Forest Age Structure Research Articles

UAV Inventory of the Last Remaining Dragon Tree Forest on Earth

The last remaining Dragon Tree Forest on Earth survives on a small plateau (Roqeb di Firmihin) in Socotra Island (Yemen). The Socotran Dragon’s Blood Tree (Dracaena cinnabari Balf. f.) is endemic to the Socotra Archipelago UNESCO World Heritage Site. Being a culturally important and endangered tree species, its conservation is a priority. Despite this, a complete inventory of the Firmihin Dracaena forest (14.9 km2) has never been attempted before. We applied the use of unmanned aerial vehicles (UAVs) for the first time in conserving the Socotran Dragon’s Blood Tree. A pair of UAVs (small drones) were used during field surveys in 2021 to spatially describe individual tree positions, tree density, mortality, and the forest age structure. Aerial images were processed into a single orthophoto image of high spatial resolution (8 cm/pixel) used for detailed analysis. We applied image-enhancement techniques, used object-based classification, and corrected every entry manually during the inventory process. In total 35,542 individual living trees and 2123 uprooted trees were inventoried. The mean age of the forest, based on crown age (derived from crown size) was estimated at an average of ca. 300 years (291.5 years) with some individuals older than 500 years. Our analysis reveals that the trajectory of recent cyclones and the average direction of fallen trees in Firmihin are correlated, suggesting that intensified winds (as a result of global warming) catalyze the decline of the overmature forest. Our study illustrates the use of UAVs in collecting crucial data for the conservation and threat assessment of endangered tree species in Socotra, and regular drone inventories could be applied (e.g., after future cyclone events or landslides) to better evaluate the status of these vulnerable island ecosystems.

Age structure and climate sensitivity of a high Andean relict forest of Polylepis rodolfo-vasquezii in central Peru

For a better understanding of forest ecology, tree-ring studies can provide information on climate sensitivity, tree growth patterns and population age structure that can inform about stand dynamics such as recruitment of new individuals, and other interspecific interactions related to competition and facilitation. Little is known about the ecology of the recently identified high Andean tree species Polylepis rodolfo-vasquezii. Here, we analyzed the relationship between tree size and age of two P. rodolfo-vasquezii forest stands located in the central Peruvian Andes at 11°S in latitude, and compared their growth patterns and climate sensitivity. We measured the height and diameter of each individual tree and collected tree core samples of living trees and cross sections of dead standing trees to generate two centennial tree-ring chronology at Toldopampa (1825–2015 CE) and at Pomamanta (1824–2014 CE) sites. The dendrochronological dates were evaluated by 14C analysis using the bomb-pulse methods analyzing a total of 9 calendar years that confirm the annual periodicity of this tree species. At the Toldopampa stand most trees ranged from 70 to 80 years old, with a 190-year old individual, being an older and better preserve forest than Pomamanta, with younger trees, probably because more human disturbances due to closer village proximity. No significant relationships were found between tree age and size in the oldest stand alerting that tree diameter should not be used as a metric for estimating tree ages as a general rule. The distinct growth patterns and the size-age relationship observed at the two forests may reflect distinct histories regarding human activities such as fire and logging. Nevertheless, both the Toldopampa and the Pomamanta tree-ring width chronologies exhibited common growth patterns and shared a similar positive response to temperature of the current growing season. Overall, our study confirmed the annual radial growth periodicity in P. rodofolfo-vasquezii trees using an independent method such as 14C analyses and a strong climate sensitivity of this tree species. These findings encourage the development of an extensive P. rodolfo-vasquezii tree-ring network for ecological and paleoclimate studies in the tropical Andes in South America.

