Forest Science最新文献

{"title":"Site Index Models for Loblolly Pine Forests in the Southern United States Developed with Forest Inventory and Analysis Data","authors":"Mukti Ram Subedi, Dehai Zhao, Puneet Dwivedi, Bridgett E Costanzo, James A Martin","doi":"10.1093/forsci/fxad039","DOIUrl":"https://doi.org/10.1093/forsci/fxad039","url":null,"abstract":"Abstract Accurate productivity estimates are essential to assess the overall sustainability of forest resources. Site index (SI) models for loblolly pine (Pinus taeda L.) in plantation and natural forests of the southeastern United States were developed using the Forest Inventory and Analysis (FIA) database. We extracted short (~20 years), unbalanced panel data from the FIA database. Ten different nonlinear models derived from the base models using the algebraic difference approach (ADA) or the generalized algebraic difference approach (GADA) were fitted to the extracted data. The performance of the models was ranked based on a variety of fit and evaluation statistics. The results showed that all top three models were derived using the GADA approach. The best model for loblolly pine plantation and natural forest stands was derived from the Hossfeld model and the Chapman–Richards model, respectively. The best-fitted models for planted forests were also compared with previously developed models. This study demonstrated that base-age invariant and polymorphic SI models could be developed using short panel data extracted from FIA data. The SI models presented here can be used as a height growth model component in forest growth and yield model systems. Study Implications: Improved site index equations for assessing the site quality of loblolly pine plantation and natural stands are now available to stakeholders at the policy, management, and operational levels. Activities such as forest management, restoration, and wildlife management, which require site quality data, will benefit from the new models. Furthermore, the approach of deriving panel data based on Forest Inventory and Analysis data offers information on developing and updating models for other species. Finally, the approach of this study, to use permanent plot measurement data in developing growth and yield models, is cost-effective and time-efficient.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135734720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tree Mastication and Helimulching: Two Alternatives for Mitigating Soil Erosion and Carbon Loss After Wildfire","authors":"Cristina Fernández","doi":"10.1093/forsci/fxad041","DOIUrl":"https://doi.org/10.1093/forsci/fxad041","url":null,"abstract":"Abstract The use of masticated tree debris to protect burned soil from post-fire erosion is not common and very little is known about its effectiveness in reducing the risk of erosion after fire. The main objective of this research was to assess the effects of agricultural straw helimulching and tree mastication on soil and carbon losses and recovery of vegetation during 2 years after fire in two wildfire-affected areas in northwestern Spain. Eighteen plots were established in each experimental site for monitoring the following treatments: helimulching, mastication, and control (untreated burned soils). Salvage logging was carried out in the first spring after fire in one of the experimental areas, thus enabling study of whether the application of mulch after fire also protects the soil during logging. Mean soil cover in helimulched areas was more than 90% in both experimental sites, whereas masticated slash from juvenile pine trees covered around 60% of the burned soil. In both study sites, soil and carbon losses were significantly higher in the untreated soils than in the helimulched and masticated soils. Mulching was effective in reducing soil and carbon losses even after salvage logging. Study Implications: The use of mulches to protect burned soil from post-fire erosion is becoming common in fire-prone areas. Agricultural straw is the most common material, whereas other alternatives such as the use of masticated tree debris to reduce soil erosion risk after fire is not as common. The results obtained in this study show that mastication of noncommercial trees is a feasible technique to reduce post-fire soil erosion, although cover of more than 60% must be achieved to reduce soil erosion and carbon loss to sustainable values. Application of straw mulch is effective to protect burned soil during salvage logging.