Knowledge and conservation of Old-Growth Forests: a key issue to face global changes. The case study of Strâmbu-Băiuț - Maramureş (Eastern Carpathians, Romania)

Old growth forests (OGF) represent ecological continuity and are rich in biodiversity. These unique landscapes are becoming increasingly rare in Canada, especially within the Acadian Forest Region that covers the Maritime Provinces. Less than 1% of the total forest cover in these provinces is OGF — this is drastically lower than the 55% represented in British Columbia’s Temperate Coastal Rainforest. The authors of this paper conducted a comprehensive comparative analysis of old forest policies and regulatory frameworks in Nova Scotia, New Brunswick and British Columbia to offer recommendations for improving the conservation and stewardship of OGF in the Maritimes. The analysis revealed that in Nova Scotia there is a strong old forest policy underpinned by a quantitative scoresheet, coordinator, and database. In New Brunswick and Nova Scotia the conservation targets are up to 8% on Crown land, but neither have a regulatory framework nor have evidence of achieving these targets. British Columbia has integrated Forest Stewardship Plans that promote the retention of OGF as legally enforceable tools for licensees in Old Growth Forest Management Areas. Such an approach could prove useful in improving the restoration and conservation of OGF in the Maritime Provinces.

Part 1 Patterns and determinants of climate and landscape change: scenarios of global warming, Stephen H. Schneider evaluating landscape change - patterns of worldwide deforestation and local fragmentation, Martha J. Groom and Nathan Schumaker population and community processes in the response of terrestrial ecosystems to global change, David S. Schimel. Part 2 Physiology and population responses to environmental change: terrestrial vegetation and climate change - integrating models and experiments, Stephen W. Pacala and George C. Hurtt plant defense, herbivory, and climate change, Matthew P. Ayres population responses to environmental change - operative environments, physiologically structured models, and population dynamics, Arthur E. Dunham climate change and ecological interactions, Anthony R. Ives and George Gilchrist individual-based models for predicting effects of global change, William W. Murdoch. Part 3 Evolutionary responses to environmental change: evolutionary genetics and climatic change - will animals adapt to global warming?, Ary A. Hoffmann and Mark W. Blows evolutionary responses of plants to global change, Monica A. Gever and Todd E. Dawson the evolutionary dynamics of fragmented plant populations, Kent S. Holsinger genetic consequences of extinction and recolonization in fragmented habitats, David E. McCauley evolution and extinction in response to environmental change, Michael Lynch and Russell Lande global change - lessons from and for evolutionary biology, Joseph Travis and Douglas J. Futuyma. Part 4 Community responses to environmental change: species dynamics and global environmental change - a perspective from ecosystem experiments, Stephen R. Carpenter, et al effects of global climate change on North American birds and their communities, Terry L. Root implications of climate change for stream communities, Nancy B. Grimm paleoecological perspectives on modeling broad-scale responses to global change, James S. Clark carbon dioxide limitation and potential direct effects of its accumulation on plant communities, David Tilman a salty and salutary perspective on global change, Robert T. Paine forecasting ecological responses to global change - the need for large-scale comparative studies, Michael L. Pace. Part 5 Landscape change and habitat fragmentation: species invasions and deletions - community effects and responses to climate and habitat change, David M. Lodge species diversity, spatial scale, and global change, Susan Harrison effects of global change on the dynamics of insect host-parasitoid interactions, M.P. Hassell, et al conservation planning for species occupying fragmented landscapes - the case of the Northern Spotted Owl, Kevin McKelvey, et al part contents.

The protection and conservation of old-growth forests (OGFs) are becoming a global concern due to their irreplaceability and high biodiversity. Nonetheless, there has been little research into the identification and characterization of OGFs of the oldest tree species in Mediterranean areas. We used forest inventory data, low-density airborne laser scanning (ALS) metrics, and geostatistical analysis to estimate old-growth indices (OGIs) as indicators of old-growth forest conditions. We selected a pilot area in European black pine (Pinus nigra subsp. salzmannii) ecosystems where the oldest known living trees in the Iberian Peninsula are found. A total of 756 inventory plots were established to characterize standard live tree and stand attributes. We estimated several structural attributes that discriminate old growth from younger age classes and calculated different types of OGI for each plot. The best OGI was based on mean tree diameter, standard deviation of tree diameter, and stand density of large trees (diameter > 50 cm). This index is useful for assessing old-growthness at different successional stages (young and OGFs) in Mediterranean black pine forests. Our results confirm that the estimation of OGIs based on a combination of forest inventory data, geostatistical analysis, and ALS is useful for identifying OGFs.

