Silvicultural Operations Research Articles

Estimation of within-gap regeneration height growth in managed temperate deciduous forests using bi-temporal airborne laser scanning data

Key messageMulti-temporal airborne laser scanning (ALS) data were used to estimate regeneration stem height growth within gaps in uneven-aged deciduous forests. The height and height growth measured in the field were used to calibrate and validate ALS estimates. This method provided highly precise estimates of height and unbiased height increment estimates of regeneration at stem level.ContextAssessing regeneration height growth is essential for evaluating forest dynamics and optimizing silvicultural operations. However, regeneration description at high spatiotemporal resolution has remained limited to restricted areas by the limiting cost constraints of field measurements. Highly precise airborne laser scanning (ALS) data are currently acquired over wide areas. Such datasets are promising for characterizing regeneration dynamics.AimsWe aimed to estimate height and height growth within regenerating areas at the stem level using multi-temporal ALS data.MethodsALS data were acquired from 56,150 ha of uneven-aged deciduous forest in Belgium in 2014 and 2021. Stem tops were detected using local maxima (LM) within regenerating areas in both ALS datasets and matched. Field data were collected in 2021 and used to calibrate the ALS-estimated heights using linear and non-linear models at stem level. Height growth estimation was then validated using field-measured increments.ResultsWithout height calibration, the 2021 ALS-estimated height had a − 1.06 m bias and 1.39 m root-mean-squared error (RMSE). Likewise, the 2014 ALS-estimated height had a − 0.58 m bias and 1.14 m RMSE. The non-linear calibration seemed more appropriate for small regeneration stems (height < 4 m). Using height calibration, the 2021 ALS-estimated height had a − 0.01 m bias and 0.84 m RMSE. In 2014, the bias and RMSE were 0.02 and 0.91 m, respectively. ALS-estimated height growth was unbiased and had an RMSE of 0.10 m·year−1.ConclusionsThis original method is based on the bi-temporal ALS datasets calibrated by limited field measurements. The proposed method is the first to provide unbiased regeneration height growth of regeneration stems in uneven-aged forests and new perspectives for studying and managing forest regeneration.

Allometric equations for biomass and carbon pool estimation in short rotation Pinus radiata stands of the Western Cape, South Africa

AbstractThe quantification of tree growth and carbon storage over time is an important task for sustainable forest management and carbon sequestration projects. For the South African short-rotation Pinus radiata (D. Don) forests, this knowledge is lacking. We developed allometric equations and compared the estimated weights to previously published biomass studies and we used Dirichlet Regression (DR) modelling to ensure additivity of the component proportions. The biomass components and their contribution to carbon storage depend strongly on forest structure and mean tree size but also on-site conditions and tree architecture. Our first two hypotheses were that the (1) best model for stemwood (SW), bark and total mass will include the combined variable DBH2H and (2) that the DR will yield statistically similar estimates for all components when compared to the best models. Our third hypothesis was that allometric equations developed for sites with high resource availability (e.g. wet, fertile sites) will yield biased estimates when extrapolated to sites with lower levels of resource availability (drier and/or infertile sites). The results indicated that DBH2H was the best variable to describe SW, bark and total mass and the DR yield similar estimates for all component proportions when compared to the best models. There were strong similarities in the SW and total mass of independent test sites in comparison to the SW and total mass of this study but greater variability in the bark, needle and branch mass. This can be associated to site and seasonal differences as well as variability in tree architecture brought about by different silvicultural operations on individual sites. Previously developed equations by other authors for sites with high resource availability overpredicted the SW and total mass of the models developed in this study. Our set of additive component equations performed well even when applied to sites of similar productivity over a climate gradient. The presented new equations bridge the gap in knowledge where allometric equations for short rotation Radiata pine stands are lacking.