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135254679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends in United States Family Forest Owners’ Attitudes, Behaviors, and General Characteristics from 2006 to 2018","authors":"Emma M Sass, Brett J Butler, Jesse Caputo, Emily S Huff","doi":"10.1093/forsci/fxad040","DOIUrl":"https://doi.org/10.1093/forsci/fxad040","url":null,"abstract":"Abstract Family forest owners (FFOs) control a plurality of forestland in the United States, and the decisions these landowners make have a profound impact on the landscape. Most research on FFOs consists of cross-sectional studies, although many of these recognize the importance of capturing long-term trends to understand whether and how FFO attitudes, behaviors, and general characteristics are changing. We use data from the 2006, 2013, and 2018 iterations of the USDA Forest Service, National Woodland Owner Survey (NWOS), with a bootstrapping approach to identify significant changes across these time periods among FFOs with 4+ hectares of forestland. Total FFO hectares decreased and FFO ownerships trended downward over the study period. A decreasing proportion of FFOs owned farms or homes near their forestland, harvested timber, or received advice. Demographic shifts include an increase in age and education level from 2006 to 2018, and an increase in FFOs of color from 2006 to 2013. Overall, we find a trend towards decreased traditional engagement and management and a slight increase in owning land for its amenity values. Understanding temporal trends in FFO characteristics, attitudes, and behaviors will help policymakers and forestry professionals inform and update their outreach, technical support, and financial assistance programs. Study Implications: Families and individuals hold more forestland than any other ownership group in the United States. We use nationwide survey data from 2006, 2013, and 2018 to determine whether and how these landowners are changing over time. The total forestland held by FFOs decreased between 2006 and 2018, and there has been a decrease in traditional forest management and engagement, such as through timber harvesting and nearby farm ownership. This study provides insights for policies, programs, and outreach and a foundation for future long-term comparisons of this group.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135236161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Relative Importance of Crown Position and Vigor in Determining the Growth and Mortality of Sugar Maple Trees","authors":"Malcolm J L Cecil-Cockwell, John P Caspersen","doi":"10.1093/forsci/fxad038","DOIUrl":"https://doi.org/10.1093/forsci/fxad038","url":null,"abstract":"Abstract In northern hardwood forests, selection silviculture aims to remove low-vigor trees that are likely to die or grow slowly to increase the growth of the remaining high-vigor trees, particularly those afforded more exposure to direct light. However, few studies have quantified the relative importance of crown position and vigor in determining growth and mortality. In this article, we did so for the most common species, sugar maple (Acer saccharum Marsh.), and we quantified the difference in growth and mortality between each of four crown classes to determine whether fewer classes can be used to describe competition-related variation in growth. Our results show that mortality is primarily determined by vigor, competition reduces growth more than the defects used to assess vigor, and there is only a modest difference in growth between dominant and co-dominant trees, indicating that these two classes can be merged because they are effectively released, unlike trees that are surrounded by competitors. Based on these results, we conclude that stand improvement should not be prioritized over crown spacing, and that tree markers should release surrounded trees to whatever extent possible, including as many trees as possible and low-vigor trees where necessary.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136336396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrogen-Fixing Plants Enhance and Stabilize Rhizospheric Soil Organic Carbon in Tropical Rainforests, Hainan Island, China","authors":"Huai Yang, Shirong Liu, Jingxin Wang, J. Schuler, Yi Wang, Junwei Luan","doi":"10.1093/forsci/fxad037","DOIUrl":"https://doi.org/10.1093/forsci/fxad037","url":null,"abstract":"\u0000 Nitrogen (N)-fixing plants play an important role in stimulating soil nitrogen supply, but the effect of N-fixing plants on soil organic carbon (SOC) sequestration has not been well documented. In this study, we measured rhizospheric carbon components and N content of first to second (1–2)-order and third to fifth (3–5)-order roots of N-fixing and non-N-fixing plants in a montane tropical rainforest in Hainan Island, China, to examine the effects of N-fixing plants on SOC and soil heavy fraction carbon (HFC), and to ascertain the main regulating factors. The results showed that rhizospheric SOC between (1–2) and (3–5)-order roots was 14.2% and 10.5% greater, respectively, for N-fixing plants compared with non-N-fixing plants. Similarly, the HFC was 0.9% (1–2) and 3.6% (3–5) greater for N-fixing plants than non-N-fixing plants. Redundancy analysis showed that spatial variance in rhizospheric SOC and HFC associated with 1–2-order roots was explained by specific root length (SRL) of second-order roots (55.8%) and specific leaf area (SLA) (14.6%), whereas spatial variance was better explained for 3–5 roots by total soil N (44.6%), diameter of fifth-order roots (16.4%), and leaf C (17.9%), respectively. Within the rhizospheric soil of 1–2 roots, N-fixing plants with smaller SRL of second-order roots presented greater SOC and HFC, whereas smaller SLA was associated with greater HFC. By contrast, rhizospheric soil of 3–5 roots under N-fixing plants had greater SOC and HFC levels in environments with higher total soil N and smaller diameters of fifth-order roots. Our study revealed that N-fixing plants enhanced rhizospheric SOC and HFC compared with non-N-fixing plants. The rhizospheric SOC and HFC were correlated strongly by root morphology traits, leaf morphology, and soil properties.