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Translocations, a conservation tool used to conserve and restore dwindling species, are often associated with high failure rates. Inadequate long‐term monitoring of both populations and their introduction sites beyond the initial years post‐translocation creates a gap in our understanding of the factors that determine translocation success or failure, resulting in less informed projects in the future. This lack of long‐term monitoring is partly caused by the absence of a well‐defined framework by which the success of the translocation can be measured, leading to premature and sometimes inaccurate assessments of their outcome. We investigated the long‐term outcome of a red squirrel translocation in the west of Ireland, specifically assessing the habitat changes in the translocation site since the introduction in 2005, and their impact on the capacity of the forest to sustain a population of a given size. Using digitised historical map data, we showed that the translocation site experienced a 53% reduction in suitable habitat. Additionally, there was a 41%–81% reduction in the total number of red squirrels the forest could support, according to feeding survey data. Clear‐felling, a forest fire and a shift in tree species composition collectively contributed to this decline in site suitability. This investigation underscores the complexity of translocation projects and emphasises the pivotal role of habitat quality in their outcomes. We advocate for detailed habitat assessments during the planning phase, avoidance of unstable habitats as translocation sites, and the implementation of long‐term monitoring practices. Translocations often face high failure rates, due in part to our lack of understanding of their long‐term outcomes. We investigated long‐term outcome of a red squirrel translocation in the west of Ireland, focusing on habitat loss and changes in carrying capacity. We found a 53% reduction in suitable habitat and a 41%–81% decline in carrying capacity, emphasising the importance of detailed habitat assessments and the use of stable sites for successful translocations. [ABSTRACT FROM AUTHOR]

The ongoing loss of red‐listed coastal heathlands is a threat to biodiversity and cultural heritage legacies throughout the Atlantic coastal regions of Europe. It is possible to restore degraded and afforested heathlands, but restoration interventions are often labour‐intensive and costly, and the outcome of specific restoration actions are not well documented. We assess the efficiency of restoring coastal heathlands through natural succession (i.e. 'passive restoration') after removal of Sitka spruce Picea sitchensis (Bong.) Carr. plantations. The study was replicated on two neighbouring islands in a nature reserve in Western Norway. Low‐intensity free‐range sheep grazing was implemented as part of the reserve management plan. Furthermore, we tested the effect of leaving the clear‐felled woody material as chips on site, this being a cost‐efficient strategy on islands. Succession was monitored 1, 2, 4/5 and 8 years after clear‐felling, and revegetation of vascular plants and bryophytes was compared to target heathland vegetation. Surprisingly, we found different successional trajectories on the two islands. Species composition on one island approached target heathland vegetation during succession, but not on the other. Wood chips reduced species richness and slowed the restoration process, but these negative effects were only short‐term (<8 years). Differences in seed bank composition and soil conditions due to land use may explain the deviating successional trajectories on the two islands. We also found that management actions beyond clear‐felling and introducing sheep grazing are necessary due to the rapid seed regeneration of the Sitka spruce. [ABSTRACT FROM AUTHOR]

Air quality, cool air temperatures, as well as captured carbon are enhanced by trees on campus. Human activities in and around academic areas within the university indicate possible high level of Carbon dioxide in thoe specific areas. Therefore, the objective of this study is to assess the Carbon capture potentials of indigenous trees in selected academic area parks (COLAMRUD Park, COLANIM Park, COLERM Park, Motion Ground Park and Multi-purpose Building Park) of Federal University of Agriculture Abeokuta, Nigeria using a non-destructive sampling technique. Results show that there are a total of 10 different tree species across the parks some of which include; Azadiratcha indicia, Albezia lebbeck, Entandrophragma cylindricum, Khaya senegalensis and Mangifera indica. The weight of Carbon captured was observed to be highest in the Entadophragma cylindricum (19.68 x 106 kgm-2) followed by Cedrela ordorata (10.84 x 106 kgm-2) while the least was Cola millenni (1.43 x 106 kgm-2). Carbon capture potential was significantly (p<0.05) higher (2.90 x 106) at MPB park when compared with others. The native species carbon sequestration order is; EC>SS>CO>MI>AI>AL>KS>SM>TR>PL. The presence of trees on university campus boosts carbon sequestration, clear-felling of these trees species while constructing new structures should be extremely reduced and more trees should be introduced in places with much human daily activities. [ABSTRACT FROM AUTHOR]

