Woodland restoration on agricultural land: long-term impacts on soil quality

Woodland restoration is underway globally, to counter the negative soil quality and ecological impacts of agricultural expansion and woodland fragmentation, and restore or enhance biodiversity, ecosystem functions and services. However, we lack information about the long‐term effects of woodland restoration on agricultural soils, particularly at temporal scales meaningful to woodland and soil development. This study utilised soil and earthworm sampling across a chronosequence of sites transitioning from ‘agricultural land’ to ‘secondary woodland’ (50‐110 years) and ‘ancient woodland’ (>400 years), with the goal of quantifying the effects of woodland restoration on agricultural land, on key soil quality parameters (soil bulk density, pH, carbon and nitrogen stocks, and earthworm abundance, biomass, species richness and diversity). Broad‐leaved woodland restoration led to significantly greater soil organic carbon (SOC) stocks compared to arable land, and young (50‐60 years) secondary woodland increased earthworm species and functional diversity compared to both arable and pasture agricultural land. SOC stocks in secondary broad‐leaved woodlands (50‐110 years) were comparable to those found in long‐term ancient woodlands (>400 years). Our findings show that broad‐leaved woodland restoration of agricultural land can lead to meaningful soil ecological improvement and gains in SOC within 50 to 110 years, and provide intel on how restoration activities may be best targeted to maximise soil quality and functions

Biodiversity 2020: climate change evaluation report

In 2011, the government published Biodiversity 2020: A strategy for England’s wildlife and ecosystem services [1]. This strategy for England builds on the 2011 Natural Environment White Paper - NEWP [2] and provides a comprehensive picture of how we are implementing our international and EU commitments. It sets out the strategic direction for biodiversity policy between 2011-2020 on land (including rivers and lakes) and at sea, and forms part of the UK’s commitments under the ‘the Aichi targets’ agreed in 2010 under the United Nations Convention of Biological Diversity’s Strategic Plan for Biodiversity 2011-2020 [3]. Defra is committed to evaluating the Biodiversity 2020 strategy and has a public commitment to assess climate change adaptation measures. This document sets out the information on assessing how action under Biodiversity 2020 has helped our wildlife and ecosystems to adapt to climate change. Biodiversity 2020 aims to halt the loss of biodiversity and restore functioning ecosystems for wildlife and for people. The outcomes and actions in Biodiversity 2020, although wider in scope, aimed to increase resilience of our wildlife and ecosystems in the face of a changing climate. In order to inform the assessment, we have defined which of the measurable outputs under Biodiversity 2020 contribute to resilience. Biodiversity 2020 included plans to develop and publish a dedicated set of indicators to assess progress towards the delivery of the strategy. The latest list (at the time of writing), published in 2017, contains 24 biodiversity indicators [4] that would help inform progress towards achieving specific outcomes, they are also highly relevant to the outputs (detailed below) that form the basis for this evaluation. The Adaptation Sub-Committee’s 2017 UK Climate Change Risk Assessment Evidence Report [5] sets out the priority climate change risks and opportunities for the UK. The ASC also produced a review of progress in the National Adaptation Programme - “Progress in preparing for climate change” [6], which highlights adaptation priorities and progress being made towards achieving them. The UK Government’s response to the ASC [7] review includes a set of recommendations, of which Recommendation 6 states that “Action should be taken to enhance the condition of priority habitats and the abundance and range of priority species”. The recommendation further iterated that “This action should maintain or extend the level of ambition that was included in Biodiversity 2020” and that “An evaluation should be undertaken of Biodiversity 2020 including the extent to which goals have been met and of the implications for resilience to climate change.” To this, end an evaluation process has been put in place to define: a. What worked and why? Which actions or activities have had the greatest benefit in terms of delivering the desired outcomes? And, conversely, what prevented progress? b. Where are the opportunities? What are the financial, political, scientific and social opportunities for furthering the desired outcomes in the future? These objectives underpin the evaluation process for actions to date, and will also inform future actions and the iteration of a new nature strategy for England

Climate Change Legislation: Positive or Negative For North Dakota Agriculture?

