Tree Growth - Science topic

Hi Thomas Ibanez ,

There are some good suggestions in the thread here, particularly the points raised by Andrew Gray

I guess I came to terms / settled back on the classical empiricist's adage: "The data are what the data are [what the data are]..." My initial motivation for asking this question was more of a statistical one -- trying to get a model with gamma likelihood (which will not allow zero or negative growth) to fit.

In this case, I ended up using a truncated normal likelihood, which is a lot like a gamma in terms of shape but gives a little bit more flexibility regarding the linkage of the likelihood function to the process model. One can truncate the distribution at various growth magnitudes (negative numbers, zero, or around zero/ some small positive number).

Work by Nadja Ruger et al -- PlosOne 2012 10.1371/journal.pone.0025330 -- and subsequent work from her lab/ this line of research, discuss one potentially promising approach that can be employed. (see Methods section on Growth data), they do some data cleaning but then estimate measurement error and include that in the model's parameterization (a Bayesian model allows for this).

It comes down to the questions and how much any assumptions made with the data will affect inference. If the objective is to model growth, then including trees that don't grow potentially confounds any signal; however, we know not all trees grow. You can always run the model on different subsets of the data to see the impact of non-growing/ shrinking trees, which is a good exercise/ sanity check. I hope that's helpful; I wish I had a more straightforward/ better answer. I am happy to talk more about this if you would like.

Cheers, Aa

Altitudinal gradients, which represent changes in environmental conditions with increasing elevation, can have significant impacts on the biomass and carbon stock of coniferous forests.

Here's how these gradients can influence these aspects:

In summary, altitudinal gradients can have complex and interacting effects on the biomass and carbon stock of coniferous forests. The specific impacts will depend on a combination of factors including temperature, precipitation, nutrient availability, competition, disturbances, and species adaptation. Understanding these dynamics is important for predicting how coniferous forests might respond to changes in climate and land use along altitudinal gradients.

Any deviation from its normal value said that climate change. It included all parameters like rains, temp., humidity, BSH, wind etc that have great effect on growth and development of plant. Excess or deficit of thses factors may damage plant. Eventhough, plant has mechanism to adopt under adverse condition by producing HSPs, chaperons, dehydrin protein, LEA protein, these protect plant from abonormal anomalies.

That is possible , but need simultaneous data for such correlation studies..

Or alternatively , have 12 observations on ring growth data then correlate with monthly temperature and precipitation data to see , which month temperature and precipitation has minimum or maximum influence on ring growth ...lets try this way...hope it settles your querry..

If I do not know the annual rings, how to calculate

Dear Natalia

Tree growth can be seen from different perspectives, for example, height growth, diameter growth, volume growth and etc. For diameter growth, tree rings are measured and each ring represents the growth in a year. You can watch this video:

https://www.youtube.com/watch?v=ERu1WtO3J0k

regards,

Hormoz

Some canadian researchers are using some drone technology for measuring angles of branches etc but that technology is very expensive.Personally i dont know any manual method.

Dear Birhanu Kagnew, I agree with your statement, but I would advise against

inoculating with mycorrhizal products, derived from other environments. That can have consequences like mutations, that are not always desirable.

If instead, we support the local ones, even if in minimal amounts, the results are much better. Altering the micro equilibrium with "foreign" organisms, is not wise.

Thank you James and Hubertus.

There are studies back around 2001 by Dirk Dujesiefken from Hamburg, Germany, with a few pubs in German (I have the citations). He compared a variety of options and in very rare cases it was recommended to plug the hole. But rule of thumb is do NOT pug holes at all. Plugging is in most cases worse than anything else. So dont plug holes, also dont use any desinfection treatment, and by no means any "balsam".

Hi Fabrizio D'Aprile,

Read the following articles, I hope it helps.

cheers.

Dear have a look at this attached pdf guideline for quantification of actual Carbon in forest ecosystems.