Air quality, cool air temperatures, as well as captured carbon are enhanced by trees on campus. Human activities in and around academic areas within the university indicate possible high level of Carbon dioxide in thoe specific areas. Therefore, the objective of this study is to assess the Carbon capture potentials of indigenous trees in selected academic area parks (COLAMRUD Park, COLANIM Park, COLERM Park, Motion Ground Park and Multi-purpose Building Park) of Federal University of Agriculture Abeokuta, Nigeria using a non-destructive sampling technique. Results show that there are a total of 10 different tree species across the parks some of which include; Azadiratcha indicia, Albezia lebbeck, Entandrophragma cylindricum, Khaya senegalensis and Mangifera indica. The weight of Carbon captured was observed to be highest in the Entadophragma cylindricum (19.68 x 106 kgm-2) followed by Cedrela ordorata (10.84 x 106 kgm-2) while the least was Cola millenni (1.43 x 106 kgm-2). Carbon capture potential was significantly (pSS>CO>MI>AI>AL>KS>SM>TR>PL. The presence of trees on university campus boosts carbon sequestration, clear-felling of these trees species while constructing new structures should be extremely reduced and more trees should be introduced in places with much human daily activities.

Soil water content is an important hydrological parameter, which is difficult to measure at a field scale due to its spatial and temporal heterogeneity. The Cosmic Ray Neutron Sensor (CRNS) is a novel and innovative approach to estimate area-averaged soil water content at an intermediate scale, which has been implemented across the globe. The CRNS is moderated by all hydrogen sources within its measurement footprint. In order to isolate the soil water content signal from the neutron intensity, the other sources of hydrogen need to be accounted for. The CRNS’s applications are not only limited to soil water content estimation, as it can potentially be used to monitor biomass. The Two-Streams clear-felling provided the unique opportunity to monitor the cosmic ray neutron intensities before, during, and after the clear-felling. The cadmium-difference method was used to obtain the pure thermal and epithermal neutron intensities from the bare and moderated detectors. The study concluded that the presence of biomass within the site reduced the epithermal neutron intensity by 12.43% and the N0 value by 13.8%. The use of the neutron ratio to monitor biomass was evaluated and changes in the neutron ratio coincided with biomass changes and resulted in a high correlation (R2 of 0.868) with the normalized difference vegetation index (NDVI) and (R2 of 0.817) leaf area index (LAI). The use of the CRNS to simultaneously monitor soil water content and biomass will be beneficial in providing more reliable soil water content estimates, provide biomass estimates at a field scale, and aid in understanding the dynamics between soil water content and vegetation.

Time series of satellite sensor data have been used to quantify mangrove cover changes at regional and global levels. Although mangrove forests have been monitored using remote sensing techniques, the use of time series to quantify the regeneration of these forests still remains limited. In this study, we focus on the Matang Mangrove Forest Reserve (MMFR) located in Peninsular Malaysia, which has been under silvicultural management since 1902 and provided the opportunity to investigate the use of Landsat annual time series (1988–2015) for (i) detecting clear-felling events that take place in the reserve as part of the local management, and (ii) tracing back and quantifying the early regeneration of mangrove forest patches after clear-felling. Clear-felling events were detected for each year using the Normalized Difference Moisture Index (NDMI) derived from single date (cloud-free) or multi-date composites of Landsat sensor data. From this series, we found that the average period for the NDMI to recover to values observed prior to the clear-felling event between 1988 and 2015 was 5.9 ± 2.7 years. The maps created in this study can be used to guide the replantation strategies, the clear-felling planning, and the management and monitoring activities of the MMFR.

Sufficiency of potassium (K) is one of the biggest concerns for forestry in boreal peatlands, since the rooting zone stores of K in thick peat soils are generally small and significant proportion of the K in ecosystem is bound in stand biomass. Increased demand for bioenergy may lead to intensified harvesting also in such forests. There is thus an urgent need to study the significance of the nutrients in harvest residues for the next-generation forest productivity. The specific questions in peatland forests are whether the harvest residues are an important source of K to the restock or whether the K in harvest residues is lost by leaching. We quantified K losses from drained peatland forests following management by clear-felling with stem-only harvesting (SOH), whole-tree harvesting (WTH) and whole-tree harvesting plus stump harvesting (WTHS). Calibration period – control area method and mixed modelling approach were used to analyze the ditch-outflow K-concentration and water-borne K-export data from 17 harvested and 5 control catchments in southern and central Finland. K concentrations and runoff were monitored for 1–2 years before and 3–4 years after treatment. Supplementary long-term data from one pair of harvested and non-managed catchments was used to assess the duration of the harvest impact on K export. Mean annual K concentrations in ditch outflow were higher after than before harvesting. The concentrations started to increase during the second or third post-harvest year, reaching the peaks of 1.1–2.2 mg L −1 in WTHS, 0.8–1.7 mg L −1 in WTH, and 1.0–1.9 mg L −1 in SOH. The concentrations correlated positively with the amount of K in the surface peat. In nutrient-poor ombrotrophic sites, the K concentrations were higher for sites with shallower water-table level. Using the supplementary data, the impact of harvesting on K losses was estimated to last for about eight years. The overall estimated K loss was about 28 kg ha −1 from minerotrophic sites, and about 9 kg ha −1 from ombrotrophic sites. There was no significant difference in K losses between the harvest treatments SOH, WTH and WTHS, indicating that the K in harvest residues was largely retained onsite. The role of K losses induced by harvesting in the site K stores in drained peatland forests is discussed. [ABSTRACT FROM AUTHOR]