The United States House of Representatives passed a climate change bill entitled “The American Clean Energy and Security Act” in June 2009. The bill establishes a combined efficiency and renewable electricity standard which requires retail electricity suppliers to utilize 20% renewable energy by 2020. The objective of this study is to estimate the costs of the American Clean Energy and Security Act in crop production and the benefits of carbon sequestration under the legislation. This study especially evaluates the impact of the legislation on the North Dakota farm income under a Cap and Trade system with and without carbon sequestration. Three different carbon sequestration programs are evaluated to estimate the impact of each program on the net farm income in North Dakota: no-till farming, wetlands restoration and wood land establishment. The North Dakota Representative Farm Model operational a North Dakota State University was used to estimate the impact of the Cap and Trade legislation and evaluate the impact of the various carbon sequestration programs.Carbon sequestration, American Clean Energy and Security Act, North Dakota Representative Farm model, no-till, wetlands, woodlands, net farm income, Agribusiness,

Object-based assessment of tree attributes of Acacia tortilis in Bou-Hedma, Tunisia

Acacia tortilis subsp. raddiana represents the most important woody species in the pre-Saharan zone. It is the only forest tree persisting on the edge of the desert. Due to tree/environment interactions, canopy sub-habitats arise, enabling an increased storage of soil water, soil nutrients and soil oxygen. Depending on their density, they can also reduce erosion and reverse desertification. Soil erosion and desertification are the main problems faced by the UNESCO Biosphere Reserve in South-Tunisia (Bou-Hedma National Park). The restoration of the original woodland cover to combat desertification (particularly) by afforestation and reforestation of Acacia tortilis goes hand in hand with a climate change in the Biosphere Reserve, also influencing rural population outside the Biosphere Reserve. In order to study the different effects of woodland restoration in Bou-Hedma, the number of Acacia trees and their attributes have to be known. High resolution satellite imagery (GeoEye-1), was used with a GEOBIA approach. Field measurement of bole diameter, crown diameter and tree height were collected at > 400 locations. After segmentation, correlations with > 200 object features and tree attributes were calculated. For crown diameter and tree height, high correlations were observed with the features area and GLCM Entropy Layer 4 (90 degrees). Relations between these features and measured tree attributes were modeled, resulting in RMSE values of resp. 1.47 m and 1.62 m for crown diameter estimation and 0.92 m for tree height. The results show that a GEOBIA working strategy is suitable for estimating tree attributes in open forests in semi-arid regions

Computer Modelling as an Aid to Forest and Woodland Restoration

Reclamation of terrestrial ecosystems tends to be focussed on two main land uses, mining and degraded agricultural or forested lands. Modelling has great potential to assist in both situations. The aim of many restoration programs is to restore biodiversity and a self-sustaining, fully functional ecosystem, which is intimately linked with the return of the plants, the vertebrates and, particularly, the invertebrate fauna, whose presence plays a pivotal role in most ecosystem functions and processes. A thorough understanding of these plant-fauna associations is essential if restoration is to succeed. It could also equip us with the knowledge to decide how minimalistic our information needs can be when modelling progress with restoration, for instance: by quantifying certain biophysical parameters; these plus certain vegetation indices; or by both plus a range of faunal attributes. As well as streamlining the restoration monitoring process, this could lead to the enhancement of the conservation value of the restoration, and a clear understanding of the ecological links between flora and fauna would also help develop bioindicators as components of completion criteria schedules. Using Western Australian bauxite mining in the Jarrah (Eucalyptus marginata) forest as a case study, this paper reviews rehabilitation prescriptions and trends in development of plant assemblages, invertebrate colonization and litter decomposition, and applies a systems dynamic modelling approach model to test assumptions regarding the evolution of plant-fauna assemblages in time and assess whether it is feasible to predict temporal changes in the rehabilitation of this ecosystem. Secondly, in relation to efforts to purchase and rehabilitate land to reconnect remnant woodland vegetation close to the south coast of Western Australia, network analysis and multi-level simulations are applied in order to decide the best locations to acquire land and to restore it in order to optimise connectivity

Long-term woodland restoration on lowland farmland through passive rewilding.

