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Deadwood-dependent (saproxylic) insects represent a large proportion of forest biodiversity, are major contributors to ecosystem processes, and are conservation priorities due to their sensitivity to changing forest conditions. Despite relevance across much of the world, research on saproxylic biodiversity has been concentrated in Europe where interest was first generated. A major impediment for this field elsewhere is a lack of resources to determine which species are saproxylic. Here, we attempt to facilitate research on saproxylic beetles (Coleoptera) in the southeastern USA by compiling information from 18 published studies and theses in the region. A list of 1,393 taxa (species or genera) from 74 families is provided with deadwood associations. This includes 891 taxa from 71 families that were reared or emerged from deadwood, and 831 taxa from 61 families that were collected from bulk trapping methods and considered to be saproxylic, or were previously included in a list of regional deadwood taxa. Additionally, for 293 taxa from non-economically important families that were considered to be saproxylic in a recently published study, known saproxylic habits, microhabitat associations, and conservation notes are listed. Sixty-eight of these species represent new state records in Georgia, USA. Although a checklist of saproxylic species is needed for the southeastern USA, it is precluded by a dearth of knowledge about the natural history and distribution of species in the region. Increasing our understanding of these species’ habitat requirements is essential for understanding biodiversity responses to changing forest conditions and assessing conservation needs.

Currently, there is no consensus on how growing conditions affect the heartwood formation in Scots pine. Comparing the results obtained by different authors is difficult due to methodology differences and poor descriptions of the objects used. We selected two sample plots in (1) a blueberry pine forest on nutrient-rich and moist soil and (2) a lichen pine forest on nutrient-poor and dry soil and performed their detailed characterization. The sample plots were located 22 km apart in the middle taiga subzone (Karelia Republic, northwest Russia). In each sample plot, we selected five dominant trees (model trees), from which we took cores at different trunk heights (0.3, 1.5, 4.5, 7.5 and 10.5 m). The cores were treated with 2,6-dichlorophenolindophenol to identify the heartwood zone. Additionally, samples were taken to study the structural features of the transition zone between sapwood and heartwood. In both forest types, the number of heartwood rings depended on the cambium age, and the patterns of parenchyma cell death did not differ in the transition zone. These facts point to a predominantly internal regulation of the heartwood formation in Scots pine. The heartwood radius and its proportion on the cross-sections were significantly higher in the blueberry pine forest than in the lichen pine forest, despite the relative values of the annual ring width. Further research is needed to develop successful Scots pine heartwood width models under a wide range of conditions.

Macroecological studies have established widespread patterns of species diversity and abundance in ecosystems but have generally restricted their scope to relatively steady‐state systems. As a result, how macroecological metrics are expected to scale in ecosystems that experience natural disturbance regimes is unknown. We examine macroecological patterns in a fire‐dependent forest of Bishop pine (Pinus muricata). We target two different‐aged stands in a stand‐replacing fire regime: a mature stand with a diverse understory and with no history of major disturbance for at least 40 yr, and one disturbed by a stand‐replacing fire 17 yr prior to measurement. We compare properties of these stands with macroecological predictions from the Maximum Entropy Theory of Ecology (METE), an information entropy‐based theory that has proven highly successful in predicting macroecological metrics in multiple ecosystems and taxa. Ecological patterns in the mature stand more closely match METE predictions than do data from the more recently disturbed, mid‐seral stage stand. This suggests METE's predictions are more robust in late‐successional, slowly changing, or steady‐state systems than those in rapid flux with respect to species composition, abundances, and organisms’ sizes. Our findings highlight the need for a macroecological theory that incorporates natural disturbance, perturbations, and ecological dynamics into its predictive capabilities, because most natural systems are not in a steady state.

