Forestry Model Research Articles

Regional aspects of forest management and reforestation

Subject. This article discusses the role of the forest complex' development in the advancement of industry and the economy as a whole, and the problem of maintaining a balance between deforestation and reforestation. Objectives. The article aims to analyze the trends in reforestation and changes in timber reserves in the Arkhangelsk Oblast. Methods. For the study, we used the general scientific research methods. Results. The article highlights the advantages of the site method of forest management and finds that the size of the allowable cutting area and the volume of timber harvesting in the Arkhangelsk Oblast are increasing, which has a positive impact on the economy of the Oblast. Conclusions. Thanks to the use of an intensive model of forestry, the forest complex of the Arkhangelsk Oblast is characterized by positive development dynamics. The practices of the Arkhangelsk Oblast can be used in other forest resourced regions of Russia, which will contribute to the preservation of the forest ecosystem as a whole.

The influence of tree species on small scale spatial soil properties and microbial activities in a mixed bamboo and broad-leaved forest

Soil enzyme activity and microbial biomass play a critical role in myriad ecological processes. Bamboo and broad-leaved mixed forests have received widespread attention as important forestry models for ecological restoration and sustainable development; however, our understanding the influences of broad-leaved tree species in mixed bamboo forests on soil properties and microbial activity remains unclear. Here we sampled twenty-seven spatially interspersed stands of bamboo-Castanopsis chinensis Hance mixed forest (CCB), bamboo-Alniphyllum fortune (Hemsl.) Makino mixed forest (AFB), and bamboo-Choerospondias axillaris mixed forest (CAB), with different mixing ratios (0–10 %, 10–20 %, 20–40 % canopy proportions) in subtropical China, to examine the effects of tree species and mixed ratio on soil nutrients, microbial biomass, and enzyme activity. We found that the different forests exhibited variations in soil nutrient levels. CAB forests exhibit notably higher mean C, N, and P contents than AFB and CCB, particularly at a 10–20 % mixing ratio where SOC concentration reached 46.50 g/kg. CAB forests demonstrated significantly higher activities of invertase (mean 701.83U/g), urease (8393.44U/g), and catalase (501.73U/g) compared to AFB and CCB forests, with peak enzyme activities observed at a 10–20 % mixing ratio. Soil microbial biomass C and N were notably greater in CAB and CCB forests than in AFB forests. CAB forests also exhibited the highest soil microbial biomass P (mean 48.68 mg/kg), which rose consistently with an increased mixing ratio. Multiple factor analysis revealed that the enzyme activities were significantly correlated with the annual growth of fine roots in the forest and were positively correlated with resident C, total N, total P, C: N, and C: P. Overall, the results provide insights into the importance of tree species and crown size in bamboo and broadleaved tree mixed forest in soil features and the microbial activity while providing management guidance for the selection of mixed tree species for sustainable management of bamboo forest soil microenvironment.

Method of designing forest road construction scenario with GIS-based calibration using sustainable forestry model

In Japan, where planted forest resources have matured, the growing demand for harvesting work has necessitated road network expansion. To address this challenge, a model grounded in graph theory was developed to design a road network aligned with Japan's environmental and social conditions. This model integrates the road network with a forest management plan to ensure that timber collection aligns with each year's business scenarios. The slope parameters in the model were fine-tuned using road network data from sustainable forestry locations and simulations were conducted in forests near Tokyo. The designed working road boasts an average slope of 13–14 %, and the final road network density, including primary roads, surpassed the city's development target of 85.08 m ha−1. An evaluation using the Hausdorff distance indicated that the road network layout was generally appropriate for actual data. These findings are expected to contribute significantly to the effective forest resource utilization.