Natural succession of vegetation on abandoned farmland provides opportunities for passive rewilding to re-establish native woodlands, but in Western Europe the patterns and outcomes of vegetation colonisation are poorly known. We combine time series of field surveys and remote sensing (lidar and photogrammetry) to study woodland development on two farmland fields in England over 24 and 59 years respectively: the New Wilderness (2.1 ha) abandoned in 1996, and the Old Wilderness (3.9 ha) abandoned in 1961, both adjacent to ancient woodland. Woody vegetation colonisation of the New Wilderness was rapid, with 86% vegetation cover averaging 2.9 m tall after 23 years post-abandonment. The Old Wilderness had 100% woody cover averaging 13.1 m tall after 53 years, with an overstorey tree-canopy (≥ 8 m tall) covering 91%. By this stage, the structural characteristics of the Old Wilderness were approaching those of neighbouring ancient woodlands. The woody species composition of both Wildernesses differed from ancient woodland, being dominated by animal-dispersed pedunculate oak Quercus robur and berry-bearing shrubs. Tree colonisation was spatially clustered, with wind-dispersed common ash Fraxinus excelsior mostly occurring near seed sources in adjacent woodland and hedgerows, and clusters of oaks probably resulting from acorn hoarding by birds and rodents. After 24 years the density of live trees in the New Wilderness was 132/ha (57% oak), with 390/ha (52% oak) in the Old Wilderness after 59 years; deadwood accounted for 8% of tree stems in the former and 14% in the latter. Passive rewilding of these 'Wilderness' sites shows that closed-canopy woodland readily re-established on abandoned farmland close to existing woodland, it was resilient to the presence of herbivores and variable weather, and approached the height structure of older woods within approximately 50 years. This study provides valuable long-term reference data in temperate Europe, helping to inform predictions of the potential outcomes of widespread abandonment of agricultural land in this region

Avian Ecology During Oak Savanna and Woodland Restoration in the Mid-South

Disturbance-dependent ecosystems in the eastern United States have been declining since European settlement, and, in recent years, early-successional species have followed. My objective for this research was to determine if oak savanna and woodland restoration (i.e., overstory thinning and prescribed fire) was a viable method of recovering declining earlysuccessional species to the landscape of the Mid-South. At 3 sites, Catoosa Wildlife Management Area (CWMA; Tennessee), Green River Game Lands (GRGL; North Carolina), and Land Between the Lakes National Recreation Area (LBL; Tennessee), oak savanna and woodland restoration projects were established and maintained. Closed-canopy stands were thinned and a 2-year burn schedule was implemented. In Chapter One, I present on nest- and stand-level vegetation metrics associated with Prairie Warbler (Setophaga discolor) nest survival and nest-site selection at CWMA 7 years after canopy disturbance and consistent burning. In 2015 and 2016, Prairie Warblers had average nest success (0.937 ± 0.007) compared with other studies and selected for increased herbaceous groundcover around the nest compared with available habitat. Nest survival in 2015 was lower than in 2016. A positive trend between groundcover and nest survival was found. In Chapter Two, I describe nest- and stand-level vegetation metrics associated with Red-headed Woodpecker (Melanerpes erythrocephalus) nest survival and nest-site selection at CWMA 7 years after canopy disturbance and consistent burning. Red-headed Woodpeckers had very high nest success (84.1%) compared with other studies and selected nest sites with greater herbaceous groundcover, dead basal area, and midstory density (in 2016) compared with available habitat. A negative trend was found between nest survival and live basal area. In Chapter Three, I describe vegetation metrics (herbaceous groundcover, live and dead basal area, and midstory density) influencing 28 bird species’ abundances at CWMA, GRGL, and LBL 2010–2012 and 2014–2016. Moderate to high amounts of disturbance were associated with increased populations of early-successional species while low to moderate amounts of disturbance either did not affect or were positively associated with populations of most mature forest species. Oak savanna and woodland restoration is a viable method to increase populations of early-successional bird species while retaining most mature forest species

300,000 Hectares Restored in Shinyanga, Tanzania — but what did it really take to achieve this restoration?

