scholarly journals Opinion paper: Effects of simulated soil temperature on stem diameter increment of Pinus cembra at the alpine timberline: a new approach based on root zone roofing

2009 ◽  
Vol 129 (2) ◽  
pp. 141-144 ◽  
Author(s):  
A. Gruber ◽  
G. Wieser ◽  
W. Oberhuber
Keyword(s):  
Soil Temperature ◽  
Root Zone ◽  
Stem Diameter ◽  
Pinus Cembra ◽  
New Approach ◽  
Diameter Increment ◽  
Alpine Timberline

Phenology and Stem Diameter Increment Seasonality in a Costa Rican Wet Tropical Forest

Biotropica ◽  
2007 ◽  
Vol 40 (2) ◽  
pp. 151-159 ◽  
Author(s):  
Joseph J. O'Brien ◽  
Steven F. Oberbauer ◽  
David B. Clark ◽  
Deborah A. Clark
Keyword(s):  
Tropical Forest ◽  
Costa Rican ◽  
Stem Diameter ◽  
Diameter Increment

scholarly journals A New Approach for Planning M.C.W.H. Systems with Annual Rainfall-Runoff Data

2019 ◽  
Author(s):  
Spyros Giakoumakis ◽  
Alexis Skalieris
Keyword(s):  
Arid Regions ◽  
Root Zone ◽  
Aegean Sea ◽  
Annual Rainfall ◽  
Water Harvesting ◽  
Rainfall Runoff ◽  
Zero Energy ◽  
New Approach ◽  
Aegean Islands ◽  
Linear Relationships

In the present study a new approach for planning Micro-Catchment Water Harvesting (M.C.W.H.) systems for irrigation in semi-arid regions such as the Aegean islands, is presented. This is a cheap solution for constructing infrastructure with zero energy cost in regions where water is scarce. The proposed approach introduces simple linear relationships for estimating the annual volume of water Vs collected mainly from the CA (Contributing Area), stored in the root zone (Infiltration Basin, IB), according to the annual  rainfall and runoff depths, after having determined the ratio of areas of micro-catchment components, i.e., λ = ΑCA/ΑΙΒ and its whole area AMC This procedure was applied in Paros island of the Cyclades complex in the middle of the Aegean sea in east Mediterranean. Besides, income-cost analysis was performed via NPV method for almonds, peach and apricot trees.

scholarly journals Impacts of changes in vegetation cover on soil water heat coupling in an alpine meadow of the Qinghai-Tibet Plateau, China

2009 ◽  
Vol 13 (3) ◽  
pp. 327-341 ◽  
Author(s):  
W. Genxu ◽  
H. Hongchang ◽  
L. Guangsheng ◽  
L. Na
Keyword(s):  
Heat Flux ◽  
Soil Temperature ◽  
Soil Water ◽  
Vegetation Cover ◽  
Alpine Meadow ◽  
Root Zone ◽  
Frozen Soil ◽  
Tibet Plateau ◽  
Permafrost Region ◽  
Qinghai Tibet Plateau

Abstract. Alpine meadow is one of the most widespread grassland types in the permafrost regions of the Qinghai-Tibet Plateau, and the transmission of coupled soil water heat is one of the most crucial processes influencing cyclic variations in the hydrology of frozen soil regions, especially under different vegetation covers. The present study assesses the impact of changes in vegetation cover on the coupling of soil water and heat in a permafrost region. Soil moisture (θv), soil temperature (Ts), soil heat content, and differences in θv−Ts coupling were monitored on a seasonal and daily basis under three different vegetation covers (30, 65, and 93%) on both thawed and frozen soils. Regression analysis of θv vs. Ts plots under different levels of vegetation cover indicates that soil freeze-thaw processes were significantly affected by the changes in vegetation cover. The decrease in vegetation cover of an alpine meadow reduced the difference between air temperature and ground temperature (ΔTa−s), and it also resulted in a decrease in Ts at which soil froze, and an increase in the temperature at which it thawed. This was reflected in a greater response of soil temperature to changes in air temperature (Ta). For ΔTa−s outside the range of −0.1 to 1.0°C, root zone soil-water temperatures showed a significant increase with increasing ΔTa−s; however, the magnitude of this relationship was dampened with increasing vegetation cover. At the time of maximum water content in the thawing season, the soil temperature decreased with increasing vegetation. Changes in vegetation cover also led to variations in θv−Ts coupling. With the increase in vegetation cover, the surface heat flux decreased. Soil heat storage at 20 cm in depth increased with increasing vegetation cover, and the heat flux that was downwardly transmitted decreased. The soil property varied greatly under different vegetation covers, causing the variation of heat conductivity and water-heat hold capacity in topsoil layer in different vegetation cover. The variation of heat budget and transmitting in soil is the main factor that causes changes in soil thawing and freezing processes, and θv−Ts coupling relationship under different vegetation fractions. In addition to providing insulation against soil warming, vegetation in alpine meadows within the permafrost region also would slow down the response of permafrost to climatic warming via the greater water-holding capacity of its root zone. Such vegetation may therefore play an important role in conserving water in alpine meadows and maintaining the stability of engineering works constructed within frozen soil of the Qinghai-Tibet Plateau.

Soil Temperature and Maize Nitrogen Uptake Improvement Under Partial Root-Zone Drying Irrigation

Pedosphere ◽  
2016 ◽  
Vol 26 (6) ◽  
pp. 872-886 ◽  
Author(s):  
Fatemeh KARANDISH ◽  
Ali SHAHNAZARI
Keyword(s):  
Soil Temperature ◽  
Nitrogen Uptake ◽  
Root Zone

scholarly journals Effect of the density or red pine stands on moisture supply in sanpy soils.