Infected nursery stock and poor silvicultural practices contribute to development of Ceratocystis manginecans wilt and canker disease in Eucalyptus pellita

In Indonesia and Malaysia, Eucalyptus pellita has replaced large areas of Acacia mangium plantations as the latter species is highly susceptible to C. manginecans. This strategy may not be effective in the long term as E. pellita is also susceptible to Ceratocystis wilt and canker disease though it has higher tolerance than A. mangium. Furthermore, the pathogen has the capacity to evolve and adapt to new hosts. To highlight the need for careful sanitation in nurseries and the potential impact of wounding during silvicultural operations, two experiments were conducted to (i) demonstrate the ability of cryptic Ceratocystis infections in nursery plants to develop into Ceratocystis wilt and canker disease after planting out and (ii) assess the risk of Ceratocystis infection and disease development from different wound types. In the nursery, three-month-old mini-cuttings of seven E. pellita clones were artificially wounded and inoculated with two isolates of Ceratocystis manginecans near the base of the stem. The disease incidence and lesion length were measured one month later, just prior to planting out. After four months of growth in the plantation, the trees were harvested and stems sliced longitudinally to measure the length of xylem discolouration. Six of 36 ramets of susceptible clones died and the length of xylem discolouration was significantly greater in susceptible clones than in tolerant clones. The second experiment was based on inoculation of 12-month-old plantation-grown trees of one clone of E. pellita with one isolate of C. manginecans using six different wounding methods. The inoculated wounds on the trees all produced xylem discolouration, except for those that only penetrated the outer bark. Disease incidence was greater at stem heights of 30 to 90 cm than on the basal stem or branch stub. The experiment emphasised the importance of minimising the risk of C. manginecans infection following wounding in the nursery and in the field as the discolouration is an indication of xylem blockage that can lead to tree mortality.

Drivers of snag fall rates in Fennoscandian boreal forests

Abstract Persistence of standing dead trees (snags) is an important determinant for their role for biodiversity and dead wood associated carbon fluxes. How fast snags fall varies widely among species and regions and is further influenced by a variety of stand‐ and tree‐level factors. However, our understanding of this variation is fragmentary at best, partly due to lack of empirical data. Here, we took advantage of the accruing time series of snag observations in the Finnish, Norwegian and Swedish National Forest Inventories that have been followed in these programs since the mid‐1990s. We first harmonized observations from slightly different inventory protocols and then, using this harmonized dataset of ca. 43,000 observations that had a consistent 5‐year census interval, we modelled the probability of snags of the main boreal tree species Pinus sylvestris, Picea abies and Betula spp. falling, as a function of tree‐ and stand‐level variables, using Bayesian logistic regression modelling. The models were moderately good at predicting snags remaining standing or falling, with a correct classification rate ranging from 68% to 75% among species. In general, snag persistence increased with tree size and climatic wetness, and decreased with temperature sum, advancing stage of decay, site productivity and disturbance intensity (mainly harvesting). Synthesis and applications: The effect of harvesting demonstrates that an efficient avenue to increase the amount of snags in managed forests is protecting them during silvicultural operations. In the warmer future, negative relationship between snag persistence and temperature suggests decreasing the time snags remain standing and hence decreasing habitat availability for associated species. As decomposition rates generally increase after fall, decreasing snag persistence also implies substantially faster release of carbon from dead wood.

Potential of Lightweight Drones and Object-Oriented Image Segmentation in Forest Plantation Assessment

Forests play a vital role in maintaining ecological balance and provide numerous benefits. The monitoring and managing of large-scale forest plantations can be challenging and expensive. In recent years, advancements in remote sensing technologies, such as lightweight drones and object-oriented image analysis, have opened up new possibilities for efficient and accurate forest plantation monitoring. This study aimed to explore the utility of lightweight drones as a cost-effective and accurate method for mapping plantation characteristics in two 50 ha forest plots in the Nayla Range, Jaipur. By combining aerial photographs collected by the drone with photogrammetry and limited ground survey data, as well as topography and edaphic variables, this study examined the relative contribution of drone-derived plantation canopy information. The results demonstrate the immense potential of lightweight drones and object-oriented image analysis in providing valuable insights for optimizing silvicultural operations and planting trees in complex forest environments.