This paper presents ecosystem (Miombo and Acacia woodland) restoration that has taken place in Shinyanga, Tanzania since 1985. Prior to 1985, the region had been degraded of its Acacia and Miombo woodlands (as part of tsetse fly eradication and cash crop based agricultural expansion). As a result, these two ecosystems nearly collapsed. By 2004, more than 300,000 ha of woodland had been restored across the 833 villages of the region with an economic value of US$14 per person per month. Nearly every family had their own restored patch of woodland, while groups and villages had much larger areas of restored woodlands. While the details of this large scale ecosystem restoration are reasonably well known, the underlying reasons for the success of the restoration are less well known. They go way beyond the technicalities of ecosystem restoration. The case study explores how issues of personalities, enabling policy, decentralized and participatory governance, gender, traditional knowledge and institutions, contribute to woodland restoration (where all scales count — from small family forests to larger village forests). Both the more technical aspects of ecosystem restoration and all the socio-political aspects were central to this success. However even these issues are part of ongoing processes of negotiating and re-negotiating local level governance and management arrangements. Overall the combination of the ecosystem restoration and governance arrangement resulted in more resilient communities, land use and ecosystems

Patterns and Drivers of Wiregrass Gap Longleaf Pine (Pinus palustris Mill.) Woodland Succession as Part of Restoration Efforts

Longleaf Pine (Pinus palustris) communities are widespread throughout the Southeastern United States with a dominant understory vegetation of wiregrass (Aristida spp.) in most of its range. A small area in central South Carolina that is naturally free of wiregrass is called the “Wiregrass Gap”. Here, the understory vegetation is dominated by bluestems grasses (Andropogon spp. and Schizachyrium spp.) which drive the disturbance regime of frequent low-intensity fire. The successful establishment of these grasses is key for longleaf pine woodland restoration efforts in this region, but few resources detail the ecological drivers at play that enable successful restoration in these longleaf pine woodlands. I investigated these drivers of succession through the lens of slash manipulation treatments that resulted from a restoration harvest. Exposed duff and mineral soil had a favorable effect on the herbaceous response but also benefitted the regeneration of many loblolly pine seedlings. This complicates restoration efforts. An abundance of woody material was suspected as a suppressant of establishing vegetation. In addition, I investigated how early successional plants can contribute to the restoration process. By quickly establishing in soil devoid of arbuscular mycorrhizal fungi that are vital for plant growth, early successional plants can enhance the arbuscular mycorrhizal inoculum in the soil and successfully preconditioning it for the benefit of later successional plants as they colonize the site. The restoration of Wiregrass Gap longleaf pine communities is thus adaptable to different induced and ecological drivers that together can result in successful woodland restoration

The benefits of mountain woodland restoration

Mountain woodland ecotones require urgent action to reverse long-term habitat degradation and biodiversity loss. There is growing interest in restoring high-elevation woodland and scrub communities, harnessing planting and natural regeneration. Emissions offsetting has been a key driver, yet mountain systems offer slower mechanisms for biomass accumulation due to their typically smaller size, lower density and slower growth than forests at lower elevations. We argue that the natural capital afforded by mountain woodland restoration is far more comprehensive than carbon sequestration alone and encompasses an important array of ecosystem services and biodiversity gains. Improved opportunities for wildlife and people include natural hazard protection, sheltering, structural variability, vegetation diversity and recreation. Furthermore, mountain woodland restoration provides critically needed nature- based solutions for reducing threats from escalating climate change such as soil erosion, flooding, warming temperatures and extreme weather. It is imperative that these benefits are embedded within conservation policy and environmental incentives.Output Status: Forthcoming/Available Onlin