scholarly journals Effects of light availability on leaf attributes and seedling growth of four tree species in tropical dry forest

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Sachchidanand Tripathi ◽  
Rahul Bhadouria ◽  
Pratap Srivastava ◽  
Rajkumari S. Devi ◽  
Ravikant Chaturvedi ◽  
...  

Abstract Background In tropical dry forests, variation in understory light availability due to season and canopy tree density could be a governing factor in establishment and growth of tree seedlings. Species with varying life history traits are expected to respond differentially to such heterogeneity. We investigated the response of seedlings of four tree species in a tropical day forest in relation to spatiotemporal variability of light. We attempt to explore the role of leaf attributes in explaining intra- and inter-specific variations in relative growth rate. Four study sites, each with three contrasting canopy conditions, were selected along a soil moisture gradient. Seedlings of four tree species (viz., Acacia catechu, Bridelia retusa, Lagerstroemia parviflora, and Shorea robusta), varying in life history traits, were monitored for seasonal variations in growth traits across canopy condition and sites for 2 years. Results We observed a larger variation in leaf attributes for pioneer species. A. catechu showed highest mean values for leaf dry matter content, leaf nitrogen concentration, leaf phosphorus concentration, net stomatal conductance, net photosynthetic rate, and relative growth rate in high light conditions. S. robusta and B. retusa demonstrated highest mean values for all the leaf attributes (except leaf dry matter content) in low light conditions. However, intermediate values for leaf attributes were observed in L. parviflora which preferred moderate light conditions. Conclusions Seasonal variations in light availability at the forest floor appear to play an important role in the establishment and growth of tree seedlings in seasonal dry forests. Leaf attributes can be used to explain intra- and inter-specific variation in response to light availability. Leaf attributes in combinations can be used to predict relative growth rate of tree species in tropical dry environment, which apart from soil moisture is also determined by light availability due to seasonal changes and canopy tree density.

2011 ◽  
Vol 27 (6) ◽  
pp. 611-620 ◽  
Author(s):  
Wenjie Yang ◽  
Fude Liu ◽  
Lingyan Zhou ◽  
Shiting Zhang ◽  
Shuqing An

Abstract:We performed a pot experiment in which 540 seedlings of nine non-pioneer light-demanding tree species were grown for 12 months in shade houses at three light levels, 46% daylight, 13% daylight and 2% daylight, to examine the mechanisms contributing to the coexistence of seedlings of non-pioneer light-demanding tree species in secondary successional tropical rain forest in Hainan, China. Growth and survival of tree seedlings were compared at different light levels, and the morphological and physiological correlates of high-light seedling growth and low-light survival across species were determined. For all species, mortality was very low in the 46% daylight and 13% daylight treatment but increased significantly in the 2% daylight treatment. Seedling survival in 2% daylight treatment was positively related to seed mass. Trade-off between high-light growth and low-light survival was more evident in the relationship with 2% daylight treatment as compared with 13% daylight treatment. Relative growth rate in the 2% daylight treatment was not significantly related to relative growth rate in the 13% daylight or 46% daylight treatment; although a slight negative correlation was apparent. Interspecific variation in RGRm was only closely correlated with net assimilation rate (NAR). The results provide some support for the niche-partitioning hypothesis.


1980 ◽  
Vol 10 (1) ◽  
pp. 35-41 ◽  
Author(s):  
R. E. Farmer Jr.

Classical growth analysis was used to examine the basis of major variation in seedling growth characteristics among and within six deciduous tree species in nursery beds. A combination of high investment in leaf area and substantial net assimilation rate accounted for the high relative growth rate of Liriodendrontulipifera L. and Prunusserotina Ehrh.; these species also produced the largest seedlings in the test. Final weight of four Quercus species was closely associated with initial leaf area established at germination; Q. rubra L. and Q. prinus L. had the largest seedlings despite having net assimilation rates lower than Q. alba L. and Q. ilicifolia Wangenh., the smallest seedlings in the test. Within species, relative growth rate was significantly correlated with both net assimilation rate and relative growth rate of leaf area. Leaf area partition coefficient was positively correlated with relative growth rate in L. tulipifera, P. serotina, and Q. rubra but not in Q. alba, Q. prinus, and Q. ilicifolia.


2006 ◽  
Vol 22 (6) ◽  
pp. 653-661 ◽  
Author(s):  
E. Khurana ◽  
J. S. Singh

Seedling growth under three shade levels was studied at Varanasi, India, for five tree species of tropical dry forest, which differed in life-history traits. Three of these were small-seeded pioneer (Albizia procera, Acacia nilotica and Phyllanthus emblica) and the other two were large-seeded non-pioneer (Terminalia arjuna and Terminalia chebula) species. Seedlings of all the species were subjected to three light levels (80–100%, 20–30% and 3–7% of full sunlight) comparable to sunlit gaps and shaded microsites in the dry forest. After 4 mo of shade treatment, height, basal area, biomass and other growth traits, viz. RGR (relative growth rate), NAR (net assimilation rate), and SLA (specific leaf area) were determined. Etiolation and plasticity indices were calculated. Reduction in seedling height, biomass and relative growth rates and enhancement in SLA due to shade was greater for small-seeded pioneer species. Seedlings from large-seeded non-pioneer species exhibited a stronger etiolation response to shade than seedlings from small-seeded species. Phenotypic plasticity indices for basal area, plant biomass and relative growth rate were greater for the three small-seeded early successional species (A. procera, A. nilotica and P. emblica), indicating their specialization in a more favourable light environment such as large gaps and forest peripheries. The non-pioneer and pioneer species differed only in the degree of shade tolerance, and we suggest that dry forest species cannot be strictly categorized into two distinct groups (shade tolerant vs. intolerant), rather shade preference and gap preference would be the more expressive terms. Marked environmental heterogeneity in terms of irradiance and the phenology of dry tropical trees permits coexistence of species of varying ecological traits, contributing to the maintenance of diversity in the dry forest.


2021 ◽  
Vol 19 (6) ◽  
pp. 1-10
Author(s):  
Nisa Leksungnoen ◽  
◽  
Suwimon Uthairatsamee ◽  
Tushar Andriyas ◽  
◽  
...  

Rosewood and Teak are valuable timber species, which have been heavily logged from both natural forests and plantations. Climate change has also contributed to a reduction in their numbers. We studied their light adaptability at the seedling stage to quantify the growth and physiological characteristics under 10% and 100% of full sunlight. Rosewood performed better, as indicated by the relative growth rate, chlorophyll content, and chlorophyll efficiency, under both shade and sunlight. We also simulated a sudden change in light intensity (gap opening up in the canopy) by exposing seedlings, previously under shade, to full sunlight. Rosewood seedlings responded faster (higher relative growth rate) to changing light conditions relative to Teak. We conclude that Rosewood seedlings can be planted either under shade, or in full sunlight, or in a location experiencing sudden change from shade to sunlight, while Teak seedlings should be planted under at least 10% sunlight, but not in full sunlight, as it can lead to chlorophyll and tissue damage.


2014 ◽  
Vol 114 (2) ◽  
pp. 315-324 ◽  
Author(s):  
Kyle W. Tomlinson ◽  
Lourens Poorter ◽  
Frans Bongers ◽  
Fabian Borghetti ◽  
Loes Jacobs ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document