An Eco-Dendrometric Study of Atlas Cedar (Cedrus Altantica Manetti) from Theniet-El-Had National Park (North West of Algeria)

Purpose: This work contributes to the study of the growth pattern of Atlas Cedar (characterized by dendrometric variables) relevant to the stands from Pepinière canton in relation to site factors (ecological and pedology descriptors). Theoretical framework: A forest ecosystem is a complex set of external factors that have a positive or negative effect on tree growth. Species ecology is a key point in understanding their behavior in relation to environmental fluctuations. Method: Forty-six temporary plots were set up to collect ecological, pedological, and dendrometric data, allowing for a characterization of the growth pattern of Atlas Cedar stands. Results and conclusion: The study highlights the presence of an unmanaged irregular forest. Despite being located in an environment conducive to its growth, this forest is subject to degrading anthropogenic activity. Analysis of variance at a significance level of 95% shows that altitude and limestone content are the main site factors influencing Atlas Cedar growth. Research implications: knowledge of the growth rate of this species allows better silvicultural operations, and application of more adequate management plans for this endemic protected species. Originality/value: This study constitutes a reliable scientific tool for forest managers, particularly in national reforestation plans, which are doomed to failure due to a lack of knowledge of the behavior of the species used.

Implications of incorrectly determining site index on stand-level management activities and financial returns in older generation loblolly pine plantations

Predicting future yields normally requires an estimate of site quality. A commonly used measure is site index (SI). SI is often incorrectly quantified operationally due to the ambiguity associated with selecting “site” trees. Plus, error in the measurement of height itself occurs. This study quantifies the impacts on the number and timing of thinnings, and the final harvest ages, as well as financial returns when incorrectly determining SI. Three values of SI (base age 25 years) were examined using two older generation loblolly pine plantation growth and yield simulation models from the Western Gulf, USA; 16.76 m, 21.34 m, and 25.91 m. Firstly, a particular SI was assumed to be the “true” value, growth and yield estimates were obtained, and financial assessments were conducted. The same process was then conducted again, but assuming that the SI was incorrectly determined by varying positively and negatively the SI by up to 1.22 m from the assumed “true” value. For these older generation plantations, incorrectly determining SI did impact the age of the first thinning by as much as 5 years. In some cases, errors of +/- 1.22 m in SI estimation had little impact on the estimated timing of the first thinning. Errors in SI of up to +/- 1.22 m had little impact on the number of thinnings across economic rotation ages. For both unthinned and twice-thinned stands, final harvest (clearcut) ages differed by as much as 4 years for SI errors up to +/- 1.22 m. These errors led to differences in Land Expectation Value (LEV) up to $406.50 ha-1. Across the three SI (16.76, 21.34, and 25.91 m), differences in LEV ranged from $237.49 to $406.50 ha-1. These differences in LEV could be enough to incorrectly not conduct, or incorrectly conduct, a silvicultural operation such as an herbicide treatment or a fertilization treatment across a rotation, among other treatments.

Identification of functional traits responsible for environmental vulnerability of Cedrus deodara in temperate forests of Western Himalaya