气候变化情景下天宝岩国家级自然保护区森林景观演替长期动态模拟

PDF HTML阅读 XML下载 导出引用 引用提醒 气候变化情景下天宝岩国家级自然保护区森林景观演替长期动态模拟 DOI: 10.5846/stxb202202170376 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(31370624);福建农林大学林学高峰学科建设项目(72202200205);福建江夏学院科研人才培育项目(JXS2020008) Long-term dynamic simulation of forest landscape succession in Tianbaoyan National Nature Reserve under climate change scenarios Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:气候变化将会对森林树种结构、空间结构以及林龄结构等产生重大影响,准确预测森林景观演替对未来气候变化的响应,不仅能够为科学管理森林生态系统提供理论依据,而且对制定生物多样性保护与珍稀物种保护策略也具有重要意义。本文运用LANDIS Pro 7.0与LINKAGES模型,模拟天宝岩国家级自然保护区8个树种在2种不同气候变化情景(RCP4.5和RCP8.5)下未来300年的森林植被演替动态,分析森林景观格局变化特征及其对气候变化的响应。结果表明:毛竹、马尾松、猴头杜鹃、长苞铁杉以及杉木的潜在面积分布与景观格局指数对气候变化的响应较为显著。在气候变化情景下,各树种的景观分维度均介于1.03-1.08,保护区内各景观斑块相对简单规则。毛竹、猴头杜鹃和杉木聚集度下降趋势明显而斑块密度显著上升,长苞铁杉随演替进行面积逐渐减少而聚集度相对较高且斑块密度剧增,马尾松斑块密度缓慢增加而聚集度先降后升,随气候变化这些树种的景观完整度都遭到了不同程度的破坏,且在RCP8.5气候情景下景观破碎化更严重。而气候变化对阔叶林与柳杉的影响则较小,且阔叶林在演替期间斑块密度下降而聚集度稳中有增,潜在面积分布呈现出良好的发展势头。随气候变化,天宝岩自然保护区森林景观的演替最终将朝着"常绿阔叶林为主、针阔叶混交林为辅"的群落组成演变,保护区森林景观格局对气候变化的响应较为敏感。 Abstract:Climate change will have a significant impact on forest tree species structure, spatial structure and forest age structure. Accurately predicting the response of forest landscape succession to future climate change not only provides a theoretical basis for scientific management of forest ecosystems, but also plays an important role in formulating strategies for biodiversity conservation and rare species conservation. In this study, LANDIS Pro 7.0 and LINKAGES models were used to simulate forest landscape succession dynamics of eight tree species in Tianbaoyan National Nature Reserve under two different climate change scenarios (RCP4.5 and RCP8.5) over the next 300 years, so as to analyze the forest vegetation landscape pattern change characteristics and its response to climate change. The results showed that the potential area distribution and landscape pattern index of Phyllostachys hetericycla, Pinus massoniana, Rhododendron simiarum, Tsuga longibracteata, and Cunninghamia lanceolata had significant responses to climate change. Under the climate change scenario, the fractal dimension index of each species ranged from 1.03 to 1.08, indicating that each landscape patch in the reserve was relatively simple and regular. For Phyllostachys hetericycla, Rhododendron simiarum and Cunninghamia lanceolate, the contagion index decreased while the patch density increased significantly. For Tsuga longibracteata, the contagion index was relatively high and patch density increased with the gradual decrease of area during succession. For Pinus massoniana, patch density increased slowly while contagion index first decreased and then increased. These results indicated that landscape integrity of these species was damaged to varying degrees with climate change, and landscape fragmentation was more serious under RCP8.5 climate scenario. However, climate change had no significant effect on broad-leaved forest and Cryptomeria fortunei. And for broad-leaved forest, the patch density decreased during succession while the patch aggregation increased steadily, and the potential area distribution showed a good momentum of development. Therefore, with the change of climate, the forest landscape succession in Tianbaoyan Nature Reserve will eventually evolve towards the community composition of evergreen broad-leaved forest, supplemented by mixed coniferous broad-leaved forest. And the forest landscape pattern of the nature reserve is more sensitive to climate change. 参考文献 相似文献 引证文献

Fire severity and pre-fire forest composition affect Northern Hawk Owl presence in burned forests in western North America

Wildfire is an important natural disturbance shaping the boreal forests of North America. Not surprisingly, many species have adapted to benefit from the structural or functional changes in response to fire. Of these post-fire species, the Northern Hawk Owl (Surnia ulula caparoch) is one of the least studied species on the continent. We surveyed 18 recent fires in the boreal forest region of Alberta, Canada, ranging in age from 1 to 14 years post-fire, to improve our understanding of post-fire habitat relationships for this species. Hawk owls were present in fires ranging from 2 to 11 years post-fire, and occupied burns ranging in size from 1,000–272,000 ha. Hawk owls were strongly associated with areas of older deciduous-dominated forest, based on pre-fire forest inventory. Hawk owl responses to pre-fire forest age structure and composition were consistently stronger at the 1000 m radius (home range) extent than the 400 m (nest site) extent. We also found hawk owls responded differently to time since fire, with an immediate (e.g. 2–6 yr) response to low severity fire and a delayed (10–11 yr) response to high severity fire. We recommend future surveys for this species be conducted earlier in the day, ideally within a few hours of sunrise, based on the timing of detection in this study. Finally, the retention of large patches (e.g. > 300 ha) of older, deciduous-dominated habitat within post-fire forests may be an important management consideration for the conservation of hawk owls and other post-fire species.