Timber-oriented forest management causes significant changes to the environments, threaten the survival of many native species and it is responsible for the primary forest loss. Recognition of the scale and effects of the primary forest loss has resulted in a considerable degree of interest in the restoration. One of the serious efforts at restoration is the compulsory reforestation of the clear-felled stands of any (native or non-native) forests with native species. To evaluate the success of restoration efforts it is important to answer whether the diversity and composition of indigenous assemblages can recover after reforestation with native trees and to know how long is the recovery time? We studied ground beetles and millipedes from mature (130-year-old) oak forest, and recently established (5-year-old), young (15-year-old), and middle-aged (45-year-old) reforestation with native English oak by pitfall trapping and leaf litter sifting to assess the recovery dynamics of their diversity and composition. The overall number of the ground beetle individuals and species were significantly the highest in the 5-year-old reforestation, while the overall number of millipede individuals and species were significantly the lowest in the recently established reforestation. The elevated overall number of ground beetle individuals and species in the 5-year-old reforestation were due to the colonization of good disperser open-habitat species. The number of forest-associated ground beetle individuals and species were significantly the lowest in the 5-year-old reforestation, whereas from 15 years after the reforestation, when the canopy has been closing, there was no significant difference in the number of forest species. The number of forest-associated millipede individuals and species were significantly the lowest in the 5-year-old reforestation; however, they were significantly the highest in the natural mature oak forest. Results of both the ordination and the quantitative character species analysis also confirmed that reforestation with native oak after mechanical soil treatment had detrimental effects on both studied ground-dwelling arthropod groups. The diversity and composition of ground beetles with high dispersal ability and less specific feeding habit recovers after the closure of the canopy, while similar recovery do not occur regarding millipedes with low dispersal ability and specific feeding habit. Our results suggest that soil preparation and light tilling should be omitted during the reforestation and cultivation of the reforested stands. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied P export after clear-felling from Scots pine dominated peatlands in Finland. [•] The water table level was the most significant factor contributing to the P export. [•] The harvest method was not significant in explaining harvest-induced P loads. [•] The peat P sorption characteristics were not significant in explaining the P loads. [Copyright &y& Elsevier]

Abstract: There is currently only limited understanding of the influence of conifer plantation management on soil carbon (C) and nitrogen (N) storage in maritime Europe. The study reported herein examined the effect of clear felling on belowground C and N stocks, and CO2 effluxes at paired clear-felled, and standing plantation sites in North Wales. Clear-felled conifer stands were compared in three different time lapses (3, 5 and 8years after harvesting). The O horizon (and associated C) was completely absent on the year 3 and year 8 clear-felled stands. There was no significant influence of clear-felling on mineral soil C and N at 0–10cm depth between clear felled and unharvested sites, however, differences were observed in subsoil depths (10–20cm and 20–50cm). Clear-felled sites exhibited an initial gain in surface soil C and N through year 5 (likely due to incorporation of the O horizon into the mineral soil) after which the C stock decreased by year 8. Approximately 50Mg C and 3MgN ha−1 yr−1appear to have been lost from mineral soils 7years after clear felling. Clear felling significantly (p <0.05) increased soil CO2 efflux and soil surface temperature. Total CO2 emission from soils at clear felled sites was 148% higher than that of uncut plantations. Alternative harvest strategies should be considered that reduce C losses from plantations in North Wales. [Copyright &y& Elsevier]