The early phase of the interaction between tree roots and ectomycorrhizal fungi, prior to symbiosis establishment, is accompanied by a stimulation of lateral root (LR) development. We aimed to identify gene networks that regulate LR development during the early signal exchanges between poplar (Populus tremula 3 Populus alba) and the ectomycorrhizal fungus Laccaria bicolor with a focus on auxin transport and signaling pathways. Our data demonstrated that increased LR development in poplar and Arabidopsis (Arabidopsis thaliana) interacting with L. bicolor is not dependent on the ability of the plant to form ectomycorrhizae. LR stimulation paralleled an increase in auxin accumulation at root apices. Blocking plant polar auxin transport with 1-naphthylphthalamic acid inhibited LR development and auxin accumulation. An oligoarray-based transcript profile of poplar roots exposed to molecules released by L. bicolor revealed the differential expression of 2,945 genes, including several components of polar auxin transport (PtaPIN and PtaAUX genes), auxin conjugation (PtaGH3 genes), and auxin signaling (PtaIAA genes). Transcripts of PtaPIN9, the homolog of Arabidopsis AtPIN2, and several PtaIAAs accumulated specifically during the early interaction phase. Expression of these rapidly induced genes was repressed by 1-naphthylphthalamic acid. Accordingly, LR stimulation upon contact with L. bicolor in Arabidopsis transgenic plants defective in homologs of these genes was decreased or absent. Furthermore, in Arabidopsis pin2, the root apical auxin increase during contact with the fungus was modified. We propose a model in which fungus-induced auxin accumulation at the root apex stimulates LR formation through a mechanism involving PtaPIN9-dependent auxin redistribution together with PtaIAA-based auxin signaling ( Plant Physiology
, December 2009, Vol. 151, pp. 1991–2005 )..Some interesting PDFs enclosed

You can try the approaches presented in the articles below. The idea is to modify the parameters of a growth function (in these cases Chapman and Richards) to be sensitive to environmental variations.

Dear sir, have a look at these important attachment.

Average growth rates for your forest trees/stands are a function of soils and site (Site Index); stocking; past forest management (thinning, crop tree release, cull tree removal, etc.); species, vigor, and crown condition; and of course genetic potential. Therefore, accurate data must be collected from deceduous forest in order to obtain appropriate growth rate data.

CHECK THE FILE GIVEN BELOW

Some reference values per ha that apply to temperate and possibly tropical forests with a distinction between young and mature.

good luck

bark colour is usually different. Also, look at internode length, it is usually longer during spring time.

Crawking Woodfrog

Another strategy is to consider your pretrial measurements as a covariate. With growth, growth will depend on initial size, and may be better expressed on a logarithmic scale (what percentage increase) rather than on a unit scale. 

I'm thinking that if one tree is 100cm and another is 200 cm, what is the expected growth? 10cm or 10%? 

Losing the baseline information by simply subtracting is removing an potentially important variable from the data generation process.

Thanks

Thank you so much! This is going to be extremely useful!

Hi,

I also recommend CooRecorder and basically any flatbed scanner (higher resolution is better). It is worth mentioning that actually you are buying packed of softwares from Cybis. It is called Cdendro and includes two programs: CooRecorder, which is dedicated to measure ring widths and also other parameters and CDendro which is tool to test the quality of measurements, crossdate and build chronology.  It is easier to work using this couple of programs because the file formats is identical. I recommend using Cofecha, which is great tool or/and dplR only as a next step.

Good luck and don't hesitate to ask about details if necessary!

Spiral trenches can be simplified by radial trenches taken under crown at 1, 2 and 3 m from trunk if soil horizon is homogeneous. Then you can evaluate root density by separating excavated roots from soil and obtaining root ditribution profile with depth and radial distance. Steps are graded every 20cm.

See: The Chapman-Richards Generalization of Von Bertalanffy's Growth Model for Basal Area Growth and Yield in Even - Aged Stands, Forest Science, Volume 19, Number 1, 1 March 1973, pp. 2-22(21).

This paper may help you to predict the basal area development of stands of different initial stocking and subsequent thinning regimes. 

That would be a good question. I hope there would be a sophisticated investigation in this regard. I have not found any good investigation up to know either. I would be glad to know more about that.

