scholarly journals Type of Trellis Affects Radiation Absorption and Must Composition but not Yield of `Petite Sirah' Grapes

HortScience ◽  
1992 ◽  
Vol 27 (1) ◽  
pp. 20-22 ◽  
Author(s):  
T.H. Morsil ◽  
A.D. Matthias ◽  
J.L. Stroehlein
Keyword(s):  
Vitis Vinifera ◽  
Photosynthetically Active Radiation ◽  
Total Dissolved Solids ◽  
Radiation Absorption ◽  
Alcohol Content ◽  
Dissolved Solids ◽  
Active Radiation ◽  
Fruit Composition ◽  
Arid Conditions ◽  
Semi Arid

The effects of trellising on absorption of photosynthetically active radiation (PAR, 400- to 700-nm wavelength) by foliage and fruits, on fruit composition, and yield were studied in 1988 under semi-arid conditions using field-grown Vitis vinifera L. `Petite Sirah' grapevines in a mature vineyard. A vertical inclination was obtained by attaching shoots to a vertically arranged three-wire trellis; 60° shoot inclination from horizontal was obtained by attaching shoots to a “V-type” Tatura trellis; a standard two-wire trellis (control) was used in which shoots attached to the upper wire were permitted to orient downward to the vineyard floor. PAR absorption by foliage during mid-morning to mid-afternoon periods was highest in the standard trellis and lowest in the Tatura trellis. PAR available for absorption by fruits was lowest in the standard trellis and highest in the Tatura trellis. Analysis of fruit composition at harvest revealed that total dissolved solids (°Brix) was significantly higher for berries from the Tatura trellis than for the vertical trellis or the control. The Tatura trellis resulted in the highest alcohol content of wine. Per-vine yields did not differ significantly among the three trellis systems.

scholarly journals Drivers of inter-annual variability in Net Ecosystem Exchange in a semi-arid savanna ecosystem, South Africa

2009 ◽  
Vol 6 (2) ◽  
pp. 251-266 ◽  
Author(s):  
S. A. Archibald ◽  
A. Kirton ◽  
M. R. van der Merwe ◽  
R. J. Scholes ◽  
C. A. Williams ◽  
...  
Keyword(s):  
South Africa ◽  
Eddy Covariance ◽  
Photosynthetically Active Radiation ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Ann Model ◽  
Rainfall Events ◽  
Active Radiation ◽  
Annual Variability ◽  
Semi Arid

Abstract. Inter-annual variability in primary production and ecosystem respiration was explored using eddy-covariance data at a semi-arid savanna site in the Kruger Park, South Africa. New methods of extrapolating night-time respiration to the entire day and filling gaps in eddy-covariance data in semi-arid systems were developed. Net ecosystem exchange (NEE) in these systems occurs as pulses associated with rainfall events, a pattern not well-represented in current standard gap-filling procedures developed primarily for temperate flux sites. They furthermore do not take into account the decrease in respiration at high soil temperatures. An artificial neural network (ANN) model incorporating these features predicted measured fluxes accurately (MAE 0.42 gC/m2/day), and was able to represent the seasonal patterns of photosynthesis and respiration at the site. The amount of green leaf area (indexed using satellite-derived estimates of fractional interception of photosynthetically active radiation fAPAR), and the timing and magnitude of rainfall events, were the two most important predictors used in the ANN model. These drivers were also identified by multiple linear regressions (MLR), with strong interactive effects. The annual integral of the filled NEE data was found to range from −138 to +155 g C/m2/y over the 5 year eddy covariance measurement period. When applied to a 25 year time series of meteorological data, the ANN model predicts an annual mean NEE of 75(±105) g C/m2/y. The main correlates of this inter-annual variability were found to be variation in the amount of absorbed photosynthetically active radiation (APAR), length of the growing season, and number of days in the year when moisture was available in the soil.

scholarly journals A model of environmental limitations on production of Agave americana L. grown as a biofuel crop in semi-arid regions

2018 ◽  
Vol 70 (22) ◽  
pp. 6549-6559 ◽  
Author(s):  
Nicholas A Niechayev ◽  
Alexander M Jones ◽  
David M Rosenthal ◽  
Sarah C Davis
Keyword(s):  
Photosynthetically Active Radiation ◽  
Arid Regions ◽  
Physiological Responses ◽  
Field Conditions ◽  
Radiation Temperature ◽  
Biofuel Crop ◽  
Active Radiation ◽  
Agave Americana ◽  
Semi Arid

Physiological responses to variation in photosynthetically active radiation, temperature, and water can be used to predict the growth of Agave americana L. in field conditions.