Evaluating CO2 emissions in the residential sector: Life cycle assessment (LCA) using regional forestry design models in system dynamics (SD)

Evaluating CO2 emissions in the residential sector: Life cycle assessment (LCA) using regional forestry design models in system dynamics (SD)

POLA TANAM DAN SISTEM SILVIKULTUR PADA SKEMA PERHUTANAN SOSIAL DI KULON PROGO, D.I. YOGYAKARTA

Social forestry is a scheme chosen by the government to improve community welfare by providing legal access to communities to manage forests. One of the social forestry schemes implemented in Kulon Progo is Community Forestry. This scheme has great potential to be developed with a multi-use forestry management model. Therefore, a review of the silvicultural aspect is needed to understand the forest management model currently implemented. This research aims to identify tree species, planting patterns and silvicultural systems implemented by Community Forestry at Production Forests in Kulon Progo. The research was conducted from August to October 2023 in Plot 17 and Plot 19 of RPH Kokap, BDH Kulon Progo-Bantul. Observations were made by making measurement plots of 20 m x 40 m of each plot and then recording the name of tree species, coordinates, height, diameter, height without branches, and canopy width. The data were then analyzed using Spatially Explicit Individual-based Forest Simulator (SexI-FS) software version 2.1.0. to see the projected planting pattern. The results of the research showed that tree species planted in the Community Forestry were teak (Tectona grandis), acacia (Acacia mangium), mahogany (Swietenia macrophylla), eucalyptus (Eucalyptus sp.), paperback (Melaleuca leucadendron), and jackfruit (Artocarpus heterophyllus ). These species were planted using a mixed planting pattern with the silviculture system of selective logging with artificial regeneration.

The Impact of Forestry Industry Integration on the Forest Farmers' Income in China: A Theoretical and Empirical Study

Transforming the forestry development model and promoting the integrated development of the forestry industry has become an important way for forestry to break through development bottlenecks and achieve efficiency enhancement, prosperity of forest areas, and income increase for forest farmers. In this study, we have theoretically elaborated on the mechanism by which the integrated development of the forestry industry affects the income level of forest farmers. In terms of empirical research, we use the inter provincial panel data from 2005 to 2019 to empirically test the individual heterogeneity, regional heterogeneity, and spatial spillover effects of forestry industry integration on forest farmer income with the help of fixed effect model, quantile regression model and spatial panel model. Results showed that, firstly, the level of integration in the forestry industry is on the rise, with most provinces in the middle or high integration stage. Among them, the Northeast region has the highest level of integration. Secondly, there is a positive spatial correlation in the income of Chinese forest farmers, and the spatial correlation is gradually increasing. The income of forest farmers in coastal provinces is relatively high, as indicated by the presence of HH clusters. Thirdly, the integration of the forestry industry has significantly improved the income level of forest farmers, and there are group heterogeneity and regional differences. The heterogeneity of income is reflected in the increasing income effect of forestry industry integration, which continuously strengthens with the improvement of the income level of forest farmers. Regional heterogeneity is mainly manifested in the Northeastern, Eastern, and Central regions. The integration of forestry industries can significantly promote the growth of forest farmers’ income, while in the Western regions, the income increase effect of forestry industry integration has an inhibitory effect, but is not significant. Finally, the integration of the forestry industry has significant spatial spillover effect and the indirect effect is greater than the direct effect. However, the spillover effect coefficient is 0.007, which is still at a relatively low level, and the diffusion effect generated by factor flow still needs to be strengthened. Efforts to boost integrated forestry industry development will broaden the income channels of forest farmers by leveraging high productivity of the agglomeration effects, diffusion effect and demonstration effect, strengthening regional communication and cooperation, and promoting integrated forestry industry development with adjacent regions. This study helps to correctly grasp the relationship between forestry industry integration and farmers’ income, and provides decision-making reference for local governments to formulate policies for increasing farmers’ income in the development of forestry industry integration based on actual situations.

Forestry Scenario Modelling: Qualitative Analysis of User Needs in Lithuania

This paper aims to demonstrate the use of qualitative research methods, specifically in-depth interviews, to explore the intangible and often difficult-to-quantify needs for forestry scenario modelling in Lithuania, which are frequently not adequately perceived. The study involved informants representing key actors in forest policy, forest management, research, and education. A total of 21 informants from 11 different institutions, which hold significant power and expertise in forest decision making, were interviewed. The purpose of these interviews was to gather their perspectives on the potential forest decision support system in the country, aiming to address most of their needs. The interview questions explored various aspects, including the requirements for forestry scenario modelling, the desired level of detail and information content for decision making, and both functional and nonfunctional requirements for the scenario modelling system. It is worth noting that the expected functionality of the planned forest DSSs aligns with modern international standards. Nevertheless, the diversity of perspectives, wishes, visions, and intentions of key Lithuanian forestry actors regarding the aims, objectives, and essential functionality of forestry scenario modelling tools were identified. The understanding of the requirements for modern forest DSSs was greatly influenced by the current forestry paradigms in the country and the professional experiences of individual informants. In conclusion, our findings demonstrate that the utilization of qualitative research, particularly through in-depth interviews, has proven to be a highly effective tool for accurately specifying the requirements of a modern forest DSS. It helped mitigate preconceived notions and address gaps in the envisioned product, specifically by developing a framework of core solutions for the national forestry and land-use scenario modelling system.