Spatially explicit optimization of the forest management tradeoff between timber production and carbon sequestration

Forest farms are the main body of forest management at the landscape-scale in China, and have long sought ways to jointly maximize timber production and other ecosystem services. Carbon sequestration is of particular interest because China has established the goal of becoming carbon neutral by 2060. However, optimizing the balance between timber production and carbon sequestration is a challenge due to a lack of methods that account for the spatial arrangement of forest management activities within a landscape. This study developed a multi-objective planning model for forest management approaches to promote natural forest regeneration, adjusting the stand age structure of plantation forests to an even distribution across a landscape, and quantified the effects of social preferences and market prices on optimal management. The results show that depending on the dominant ecosystem services provided by the forests, forest management could promote an increased timber volume and stand carbon stock that is sustainable in the long-term. Social preferences have a relatively small influence on optimal management plans after forests are restructured to a normal forest age class distribution. In addition, forest management dynamics are more sensitive to carbon prices than timber prices. Hence, the spatial allocation of different management practices and forest restructuring, rather than protecting forests or managing them less intensively, is more effective for improving forest carbon stocks. More importantly, an urgent need also exists to increase the carbon price to guide and strengthen the attention of forest managers to forest carbon sequestration, with the goal of achieving a win–win strategy.

The European forest carbon budget under future climate conditions and current management practices

Abstract. To become carbon neutral by 2050, the European Union (EU27) net carbon sink from forests should increase from the current level of about −360 to −450 Mt CO2eq yr−1 by 2050. Reaching this target requires additional efforts, which should be informed by the expected interactions between current age-class distributions, the effect of forest management practices and the expected impacts of future climate change. However, modelling the combined effect of these drivers is challenging, since it requires a mechanistic assessment of climate impacts on primary productivity and heterotrophic respiration and a detailed representation of the forest age structure and of the management practices across the entire EU. To achieve this goal, we combined the output provided by four land–climate models – run under two different Representative Concentration Pathway scenarios (RCP2.6 and RCP6.0) – to parameterize the input data used in an empirical forest growth model. This hybrid modelling approach aims to quantify the impact of climate change and forest management on the long-term (i.e. to 2100) evolution of the EU27 + UK forest carbon budget. This approach was tested using a business-as-usual (BAU) scenario, based on the continuation of the management practices applied by EU member states within the historical period 2000–2015. We emphasize that our study does not explore a specific policy scenario but describes a methodological framework. Our results highlight that, under our BAU case, the EU27 + UK forest C sink would decrease to about −250 Mt CO2eq yr−1 in 2050 and −80 Mt CO2eq yr−1 by 2100. The main driver of the long-term evolution of the forest C sink is the ongoing ageing process of the European forests, mostly determined by past and ongoing management. In addition, climate change may further amplify or mitigate this trend. Due to the large uncertainty in climate projections, in 2050 the net C sink may range from −100 to −400 Mt CO2eq yr−1 under RCP2.6 and from −100 to −300 Mt CO2eq yr−1 under RCP6.0. These results suggest that while a change in management practices would be needed to reverse an otherwise declining trend in the sink, climate change adds a considerable uncertainty, potentially nearly doubling or halving the sink associated with management.