<p>Forestry is a regionally dominant land use but the carbon and climate impact of boreal forest management is not well characterized, partly because no large-scale maps of managed and primary unmanaged forests exist. Northern land has greened considerably during the last decades and there is evidence of the growing dominance of the boreal biome in the global land sink of carbon. However it remains unclear what drives the observed changes, if it is management or environmental changes.</p><p>In this project we have mapped and classified the naturalness of more than 400 primary forests in Sweden. The primary forests are found from the temperate south to the boreal north of the country, and managed secondary forests are identified close to each primary forest forming spatial pairs of primary and secondary forests that share climate and landscape history but not management. The primary forests represent a natural baseline of ecosystem states and changes. Changes in these forests are driven by regional to global environmental change such as elevated CO2 concentrations, warming or nitrogen deposition. The managed forests on the other hand are influenced by both environmental changes and management. By studying the states and changes in the primary forests we can gain new knowledge in how ecosystems would have changed and what their states would have been with no management. By contrasting changes and states in the managed ecosystems we can estimate the long-term influence of management on both states and changes.</p><p>In this project the maps are used in combination with more than 100k forest inventory plots, extensive targeted field sampling over two years and remote sensing to understand, (i) changes in remotely sensed greening since 1984, and (ii) differences in carbon storage. We will present and discuss preliminary and more mature results that suggests that (i) primary forests have greened considerably since 1984, and at mature ages, faster than managed forests do, and (ii) store considerably more carbon than the paired managed forests do. </p>

Old-growth forests are both rare and special ecosystems across most of the world. Policies to protect and possibly enhance and increase them are plentiful and diverse across nations and sub-national jurisdictions. Nova Scotia has had a policy on conservation of old-growth forests on public lands in the province since 1999. The second such policy dated 2012 was recently replaced by a revised policy in 2022. After presenting knowledge based on selected scientific literature about old-growth forests in Nova Scotia, the paper describes the improvements made in the 2022 policy. These include: (a) a more-nuanced set of operational definitions; (b) a commitment to protect all old-growth forest on public lands, whether currently identified or not; (c) robust replacement provisions in the rare event that the provincial government chooses to allow provincially significant infrastructure to be built on public land supporting old-growth forest; and (d) a renewed commitment to work with private landowners on their aspirations to conserve old-growth forest. The new policy, adopted in August 2022, also contains a commitment to a public review and possible renewal by August 2027.

The United Nations (UN) Framework Convention on Climate Change (UNFCCC), the Convention on Biological Diversity (CBD), and the UN Forum on Forests (UNFF) are the most important international environmental agreements to include forests. Old-growth forests are not an official forest category in these agreements, thus there is no direct support for the conservation of old-growth forests in international policy, nor is there a globally accepted international forest policy. Nevertheless, negotiations under UN conventions include mechanisms that could indirectly support the conservation of old-growth forests in the future. Under the UNFCCC, a new mechanism for reducing emissions from deforestation and forest degradation in the tropics could help conserve forests with high carbon stocks. A global network of forest protected areas is being discussed under the CBD. However, old-growth forests will be conserved only when international environmental agreements are implemented by individual countries through national and local action.

Conservation efforts for Blakiston's fish owl Bubo blakistoni in Russia are limited, partly because habitat use by these rare owls is poorly known. We therefore studied nesting and foraging habitat characteristics of Blakiston's fish owls in Primorye, Russia. We sampled habitat at 14 nest sites, 12 nest stand sites and 13 random sites; we also sampled rivers within 14 fish owl home ranges across our 20,213 km2 study area. We found that large old trees and riparian old-growth forest were the primary characteristics of nest and foraging sites, respectively. Large trees were probably used as nest sites because they have cavities large enough to accommodate these birds. Big trees are also important because they are primary sources of large woody debris in rivers, which enhances suitable habitat for salmon, the owl's primary prey. Based on habitat characteristics, nest sites were correctly distinguished from random sites 74% (Kappa = 0.48) of the time, nest stands from random sites 56% (Kappa = 0.12) of the time, and used sites from available foraging sites 68% (Kappa = 0.36) of the time. The management and conservation of old-growth forests is essential for sustaining this species because they are central to the owls' nesting and foraging behaviour. Moreover, conservation of these forests sustains habitat for many other species.