Climate change is impacting forest tree species adversely and making the ecological system vulnerable. The present study attempts to assess the internal vulnerability of Cedrus deodara occurring in nine sub-types of temperate forests in Western Himalaya, India via a plant functional trait-based approach. Internal vulnerability was assessed based on sensitivity and adaptive capacity through proposing an index using IPCC framework. Sensitivity was determined based on various traits (indicators) of light harvesting, carbon assimilation, nutrient content, and water budget, whereas adaptability was defined based on light harvesting efficiency, water use efficiency, resource use efficiency, and nutrient limitation. Sensitivity was maximum in Dry Deodar Forest (0.51) and Low-Level Blue Pine Forest (0.51) and minimum in Western Mixed Coniferous Forest (o.38), however adaptability was maximum in Kharsu Oak Forest (0.65) and Moist Deodar Forest-II (0.65) with minimum adaptability for Ban Oak Forest (0.53). In Ban Oak Forest, Low-Level Blue Pine Forest and Moist Deodar Forest-II high stomatal conductance compensates the low chlorophyll achieving homeostasis state for photosynthesis. Negative minimum temperature (-6.95 to −2.04 °C) in winters followed by high monsoon rainfall (417.74 to 1256.13 mm) causes high sensitivity amongst the C. deodara population in Low Level Blue Pine Forest, Dry Deodar Forest and Moist Deodar Forest-II; and adaptability was majorly affected by water availability i.e., excessive monsoon rainfall in Ban Oak Forest (1962.45 mm) and least rainfall in Neoza Pine Forest (349.50 mm). Overall, the vulnerability was high in Low Level Blue Pine Forest (0.46), Ban Oak Forest (0.45) and Dry Deodar Forest (0.45). Present study identified key traits for species vulnerability therefore management intervention should orient towards those silvicultural operations which may reduce relative water use of the species and may also facilitate for improved photosynthesis i.e., through water provision and density management of the C. deodara dominated forests in Himalayan region. The study concludes that a unified approach for managing species of the forest may be disadvantageous and detrimental to forest conservation. Rather site-specific management approach, which led to incremental response to the identified traits may support the conservation of species.

Ranking Research and Development Needs of Silvicultural Operations for a Plantation Forestry Cooperative

Forest Owners Organizations can help small- and medium-scale private landowners stay competitive by conducting and sharing research and development (R&D) activities. This study evaluated R&D needs for silvicultural operations to inform an R&D strategy for the cooperative. Individual and group priorities were collected using the Analytical Hierarchy Process via a web survey and web meeting. Consensus in priorities was followed by an assessment of the cooperative's capacity to carry out in-house research. Two regional managers, eight plantation managers and one R&D/Technology manager participated in one or more stages of the process. Participants ranked most silvicultural operations similarly. However, the variation was largest for harvest residue, seedling, and stump management. Minor regional differences were found but both regions (south and north) had “very high” group consensus indicators (86.2% and 89%, respectively). The group decision ranked R&D in harvest residue management as the highest priority, followed by soil preparation and planting methods. The cooperative's strongest capacity for in-house research was in the execution of the experimental design to address the research questions (implementation). The weakest research capacity was found in terms of harvest residue, seedling, and stump management. Hence, the cooperative is dependent on research institutions. These findings can be used to inform and align the cooperative's R&D strategy, investments, and their research collaborations.

Woody Plant Diversity of Tropical Dry Deciduous Forest of Ranchi, Jharkhand

The study was conducted to determine the composition and diversity of three different growth stages of plant in tropical dry deciduous forest in Horhap under Mahilong Range, Ranchi during the year 2018- 2019. The entire area was divided into two sites based upon the physiographic factors. The simple random sampling procedure was followed with quadrates of 10×10 m2 for trees and saplings and 2×2 m2 quadrates for seedlings were taken. A total of 1430–1810 stems ha-1 in trees, 1080–1240 stems ha-1 in saplings and 45500–56500 stems ha-1 in seedlings were encountered. The total basal area was varied between 35.97 to 48.01 m2 ha-1 for trees, 4.67 to 5.42 m2 ha-1 for saplings and 3.78– 3.88 m2 ha-1 for seedlings. Shorea robusta showed highest value of IVI in tree sapling and seedling layers. Shannon index ranged from 2.43–2.97 for trees, 3.07–3.08 for saplings and 2.21–2.26 for seedlings. The concentration of dominance was 0.24–0.33 for trees, 0.19–0.21 for saplings and 0.37–0.4 for seedlings. Equitability ranged from 0.92–0.99 for trees, 1.0 for saplings and 0.84–0.86 for seedlings. Species richness ranged from 1.79–2.53 for trees, 2.11–2.43 for saplings and 1.19–1.21 for seedlings. However there is a need for ideal silvicultural operations and scientific approach-based management practice to retain the diversity ultimately a healthy forest ecosystem.

