Forest cover estimation in Ireland using radar remote sensing: a comparative analysis of forest cover assessment methodologies

Quantification of spatial and temporal changes in forest cover is an essential component of forest monitoring programs. Due to its cloud free capability, Synthetic Aperture Radar (SAR) is an ideal source of information on forest dynamics in countries with near-constant cloud-cover. However, few studies have investigated the use of SAR for forest cover estimation in landscapes with highly sparse and fragmented forest cover. In this study, the potential use of L-band SAR for forest cover estimation in two regions (Longford and Sligo) in Ireland is investigated and compared to forest cover estimates derived from three national (Forestry2010, Prime2, National Forest Inventory), one pan-European (Forest Map 2006) and one global forest cover (Global Forest Change) product. Two machine-learning approaches (Random Forests and Extremely Randomised Trees) are evaluated. Both Random Forests and Extremely Randomised Trees classification accuracies were high (98.1–98.5%), with differences between the two classifiers being minimal (<0.5%). Increasing levels of post classification filtering led to a decrease in estimated forest area and an increase in overall accuracy of SAR-derived forest cover maps. All forest cover products were evaluated using an independent validation dataset. For the Longford region, the highest overall accuracy was recorded with the Forestry2010 dataset (97.42%) whereas in Sligo, highest overall accuracy was obtained for the Prime2 dataset (97.43%), although accuracies of SAR-derived forest maps were comparable. Our findings indicate that spaceborne radar could aid inventories in regions with low levels of forest cover in fragmented landscapes. The reduced accuracies observed for the global and pan-continental forest cover maps in comparison to national and SAR-derived forest maps indicate that caution should be exercised when applying these datasets for national reporting

Contemporary forest loss in Ireland; quantifying rare deforestation events in a fragmented forest landscape

Accurate quantification of forest loss is required to meet international reporting requirements, even in countries where deforestation rates are low. In Ireland, recent evidence has suggested the rate of gross annual deforestation is increasing. However, no spatially explicit data on the extent and character of contemporary deforestation exists. Here, we quantify deforestation in a region where forest loss is rare. Deforestation estimates derived from wall-to-wall photointerpretation, official records (e.g. felling licences), the CORINE land-use/land cover changes dataset and a combined approach (hereafter termed “the Deforestation Map”) are compared in two regions in Ireland for the period 2000 to 2012. Deforestation area based on the Deforestation Map (1497 ha) was greater than estimates derived from using photo-interpretation (730 ha), official records (908 ha) and CORINE (139 ha) alone. Independent accuracy assessment highlighted high errors of omission for photo-interpretation (68.9%), official records (66.7%) and CORINE (91.84%) estimates compared to the Deforestation Map (20%). No general increase in the deforestation rate during the study period was recorded, despite regional variations. Post deforestation land-use transitions were principally to wetland, grassland and settlement although the magnitude and proportion of change varied regionally. Gross annual deforestation was higher in older broadleaf forests than in conifer plantation forests, a surprising finding considering the small area and conservation status of many broadleaf forests in Ireland. For countries with small forest area and/or low rates of deforestation, the use of methodologies employed herein can provide a valuable record of forest loss and be used to validate sample-based or remotely sensed deforestation estimates

Deforestation in Ireland 2000 – 2012

Although Ireland’s national forest area continues to expand, recent evidence has suggested that the gross annual rate of deforestation is also increasing. Heretofore, no spatially explicit characterisation of contemporary deforestation areas in Ireland exists. Given uncertainties associated with current deforestation estimates, investigation of new methodologies is required to inform future land-use change accounting approaches. This paper presents a summary of the DEFORMAP project, which investigated the extent and nature of deforestation in Ireland for the 2000 – 2012 period. A combination of high resolution aerial photography, satellite imagery and ancillary datasets was used to quantify forest loss in the Republic of Ireland. In total, 5,457 ha of deforested land was identified which, following accuracy assessment, was error-adjusted to 7,465 ±785 ha. The error-adjusted gross annual national deforestation rate for the period of study was 0.103%. The deforestation rate increased from the first time interval investigated (2000-2005) to the second (2005-2010), followed by a reduction during the 2010 – 2012 period. High inter-county variation in gross annual deforestation was identified, with the highest level of deforestation occurring in Co. Monaghan (0.25% yr-1) and the lowest in Co. Limerick (0.02% yr-1). Principal post-deforestation land-use transitions were to agricultural grassland, built-land and wetland. Patterns of post-deforestation land-use transitions varied widely between counties indicating changing regional pressures on forest land. This paper presents an important development in our understanding of contemporary land-use change in Ireland by developing the first national deforestation map. The Deforestation Map presented here will provide a valuable record of forest loss, which can be used to validate any future earth observation based deforestation monitoring approaches, such as automated radar remote sensing techniques

Early Surgical Morbidity and Mortality in Adults with Congenital Heart Disease: The University of Michigan Experience