\u0000 Study Implications: In this article, we compared rhizospheric soil of N-fixing and non-N-fixing species in a montane tropical rainforest in Hainan Island, China, to examine the effects of N-fixing plants on SOC and HFC. Our results suggest the N-fixing plants enhance and stabilize rhizospheric SOC and HFC; rhizospheric SOC and HFC for first- to second-order roots of N-fixing plants were mostly negatively regulated by SRL of second-order roots; and N-fixing plants had positive effects on rhizospheric SOC and HFC for third- to fifth-order roots through increased soil N. Understanding these mechanisms could improve and accumulation of soil C sink in tropical areas.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"42 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81604707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can Moisture-Indicating Understory Plants Be Used to Predict Survivorship of Large Lodgepole Pine Trees During Severe Outbreaks of Mountain Pine Beetle?","authors":"Liam Easton, Trevor Goward","doi":"10.1093/forsci/fxad036","DOIUrl":"https://doi.org/10.1093/forsci/fxad036","url":null,"abstract":"Abstract Why do some mature lodgepole pines survive mountain pine beetle outbreaks while most are killed? Here we test the hypothesis that mature trees growing in sites with vascular plant indicators of high relative soil moisture are more likely to survive mountain pine beetle outbreaks than mature trees associated with indicators of lower relative soil moisture. Working in the Clearwater Valley of south central British Columbia, we inventoried understory plants growing near large-diameter and small-diameter survivors and nonsurvivors of a mountain pine beetle outbreak in the mid-2000s. When key understory species were ranked according to their accepted soil moisture indicator value, a significant positive correlation was found between survivorship in large-diameter pine and inferred relative high soil moisture status—a finding consistent with the well-documented importance of soil moisture in the mobilization of defense compounds in lodgepole pine. We suggest that indicators of soil moisture may be useful in predicting the survival of large pine trees in future pine beetle outbreaks.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135656304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wood Supply from Family Forests of the United States: Biophysical, Social, and Economic Factors","authors":"B. Butler, Emma M Sass","doi":"10.1093/forsci/fxad034","DOIUrl":"https://doi.org/10.1093/forsci/fxad034","url":null,"abstract":"\u0000 Wood products are an essential provisioning ecosystem service with US forests providing nearly one-fifth of global wood supply. As of 2018, an estimated 46% of the annual wood harvested came from corporate forests, 42% came from family forests, and the remainder came from other private, public, and Tribal forests. The supply of wood from corporate forests is well described by traditional economic models, but the supply from family forests is much less well understood. This article combines data from three components of the USDA Forest Service’s Forest Inventory and Analysis program—plots, landowner surveys, and mill surveys—with other data to model the wood supply from family forests in the United States. Results are summarized in terms of bivariate relationships and a logistic regression model. The model results show that basal area, stand origin, forest type, having timber as an ownership objective, the amount of annual income derived from their forestland, proximity to a mill, management advice, and region are significantly associated with family forest timber harvesting. The results should be useful for forest industry analysts and others interested in understanding the current and potential future supply of wood from family forests.