Using Murashige and Skoog (MS) medium supplemented with 6-benzyl amino purine (BAP) 0.5 mg/l along with gibberelic acid (GA3) 2.5 mg/l produced multiple shoots. Repeated and periodic subculturing yielded better growth and further shoot multiplication on the same medium of Melia dubia. Thus, using tissue culture technologies such as the micro propagated plantlets are successfully acclimatized with 90% survival rate of Melia dubia.

Dear Ms. Motyka,

Sounds interesting and made me think loudly of other climbers/vines as well. What about certain (by assumption) native Clematis or Laburnum species, Hedera helix, Lonicera caprifolium even Ephedra campylopoda [E. foeminea] (if native), though the natural site conditions are very much different. Just a thought, of course... All become quickly spread and are fast-growing species.

And, what about (by assumption non-)native Parthenocissus spp. or another ornamental Wisteria sp.? If possible, these species will give the landscape various color and dynamic.

Junipers are not vines, but some prostrate shrubs of the genus Juniperus are known for their widespread ecology and competitiveness, such as J. sabina...

It is a good start point!

Best regards.

Thanks Klemens. I will see the project details and text send by you.

Please follow the below links and PDF attachments.

Good luck

Simple, and often used, tree species density measures are trees per unit area and basal area per unit area. These can be separated by tree species. Field plots are best for determining these. Remote sensing might be used, but species below the main canopy might be missed.

The problem here is that you are referring to an agroforest setting, if the papers you are considering were not developed with agroforest data the relationship between height and diameter may differ. For example, dense forest will generally have more height by diameter than sparse agroforest. Check that out first. If this may be a problem, utilize the two variable models. If it will not be a problem (tree species height-diameter not impacted by density or diameter only model included agroforest data) then you should use the diameter only model.

Diarmuid,

Have you reached out to KaDonna Randolph from the US Forest Service? She is the current national lead for the crown indicator(s) described by Bechtold et al. and might have some insight regarding your proposed field implementation.

 krandolph@fs.fed.us

I have a strong feeling that lichens do not like fungicides. So quantify the number of lichens on a unit surface trunk in function of the application of your fungicide, and the answer will soon be yes or no for lichens as indicators for fungicide application. You will have to do this experiment as well in function of air pollution levels, because lichens are very sensitive to air pollution as well.

Cheers,

Frank

Dear Rajesh, I think you are talking about the seedlings under forest canopy. Irrespective of place where they are growing, PAR should be measured above the canopy of the plants of your assessment and thus above the height of the seedlings. Naturally the PAR will be different below forest canopy and open areas.

Dear Astrid,

I have mostly measured ring width visually, with tools such as Lintab. In general, I would say that software measuring, based on scanned images, can be particularly profitable when you have many cores which are fairly easy to be measured, e.g., conifers in cold or temperate environment. Then, these tools can be faster than humans. But if you have few cores (let’s say, less than one hundred) maybe the time you save is less than what you spend in setting the software. Moreover, if rings are not easy to be identified in your cores, and there are problems such as partial rings, small rings, doubts on what are the ring borders, I suggest you to measure them visually.

As suggested earlier, cropwat will help you to get the data for the desired crop and for the desired location, if you have the meteorological data. For ready made data, you can refer the book by INCID on Drip Irrigation in India, in which the quantity of water for different crops in Maharashtra is also there

There are a number of approaches. One approach is to use and independent dataset and compare the observed and the predicted values (using the old growth model and the new re-parameterized model) and compare bias (for example, Mean squared error, Mean bias, Absolute mean bias, and Mean absolute percent error). Analysis of the residuals will show if there is any improvement over the old growth model. Fundamentally, model testing and validation of a predictive model involves assessing the effectiveness of the fitted model against an independent set of data followed by a robust residual analysis, because the main key to the suitability of a predictive model is contained in the residuals.

However, if you do not have access to an independent dataset, select 10 or 20 percent of your dataset to set aside for model validation. Then, fit both models (old growth model and the new re-parameterized model) with the remaining 80 or 90 percent of your dataset. Finally, using the validation datasets compare the observed and the predicted values and compare bias.

Different interaction processes between atmospheric pollution and urban trees exist, exerting both positive and negative air quality impacts;

Smart implementation (and not just implementation) of urban green in cities is, therefore, vital to obtain positive air quality outcomes!