Assessing the Efficacy and Efficiency of Subsidiary Silvicultural Operations in Sal Forest of Jharkhand; Measuring the Impact in terms of Ecosystem Services

Assessing the Efficacy and Efficiency of Subsidiary Silvicultural Operations in Sal Forest of Jharkhand; Measuring the Impact in terms of Ecosystem Services

Modelling the influence of thinning intensity and frequency on the future provision of ecosystem services in Mediterranean mountain pine forests

Thinnings are silvicultural operations that repetitively reduce tree density to improve the vigour of the remaining trees and the economic benefits of the stands. Thinning can also enhance the provision of various ecosystem services throughout the rotation period. In this study, we use a modelling approach to evaluate stand dynamics and the provision of ecosystem services (mushroom production, wood for timber, carbon storage, blue water, and habitat for biodiversity) in Mediterranean mountain pine forests. We simulated thirteen thinning regimes—defined by intensity and frequency—under two different climate change scenarios. We implemented the thinning regimes using SORTIE-ND, an individual-based model of forest dynamics, and then we used models developed for the study area to calculate the provision of services. We used as a case study Pinus sylvestris and Pinus nigra stands, and we evaluated the effect of the thinning regime, climate change, and forest type over 100 years. Our simulations suggest that the production of timber and carbon decreased with increasing intensity and shortening frequency of thinnings, while the provision of mushrooms and blue water generally increased under those conditions. Large timber was better supported by a thinning regime with heavy intensity and shorter frequencies, which also favoured the rapid presence of large dead trees (dbh > 30 cm) in the stand. We found synergies between the production of timber and carbon, while the provision of mushrooms and particularly blue water were in a trade-off relationship with these services. Our simulations show that climate change will lower the production of ecosystem services under the most severe climate predictions and alter the effect of different regimes on the provision of services. We conclude that our modelling approach is a useful and efficient tool for answering questions that would otherwise require long-term studies, and that it can provide useful information to guide management efforts to adapt forest management to the challenges of climate change.

Exploring the relevance of community forest operational plan: users’ perspective and implementation status

Community Forestry has long been considered an epitome of decentralized forest management in Nepal. The management of Community Forests are guided by their Operational Plans (OPs), the mandatory technical document. Their preparation demands substantial human and economic inputs. However, their extent of implementation and the significance of these plans to local user are topics of debate. In this context, this study analyzes users' perception about the OP and their implementation status. We took case study approach and conducted key informant interview (n=25), focus group discussion (n=16) and purposive household survey (n=246) in 15 Community Forest User Groups to compile required data. The perceptions were analyzed using qualitative methods. The results revealed that the users have poor understanding of their plans and considered the plan as technical legitimate documents. The implementation status of the plans was of sub-standard. Silvicultural operations prescribed in the operational plans were insufficiently carried out. We found that the users are adopting only the forest product harvest and utilization aspects of the plans. Provided the poor understanding of OPs among the users and quality of plan implementation, this study questions the relevance of current operational plans and emphasizes the need of reviewing the planning process so that their high-standard implementation can be assured.

