A 20-year tree liberation experiment in the Amazon: Highlights for diameter growth rates and species-specific management

Deforestation of tropical dry forest reduces soil fertility, with negative effects on future restoration intervention. To evaluate the effect of initial soil properties on three-year performance of six tree species in restoration settings, we measured C, N, and P contents in topsoils of 48 plots under minimal (exclusions of livestock grazing) and maximal (plantings of six native species) restoration intervention during two years in tropical dry forest in central Mexico. Survival and height and diameter relative growth rates were evaluated by species and by growth rank (three fast- and three slow-growing species). After two years, organic C and the C:N ratio increased early during natural succession; these increases might be related to high density of N2-fixing recruits at both intervention levels. Changes in N availability for plants (i.e., NO3− and NH4+ contents) occurred after cattle exclusion. After 40 months, the fast-growing legume Leucaena esculenta (DC.) Benth. had the highest survival (65.55%) and relative growth rate in both height (3.16%) and diameter (5.67%). Fast-growing species had higher survival and diameter growth rates than slow-growing species. Higher diameter growth rates for fast-growing species may be associated with a higher ability to forage for soil resources, whereas similar height growth rates for slow and fast-growing species suggested low competition for light due to slow natural succession at the site. Planted seedlings had higher survival possibly due to initial high NO3− content in the soil. Also, fast-growing species seem to benefit from initially higher pH in the soil. Both soil properties (i.e., pH and NO3−) may be augmented to favor the performance of fast-growing species in restoration plantings and to further accelerate soil recovery in tropical dry forests.

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Size dependent associations between tree diameter growth rates and functional traits in an Asian tropical seasonal rainforest

Functional Plant Biology ◽

10.1071/fp20226 ◽

2021 ◽

Vol 48 (2) ◽

pp. 231

Author(s):

Yu-Mei Yan ◽

Ze-Xin Fan ◽

Pei-Li Fu ◽

Hui Chen ◽

Lu-Xiang Lin

Keyword(s):

Functional Traits ◽

Tree Growth ◽

Growth Rates ◽

Small Diameter ◽

Diameter Growth ◽

Ontogenetic Shifts ◽

Size Classes ◽

Size Dependent ◽

Large Trees ◽

Leaf Economic Spectrum

Many studies focus on the relationships between plant functional traits and tree growth performances. However, little is known about the ontogenetic shifts of the relationships between functional traits and tree growth. This study examined associations between stem and leaf functional traits and growth rates and their ontogenetic shifts across 20 tropical tree species in a tropical seasonal rainforest in Xishuangbanna, south-west China. For each species, physiological active branches of individual trees belonged to three size classes (i.e. small, diameter at breast height (DBH) 5–10 cm; middle, DBH 10–20 cm; big, DBH >20 cm) were sampled respectively. We measured 18 morphological and structural traits, which characterised plant hydraulic properties or leaf economic spectrum. Associations between diameter growth rates and functional traits were analysed across three size classes. Our results revealed that diameter growth rates of big-sized trees were mainly related to traits related to plant hydraulic efficiency (i.e. theoretical hydraulic conductivity (Ktheo) and leaf vein density (Dvein)), which suggests that the growth of large trees is limited mainly by their xylem water transport capacity. For middle-sized trees, growth rates were significantly related to traits representing leaf economic spectrum (i.e. specific leaf area (SLA), individual leaf mass (ILM), palisade thickness (PT) and spongy thickness (SP)). Diameter growth rates of small-sized trees were not correlated with hydraulic or leaf economic traits. Thus, the associations between tree growth rates and functional traits are size dependent. Our results suggest ontogenetic shift of functional traits which could potential contribute to different growth response to climate change.

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Crown stratification by species in even-aged mixed stands of Douglas-fir – western hemlock

Canadian Journal of Forest Research ◽

10.1139/x79-001 ◽

1979 ◽

Vol 9 (1) ◽

pp. 1-9 ◽

Cited By ~ 45

Author(s):

Charles A. Wierman ◽

Chadwick Dearing Oliver

Keyword(s):

Growth Rates ◽

Species Differences ◽

Douglas Fir ◽

Growth Patterns ◽

Vertical Stratification ◽

Western Hemlock ◽

Diameter Growth ◽

Interaction Patterns ◽

Mixed Stands ◽

Study Management

The pattern of vertical stratification in mixed Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) and western hemlock (Tsugaheterophylla (Raf.) Sarg.) stands was documented by observing tree interaction patterns on temporary plots in stands between 35 and 80 years old. It was found that Douglas-fir predictably dominated the hemlock. Several possible causes of the stratification were studied. They were differences in ages between species, differences in mortality patterns, and differences in growth rates. Increment borings of trees on sample plots in the 35- to 80-year stands with the observed stratification revealed the overtopping Douglas-firs and suppressed hemlocks to be essentially of the same age. Searches for dead or dying Douglas-fir in groups of mixed stands of 35 to 80 years, 22 to 35 years, and less than 12 years revealed very little Douglas-fir mortality by suppression. Therefore, the possibility of death of intermediate and suppressed Douglas-firs was not an important factor leading to Douglas-firs being found primarily in the upper crown positions. Height and diameter growth patterns of closely growing codominant Douglas-firs, co-dominant hemlocks, and suppressed hemlocks were documented by stem analyses. Douglas-fir became significantly taller than the hemlocks after about 20 years and suppressed competing hemlocks. The possibility of stratification in mixed planted stands is less certain, since only young planted stands were available for study. Management of such mixed stands appears to improve the yield and quantity of wood and reduce or eliminate costly precommercial thinnings.

