Clearcut Treatments Research Articles

Short-term effect of the harvesting method on ecosystem carbon budget in hemiboreal Scots pine forest: Shelterwood cutting versus clear-cut

Shelterwood cutting (SC) has been highlighted as an alternative method to clear-cut (CC)-based even-aged forest management. However, compared to CC, the effect of SC on stand carbon (C) balance is still poorly understood at the ecosystem level. We examined the prompt effect of SC versus CC on ecosystem net primary production (NEP) on a short-term scale, using the C budgeting method combined with eddy covariance (EC) measurements in hemiboreal mature Scots pine stands.The early effect of SC on annual C budget after removing 30–40 % of the growing stock revealed diverse patterns in the studied stands; NEP varied from 0.62 to −1.3 t C ha−1 yr−1 for the C sink and the C source, respectively. However, C loss decreased already in the second post-thinning year and levelled out attaining −0.41 t C ha−1 yr−1, which is close to balance.Furthermore, C loss declined in the second post-harvesting year at the CC sites as a result of the increased production of the ground vegetation and the decreased soil heterotrophic respiration (Rh) flux. However, C loss from dry mesotrophic clear-cuts was almost −1.8 t C ha−1 yr−1 for both study sites. Since estimation of the individual C fluxes for C budgeting is associated with variability-induced errors, the estimated values of NEP contain uncertainties of various levels.The estimated annual cumulative Rh flux was significantly higher in the SC versus CC areas and the mean annual Rh values across the study sites were 3.57 ± 0.25 and 2.59 ± 0.09 t C ha−1 yr−1, respectively.Annual estimated NEE after SC was 1.8 ± 0.52 t C ha−1 yr−1, gross primary ecosystem production was 9.28 ± 0.97 and total ecosystem respiration was 7.47± 0.28 t C ha−1 yr−1. The discrepancy between the estimated values of NEE and NEP was 1.2 t C ha−1 yr−1.In the short term SC demonstrated some advantage over CC from the perspective of the C cycle, but the difference in NEP values between the SC and CC treatments was not convincingly overwhelming. Hence, SC allows to maintain the forest cover for a longer period and to avoid drastic changes in the landscape; still, after SC, C budget varied between the C sink and the C source.

Spatially-explicit effects of small-scale clear-cutting on soil fungal communities in Pinus sylvestris stands

Clear-cutting is a common silvicultural practice. Although temporal changes in the soil fungal community after clear-cutting have been widely investigated, little is known about stand-level variations in the spatial distribution of soil fungi, particularly at the clear-cut edge. We performed spatial soil sampling in three clear-cuts (0.5 ha), edge habitats, and surrounding forests 8 years after clear-cutting to examine the impact of clear-cutting on the soil fungal community (diversity, composition, guilds, and biomass) and soil properties in a managed Pinus sylvestris forest in northern Spain. Our analyses showed small differences in the composition of the soil fungal community between edge, forest, and clear-cut zones, with <4 % of the species strictly associated with one or two zones. The richness, diversity, and evenness of the fungal community in the edge zone was not significantly different to that in the forest or clear-cut zones, although the clear-cut core had approximately a third fewer ectomycorrhizal species than the edge or the forest. Saprotrophic fungi were widespread across the clear-cut–forest gradient. Soil fungal biomass varied significantly between zones, ranging from 4 to 5 mg g−1 dry soil in the forest and at the forest edge to 1.7 mg g−1 dry soil in the clear-cut area. Soil organic matter, pH, nitrogen, and phosphorus did not differ significantly between edge, forest, and clear-cutting zones and were not significantly related to the fungal community composition. Overall, our study showed that small-scale clear-cut treatments are optimal to guarantee, in the medium-term, soil fungal communities within harvested areas and at the forest edge that are comparable to soil fungal communities in the forest, even though the amount of fungal biomass in the clear-cut zone is lower than at the forest edge or in the forest.