Sustainability analysis of the Munessa- Shashemene dry Afromontane natural forest from local communities’ perspectives

ABSTRACT Assessing attitudes and perceptions of local communities is a crucial step in forest management and planning that can have major consequences for sustainability. However, empirical studies on sustainability analysis from local communities’ perceptions are scarce especially on the Afromontane forests. Therefore, this paper analyzes the sustainability of Munessa-Shashemene dry Afromontane natural and plantation forests from local communities’ perceptions. The data were collected from randomly selected 200 households, five key informants, and six focused group discussions. The results revealed that the majority (85.5%) of respondents influenced the sustainability of the Munessa-Shashemene dry Afromontane natural forest based on the current forest product utilization trends and perceptions of the economically preferred tree species in the forest. The forest products have been decreasing over time due to deforestation and degradation of the Munessa-Shashemene forest (93.5%) and economically valuable tree species were substituted by inferior one for various forest products. Consequently, as an area with both general and particularly economically valuable indigenous tree species, the Munessa-Shashemene forest can be sustained by implementing intensive silvicultural operations and enrichment planting for economically favored tree species along with Hagenia abyssinica, Juniperus procera, and Myrsine melanophloeos. Further research investigations are needed on the restoration techniques of degraded preferred tree species to enhance sustainability and reduce future challenges related to forest degradation.

Mortality and Growth in a Sessile Oak [Quercus petraea (Matt.) Liebl.]-Dominated Young Stand Managed through Silvicultural Operations of Different Types and Intensities

A small-scale R&D project, including a block with four plots (P1-4) of 200 m2, was established in 2001 in a 15-year-old sessile oak-dominated stand, regenerated naturally through the application of group shelterwood cutting. In each plot, “potential” final crop trees were selected, based on vigour-quality-distribution criteria, and painted. Silvicultural interventions (cleaning-respacing and thinning), of different types and intensities were performed in P1-3 (P4 was kept as control) as well as P5 (500 m2), established in 2009, in 2001, 2004, and 2009. The mortality intensity between 2001 and 2019 was the highest in P4 and the lowest in P1, with the minimum stand density. Sessile oak showed the highest mortality, followed by Hungarian oak and Turkey oak. The fastest diameter growers were the “potential” final crop trees, their quadratic mean diameter (QMD) reaching values close to 20 cm at 35 (30-40) years in the plots with the lowest stand density. In all plots, trees have reached heights corresponding to the QMD of ca. 15 m, which are typical to a sessile oak stand of high productivity (production class II). The best solution for managing sessile oak young and medium-aged stands seems to be a “dynamic”, crop tree silviculture, with the most valuable individuals selected as “potential” final crop trees at the end of thicket stage. These trees should be favoured by subsequent heavy intensity thinning from above, in order to produce timber with as uniform as possible radial increments of 2-3 mm, as requested by veneer and high-quality saw log buyers.

Increased levels of forestry best management practices reduce sediment delivery from Middle and Lower Coastal Plain clearcut harvests and access features, southeastern states, USA

Over 390,000 ha of forestland are clearcut annually (1–2%) across the Coastal Plain region of the southeastern U.S. where forestland occupies approximately 30 million hectares in the region. Extensive periods of high-water tables, wet-weather and harvesting, rutting, erodible soils, and drainage networks typical of the Coastal Plain increase the potential for erosion and stream sedimentation. To mitigate these impacts, water quality forestry Best Management Practices (BMPs) were developed for erosion and sediment control and are recommended and approved by all southeastern state forestry agencies for application during and after harvests. The goal of this study was to estimate erosion and sedimentation from silvicultural operations in the Coastal Plain under three different and previously recognized levels of BMP implementation including BMP– (<80%), BMP-standard (80%–90%), and BMP+ (>90%), where 90% represents average implementation. A total of 35 recent clearcut sites were evaluated in the Coastal Plain of 12 southeastern states. Erosion was estimated via the USLE-Forest model at five operational features, including decks, stream crossings, haul roads, skid trails, and harvest areas only, which were classified into one of three BMP levels. Sediment traps were utilized on a subset of Coastal Plain sites in Virginia and North Carolina so that sediment delivery ratios (unitless) could be calculated. Clearcut area estimates were obtained from the United States Forest Service (USFS), Forest Inventory and Analysis (FIA) Program. The percent areas comprised within each operational feature were multiplied by total clearcut areas in the Coastal Plain region so that erosion and sedimentation estimates could be expanded to a regional scale. Examination of the different levels of BMP implementation revealed estimated sedimentation rates of 0.5 Mg ha−1 yr−1 and 0.4 Mg ha−1 yr−1 at the BMP-standard and BMP+ levels, respectively. The range of overall estimated sediment masses at the BMP-standard and BMP+ levels most accurately reflects the current state of BMP application in the Coastal Plain. BMPs were most obviously effective at mitigating erosion and potential sediment delivery from Coastal Plain skid trails and haul roads. The highest level of BMP implementation (BMP+) at forest roads and skid trails mitigated approximately 95% of sediment compared to BMP–. Overall sediment removal efficiencies were 77% for BMP-standard and 83% for BMP+ respectively when compared to BMP–. Conclusively, this study demonstrates that forestry BMPs are highly effective at mitigating erosion and stream sedimentation when appropriately applied in the southeastern Coastal Plain.

