effects of land-use-change scenarios on terrestrial carbon stocks in south korea

13
ORIGINAL PAPER Effects of land-use-change scenarios on terrestrial carbon stocks in South Korea Dong Kun Lee Chan Park Dana Tomlin Received: 1 June 2011 / Revised: 7 October 2013 / Accepted: 23 October 2013 Ó International Consortium of Landscape and Ecological Engineering and Springer Japan 2013 Abstract The amount of carbon stored in soil and vege- tation varies according to land use. Land-use changes (LUCs) affect those carbon stocks. Changes in carbon stocks also affect greenhouse gas emissions. Predicting LUCs is therefore necessary to establish quantitative targets for carbon dioxide (CO 2 ) reduction. This study attempts to model LUCs and the associated changes in carbon stocks for South Korea between 2005 and 2030. It examines four LUC scenarios suggested by the Intergovernmental Panel on Climate Change. Each scenario is assessed in terms of its effect on South Korean carbon stocks. Under all four sce- narios, afforestation leads to carbon sequestration with an average net uptake of 22.4–31.5 MtC. The scenario yielding the highest sequestration rate increase (from 12.4 to 14.1 MtC/year) results in levels of sequestration equal to 8.3 % of South Korea’s 2005 CO 2 emissions. This is equivalent to a value of 304 million dollars in the European Union carbon market. Clear differences among the scenarios tested sug- gest that land use must be regarded as an important factor in any plan for future carbon sequestration. Keywords Biomass Carbon sequestration Climate change Low carbon society (LCS) Soil carbon Introduction Over the past several decades, it has become widely rec- ognized and accepted that the observed increases in the concentration of greenhouse gases (GHGs) have raised global temperatures and altered climate patterns [Inter- governmental Panel on Climate Change (IPCC) 2007]. Between 1989 and 1998, the net removal of carbon from the atmosphere by terrestrial ecosystems has been estimated to have averaged 2.3 GtC/year (IPCC 2000). Throughout the 1990s, however, anthropogenic releases from the carbon pools of terrestrial ecosystems due to land-use changes (LUCs) have been estimated at 1.6 GtC/year (IPCC 2000). The combined result of these natural and anthropogenic processes corresponds to the net removal of carbon from the atmosphere by terrestrial ecosystems (Schlamadinger et al. 2007). Given the significance of emissions/removals and the potential to influence both through policy measures, it will be important to continue to include the Land use, Land- Use Change, and Forestry (LULUCF) guidelines in future international climate-change agreements (Parrotta 2002; Schlamadinger et al. 2007). LUCs not only affect GHG emissions but also carbon stocks associated with soil and vegetation (Feddema et al. 2005; Schulp et al. 2008), as different land uses are associated with different soils and differing amounts of vegetation Electronic supplementary material The online version of this article (doi:10.1007/s11355-013-0235-6) contains supplementary material, which is available to authorized users. D. K. Lee Landscape Architecture, College of Agriculture & Life Science, Seoul National University, San 56-1 Sillim-Dong, Gwanak-Gu, Seoul 151-743, Korea e-mail: [email protected] C. Park (&) Center for Social and Environmental Systems Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Korea e-mail: [email protected] D. Tomlin Landscape Architecture, School of Design, The University of Pennsylvania, 3451 Walnut street, Philadelphia, PA 19104, USA e-mail: [email protected] 123 Landscape Ecol Eng DOI 10.1007/s11355-013-0235-6

Upload: dana

Post on 23-Dec-2016

212 views

Category:

Documents


0 download

TRANSCRIPT

ORIGINAL PAPER

Effects of land-use-change scenarios on terrestrialcarbon stocks in South Korea

Dong Kun Lee • Chan Park • Dana Tomlin

Received: 1 June 2011 / Revised: 7 October 2013 / Accepted: 23 October 2013

� International Consortium of Landscape and Ecological Engineering and Springer Japan 2013