Tree–litter–soil system C:N:P stoichiometry and tree organ homeostasis in mixed and pure Chinese fir stands in south subtropical China

IntroductionCultivation of Chinese fir (Cunninghamia lanceolata) have alleviated timber shortages and mixed stands with Chinese fir and indigenous species represent a sustainable forestry model. Studying system nutrient balance and tree nutrient homeostasis can provide insights into the ecological advantages of Chinese fir mixed stands and guide the management of plantations.MethodsMixed Chinese fir plantations with two native broadleaf species (Michelia macclurei and Mytilaria laosensis) and pure Chinese fir stands were examined for our study. The responses in carbon (C), nitrogen (N), and phosphorus (P) distribution and their stoichiometric characterization in the tree–litter–soil system to stand changes were evaluated. In addition, the ecological stoichiometric homeostasis of leaves, branches, trunks, bark and roots was used to measure the trees’ adaptive capacity to stand changes.ResultsThe results showed that the mixed stands of Michelia macclurei and Chinese fir significantly increased soil OC, TN, and TP, and improved the carbon sequestration and nutrient storage functions of the plantations. The mixed stands improved the litter mass and C:N and C:P to different degrees. The soil N and P imbalance reduced the leaf N:P, resulting in N limitation of different trees, while the principal component analysis showed that the improvement of soil TN in the mixed plantation alleviated the N limitation. In addition, mixed stands reduced N, P, and N:P homeostasis in branch, trunk, and bark of some Chinese fir trees, whereas mixed species showed flexibility in leaf N:P homeostasis.DiscussionTherefore, the selection of mixed species for mixed forests is a critical factor to consider when creating mixed plantations. These results contribute to our understanding of the ecological stoichiometry of fir plantations and are of considerable importance for the sustainable development of plantations as well as for the response to global climate change.

Community forestry in the Czech Republic – A historical throwback or a step forward?

The rising level of complexity and uncertainty in environmental governance highlights the interplay between governmental and non-governmental actors producing various forms of sustainable forest management, including community-based forestry, in which the relevance of small-scale private forest owners follows. In urban peripheries, community forestry principles shape small-scale private forest owners' activities. On an analytical level of small-scale private forest owners in Mladá Boleslav urban area, this paper uses the assumptions of the pluralist theory of democracy and resource mobilization theory in the context of community-based forestry to investigate the perceptions of the mobilization of material, human, and socio-organizational resources. It is in line with the policy objectives in the State Conception of Forest Policy 2035 issued by the Ministry of Agriculture of the Czech Republic. Its methodology is based on qualitative semi-structured interviews to gain in-depth results. The results showed that most small-scale private forest owners in urban areas perceived resource mobilization as a potentially beneficial mechanism for reaching a consensus and collective action. However, a functioning model for forest communities in urban areas is missing in the Czech Republic. This situation stems from the historical experience with socialism and the country's short tradition with a market economy. It implies historical prejudices and anthropocentric values among small-scale private forest owners. Lacking confidence in public policy processes and placing emphasis on interpersonal trust were also noticed during the research. The results open future avenues for discussion about the pathways for implementing community-based forestry models in urban areas in the Czech Republic.

