scholarly journals Rehabilitation of Degraded Tropical Rainforest Using Dipterocarp Trees in Sarawak, Malaysia

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Hattori Daisuke ◽  
Kenzo Tanaka ◽  
Kendawang Joseph Jawa ◽  
Ninomiya Ikuo ◽  
Sakurai Katsutoshi
Keyword(s):  
Light Intensity ◽  
Seedling Growth ◽  
Secondary Forest ◽  
Seedling Survival ◽  
High Light Intensity ◽  
High Light ◽  
Degraded Land ◽  
Growth And Survival ◽  
Seedling Growth Rate ◽  
Logged Forest

To develop rehabilitation planting techniques in tropical degraded forests, we investigated (1) basic soil characteristics and light conditions; (2) growth and survival of seven dipterocarp seedlings over 81 months; and (3) the effect of environmental factors on the survival of seedlings grown in three degraded vegetations (grassland, secondary forest, and logged forest) in Sarawak, Malaysia. The soil was weakly acidic, and kaolin minerals dominated. The amount of exchangeable bases in surface soils, soil temperature (>35°C), and relative light intensity were all highest in the grassland. Seedling growth was also highest in the grassland, whereas many seedlings died there over 81 months. Growth and survivability were very similar in secondary and logged forests. The death of the seedlings in the grassland was attributable to an extremely high light intensity for all species. In contrast, the seedling growth rate in all species was also enhanced by light intensity. In conclusion, dipterocarp seedlings can be planted on highly degraded land such as grassland, although high light intensity limits their survival. Planting under nurse trees such as regenerated pioneer trees may be an effective method to enhance seedling survival under open conditions such as grassland.

The effect of seed size on seedling growth in subterranean clover (Trifolium subterraneum L.)

1972 ◽  
Vol 23 (4) ◽  
pp. 595 ◽  
Author(s):  
GB Taylor
Keyword(s):  
Light Intensity ◽  
Seed Size ◽  
Seedling Growth ◽  
Subterranean Clover ◽  
High Light Intensity ◽  
High Light ◽  
Plant Weight ◽  
Trifoliate Leaf ◽  
Relative Growth ◽  
Leaf Stage

The effect of seed size on seedling growth in a single population of Daliak subterranean clover was studied by growing individually weighed seeds to the third trifoliate leaf stage in three controlled environments. The environments were: 18°C at high light intensity (27,000 lux), 12° at high light intensity, and 18° at low light intensity (5400 lux). Plant weight at emergence exceeded the weight of embryo in the original seed, owing in part to the utilization of endosperm. At emergence the ratio of plant weight to seed weight increased with increasing seed size. Nevertheless, in all environments the smaller seeds ultimately produced relatively larger plants owing to a higher relative growth rate, particularly during the cotyledon and unifoliate leaf stage of growth. Higher relative growth rates in seedlings from smaller seeds were associated with higher leaf area ratios resulting from the production of relatively larger cotyledon and individual leaf areas in all environments. More rapid leaf expansion in seedlings from larger seeds progressively offset this advantage.

Characteristics of Photosynthesis in Different Wheat Cultivars under High Light Intensity and High Temperature Stresses

2009 ◽  
Vol 34 (12) ◽  
pp. 2196-2201 ◽  
Author(s):  
Xue-Li QI ◽  
Lin HU ◽  
Hai-Bin DONG ◽  
Lei ZHANG ◽  
Gen-Song WANG ◽  
...  
Keyword(s):  
High Temperature ◽  
Light Intensity ◽  
High Light Intensity ◽  
High Light ◽  
Wheat Cultivars ◽  
Temperature Stresses

High light intensity stress as the limiting factor in micropropagation of sugar maple (Acer saccharum Marsh.)