The impact of season on heart rate variability and workload of workers in young tree tending operations of a Larix kaempferi (Lamb.) Carr. stand: a preliminary study

ABSTRACT Larix kaempferi (Lamb.) Carr. plantations are a reasonable alternative to timber production for producing high-quality wood for South Korean industrial applications that need appropriate and high-quality practice of silvicultural operations. Weeding and tree pruning operations, which can favor trees in their competition with vegetation, require intensive manual labor. Therefore, the objective of this study was to determine the effect of these operations on the heart rate variability, relative heart rate (RHR), and physical workload of workers in April (spring) and July (summer) months. Our results showed that the mean heart rate variability and RHR for weeding (108.0 bpm and 49.4%, and 105.8 bpm and 46.8% for worker A and B, respectively) and tree pruning (104.5 bpm and 46.1%, and 114.4 bpm and 55.9% for worker A and B, respectively) in July were higher than those in April. In addition, the level of workload in July was characterized as heavy to very heavy, and as moderate to heavy in April. The results from this study provide useful information for appropriate young tree tending operations from the perspective of the safety and health of workers.

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The present study aimed to investigate the comparative growth performance and the eco-physiological response of tree species grown under intensive silvicultural management practices (Water management, drip fertigation, pruning, and thinning operations). The tree plantation was established in October, 2017 and maintained at Forest College and Research Institute, Mettupalayam, Coimbatore, India (11° 19’ N and 77°56’ E), with an altitude of 300 m above MSL and mean annual rainfall of 920.5 mm. The study was carried out with 3m x 2m in 7 different tree species namely Neolamarckia cadamba, Acrocarpus fraxinifolius, Grewia tiliaefolia, Melia dubia, Tectona grandis, Swietenia macrophylla, and Dalbergia sissoo. The biometric (Height and Diameter at Breast Height), biochemical (Chlorophyll) and physiological parameters (Photosynthesis rate and Transpiration rate) were measured at different ages under field conditions. The tree species namely Neolamarckia cadamba, Melia dubia, and Tectona grandis recorded the highest biometric observations, chlorophyll, photosynthesis rate, and transpiration rate. It is interesting to note that, even though Tectona grandis is a long rotation tree crop, the tree perform superior growth performance in early stages. Swietenia macrophylla showed poor performance in both the biometric and physiological parameters. The present study recommended that planting fast-growing tree species with short rotation can yield maximum biomasscompared to the long rotation trees if the tree plantation is appropriately managed with intensive silvicultural operations.