Moreover, we can't forget that, apart from air quality, urban green offers numerous indispensable ecosystem services!

Please check the following link for your desired study

Use of Calcium/Aluminum Ratios as Indicators of Stress in Forest Ecosystems

Christopher S. Cronan * and David F. Grigal

+ Author Affiliations

Abstract

The calcium/aluminum (Ca/Al) molar ratio of the soil solution provides a valuable measurement endpoint or ecological indicator for identification of approximate thresholds beyond which the risk of forest damage from Al stress and nutrient imbalances increases. The Ca/Al ratio can also be used as an indicator to assess forest ecosystem changes over time in response to acidic deposition, forest harvesting, or other processes contributing to acid soil infertility. Based on a critical review of literature on Al stress, we estimate that there is a 50:50 risk of adverse impacts on tree growth or nutrition when the soil solution Ca/Al ratio is as low as 1.0, a 75% risk when the soil solution ratio is as low as 0.5, and nearly a 100% risk when the soil solution Ca/Al molar ratio is as low as 0.2. The Ca/Al ratio of the soil solution can be corroborated with other complementary indices. Our analysis found that threshold conditions for potential forest impacts from Al stress are indicated by four successive measurement endpoints: (i) soil base saturation less than 15% of effective CEC; (ii) soil solution Ca/Al molar ratio ≤1.0 (for 50% risk); (iii) fine root tissue Ca/Al molar ratio ≤0.2 (for 50% risk); and (iv) a foliar tissue Ca/Al molar ratio ≤12.5 (for 50% risk). With appropriate precautions and caveats, these sequential indices based on the Ca/Al ratio provide a means of distinguishing site conditions where Al stress is likely to affect tree growth adversely.

Another one...

addition agricultural residues to tree crop will conserve the soil moisture. cool or moisture surrounding attract the invertebrates thereby increase soil organic carbon.

negative it will habitat for pest and pathogens.

https://www.researchgate.net/publication/257197917_The_manipulation_of_organic_residues_affects_tree_growth_and_heterotrophic_CO2_efflux_in_a_tropical_Eucalyptus_plantation

http://www.sfrc.ufl.edu/CFEOR/LogIn/log%20in%20docs/recent%20research/2015_05_08%20Achat%20et%20al.pdf

Hi Tina,

I think that maybe you should check a scientific paper from Institute of Dendrology PAS in Poland.  Two LABs in this institution works how  heavy metal influences on trees species. Research were done in different area than yours, but maybe this papers would be useful for discussion.

Hope it helps you!

Hi Iulian,

Here are some ideas for increasing poplar biomass, based on my observations (we have not yet harvested trees):

1) In general, I think a N/S stand orientation takes more advantage of available sun, but some people plant E/W, or parallel to prevailing wind, or on the contour of the site (it depends on the site, really).

2) if your past research indicates that your poplar variety has good survival (>95%), then you can probably expect good survival at various spacings.

3) Need to think about how the poplars will be maintained (trimmed or not trimmed during growth), and how they will be harvested (chainsaw or small/large mechanical harvester). We trim our trees by hand up to head height for most of our trees (to get a single large stem), but we do have a close-spaced trial which is not trimmed. Survival and health was lower in close-spaced trees. It is difficult to walk through/access the trees when they are 2m x 2m and not trimmed.

4) Do the trees need any type of fertilizer (such as urea nitrogen, or iron)? This will depend on the soil type and soil pH. This is best delivered through a drip irrigation system, which is not expensive (at least for the water driplines).

5) Maybe consider an understory grass or legume, to enhance soil fertility.

6) Also consider WHO will be harvesting the trees. If a contractor logging company, then it will be good to check with them, to see what size/form they need in order for the material to fit on their trucks and for them to make a profit.

7) In my view, I think it's best to plant small cuttings that have a few buds.

8) All in all, I think you will have success at whichever spacing you choose, if you have a site-appropriate variety. 

See p. 143 in our Annual Report, for info on planting techniques and data on biomass yield of trees planted at 10 ft or 12 feet apart (some were planted in 2002, 2005 and 2007). I think we also have older data on close-planted trees planted in 2003. Here is the link on our reports:

These are some ideas. Hope this helps. Will be glad to hear more about your project. 