2017 ◽  
Vol 129 (2) ◽  
pp. 209-221 ◽  
Author(s):  
Amritpal S. Singh ◽  
A. Maxwell P. Jones ◽  
Mukund R. Shukla ◽  
Praveen K. Saxena
Keyword(s):  
Light Intensity ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
High Light Intensity ◽  
High Light ◽  
Limiting Factor ◽  
Intensity Stress

Predator Detection is Limited in Microhabitats with High Light Intensity: An Experiment with Brown-Headed Cowbirds

Ethology ◽  
2012 ◽  
Vol 118 (4) ◽  
pp. 341-350 ◽  
Author(s):  
Esteban Fernández-Juricic ◽  
Marcella Deisher ◽  
Amy C. Stark ◽  
Jacquelyn Randolet
Keyword(s):  
Light Intensity ◽  
High Light Intensity ◽  
High Light ◽  
Predator Detection

Environmental Influence on the Tolerance of Corn to Atrazine

Weed Science ◽  
1970 ◽  
Vol 18 (4) ◽  
pp. 509-514 ◽  
Author(s):  
Lafayette Thompson ◽  
F. W. Slife ◽  
H. S. Butler
Keyword(s):  
Zea Mays ◽  
High Temperature ◽  
Low Temperature ◽  
Light Intensity ◽  
Environmental Influence ◽  
High Light Intensity ◽  
High Light ◽  
Growth Chamber ◽  
Peptide Conjugates ◽  
Before And After

Corn(Zea maysL.) in the two to three-leaf stage grown 18 to 21 days in a growth chamber under cold, wet conditions was injured by postemergence application of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) plus emulsifiable phytobland oil. Injury was most severe when these plants were kept under cold, wet conditions for 48 hr after the herbicidal spray was applied, followed by exposure to high light intensity and high temperature. Under these growth chamber conditions, approximately 50% of the atrazine-treated plants died. Since wet foliage before and after application increased foliar penetration and low temperature decreased the rate of detoxication to peptide conjugates, atrazine accumulated under cold, wet conditions. This accumulation of foliarly-absorbed atrazine and the “weakened” conditions of the plants grown under the stress conditions is believed to be responsible for the injury to corn. Hydroxylation and the dihydroxybenzoxazin-3-one content in the roots were reduced at low temperature, but it is unlikely that this contributed to the death of the corn.

scholarly journals Effects of alkalinity and salinity at low and high light intensity on hydrogen isotope fractionation of long-chain alkenones produced by <i>Emiliania huxleyi</i>

2017 ◽  
Vol 14 (24) ◽  
pp. 5693-5704 ◽  
Author(s):  
Gabriella M. Weiss ◽  
Eva Y. Pfannerstill ◽  
Stefan Schouten ◽  
Jaap S. Sinninghe Damsté ◽  
Marcel T. J. van der Meer
Keyword(s):  
Light Intensity ◽  
Environmental Conditions ◽  
Hydrogen Isotope ◽  
Isotope Fractionation ◽  
Emiliania Huxleyi ◽  
High Light Intensity ◽  
High Light ◽  
Light Conditions ◽  
Low Light ◽  
Long Chain

Abstract. Over the last decade, hydrogen isotopes of long-chain alkenones have been shown to be a promising proxy for reconstructing paleo sea surface salinity due to a strong hydrogen isotope fractionation response to salinity across different environmental conditions. However, to date, the decoupling of the effects of alkalinity and salinity, parameters that co-vary in the surface ocean, on hydrogen isotope fractionation of alkenones has not been assessed. Furthermore, as the alkenone-producing haptophyte, Emiliania huxleyi, is known to grow in large blooms under high light intensities, the effect of salinity on hydrogen isotope fractionation under these high irradiances is important to constrain before using δDC37 to reconstruct paleosalinity. Batch cultures of the marine haptophyte E. huxleyi strain CCMP 1516 were grown to investigate the hydrogen isotope fractionation response to salinity at high light intensity and independently assess the effects of salinity and alkalinity under low-light conditions. Our results suggest that alkalinity does not significantly influence hydrogen isotope fractionation of alkenones, but salinity does have a strong effect. Additionally, no significant difference was observed between the fractionation responses to salinity recorded in alkenones grown under both high- and low-light conditions. Comparison with previous studies suggests that the fractionation response to salinity in culture is similar under different environmental conditions, strengthening the use of hydrogen isotope fractionation as a paleosalinity proxy.

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