Establishing soil quality changes following clear-felling is important for guiding the sustainable management of forests. In this study we identified changes after 4, 5, 10 and 17 yr in soil physical and chemical properties from clear-felling in the eastern Tibetan Plateau. These properties were also compared with those of soil from an adjacent primary forest. The results show that: (i) bulk density at 0-20 and 20-40 cm soil layer continuously increased; (ii) soil C and total N in the 0-20 cm soil layer continuously declined following clear-felling; and (iii) available soil nutrients and exchangeable cations were significantly influenced by clear-felling. Almost all soil properties showed deteriorating trends within a short time from clear-felling and subsequent seasonal grazing by cattle. Therefore, improved management is imperative for sustaining soil quality and maintaining the long-term nutrient balance in clear-cut stands. The cessation of anthropogenic activities such as grazing should be the main strategy for soil restoration in clear-felled areas. [ABSTRACT FROM AUTHOR]

To evaluate the effect of increasing forest disturbances on greenhouse gas budgets in a taiga forest in eastern Siberia, CO2, CH4 and N2O fluxes from the soils were measured during the growing season in intact, burnt and clear-felled larch forests (4–5 years after the disturbance). Soil temperature and moisture were higher at the two disturbed sites than at the forest site. A 64–72% decrease in the Q10 value of soil CO2 flux from the disturbed sites compared with the forest site (5.92) suggested a reduction in root respiration and a dominance of organic matter decomposition at the disturbed sites. However, the cumulative CO2 emissions (May–August) were not significantly different among the sites (2.81–2.90 Mg C ha−1 per 3 months). This might be because decreased larch root respiration was compensated for by increased organic matter decomposition resulting from an increase in the temperature and root respiration of invading vegetation at the disturbed sites. The CH4 uptake (kg C ha−1 per 4 months [May–September]) at the burnt site was significantly higher (–0.15) than the uptake at the forest (–0.045) and clear-felled sites (0.0027). Although there were no significant differences among the sites, N2O emission (kg N ha−1 per 4 months) was slightly lower at the burnt site (0.013) and higher at the clear-felled site (0.068) than at the forest site (0.038). This different influence of burning and tree felling on CH4 and N2O fluxes might result from changes in the physical and chemical properties of the soil with respect to forest fire. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the composition and dynamics of soil seedbanks beneath mature conifer plantations is important for managing biodiversity in rotational forestry systems and in the restoration of former communities following the removal of tree crops. We examined the role of the buried seedbank in vegetation development after clear-felling of stands within coniferous plantation forest in eastern England. The buried seedbank of 29 mature stands planted in the early to mid 20th century on lowland heathland and marginal arable was determined by germination of seeds from soil cores (30 bulked cores per stand). Seedbank density was highly variable, with a mean of 3950 (S.D.±2400)seedsm−2. Ninety-eight species germinated, of which 37 were present in the surface vegetation of the mature stands; these 37 species had a higher density of seeds than the 61 species absent from the surface vegetation. Of those 61 species, 21 were recorded in the surface vegetation of recently replanted stands, suggesting that the seedbank may increase the plant diversity of replanted stands following clear-felling. The seedbank of mature stands was dominated by Urtica dioica and Holcus lanatus. Comparison of seeds in the top 20cm of soil between four paired mature and replanted stands showed felling and cultivation prior to replanting had little effect on either the density of the buried seedbank or the vertical seed density profile. Twenty-nine of the species recorded in the buried seedbank of mature stands were characteristic of heathland assemblages of the region, but were present at low densities. Notably, a number of perennial grass species characteristic of heathland were absent, while Calluna vulgaris occurred in the seedbank of few stands and then at low density. The potential for grass-heath restoration following clear-felling of first rotation conifer stands investigated in this study is likely to be low. [Copyright &y& Elsevier]