基于线性规划与熵权TOPSIS法的农林牧渔结构最优化模型研究——以山东省为例

基于线性规划与熵权TOPSIS法的农林牧渔结构最优化模型研究——以山东省为例

A new index integrating forestry and ecology models for quantitatively characterizing forest carbon sequestration potential ability in a subtropical region

Due to the important role of forests in carbon neutrality, it is a big task in accurately calculating and predicting forest carbon storage and carbon sink capacity in recent years. However, considering the factors on the capacity of forest carbon sequestration, ecologists and foresters consider different models to evaluate the forest carbon sink ability at different scales, with foresters focusing more on forest growth models, while ecologists adding more climate and environmental factors, which may result in inconsistent results in carbon storage. Therefore, constructing an integrated model by combining the forestry and ecology models is essential for accurately quantifying and characterizing the forest carbon sink potential at the regional scale. Here, we proposed a new forest carbon sink potential index (FCSPI), which is defined as fractional deficiency of the current forest carbon to its maximum level, based on forest permanent plots, climate, and edaphic data to evaluate the forest sink potential ability from stand level to zonal scale across the northern subtropical zone in Hubei province, China, which coupled the stand growth model and climate-productivity model. The results at stand level showed that the R2 and RMSE of FCSPI were 0.78 and 0.072 respectively, which indicated that the FCSPI is an intuitive, highly practical, straightforward, easy, and rapid to implement methodology for forest carbon sequestration assessment. Moreover, FCSPI can conveniently extended from stand scale to zonal scale based on the site quality index for carbon sink (SIC) and stand age variables, which were derived from the opened climate, edaphic, and topographic data. The results of wall-to-wall FCSPI across the subtropical forest in Hubei province reveal the current and future carbon potential sequestration, which can help managers to focus on forest management for climate-smart actions and planning in forest ecosystem services framework.

Application of photovoltaics on different types of land in China: Opportunities, status and challenges

Addressing pressing issues such as global climate change, dwindling fossil fuel reserves, and energy structure transitions, there is a global consensus on harnessing photovoltaic (PV) technology. As PV projects burgeon, they intensify the demand for land resources. Given land's scarcity, its efficient use for PV becomes paramount. Delving into the interplay between PV and land unveils prospects for maximizing PV's potential and optimizing land use. Notably, in-depth studies spanning various land categories for PV applications remain limited. This research offers a comprehensive examination of China's land and water classification standards and policies, thoroughly investigating PV opportunities, its prevailing status, and challenges across diverse land types. It emphasizes PV application methodologies, commercial models, and specific case analyses, encompassing PV on agricultural land, construction land, inland and coastal waters, as well as sandy, saline, and mudflat regions. Results spotlight a surge in synergistic applications within agricultural photovoltaic complementary, fishery PV complementary, and forestry PV complementary models, which constitutes 76 % of all reviewed studies. Bolstered by supportive policies, rooftop PV research is also seeing a significant uptick. Conversely, studies on PV applications in deserted lands, unused terrains, and coastal waters are sparse, representing a mere 2 % of the total, pinpointing areas ripe for future exploration. Ultimately, this research furnishes invaluable insights into pioneering “PV + Land” strategies that promise both ecological and economic dividends, thereby facilitating cogent PV land-use planning, administration, and decision-making.

Evolutionary game analysis of forestry carbon sink trading model under blockchain technology

As a new balanced economy, the green economy guides the upgrade and transformation of industrial structures based on the original concept of sustainable development. Reducing carbon emissions is indispensable for achieving better and faster green economic development. From a functional perspective, forestry carbon sinks have good carbon sequestration potential and have positive attributes, such as climate regulation and biodiversity maintenance, for the entire ecosystem. To promote the continuous development of forestry carbon sink trading in China, blockchain, a new technology with several advantages such as traceability, supervision, and tamper-proofness, has emerged, which creates a good market trading environment and has made a breakthrough in the trading mode. If forestry carbon sink trading is effectively supported, organic combinations and simultaneous synergistic development can be conducted, which will open new avenues for the carbon sink economy. In this study, a game model of the forest carbon sink trading mode under blockchain technology was constructed from the perspective of traders, and influential factors, such as the carbon sink available for sale by the supply side and the demand side's perspective towards emission reduction, were considered. Subsequently, the MATLAB R2020b software was used to conduct a simulation analysis of the transactions, thereby showing the evolutionary path of the game between the two sides and the influence mechanism of the addition of blockchain technology on the evolution trajectory of the demand-side decision. The findings indicate that, from the perspective of participating traders, the inclusion of blockchain technology in forestry carbon sink trading resulted in positive effects. Moreover, the greater the probability that the carbon sinks available for sale in the market can meet the demand, the more likely the demand side is to participate in the transaction.

