scholarly journals Analysis of Drought Characteristics and Its Effects on Crop Yield in Xinjiang in Recent 60 Years

2021 ◽  
Vol 13 (24) ◽  
pp. 13833
Author(s):  
Junqi Cheng ◽  
Shuyan Yin
Keyword(s):  
Global Warming ◽  
Regression Analysis ◽  
Seasonal Variation ◽  
Crop Yield ◽  
Annual Variation ◽  
Unit Area ◽  
Drought Characteristics ◽  
Increasing Trend ◽  
Different Seasons ◽  
Ecological Construction

With global warming, the frequency of drought in China is gradually increasing. The study of drought characteristics and its impact on crop yield is of great significance to ecological construction and food security. Based on the SPEI index in Xinjiang from 1961 to 2020, the changing characteristics of drought and their responses to meteorological yield of three kinds of crops (cotton, wheat and corn) were analyzed. The results revealed that the SPEI in Xinjiang exhibited a decreasing trend. Drought occurred less during 1961–1996 and mainly occurred during 1997–2020. The annual variation trend of SPEI decreased regionally, and the arid trend increased from northwest to southeast. The seasonal variation in SPEI displayed an increasing trend only in winter, but a decreasing trend in spring, summer and autumn. The decreasing trend of the SPEI index in spring accounted for 90.91%, mainly distributed in the central and eastern part of Xinjiang; the decreasing trend in summer accounted for 81.82%, mainly located in the eastern part of Xinjiang; the decreasing trend in autumn accounted for 84.85%, mainly located in the south and central and eastern part of Xinjiang; the decreasing trend in winter accounted for only 33.33%, mainly located in the southwest, central and eastern part of Xinjiang; the per unit area yield of the three kinds of crops showed a significant increasing trend (p < 0.01). The meteorological yield of cotton showed an increasing trend, while that of wheat and corn showed a decreasing trend. Correlation analysis of climatic yield and SPEI, and regression analysis of standardized climatic yield residuals and SPEI in different seasons revealed that drought in spring and autumn had the greatest effect on the meteorological yield of cotton, while drought in spring and summer had the greatest effect on the meteorological yield of wheat and corn.

scholarly journals Seasonal Variation of Kaurenoic Acid, a Hypoglycemic Diterpene Present in Wedelia paludosa (Acmela brasiliensis) (Asteraceae)

2004 ◽  
Vol 59 (3-4) ◽  
pp. 229-232 ◽  
Author(s):  
Louisiane Faccio V. Bresciania ◽  
Rosendo Augusto Yunes ◽  
Cristiani Bürger ◽  
Luis Eduardo De Oliveira ◽  
Kauê Leal Bóf ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Kaurenoic Acid ◽  
Different Seasons ◽  
Hypoglycemic Diterpene

We evaluated the variation of the concentration of kaurenoic acid (1), which is a bioactive diterpene, in leaves, flowers, stems and roots from Wedelia paludosa (Acmela brasiliensis) for different seasons using the HRGC/FID method. The results indicated that the concentration of 1 is higher in the roots and stems during the autumn. The pharmacological results suggested that kaurenoic acid is responsible, at least in part, for the hypoglycemic potential detected in this plant.

Evaluation of Imazethapyr for Weed Control in Leafy Vegetable Crops

1996 ◽  
Vol 10 (2) ◽  
pp. 253-257 ◽  
Author(s):  
Joan A. Dusky ◽  
William M. Stall
Keyword(s):  
Regression Analysis ◽  
Weed Control ◽  
Crop Yield ◽  
Relative Sensitivity ◽  
Leafy Vegetable ◽  
Field Conditions ◽  
Vegetable Crops ◽  
Weed Species ◽  
Common Lambsquarters ◽  
Common Purslane