1962 ◽  
Vol 10 (3) ◽  
pp. 235-239
Author(s):  
M.L. De Vries ◽  
S.A. Wilde
Keyword(s):  
Moisture Content ◽  
Root Zone ◽  
Field Capacity ◽  
Red Pine ◽  
Pine Plantation ◽  
High Moisture ◽  
Growing Stock ◽  
Diameter Increment ◽  
Weed Growth ◽  
Absorbing Roots

The moisture content was determined periodically (April to November) in non-podzolic outwash sand supporting a 17-year-old fully stocked red-pine plantation and in parts of the same plantation reduced 50 % by thinning. The diameter increment of average trees was recorded by ring-band dendro-meters. The water supply in the 4-ft root zone of thinned plantations averaged nearly 10% or 500 tons/acre. This soil gained moisture from rainfall during the critical midsummer period. Soil of the fully-stocked stand had a high moisture content early in the growing season because of a delayed thaw. Early in July, decrease in moisture below the field capacity of 7% coincided with retarded diameter growth of trees, probably because of restricted capillary transfer and moisture depletion in the vicinity of absorbing roots. 50% thinning reduced the growing stock beyond permissible limits and was favourable to weed growth. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Effect of polythene pot thickness on seedling growth of Chrysophyllum albidum G. Don (Ericales: Sapotaceae)

2019 ◽  
Vol 6 (13) ◽  
pp. 359-365
Author(s):  
M. O. Ojo ◽  
T. Adeniran
Keyword(s):  
Soil Temperature ◽  
Plant Height ◽  
Analysis Of Variance ◽  
Growth Parameters ◽  
Block Design ◽  
Stem Diameter ◽  
Tree Seedlings ◽  
Recorded Data ◽  
Number Of Leaves ◽  
Level Of Significance

The study investigated the response of tree seedlings to different pot thickness. Chrysophyllum albidum G. Don (Ericales: Sapotaceae) seedlings were subjected to four treatments, T1 = 0.01 mm pot polythene thickness, T2 = 0.02 mm polythene pot thickness, T3 = 0.03 mm polythene pot thickness, T4 = 0.04 mm pot polythene thickness, 0.01 mm served as control. There were four treatments replicated five times making a total of twenty seedlings altogether. The experiment was arranged in Randomized Complete Block Design (RCBD). Growth parameters assessed fortnightly were plant height (cm), stem diameter (mm) and number of leaves. Soil temperature of each treatment at different time intervals were also monitored and recorded. Data recorded were analyzed using descriptive statistics and analysis of variance (ANOVA). The result showed that T1 had the best performance in terms of plant height and stem diameter while equal number of leaves were recorded in all the treatments. Analysis of variance (ANOVA) showed that there were no significant differences among treatments at 5% level of significance. This indicates that polythene pot thickness of 0.01 mm-0.04 mm can be used to raise C. albidum seedlings at the nursery stage. Soil temperature increases with polythene pot thickness. Hence, T4 gave the highest soil temperature of 36.7 oC. Soil temperature and seedlings growth increases with polythene pots thickness. For optimum growth and development of C. albidum seedlings in the nursery 0.01 mm polythene pot should be used.

scholarly journals Bell Pepper (Capsicum annum L.) under Colored Shade Nets: Plant Growth and Physiological Responses

HortScience ◽  
2019 ◽  
Vol 54 (10) ◽  
pp. 1795-1801 ◽  
Author(s):  
Juan Carlos Díaz-Pérez ◽  
Kelly St. John
Keyword(s):  
Gas Exchange ◽  
Plant Growth ◽  
Antioxidant Capacity ◽  
Root Zone ◽  
Leaf Gas Exchange ◽  
Leaf Temperature ◽  
Stem Diameter ◽  
Bell Pepper ◽  
Fresh Weight ◽  
Total Carotenoids

Use of colored shade nets has shown benefits in bell pepper and other horticultural crops. There is still, however, limited information on plant growth and physiology of bell pepper crop grown under colored shade nets. The objective was to determine the effects of colored shade nets on plant growth, leaf gas exchange, and leaf pigments of field-grown bell pepper. Experimental design was a randomized complete block with four replications and five shade treatments (black, red, silver, and white nets, and an uncovered control). Mean and maximal air temperature and midday root zone temperature (RZT) were highest in the unshaded treatment. Differences in air temperatures between shade net treatments were smaller compared with the differences in RZT between treatments. Plant fresh weight and stem diameter were reduced in the unshaded treatment, and there were no plant fresh weight and stem diameter differences among shade nets. The incidence of Phytophthora blight (caused by Phytophthora capsici) was greatest in the unshaded treatment. Leaf stomatal conductance (gS) and photosystem II efficiency were reduced and leaf temperature increased in unshaded conditions. Leaf net photosynthesis, gS, internal CO2, and PSII efficiency decreased with increasing leaf temperature. Differences in leaf temperature among shade net treatments were because of differences in solar radiation captured by leaves. Leaf total carotenoids were lowest in unshaded conditions and there were no differences in total carotenoids among the shade nets. Chlorophyll a concentration and chlorophyll a/b ratio was lowest in unshaded conditions. Leaf total phenols, flavonoids, and cupric reducing antioxidant capacity (CUPRAC) values were highest in red net and in unshaded conditions. Trolox equivalent antioxidant capacity (TEAC) values were highest in red net and lowest in silver net. In conclusion, compared with unshaded conditions, shade nets resulted in improved bell pepper plant growth and leaf gas exchange. These responses were due primarily to the reduced leaf and root zone temperatures under shaded conditions, regardless of the color of shade net. The differences in plant growth and function due to color of shade net were inconsistent or minor for most of the plant variables measured.

Sign in / Sign up

Export Citation Format

Share Document