Climate change has a number of observed, anticipated, or possible consequences on crop health worldwide. Global change, on the other hand, incorporates a number of drivers of change, including global population increase, natural resource evolution, and supply demand shifts in markets, from local to global. Global and climate changes interact in their effects on global ecosystems. Identifying and quantifying the impacts of global and climate changes on plant diseases is complex. A number of nonlinear relationships, such as the injury (epidemic) damage (crop loss) relationship, are superimposed on the interplay among the three summits of the disease triangle (host, pathogen, environment). Work on a range of pathosystems involving rice, peanut, wheat, and coffee has shown the direct linkage and feedback between production situations and crop health. Global and climate changes influence the effects of system components on crop health. The combined effects of global and climate changes on diseases vary from one pathosystem to another within the tetrahedron framework (humans, pathogens, crops, environment) where human beings, from individual farmers to consumers to entire societies, interact with hosts, pathogens, and the environment. This article highlights international phytopathological research addressing the effects of global and climate changes on plant diseases in a range of crops and pathosystems.

Forests cover 30% of the terrestrial Earth surface and are a major component of the global carbon (C) cycle. Humans have doubled the amount of global reactive nitrogen (N), increasing deposition of N onto forests worldwide. However, other global changes—especially climate change and elevated atmospheric carbon dioxide concentrations—are increasing demand for N, the element limiting primary productivity in temperate forests, which could be reducing N availability. To determine the long-term, integrated effects of global changes on forest N cycling, we measured stable N isotopes in wood, a proxy for N supply relative to demand, on large spatial and temporal scales across the continental U.S.A. Here, we show that forest N availability has generally declined across much of the U.S. since at least 1850 C.E. with cool, wet forests demonstrating the greatest declines. Across sites, recent trajectories of N availability were independent of recent atmospheric N deposition rates, implying a minor role for modern N deposition on the trajectory of N status of North American forests. Our results demonstrate that current trends of global changes are likely to be consistent with forest oligotrophication into the foreseeable future, further constraining forest C fixation and potentially storage.

The hyperdiverse wood-inhabiting fungi play a crucial role in the global carbon cycle, but often are threatened by deadwood removal, particularly in temperate forests dominated by European beech (Fagus sylvatica) and Oriental beech (Fagus orientalis). To study the impact of abiotic drivers, deadwood factors, forest management and biogeographical patterns in forests of both beech species on fungal composition and diversity, we collected 215 deadwood-drilling samples in 18 forests from France to Armenia and identified fungi by meta-barcoding. In our analyses, we distinguished the patterns driven by rare, common, and dominant species using Hill numbers. Despite a broad overlap in species, the fungal composition with focus on rare species was determined by Fagus species, deadwood type, deadwood diameter, precipitation, temperature, and management status in decreasing order. Shifting the focus on common and dominant species, only Fagus species, both climate variables and deadwood type remained. The richness of species within the deadwood objects increased significantly only with decay stage. Gamma diversity in European beech forests was higher than in Oriental beech forests. We revealed the highest gamma diversity for old-growth forests of European beech when focusing on dominant species. Our results implicate that deadwood retention efforts, focusing on dominant fungi species, critical for the decay process, should be distributed across precipitation and temperature gradients and both Fagus species. Strategies focusing on rare species should additionally focus on different diameters and on the conservation of old-growth forests.

Ecological and social factors shaped old-growth forests of the western United States before Euro-American settlement, and will, in large part, determine their future. In this article, we focus on the social factors that affected the forest's ecological structure and function, review the changing cultural influences through law and policy of public land management and use, and discuss the changing public perceptions of fire use. We also provide an overview of the current debates about the conservation of old-growth forests, and the current congressional protection and management of old-growth forests in public land management and use.