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Effect of Cyclic Irrigation on Growth of Magnolias Produced Using Five In-ground Systems

Journal of Environmental Horticulture ◽

10.24266/0738-2898-21.3.148 ◽

2003 ◽

Vol 21 (3) ◽

pp. 148-152

Author(s):

R. C. Beeson ◽

K. Keller

Keyword(s):

Growth Rates ◽

Shoot Growth ◽

Similar Rate ◽

Height Growth ◽

Irrigation Event ◽

The Other ◽

Diameter Growth ◽

Trunk Diameter ◽

Magnolia Grandiflora ◽

Ground Systems

Abstract Five in-ground systems were evaluated based on shoot growth and marketability for the production of 2.17 m (7 ft) tall and 5.08 cm (2 in) trunk diameter Magnolia grandiflora cv. ‘Symmes Select’. Systems evaluated were Root Control Bags, Geo-Cell bags, and #25 containers in pot-in-pot in Experiment 1, and Agro-liners in socket pots and directly in-ground in Experiment 2. Each system was either cyclically irrigated or given a single irrigation event daily. In Experiment 1, cyclic irrigation increased the rate of height growth and trunk diameter compared to a single irrigation. Trees in Root Control Bags and pot-in-pot grew at a similar rate and faster than those in Geo-Cell bags. Faster growth rates with cyclic irrigation resulted in earlier marketability compared to single irrigation daily, except for pot-in-pot. In Experiment 2, cyclic irrigation increased the rate of trunk diameter growth, and Agro-liners in pots had greater height and trunk diameter growth rates than those directly in ground. Trees grown in the in-ground pot systems, whether in Agro-liners or black polyethylene containers, grew similarly to trees in Root Control Bags. Trees grown in Geo-cells or Agro-liners in-ground had significantly slower growth than the other treatments.

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Trimeresurus malabaricus bites: Need of species-specific management for snakebites

Journal of Emergencies Trauma and Shock ◽

10.4103/jets.jets_3_20 ◽

2020 ◽

Vol 13 (2) ◽

pp. 167

Author(s):

SManu Ayyan ◽

M Harikrishnan ◽

KVimal Rohan

Keyword(s):

Trimeresurus Malabaricus ◽

Species Specific ◽

Specific Management

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Effects of seasonality, fertilization and species on the chlorophyll a fluorescence as related with photosynthesis and leguminous tree growth during Amazonian forest restoration

10.1101/2020.11.17.386342 ◽

2020 ◽

Author(s):

Roberto Kirmayr Jaquetti ◽

José Francisco de Carvalho Gonçalves ◽

Henrique Eduardo Mendonça Nascimento ◽

Karen Cristina Pires da Costa ◽

Jair Max Fortunato Maia ◽

...

Keyword(s):

Electron Transport ◽

Performance Index ◽

Forest Restoration ◽

Cost Effective ◽

Interspecific Variation ◽

High Water ◽

Diameter Growth ◽

Cost Effective Technique ◽

Species Specific ◽

Degraded Ecosystems

AbstractThe ability of species to adjust their light energy uptake is determined during plant establishment and development. Changes in resource availability may impact energy fluxes and photosynthesis. General and specific variations in chlorophyll a fluorescence under high vs. low water and nutrient conditions have been studied. N2-fixing leguminous trees, which are commonly used in tropical forest restoration, seem to be very well adapted to degraded ecosystems. To understand the effects of biological nitrogen fixation on Chl a fluorescence variables, three of the six Fabaceae species selected for this study were N2-fixing species. Additionally, the correlation among Chl a fluorescence and growth, photosynthesis and nutrient levels was evaluated. A 24-month forest restoration experiment was established, and data on dark-adapted Chl a fluorescence, photosynthesis, diameter growth and foliar nutrients were collected. Multivariate analysis was performed to detect the effects of seasonality and fertilization. Under high water- and nutrient-availability conditions, plants exhibited enhanced performance index values that were correlated with electron transport fluxes. Under drought and nutrient-poor conditions, most species exhibited increased energy dissipation as a method of photoprotection. Great interspecific variation was found; therefore, species-specific responses to the test conditions should be considered in future studies. N2-fixing species showed increased performance index and maximum fluorescence values, indicating their ability to colonize high-light environments. Negative correlations were found between photosynthesis and trapped fluxes and between diameter growth and initial fluorescence. Electron transport fluxes were positively correlated with growth. Given the different responses identified among species, Chl a fluorescence is considered a cost-effective technique to screen for seasonality, nutrient and N2-fixing species effects and should be considered for use during forest restoration. Finally, including N2-fixing species and multiple fertilization treatments in related studies may greatly facilitate the restoration of biogeochemical cycles in the tropics.