Objectives.  To review early surgical outcomes in a contemporary series of adults with congenital heart disease (CHD) undergoing cardiac operations at the University of Michigan, and to investigate possible preoperative and intraoperative risk factors for morbidity and mortality. Methods.  A retrospective medical record review was performed for all patients ≥18 years of age who underwent open heart operations by a pediatric cardiothoracic surgeon at the University of Michigan Congenital Heart Center between January 1, 1998 and December 31, 2004. Records from a cohort of pediatric patients ages 1–17 years were matched to a subset of the adult patients by surgical procedure and date of operation. Results.  In total, 243 cardiac surgical operations were performed in 234 adult patients with CHD. Overall mortality was 4.7% (11/234). The incidence of major postoperative complications was 10% (23/234) with a 19% (45/23) minor complication rate. The most common postoperative complication was atrial arrhythmias in 10.8% (25/234). The presence of preoperative lung or liver disease, prolonged cardiopulmonary bypass and aortic cross clamp times, and postoperative elevated inotropic score and serum lactates were significant predictors of mortality in adults. There was no difference between the adult and pediatric cohorts in terms of mortality and morbidity. Conclusions.  The postoperative course in adults following surgery for CHD is generally uncomplicated and early survival should be expected. Certain risk factors for increased mortality in this patient population may include preoperative presence of chronic lung or liver dysfunction, prolonged cardiopulmonary bypass and aortic cross-clamp times, and postoperative elevated inotropic score and serum lactate levels.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75596/1/j.1747-0803.2008.00170.x.pd

Mangrove microclimates alter seedling dynamics at the range edge

Recent climate warming has led to asynchronous species migrations, with major consequences for ecosystems worldwide. In woody communities, localized microclimates have the potential to create feedback mechanisms that can alter the rate of species range shifts attributed to macroclimate drivers alone. Mangrove encroachment into saltmarsh in many areas is driven by a reduction in freeze events, and this encroachment can further modify local climate, but the subsequent impacts on mangrove seedling dynamics are unknown. We monitored microclimate conditions beneath mangrove canopies and adjacent open saltmarsh at a freeze-sensitive mangrove-saltmarsh ecotone and assessed survival of experimentally transplanted mangrove seedlings. Mangrove canopies buffered night time cooling during the winter, leading to interspecific differences in freeze damage on mangrove seedlings. However, mangrove canopies also altered biotic interactions. Herbivore damage was higher under canopies, leading to greater mangrove seedling mortality beneath canopies relative to saltmarsh. While warming-induced expansion of mangroves can lead to positive microclimate feedbacks, simultaneous fluctuations in biotic drivers can also alter seedling dynamics. Thus, climate change can drive divergent feedback mechanisms through both abiotic and biotic channels, highlighting the importance of vegetation-microclimate interactions as important moderators of climate driven range shifts

Spatial patterns of natural regeneration in stands of English yew (Taxus baccata L.); Negative neighbourhood effects

Understanding the mechanisms underlying spatial patterns of regeneration of tree species can improve the effectiveness of forest management and restoration activities. English yew (Taxus baccata L.) stands have declined across their native range and yew dominated woodlands have priority status under the EU Habitats Directive. Several conservation and restoration programmes for this species have been established. We investigated population structure and spatial distribution of natural regeneration of yew at six woodlands in the south and west of Ireland. Specifically, the influence of adult conspecific neighbourhood density, canopy cover and distance from seed source on regeneration was explored. Within each site, canopy openness, soil and vegetation characteristics were established. Weiner spatial analysis revealed that the density of conspecific adults was negatively related to the recruitment of yew juveniles. In addition, a significant negative relationship between presence of conspecific canopy cover and regeneration density was evident. Although seedlings and saplings were scarce directly beneath conspecifics, regeneration was highest in nearby areas suggesting that intermediate dispersal distance maximises recruitment probability. Yew regeneration was correlated with a number of habitat characteristics, particularly percentage cover of woody shrubs. Management operations should focus on regeneration around the edges of populations to conserve existing yew stand

Light responses of yew (Taxus baccata L.); does size matter?

Key message Photosynthetic capacity of yew needles depends primarily on light environment, with little evidence that developmental stage is a determinant photosynthetic performance. However, needle morphology is mostly determined by plant size. Abstract Populations of yew Taxus baccata are often characterized by a lack of natural regeneration and stands of this species have been afforded priority conservation status within the European Union. Light availability is known to be a key factor influencing recruitment dynamics in yew. To explore potential size-related responses to light, we investigated the distribution, photosynthetic efficiency and needle morphological traits in yew across a gradient of light availability at Atlantic oak woodland in southwest Ireland. Young plants were more common in shaded areas whereas saplings and juvenile yews were distributed in areas of higher light availability. Photosynthetic capacity of yew needles was found to depend primarily on light environment, with little evidence that the developmental stage is a determinant of photosynthetic performance. Photoinhibition was evident in needles sampled from high light environments across all demographic size classes. However, larger plants also showed particularly strong needle morphological responses (needle length, width, thickness, and specific leaf area) to light levels, which were mostly lacking in seedlings. We conclude that there is a dual control of yew light responses; the efficiency of the photosynthetic light reactions is largely linked to the light environment in which the plants grew, while needle morphology is mostly determined by the size of the plants. The findings of this study highlight the importance of considering all life-history stages and multiple traits when evaluating species response to light availability

Conspecific negative density dependence in a long-lived conifer, yew Taxus baccata L.

