of workplace ostracism. Based on conservation of resources (COR) theory, the current study assesses the relationship between workplace ostracism and its negative outcomes, as well as the moderating role played by psychological capital, using data collected from 256 employees in three companies in the northern part of China. The study yields two important findings: (1) workplace ostracism is positively related to intention to leave and (2) psychological capital moderates the effect of workplace ostracism on affective commitment and intention to leave. This paper concludes by discussing the implications of these findings for organizations and employees, along with recommendations for future research.

Moderating Role of Gender in the Relationship between Cognitive Errors and Anxiety among Adolescents

2020 ◽  
Vol 4 (1) ◽  
pp. 86-102
Author(s):  
Tasnim Rehna ◽  
Rubina Hanif ◽  
Muhammad Aqeel
Keyword(s):  
Mental Health Problems ◽  
Adolescent Psychopathology ◽  
Future Research ◽  
Cognitive Errors ◽  
Adolescent Anxiety ◽  
Study Results ◽  
The Status ◽  
Manifest Anxiety ◽  
The Relationship

Background: Widespread social paradigms on which the status variances are grounded in any society, gender plays pivotal role in manifestation of mental health problems (Rutter, 2007). A hefty volume of research has addressed the issue in adults nonetheless, little is vividly known about the role of gender in adolescent psychopathology. Sample: A sample of 240 adolescents (125 boys, 115 girls) aging 12-18 years was amassed from various secondary schools of Islamabad with the approval of the Federal Directorate of Education (FDE), relevant authorities of the schools and the adolescents themselves. Instruments: Taylor Manifest Anxiety Scale (Taylor & Spence, 1953) and Children’s Negative Cognitive Errors Questionnaire (CNCEQ) by Leitenberg et al., (1986) were applied in present study. Results: Multiple regression analysis revealed that cognitive errors jointly accounted for 78% of variance in predicting anxiety among adolescents. Findings also exhibited that gender significantly moderated the relationship between cognitive errors and adolescent anxiety. Implications of the findings are discoursed for future research and clinical practice.

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