NATURAL REGENERATION DYNAMICS IN CAATINGA TREE SUBMITTED TO FOREST MANAGEMENT

This study aimed to evaluate the natural regeneration dynamics in Caatinga subjected to different forest management practices. The work was carried out in the Contendas do Sincorá National Forest, with the predominant vegetation cover being forested steppe savanna. The study area consisted of fixed plots plotted in 2015. The treatments were: control (Con); clear cutting (CC); selective cutting by minimum diameter at breast height ≥ 5 cm; and selective cutting by species. The phytosociological parameters were estimated for each species. The Shannon-Weaver Diversity Index and the Floristic Expansion Index (FEI) were calculated and the Ward method was used for the floristic similarity analysis. A total of 453 individuals were sampled, distributed in 31 species and five morpho-species. Combretum monetaria was highlighted in all treatments and phytosociological parameters. The similarity dendrogram shows that there is floristic similarity between the years 2015 and 2020. The CC treatment obtained the most species with positive FEI in the period from 2015 to 2017, with a result similar to the other treatments in 2020. It is concluded that there was no statistical difference between treatments in relation to diversity after five years of intervention. Stump regrowth was very important at the beginning of regeneration. The floristic similarity between 2015 and 2020 shows a recovery five years after the experiment installation. Management practices did not have a negative impact on the floristic richness of natural regeneration, demonstrating that the area recovers well even with the interference made in the area. Keywords : Steppe savanna, Floristic Expansion Index, Phytosociology.

Assessing the Effectiveness of Silvicultural Treatments on Fire Behavior in the Hyrcanian Temperate Forests of Northern Iran.

We implemented a fire modeling approach to evaluate the effectiveness of silvicultural treatments in reducing potential losses to the Hyrcanian temperate forests of northern Iran, in the Siahkal National Forest (57,110 ha). We compared the effectiveness of selection cutting, low thinning, crown thinning, and clear-cutting treatments implemented during the last ten years (n = 241, 9500-ha) on simulated stand-scale and landscape-scale fire behavior. First, we built a set of fuel models for the different treatment prescriptions. We then modeled 10,000 fires at the 30-m resolution, assuming low, moderate, high, very high, and extreme weather scenarios and human-caused ignition patterns. Finally, we implemented a One-way ANOVA test to analyze stand-level and landscape-scale modeling output differences between treated and untreated conditions. The results showed a significant reduction of stand-level fire hazard, where the average conditional flame length and crown fire probability was reduced by about 12 and 22%, respectively. The conifer plantation patches presented the most significant reduction in the crown fire probability (>35%). On the other hand, we found a minor increase in the overall burn probability and fire size at the landscape scale. Stochastic fire modeling captured the complex interactions among terrain, vegetation, ignition locations, and weather conditions in the study area. Our findings highlight fuel treatment efficacy for moderating potential fire risk and restoring fuel profiles in fire-sensitive temperate forests of northern Iran, where the growing persistent droughts and fuel buildup can lead to extreme fires in the near future.

Een leidraad in de conservatieve aanpak van de primaire frozen shoulder

A guideline in the approach of primary frozen shoulder The primary frozen shoulder is a frequent inflammatory condition, characterised by 3 main clinical stages: the painful, stiff and recovery phase. Each of them comes with a certain degree of irritability for the patient. Given the wide range of conservative therapy options, a clear-cut treatment is currently not available. There is sufficient evidence for the use of the following combined approach: the use of intra-articular corticosteroid infiltrations at first, followed by stretching and mobilization according to the Maitland technique in a later phase, along with patient education as well as a physiotherapy home programme. Crucial for this approach is to take into account the specific stage of the condition and the corresponding degree of irritability of the patient at that moment.