Conspecific negative density dependence in tree species can have major consequences for structuring of communities, yet in temperate forests this phenomenon remains largely unexplored. We investigated density-dependent recruitment in the long-lived conifer yew (Taxus baccata L.), for which low levels of regeneration have been linked with reduced light availability beneath conspecific canopies and speculative autotoxic effects. We combined in situ assessment of yew regeneration in a temperate forest in southwest Ireland with ex situ pot experiments to assess whether light and/or beneath conspecific canopy conditions inhibit the germination and early growth of yew. In field experiments, recruitment was related to distance from adult conspecifics, with higher levels of regeneration found in areas not beneath yew canopies. However, reduced light availability beneath the dense yew canopy was not responsible for this pattern, with abundant seedlings found in areas of equivalent or even lower light availability. Pot experiments showed that seedling survival was highest in deep shade treatments. Experiments also demonstrated that the addition of yew needles negatively affected seedling growth, but not seed germination. Together, our results suggest that under natural forest conditions, the absence of regeneration beneath mature yew canopies, often attributed to low light availability, may at least be partly related to substances in yew canopy or leaf leachates

Differential effects of biological invasions on coastal blue carbon: A global review and meta‐analysis

Human‐caused shifts in carbon (C) cycling and biotic exchange are defining characteristics of the Anthropocene. In marine systems, saltmarsh, seagrass, and mangrove habitats—collectively known as “blue carbon” and coastal vegetated habitats (CVHs) —are a leading sequester of global C and increasingly impacted by exotic species invasions. There is growing interest in the effect of invasion by a diverse pool of exotic species on C storage and the implications for ecosystem‐based management of these systems. In a global meta‐analysis, we synthesized data from 104 papers that provided 345 comparisons of habitat‐level response (plant and soil C storage) from paired invaded and uninvaded sites. We found an overall net effect of significantly higher C pools in invaded CVHs amounting to 40% (±16%) higher C storage than uninvaded habitat, but effects differed among types of invaders. Elevated C storage was driven by blue C‐forming plant invaders (saltmarsh grasses, seagrasses, and mangrove trees) that intensify biomass per unit area, extend and elevate coastal wetlands, and convert coastal mudflats into C‐rich vegetated habitat. Introduced animal and structurally distinct primary producers had significant negative effects on C pools, driven by herbivory, trampling, and native species displacement. The role of invasion manifested differently among habitat types, with significant C storage increases in saltmarshes, decreases in seagrass, and no significant effect in mangroves. There were also counter‐directional effects by the same species in different systems or locations, which underscores the importance of combining data mining with analyses of mean effect sizes in meta‐analyses. Our study provides a quantitative basis for understanding differential effects of invasion on blue C habitats and will inform conservation strategies that need to balance management decisions involving invasion, C storage, and a range of other marine biodiversity and habitat functions in these coastal systems

Protocol for the RELATE trial:A feasibility and pilot randomised controlled trial of a low-intensity group intervention for young people in care with elevated posttraumatic stress symptoms

Introduction: Young people in out-of-home care have often experienced trauma, such as direct maltreatment or witnessing violence. There is good evidence that rates of mental health difficulties are high in this group, including posttraumatic stress disorder (PTSD), a trauma-specific mental health outcome. There remains less evidence to guide how to effectively address elevated PTSD symptoms (PTSS) in these young people, particularly in ways that are feasible and scalable for stretched social-care and mental health services. Methods and analysis: This protocol describes a feasibility study comprising a pilot two-arm randomised controlled trial (RCT). Participants (N = 50) will be randomised to either (a) a group-based trauma-focused programme (Teaching Recovery Techniques), delivered by mental health practitioners both online and in-person, or (b) care-as-usual. Primarily, the trial aims to explore the key feasibility and protocol acceptability questions, including rates of recruitment and retention, as well as the acceptability of the intervention (particularly the online delivery format) to participants and services. In addition, outcomes including PTSS (primary clinical outcome), depression and functioning will be assessed at baseline (pre-randomisation), post-intervention and at a 3-month follow-up. Ethics and dissemination: Ethical approval has been received from the Health Research Authority (Wales REC1 Ref 20/WA/0100) and University, with further approval from the host trust and social care site. The results will inform the design of a definitive RCT. Dissemination will include peer-reviewed journal articles reporting the qualitative and quantitative results, as well as presentations at conferences and lay summaries. Trial registration: ClinicalTrials.gov, NCT04467320. Registered on 13 July 2020