Simulation tools for net-positive process design: Trees as unit operations for carbon sequestration and air quality regulation

Chemical processes have significant environmental and societal impacts, such as climate change and human health, due to air and water pollution. In addition, chemical processes consume unsustainable amounts of natural ecosystems’ goods and services. Engineers have tried to address these challenges by reducing waste, integrating processes, and minimizing the consumption of raw materials and energy. However, these efforts have not been enough to address the impact of the process on natural ecosystems and local communities. Hence, the need to integrate ecological systems into traditional engineering design to provide sustainable and cost-effective solutions. Although models for ecological systems are readily available in the literature, engineers are hesitant to utilize these models without familiar tools and the traditional undervaluation of ecosystem services’ role and the uncertainty of their performance. To overcome some of these barriers, ecosystems can be classified as unit operations since they can be designed to achieve specific tasks. This work focuses on integrating vegetation as unit operations in process design to remove air pollutants and sequester carbon. We developed a practitioner-friendly simulation module in CHEMCAD that utilizes sophisticated rural and urban forestry models developed by the online i-Tree assessment tool. We demonstrate the module through a power plant case study and highlight some alternative spatially explicit integrated designs that are environmentally and economically superior.

Assessment of Potential Prediction and Calibration Methods of Crown Width for Dahurian Larch (Larix gmelinii Rupr.) in Northeastern China

Crown width (CW) is an important indicator for assessing tree health, vitality, and stability, as well as being used to predict forestry models and evaluate forest dynamics. However, acquiring CW data is laborious and time-consuming, making it crucial to establish a convenient and accurate CW prediction model for forest management. In this study, we developed three models capable of conducting calibration: generalized models (GM), quantile regression models (QR), and mixed-effects models (MIXED). The aim was to effectively improve the prediction accuracy of CW using data from Dahurian larch (Larix gmelinii Rupr.) in Northeastern China. Different sampling designs were applied, including selecting the thickest, thinnest, intermediate, and random trees, with 1 to 10 sample trees for each design. The results showed that all models achieved accurate CW predictions. MIXED displayed the most superior fitting statistics than GM and QR. In model validation, with the increase in the number of sample trees, the model prediction accuracy gradually improved and the model differences gradually reduced. MIXED produced the smallest RMSE, MAE, and MAPE across all sampling designs. The intermediate tree sampling design with the best validation statistics for the given sample size was selected as the final sampling design. Under intermediate tree sampling design, MIXED required a minimum of five sample trees, while GM and QR required at least five and six sample trees for calibration, respectively. Generally, we suggested selecting MIXED as the final CW prediction model and using the intermediate tree sampling design of five trees per plot. This study could provide ideas and support for forest managers to accurately and efficiently predict CW.

Logs or permits? Forestry land use decisions in an emissions trading scheme

AbstractNegative carbon emissions options are required to meet long‐term climate goals in many countries. One way to incentivise these options is by paying farmers for carbon sequestered by forests through an emissions trading scheme (ETS). New Zealand has a comprehensive ETS, which includes incentives for farmers to plant permanent exotic forests. This research uses an economy‐wide model, a forestry model and land use change functions to measure the expected proportion of farmers with trees at harvesting age that will change land use from production to permanent forests in New Zealand from 2014 to 2050. We also estimate the impacts on carbon sequestration, the carbon price, gross emissions, GDP and welfare. When there is forestry land use change, the results indicate that the responsiveness of land owners to the carbon price has a measured impact on carbon sequestration. For example, under the fastest land use change scenario, carbon sequestration reaches 29.93 Mt CO2e by 2050 compared to 23.41 Mt CO2e in the no land use change scenario (a 28% increase). Even under the slowest land use change scenario, carbon sequestration is 25.89 Mt CO2e by 2050 (an 11% increase compared with no land use change). This is because, if foresters decide not to switch to permanent forests in 1 year, carbon prices and ultimately incentives to convert to permanent forests will be higher in future years.