КЛИНИЧЕСКИЕ ХАРАКТЕРИСТИКИ НОВОЙ КОРОНАВИРУСНОЙ ИНФЕКЦИИ У ДЕТЕЙ

Currently it is about impossible to discuss whether children and adolescents carry the infectious process caused by the SARS-CoV-2 virus only in a mild and asymptomatic form. Ambiguous conclusions can be drawn from the reviewed publications of a number of recent studies in which children and adolescents with complicated course of the new coronavirus infection were under observation. More and more relevant are reports from scientists around the Globe about somatic symptoms that persist after the new coronavirus infection. The purpose of the study was to summarize and analyze the widely available data on the clinical features of the new coronavirus infection in children and adolescents in Russia and worldwide. The bibliographical research was carried out in the reviewed periodicals’ databases as follows: PubMed®, ScienceDirect, Cochrane Library, Google Scholar, eLIBRARY, and CyberLeninka. The keywords for the search were as follows: COVID-19, children, clinical features, clinical symptoms, post COVID syndrome, long-term symptoms after SARS-CoV-2, physical and mental health, new coronavirus infection, clinical manifestations, cognitive impairment. The reviewed period of publications screened: 2020 to 2022 (to date). In total 152 sources were analyzed, from which 60 most representative studies were selected, that in its turn provide data on the clinical features of SARS-CoV-2 in children during different periods of the disease, starting with the onset of the disease in different age groups. Children are as vulnerable to the SARS-CoV-2 infection as adults but more frequently suffer from the disease in mild forms. The main clinical manifestations during the acute period of COVID-19 in children are as follows: fever, respiratory symptoms (rhinorrhea, nasal congestion, cough, shortness of breath), gastrointestinal manifestations (nausea/vomiting, diarrhea), signs of sensory impairment (anosmia, ageusia), arthralgia/myalgia, weakness, fatigue. At the same time the new coronavirus infection can rapidly progress in a severe/life-threatening form in some children that would require intensive care and respiratory support. In addition, the aggravated comorbid background in the anamnesis of severe/critical cases has a significant value. The cardiological and neurological pathology has a special prognostic value as well. A number of publications have proven the indisputable fact of long-term COVID-19 symptoms in children. According to a number of studies more than 70% of those who recovered from COVID-19 complain of one or more symptoms after the end of the acute period of the disease; in some cases, these complaints can persist for up to 10 weeks, and even up to 6 to 7 months after the recovery (in a number of cases described). The prospect for the in-depth study of the course and consequences of COVID-19 in childhood will provide an opportunity to obtain a clear view on the most frequent clinical features of the disease, factors predisposing to the development of severe/critical/life-threatening conditions, and would allow to develop the clear-cut treatment and prevention algorithms.

Fruit Fly Larval Survival in Picked and Unpicked Tomato Fruit of Differing Ripeness and Associated Gene Expression Patterns.

Simple SummaryTephritid fruit flies are major pests to a wide range of fruits and vegetables. Female flies lay their eggs into the fruit where the resultant larvae cause damage and yield loss. To replace pesticide-based controls with more sustainable management approaches, we need to develop new generation technologies. Enhancing fruit resistance is a promising alternative but it has received limited research attention. In this study, we examined larval survival and gene expression changes of B. tryoni larvae and tomato fruit while the fruits were in different picking statuses (unpicked vs. picked) and ripening stages (colour break vs. fully ripe). We assessed larval survival in two time points of 48 h and 120 h after inoculation. The fruit picking status and ripening stage had a significant effect on B. tryoni larval survival at 120 h. The gene expression patterns were not affected by picking status; however, insect detoxification genes and plant-induced defence genes were upregulated across the treatments. Overall, we anticipated the lack of conformity between larval survival and gene expression as a result of overlooked candidate genes or critical sampling time points.The larvae of frugivorous tephritid fruit flies feed within fruit and are global pests of horticulture. With the reduced use of pesticides, alternative control methods are needed, of which fruit resistance is one. In the current study, we explicitly tested for phenotypic evidence of induced fruit defences by running concurrent larval survival experiments with fruit on or off the plant, assuming that defence induction would be stopped or reduced by fruit picking. This was accompanied by RT-qPCR analysis of fruit defence and insect detoxification gene expression. Our fruit treatments were picking status (unpicked vs. picked) and ripening stage (colour break vs. fully ripe), our fruit fly was the polyphagous Bactrocera tryoni, and larval survival was assessed through destructive fruit sampling at 48 and 120 h, respectively. The gene expression study targeted larval and fruit tissue samples collected at 48 h and 120 h from picked and unpicked colour-break fruit. At 120 h in colour-break fruit, larval survival was significantly higher in the picked versus unpicked fruit. The gene expression patterns in larval and plant tissue were not affected by picking status, but many putative plant defence and insect detoxification genes were upregulated across the treatments. The larval survival results strongly infer an induced defence mechanism in colour-break tomato fruit that is stronger/faster in unpicked fruits; however, the gene expression patterns failed to provide the same clear-cut treatment effect. The lack of conformity between these results could be related to expression changes in unsampled candidate genes, or due to critical changes in gene expression that occurred during the unsampled periods.