Imazethapyr was evaluated PRE and POST in five lettuce types and chicory under Florida field conditions. The relative sensitivity of leafy crop vigor (most sensitive to most tolerant) to imazethapyr PRE, based on 20% inhibition determined using regression analysis, was as follows: Boston > bibb > crisphead > romaine > leaf > escarole > endive. Leafy crop injury increased as the rate of imazethapyr applied POST increased, with all leafy crops responding in a similar manner. Surfactant addition increased imazethapyr phytotoxicity. Imazethapyr PRE treatments at 0.067 kg ai/ha provided greater than 80% control of livid amaranth, common purslane, flatsedge, and common lambsquarters. Imazethapyr POST at 0.067 kg/ha, with surfactant provided control greater than 85% of all weed species. Greater than 85% spiny amaranth control was provided by imazethapyr POST at 0.017 kg/ha. Use of surfactant with imazethapyr did not improve spiny amaranth control over imazethapyr with no surfactant. POST treatments did not decrease leafy crop yield compared with the hand-weeded check. Imazethapyr applied PRE reduced crop yield compared to the POST treatments and the hand-weeded control.

Changes in tobacco depictions after implementation of tobacco-free film and TV rules in Bollywood films in India: a trend analysis

2021 ◽  
pp. tobaccocontrol-2021-056629
Author(s):  
Gaurang P Nazar ◽  
Monika Arora ◽  
Nitika Sharma ◽  
Surbhi Shrivastava ◽  
Tina Rawal ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Trend Analysis ◽  
Poisson Regression ◽  
Poisson Regression Analysis ◽  
Free Film ◽  
Rule Compliance ◽  
Increasing Trend ◽  
Before And After ◽  
Year 2013

BackgroundIndia’s tobacco-free film and TV rules were implemented from 2012. To assess the effect of the rules, we studied tobacco depictions in top-grossing Bollywood films released between 2006 and 2017 and rule compliance after 2012.MethodsTobacco incidents and brand appearances were coded in 240 top-grossing Bollywood films (2006–2017) using the Breathe California method. Trends in number of tobacco incidents per film per year were studied before and after implementation of the rules using Poisson regression analysis. Compliance with rules over the years was studied using Pearson product-moment correlations.ResultsForty-five films were U-rated (all ages), 162 were UA-rated (below age 12 years must be adult-accompanied), and 33 were A-rated (age 18+ years only). Before implementation of the rules, the number of tobacco incidents per film was increasing by a factor of 1.1/year (95% CI 1.0 to 1.2, p=0.002). However, beginning year 2013, the number of incidents per film started falling significantly by a factor of 0.7/year (95% CI 0.6 to 0.9; p=0.012) compared with the previous increasing trend. The percentage of youth-rated (U and UA) films with any tobacco incidents also declined from a peak of 76% in 2012 to 35% in 2017. The percentage of films complying with the rules (audio-visual disclaimers, health spots, static warnings) did not change significantly from 2012 to 2017.ConclusionIndia’s 2012 rules were followed by a reduction in tobacco depictions in Bollywood films. Enhanced monitoring of compliance is needed to ensure the continued effectiveness of the rules.

scholarly journals More Irrigated Crop Production with Less Water Use

2019 ◽  
pp. 218-226
Author(s):  
Ahmed Ibrahim Ekhmaj ◽  
Younes Daw Ezlit ◽  
Mukhtar Mahmud Elaalem
Keyword(s):  
Crop Yield ◽  
Irrigation Water ◽  
Performance Indicators ◽  
Unit Volume ◽  
Unit Area ◽  
Irrigation Management ◽  
Agricultural Practices ◽  
Common Practices ◽  
The Common ◽  
Production Output

Three major performance indicators developed by the International Water Management Institute (IWMI, 1998) are used in this paper to evaluate the performance of the irrigated crops in the region according to the commonly followed practices among farmers as compared with their performance under conditions of much improved irrigation management and agricultural practices. These indicators include the Standardized Gross Value Production (SGVP), the unit area production output (crop yield or its financial value per hectare) and the unit volume of irrigation water production output (crop yield or its financial value per cubic meter). The comparison between the two agricultural practices indicated that the unit area output of the common practices among farmers did not exceed 6483 Libyan Dinars / hectare, while that under the improved practices was 11605 Libyan Dinars / hectare. The unit volume of irrigation water output for the common practices was 0.63 Libyan Dinar / cubic meter, while that under the improved practices reached 1.63 Libyan Dinar / cubic meter. These results clearly show the importance of the applied performance indicators in the assessment and clarification of the economic impacts of any introduced interventions aiming at the improvement of and/or the differentiation among irrigation management practices and alternative agricultural cropping systems.