Best,

Sam

  To calculate stem volume knowing basal diameter and length, you have to make an assumption about taper. In trees, the clear trunk excluding the root flare often tapers as a parabaloid (to calculate which you'd need either top diameter as well as basal diameter, or diameter at the mid-point), while the top part of the tree, within the crown, often tapers as a cone..

  If you have only one diameter measurement you also have to assume that the cross-section of your seedling stems is circular, which may not be strictly correct, and you may also be most interested in stem volume in relation to some other variable (leaf area, growth rate etc).

  It might be best to accept that you can calculate an index of stem volume, rather than actual stem volume. In that case the index would probably be equally informative whatever you assume about taper and cross-sectional shape.

Please follow the following link and reference which probably may help you.

Pfeffer, M. (2005). Regression-based Age Estimates of Yellow Pine Saplings, Jefferson National Forest, Virginia. A Senior Honours Thesis. The University of Tennessee-Knoxville

Please see the paper of non-destructive techniques measuring stiffness on pinus radiata seedlings. This might be useful for your research. 

I agree with Stella Bogino you can determine the age of Amygdalus scoparia trees by counting the number of tree growth rings.

As a pasture tree, open grown, Guanacaste of this size may average 1 cm/yr diameter growth, giving an age estimate of about 200-300 years.

I have tried eCognition.  It is a useful tool as suggested by Mathieu.  Here is the reference to one paper:

Karlson, M., Reese, H., & Ostwald, M. (2014). Tree Crown Mapping in Managed Woodlands (Parklands) of Semi-Arid West Africa Using WorldView-2 Imagery and Geographic Object Based Image Analysis. Sensors, 14(12), 22643-22669.

Also, you may want to read this:

Zagalikis, G., Cameron, A. D., & Miller, D. R. (2005). The application of digital photogrammetry and image analysis techniques to derive tree and stand characteristics. Canadian journal of forest research, 35(5), 1224-1237.

Cheers!

You should measure a related variable like shoot basal radii and use allometric scaling on a robust sample. The principles are drawn in Brian Enquist https://www.researchgate.net/profile/Brian_Enquist/publication/11051612_Universal_Scaling_in_Tree_and_Vascular_Plant_Allometry_Toward_a_General_Quantitative_Theory_Linking_Plant_Form_and_Function_from_Cells_to_Ecosystems/links/09e4150c6bb5e827d2000000.pdf and subsequent papers. On big trees trink radius is the main variator.

Here is the 'classic' reference for a pith locator: Applequist, M.B. (1958). A simple pith locator for use with off-centre increment cores. Journal of Forestry 56: 141.  If you want to get quantitative, another one is Liu, CJ. (1986). Rectifying radii on off-center increment cores. Forest Science 32: 1058-1061.

cheers,

Elaine

Good question: you are correct that there are clearer are more widely applied guidelines on tree health metrics for larger trees (for example in an urban forestry context).

The most common health metrics used for saplings are essentially based on growth as an integrated measure of tree health, with non-destructive measures commonly based on root collar diameter and height (and sometimes leaf area).  Annual extension growth quantified by terminal leader length is also useful, particularly in temperate or boreal trees with annual internode production.  One can also utilize either sequential harvests or allometric estimates to derive "growth analysis" metrics (i.e., relative growth rate, leaf area ratio, unit leaf rate (= net assimilation rate), leaf mass fraction, etc.) that have been commonly used in the agronomic literature (Hunt et al. 2002 give a helpful overview).

Depending on the context (and available instrumentation) additional useful metrics would include leaf survivorship, leader loss, leaf chlorophyll content, chlorophyll fluorescence parameters (especially Fv/Fm), and photosynthetic gas-exchange parameters.  There is of course a large plant stress physiology literature and many other techniques that could in theory be used (membrane leakage, antioxidant content, analysis of xanthophylll cycle pigments come to mind), but most likely these measurements are mainly useful if you are seeking to understand physiological mechanisms involved.

I've attached a study from my lab as an example that includes parallel work on canopy trees and saplings.