Abstract: The long-term effects of nitrogen fertilization on ground vegetation were examined at three coniferous forests sites where the last N fertilization had been carried out 15–18 years previously and clear-felling 5–12 years previously. At the Farabol site in S Sweden, with Norway spruce and ground vegetation dominated by Deschampsia flexuosa, the total N dose (600kgha−1) had been applied with or without sulphur. At the Norway spruce site Mangskog in SW Sweden, the vegetation prior to clear-felling was dominated by low herbs and Vaccinium myrtillus, and total N dose had ranged from 480 to 2400kgNha−1. At the Scots pine site Billingsjön in C Sweden, total N dose had ranged from 360 to 1800kgNha−1, the vegetation was lichen-rich and dwarf shrubs dominated prior to clear-felling. The abundance of species in the field and bottom layers was analyzed both by observations of species presence and by examination of point-intercept records. The results show that nitrogen fertilization has led to a long-term reduction in the abundance of epigeic lichens. This was particularly the case for Cladina rangiferina, which was reduced by 50% at total doses of the order of 1000kgNha−1. Nitrogen fertilization also resulted in decreased cover of common mosses at Mangskog (Pleurozium schreberi, Hylocomium splendens) and Billingsjön (Dicranum fuscescens, Dicranum scoparium, Polytrichum juniperum). However, nitrogen fertilization did not result in more dense field layer or bottom layer vegetation after clear-felling, and there was no evidence that the abundance of nitrophilic herbs or grasses, otherwise reported to increase after fertilization, had been influenced. The most pronounced effects of N fertilization were observed at the nutrient-poor and lichen-rich site Billingsjön, indicating that the effects of N fertilization have a tendency to be more pronounced on nutrient-poor sites than on nutrient-rich. The relatively marked effects at Billingsjön were better correlated with the observed retention of the fertilizer in the soil after clear-felling than with the total load applied previously. This finding suggests that any change in the nitrogen storage of soils can cause changes in the natural vegetation. This study also demonstrates clearly that effects of nitrogen fertilization on ground vegetation persist for a reasonably long time after clear-felling. However, since the overall vegetation type was not altered on any of the three sites, we consider the long-term, overall effect of nitrogen fertilization to be of moderate magnitude. [Copyright &y& Elsevier]

Drainage of waterlogged sites has been part of the normal forestry practice in Fennoscandia, the Baltic countries, the British Isles and in some parts of Russia since the early 20th century, and currently, about 15 million hectares of peatlands and other wetlands have been drained for forestry purposes. The rate of forest clear-felling on drained peatlands will undergo a rapid increase in the near future, when a large number of these forests approach their regeneration age. A small-scale pilot survey was performed at two nutrient-rich and old peatland drainage areas in southern Finland to study if forest clear-felling has significant impacts on the exchange of nitrous oxide (N2O) and methane (CH4) between soil and atmosphere. The average N2O emissions from the two drainage areas during three growing seasons following clear-felling were 945 and 246 μg m-2 d-1. The corresponding CH4 fluxes were -0.07 and -0.52 mg m-2 d-1. Clear-felling had impacts on the environmental factors known to affect the N2O and CH4 fluxes of peatlands, i.e. clear-felling raised the water table level and increased the peat temperature. However, no substantial changes in the fluxes of CH4 following clear-felling were observed. The results concerning N2O indicated a potential for increased emissions following clear-felling of drained peatland forests, but further studies are needed for a critical evaluation of the impacts of clear-felling on the fluxes of CH4 and N2O. [ABSTRACT FROM AUTHOR]

Following the tree harvest, the biogeochemistry of a catchment is modified by changes in soil temperature and moisture, and nutrient cycling. We monitored soil-solution and stream-water chemistry, and soil properties in a Pinus radiata D. Don plantation in New Zealand before and after clear-cutting and replanting in 1997. The annual rainfall during the study was 1440–1860 mm. The soil was a 1800-year-old pumice soil of high natural N status; the catchment had received large inputs of volcanic N in rain, probably over the 1800 years since the pumice had been deposited. The leaching loss of nitrate-N was 28 kg ha−1 yr−1 in 1996, and then decreased sharply after clear-cutting to 3 kg ha−1 yr−1 in 1998 and <1 kg ha−1 yr−1 in 1999. Weed growth and soil microbial biomass increased during this time, and would have removed much of the N from soil solution in the upper soil layers. Although the catchment was small (8.7 ha), there was a 2-year lag until N decreased in stream-water; the losses of dissolved organic N to stream-water were low. There was no change in soil pH over the 4 years, but spring-water pH appeared to increase, which was consistent with the increase in bicarbonate that accompanied grass/weed growth. The export of cations (mmolc l−1) in the spring-water was Na>Ca>Mg=K as expected for rhyolitic pumice, and the total concentration was probably controlled by the accompanying anions. The export of anions was NO3=Cl>SO4=HCO3 before harvest and HCO3=Cl>SO4=NO3 after harvest. [Copyright &y& Elsevier]