Abstract The amount of carbon stored in soil and vege-

tation varies according to land use. Land-use changes

(LUCs) affect those carbon stocks. Changes in carbon

stocks also affect greenhouse gas emissions. Predicting

LUCs is therefore necessary to establish quantitative targets

for carbon dioxide (CO2) reduction. This study attempts to

model LUCs and the associated changes in carbon stocks

for South Korea between 2005 and 2030. It examines four

LUC scenarios suggested by the Intergovernmental Panel

on Climate Change. Each scenario is assessed in terms of its

effect on South Korean carbon stocks. Under all four sce-

narios, afforestation leads to carbon sequestration with an

average net uptake of 22.4–31.5 MtC. The scenario yielding

the highest sequestration rate increase (from 12.4 to 14.1

MtC/year) results in levels of sequestration equal to 8.3 %

of South Korea’s 2005 CO2 emissions. This is equivalent to

a value of 304 million dollars in the European Union carbon

market. Clear differences among the scenarios tested sug-

gest that land use must be regarded as an important factor in

any plan for future carbon sequestration.

Keywords Biomass � Carbon sequestration �Climate change � Low carbon society (LCS) �Soil carbon

Introduction

Over the past several decades, it has become widely rec-

ognized and accepted that the observed increases in the

concentration of greenhouse gases (GHGs) have raised

global temperatures and altered climate patterns [Inter-

governmental Panel on Climate Change (IPCC) 2007].

Between 1989 and 1998, the net removal of carbon from the

atmosphere by terrestrial ecosystems has been estimated to

have averaged 2.3 GtC/year (IPCC 2000). Throughout the

1990s, however, anthropogenic releases from the carbon

pools of terrestrial ecosystems due to land-use changes

(LUCs) have been estimated at 1.6 GtC/year (IPCC 2000).

The combined result of these natural and anthropogenic

processes corresponds to the net removal of carbon from the

atmosphere by terrestrial ecosystems (Schlamadinger et al.

2007). Given the significance of emissions/removals and

the potential to influence both through policy measures, it

will be important to continue to include the Land use, Land-

Use Change, and Forestry (LULUCF) guidelines in future

international climate-change agreements (Parrotta 2002;

Schlamadinger et al. 2007).

LUCs not only affect GHG emissions but also carbon

stocks associated with soil and vegetation (Feddema et al.

2005; Schulp et al. 2008), as different land uses are associated

with different soils and differing amounts of vegetation

Electronic supplementary material The online version of thisarticle (doi:10.1007/s11355-013-0235-6) contains supplementarymaterial, which is available to authorized users.

D. K. Lee

Landscape Architecture, College of Agriculture & Life Science,

Seoul National University, San 56-1 Sillim-Dong, Gwanak-Gu,

Seoul 151-743, Korea

e-mail: [email protected]

C. Park (&)

Center for Social and Environmental Systems Research,

National Institute for Environmental Studies, 16-2 Onogawa,

Tsukuba, Ibaraki 305-8506, Korea

e-mail: [email protected]

D. Tomlin

Landscape Architecture, School of Design, The University of

Pennsylvania, 3451 Walnut street, Philadelphia, PA 19104, USA

e-mail: [email protected]

123

Landscape Ecol Eng

DOI 10.1007/s11355-013-0235-6

(Jeong et al. 1998; Arrouays et al. 2001; Bellamy et al. 2005;

Schulp et al. 2008). Soil carbon stocks in built-up areas and

croplands are generally lower than those in forestland

(Lamlom and Savidge 2003; Schulp et al. 2008). The con-

version of forestland to other land-use types has been found to

decrease carbon stocks, whereas conversion of other land-use

types to forestland usually leads to increased carbon stocks

[Korea Forest Research Institute (KFRI) 1996; Lettens et al.

2005]. Significantly, forests also store large amounts of car-

bon in vegetation (KFRI 1996; Jeong et al. 1998; Lamlom

and Savidge 2003; Schulp et al. 2008). Among the factors that

will influence future soil carbon stocks, LUCs are expected to

have the largest impact (Smith et al. 2005a).