Reference:

Hunt, R., Causton, D. R., Shipley, B., & Askew, A. P. (2002). A modern tool for classical plant growth analysis. Annals of Botany, 90(4), 485-488.

Trees are the largest plants in Terraria, appearing mostly at the surface and often in clusters with similar height. Trees can be chopped down with an axe, with the use of explosives, or by pouring lava on the base. Destroying or chopping a tree will yield many units of wood, an essential crafting material, and give a chance of dropping one or more acorns that can be planted to grow more trees. Larger trees will yield more of these two materials when removed, since the amount of wood and acorns obtained from a tree depends on its size: one unit of wood will drop for each block of tree (including branches), and one acorn may drop for each leaf patch, excluding the top patch of leaves. It is possible to cut off parts of the tree, but cutting at the lowermost center tile will destroy the entire tree. If parts of the tree are left, they will not regrow. Tiles beneath trees cannot be destroyed while the tree stands.

Dear,

I think the paper attached can help you.

Regards

Dear Yunan,

Before contaminating your soil with high doses of an unknown auxin (with a low purity) and defoliating your beloved trees, I recommend learning something about the nature of auxin, and in particular about auxin action. For example, Wikipedia would explain you that auxins are plant hormones that trigger plant responses at very low concentrations. (endogenous: IAA = indole-3-acetic acid). In addition, synthetical auxin analogues (IBA = indole-3butyric acid; NAA = naphthalene acetic acid) are sometimes used in commercial horticulture and in plant tissue culture for root induction in cuttings of heavy-to-root plants but never for promotion of root growth!

Other synthetical auxins are known to be misused by air spraying leading to defoliation of thousands of hectares of jungle wood trees in South Vietnam by the U.S. military during the Vietnam war ("Agent Orange"; "Agent Blue").

Since the information about military use of Agent Orange and Agent Blue are accessible  for a couple of years, you can "google" the terrible "long term toxic side effects" of these chemicals (and their impurities, respectively) on the health of the Vietnames people which have to live on the contaminated soils.

My personal summary as a plant phsiologist who wrote his dissertation on problems of auxin action and who worked for several years in the field of plant tissue culture:

To prevent potential harmful health effects, bring back your undefined auxin to its deliverer and ask an experienced gardener for the health problems of your trees.

Greetings, Bernd

First of all, thank you for spending time to answer. The issue is more complicate than it may seen at first glance. Fast dying out as a consequence of extreme climate conditions is difficult to analyse because it can be an exceptional event to which add various different biological, site, soil, and possibly management factors. I would call it a 'catastrophic' or 'shock' event. However, events like this have always occurred and are 'part' of climate variability.   What I mean instead is, the thresholds for tree growth above and below which growth starts to increase or reduce as a main trend. For example - and roughly - two weeks of average daily temperature above 9 degrees without any occurrence of daily temperature  below 0 degrees  are considered by some authors an approximate threshold for the start of silver fir growth in spring in Italy. 

Hello Abdou

We use the technique developed by Professor Ronald de Fossard which is a series of experimental media with different levels, originally he had 81 experimental media, he then modified this in 2003 to 23.  His CD's are available if you google him online.

We stopped wasting time and media once a known formula did not work.  It was worth the effort with the stock solutions in the end.  Sometimes we focus on the hormones and not the media composistion

Professor de Fossard developed these so that there was a scientific method in developing media protocols and we find this resource invaluable

I hope this is of some assistance and would encourage you to also try the metapolin as a cytokinin too.

Please look into publications by Dr. Kalidas Shetty, Professor, North Dakota State University. You can access his bio through google.

Best Regards

GP.

Sir

I am trying estimation of forest canopy closure from simple photographs. However, I am still not sure on the methodology to separate canopy and non-canopy from photographs. I can do it in some image processing software. And I don't know of any instrument to estimate canopy volume. Of course, I have not googled this yet!

But in your case, I think Google-Earth can be a useful tool. Nowadays, GE can be downloaded on smartphones. There you can measure diameter of individual trees. Once a relationship is fixed between canopy diameter and canopy volume, the further relationship can be worked out between canopy diameter and quantity of agro-chemicals. This way, a farmer will just need to measure canopy diameter on GE.

