Introduction

The UK has committed to a reduction in greenhouse gas (GHG) emissions by 80% (from the 1990 baseline) by 2050 (Climate Change Act, 2008).

Attainment of this goal will require that all sectors of British industry search for sensible and meaningful approaches to reducing emissions and improving

net carbon (C) sequestration in terrestrial bodies. Forests and woodlands are a key component of the global C cycle, and their effective management at

global and regional scales is an important mechanism for reducing atmospheric GHG concentrations. Slight changes in the soil C could have a large

impact on the overall GHG balance and would affect the climate change mitigation forest could provide.

Rationale

This project will improve our knowledge of how forest management that considers the soil C pool can help combat climate change. The impact of this

work will be on policymakers, enabling them to target forest management regulation and/or incentives, and practitioners benefiting from guidelines and

advice on management actions that will protect and enhance the soil C in their forests.

FFF

This PhD is funded by the University of Cumbria (in collaboration with Forest Research)

FOREST MANAGEMENT AND BELOW-GROUND LITTER: CARBON DYNAMICS OF UK FOREST SOILS

Aims and objectives

The aim of this study is to investigate the effect

of a number of forest management practices

on forest soil C pools and nutrient content.

The objectives are to quantify differences:

1. Between Ancient Semi-Natural Woodland

(ASNW) and Plantation on Ancient

Woodland Sites (PAWS).

2. Between Clearfelling and Replanting (C&R)

and Continuous Cover Forestry (CCF).

3. Between Conventionally Harvested(CH)

and Whole-Tree Harvesting (WTH) sites.

The major part of C flow into forest soil consists

of continually renewed fine roots, which are

also returned to the soil on relatively short time

scales (Sariyildiz, 2015).

The project will include the study of root litter

quality, quantity and decomposition rates

across forest ecosystems and environmental

gradients.

Mauro Lanfranchi 1514738 – National School of Forestry, University of Cumbria 19th May 2016

PAWS

Planted forests of native or non-native tree

species that have replaced the original

‘natural’ woods on sites with a long history of

woodland cover.

Clearfell (system)

The stand overstorey is generally removed in

one harvest. New even-aged stands are

regenerated after harvest within the previously

cleared block.

WTH

The removal from a felled site of every part of

the above-ground tree, except the stump.

CCF

The use of silvicultural systems whereby the

forest canopy is maintained at one or more

levels without clear felling (UK forestry standard,

2011).

The minirhizotron system is designed to slide

down inside a transparent tube in the ground

and to take pictures of roots below-ground.

It allows us to observe root growth over time

and trace single roots in the course of their

development. Within one tube images are taken at ∼ 5 cm intervals every ∼ two weeks.

The acquired images are subsequently

analysed using software which provides us

with information about root length and

diameters of each single image.

Methods

Soil samples will be taken from soil pits but also

from a spatial coring survey across the

selected plots to study and analysed for soil

C, bulk density and nutrients using EU

harmonised soil sampling and analyse

methodology (EU Soil manual, FSCC, 2006).

Sampled will be analysed by Forest Research

Laboratory at Alice Holt.

The purpose of the soil survey is:

• The assessment of basic information on the

chemical soil status and its changes over

time.

• The assessment of soil properties.

• Allow the evaluation of the quality of forest

soils on a European scale.

Globally, the quantity of C stored in the soil is

second only to that in the ocean (38,400 Gt). While the terrestrial biotic C pool is ∼ 560 Gt of

organic C, the soil C pool is more than four

times this figure (Stockmann, et al., 2013).

Soil organic carbon (SOC) is the percentage

measure of C derived from living organisms in

soil. Stability of soil organic matter (SOM) can

be defined in terms of how easily C and

nitrogen in the SOM can be decomposed

(Bajgai, et al., 2013).

Due to the implications in the permanence of

SOC during sequestration there is scientific

interest in fractionation of SOM into different

fractions.

Fine root turnover

http://s0.geograph.org.uk/

http://www.acqu.be//

http://carbon.wr.usgs.gov/

http://www.geert.com/

• http://carbon.wr.usgs.gov/soilclass.html

• http://geert.com/minirhizotron/

• https://mitesisacostarica.wordpress.com/

• http://s0.geograph.org.uk/photos/10/46/104678_dc71b5b5.jpg

ASNW An ancient woodland where the trees and

shrubs are semi-natural, i.e. predominantly

composed of trees and shrubs that are native to

the site and are not obviously planted; features

of ancient woodland often remain (wildlife and

structures of archaeological interest).

https://mitesisacostarica.wordpress.com/

Soil carbon fractionation analysis

References

• Bajgai, Y. et al., 2013. Developments in Fractionation and Measurement of Soil Organic Carbon: A Review. Open Journal of Soil Science, 03(08), pp.356–360. Available at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=41585&#abstract [Accessed May 13, 2016].

• Faget, M. et al., 2010. A minirhizotron imaging system to identify roots expressing the green fluorescent protein. Computers and Electronics in Agriculture, 74(1), pp.163–167. Available at: http://www.sciencedirect.com/science/article/pii/S0168169910001274 [Accessed May 12, 2016].

• FSCC (Forest Soil Co-Ordinating Centre), 2006. Manual IIIa: sampling and analysis of soil. In: ICP Forests, 2006: Manual on Methods and Criteria for Harmonized Sampling, Assessment, Monitoring and Analysis of the Effects of Air Pollution on Forests. UNECE ICP Forests Programme Co-ordinating Centre, Hamburg, 26pp + annexes. http://www.icp-forests.org/Manual.htm.

• Sariyildiz, T., 2015. Effects of tree species and topography on fine and small root decomposition rates of three common tree species (Alnus glutinosa, Picea orientalis and Pinus sylvestris) in Turkey. Forest Ecology and Management, 335, pp.71–86. Available at: http://www.scopus.com/inward/record.url?eid=2-s2.0-84908542692&partnerID=tZOtx3y1 [Accessed

September 10, 2015].

• Sohi, S. et al., 2001. A procedure for isolating soil organic matter fractions suitable for modeling. Soil science society of america journal, 65(4). Available at: http://www.research.ed.ac.uk/portal/en/publications/a-procedure-for-isolating-soil-organic-matter-fractions-suitable-for-modeling(787f7e53-396f-4094-a0cd-b6ff3b2634f5)/export.html [Accessed May 6, 2016].

• Stockmann, U. et al., 2013. The knowns, known unknowns and unknowns of sequestration of soil organic carbon. Agriculture, Ecosystems & Environment, 164, pp.80–99. Available at: http://www.sciencedirect.com/science/article/pii/S0167880912003635 [Accessed December 1, 2015].

• The UK Forestry Standard, 2011, 3rd ed., Edinburgh: Forestry Commission.

Websites:

• Climate Change Act, 2008 - http://www.legislation.gov.uk/ukpga/2008/27/contents

• http://acqu.be/A-LIRE

• http://durhambiodiversity.org.uk/ancient-semi-natural-woodland-including-paws-and-rnwas/

Stockmann, U. et al., 2013