FORESTRY LAND USE OF THE BUSK FORESTRY ENTERPRISE: HISTORICAL AND GEOGRAPHICAL FEATURES AND CURRENT STATE

The research is devoted to the study of forestry land use in the zone of activity of the Busk forestry enterprise. A comprehensive geographical study of forests in the territory of Male Polissia as a whole and its individual parts is relevant both from an ecological and economic point of view. Its importance is growing in the context of the administrative reform and improvement of the land resources of the established communities and the consolidation of forestry enterprises announced in 2021. Today, Ukraine is not able to provide its own needs in timber and is one of the least forested countries in Europe. The territories of Male Polissia, including the newly formed Busk and Krasne and neighboring territorial communities, are promising for afforestation, in particular plantations.
 The authors of the article believe that it is possible to understand the modern structure of land resources only through the prism of history. For these reasons, the study used cartographic materials of different times, which made it possible to trace the development of several forests from the end of the 18th century to the present. The study was carried out on four time slices: the map by Friedrich von Mieg of the late 18th century, the topographic map of the Austro-Hungarian Empire at the end of the 19th century, the topographic map of the Military Geographical Institute of the 30s of the 20th century. and a modern satellite image of Google.
 The zone of activity of the Busk forestry enterprise fully covers the territory of the Busk and Krasne territorial communities and is partially located on the lands of the Dobrotvir, Novyi Yarychiv, Kamianka-Buzka, and Hlyniany communities. The forests of the studied region are part of nine forestries of Tadani, Hrabova, Verbliany, Polonychna, Kutkir, Ozhydiv, Sokolia, Neznaniv, Bolozhyniv. The largest areas are Tadani - 3917 hectares and Verbliany - 3603 hectares of forestry, and the smallest is Polonychna forestry, with an area of 1456 hectares. In the zone of activity of the study forestry enterprise, the forestry enterprise " Halsillis " also operates, uniting collective farm forests. The average forest cover of the study region is 20.9%. The highest forest coverage is observed in the north-west of the zone of activity of the Busk forestry enterprise.
 In the process of research, the authors developed statistical and stock materials of the forestry enterprise. On the basis of these data, maps of the species composition, age structure and timber stock in the context of forest areas were built and analyzed. The geospatial features of pine, black alder and oak stands have been revealed. Based on the processing of the cadastral map, promising areas for afforestation are proposed.
 As a result of the study, it was found that the characteristic features of forestry in the region are: uneven forest cover of the study area; significant fragmentation of the forest fund in the southern part of the forestry enterprise; location of large forest areas in the northwestern part of the forestry enterprise; dominance in stands of such species as pine, oak, alder; a slight increase in the forest cover of certain territories due to the creation of pine forest plantations on non-land areas and the active expansion of black alder forests on waterlogged pastures.
 Analysis and generalization of taxation materials made it possible to establish that the age structure of forests is dominated by medieval (44.7%) and plantations - 24.5%, young forests occupy 19.4%, and only 11.4% of the area covered by forests falls on mature ones and overgrown plantings. Such an age structure indicates intensive forest management on the territory of the forestry enterprise over the past decades and the active work of foresters on the formation of the species composition of forests.
 We have studied the division of the forest fund into categories. It has been established that the largest area of the forest fund of the Busk forestry enterprise is occupied by operational forests - 22202.1 hectares (87.8%). Protective forests account for 1.5% of the total forest area of the study region. The share of recreational forests in the structure of the forest fund is 9.5%. The forest supply of the population in the Krasne united territorial community averages 0.12 hectares/person, in Busk are 0.61 hectares/person.
 The total stock of wood in the forestry enterprise is 4576.36 thousand m³. In the structure of reserves, 52.7% is occupied by conifers. Hardwood and softwood species each account for 23.7% of the wood reserves of the study region. In geospatial terms, the distribution of wood reserves is extremely uneven and correlates with forest areas.
 Keywords: forest; wooded area; forestry enterprise; forest categories; forest tract; species composition; age structure of the forest.

Uncovering forest dynamics using historical forest inventory data and Landsat time series

While many countries regularly produce timely and accurate estimates for a range of forest attributes through national forest inventory programs, many have access to no such inventory or their inventory is discontinuous in space and time, such as a sample-based approach in Ukraine limited to two regional (Ivano-Frankivsk and Sumy) inventories conducted in 2008–2015 at a total area of 37,700 ha. This study addresses the extent to which limited historical forest inventory data may facilitate forest mapping efforts using dense Landsat time series (LTS) and mapping techniques (i.e., classification and imputation) to predict multiyear forest dynamics. We used the Continuous Change Detection and Classification (CCDC) segmentation approach to extract inter- and intra-annual trends in LTS and utilized these fitted trends as covariates in further modeling. We developed random forest (RF) classification models for forest mapping based on field data collection and LTS, and then generated yearly forest maps for 1990–2020. The RF model accuracies were high for both producer’s and user’s accuracy (>0.93 ± 0.04). Based on yearly forest dynamics, we detected an increasing trend in forest loss during 2000–2010 and 2010–2020 in our regions. We used the gradient nearest neighbor (GNN) method to generate species presence (basal area (BA) ≥ 1.0 m2 ha−1) and growing stock volume (GSV) maps at the 30-m pixel level. Our nearest neighbor imputation models achieved better accuracies (Cohen’s kappa > 0.4) for species that are prevalent within regions, occupy distinct geographical areas, and have higher plot BA abundance. To obtain estimates of species abundance with higher R2, we used the GNN model with k = 3 nearest neighbors. Aggregating species based on similar environmental niche resulted in greater R2 values of BA that varied within two regions from low (0.129 and 0.416) for a group of hardwood deciduous species to high (0.531 and 0.712) for coniferous species. The accuracy was systematically better at 5-km hexagonal level, thus we recommend using the maps at coarser aggregations. The study showed that forests accumulated more GSV in 1990–2000, albeit higher rates of GSV loss were observed during the two last decades. We attribute the spatial and temporal character of forest change to forestry activities in the past, the current age structure of forests, and afforestation of abandoned farmlands. We are aware that forecasting performance of the nearest neighbor imputation approach merits more detailed consideration as new forest inventory data are available.