The Effects of Streamflow Variability on Salt Flux in a Semi-Arid Tropical River Basin in Eastern Kenya

2019 ◽  
pp. 48-84
Author(s):  
Johnson Utu Kitheka
Keyword(s):  
River Basin ◽  
Significant Relationship ◽  
River Discharge ◽  
Total Dissolved Solids ◽  
Salt Flux ◽  
Tropical River ◽  
Dissolved Solids ◽  
Streamflow Variability ◽  
The Mean ◽  
Semi Arid

This chapter presents the results of a study on the influence of streamflow variability on salt fluxes in a semi-arid Tiva River Basin located in Eastern Kenya. Measurements of salinity, total dissolved solids (TDS), conductivity, and river discharges were undertaken in sampling stations located within the main branch of the river as well as in the tributaries, namely Kauwi, Kalundu, Nzeeu, and Mwitasyano Rivers in the Upper Region of the Tiva River Basin. The mean and maximum river discharges for the sub-basins of the river ranged from 11 to 33 m3s-1 and from 118 to 210 m3s-1, respectively. The peak river discharge at the main Tiva branch was 270 m3s-1. The study shows that there is a significant relationship between the variability of streamflow and the variability of salt fluxes in the river as exemplified by variation of salinity, conductivity, and TDS in the river.

scholarly journals Pengaruh Penambahan Ragi Tape dan Waktu Fermentasi Hasil Samping Cairan Pulpa terhadap Karakteristik Mutu Cuka Kakao (Theobroma cacao L.)

2020 ◽  
Vol 8 (2) ◽  
pp. 177
Author(s):  
Ida Bagus Gede Awidyanata ◽  
G.P Ganda Putra ◽  
Luh Putu Wrasiati
Keyword(s):  
Acetic Acid ◽  
Block Design ◽  
Total Dissolved Solids ◽  
Total Sugar ◽  
Alcohol Content ◽  
Dissolved Solids ◽  
Fermentation Time ◽  
Natural Fermentation ◽  
Acid Ph ◽  
Cocoa Bean Fermentation

The aim of this study was to determine the effect of adding ragi tape and the time of natural fermentation of the pulp byproducts of the fermented cocoa beans on the characteristics of the quality of cocoa vinegar and determining the addition of tape yeast and the natural fermentation time of the best pulp fluid for cocoa vinegar production. The experiments in this study used a randomized block design with two factors. The first factor is the addition of yeast tape consisting of 5 levels, namely without the addition of yeast tape (control), the addition of yeast tape 0.05% (w / v), 0.10% (w / v), 0.15% (w / v), 0.20% (w / v), the second factor is the fermentation time consisting of 6 levels, namely 5, 10, 15, 20, 25, 30 days. Treatment The addition of tape yeast has a very significant effect on acetic acid, pH, total dissolved solids, total sugar, has no significant effect on alcohol content in the fermented vinegar from the pulp fluid which is the by-product of cocoa bean fermentation. The length of fermentation treatment has a very significant effect on acetic acid, pH, total dissolved solids, total sugar, alcohol. The interaction between the two treatments had no significant effect on acetic acid, pH, total dissolved solids, alcohol content, and significant effect on total sugar in fermented cocoa vinegar products. The best treatment was obtained from the addition of 0.15% (w / v) yeast tape and 30 days fermentation time which produced cacao vinegar with acetic acid content of 2.40%, pH 3.37, total dissolved solids 4.25 obrix, total sugar 0.03%, and 0.00% alcohol. Keywords  : vinegar fermentasion, ragi tape, time of fermentation

scholarly journals Drivers of interannual variability in Net Ecosystem Exchange in a semi-arid savanna ecosystem, South Africa

