scholarly journals Towards understanding the role of ectomycorrhizal fungi in forest phosphorus cycling : a modelling approach

2018 ◽  
Vol 64 (2) ◽  
pp. 79-95 ◽  
Author(s):  
Michiel F. Bortier ◽  
Enrique Andivia ◽  
José G. Genon ◽  
Tine Grebenc ◽  
Gaby Deckmyn
Keyword(s):  
Ectomycorrhizal Fungi ◽  
Nutrient Availability ◽  
Forest Ecosystem ◽  
P Uptake ◽  
Forest Growth ◽  
Growth And Yield ◽  
Management Scenarios ◽  
Soil P ◽  
Growth And Yield Models

Abstract Many studies have shown the importance of ectomycorrhizal fungi (EM) in forests both for nutrient availability and for carbon (C) and nutrient cycling in the soil. Yet so far they are not incorporated in forest ecosystem growth and yield models. Recent research suggests phosphorus (P) shortage could be a major constraints to forest productivity in the future. For a realistic simulation of future forest ecosystem functioning, inclusion of detailed soil P cycling and the trees-EM interaction is necessary. We developed a full ecosystem P model that simulates P uptake by roots and EM, allocation within trees, physiological deficiency effects on C assimilation and allocation, release through litter decomposition, coupled with water, C and nitrogen (N) fluxes accounted for in the mechanistic forest stand model ANAFORE. Our results confirm the importance of incorporating EM in forest ecosystem models and suggest that the lack of incorporation of P in models may result in an under- or overestimation of forest growth. This new model has the potential of being used to assess the response of trees and/or stands to nutrient availability under different climate and management scenarios. With the current parameterization it is functional as a scientific research tool to investigate hypotheses.

A simple growth and yield model for assessing changes in standing volume across Canada’s forests

2009 ◽  
Vol 85 (1) ◽  
pp. 57-64 ◽  
Author(s):  
C -H. Ung ◽  
P Y Bernier ◽  
X J Guo ◽  
M -C. Lambert
Keyword(s):  
Predictive Power ◽  
Robust Regression ◽  
Forest Growth ◽  
Growth Potential ◽  
Growth And Yield ◽  
Stand Age ◽  
Yield Model ◽  
Wood Volume ◽  
National Model ◽  
Growth And Yield Models

We have adjusted two growth and yield models to temporary sample plots from across Canada, and used climate variables in lieu of phytometric indices such as site index to represent, in part, the site-level variability in growth potential. Comparison of predicted increments in plot-level height, basal area and merchantable wood volume to increments of these variables measured in permanent sample plots shows a moderate to poor predictive ability. Comparison with the performance of four operational growth and yield models from different provinces across Canada shows comparable predictive power of this new model versus that of the provincial models. Based on these results, we suggest that the simplification of regional growth and yield models may be achieved without further loss of predictive power, and that the large error in the prediction of growth increment is mostly associated with the use of temporary sample plots which, by definition, contain little information on stand dynamics. We also suggest that, because of the empirical nature of these growth and yield models, the scale of application should determine the appropriate scale of the model. National estimates of forest growth are therefore less likely to be biased if obtained from a national model only than if obtained from a combination of regional models, where those exist, gap-filled with estimates from a national model. Key words: yield model, merchantable wood volume, stand age, climatic variables, simultaneous regression, robust regression

scholarly journals Simulating ectomycorrhizal fungi and their role in carbon and nitrogen cycling in forest ecosystems

2014 ◽  
Vol 44 (6) ◽  
pp. 535-553 ◽  
Author(s):  
G. Deckmyn ◽  
A. Meyer ◽  
M.M. Smits ◽  
A. Ekblad ◽  
T. Grebenc ◽  
...  
Keyword(s):  
Ectomycorrhizal Fungi ◽  
Forest Ecosystem ◽  
State Of The Art ◽  
Forest Growth ◽  
Ecosystem Models ◽  
Carbon And Nitrogen ◽  
The Past ◽  
Starting Point ◽  
Insight Into ◽  
Ecological Functioning