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Drought responses and their effects on radial stem growth of two co-occurring conifer species in the Mediterranean mountain range

Annals of Forest Science ◽

10.1007/s13595-020-01007-2 ◽

2020 ◽

Vol 77 (4) ◽

Author(s):

Aylin Güney ◽

Roman Zweifel ◽

Semra Türkan ◽

Reiner Zimmermann ◽

Magnus Wachendorf ◽

...

Keyword(s):

Water Deficit ◽

Growth Rates ◽

Water Shortage ◽

Stem Growth ◽

Growth Strategy ◽

Mountain Range ◽

Summer Drought ◽

Cedrus Libani ◽

Juniperus Excelsa ◽

Species Specific

Abstract Key message Patterns of stem radial variations showed thatCedrus libaniA. Rich. was less limited by summer drought than co-occurringJuniperus excelsaM. Bieb.Cedrus libanirecovered faster from tree water deficit and showed significantly higher radial growth rates and annual stem increments thanJ. excelsa. However, the ability ofJ. excelsato grow more hours per year may indicate a potential benefit in more extreme conditions. Context Knowledge about species-specific drought responses is needed to manage productive forests in drought prone areas. Under water shortage, trees commonly show stem shrinkage, which is assumed to inhibit growth. Aims We investigated whether the two co-existing conifers Juniperus excelsa M. Bieb. and Cedrus libani A. Rich. (growing at the Taurus Mountains, SW-Turkey) show differences in water relations and stem growth in order to evaluate their respective drought tolerance. Methods Stem radius changes were hourly monitored over 2 years using high-resolution point dendrometers. Radial stem growth, tree water deficit-induced stem shrinkage, and maximum daily shrinkage were extracted from stem radius change measurements, investigated for their patterns, and related to environmental conditions. Results Cedrus libani recovered from tree water deficit under higher temperature and vapor pressure deficit than J. excelsa. The number of hours during which stem growth occurred was higher for J. excelsa; however, growth rates and annual increments were significantly lower than in C. libani. Both species showed highest maximum daily shrinkage during the driest months indicating the ability to maintain gas exchange all year round. Conclusion Juniperus excelsa showed a more conservative growth strategy while C. libani was less limited by summer drought and showed more annual stem increment under the conditions investigated.

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Status of the Major Commercial Fish Stocks and Proposed Species-specific Management Plans for Lake Victoria

African Journal of Tropical Hydrobiology and Fisheries ◽

10.4314/ajthf.v12i1.57366 ◽

2010 ◽

Vol 12 (1) ◽

Cited By ~ 4

Author(s):

R Kayanda ◽

A Taabu ◽

R Tumwebaze ◽

L Muhoozi ◽

T Jembe ◽

...

Keyword(s):

Lake Victoria ◽

Commercial Fish ◽

Fish Stocks ◽

Management Plans ◽

Species Specific ◽

Specific Management

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Perturbing phytoplankton: response and isotopic fractionation with changing carbonate chemistry in two coccolithophore species

Climate of the Past ◽

10.5194/cp-6-771-2010 ◽

2010 ◽

Vol 6 (6) ◽

pp. 771-785 ◽

Cited By ~ 77

Author(s):

R. E. M. Rickaby ◽

J. Henderiks ◽

J. N. Young

Keyword(s):

Organic Matter ◽

Growth Rates ◽

Isotopic Fractionation ◽

Carbonate Chemistry ◽

Species Response ◽

Carbon Isotopic ◽

Ph Buffer ◽

Coccolithus Pelagicus ◽

Species Specific ◽

Gephyrocapsa Oceanica

Abstract. All species of coccolithophore appear to respond to perturbations of carbonate chemistry in a different way. Here, we show that the degree of malformation, growth rate and stable isotopic composition of organic matter and carbonate produced by two contrasting species of coccolithophore (Gephyrocapsa oceanica and Coccolithus pelagicus ssp. braarudii) are indicative of differences between their photosynthetic and calcification response to changing DIC levels (ranging from ~1100 to ~7800 μmol kg−1) at constant pH (8.13 ± 0.02). Gephyrocapsa oceanica thrived under all conditions of DIC, showing evidence of increased growth rates at higher DIC, but C. braarudii was detrimentally affected at high DIC showing signs of malformation, and decreased growth rates. The carbon isotopic fractionation into organic matter and the coccoliths suggests that C. braarudii utilises a common internal pool of carbon for calcification and photosynthesis but G. oceanica relies on independent supplies for each process. All coccolithophores appear to utilize bicarbonate as their ultimate source of carbon for calcification resulting in the release of a proton. But, we suggest that this proton can be harnessed to enhance the supply of CO2(aq) for photosynthesis either from a large internal HCO3- pool which acts as a pH buffer (C. braarudii), or pumped externally to aid the diffusive supply of CO2 across the membrane from the abundant HCO3- (G. oceanica), likely mediated by an internal and external carbonic anhydrase respectively. Our simplified hypothetical spectrum of physiologies may provide a context to understand different species response to changing pH and DIC, the species-specific εp and calcite "vital effects", as well as accounting for geological trends in coccolithophore cell size.

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