Potential for carbon sequestration and the actual forest structure: the case of Krasnodar Krai in Russia

Abstract This work aims to analyze the age structure of forests in Krasnodar Krai in order to estimate their carbon sequestration potential. The research was conducted during 2015–2020 in 14 forested districts of Krasnodar Krai in the Russian Federation. A database of 96,000 sample plots was used. Aspen occupied the maximum area (20% of trees), while much smaller areas were occupied by linden, birch, pine, and oak (p≥0.05 with aspen). Spruce occupied three times smaller areas compared to aspen (p≤0.05), while maple, elm, ash, and alder had ten times smaller areas (p≤0.01). Among deciduous species by age, mature and overmature stands predominate, while in conifers a young growth prevails (44% – for pines). All pine forests belong to the 1st quality class (91%), for birch and aspen, it is 75–80% of trees (p≤0.05 with the frequency for pine), for spruce – 52% (p≤0.05), and for oak – 10% (p≤0.01). Different tree species make different contributions to carbon sequestration – from 0.3 tons per 1 ha (Alnus glutinosa) to 1.7 tons per ha (Fraxinus excelsior). Taking into account the areas occupied in the forest by different tree species, their contribution will also be different – from 0.5 thousand tons/1 year (F. excelsior) to 290 thousand tons per 1 year (Populus tremula). The total increase in wood stocks and carbon sequestration is mainly due to six forest tree species. The results obtained can be used to assess the potential for carbon sequestration in temperate forests, taking into account their different age structure and tree species composition.

Composition, Age-Structure and Dendroecology of High Altitude Treeline Forest in the Western Himalaya, India

Composition, Age-Structure and Dendroecology of High Altitude Treeline Forest in the Western Himalaya, India

СОВРЕМЕННАЯ ДИНАМИКА ЛЕСОПОЛЬЗОВАНИЯ В БОРЕАЛЬНЫХ ЛЕСАХ РОССИИ (НА ПРИМЕРЕ АРХАНГЕЛЬСКОЙ ОБЛАСТИ)

The article examines the dynamics of forest management in the Arkhangelsk region for the period from 2008 to 2020. Over the past three years, about 44 million m3 of marketable timber has been cut (57.6% of the permissible harvest). The withdrawal of marketable timber (within the allowable cut) increased by almost 1.5 times (from 10.24 to 14.86 million m3). The maximum volume of harvested wood falls on 2018 and 2020, respectively. The share of soft-leaved wood cut down during the period under review increased from 19.1% to 31.1%. This increase is due to the transport accessibility of secondary deciduous plantations located in close proximity to logging roads. The average share of marketable timber harvested by non-clear felling was 14.4%, the maximum volume of timber harvested by these fellings was recorded in 2020 - 2.6 million m3 or 17.4%. The total area involved in economic activities increased by 38.5%, from 100.8 thousand hectares to 138.9 thousand hectares. On average, 22.6% was allotted for partial cutting, and 77.4% for clear cutting. Spatial analysis of partial cuttings in the total volume of timber harvesting showed a very low percentage (up to 10%) in 14 forestries. This is due to the logging of the last century, the structure of the forest fund, the presence of wet and swampy areas, the lack of road infrastructure, etc. The distribution of forestries by the intensity of forest use showed that a high intensity of harvesting of marketable timber (over 500.1 thousand m3) is observed in 13 forest districts, mainly concentrated in the south of the Arkhangelsk region. The dynamics of the forest fund testifies that modern forest management has made adjustments to the distribution of the areas of forest plantations in the context of age groups and household sections. For example, the area of coniferous forests decreased by 649.2 thousand hectares (3.8%), while the area of soft-leaved forests increased by 471.95 thousand hectares or 9.1%. Past and modern forest management is reflected in the age structure of forests. A very small percentage of ripening stands in the future will not make it possible to compensate for the felled ripe and overmature stands at their expense. It is possible to level the age structure of the forest fund and form a so-called continuous forest taking into account the current trends in forest management, when on average about 60% of periodic yield is cut down