Although ectomycorrhizal fungi play an important role in forest ecosystem functioning, they are usually not included in forest growth or ecosystem models. Simulation is hampered by two main issues: a lack of understanding of the ecological functioning of the ectomycorrhizal fungi and a lack of adequate basic data for parameterization and validation. Concerning these issues, much progress has been made during the past few years, but this information has not found its way into the forest and soil models. In this paper, state-of-the-art insight into ectomycorrhizal functioning and basic values are described in a manner transparent to nonspecialists and modelers, together with the existing models and model strategies. As such, this paper can be the starting point and the motivator to include ectomycorrhizal fungi into existing soil and forest ecosystem models.

scholarly journals Cow Manure Application Cuts Chemical Phosphorus Fertilizer Need in Silage Rice in Japan

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1483
Author(s):  
Thanh Tung Nguyen ◽  
Yuka Sasaki ◽  
Mitsuhiko Katahira ◽  
Dhirendranath Singh
Keyword(s):  
P Uptake ◽  
Growth And Yield ◽  
Cow Manure ◽  
Phosphorus Fertilizer ◽  
Manure Application ◽  
Soil P ◽  
Olsen P ◽  
P Fertilizer ◽  
P Balance ◽  
Total P

Cow manure is a good source of phosphorus (P). Here, we investigated whether the amount of P fertilizer can be reduced when cow manure is applied to paddy soil based on growth, P uptake, yield, and soil P status evaluation. Treatments included unfertilized control (CK); manure plus chemical nitrogen (N), potassium (K), and P fertilizer (MNK P); MNK and 75% P (MNK ¾ P); MNK and 50% P (MNK ½ P); MNK and 25% P (MNK ¼ P); and MNK. Manure was applied at the rate of 10 t ha−1 in fresh weight base. The P fertilizer was applied at 34.9 kg P ha−1 as full dose. Treatment with MNK resulted in the same growth, P uptake, and yield as that with the P fertilizer. P uptake and yield did not respond to P input from chemical fertilizer owing to high soil Olsen P levels. Moreover, MNK could maintain soil Olsen P and total P. Manure application resulted in a positive partial P balance. These results suggest that manure application can cut P fertilizer requirements in P-rich soils, while maintaining soil P for optimal rice growth and yield. By using cow manure in rice production, farmers can conserve finite P resources.

scholarly journals Role of Silicon in Mediating Phosphorus Imbalance in Plants

Plants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 51
Author(s):  
An Yong Hu ◽  
Shu Nan Xu ◽  
Dong Ni Qin ◽  
Wen Li ◽  
Xue Qiang Zhao
Keyword(s):  
Production Systems ◽  
P Uptake ◽  
Regulatory Function ◽  
Schematic Model ◽  
P Nutrition ◽  
Greenhouse Production ◽  
P Deficiency ◽  
Soil P ◽  
Underlying Mechanisms

The soil bioavailability of phosphorus (P) is often low because of its poor solubility, strong sorption and slow diffusion in most soils; however, stress due to excess soil P can occur in greenhouse production systems subjected to high levels of P fertilizer. Silicon (Si) is a beneficial element that can alleviate multiple biotic and abiotic stresses. Although numerous studies have investigated the effects of Si on P nutrition, a comprehensive review has not been published. Accordingly, here we review: (1) the Si uptake, transport and accumulation in various plant species; (2) the roles of phosphate transporters in P acquisition, mobilization, re-utilization and homeostasis; (3) the beneficial role of Si in improving P nutrition under P deficiency; and (4) the regulatory function of Si in decreasing P uptake under excess P. The results of the reviewed studies suggest the important role of Si in mediating P imbalance in plants. We also present a schematic model to explain underlying mechanisms responsible for the beneficial impact of Si on plant adaption to P-imbalance stress. Finally, we highlight the importance of future investigations aimed at revealing the role of Si in regulating P imbalance in plants, both at deeper molecular and broader field levels.

scholarly journals StandsSIM-MD: a Management Driven forest SIMulator

2016 ◽  
Vol 25 (2) ◽  
pp. eRC07 ◽  
Author(s):  
Susana Barreiro ◽  
João Rua ◽  
Margarida Tomé
Keyword(s):  
Forest Management ◽  
Tree Species ◽  
Growth Models ◽  
Planning Horizon ◽  
Md Simulations ◽  
Forest Growth ◽  
Growth And Yield ◽  
Management Approaches ◽  
User Friendly ◽  
Growth And Yield Models

