Boreal tree species change as a climate mitigation strategy: impact on ecosystem C and N stocks and soil nutrient levels

As tree species composition in forests of the northeastern United States changes due to invasive forest pests, climate change, or other stressors, the extent to which forests will retain or release N from atmospheric deposition remains uncertain. We used a species-specific, dynamic forest ecosystem model (Spe-CN) to investigate how nitrate (NO3–) leaching may vary among stands dominated by different species, receiving varied atmospheric N inputs, or undergoing species change due to an invasive forest pest (emerald ash borer; EAB). In model simulations, NO3– leaching varied widely among stands dominated by 12 northeastern North American tree species. Nitrate leaching increased with N deposition or forest age, generally with greater magnitude for deciduous (except red oak) than coniferous species. Species with lowest baseline leaching rates (e.g., red spruce, eastern hemlock, red oak) showed threshold responses to N deposition. EAB effects on leaching depended on the species replacing white ash: after 100 years, predicted leaching increased 73% if sugar maple replaced ash but decreased 55% if red oak replaced ash. This analysis suggests that the effects of tree species change on NO3– leaching over time may be large and variable and should be incorporated into predictions of effects of N deposition on leaching from forested landscapes.

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The Paradox of Climate Change Mitigation and Adaptation in Danish Housing

Open House International ◽

10.1108/ohi-04-2012-b0003 ◽

2012 ◽

Vol 37 (4) ◽

pp. 19-28

Author(s):

Rob Marsh

Keyword(s):

Climate Change ◽

Energy Consumption ◽

Solar Energy ◽

Theoretical Study ◽

Climate Adaptation ◽

Mitigation Strategy ◽

Mitigation Strategies ◽

Space Heating ◽

Climate Mitigation ◽

Passive Solar

Climate change means that buildings must greatly reduce their energy consumption. It is however paradoxical that climate mitigation in Denmark has created negative energy and indoor climate problems in housing that may be made worse by climate change. A literature review has been carried out of housing schemes where climate mitigation was sought through reduced space heating demand, and it is shown that extensive problems with overheating exist. A theoretical study of regulative and design strategies for climate mitigation in new build housing has therefore been carried out, and it is shown that reducing space heating with high levels of thermal insulation and passive solar energy results in overheating and a growing demand for cooling. Climate change is expected to reduce space heating and increase cooling demand in housing. An analysis of new build housing using passive solar energy as a climate mitigation strategy has therefore been carried out in relation to future climate change scenarios. It is shown that severe indoor comfort problems can occur, questioning the relevance of passive solar energy as a climate mitigation strategy. In conclusion, a theoretical study of the interplay between climate adaptation and mitigation strategies is carried out, with a cross-disciplinary focus on users, passive design and active technologies. It is shown that the cumulative use of these strategies can create an adaptation buffer, thus eliminating problems with overheating and reducing energy consumption. New build housing should therefore be designed in relation to both current and future climate scenarios to show that the climate mitigation strategies ensure climate adaptation.

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Soil carbon debt of 12,000 years of human land use

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1706103114 ◽

2017 ◽

Vol 114 (36) ◽

pp. 9575-9580 ◽

Cited By ~ 186

Author(s):

Jonathan Sanderman ◽

Tomislav Hengl ◽

Gregory J. Fiske

Keyword(s):

Land Use ◽

Carbon Balance ◽

Mitigation Strategy ◽

Global Environment ◽

Climate Mitigation ◽

Grazing Land ◽

The Past ◽

Human Land Use ◽

History Database ◽

Global Carbon

Human appropriation of land for agriculture has greatly altered the terrestrial carbon balance, creating a large but uncertain carbon debt in soils. Estimating the size and spatial distribution of soil organic carbon (SOC) loss due to land use and land cover change has been difficult but is a critical step in understanding whether SOC sequestration can be an effective climate mitigation strategy. In this study, a machine learning-based model was fitted using a global compilation of SOC data and the History Database of the Global Environment (HYDE) land use data in combination with climatic, landform and lithology covariates. Model results compared favorably with a global compilation of paired plot studies. Projection of this model onto a world without agriculture indicated a global carbon debt due to agriculture of 133 Pg C for the top 2 m of soil, with the rate of loss increasing dramatically in the past 200 years. The HYDE classes “grazing” and “cropland” contributed nearly equally to the loss of SOC. There were higher percent SOC losses on cropland but since more than twice as much land is grazed, slightly higher total losses were found from grazing land. Important spatial patterns of SOC loss were found: Hotspots of SOC loss coincided with some major cropping regions as well as semiarid grazing regions, while other major agricultural zones showed small losses and even net gains in SOC. This analysis has demonstrated that there are identifiable regions which can be targeted for SOC restoration efforts.