AN ECOLOGICAL ASSESSMENT OF THE STATE OF SMALL RIVERS IN THE MIDDLE TAIGA SUBZONE OF KARELIA

A multidisciplinary survey of three small rivers emptying to Lake Onego was carried out; information was collected regarding the aquatic biota, the species and age structure of riparian forests, their floristic diversity, and soils. The integral indicator chosen to assess the ecological condition of the watercourses was the characteristics of the rivers’ fish fauna, in particular fish of the Salmonidae family. Surveys of the rivers and riparian forest communities yielded records of 181 vascular plant species (11 of them macrophytes), 11 moss species, 2 lichen species; the fish fauna was made up of 9 species. Overall, the riparian forests featured a relatively wide range of typological diversity. The tree stands varied from the poor Ledum types (site class V) to the most productive Oxalis types (site classes III–I). Analysis of the tree species and age structure of forests in the riparian buffers revealed a prevalence of stable coniferous tree stands in good condition. Statistically reliable correlations were detected between the fish fauna and the tree species composition and inventory characteristics of the riparian forest stands, soil morphological characteristics, and the species diversity of the living ground cover and macrophytes. The species diversity of the riparian and the aquatic biotas were found to correlate positively with each other. Fish numbers were seen to negatively correlate with some characteristics of riparian forest soils (forest floor thickness, podzolic horizon), while the correlation with the humus horizon thickness was positive. Significant positive correlations were identified between aquatic organisms (fish, zoobenthos) and a majority of the stream’s hydrological parameters. The resultant up-to-date information about water-forest system components is important for understanding the role of small streams, which, alongside the scant officially recognized “spawning” rivers, are an ecological niche in the life cycle of salmonid fishes in Northwest Russia.

PECULIARITIES OF FORESTS AND FOREST USE ON THE TERRITORY OF SOE «TERNOPIL FORESTRY»

The analytical investigation of forests (age structure, age-class composition, forest categories) and forest use on the territory of SOE “Ternopil forestry” has been made. It has also been defined that within the activities of Ternopil forestry the differences in age structure of forest ranges, kinds of compositions and functional types of forests have been noticed.
 SOE “Ternopil forestry” is located in the central part of Ternopil oblast, which is characterized by a low level of forest cover: Zbarazh region – 9.1%, Pidvolochysk region – 5.1%, Terebovlia region – 8.4%, Ternopil region – 7.9%, Zboriv region – 11%.
 The area of SOE “Ternopil forestry” is 26015.0 ha; including territory covered with forests – 23913.2 ha (91.9%). The enterprise is also composed of 8 forest divisions such as Mykulyntsi, Skalat, Terebovlia, Ternopil, Mshanets, Zbarazh, Zaliztsi and Budaniv divisions.
 The fraction of area covered with forest vegetation on the territory of SOE “Ternopil forestry” is between about 91.3 % in Skalat forest division up to 96.1% in Ternopil forest division. The parts which are not covered with vegetation are represented by seed plots, artificial forests, open forests, burned areas, timber blockings, meadows, biomeadows, forest paths, glades and others. The forest plantations dominate in the structure of total area of the forest fund (57.3%); they occupy the area of 14606.0 ha and forest seed plots – 36.4%.
 The largest area in forestry is taken up by recreation forests (12.7 thousand ha). They have the largest part among the other forest categories (48.6%). The smallest part is taken up by the forests, which carry nature conservation, scientific and history and culture mission.
 Exploitable forests are represented on the territory of Budaniv forestry and occupy the area of 3142.9 ha. Besides that, we have to note that the part of forests in all divisions has special way of using and can be exploited.
 In the age structure of forests the major part is taken up by middle-aged plantations (64.6%). The largest part of the latest is in Mshanets division – 71.5% and Ternopil division – 67.4%. The biggest part of young plantations is in Zaliztsi division – 21.1% and Mykulyntsi division – 18.3%.
 They take the largest area in Terebovlia forestry (3668.3 ha). There is a sufficient part of recreation forests in the majority of forestry and its amount fluctuates between 83.8% up to 98.1%. The smallest part of recreation forests is in Budaniv (1.8%) and Zaliztsi (9.5%) divisions.
 The dominating type of landscape in recreational forests is closed type – 89.3% of the area, half open – 6.4% and open – 4.3%.
 The average age of forest plantations in SOE “Ternopil forestry” is 61 years. The oldest are European Beeches – 80 years, European Oak – 65 years, Scots pine – 56 years, English field maple – 60 years.
 The main forest forming species are hard wooden broadleaved species which make up 86.4%. They take up the largest part in Skalat (93.6%) and Mykulyntsi (94.4%) forest divisions. Among the broadleaved species the European Oak is dominating, and takes up the area of 13270.7 ha. More than 50% of the area where conifers grow are taken up by the Scots Pine.
 One of the ways of forest use on the SOE “Ternopil forstry” territory is stocking up wood from logging of the main use and also logging of formation and recreation. The renewable logging is done in all the forest categories. The annual amount of such logging comes to 2.3 thousand m3. Besides the logging of main use there others – formation and hygienic of forests, care logging (enlightening, selective cutting, thinning) sanitation and forest renewals. The main amount of wood is logged from the main use on the area of 66 ha and amounts to 20189 m3
 It has been defined that the main ways of the forest use are logging and recreational forest use.
 Key words: forests, forest use, age structure, forest categories, recreational forests

