Predictions of Soil-Water Potentials in the North-Western Sonoran Desert

1986 ◽  
Vol 74 (1) ◽  
pp. 143 ◽  
Author(s):  
Donald R. Young ◽  
Park S. Nobel
Keyword(s):  
Soil Water ◽  
Sonoran Desert ◽  
The North ◽  
Water Potentials ◽  
North Western

Photosynthetic Responses of Three Codominant Species from the North-western Sonoran Desert - a C3 Deciduous Sub-shrub, a C4 Deciduous Bunchgrass, and a CAM Evergreen Leaf Succulent

1997 ◽  
Vol 24 (6) ◽  
pp. 787 ◽  
Author(s):  
Park S. Nobel ◽  
Hehui Zhang
Keyword(s):  
Leaf Area ◽  
Sonoran Desert ◽  
Summer Rainfall ◽  
Productivity Index ◽  
Annual Rainfall ◽  
Photon Flux ◽  
Co2 Uptake ◽  
The North ◽  
Net Co2 Uptake ◽  
North Western

To investigate seasonal and annual influences of environmental conditions on leaf net CO2 uptake (A), three codominant species from the north-western Sonoran Desert differing in photosynthetic pathway and leaf phenology were examined: the C3 deciduous sub-shrub Encelia farinosa, the C4 deciduous bunchgrass Pleuraphis rigida, and the CAM evergreen leaf succulent Agave deserti. To allow interspecific comparisons and to predict field responses from 1974 through 1995, an environmental productivity index (EPI) model previously developed for CAM plants was used, which scaled the responses of A to water, temperature, and photosynthetic photon flux (PPF) over 24-h periods to individual dimensionless values. The net CO2 uptake predicted using the EPI approach agreed well with field measurements. Agave deserti was the most drought-tolerant and E. farinosa was the least; the optimum day/night air temperatures and the PPF requirement for A were highest for P. rigida and lowest for A. deserti. For 1974 through 1995, daily EPI averaged over a year was highest for E. farinosa, indicating that it operates closest to its photosynthetic optimum. However, the predicted A was highest for P. rigida. Variations in A were annually bimodal, with the greatest differences among the three species in wet years. Afor all three species increased linearly as annual rainfall increased. Leaf area per plant for E. farinosa was highest in the winter and early spring and did not respond appreciably to summer rainfall; leaf area for P. rigida was also highest in the winter. For the evergreen A. deserti, which based on ground cover is the dominant species at the field site, new leaves unfolded in response to both winter and summer rainfall but most photosynthetic area was contributed by older leaves, leading to the highest annual plant net CO2 uptake.

scholarly journals PLASTIC TUNELL ORIENTATION AND IRRIGATION MANAGEMENT OF PEPPER (Capsicum annuum, L.)

Irriga ◽  
2003 ◽  
Vol 8 (1) ◽  
pp. 69-77
Author(s):  
Marcos Brandão Braga ◽  
Antonio Evaldo Klar
Keyword(s):  
Soil Water ◽  
Capsicum Annuum ◽  
Irrigation Management ◽  
Maximum Temperature ◽  
External Temperature ◽  
Class A ◽  
Capsicum Annuum L ◽  
The North ◽  
Water Potentials ◽  
East West

PLASTIC TUNELL ORIENTATION AND IRRIGATION MANAGEMENT OF PEPPER(Capsicum annuum, L.)  Marcos Brandão Braga Antonio Evaldo Klar*Department of Agricultural Engineering, College of Agricultural Sciences, State University of São Paulo, P.O. 237, CEP 18603-970, Botucatu – SP. E-mail: [email protected]*Scientific Researchist of CNPq.  1 ABSTRACT  The main purpose of this study was to measure spatial distribution of evaporation and pepper plant (Capsicum annuum, L.) behavior under five minimum soil water potentials (-10, -20, -30, -40 and –50 kPa) in two arch roof plastic tunnels (20m length x 5m width x 4m height in the center), oriented to North/South and East/West. Small evaporimeters were installed in each tunnel, with intervals of 1.2m in the width and 3.0m in the length directions and 0.5 and 1.0m from the soil surface. Thermohygrographes and Class A Pans were used in both tunnels and outside. The best fruit yields were obtained from the highest soil water potentials and for plants from East/West tunnel (1.62 kg/plant) while North/South produced only 1.42 kg/plant. Consequently, tunnels constructed on the East/West direction are indicated for higher pepper yield and it also showed more homogeneous spatial evaporation distribution than the North/South one. The geostatistical studies did not showed spatial dependency of the evaporation from microevaporimeters in both tunnels. The evaporation averages of Class A Pan in the North/South and East/West tunnels were 32.02 and 36.46% lower than outside, respectively. The minimum and maximum temperature averages were not significantly different in both tunnels, but the minimum external temperature average were higher and the maximum average was lower than that obtained in the tunnels. Air relative humidity averages in both tunnels were 9,1% higher than outside.  KEYWORDS: plastic tunnels; pepper; evaporation.  BRAGA, M. M.; KLAR, A. E. INFLUÊNCIA DA ORIENTAÇÃO DE ESTUFAS E MANEJO DE IRRIGAÇÃO NA CULTURA DE PIMENTÃO (Capsicum annuum, L.)  2 RESUMO  O principal objetivo deste estudo foi medir a distribuição espacial da evaporação dentro de duas estufas tipo túnel com posições geográficas Norte/Sul e Leste/Oeste e também a produção de pimentão (Capsicum annuum, L.) irrigado por gotejamento. O delineamento estatístico foi em blocos casualizados e cinco tratamentos de potencial mínimo de água no solo (-10, -20, -30, - 40 e -50 kPa). Microevaporímetros foram instalados em cada estufa em intervalos de 1,2m no sentido da largura e3m no sentido do comprimento da estufa e em duas alturas 0,5 e 1m do solo, formando uma rede de 24 evaporímetros por estufa. Termigrógrafos e tanques Classe A foram usados dentro e fora das estufas. A melhor produção foi obtida no manejo feito com o maior potencial de água no solo em ambas as estufas, com as medias de produção de 1,62 kg/planta na estufa com orientação Leste/Oeste e de 1,42kg/planta no Norte/Sul, estatisticamente diferentes, mostrando que o pimentão produzido na estufa instalada na posição Leste/Oeste seria a indicada para produção comercial nas condições estudadas. As médias de evaporação nos tanques Classe A nas estufas Norte/Sul e Leste/Oeste foram 32,02 e 36,46%, respectivamente, menores que a evaporação do instalado externamente. As médias das mínimas e máximas temperaturas não foram significativamente diferentes entre estufas, mas as mínimas temperaturas externas foram mais altas e as máximas mais baixas que as obtidas dentro das estufas. As médias da umidade relativa em ambas estufas foram 9,1% maiores que as externas. Os resultados mostraram maior homogeneidade na distribuição espacial da evaporação na estufa Leste/Oeste que na Norte/Sul. Os estudos de geoestatística não mostraram dependência espacial entre os pontos de evaporação medidos em ambas as estufas.  UNITERMOS: Estufas, Pimentão, Evaporação.