The retention of non-commercial hardwoods in mixed stands maintains higher avian biodiversity than clear-cutting

Abstract A diverse landscape can support a more diverse range of species and allow for more complex community structures. In forested habitats, openings and changes in tree composition allow for a higher species richness due to the greater chance of niche occupancy. Knowledge about these relationships may be useful for adapting forest harvesting strategies to, for example, support bird diversity conservation and studies are required to understand how different harvesting strategies influence forest structure and bird diversity. Here, we used Autonomous Recording Units (ARU) to record dawn signalling of forest birds between two forest-harvesting treatment types (complete clear-cuts and hardwood-retention patches) vs control forest patches in the John Prince Research Forest, British Columbia, Canada. We compared Species Richness and Shannon diversity as detected through identifying species in audio recordings, across treatments. The observed Species Richness and Shannon diversity did differ between the Retention treatment and Forest controls when controlling for number of individuals sampled, but both had higher Species Richness and Shannon diversity of passerine species than the Clear-cut treatments. When comparing species composition, we found that forest-associated species were disproportionately detected in Forest controls compared to Clear-cut treatments but detected at intermediate levels in Retention treatments. Species associated with early-seral habitats, though, had disproportionate detection in Clear-cut treatments compared to Forest controls, but also showed expected detections in Retention treatments. These results suggest that partial harvesting and retention of non-commercial hardwoods, can help retain forest-associated species while also helping attract early-seral avian species; this can help increase the overall diversity of the landscape while still making logging profitable. Further research should be conducted to determine the value of this retained habitat at different spatial scales to understand the impacts that it may have for larger-scale deployment.

Gallbladder carcinoma and extrahepatic cholangiocarcinoma

Gallbladder carcinoma and extrahepatic cholangiocarcinoma Abstract. In this article, we focus on three entities of malignant biliary tumors: gallbladder carcinoma, distal and perihilar cholangiocarcinoma. Those are rare malignant tumors which require an extensive interdisciplinary expertise in the treatment of hepato-pancreato-biliary conditions in order to provide an appropriate diagnostic work-up, correctly assess resectability and come up with a clear-cut multimodal treatment plan. Perihilar cholangiocarcinoma (Klatskin-tumour) usually requires the most complex evaluation of resectability, which involves not only the assessment of vascular in- and outflow and an adequate biliary drainage, but also aims to ensure that enough functional liver tissue is left after resection. To this end, preoperative portal vein embolization may be used to increase the size the future liver remnant. In highly selected, unresectable cases of perihilar cholangiocarinoma, or if a primary sclerosing cholangitis is present, neoadjuvant chemoradiotherapy followed by liver transplantation can be evaluated as a curative option. Distal cholangiocarcinomas usually are treated by a partial pancreaticoduodenectomy (Whipple operation). The surgical treatment of gallbladder cancer ranges from simple cholecystectomy to major liver resection with complex biliary and vascular reconstruction, dependent on tumour stage. The surgical treatment is usually followed by an adjuvant regimen of Capecitabine which can significantly improve survival, while a combination Cisplatin and Gemcitabine is used in the palliative setting.

Functional plasticity of carabids can presume better the changes in community composition than taxon-based descriptors.

Although the functional trait approach can facilitate the understanding of mechanisms that underline community responses to habitat alteration, only a few studies used this way on exploring the structure of insect assemblages compared to taxon-based analyses. We compared the descriptive power of medium-term effects (2014-2018) of forestry treatments in a temperate managed oak-dominated forest on taxon- vs. trait-based descriptors of ground beetle assemblages. The treatments included rotation forestry (partial preparation cutting, clear-cutting, retention-tree group, and mature closed forest as control) and continuous cover forestry (gap cutting) operations. The species composition was only slightly influenced by the treatments; on the ordination biplot, the control, retention tree group, and clear-cutting treatments formed relatively homogeneous groups, well separated from each other, while the others were scattered randomly in the ordination space. Over time, the species richness decreased in all treatments, but it was higher in the retention tree group treatment than in others in 2016 and 2017. The activity density also declined between years, but an immediate mass effect was revealed after the implementation of treatment types especially in the control, gap, and preparation cuts. We found that assemblages in the clear-cutting and retention-tree group had similar characteristics: high functional diversity; more open-habitat, generalist, and omnivore species and fewer carnivore species; while those in the control, gap, and preparation cutting groups had the opposite: lower functional diversity, more forest species, and more carnivorous species. Our findings will demonstrate that the simultaneous use of the two approaches will allow the most articulate understanding of the status of ground beetles assemblages in managed forests.