Bat responses to silviculture treatments: Activity over 13 years of regeneration

Using silviculture treatments as a tool to create habitat for wildlife is a common practice in wildlife conservation and natural resource management. Although diverse forest age structures and composition benefit many wildlife species, relatively little is known about bat response to young forest habitat. Understanding how the activity of bats changes as young forests age, and the influence of landscape level, stand level, and biologically relevant variables on bat activity, can improve effectiveness of forest management actions designed to benefit bat populations. We measured activity of bats in young forests regenerating from harvests implemented 2007–2018. We selected 26 sites, each of which consisted of a regenerating stand and paired control stand in adjacent interior forest, and used acoustic monitors to record bat activity from 5 May – 9 September 2019 and 2020, with a break from 1 July – 14 July so that monitoring fell into pre- or post-volant timeframes. We used an information theoretic approach to assess support for landscape level, stand level, and biologically relevant variables on bat activity in regenerating stands. Through our research we found (i) bats were more active in young forest stands than natural canopy gaps in interior forests, (ii) bat activity was highest in the first few years post treatment and decreased as young forests continued to age, and (iii) bat activity was highly dependent on biological factors, not landscape or stand level factors. Collectively, these findings suggest that forest management for young forest habitat may benefit forest-associated bats, at least in predominantly forested landscapes where young forest habitat is under-represented.

The legacy of forest disturbance on stream ecosystem functioning

Abstract Forest clearance is a pervasive disturbance worldwide, but many of its impacts are regarded as transient, diminishing in intensity as forest recovers. However, forests can take decades to centuries to recover after severe disturbances, and temporal lags in recovery of ecosystem properties for different forest habitats are mostly unknown. This includes forest streams, where most studies of the impacts of forest clearance are restricted to the first years of recovery, typically finding that temporary increases in light and nutrient run‐off diminish as forest recovers. Implications of longer term changes remain little investigated. In a space‐for‐time substitution experiment, we assessed changes in organic matter processing and in the functional and taxonomic composition of litter‐consuming detritivores along a riparian forest age gradient ranging from 1 to 120 years since last timber harvesting. Variation in organic matter processing and detritivore functional diversity along the forest succession gradient were both expressed as second‐order polynomial relationships (peaking at ~50 years along the forest age gradient). Decomposition rates were lowest in both the more recently clear‐cut and older riparian forest streams. Variation of litter decomposition rates among litter bags within streams, measured by the coefficient of variation, was lowest in recent clear‐cuts and increased linearly along the succession gradient. This result indicates higher within‐stream heterogeneity in decomposition rates in older forest streams. Synthesis and applications. We found that the decomposition of leaf litter, a component of carbon cycling in forests, was higher in streams flowing through intermediately aged forest, and that several key attributes of the organisms regulating litter decomposition also varied systematically with forest age. These findings highlight the longer term consequences of forest succession following forest clear‐cutting for stream habitats. Our findings further illustrate complications arising from the use of forested sites as references for newly cleared sites without properly accounting for forest age, given conclusions regarding biotic responses will depend on the age of the reference forests. Finally, our results emphasise the potential of intensive forest management centred on vast, one‐time clear‐cutting events to drive long‐term homogenisation not only in forest age structure but also in the functioning of associated forest stream habitats. ​.

Biophysical climate impact of forests with different age classes in mid- and high-latitude North America

Forest age structures have been reported to be substantially influenced by natural and anthropogenic disturbances worldwide. However, related biophysical feedback to climate is not well understood. This study aims to investigate the biophysical impact of changes in forest age on surface temperature and illustrate the mechanisms underlying such temperature differences. To this end, we use data from five paired evergreen needleleaf forest (ENF) eddy covariance towers in North America. Results show that older ENF is 1.7 K cooler than younger ENF at annual scale. The latent and sensible heat fluxes of older forests dominate an average cooling effect of −1.9 K, which counteracts albedo-driven warming (+2.3 K). Additional warming effect is further offset by emissivity (−1.1 K) and incoming radiation (−0.5 K). Our results confirm that considering forest age may facilitate improved forest management to local climate mitigation and adaptation in future climate change.

