Forest innovation to tackle the climate and biodiversity emergencies

Overview • Planting mixed woodland enhances tree growth and productivity. Mixed woodland plantations should, therefore, play a key role enabling the UK to meet its 2050 net zero greenhouse gas emissions targets. • Elevated atmospheric CO2 concentrations (eCO2) increase photosynthesis, which is necessary (but not in itself sufficient) for increased carbon storage in forests. Remote sensing data have revealed an increased greening of the earth over the last 20 years that is largely due to greater leaf area in forests. Such findings demonstrate that UK forests are effective in carbon uptake in the future, as well as improving soil health. • Undisturbed forests eventually reach carbon balance. They may continue to provide long-term carbon draw-down and storage by building ‘recalcitrant’ soil carbon. To secure and enhance long-term draw-down and storage in the forest canopy above ground, wood products must be taken from the forest and stored long term. Hence, woodland planning must incorporate harvesting for timber and other wood products in order to contribute to long-term carbon budgeting, biodiversity enhancement, and the delivery of societal benefits. • Current afforestation and forest management regulations and guidelines are innovation-averse and highly vulnerable to globalised disease and climate risks. Neither the Nature for Climate Fund1, nor the ongoing series of UK Carbon Budgets2, provide the space for innovation to manage these risks. • Private actors are pathfinding recolonisation and silvicultural portfolio approaches to increase resilience and manage social risks such as ‘carbon colonialism’. • Choosing forest-facing post-16, apprenticeship, and degree training is a direct route to climate action for UK school leavers but this case is not being made to them. • Forest-facing education is tarnished by outmoded and educationally indefensible caricatures of practice-based learning (cf. medicine or veterinary science), severely hindering One Health responses to the climate and nature emergencies and the pandemic. • The benefits of woodland creation are inherently context-dependent, and sensitive to what tree species are used. For example, as sources of nitrogen pollution come under control in the UK, adding nitrogen fixing tree species will enhance woodland carbon sequestration rates under most circumstances

Ice sheet advance, dynamics, and decay configurations : evidence from West Central Scotland

A 3700-km2 area adjacent to the Firth of Clyde, Scotland, is examined to constrain the development and dynamics of the western central sector of the last British and Irish Ice Sheet. Results from geomorphological mapping, lithostratigraphic investigations, three-dimensional geological modelling and field observations are combined to produce an empirically constrained, five-stage conceptual model of ice sheet evolution. (A) Previously published dates on interstadial organic deposits and mammalian fossils suggest that the Main Late Devensian (MLD) (MIS 2) glaciation of central Scotland began after 35 ka cal BP. During build-up, ice advanced from the western Scottish Highlands into the Clyde and Ayrshire basins. Glaciomarine muds and shelly deposits scavenged from the Firth of Clyde were redeposited widely as shelly tills and glacial rafts. Ice advance against reverse slopes generated, and subsequently overtopped, ice-marginal sediment accumulations. We hypothesise that some of these formed pre-cursor ridges which were moulded into suites of ribbed moraine during the glacial cycle. (B) Sustained stadial conditions at the Last Glacial Maximum (LGM) (c 30–25 ka cal BP) resulted in development of a major dispersal centre over the Firth of Clyde and Southern Uplands. This dispersal centre locally preserved previously formed subglacial bedforms, and fed a wide corridor of fast-flowing ice east towards the Firth of Forth. (C) Initial deglaciation promoted a substantial re-configuration of the ice surface, with enhanced westward drawdown into the outer Firth of Clyde and eastward migration of an ice divide towards the Clyde-Forth watershed. (D) Renewed ice sheet thickening over the Firth of Clyde may have accompanied growth of the Irish Ice Sheet during the Killard Point Stadial (c 17.1–15.2 ka cal BP); it was associated with limited bed modification. Subsequent ice sheet retreat was characterised by substantial meltwater production, ponding and erosion. (E) Late stages of MLD ice sheet retreat were punctuated by one or more significant ice margin oscillations. Discovery of De Geer moraines at the site of a former proglacial lake in western Ayrshire allows glacier flow at the ice margin to be approximated as ≤290 m a−1 during one such oscillation. Such velocities were probably enabled by basal sliding and shallow sediment deformation. At this stage those parts of the MLD ice sheet margin that were grounded in the Firth of Clyde were extremely vulnerable to collapse. Final disintegration of glacier ice in the Clyde basin probably occurred early in the Lateglacial Interstadial (Greenland Interstadial-1), coinciding with marine incursion to c 40 m above present day sea level

Exploring controls of the early and stepped deglaciation on the western margin of the British Irish Ice Sheet

New optically stimulated luminescence dating and Bayesian models integrating all legacy and BRITICE-CHRONO geochronology facilitated exploration of the controls on the deglaciation of two former sectors of the British–Irish Ice Sheet, the Donegal Bay (DBIS) and Malin Sea ice-streams (MSIS). Shelf-edge glaciation occurred ~27 ka, before the global Last Glacial Maximum, and shelf-wide retreat began 26–26.5 ka at a rate of ~18.7–20.7 m a–1. MSIS grounding zone wedges and DBIS recessional moraines show episodic retreat punctuated by prolonged still-stands. By ~23–22 ka the outer shelf (~25 000 km2) was free of grounded ice. After this time, MSIS retreat was faster (~20 m a–1 vs. ~2–6 m a–1 of DBIS). Separation of Irish and Scottish ice sources occurred ~20–19.5 ka, leaving an autonomous Donegal ice dome. Inner Malin shelf deglaciation followed the submarine troughs reaching the Hebridean coast ~19 ka. DBIS retreat formed the extensive complex of moraines in outer Donegal Bay at 20.5–19 ka. DBIS retreated on land by ~17–16 ka. Isolated ice caps in Scotland and Ireland persisted until ~14.5 ka. Early retreat of this marine-terminating margin is best explained by local ice loading increasing water depths and promoting calving ice losses rather than by changes in global temperatures. Topographical controls governed the differences between the ice-stream retreat from mid-shelf to the coast