Effects of harvesting intensity, vegetation control and fertilization on 5–20 year post-harvest N availability in boreal jack pine and black spruce forest soils in northern Ontario, Canada

The impact of harvesting intensity, vegetation control and fertilization on soil N availability 5–20 years post-harvest was determined at 18 jack pine and black spruce forests in northern Ontario, Canada. The study sites are affiliated with the North American long-term soil productivity (LTSP) study. Boreal forest growth is commonly N limited and young stands approaching crown closure acquire most of their N from the soil. The study sites represented a range of soil types and were harvested with three levels of organic matter removal (stem-only harvest, full-tree harvest and full-tree harvest with organic horizon removal by blading). Three study sites had multiple applications of glyphosate to control competing vegetation and one site included a trial with two applications of N, P, K fertilizer to the full-tree harvest treatment. We used short-term anaerobic laboratory incubations and in-situ closed top tube growing season incubations to determine mineralizable N and net N mineralization, respectively. Profile (organic plus mineral horizons) mineralizable N pools were higher in operational clearcut (stem-only and full-tree harvesting) treatments compared to the uncut reference forest 10–14 years post harvest. Full-tree harvesting with blading significantly reduced profile mineralizable N pools at this time compared to operational harvesting, while the same treatment at one upland site also reduced net N mineralization pools. Profile mineralizable N pools and microbial biomass C and N were lower in full-tree compared to stem-only harvesting treatments, suggesting that increased slash retention with stem-only harvesting was playing a role in enhanced soil N availability at a time when plantations were approaching a period of greater N demand. Fertilization and vegetation control treatments had few effects on N indices, although net N mineralization pools for the stem-only and full-tree harvest that also had the repeated herbicide treatment were consistently, but not significantly, lower than non-herbicided treatments. Soil N indices were useful predictors of dominant height growth for jack pine to a greater degree than for black spruce, and soil N concentrations were as effective at predicting height growth as more resource intensive measurements. Our results point to the importance of continued monitoring of soil and stand conditions at these LTSP sites as treatment effects on soil N cycling and site productivity will likely continue to evolve. At this stage of stand development, full-tree harvesting plus organic horizon removal, followed by operational harvesting has led to lower soil N availability than operational tree-length harvesting, and stands with understory vegetation control are now showing indications of reduced N availability.

Aspects of transition cow metabolomics—Part I: Effects of a metaphylactic butaphosphan and cyanocobalamin treatment on the metabolome in liver, blood, and urine in cows with different liver metabotypes

Dairy cows in modern production systems are at risk to develop metabolic disorders during the transition period. Reasons for individual differences in susceptibility, as well as the underlying pathomechanisms, are still only partially understood. The development of metaphylactic treatment protocols is needed. In this context, an on-farm prospective 3-fold blinded randomized study involving 80 German Holstein cows was performed throughout 1 yr. The trial involved a thorough recording of the production and clinical traits, clinical chemistry, and liver biopsies and blood and urine sampling at d 14 (mean: 12 d, range: 1-26 d) antepartum (AP), and d 7 (7, 4-13) and 28 (28, 23-34) postpartum (PP) for metabolomics analyses. Two groups received a treatment with butaphosphan and cyanocobalamin (BCC) at either the dosage recommended by the manufacturer or the double dosage (5 or 10 mL/100 kg of body weight 10% butaphosphan and 0.005% cyanocobalamin (Catosal, Bayer Animal Health), n = 20 in each group, parity: 4.2 ± 2.0 and 3.4 ± 1.3, respectively (mean ± SD)] and one group a placebo treatment (NaCl 0.9%, n = 40, parity: 4.0 ± 1.9). The animals were treated at 6 time points (7, 6, and 5 d AP, and 1, 2, and 3 d PP) via intravenous injection. Mass spectroscopy-based targeted metabolomics analysis of blood plasma and liver samples were performed using the AbsoluteIDQ p180 kit (Biocrates Life Sciences), whereas the urine samples were analyzed by nuclear magnetic resonance spectroscopy. Statistical analysis was performed using multivariate [partial least squares discriminant analysis (PLS-DA)] and univariate methods (linear mixed model). Multivariate data analysis (PLS-DA plots) of the liver metabolome revealed 3 different metabotypes (A = medium, B = minor, C = large alterations in liver metabolome profile between AP and PP status). Metabotype B animals were characterized by higher PP lipomobilization (stronger PP body condition decrease and higher blood bilirubin, fatty acids, gamma-glutamyltransferase, and triglyceride levels) and a higher occurrence of transition cow diseases, compared with the animals in metabotype C. Analysis of the feeding data showed that the period of metabotype B animals (calving in a distinct time frame) was characterized by a decreased grass silage quality. The PP liver metabolome of the metabotype C animals was characterized by higher concentrations of AA, acylcarnitines, lysoPC and sphingomyelins compared with metabotype B. For the metaphylactic treatment with BCC a dose-dependent effect was confirmed, differing between the metabotypes. In all matrices and metabotypes at various time points significant treatment effects were observed, with different profiles in clinical chemistry and as well in metabolomics data. The most clear-cut treatment effect was observed in metabotype B in the liver at 7 d PP, characterized by an increase in several acylcarnitines and phosphatidylcholines, indicating a more efficient influx and oxidation of fatty acids in mitochondria and thereby an increase in energy supply and more efficient triglyceride export in the liver. The results from the liver metabolomics analysis support the application of an indication-based metaphylactic treatment with BCC.