Region-wide characterization of structural diversity of the U.S. Outer Coastal Plain Mixed Forests Province

Forest structural diversity is related to stability, biodiversity, adaptability and resilience, as well as productivity of forest ecosystems. In this study, we characterized structural diversity of the diverse forest type groups in the southeastern Outer Coastal Plains Mixed Forest Province of the United States. We utilized data from 13,658 Forest Inventory and Analysis (FIA) plots across the region and classified them on the basis of forest type group (i.e., longleaf-slash pine, loblolly-shortleaf pine, oak-pine, oak-hickory, oak-gum-cypress, or other), disturbance type (disturbed by animal, fire, insect and disease, weather, other disturbances, or no disturbance), ownership (public or private and Native American), site condition (xeric, mesic, or hydric), stand origin (natural or planted), and age structure (one or two age classes). The structural diversity was estimated as Shannon index of tree size diversity. Our findings indicate a range of 0.00 to 2.40 for Shannon index values across the forest type groups and the ecoregion. All forest attributes (i.e., forest type groups, disturbance type, ownership, site condition, stand origin, and age structure) significantly affected structural diversity at α = 0.05. Oak-gum-cypress was structurally the most diverse forest type group. Overall, plots that were publicly owned, naturally regenerated, two-aged, and affected by weather disturbances exhibited higher structural diversity. We also created region-wide structural diversity distribution and hot spot maps. The maps identified southern Mississippi, northern and eastern Virginia, northern North Carolina, eastern South Carolina, and the border between the states of Texas and Louisiana as the structural diversity hot spots. The middle part of Outer Coastal Plain consisting of southcentral Georgia, northcentral Florida, and southwest Alabama exhibited the lowest structural diversity.

The impact of land-use legacies and recent management on natural disturbance susceptibility in mountain forests

Mountain forests provide a wide range of ecosystem services, including carbon sequestration and protection from natural hazards. Forest cover in the European Alps has increased over the last century, but in recent years, these forests have experienced an increasing rate of natural disturbances by agents such as windthrow, bark beetle outbreaks, and forest fires. These disturbances pose a challenge for forest management, making it important to understand how site and stand characteristics, land use legacies and recent management influence disturbance probability. We combined a dataset of forest disturbances detected from space with in-situ forest management records, allowing us to differentiate between different types of disturbances for the Canton of Graubünden, Switzerland, in the years 2005–2018. The resulting dataset of over 28′000 attributed disturbance patches (corresponding to a disturbed forest area of ca. 23′600 ha) was combined with information on topography, forest structure, and historical forest cover. A machine-learning approach was used to investigate the non-linear and interacting relationships between potential drivers and disturbance occurrence. Natural disturbances (especially windthrow and bark beetle outbreaks) were most common at lower elevations, on shallow and south-facing slopes, and in even-aged, spruce-dominated stands with a closed canopy. Forests established in the 20th century were significantly more susceptible to natural disturbances than forests that were already present before 1880, which may be due to the uniform age and vertical structure of secondary forests, as well as legacy effects of former agricultural use. On the other hand, forest management more often took place in forests present before 1880. Management interventions (such as thinning) in turn increased the susceptibility to natural disturbances in the short term. This finding emphasizes the need to balance short-term increases in disturbance susceptibility with long-term benefits in forest resilience when planning management interventions in mountain forests. Our findings highlight the importance of considering multiple interactive drivers, including management and land-use history, for understanding forest disturbance regimes.

Лесной кодекс о лесопользовании в защитных лесах

The description of the organization of forest exploitation in the fundamental law acts existing the last 40 years is analyzed. The role and age structure of the protective forests are briefly characterized. Need of active management for maintenance of functionality of the protective forests is formulated. The important role of forest code for development of regulatory documents and effective implementation of the concept of ecosystem services is shown.

Carbon sequestration in living biomass of Slovak forests: recent trends and future projection

Abstract The paper predicts development of forests in Slovakia from the perspective of carbon sequestration. Projection is based on actual trends of changes in forest area, age structure and tree species composition of forest stands managed according to forest management plans. Carbon balance in living biomass has been simulated until 2050 under two harvesting scenarios (based on planned and realized harvesting rates in reference period 2014–2019) with four possible combinations of fixed or changing tree species composition and size of forest area. Input data were stratified by tree species and 10-years wide age classes. A model simulating forest growth using yield tables and harvesting rates was developed and applied for prediction. Results indicate that the scenario based on realized harvesting would lead to a higher level of CO2 removals from atmosphere by living biomass in Slovak forests for the whole simulated period, despite their decrease from the current level ~ −4,000 kt CO2 to ~ −2,000 until 2040 and an increase to~ −2,800 kt CO2 in 2050. Conversely, scenario based on planned harvesting could result in a stronger decrease of CO2 removals, with the culmination in 2040 at ~ −200 kt CO2 followed by a slight increase to ~ −1,000 kt CO2 in 2050. The influences of changes in tree species composition and increasing forest area were significantly lower than effect of different harvesting rates. Results achieved by this study suggest that adjusting harvested volume (e.g., by decreasing harvesting rates or modifying rotation periods) could be the most effective tool to intensify CO2 removals by living biomass in Slovak forests in the upcoming decades.