We used 2 long-term field experiments with Norway spruce Picea abies (L.) Karst. to investigate the influence of lime, acid sulphur compounds, or nitrogen (1 site) on the rate of recruitment of new vascular species after clear-fellings. On the study sites, Farabol in southern Sweden and Fa¨xboda in south–central Sweden, the chemical treatments had been applied before clear-felling and whole-tree harvesting. An additional, post-harvest experiment was conducted at Farabol in which lime, hardened wood-ash, or logging residues were applied. A germination experiment including seven species was carried out in a greenhouse using sifted humus from Fa¨xboda that was sampled 2 years before clear-felling.The clear-fellings resulted in establishment of many ephemeral species. The number of newly established species was greater than the number of disappeared species.There was an overall positive correlation with pH in the humus layer and the number of newly established species. The treatment effects differed between the sites, probably reflecting differences in total dose and initial soil conditions. Farabol is characterised by more acid soils and greater atmospheric deposition of S and N than Fa¨xboda. At Farabol, liming (in total 6000 kg limestone ha−1 distributed over 12 years) resulted in about 20 new species established after clear-felling, four times more species than in untreated, sulphur-treated, or nitrogen-fertilised plots. At Fa¨xboda, where lime (2000 kg dolomite ha−1), sulphuric acid, and elementary S had been applied 16 years before clear-felling, the number of newly established species was about 15, and no effect of the treatments was revealed.The post-harvest treatments at Farabol showed that wood-ash and logging residues had similar effects as lime on the establishment of new species.The pot experiment showed that liming or acidification can affect the germination of seeds. Compared with untreated soil, a greater proportion of seeds of Primula veris (P. veris) and Senecio sylvaticus (S. sylvaticus) germinated in limed soil and the germination of P. veris was lower in acid- or sulphur-treated soils. The germination of Vaccinium myrtillus (V. myrtillus) seeds was negatively affected by liming. No effects of the treatments were discovered on the germination of Deschampsia flexuosa, Calamagrostis arundinacea, Galeopsis bifida (G. bifida), or Poa nemoralis. The soil water in the pot experiment had higher pH, higher concentrations of Ca and Mg, and higher NO3−/NH4+ ratios in limed soil compared with other treatments.Nomenclature of plants follows . [Copyright &y& Elsevier]

Soil respiration was measured throughout the year (June 1992 to May 1993) in a mature, deciduous, broad-leaved forest and an adjacent, clear-felled stand which was made in November 1991, in Hiroshima Prefecture, west Japan. The same soil temperature and soil moisture content as those in the forest stand were maintained in two frame boxes covered with sheets of white netting in the clear-felled stand to observe soil respiration. A herbicide was applied to the cut end of all stumps in one of the two frame boxes in order to kill the root system. There was no significant difference in the aboveground biomass and soil environmental conditions between the forest and the frame boxes in the clear-felled stands. The difference in soil respiration rate between the forest and the frame box, in which the root system was killed by the herbicide, was considered to be due largely to the contribution of root respiration. Taking into consideration CO evolution due to the decomposition of roots killed and the change in A layer respiration rate after clear-felling, the proportion of root respiration to the total soil respiration before clear-felling was estimated to be 51% annually, which coincides closely with those values estimated previously in mature forests by other methods. The difference in the soil respiration rate between the two frame boxes (one with killed roots and the other with undisturbed roots) suggested that the annual root respiration rate just after clear-felling dropped to about two-thirds (70%) of that before clear-felling. [ABSTRACT FROM AUTHOR]

Cycling of soil carbon in the first year after a clear-felling was compared with that before the felling in a Japanese red pine forest in Hiroshima Prefecture, west Japan. The daily mean temperature at the soil surface in summer was increased after the felling in comparison to that before felling, and the water content of both the A layer and the surface mineral soil was decreased due to the loss of the forest canopy. The rate of weight loss of the A layer was reduced after felling. However, accumulation of the A layer rapidly decreased because of the lack of litter supply to the forest floor. Low soil respiration after felling was mainly caused by the cessation of root respiration. Analysis of annual soil carbon cycling was then conducted using a compartment model. The relative decomposition rate of the A layer decreased whereas that of humus and dead roots in mineral soil increased to some extent after felling. The accumulation of carbon in mineral soil, however, increased slightly due to the supply of humus from roots killed by the felling. [ABSTRACT FROM AUTHOR]