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"49 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89841327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stem Profile Patterns of Pinus nigra and Pinus sylvestris Growing in Mixed Stands","authors":"R. Özçelik, K. Poudel, F. crecente-campo, Bora Kaya, Onur Alkan","doi":"10.1093/forsci/fxad035","DOIUrl":"https://doi.org/10.1093/forsci/fxad035","url":null,"abstract":"\u0000 Taper equations provide one of the most successful approaches of calculating tree volume to specified top diameters from standing tree measurements. This study assessed the stem profile patterns of Black pine (Pinus nigra Arnold.) and Scots pine (Pinus sylvestris L.) trees growing in mixed stands in northwestern Türkiye using a segmented polynomial taper equation. Models were fitted with the continuous second-order autoregressive structure to correct for the autocorrelation. The models fit the data well, describing more than 99%, 98%, and 97% of variation in diameter, merchantable volume, and total stem volume, respectively. However, the prediction errors were slightly larger for black pine than for Scots pine. Results also revealed that the model coefficients for these species were significantly different. Models developed in this study should provide more accurate upper stem diameter and volume estimates when the objective is to estimate such attributes for black pine and Scots pine growing in the mixed stands.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"56 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73104466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Use and Performance of Sealed Bid versus Oral Timber Auctions by State Forestry Agencies: A Minnesota Case Study","authors":"M. Kilgore","doi":"10.1093/forsci/fxad033","DOIUrl":"https://doi.org/10.1093/forsci/fxad033","url":null,"abstract":"\u0000 State governments are responsible for the stewardship and management of more than 28 million ha of forest land in the United States. This study presents the findings of an in-depth examination of the characteristics and performance of sealed bid and oral auctions using records from more than a thousand tracts offered for sale by the Minnesota Department of Natural Resources, which administers one of the nation’s most robust state timber sale programs. The study found that although tracts offered for sale through oral and sealed bid auctions sold at the same rate and are undifferentiated with respect to nearly all characteristics, sealed bid tracts generated significantly higher winning prices and additional revenue per hectare than tracts sold using oral auctions. Logging businesses were more likely to win sealed auctions than oral auctions, and their portfolio of purchased tracts contained a higher proportion acquired through sealed bid auctions than the portfolio of sealed bid tracts purchased by mills. The study adds to the limited body of literature on public agency timber auctions and is the first to provide a detailed analysis of the auction methods used by a state forest management agency.\u0000 Study Implications: Public agencies use sealed bid and oral auctions to sell timber rights. This study of the nation’s largest state timber sale program found that the auction method used affects winning bid prices, the likelihood certain categories of bidders will win the auction, the allocation of timber to mills and logging businesses, and revenue generated for each hectare of timber sold. State timber sale program administrators may be able to use these findings to better understand how the choice of auction method affects the financial performance of their timber sale program as well as the allocation of timber among the major types of bidders.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"580 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77013801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Partial Harvest Effects on the Forest Floor at Four Northern Hardwood Sites in the Green Mountains of Vermont, USA","authors":"D. Ross, M. E. Knowles","doi":"10.1093/forsci/fxad032","DOIUrl":"https://doi.org/10.1093/forsci/fxad032","url":null,"abstract":"\u0000 Harvesting activities are known to decrease forest floor carbon pools, but the response varies with harvest intensity. We examined partial harvesting (33–55% of basal area removed) effects on the forest floor at four northern hardwood sites in Vermont, USA. Six baseline quantitative samples were taken at each site and 9–36 new locations were sampled 1.5–2.6 years after harvesting. Forest soil disturbance was estimated, and basal area was tallied pre- and post-harvest. The forest floor consisted primarily of Oi and Oe horizons. The pre-harvest site means in carbon stock ranged from 6.8 to 12.3 Mg ha-1 and were not significantly different after harvesting. The pre-harvest site means in depth ranged from 2.8 to 4.5 cm and, post-harvest, there was significantly decreased thickness at one site and significantly greater density at two sites postharvest. This compaction was also visually observed in the field. Partial harvesting, which included single-tree and group selection, created highly variable conditions that challenged our experimental design. However, the two sites with the higher number of resampling locations (35–36) had relatively low variability in forest floor metrics and showed significant responses in thickness and density. Continued monitoring is needed to determine long-term trends.","PeriodicalId":12749,"journal":{"name":"Forest Science","volume":"37 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75700585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}