Vitamin D (25-OH) concentrations in hospitalized patients, outpatients and dialysis patients depending on seasonal variation

2015 ◽  
Vol 51 (3) ◽  
pp. 209-212
Author(s):  
Magdalena Maria Ostrowska ◽  
Ewa Szulc-Mysińska ◽  
Dagna Bobilewicz ◽  
Marta Faryna
Keyword(s):  
Vitamin D ◽  
Seasonal Variation ◽  
Seasonal Changes ◽  
Hospitalized Patients ◽  
Optimum Concentration ◽  
Dialysis Patients ◽  
Total Vitamin ◽  
Different Seasons ◽  
Mean Concentration ◽  
Global Health Problem

Vitamin D deficiency, which is a global health problem, may result in numerous diseases, such as rickets in children and osteoporosis and osteomalacia in adults. The occurrence of the above-mentioned disorders is promoted by the wintertime and higher latitudes. The aim of the study was to compare the concentrations of vitamin D (25-OH) in hospitalized patients and outpatients in different seasons of the year (summer and winter), as well as in dialysis patients in December and May. The Roche test for the quantitativedetermination of total vitamin D (25-OH) was used in the study. The range from 30 to 80 ng/ml was accepted as the optimum concentration. In hospitalized patients and outpatients, both in summer and winter mean concentration of vitamin D (25-OH) reached the values below 30 ng/ml in over 80% of the patients. Only in the hospitalized patient group mean concentration of vitamin D (25-OH) in the summer was significantly higher than in the winter (p=0.0016). In the dialysis patients mean concentration of vitamin (25-OH) in May was significantly higher than in December (p=0.0085) and the percent of the results below 30 ng/ml amounted to 96.39% in December and 77.27% in May. In conclusion, the 25(OH)D concentrations in the whole population under study are lower than those recommended and undergo periodical seasonal changes in hospitalized patients.

Simple linear regression.

2021 ◽  
pp. 80-145
Author(s):  
Edward F. Durner
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Crop Yield ◽  
Repeated Measures ◽  
Polynomial Regression ◽  
Linear Regression Analysis ◽  
Confidence Bands ◽  
Simple Linear Regression ◽  
Nitrogen Rate ◽  
Mathematical Equations

Abstract This chapter covers the methods for obtaining and expressing these mathematical equations and their confidence bands. The methodology is linear regression analysis. Four types of regression analysis are presented, including: simple linear regression with no repeated measures or replication; simple linear regression with repeated measures; simple linear regression with replication; and polynomial regression. The effects of nitrogen rate on crop yield were presented as example.

scholarly journals Algal flora of Rajarani Lake, Dhankuta and their seasonal distribution

Our Nature ◽  
2017 ◽  
Vol 15 (1-2) ◽  
pp. 44-54
Author(s):  
Govinda Shrestha ◽  
Shiva Kumar Rai
Keyword(s):  
Seasonal Variation ◽  
Rainy Season ◽  
Physicochemical Parameters ◽  
Winter Season ◽  
Single Species ◽  
Seasonal Distribution ◽  
Algal Flora ◽  
Ankistrodesmus Falcatus ◽  
Different Seasons ◽  
Aulacoseira Granulata