• Clear-felling an upland Sitka spruce resulted in a strong annual CO 2 emission. • The magnitude of the CO 2 source was similar to the sink of a mature stand. • Two years after replanting the clear-fell was a weak source. • Drought in 2018 reduced net CO 2 uptake of the mature stand by 30%. • Drought turned the clear-fell into a CO 2 source due to increase in respiration. Sitka spruce is the major conifer species in British upland forests and is predominantly managed as even-aged, single-species plantations with rotation lengths of less than 50 years using a "patch clear-felling" system. Evidence on the impact of clear-felling on the carbon, water and energy balances of plantation forestry is sparse and extreme weather events, such as the 2018 drought that occurred across Europe, are expected to have considerable impact. We used energy balance and gas flux data from a typical mature stand and a clear-felled site on peaty-gley soil at Harwood Forest in Northumberland, UK, over 4 years to quantify the impact of clear-felling and investigate how the drought of 2018 affected these fluxes. Felling resulted in an annual CO 2 source (7.05 tC ha − 1 yr − 1 ) of similar magnitude in absolute terms to the mature stand sink (−7.09 tC ha − 1 yr − 1 ). The source was reduced with the growth of ground vegetation, and after tree replanting two years post-felling, the site was a weak source. Felling increased reflected radiation by 92%, reduced evapotranspiration by 28% and therefore increased site wetness by 8%, while replanting and the spread of ground vegetation increased evapotranspiration by 16% on average. The warm, dry spring and summer in 2018 increased evapotranspiration and reduced net carbon uptake of the mature stand by 30% compared to the mean of the previous three years, because of a small decrease in photosynthetic uptake and a small increase in ecosystem respiration. The drought conditions also increased ecosystem losses of CO 2 at the clear-felled site by 28%. The clear-fell site would have turned into a small CO 2 sink in the second year after replanting, if there had not been a drought. [ABSTRACT FROM AUTHOR]

• Effects of clearcutting on small mammals are species-specific. • Species responses are related to their movement and reproductive behavior. • Sedentary species stayed in harvested stands resulting in high mortality. • Mobile species evacuated from harvested stands and relocated to undisturbed sites. Clearcutting can have important effects on wildlife. However, the mechanisms by which different species are affected by clearcutting are poorly understood. Here, we performed two experiments to test whether movement behavior influences how a species responds to clearcutting at both individual (survival) and population levels (demographic change). We studied the impact of clearcutting on two rodent species in Pinus radiata plantations in south-central Chile. The study involved a very mobile (Oligorozomys longicaudatus) and a more sedentary (Abrothrix longipilis) species. To study the individual-level response to clearcutting, we radio-tracked 92 (67 A. longipilis and 25 O. longicaudatus) adult male mice from before to after clearcutting and recorded individual survival and movement. To evaluate the population-level response, we recorded the abundance for each species before (winter) and after clearcutting (spring, summer and fall). We also included abundance data in uncut mature stands (controls) to detect seasonal changes in abundance not caused by clearcutting. At the individual-level, we found that after clearcutting >80% of O. longicaudatus remained alive, while only 48% of A. longipilis survived. All A. longipilis that survived clearcutting stayed in the stand ("refuge response"), whereas 77% of O. longicaudatus evacuated the stand and relocated to undisturbed sites ("evacuate response") allowing them to survive in neighboring areas. At the population-level, the abundance of A. longipilis showed a significant decline after clearcutting that continued towards spring and summer, but in fall we found no differences between clear-cut and uncut mature stands. O. longicaudatus tended to decrease toward spring and summer in both harvested and uncut mature stands, but this trend was not significant. The abundance increased significantly in fall, where the increase in abundance in harvested stands was significantly higher than in uncut mature stands. Our results demonstrate that the short-term effects of clearcutting on abundant small mammal species are species-specific and strongly dependent on the species' movement behavior. Additionally, they showed a rapid population recovery (around 1 year) after high mortality by clearcutting over the less mobile species. [ABSTRACT FROM AUTHOR]