Infectious complications and graft outcome following treatment of acute antibody-mediated rejection after kidney transplantation: A nationwide cohort study.

Acute antibody-mediated rejection (AMR) remains a challenge after kidney transplantation (KT). As there is no clear-cut treatment recommendation, accurate information on current therapeutic strategies in real-life practice is needed. KT recipients from the multicenter Swiss Transplant Cohort Study treated for acute AMR during the first post-transplant year were included retrospectively. We aimed at describing the anti-rejection protocols used routinely, as well as patient and graft outcomes, with focus on infectious complications. Overall, 65/1669 (3.9%) KT recipients were treated for 75 episodes of acute AMR. In addition to corticosteroid boluses, most common therapies included plasmapheresis (56.0%), intravenous immunoglobulins (IVIg) (38.7%), rituximab (25.3%), and antithymocyte globulin (22.7%). At least one infectious complication occurred within 6 months from AMR treatment in 63.6% of patients. Plasmapheresis increased the risk of overall (hazard ratio [HR]: 2.89; P-value = 0.002) and opportunistic infection (HR: 5.32; P-value = 0.033). IVIg exerted a protective effect for bacterial infection (HR: 0.29; P-value = 0.053). The recovery of renal function was complete at 3 months after AMR treatment in 67% of episodes. One-year death-censored graft survival was 90.9%. Four patients (6.2%) died during the first year (two due to severe infection). In this nationwide cohort we found significant heterogeneity in therapeutic approaches for acute AMR. Infectious complications were common, particularly among KT recipients receiving plasmapheresis.

Eighth-year survival and growth of planted replacement tree species in black ash (Fraxinus nigra) wetlands threatened by emerald ash borer in Minnesota, USA

Black ash (Fraxinus nigra) is native to lowland forests of the western Great Lakes region, USA, where it often comprises a majority of trees. Like all native ash in North America, black ash is threatened by emerald ash borer (EAB; Agrilus planipennis), but the impacts from EAB mortality may be particularly severe in these forests given the foundational role of black ash at regulating ecosystem function. Compounding the problem is that associated tree species occur in low abundance and their abundance may be further reduced as habitat declines with climate change. These converging threats point to the need for silvicultural intervention to establish replacement tree species in anticipation of EAB invasion. Here we report on a large-scale management experiment from Minnesota, USA that includes different silvicultural approaches for establishing replacement tree species in black ash forests. Specifically, we examined eighth-year survival and growth of planted seedling in treatments that included clearcutting, group selection, uncut forest, and emulation of EAB mortality by girdling black ash. Species included nine that are native to the ecosystem, two from the next southern climate zone, and one exotic species, Manchurian ash (Fraxinus mandshurica). Among species and treatment combinations, survival was highest for American elm (Ulmus americana), averaging around 81% in uncut, group selection, and girdle treatments. Swamp white oak (Quercus bicolor), a species from the next southern climate zone, also had high survival in these treatments (ranging from 61% to 79%). Both species had survival under 60% in the clearcut treatment. Most native southern boreal species, as well as Manchurian ash, had low survival (0% to less than 40%) in most treatments. In the clearcut, girdle, and group selection treatments relative diameter and relative height growth was highest for balsam poplar (Populus balsamifera), averaging, respectively, around 0.25 mm mm−1 yr−1 and 0.20 cm cm−1 yr−1, followed by swamp white oak and red maple (Acer rubrum). Non-native Manchurian ash had consistently low growth in all treatments compared to other species. All species had low growth rates in the uncut treatment. An integration of survival and diameter growth pointed to group selection as the treatment that provides the best balance between survival and growth. Our results indicate promising survival and growth of at least some replacement species, including several predicted to be future climate-adapted, as well as a silvicultural approach in group selection that is an effective method to regenerate these species.