In this paper, a total 46 algae belonging to 34 genera and 3 classes (Chlorophyceae 54%, Bacillariophyceae 28%, Cyanophyceae 18%) have been reported from Rajarani Lake, Dhankuta, Nepal. Among these, 13 algae were reported as new to the country. Genera Ankistrodesmus, Closterium, and Desmodesmus had maximum number of species whereas 25 genera were represented by single species. Seasonal variation of algae showed that there was changing number and type of algae with physicochemical parameters in different seasons. Cyanophycean algae Microcystis flos-aque was dominant and observed in all sites in every collection of winter, summer and rainy seasons, and followed by bacillariophyceaean algae i.e., Aulacoseira granulata var. angustissima. The maximum number of algae was found in summer (59%) followed by winter (50%) and rainy (31%) seasons. There were 6 common algae found in all season’s viz. Ankistrodesmus falcatus, Aulacoseira granulata var. angustissima, Flagilaria tenera, Microcystis flos-aquae, Navicula radiosa and Oedogonium sp. Algae viz., Anabaena affinis, Cyclotella meneghiana, Pinnularia divergens, Pinnularia interrupta, Tetrastrum heteracanthum, and Ulothrix subtilissima were found only in winter season whereas, Aulacoseirsa granulata var. muzzanensis, Bolbochaete sp, Closterium striolatum, Cylindrospermum muscicola, Desmodesmus abundans, Desmodesmous quadricauda var.bicaudatus, Eunotia bilunaris, Gomphonema lacusrankaloides and Gomphonema pseudoaugur were observed only in summer. Similarly, Aphanocapsa pulchra, Oscillatoria sancta and Pediastrum duplex var. gracillimum were reported only in rainy season.

scholarly journals Seroprevalence and Risk Factors ofChlamydia abortusInfection in Tibetan Sheep in Gansu Province, Northwest China

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Si-Yuan Qin ◽  
Ming-Yang Yin ◽  
Wei Cong ◽  
Dong-Hui Zhou ◽  
Xiao-Xuan Zhang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Logistic Regression ◽  
Regression Analysis ◽  
Logistic Regression Analysis ◽  
Multivariate Logistic Regression Analysis ◽  
Northwest China ◽  
Gansu Province ◽  
Factors Associated ◽  
Tibetan Sheep ◽  
Different Seasons

Chlamydia abortus, an important pathogen in a variety of animals, is associated with abortion in sheep. In the present study, 1732 blood samples, collected from Tibetan sheep between June 2013 and April 2014, were examined by the indirect hemagglutination (IHA) test, aiming to evaluate the seroprevalence and risk factors ofC. abortusinfection in Tibetan sheep. 323 of 1732 (18.65%) samples were seropositive forC. abortusantibodies at the cut-off of 1 : 16. A multivariate logistic regression analysis was used to evaluate the risk factors associated with seroprevalence, which could provide foundation to prevent and controlC. abortusinfection in Tibetan sheep. Gender of Tibetan sheep was left out of the final model because it is not significant in the logistic regression analysis (P>0.05). Region, season, and age were considered as major risk factors associated withC. abortusinfection in Tibetan sheep. Our study revealed a widespread and high prevalence ofC. abortusinfection in Tibetan sheep in Gansu province, northwest China, with higher exposure risk in different seasons and ages and distinct geographical distribution.

scholarly journals Variation of Seed Dosage on Corn Crop Production Components

2018 ◽  
Vol 10 (8) ◽  
pp. 296
Author(s):  
Rafael De Graaf Corrêa ◽  
Carlos Eduardo Angeli Furlani ◽  
Cristiano Zerbato ◽  
Danilo Tedesco de Oliveira ◽  
Mailson Freire de Oliveira
Keyword(s):  
Regression Analysis ◽  
Population Density ◽  
Crop Yield ◽  
Crop Production ◽  
Corn Yield ◽  
Corn Seed ◽  
Corn Crop ◽  
Positive Variation ◽  
Productive Potential ◽  
Corn Productivity

The variation in population density in a corn crop can positively, negatively or neutrally affects plant productivity depending on the productive potential of the area. The aim of this work was to evaluate the effects of the variation in corn seed dosage on crop yield, and define from which percentage of variation the productivity of the sown line is affected negatively. The experiment was installed at FCAV-UNESP, in Jaboticabal (SP), Brazil. Twelve variations on plant population were evaluated, ranging from -27% to 27%, varying with a frequency of 4.5%. The morphological and productive characteristics of each treatment were evaluated through regression analysis. Each 1% of negative variation on seed dosage was lost 1.06% in corn yield. Positive variations, however, presented changes that were 0 to -2.59%. Negative variations on seed dosage reduced corn productivity by up to 28%. The positive variation affects the productivity of the crop in a less accentuated way, with a reduction in productivity that reaches 2.59% in the largest variations and may even cause positive productivity results depending on the maximum potential of the area.

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