2008 ◽  
Vol 5 (4) ◽  
pp. 3221-3266 ◽  
Author(s):  
S. Archibald ◽  
A. Kirton ◽  
M. van der Merwe ◽  
R. J. Scholes ◽  
C. A. Williams ◽  
...  
Keyword(s):  
South Africa ◽  
Eddy Covariance ◽  
Photosynthetically Active Radiation ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Ann Model ◽  
Rainfall Events ◽  
Active Radiation ◽  
Annual Variability ◽  
Semi Arid

Abstract. Inter-annual variability in primary production and ecosystem respiration was explored using eddy-covariance data at a semi-arid savanna site in the Kruger Park, South Africa. New methods of extrapolating night-time respiration to the entire day and filling gaps in eddy-covariance data in semi-arid systems were developed. Net ecosystem exchange (NEE) in these systems occurs as pulses associated with rainfall events, a pattern not well-represented in current standard gap-filling procedures developed primarily for temperate flux sites. They furthermore do not take into account the decrease in respiration at high soil temperatures. An artificial neural network (ANN) model incorporating these features predicted measured fluxes accurately (MAE 0.42 g C/m2/day), and was able to represent the seasonal patterns of photosynthesis and respiration at the site. The amount of green leaf area (indexed using satellite-derived estimates of fractional interception of photosynthetically active radiation fAPAR), and the timing and magnitude of rainfall events, were the two most important predictors used in the ANN model. These drivers were also identified by multiple linear models (MLR), with strong interactive effects. The annual integral of the filled NEE data was found to range from −138 to +155 g C/m2/y over the 5 year eddy covariance measurement period. When applied to a 25 year time series of meteorological data, the ANN model predicts an annual mean NEE of 75 (±105) g C/m2/y. The main correlates of this inter-annual variability were found to be variation in the amount of absorbed photosynthetically active radiation (APAR), length of the growing season, and number of days in the year when moisture was available in the soil.

scholarly journals GROUNDWATER QUALITY ASSESSMENT FOR DRINKING PURPOSE IN BADHRA BLOCK, CHARKHI DADRI DISTRICT, HARYANA, INDIA

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Anup Kumar ◽  
Himanshu Himanshu ◽  
V.S. Arya
Keyword(s):  
Groundwater Quality ◽  
Arid Regions ◽  
Total Dissolved Solids ◽  
Residual Chlorine ◽  
Dissolved Solids ◽  
Water Testing ◽  
Groundwater Samples ◽  
Nitrite Nitrate ◽  
Semi Arid ◽  
Drinking Purpose

Water is important for survival of living beings and non-living developmental activities. In the present developmental scenario requirement of water is increasing very fast. In arid to semi-arid regions groundwater is very important for fulfilling the need of people. Badhra block is falling in Charkhi Dadri district of Haryana state, India. The climate of the block is semi-arid. Groundwater is the main source for drinking and irrigation purpose. In the study area ten groundwater samples were collected in the month of January, 2019. Groundwater samples were analyzed using field water testing kit prepared by Tamilnadu Water Supply and Drainage Board, Chennai for twelve chemical parameters-pH, alkalinity, hardness, chloride, total dissolved solids, fluoride, iron, nitrite, nitrate, ammonia, phosphate and residual chlorine. In the groundwater samples pH varies from 7 to 7.5, alkalinity 250-450 mg/l,hardness 70 - 580 mg/l,chloride 60-600 mg/l, total dissolved solids (TDS) 564-1704 mg/l, fluoride 0.5-3 mg/l, iron nil in all groundwater samples, ammonia nil to 1 mg/l, nitrite 0.2- 0.5 mg/l, nitrate 45-75mg/l, phosphate nil to 0.5 mg/l, residual chlorine nil in all ten groundwater samples. Groundwater is potable in one sample taken at Dalawas and non-potable in nine groundwater samples taken at Lad (fluoride 2 mg/l, ammonia 1mg/l, nitrate 75mg/l), Badhara (fluoride 3mg/l), Kari (nitrate 75mg/l), Sisrli (nitrate 75mg/l), Dandma (nitrate 75mg/l), Jeoli (nitrite 75 mg/l), Mandi (nitrate 75 mg/l), Rahrodi (nitrate 75mg/l), Dohka (nitrate 75mg/l). The study is highly useful for monitoring of groundwater quality for drinking purpose.

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