Aim of the study: The existing stand level forest simulators available in Portugal were not developed with the aim of including up-to-date model versions and were limited in terms of accounting for forest management. The simulators’ platform, sIMfLOR was recently created to implement different growth models with a common philosophy. The objective was developing one easily-updatable, user-friendly, forest management and climate change sensitive simulator capable of projecting growth for the main tree species in Portugal.Area of the study: Portugal.Material and methods: The new simulator was programmed in a modular form consisting of several modules. The growth module integrates different forest growth and yield models (empirical and process-based) for the main wood production tree species in Portugal (eucalypt, umbrella and maritime pines); whereas the management module drives the growth projections along the planning horizon according to a range of forest management approaches and climate (at present only available for eucalypt).Main results: The main result is the StandsSIM-MD Management Driven simulator that overcomes the limitations of the existing stand level simulators. It is a step forward when compared to the models currently available in the sIMfLOR platform covering more tree species, stand structures and stand compositions. It is focused on end-users and it is based on similar concepts regarding the generation of required inputs and generated outputs.Research highlights:-          Forest Management Driven simulations approach-          Multiple Prescriptions-Per-Stand functionality-          StandsSIM-MD can be used to support landowners decisions on stand forest management-          StandsSIM-MD simulations at regional level can be combined with optimization routinesKeywords: Forest simulator, Forest Management Approaches; StandsSIM-MD; forest management.

scholarly journals Mycorrhizal effectiveness on physic nut as influenced by phosphate fertilization levels

2012 ◽  
Vol 36 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Elcio Liborio Balota ◽  
Oswaldo Machineski ◽  
Alexandra Scherer
Keyword(s):  
Mycorrhizal Fungi ◽  
Efficiency Index ◽  
P Uptake ◽  
Biofuel Production ◽  
Low Fertility ◽  
Growth And Yield ◽  
Physic Nut ◽  
Soil P ◽  
Mycorrhizal Effectiveness ◽  
Mycorrhizal Inoculation

In recent years, physic nut (Jatropha curcas L.) has attracted attention because of its potential for biofuel production. Although it is adapted to low-fertility soils, physic nut requires soil acidity corrections and addition of a considerable amount of fertilizer for high productivity. The objective of this research was to evaluate the effectiveness of arbuscular mycorrhizal fungi (AMF) (control without AMF inoculation, Gigaspora margarita inoculation or Glomus clarum inoculation) on increasing growth and yield of physic nut seedlings under different rates of P fertilization (0, 25, 50, 100, 200, and 400 mg kg-1 P soil) in greenhouse. The experiment was arranged in a completely randomized, block in a factorial scheme design with four replications. The physic nut plants were harvested 180 days after the beginning of the experiment. Mycorrhizal inoculation increased physic nut growth, plant P concentration and root P uptake efficiency at low soil P concentrations. The P use quotient of the plants decreased as the amount of P applied increased, and the P use efficiency index increased at low P levels and decreased at high P levels. Mycorrhizal root colonization and AMF sporulation were negatively affected by P addition. The highest mycorrhizal efficiency was observed when the soil contained between 7.8 and 25 mgkg-1 of P. The physic nut plants responded strongly to P application, independent of mycorrhizal inoculation.

scholarly journals Diameter-height models for the Terai tree species

2015 ◽  
Vol 25 (1) ◽  
pp. 50-54 ◽  
Author(s):  
A. Khadka ◽  
T. Subedi ◽  
M. Ghimire ◽  
B. P. Dhakal ◽  
H. Parikka
Keyword(s):  
Tree Species ◽  
Linear Models ◽  
Resource Assessment ◽  
Forest Growth ◽  
Growth And Yield ◽  
Forest Resource ◽  
Linear Mixed Effects ◽  
Shorea Robusta ◽  
Non Linear ◽  
Growth And Yield Models