Working out the relationships would be very easy and I would like to work on it with you.

Best

Dear Gerardo,

we studied height growth of Iriartea, Euterpe precatoria and Cryosophila warscewiczii in a permanent plot in Costa Rica:

Homeier, J., Breckle, S. W., Dalitz, H., Leyers, C., & Ortiz, R. (2002). DEMOGRAPHY, SPATIAL DISTRIBUTION, AND GROWTH OFTHREE ARBORESCENT PALM SPECIES IN ATROPICAL PREMONTANE RAIN FOREST IN COSTA RICA. Ecotropica 8:239-247.

The study is ongoing but most current data are still not published.

Best regards

Jürgen

It all depends on what kind of trees you want to generate.

If you mean the trees as the vegetation, then there is a SpeedTree app for such purposes.

Hello Ardalan,

Yes it happens. Age groups of a particular species have been made by many researchers using the spectral responses of vegetation from both ground and airborne sensors. This becomes possible only due to differences in spectral responses. LAI plays an important role in this phenomenon. La Porta N publications are worth to study. 

measuRing.- A package in R for the identification of ring borders and  measurement of tree-ring widths on scanned image sections from dendrochronological samples. This tool, integrates measurement of tree-ring widths with powerful statistical analyses within the R environment.  

Hey Geoff, been a while.  Good to see your still working on the cambium.  In northern ontario as a few have mentioned elsewhere we see site as influencing height but also stand density, the more open the shorter, so essentially competition restricting multiplicative growth in favour of additive growth. Aside from genetics and site conditions competition seems to be a major driver.  If you look at some of the work Tony Zhang from FPInnovations did years ago it clearly shows this trend.

Thanks Alot friends for your articles that send to me, best for you. i will check them

It really depends on your ecosystem and species involved, as S. Hari indicates.  In many places the pulse of recruitment can last decades, with gradual infilling; in others, if recruitment doesn't happen right away, grasses, sedges, and other species can out compete seedlings for water and succession much delayed.  There are many things that influence this rate- climate in the following years, distance from the intact edge, whether it's a good seed crop year for the survivors, herbivory/seed predation, etc.  Also the intensity of the fire may matter, if it alters the biogeochemistry or physical properties of the soil in some way (at least some abnormal way).

So overall, it really depends on the system and species.  In most places, though, you've got to give it a few years for seed from the outside.

I would recommend looking for post-fire studies in your ecosystem and then looking into the methods sections to see how long post-fire the study was done.  But again, other things will matter which vary, like climate, distance from edge, etc...

for Iulian Danila: You can try to apply this approach for poplar, too. It is necessary to think over the method of estimating the times of appearance and dying off for all orders of tree branches.I think it is not very difficult, at least with an accuracy of not less than year. You also need to have a description of growth features of the poplar, its morphology and physiology, for example, like that described in the article GalitskiVV,2013 - BBRV412.pdf (see above). Actually, I think it would be useful to repeat such a study first on some coniferous trees - spruce, pine, Araucaria.

Temperature will influence seedlings in different ways in different phases of their development.

At the beginning increased temperatures in temperate climate may cause lack of germination at all. Many seeds are dormant and one of the ways to break dormance is exposure to low temperatures. Very important is also stability of temperature (or its fluctuation) - see Baskin & Baskin Seeds. Ecology, Biogeography, and Evolution of Dormancy and Germination.

In next phases temperature will influence seedling physiology and here response depends on species traits - there are no generalizations I'm afraid (and I can't provide any literature source here)

Dear Bita,

have you seen the following references:

- Mean root depth estimation at landslide slopes

Original Research Article

Ecological Engineering, Volume 69, August 2014, Pages 118-125

S. Tron, A. Dani, F. Laio, F. Preti, L. Ridolfi

- The lateral spread of tree root systems in boreal forests: Estimates based on 15N uptake and distribution of sporocarps of ectomycorrhizal fungi

Original Research Article

Forest Ecology and Management, Volume 255, Issue 1, 20 February 2008, Pages 75-81

S.G. Göttlicher, A.F.S. Taylor, H. Grip, N.R. Betson, E. Valinger, M.N. Högberg, P. Högberg

- Measuring tilt of tree structural root zones under static and wind loading

Original Research Article

Agricultural and Forest Meteorology, Volume 168, 15 January 2013, Pages 160-167

Ken James, Craig Hallam, Chris Spencer

Hi Anya!