Soil Biodiversity as Affected by Different Thinning Intensities in a Pinus laricio Stand of Calabrian Apennine, South Italy

Forest soil biodiversity, which drives natural ecosystem multifunctionality, can be altered by incorrect forestry management practices. Pinus laricio is the most representative and widespread conifer species in Calabria, South Italy, and appropriate management is needed to maintain Pinus laricio forest for its great economic and natural value. In Europe, thinning is considered the most effective silvicultural treatment to maintain/increase the ecological value of coniferous stands. In this study, moderate thinning (MT), intense thinning (HT), and clear cut (CC) treatments were used to manage Pinus laricio stands with the aim of identifying the thinning intensity that is less detrimental to soil biodiversity. The effects of the different thinning intensities were evaluated, in two contrasting seasons (summer and winter), on the abundance, and diversity of arthropods, fungi, and bacteria colonies as well as on selected soil properties (organic matter, humification index, bulk density, pH) related to soil habitability. Results evidenced that the abundance, species richness, and diversity of arthropods, as well as fungi, bacteria colonies, and soil properties, changed with the treatments and seasons. Under HT, the greatest biodiversity and the highest amounts of arthropods, fungi, and bacteria were found in both seasons. This study finds evidence for Connell’s intermediate disturbance hypothesis, highlighting that the greatest organic carbon content and humification index, as well as the lowest bulk density, found in HT reduced the likelihood of competitive exclusion between occurring species, thereby promoting high species richness and diversity. This study gives insights into ecological relationships between understory composition related to tree species abundance and soil community.

Girdling of young Robinia pseudoacacia trees on the Tama River terrace, central Japan

Robinia pseudoacacia L. has been widely planted worldwide for a variety of purposes, but it is an aggressive invader in many regions. To control invasion by the species, we examined the effectiveness of girdling young trees to ground level to kill trees and preclude sprout development through comparison among girdling, clearcut and control treatments on the Tama river terrace, Tokyo. More than 99% of R. pseudoacacia trees were killed by girdling. The number of sprouts that developed from roots and stumps after girdling was distinctly reduced compared with that observed after clearcutting. We also conducted girdling of young trees of Ailanthus altissima (Mill.) Swingle, which shows similar developmental and ecological characteristics to R. pseudoacacia, and the two species are often sympatric. More than 98% of A. altissima trees were killed, but a higher number of sprouts developed from A. altissima stumps compared with that from R. pseudoacacia stumps. These results indicate that girdling young trees to ground level is an effective method of controlling R. pseudoacacia by killing the stem and precluding sprout development. The girdling method is simple to apply and imposes a low burden on the surrounding environment.

Fertilization and clear-cutting effects on greenhouse gas emissions of pinewood nematode damaged Masson pine plantation

ABSTRACT Introduction: Management practices are essential for maintaining forest ecological functions under increasing diseases and pest disasters. The effects of nitrogen fertilization (NF) and clear-cutting (CC) on the soil microbial community structure and greenhouse gases emission were investigated of pinewood nematodes (Bursaphelenchus xylophilus)-infected Masson pine (Pinus massoniana) plantations. Outcomes: CC increased the soil microbial biomass carbon (SMBC) and soil microbial biomass nitrogen (SMBN) contents relative to the control (CK). NF increased the SMBN but had no significant effect on the SMBC content. The total fungal and bacterial abundances increased in the CC treatment compared with the CK, but there was no significant difference between the NF and CK. The cumulative soil CO2 emission (2.35 t C·hm−2) was higher than that of CK (1.65 t C·hm−2) in summer, and the cumulative annual N2O emission (16.90 kg N·hm−2 yr−1) of NF was approximately 47 times of CK (0.36 t N·hm−2·yr−1). CC increased the CO2 flux (2.21 t C·hm−2) in summer but have no significantly effects on N2O emission. Conclusion: These results indicated that NF and CC practices changed forest soil microbial community structure and affected soil greenhouse gas emissions in pinewood nematodes -infected Masson pine plantations. The CO2 emission rates increased in the NF and CC treatments, which reduced the carbon sequestration function of forests and had a negative impact on climate change.