“Profitability is sustainability:” framing of forest management practices by the Swedish forest industry

ABSTRACT This article investigates how the Swedish forest industry, as represented by the three largest Swedish private forest companies (Svenska Cellulosa AB, Stora Enso, and Holmen), through their main public relations (PR) channels frame the current dominant Swedish forestry model and alternative models that are promoted by the European Union (EU). The content analysis of the three companies’ trade magazines published between 2019 and 2022 explores the patterns in the PR framing of the forest management models with respect to economic, environmental, and social aspects. The time interval is centered by the July 2021 announcement of the EU's new Forest Strategy for 2030. The magazines’ target audience is private forest owners, from whom Svenska Cellulosa AB, Stora Enso, and Holmen buy 40–50% of the timber used in production. The main finding of the study is that these corporations did not present alternative methods as viable options to replace the Swedish forestry model. The magazines, with some individual variations, respond to the alternative methods promoted by the EU and environmental associations by an increased emphasis on the benefits, mainly environmental, of the Swedish forestry model – framing the model as not only the most profitable but also the most ecologically sustainable.

Allometric tree volume models for Pinus roxberghii and Cedrus deodara in Karnali Province, Nepal

Effective forest management is based on information, such as current growing stock and its future state, which is provided by various forestry models, including tree volume models. Tree volume models are essential tools for estimating growing stock, carbon accounting, timber valuation, identifying forest stands to harvest, growth and yield modeling, and forest ecosystem analysis. We developed tree volume models for two important tree species (Pinus roxberghii Sarg. and Cedrus deodara Roxb.) in Nepal using data from many individuals (mature trees and juveniles) representing wide variations of tree volume allometry. We used diameter at breast height, total height, and crown width of the individuals as predictors in tree volume models for Pinus roxberghii while only the former two predictors in the models for Cedrus deodara. All the mathematical functions described more than 91% and 97% tree volume variations for Cedrus deodara and Pinus roxberghii, respectively. Models for Pinus roxberghii revealed almost similar effect of crown width as tree height on tree volume allometry. Models for this species can be applicable for predicting tree volume with and without bark; however, models for Cedrus deodara can only predict the over-bark tree volume. Testing Pinus roxberghii model against external independent data confirmed a high accuracy of the model. The proposed tree volume models for the species of interest are biologically plausible and statistically robust, and therefore, can be applied to estimate the growing stock precisely, carbon accounting, timber valuation, forest growth and yield modeling. However, users need to apply the model with caution for the forest conditions not covered by modeling data for Cedrus deodara. The prediction accuracy of the models can be further improved through recalibration with additional data collected from wider distributions of the species of interest across the Karnali province and beyond, and application of more robust modeling methods, such as mixed-effects modeling and machine leaning.

Stochastic Mitra–Wan forestry models analyzed as a mean field optimal control problem

Stochastic Mitra–Wan forestry models analyzed as a mean field optimal control problem

The Compound Forest–Medicinal Plant System Enhances Soil Carbon Utilization

The sensible use of forest resources and the sound management of forests have become increasingly important throughout the years. In keeping with the trend, a composite forestry operation model has emerged. Traditional Chinese culture and forest management are particularly intertwined in China. Thus, use of the forest–medicine compound management model is recommended. The majority of research on the management of forest–medicine compounds has focused on how to grow more effective medicinal plants, ignoring the effects of the chemicals used on the soil environment, particularly the soil micro-environment. A forest–medicine system was established in South China to investigate the impacts of planting Aspidistra elatior on the variety of rhizospheric microorganisms and their ability to use carbon sources. In the plots with or without A. elatior, three dominant plants (Castanopsis hystrix, Psychotria rubra, and Ficus hirta) grew soil rhizosphere microbes, which were analyzed using Biolog EcoPlates. The study found that planting medicinal plants in the understory improved the soil’s nutritional content, increased the inter-root microbial communities of other medicinal plants, and enhanced the microbes’ ability to use soil carbon sources. The forest–medicine complex model, which rationalizes the use of forest clearings and generates economic and ecological benefits, can significantly increase the quantity of dominant microorganisms and enhance the enrichment of other species, resulting in a positive impact on the soil environment. These findings suggest that the forest–medicine compound management model can improve the use of soil carbon sources throughout the forest system.