LUCs occur as the result of complex socioeconomic

activity and physical factors (Verburg et al. 2002; Yim and

Choi 2002; Cho 2008), and future LUC is always uncertain.

To reduce this uncertainty, cellular automata are often used

in spatially explicit experiments that simulate LUC as a

function of user-specified relationships among neighboring

land uses (Verburg et al. 2002). Despite the recent progress

in integrating the biophysical and socioeconomic drivers of

LUC (Verburg et al. 2002; Yim and Choi 2002; Cho 2008),

however, the prediction of future land use remains quite

difficult (Rounsevell et al. 2006). One tool that has proven

helpful in this regard is scenario analysis (Alcamo 2001;

Rounsevell et al. 2006). Recently, a number of studies have

synthetically assessed relationships between LUC and car-

bon-stock change (e.g., Smith et al. 2005b; Zaehle et al.

2007; Schulp et al. 2008). Notwithstanding an increase in

attention to carbon-sink management in climate-change

negotiations and in academic studies, the role of future LUC

in carbon stocks is uncertain in South Korea (Ahn and Han

2004). These uncertainties can be attributed to gaps in our

understanding of both future LUCs and difficulties in

quantifying the response of carbon sequestration to LUCs.

The aim of this study was to model the effects of LUCs on

carbon stocks in South Korea between 2005 and 2030. LUCs

are analyzed using specific LUC scenarios. Carbon-stock

changes are analyzed using a set of high-resolution map.

Methodology

The overall approach to this effort is diagrammed in Fig. 1.

LUC modeling and its scenarios are discussed in more

detail in ‘‘LUC scenarios, LUC modeling’’. The carbon-

stock calculation method is described in ‘‘Calculation of

carbon stock changes’’.

LUC scenarios

Land use has changed significantly throughout South Korea

in recent years, and this trend is likely to continue in the

future. However, it is not easy to predict future LUC, so

several possible scenarios were explored. LUC scenarios

are created based on the four storylines presented in IPCC’s

Special Report on Emission Scenarios. The scenarios are

reviewed by many socioeconomic experts in South Korea.

The four LUC scenarios employed are respectively called

A1, A2, B1, and B2. The A1 and 2 scenarios assume future

oriented more toward economic development than envi-

ronment protection; B1 and 2 scenarios do just the opposite.

In the A and B1 scenarios, international cooperation is

emphasized over regionalism; in the A and B2 scenarios,

the opposite is true. In the A1 scenario, cropland and forest

are the most likely to be urbanized. Regulations protecting

greenbelt areas are lifted to accommodate economic growth

and the expansion of private property, and the control of

cropland development is relaxed due improvements in

agricultural productivity. In the A2 scenario, urbanization

progresses at the same level, but grassland and forest are

more likely to change into cropland because of an increased

need for agricultural products due to a crisis in food secu-

rity. Forest area decreases as it changes into grassland,

urbanization, and cropland, whereas greenbelt and agri-

cultural development regions are kept at present-day levels.

In the B1 scenario, urbanization progresses at a lower level,

and as interest in the natural environment increases, more

cropland and grassland areas are changed into forest as a

result of the Afforestation and Reforestation Clean Devel-

opment Mechanisms (A/R CDM) project that has been

adapted by IPCC to reduce actual carbon dioxide (CO2) in

the atmosphere. As the need to grow bioenergy resources

increases, grassland and forest areas are changed to crop-

land, and developmental controls protecting greenbelt and

cropland areas are kept at present-day levels. In the B2

scenario, as there is little new urbanization, land use

changes into forest occur mainly on marginal cropland

areas, where it is hard to grow agricultural products, and on

grassland areas such as golf courses. Additionally, devel-

opmental controls protecting cropland areas are kept in

place for the reasons of food security (Table 1).

LUC modeling

Land-change modeler (LCM) is used to predict future LUCs.