Rejuvenation of Reserve Forest by Forest Interventions (Species and Different Plantations)

Abstract: Eco-restoration is a technique for rejuvenation of degraded ecosystem to their near original state. It also helps to control soil erosion, develop microbial ecology, enhance biomass production and socio-economic development. The present study was focused on a new approach called Rejuvenation Technology for less forest area. India is bestowed with the rich diversity of flora and fauna due to diverse environment. Global warming and consequent impending danger of climate changes has necessitated to arrest deforestation. The species diversity has also helped in the selection of appropriate native species to enhance the ecological functions of urbanizing landscapes. Adoption of monoculture plantations though the region appears green, but fulfilling the vital ecosystem functions such as groundwater recharge, food and fodder to dependent biota, etc. Forest Rejuvenation Action Plan was prepared for each Reserve Forest Block with forestry activities like Reserve Forest boundary deep trench, fencing, Plantations of Gacchakaya on trench mounds along the periphery of the Reserve Forest boundary having interface with Revenue Land to protect the forest from biotic interference. Further Soil &amp; Moisture Conservation works were proposed to improve moisture regime. Silvicultural operations like Cultural operations &amp; removal of invasive species were proposed for better natural regeneration &amp; growth of existing root stock. It was further supplemented with plantations like Block plantations, fruit bearing plantations, Yadadri Model plantations, Grassland development in 0.0 - 0.10 canopy density forest area. Further plantation activities like Gap planting, Medicinal herbs &amp; Shurbs, plantation inside and on the mounds of SCT, Bamboo plantations along nalas/Streams were proposed to improve three tier canopy in the Reserve Forest in 0.1 - 0.40. These Forestry Interventions help to improve the forest cover, biodiversity, Carbon sequestration, Water Argumentation etc to meet the required results as per National &amp; Global Commitments. To demonstrate this technology, plantation of seedlings of 5 different canopy density. Block plantation. Yadadri Model Plantations, Grass lands, Forest Fruit bearing Plantations was carried out in a village community degraded land located in Medhal district in Telangana State. This study developed spatial definitions of the Rejuvenation of reserve forest. Keywords: Rejuvenation, Reserve forest, Plantation models, canopy, Soil &amp; Moisture Conservation

Combining Landscape Fire Simulations with Stand-Level Growth Simulations to Assist Landowners in Building Wildfire-Resilient Landscapes

The wildfire regime in Portugal has been responsible for millions of hectares of burnt area, and Alvares parish is no exception. In 2017, a severe wildfire burnt 60% of its area. Land abandonment has been increasing since the mid 20th century, and a large fraction of the forest area belongs to quasi-absent landowners. This has given rise to large, almost unbroken expanses of undermanaged forests that, in combination with rugged topography, originates a landscape prone to large, intense wildfires. Thus, a change in landscape composition and structure capable of reducing flammability and promoting fuel discontinuity is urgently needed. A fire spread simulator and a forest growth simulator were combined to show the impact of improving management at landscape level. It was assumed that the probability of large wildfires may be reduced by setting aside forest area for the implementation of a fuel break network (FBN) and increasing the area under sustainable forest management. Three levels of management intensity were simulated by restricting the area of Quasi-absent non-industrial owners to 34.5%, 20.1%, and 8.5% of the Alvares forest area, in favor of increasing the area of active and semi-active non-industrial owners (current, moderate, and high management scenarios). Different FBN extents, representing four levels of network implementation priority were combined with the management levels, resulting in 12 scenarios. To evaluate the impact of fire, simulations assuming no-fire, no-FBN, and current management intensity were performed, whereas the impact of operation costs was assessed assuming reduced costs for silvicultural operations. Per hectare simulations were then scaled up to the parish level and volume harvested and net present values were used to compare the management improvement scenarios. Results showed that fire has major repercussions on forest income, but these impacts can be minimized. Intensifying forest management and implementing the first priority FBN segments originated substantial improvements in financial outcome from timber production, close to those obtained for the full FBN implementation. Results also evidenced contrasting contributions from industrial and non-industrial owners with the later evidencing unbalanced cash-flows derailing the possibility for interesting forest incomes. The coupling of fire and forest growth simulations can be an interesting approach to assess the impact of different management and policy scenarios and inform policies.