The purpose of this study was to examine the feasibility of using a river as a water source for purification of soil damaged by the tsunami in a pine forest in Enjugahama, Mihama town, Wakayama prefecture, and to create a “purification map” visualizing the amount of purification water. Soil from the pine forest was placed in a plastic container and seawater was poured into it, followed by river water. The amount of water required for soil purification was determined by measuring the EC at this time. It was confirmed that 333,364 m3 of water would be required to purify the entire pine forest, which is approximately 1 km2. The time required to collect this volume of water from the West River would be 265 h (about 2 weeks) for an average flow rate. These results were aggregated to create the purification map. Using this map, it is possible to estimate the amount of water needed for purification at any given point and to make decisions, such as prioritizing areas that are easier to purify, thereby contributing to the purification of pine forests after tsunamis. However, it could be said that purification would be difficult in cases where seabed sediments have been deposited on the soil.

The dynamics of forest ecosystems depend largely on the survival of seedlings in their understories, but seedling survival is known to be limited by preemption of light and soil resources by overstory trees. It has been hypothesized that \"common mycorrhizal networks,\" wherein roots of seedlings are linked to overstory trees by symbiotic mycorrhizal fungi, offset some or all of the negative effects of trees on seedlings. Here we report the results of an unambiguous experimental test of this hypothesis in a monodominant Pinus radiata forest. We also tested the hypothesis that adaptive differentiation among plant populations causes local plant genotypes to respond more positively to mycorrhizal networks than nonlocal plant genotypes. Our results demonstrate large positive effects of overstory mycorrhizal networks on seedling survival, along with simultaneous negative effects of tree roots, regardless of whether plant genotypes were locally derived. Physiological and leaf-chemistry measurements suggest that seedlings connected to common mycorrhizal networks benefited from increased access to soil water. The similar magnitude of the positive and negative overstory effects on seedlings and the ubiquity of mycorrhizal networks in forests suggest that mycorrhizal networks fundamentally influence the demographic and community dynamics of forest trees.

The Raráámuri (Tarahumara) people live in the mountains and canyons of the Sierra Madre Occidental of Chihuahua, Mexico. They base their subsistence on multiple-use strategies of their natural resources, including agriculture, pastoralism, and harvesting of native plants and wildlife. Pino Gordo is a Raráámuri settlement in a remote location where the forest has not been commercially logged. We reconstructed the forest fire regime from fire-scarred trees, measured the structure of the never-logged forest, and interviewed community members about fire use. Fire occurrence was consistent throughout the 19th and 20th centuries up to our fire scar collection in 2004. This is the least interrupted surface-fire regime reported to date in North America. Studies from other relict sites such as nature reserves in Mexico or the USA have all shown some recent alterations associated with industrialized society. At Pino Gordo, fires recurred frequently at the three study sites, with a composite mean fire interval of 1.9 years (all fires) to 7.6 years (fires scarring 25%% or more of samples). Per-sample fire intervals averaged 10-–14 years at the three sites. Approximately two-thirds of fires burned in the season of cambial dormancy, probably during the pre-monsoonal drought. Forests were dominated by pines and contained many large living trees and snags, in contrast to two nearby similar forests that have been logged. Community residents reported using fire for many purposes, consistent with previous literature on fire use by indigenous people. Pino Gordo is a valuable example of a continuing frequent-fire regime in a never-harvested forest. The Raráámuri people have actively conserved this forest through their traditional livelihood and management techniques, as opposed to logging the forest, and have also facilitated the fire regime by burning. The data contribute to a better understanding of the interactions of humans who live in pine forests and the fire regimes of these ecosystems, a topic that has been controversial and difficult to assess from historical or paleoecological evidence.

Lacking long‐term dendrochronological and lake sediment data, little is known regarding the history of fire in southern Appalachian forests through the Holocene. Here we used 82 radiocarbon ages for soil charcoal collected from local depositional sites along a topographic gradient from mixed hardwood (Liriodendron tulipifera and Quercus spp.) to oak–pine (Quercus prinus and Pinus rigida) forest to provide a coarse‐grained picture of changes in fire frequency within a 10‐ha area during the Holocene. Charcoal ages ranged from 0 to 10 570 yr BP, with a single date older than 4000 yr BP. The data indicate that fires occurred regularly across the study area over the past 4000 yr. Further, such fires were not confined to dry oak–pine dominated ridges, but extended downslope into areas that are today dominated by mesic hardwood forest. Summed probability analysis taking into account radiometric errors suggests that fires became more frequent ∼1000 yr ago, coinciding with the appearance of Woodland Tradition Native Americans in this region. We provide a direct demonstration of relatively frequent fire at the forest stand scale in Appalachian forests over a significant portion of the Holocene. Our results are consistent with the widely held view that fires have become less frequent in this region over the past 250 years. We discuss the difficulties in calculating the inbuilt error associated with estimating actual fire dates from charcoal fragments. But we conclude that such analysis of soil charcoal is a promising approach for reconstructing general trends in fire behavior within forest stands in this region.

Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pinedominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistenceoriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized sitespecific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

Pre-Euro-American settlement forest structure and fire regimes for Jeffrey pine-white fir, red fir-western white pine, and lodgepole pine forests in the Lake Tahoe Basin (California and Nevada, USA) were identified using stand structural analysis and fire scars based on measurements of stumps of trees that were cut in the 19th century. Comparisons of the presettlement reference with contemporary conditions were then used to determine how and why contemporary conditions deviate from presettlement conditions and to guide ecological restoration. Contemporary forests varied in different ways compared to the presettlement reference. Contemporary Jeffrey pine-white fir forests have more and smaller trees, more basal area, less structural variability, and trees with a more clumped spatial distribution than presettlement forests. The mean presettlement fire-return interval for Jeffrey pine-white fir forests was 11.4 yr, and most (>90%) fires burned in the dormant season; no fire was recorded in the study area after 1871. Similar differences were identified in the structural characteristics of contemporary and presettlement red fir-western white pine and lodgepole pine forests. However, 19th-century logging changed the composition of red fir-western white pine forests, and these forests now have more lodgepole pine than red fir or western white pine. Comparison of contemporary forests with the presettlement reference suggests that restoration treatments in Jeffrey pine-white fir forests should include: (1) density and basal-area reduction, primarily of smaller diameter trees; (2) reintroduction of frequent fire as a key regulating disturbance process; and (3) increasing structural heterogeneity by shifting clumped tree distributions to a more random pattern. Restoration treatments in red fir-western white pine forests should include: (1) a shift in species composition by a density and basal-area reduction of lodgepole pine; and (2) increasing structural heterogeneity by shifting tree distributions to a more random pattern. In lodgepole pine forests the restoration emphasis should be: (1) a density and basal-area reduction of small-diameter trees; and (2) an increase in structural heterogeneity that shifts tree spatial patterns from clumped to a more random distribution. Reintroduction of fire as a regulating process into high-elevation red fir-western white pine and lodgepole pine forests can be viewed as a longer-term restoration goal. The method for quantifying presettlement reference conditions from stumps complements, or is an alternative to, methods based on dendroecology or repeat photography.

Question: Do regional differences in latitude, and local factors of disturbance and distance from mature forest, influence dispersal syndromes, rate of accumulation of species and total richness in a recovering temperate, subtropical and tropical forest? Location: Temperate old-growth red pine forest, Canada; subtropical Araucaria Atlantic forest, southern Brazil; tropical Gallery forest, central Brazil. Methods: We used path analysis to determine causal relationships of regional (latitude) and local (disturbance intensity, distance of recovering site from forest) factors on percentage zoochory, exponent æ from species-area relationships and total richness. Results: Path results showed linear decreases in percentage zoochory, z and richness with increasing latitude. Disturbance and distance from mature forest each reduced richness by similar amounts; however responses of percentage zoochory and z were inconsistent between the two local factors. A second path model, using only the subtropical and tropical forest, greatly increased model significance, yielded insignificant regional effects and strengthened effects of local factors on the three richness responses. Important results from this path model were linear decreases of z (0.1) and percentage zoochory (10%) and a log-decrease of richness (five-fold) 100 m from the mature subtropical and tropical forest. Conclusions: Regional differences in latitude and local effects of dispersal limitation can influence forest richness as strongly as disturbance alone. Isolated, recovering subtropical and tropical forest fragments of southern and central Brazil may therefore be recovering at much slower rates than estimates made from those adjacent to mature forest stands.