Land-use transition probabilities have been established by

analyzing correlations between past land usage and sus-

pected driving factors. Legal issues and policies, gross

regional domestic product (GRDP), and scenario-specific

populations were considered as driving factors. Topographic

elevation, slope, distance from roads, and distance from

built-up areas were also used. The multilayer perceptron

(MLP) neural network method is a primary method for

generating land-use transition probabilities. To analyze past

changes in land use, the Korean Ministry of Environment’s

Landscape Ecol Eng

123

Level 1 land-cover maps of 1989 and 1999 were converted

from their original 30 9 30-m resolution to a coarser

100 9 100-m resolution in order to encompass the entire

country, creating files of manageable size. The probabilities

of particular LUC in the future were calculated by applying a

Markov technique. Resulting transition matrixes were then

modified according to the level of urbanization and

economic growth associated with each scenario. The prob-

ability of LUC was also constrained in legislatively protected

conservation areas, such as greenbelts, national parks, the

Demilitarized Zone, the Baekdudaegan, wetlands, conser-

vation forests, waterfronts, agricultural development

regions, forest resource conservation areas, water source

conservation areas, and wild animal and plant protection

Fig. 1 Carbon-stock change calculation

Landscape Ecol Eng

123

areas. These transition rules were ultimately applied to

existing land-use patterns by employing a cellular automaton

technique, which simulates LUC incrementally by repeat-

edly updating discrete locations according to site conditions,

with an immediate vicinity (Yim and Choi 2002; Fang et al.

2005). This method of LUC modeling had demonstrated

good performance in previous regional studies of South

Korea (e.g., Yim and Choi 2002; Lee and Park 2009).

Calculation of carbon-stock changes

To calculate the effects of future LUC on carbon stocks, an

LUC and a carbon-stock calculation method were coupled

(Schulp et al. 2008). Such coupling is difficult due to the

different spatial and temporal resolutions of available LUC

and carbon-stock calculations (Smith et al. 2005a). Most

assessments that address the effect of LUC on carbon stock

strongly simplify the dynamics of LUC (Smith et al. 2005a;

Zaehle et al. 2007; Schulp et al. 2008). Changes in carbon

stock were calculated by considering changes in biomass

associated with LUC and natural growth. Carbon-stock

changes are calculated for each land use or LUC as follows:

Soil stock change ¼ soil carbon stock 2030ð Þ� soil carbon stock 2005ð Þ

Biomass stock change ¼ stem volume incrementation

þ afforestation� deforestation

� decomposition of litter

Changes in carbon stock ¼ soil stock change

þ biomass stock change

Soil carbon stocks start to change to a new equilibrium

after LUC. This is a rapid process that occurs immediately

Table 1 Land-use-change (LUC) scenarios and story lines

LUC

scenarios

Storylines

A1 scenario More cropland and forest is easy to change into urban

use than the other scenarios and are most likely to be

urbanized

Regulations protecting greenbelt areas are lifted to

accommodate economic growth and expansion of

private property

Control of cropland development is relaxed due to

improvements in agricultural productivity

A2 scenario Urbanization progresses at the same level

More grassland and forest are more likely to change

into cropland than other scenarios (food security)

Forest areas decrease as they change into grassland,

urban areas, and cropland

Greenbelt and agricultural development regions are

kept at present level

B1 scenario Urbanization progresses at a lower level

More cropland and grassland areas are changed into

forest (A/R CDM)

Grassland and forest are changed into cropland

(bioenergy)

Developmental controls preserved greenbelts, and

cropland areas are kept at present level

B2 scenario Little new urbanization

Land use changes into forest occur mainly on marginal

cropland areas

Developmental regulations for protecting cropland

areas are kept (food security)

A/R CDM Afforestation and Reforestation Clean Development

Mechanisms

Table 2 Soil carbon stock by land-use type

Forest Paddy

field

Upland

field

Grassland Other

Soil carbon (tC/

ha)

67.9 60.5 45.9 45.9 11.5

Lee et al. (2001)

Table 3 Annual growth rate of stem volume

Coniferous

forest

Deciduous

forest

Mixed

forest

Annual growth rate of stem

volume (m3/ha)