The recent alterations in forests growth could be the result of a combination of different climatic and non-climatic factors, as rising atmospheric [CO2], temperature fluctuations, atmospheric nitrogen deposition and drought stress. This study tests the potential effects of global change on trees, assessing the relative importance and functional relationships between environmental drivers and long-term growth trend, as well as physiological response. To investigate such effects, we applied Generalized additive models (GAMs) technique, decoupling the non-linear age related effect from co-occurring environmental effects on basal area increments (BAI) series and isotope proxies (δ13C and δ18O). Two Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) chronosequence were considered; the first one, comprises four different age classes (age 65-, 80-, 95- and 120-) and is a even-aged stands plantation located in Italy, while the second one is an old-growth Californian stand, with three age classes (age 100, 200, 300). Results show a 22.9% decrease of the general BAI growth trend over last decades for the Italian Douglas-fir chronosequence, when the age-size non-linear effect was removed. A related trend in water use efficiency (iWUE=Amax/gs, the ratio between photosynthetic assimilation and stomatal conductance) was observed in the same period. Thus, through the application of the so called dual isotope approach, was possible to attribute to a reduction in Amax the cause of such a trend, probably driven by a reduction in N deposition. On other hand, BAI trend accounted for the Californian old-growth stand shows an increase of roughly the 60% since the 1960, which was found to be mostly determinate by a strong effect of atmospheric [CO2]. These founding highlight how this species has been affected by global change impact in both sits and provide important insights on its future behavior, potentially driving management choices.

Value-added forest management planning: A new perspective on old-growth forest conservation in the fire-prone boreal landscape of Canada

Little is known about the relevance of natural forests and plantations in the wake of global warming and climate change. Understanding the impacts of land use conversion from natural forests to plantations on carbon sequestration and storage is critical for sustainable land and forest management. In this study, tree-based carbon sequestration and storage abilities were assessed in natural and plantation forest ecosystems. Four plots within a natural forest and cashew orchard were randomly chosen and four belt transects were established. In each plot, tree species were identified and their density, height, Diameter at Breast Height (DBH) enumerated and measured, respectively. In each plot, litter boxes were placed to collect litter weekly. Soils (at 0 -15 cm and 15 – 30 cm) within each plot were obtained with soil auger. AGB (aboveground biomass), BGB (belowground biomass), AGC (aboveground carbon) and BGC (belowground carbon) were calculated using allometric equations for pan moist and dry tropical forest. Twenty-three and eleven tree species were found in the forest and orchard, respectively. The forest had the largest total biomass allocation (188.61 Mg ha-1) and carbon stock (146.89 Mg C.ha-1) while the orchard had the least total biomass apportionment (37.20 Mg ha-1) and carbon stock (45.60 Mg ha-1). The forest ecosystem had the largest sequestration ability (593.04 Mg CO2ha-1) which followed this trend: aboveground (295.18 Mg CO2ha-1) > belowground (60.51 Mg CO2ha-1) > soils (133.73 Mg CO2ha-1) > litter (49.62 Mg CO2ha-1) while cashew orchard had the least sequestration ability (167.37 Mg CO2ha-1) which followed this order: soil (99.09 Mg CO2ha-1) > litter (35.75 Mg CO2ha-1) > aboveground (27.00 Mg CO2ha-1) > belowground (5.53 Mg CO2ha-1). From these results, land use change affects carbon budgets of ecosystems, hence, this study argues for protection of natural forest while practicing afforestation towards global warming mitigation.

Ecosystem management is a conservation strategy, but there is not a standard protocol for implementation. In theory, ecosystem management will utilize the best available science to sustain social-ecological systems in the landscape by maximizing multiple ecosystem services expected from the stakeholders’ of those systems. Llancahue is a watershed (1,270 ha) that provides fresh water to the city of Valdivia (130,000 inhabitants) and protects >700 ha of old-growth forest within a severely disturbed landscape in the lowlands of south-central Chile. The native vegetation of this landscape is the threatened Valdivian Temperate Rainforests. Management of the watershed by the Universidad Austral de Chile needs to both provide timber and work to the neighboring campesinos (small poor rural land owners) who were illegally logging the forest and improve the conservation of the old-growth forests and the quantity and quality of water provided by the watershed. This paper demonstrates how adaptive management has utilized a multi-step process to improve management of the watershed. This process has included (1) understanding stakeholders’ views towards the project, (2) developing an ecosystem management plan for the watershed that balanced multiple societal demands and ecosystem functions from the watershed, and (3) monitoring the Llancahue forest and streams to ensure activities provided desired results. This paper reports results after 4 years of implementation and provides perspectives on the ecosystem management approach.