Tree diameter-height relationship can be used as a key input component in forest growth and yield models, and description of stand dynamics. Various models of stem diameter and height relation were developed. Those were formulated and implemented during Terai forest inventory data calculations in the Forest Resource Assessment (FRA) Nepal Project. The field inventory was conducted from December, 2010 to March, 2011. The Concentric Circular Sample Plot was designed where the diameters at breast height of all the tallied trees and the heights of the sampled trees were measured. The data were handled with R-script in R Programme to generate non-linear mixed effects models in ‘lmfor’ package of forest biometrics functions of Mehtatalo. Different non-linear models were used to fit the diameter-height relation, which performed well in describing the relationships between the diameters and the heights of the Terai tree species depending on the sample size. The models were selected as the best fitted based on the statistical results such as standard error, Adjusted R2, RMSE and residuals. The best models for Shorea robusta and Terminalia alata were generated using Wykoff’s and Naslund’s functions, respectively.Banko Janakari, A Journal of Forestry Information for NepalVol. 25, No. 1Page: 50-54

Integrating biophysical controls in forest growth and yield predictions with artificial intelligence technology

2013 ◽  
Vol 43 (12) ◽  
pp. 1162-1171 ◽  
Author(s):  
M. Irfan Ashraf ◽  
Zhengyong Zhao ◽  
Charles P.-A. Bourque ◽  
David A. MacLean ◽  
Fan-Rui Meng
Keyword(s):  
Artificial Intelligence ◽  
Nova Scotia ◽  
Soil Water ◽  
Tree Growth ◽  
Forest Growth ◽  
Growth And Yield ◽  
Individual Tree ◽  
Artificial Intelligence Technology ◽  
Growth And Yield Models ◽  
Forest Growth And Yield

Growth and yield models are critically important for forest management planning. Biophysical factors such as light, temperature, soil water, and nutrient conditions are known to have major impacts on tree growth. However, it is difficult to incorporate these biophysical variables into growth and yield models due to large variation and complex nonlinear relationships between variables. In this study, artificial intelligence technology was used to develop individual-tree-based basal area (BA) and volume increment models. The models successfully account for the effects of incident solar radiation, growing degree days, and indices of soil water and nutrient availability on BA and volume increments of over 40 species at 5-year intervals. The models were developed using data from over 3000 permanent sample plots across the province of Nova Scotia, Canada. Model validation with independent field data produced model efficiencies of 0.38 and 0.60 for the predictions of BA and volume increments, respectively. The models are applicable to predict tree growth in mixed species, even- or uneven-aged forests in Nova Scotia but can easily be calibrated for other climatic and geographic regions. Artificial neural network models demonstrated better prediction accuracy than conventional regression-based approaches. Artificial intelligence techniques have considerable potential in forest growth and yield modelling.

Das nachhaltig verfügbare Holznutzungspotenzial im Schweizer Wald

2016 ◽  
Vol 167 (3) ◽  
pp. 162-171 ◽  
Author(s):  
Ruedi Taverna ◽  
Michael Gautschi ◽  
Peter Hofer
Keyword(s):  
National Level ◽  
Reference Value ◽  
Forest Growth ◽  
Long Term Effects ◽  
Management Scenarios ◽  
Additional Time ◽  
Basic Scenario ◽  
Economic Framework ◽  
Forest Growth Model ◽  
New Findings

The sustainably available wood use potential in Swiss forests Based on the most recent simulations created using the Massimo forest growth model, the sustainably available wood use potential in Swiss forests was calculated for five management scenarios for the next three decades as well as for two additional time periods in the future (to monitor the long-term effects). The term “sustainably available wood use potential” covers those wood quantities that could be put on the market, taking into account socio-ecological and economic restrictions on use. The sustainably available wood use potential is provided for production regions, priority functions as well as the assortment and qualities of timber. The previously used factors of the applied “onion” model were checked and modified, if necessary, in order to take new findings and current cost developments into consideration. The calculations for all scenarios come up with a sustainably available wood use potential that is much lower than in earlier investigations. Depending on the scenario and decade, sustainably available wood use potential accounts for less than 50% of the total use potential. The biggest decrease in total use potential was due to economic framework conditions. Turning to Switzerland as a whole, towards the end of the investigation period (2106) those scenarios including a sharp increase in use in the first three decades result in a sustainably available wood use potential that is clearly lower than the reference value used at the beginning of the simulation. In the basic scenario (constant stock) and in the scenario in which the form of management used to date (increasing stock) was simulated, the sustainably available wood use potential at national level remained more or less the same throughout the simulation period, ranging from 5 to 6 million m3 per year.

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