scholarly journals ORIENTAÇÃO GEOGRÁFICA DE ESTUFAS DE POLIETILENO E POTENCIAIS DE ÁGUA NO SOLO NO CULTIVO DO MELÃO RENDILHADO HÍBRIDO 'NERO'

Irriga ◽  
2006 ◽  
Vol 11 (1) ◽  
pp. 130-138 ◽  
Author(s):  
Marcos Brandão Braga ◽  
Luiza Helena Duenhas ◽  
Cláudio Márcio Pereira de Souza ◽  
Antônio Evaldo Klar
Keyword(s):  
Water Potential ◽  
Soil Water ◽  
Cucumis Melo ◽  
Irrigation Management ◽  
Soil Water Potential ◽  
Fruit Weight ◽  
The North ◽  
Water Potentials ◽  
Tunnel Positions ◽  
East West

ORIENTAÇÃO GEOGRÁFICA DE ESTUFAS DE POLIETILENO E POTENCIAIS DE ÁGUA NO SOLO NO CULTIVO DO MELÃO RENDILHADO HÍBRIDO 'NERO'  Marcos Brandão Braga; Luiza Helena Duenhas; Cláudio Márcio Pereira De Souza; Antônio Evaldo Klar[1] Departamento de Engenharia Rural,  Faculdade de Ciências Agroômicas/UNESP, Botucatu, SP,  [email protected] Embrapa Semi Árido,Petrolina, PE3 Fafeid, Diamantina, MG4 Departamento de Engenharia Rural, Faculdade de Ciências Agroômicas /UNESP,  Botucatu, SP   1 RESUMO O presente estudo teve como objetivo verificar os efeitos de duas orientações de estufas (Norte-Sul e Leste-Oeste) e diferentes potenciais de água no solo (-30, -40, -50 e -70 kPa) sobre o peso individual e produtividade de frutos de melão rendilhado híbrido Nero (Cucumis melo reticulatus). Observou-se que, de maneira geral na estufa com orientação Leste/Oeste, obtiveram-se as maiores produções bem como frutos de maior peso que na estufa com orientação Norte/Sul. As maiores produções foram obtidas com potenciais mínimos de água no solo de -30 e -40 kPa . UNITERMOS– (melão), Cucumis melo reticulatus, (produção), irrigação, estufas, potenciais de água no solo.  BRAGA, M. B.; DUENHAS, L. H.; SOUZA, C. M. P. de; KLAR, A. E.PLASTIC TUNNEL GEOGRAPHIC ORIENTATION AND SOIL WATER POTENTIAL ON IRRIGATION MANAGEMENT OF NET MELON CROP This study aimed to verify the effects of four different minimum soil water potentials (-30, -40, -50 e -70 kPa) and two different plastic tunnel positions (North-South and East-West) on net melon yield. The results showed that in the East-West position the yield and fruit weight were higher than in the North-South position. The highest yields of melon crop were obtained from  -30 kPa. to -40 kPa minimum soil water potential. KEYWORDS – Cucumis melo reticulatus ,  plastic tunnel, soil water potential

U-Pb on Zircon and Monazite Geochronology of Granites of the Zhytomyr and Sheremetiv Complexes, the North-Western Region of the Ukrainian Shield

2018 ◽  
Vol 40 (2) ◽  
pp. 63-85 ◽  
Author(s):  
L. Shumlyanskyy ◽  
L. Stepanyuk ◽  
S. Claesson ◽  
K. Rudenko ◽  
A. Bekker
Keyword(s):  
Ukrainian Shield ◽  
Western Region ◽  
The North ◽  
North Western

Assessment of the Reactions of Algal Communities to Influence of Climatic Factors in the North-Western Black Sea Ecosystem

2018 ◽  
Vol 20 (2) ◽  
pp. 121-134 ◽  
Author(s):  
G. G. Minicheva ◽  
V. N. Bolshakov ◽  
E. S. Kalashnik ◽  
A. B. Zotov ◽  
A. V. Marinets
Keyword(s):  
Black Sea ◽  
Climatic Factors ◽  
Algal Communities ◽  
The North ◽  
North Western
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