• Tasmanian subspecies of E. delegatensis recovers from fire by epicormic resprouts. • By contrast, the mainland Australian subspecies is a post-fire obligate seeder. • Tasmanian subspecies has greater resilience to fire than mainland subspecies. • Stems < 20-cm diameter of the Tasmanian subspecies are vulnerable to fire kill. • Risk of regeneration failure for several decades in clear-felled Tasmanian forests. Eucalyptus delegatensis is native to the Australian Alps (subsp. delegatensis) and montane Tasmania (subsp. tasmaniensis). Post-fire regeneration mechanisms of the obligate-seeder subspecies on the Australian mainland are well-known, but less is known about the resprouter Tasmanian subspecies. In January 2016, large tracts of Eucalyptus delegatensis forests in central Tasmania, logged at different intensities, were burnt by low- and high-severity fire. We used statistical modelling to understand how tree survival, vegetative regeneration and seedling recruitment differed according to understorey type, fire severity, logging intensity and tree size (DBH). Fire severity, defined as unburnt, low-severity (fire scarring on the stem and/or lower canopy burnt) and high-severity (full canopy burnt), affected tree survival: 84% of trees were alive in unburnt transects, compared with 43% in low-severity transects and 36% in high-severity transects. Epicormic resprouting was the dominant mode of vegetative recovery, with < 1% of total trees recovering solely by basal resprouting. Fire severity significantly affected epicormic resprouting, with 70% of live stems resprouting post-fire in low-severity transects and 99% in high-severity transects, compared with 4% in unburnt transects. Tree survival was strongly influenced by tree size: in high-severity transects, 24% of trees with DBH < 20 cm were alive, compared with 88% of trees with DBH ≥ 20 cm. These differences in survival were primarily because large trees were more likely to resprout epicormically, with epicormic shoots present on 24% of live trees with DBH < 20 cm, compared with 79% of live trees with DBH ≥ 80 cm. The strong effect of tree size renders clear-felled forests especially vulnerable to fire during the several decades when all the regenerating trees are small (DBH < 20 cm). Seedling recruitment was uncommon, independent of understorey type and logging intensity, but with higher occurrence on high-severity (54%) than low-severity (19%) or unburnt (15%) transects. When present, seedling densities were typically low: median = 400 and maximum = 4·104 seedlings ha−1. This study highlights that mature forests of Eucalyptus delegatensis in Tasmania are more resilient (able to return to pre-disturbance conditions) to single high-severity fires than their mainland counterparts, because they can recover more quickly through epicormic resprouting. However, clear-felling reduces this resilience for several decades because it decreases median tree size and, hence, leads to higher post-fire mortality. It is difficult to predict how the Tasmanian subspecies will respond to an increased frequency of high-severity fires associated with a projected warmer and drier climate. [ABSTRACT FROM AUTHOR]

Time series of satellite sensor data have been used to quantify mangrove cover changes at regional and global levels. Although mangrove forests have been monitored using remote sensing techniques, the use of time series to quantify the regeneration of these forests still remains limited. In this study, we focus on the Matang Mangrove Forest Reserve (MMFR) located in Peninsular Malaysia, which has been under silvicultural management since 1902 and provided the opportunity to investigate the use of Landsat annual time series (1988–2015) for (i) detecting clear-felling events that take place in the reserve as part of the local management, and (ii) tracing back and quantifying the early regeneration of mangrove forest patches after clear-felling. Clear-felling events were detected for each year using the Normalized Difference Moisture Index (NDMI) derived from single date (cloud-free) or multi-date composites of Landsat sensor data. From this series, we found that the average period for the NDMI to recover to values observed prior to the clear-felling event between 1988 and 2015 was 5.9 ± 2.7 years. The maps created in this study can be used to guide the replantation strategies, the clear-felling planning, and the management and monitoring activities of the MMFR. [ABSTRACT FROM AUTHOR]

We review the consequences for biodiversity and ecosystem services from the industrial-scale extraction of logging residues (tops, branches and stumps from harvested trees and small-diameter trees from thinnings) in managed forests. Logging residue extraction can replace fossil fuels, and thus contribute to climate change mitigation. The additional biomass and nutrients removed, and soils and other structures disturbed, have several potential environmental impacts. To evaluate potential impacts on ecosystem services and biodiversity we reviewed 279 scientific papers that compared logging residue extraction with non-extraction, the majority of which were conducted in Northern Europe and North America. The weight of available evidence indicates that logging residue extraction can have significant negative effects on biodiversity, especially for species naturally adapted to sun-exposed conditions and the large amounts of dead wood that are created by large-scaled forest disturbances. Slash extraction may also pose risks for future biomass production itself, due to the associated loss of nutrients. For water quality, reindeer herding, mammalian game species, berries, and natural heritage the results were complicated by primarily negative but some positive effects, while for recreation and pest control positive effects were more consistent. Further, there are initial negative effects on carbon storage, but these effects are transient and carbon stocks are mostly restored over decadal time perspectives. We summarize ways of decreasing some of the negative effects of logging residue extraction on specific ecosystem services, by changing the categories of residue extracted, and site or forest type targeted for extraction. However, we found that suggested pathways for minimizing adverse outcomes were often in conflict among the ecosystem services assessed. Compensatory measures for logging residue extraction may also be used (e.g. ash recycling, liming, fertilization), though these may also be associated with adverse environmental impacts., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)