Performance Comparison for Two Cable Extraction Machines in a Larix kaempferi (Lamb.) Carr. Plantation

Forests in Korea are mainly located in steep mountainous areas, where small-shovel-based extraction technology is widely used, with the level of mechanization undoubtedly low due to financial limitations. On this steep terrain, a better approach may be to use cable yarders, which can offer high revenues through cable-based extraction. Therefore, improving the efficiency of cable yarding activities in good-quality timber forests is necessary. The main objectives of this study were to (1) evaluate the productivity and cost of a cable yarder operation for tree-length clearcut treatment of a Larix kaempferi (Lamb.) Carr. stand and (2) compare the productivity efficiency of two yarder (K301-4 and HAM300) types. The productivity rates of the K301-4 ranged from 10.2 to 12.5 m3/productive machine hours, with corresponding costs of US $12.6–15.4 /m3. The productivity of the HAM300 was 26% lower than that of the K301-4 for a 30% lower cycle log volume while yarding and a comparable lateral distance. This study provides insights to support production and management decisions in the forest supply chain associated with planning cable-yarding operations.

Curbing the Spread of COVID-19 Pandemic Caused by SARS-CoV-2: Considering Psychological, SocioLegal and Ethical Implications on Preventive Measures in Cameroon

The emergence of human to human novel Coronavirus disease (COVID-19) in Wuhan, China rapidly became a global pandemic and it ultimately lead towards medical, legal and ethical concerns which need to be addressed. As compared to current zoonotic infections, the spread of COVID-19 is exceptional; with higher severity as well as more confirmed mortality. The mode of transmission is primarily through respiratory droplets with incubation times (1 – 14 days) which is quite similar to severe acute respiratory syndrome coronavirus (SARS-CoV-1). Reports show that it has claimed more lives as compared to the Middle East respiratory syndrome coronavirus (MERS-CoV). Till now, it is difficult to present a clear conclusive information about the prevention as well as the spread of this viral infection and therefore no clear cut treatment guidelines are available. Hence, it is difficult to project how to live with this viral infection, the Government of many countries including Cameroon have provided some public health measures to help in the reduction of its spread. These measures include amongst others; isolation, quarantine, social distancing, regular washing of hands with soap, use of hand sanitizers, staying and working from home and obligatory wearing of masks in public places. Proper implementation of these measures require relevant and effective communication as well as sensitization projects to be put in place to abreast the community and individuals to comply with the procedures. It is the inherent role of the Government of Cameroon to ensure that adequate supplies of essential needs (masks, clean water, soap, hand sanitizers) are available for the vulnerable and underprivileged members of society during this health crisis. Here, we are going to explore the psychological, socio-economic, and ethico-legal concerns of this pandemic, through its implementation of isolation, quarantine, social distancing, constant washing of hands with soap, use of hand sanitizers, staying and working from home, obligatory wearing of masks in public places and national lockdown. The implication of these measures on the life of the population in a low middle income country like Cameroon has been elucidated.

Regenerating mixed bottomland hardwood forests in north Missouri: Effects of harvest treatment on structure, composition, and growth through 15 years

Bottomland forest ecosystems provide important economic and ecological benefits within the midwestern and southern United States, yet silvicultural guidelines for reaching management objectives have been poorly developed outside the southeastern region. Bottomland hardwood forests are highly productive and dynamic ecosystems that contain a multitude of herbaceous and woody plant species and can support an abundance of wildlife throughout stand development. In particular, oak species are often favored for timber and wildlife values but may occur in low abundance due, in part, to challenges with regeneration. This study was designed to examine the structure and composition of a mixed bottomland hardwood forest (elm/ash/cottonwood) in northeast Missouri in response to two regeneration harvest treatments (i.e., clearcut with reserves and basal area retention) and one unharvested control through 15 years after harvest. Results indicate that clearcutting had a greater effect on subsequent forest composition and stand development than partial harvesting. In particular, the clearcutting treatment increased the relative basal area of American elm and relative abundance (trees per hectare) of green ash. Results suggest that the regeneration harvests did not increase the abundance of oak regeneration. However, the growth rates and the size of oak stems within the regeneration cohort were comparable to competing species, suggesting the oaks within the regeneration cohort presumably originated from advance reproduction. Thus, these results support the importance for establishing oak advance reproduction prior to regeneration harvest within bottomland forests.