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The Environmental Relations of Vegetation Pattern on Chenier Beach Ridges on Bathurst Island, Northern Territory

Australian Journal of Botany ◽

10.1071/bt9930275 ◽

1993 ◽

Vol 41 (3) ◽

pp. 275 ◽

Cited By ~ 2

Author(s):

RJ Fensham

Keyword(s):

Sea Water ◽

Acid Soils ◽

Soil Nutrient ◽

Vegetation Pattern ◽

High Concentration ◽

Radiocarbon Dates ◽

Beach Ridges ◽

Nutrient Levels ◽

Environmental Relations ◽

Monsoon Rainforest

Radiocarbon dates confirm a chronological sequence for late Holocene beach ridges at Wangiti Beach on Bathurst Island. The vegetation on these beach ridges can be clearly related to topography and distance from the sea. Monsoon rainforest occurs on the fore-dunes where the nutrient levels of the young sediments are relatively high. The mid-dunes support woodland dominated by Melalueca viridiflora and have nutrient-poor acid soils. Vegetation with a high component of monsoon rainforest species occupies the rear dunes, which have a high concentration of seawater macronutrient cations despite their older age than more seaward dunes. The relatively low elevation of the rear dunes supports the suggestion that soil nutrient levels are enriched by sea water or marine sediments during infrequent inundation events such as those during cyclones.

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Metagenomic reconstruction of nitrogen and carbon cycling pathways in forest soil: Influence by different hardwood tree species

10.1101/2020.06.23.167700 ◽

2020 ◽

Author(s):

Charlene N. Kelly ◽

Geoffrey W. Schwaner ◽

Jonathan R. Cumming ◽

Timothy P. Driscoll

Keyword(s):

Tree Species ◽

Plant Litter ◽

American Chestnut ◽

Soil Microbiome ◽

Red Oak ◽

Black Cherry ◽

Soil Microbial ◽

Below Ground ◽

C And N ◽

Hardwood Tree

AbstractThe soil microbiome plays an essential role in processing and storage of nitrogen (N) and carbon (C), and is influenced by vegetation above-ground through imparted differences in chemistry, structure, mass of plant litter, root physiology, and dominant mycorrhizal associations. We used shotgun metagenomic sequencing and bioinformatic analysis to quantify the abundance and distribution of gene families involved in soil microbial N and C cycling beneath three deciduous hardwood tree species: ectomycorrhizal (ECM)-associated Quercus rubra (red oak), ECM-associated Castanea dentata (American chestnut), and arbuscular mycorrhizal (AM)-associated Prunus serotina (black cherry). Chestnut exhibited the most distinct soil microbiome of the three species, both functionally and taxonomically, with a general suppression of functional genes in the nitrification, denitrification, and nitrate reduction pathways. These changes were related to low inorganic N availability in chestnut stands as soil was modified by poor, low-N litter quality relative to red oak and black cherry soils.IMPORTANCEPrevious studies have used field biogeochemical process rates, isotopic tracing, and targeted gene abundance measurements to study the influence of tree species on ecosystem N and C dynamics. However, these approaches do not enable a comprehensive systems-level understanding of the relationship between microbial diversity and metabolism of N and C below-ground. We analyzed microbial metagenomes from soils beneath red oak, American chestnut, and black cherry stands and showed that tree species can mediate the abundance of key microbial genes involved in N and (to a lesser extent) C metabolism pathways in soil. Our results highlight the genetic framework underlying tree species’ control over soil microbial communities, and below-ground C and N metabolism, and may enable land managers to select tree species to maximize C and N storage in soils.

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A Comprehensive Climate Mitigation Strategy for Mexico

IMF Working Papers ◽

10.5089/9781513599847.001 ◽

2021 ◽

Vol 2021 (246) ◽

pp. 1

Author(s):

Mehdi Raissi ◽

Ian Parry ◽

Koralai Kirabaeva ◽

Simon Black ◽

Karlygash Zhunussova

Keyword(s):

Mitigation Strategy ◽

Climate Mitigation

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Decades of tree planting in Northern India had little effect on forest density and rural livelihoods

10.21203/rs.3.rs-289460/v1 ◽

2021 ◽

Author(s):

Eric Coleman ◽

Bill Schultz ◽

Vijay Ramprasad ◽

Harry Fischer ◽

Pushpendra Rana ◽

...

Keyword(s):

Forest Cover ◽

Rural Livelihoods ◽

Mitigation Strategy ◽

Tree Planting ◽

Climate Mitigation ◽

Forest Density ◽

Northern India ◽

Local Livelihoods ◽

Dense Forest ◽

Household Livelihood

Abstract Myriad scholars, policymakers, and practitioners advocate tree planting as a climate mitigation strategy and to support local livelihoods. But, is the broad appeal of tree planting supported by evidence? We report estimated impacts from decades of tree planting in Northern India. We find that tree plantings have not, on average, increased the proportion of dense forest cover, and have modestly shifted species composition away from the broadleaf varieties valued by local people. Supplementary analysis from household livelihood surveys show that, in contrast to narratives of forest dependent people being supported by tree planting, there are few direct users of these plantations and their dependence is low. We conclude that decades of expensive tree planting programs have not proved effective.

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