As far as I am concerned, this subject, tree health and it's defence against pest or other environmental stress, directly related to environmental or ecological factors including both abiotic and biotic factors affecting tree, forest and also whole plant community in terms of health and resistivity to any natural diseases.

May be there is indirectly a relation between tree growth and its defence but growing fast or not in trees  directly related to physiological and anatomical features under the same ecological condition.

So clearly, main answer is: Under the same ecological condition, we can not only say that fast growing trees healthier than the others. Its depend on ecological conditions.

SCENARIO 1: At general, Poplar is fast growing tree and it comsumes and needs more water than Oak species. So, If they grow in dry and semi dry condition, Poplar probably will have less resistivity than Oak. And this condition will be affect Poplar' physiological properties and finally it will be less resistivity to pest and the other env. stress. than oak. We can make an inference that.

SCENARIO 2: But, in humid contidion, we can not say that Poplar will be healtier than Oak. Can we?

Its one of the my little opinion:)

Good luck with your study.

Yes, possibly, and only for some species and only for a certain period of time. For instance, if you have independent data on the plastichron interval (i.e the period between the initiation of new leaves) for the site(s) you are working in, then it may be possible to count leaf scars on the seedlings of species of Rhizophora (and perhaps other genera in the Rhizophoraecea) to get a reasonable idea of age. This will only work up until the seedlings start to produce branches.

An excellent comparison of methods on "correlation/inferring from measured radial stem growth between/on height growth" is given in: Kariuki, m. (2002): Height estimation in complete stem analysis using annual radial growth measurements. Forestry (UK) 75: 63-74. It includes references to Carmeans, Lenharts, Newberry and Fabbio et al. methods. Have fun reading!

No. There is a species of Euphorbia on Mt Elgon (Uganda/Kenya) which grows to 30 m (E. obovalifolia)

We have an ongoing project (a year now) researching the economic potential of plantation floor biomass as products to increase soil productivity in the Andes. These plantations are of Pinus patula... If you are interested. I will really like to know about your experience...

@ If the species in question is present only at two localities. The tissue culture technology can be used to make large number of plants. These can be planted where ever possible to conserve this species.

Regards

Any plant that reproduces from clones, like the sump-sprouting Coast Redwoods in California or the clone ring-forming Creosote bushes in the Mojave desert, the clone forming Quaking aspen in Utah that is both one of the oldest individual organisms but also the largest, covering over 100 acres, and the grasses that only reproduce by underground runner roots instead of seeds, like sweetgrass (Hierochloe) are all essentially immortal, until climate change or geologic changes in the environment do not allow the individual plants to continue to live on that spot. 

In the Canary Islands, in regions with a low annual rainfall (below 250 mm), two of the very few indigenous trees that can grow in such environments are Tamarix canariensis and T. africana. In some cases, where there is some humidity, you can find also the endemic palm Phoenix canariensis. Tamarix species seem to grow quickly in some areas, and are very good for forestry purpose in semi-desert or even desert environments.

Hello!  Perhaps one or more of the following research articles (or references therein) might be of some interest to you:

Soil Organic C and Nutrient Contents under Trees with Different Functional Characteristics in Seasonally Dry Tropical Silvopastures* (CASALS et al., 2014)

(*) = A PDF copy of this research article is available on “Google”, posted by one of the co-authors, Graciela M. RUSCH, under the aforementioned title.

 

The Influence of Strata on the Nutrient Recycling within a Tropical Certified Organic Coffee Production System (MAMANI-PATI et al., 2012)

Spatial Variability of Nutrient Stocks in the Humus and Soils of a Forest Massif (Fougères, France)

[LEGOUT et al., 2008]

The Uplift of Soil Nutrients by Plants: Biogeochemical Consequences across Scales (JOBBÁGY and JACKSON, 2004)

Plant Soil Interactions in Multistrata Agroforestry in the Humid Tropics (SCHROTH et al., 2001)