5.68 3.45 4.56

Korea Forest Research Institute (KFRI) (2006)

Fig. 2 Estimation method of total biomass [Korea Forest Research

Institute (KFRI) 2006]

Table 4 Coefficient for carbon-stock calculation by vegetation type

Stem density

(ton/m3)

Biomass

expansion factor

Carbon fraction of

biomass

Coniferous

forest

0.47 1.651 0.5

Deciduous

forest

0.80 1.720 0.5

Mixed forest 0.635 1.685 0.5

Korea Forest Research Institute (KFRI) (2006)

Landscape Ecol Eng

123

after conversion, and it levels off when soil carbon stocks

approach equilibrium (Freibauer et al. 2004; KFRI 2006).

It is expected that equilibrium is reached approximately

20 years after conversion (KFRI 2006). Carbon

accumulation can in fact differ according to the various

characteristics of soils (Lal 2004; Smith et al. 2008). The

change in soil carbon stock as a consequence of land-use

conversion depends on the differential sizes of the soil C

pool between land-use types at equilibrium (Zaehle et al.

2007). To estimate carbon accumulation in soil, the

methods of Lee et al. (2001) were used with five types of

land use: forest, paddy field, upland field, grassland, and

others (Table 2). Land-cover maps were converted into five

land-use categories: soil under forest area, 67.9 tC/ha;

paddy field, 60.5 tC/ha\; upland field, 45.9 tC/ha; grassland,

45.9 tC/ha; and other areas, 11.5 tC/ha (Lee et al. 2001).

All soil carbon-stock changes consider the upper 30 cm of

the soil (Lee et al. 2001; Schulp et al. 2008).

Carbon accumulation in vegetation was calculated by

considering stem-volume incrementation, afforestation,

deforestation, and decomposition of litter between 2005

and 2030. Stem-volume incrementation is considered in

Fig. 3 Land-use change

Fig. 4 Result of land-use change in A1 scenario (see text for definition)

Landscape Ecol Eng

123

areas designated as forest-land-remaining-forest-land,

afforestation, and deforestation areas. Tree growth acts as a

carbon sink in forest-land-remaining-forest-land and

afforestation areas, but it acts as a carbon source in

deforestation areas. For forest-land-remaining-forest-land

areas, we calculated stem-volume incrementation from

Fig. 5 Result of land-use change in A2 scenario (see text for definition)

Fig. 6 Result of land-use change in B1 scenario (see text for definition)

Landscape Ecol Eng

123

2005 to 2030. Stem-volume increase is shown in Table 3.

We also assumed a constant annual rate of LUC in order to

calculate carbon emissions caused by LUCs. Afforestation

and deforestation exhibit only half as much stem-volume

incrementation. Carbon budgets were calculated using the

total biomass and a carbon fraction of biomass. Total

biomass is the sum of stem, branch, and root biomass. To

calculate branch and root biomass, biomass expansion

factor measured by KFRI was used (Fig. 2; Table 4).

Stem-volume incrementation was applied to the annual

growth rate in stem volume for vegetation types suggested

by the KFRI. The coefficient of carbon-stock calculations

by vegetation type reflected the value suggested by KFRI

(Table 4). We assumed that land converted to forest area

will be an afforestation field covered by coniferous trees

averaging 15 years old. For forest converted to other land

uses, we assumed that vegetation was all deforested and

60 % of living biomass, such as litter and roots, would

decay (KFRI 2006). The drop caused by exploiting forests

was calculated considering total biomass, including growth

until forests and existing biomass were exploited. The

volume of the accumulation of standing trees in existing

forests was calculated by using inventory data from the

South Korea Forest Service, reflecting the accumulation

density for each region. The IPCC (1996) guidelines for

LULUCF were used as the basic method for calculating the

volume of carbon accumulation. Accumulated carbon stock

is described in tons of carbon units.

Results

LUC results

Four scenarios are generated with different land-use

options regarding the demands and present land-use pattern

prevailing in the country. Results of the LUC model are

presented in Fig. 3. Note here that all scenarios result in the

reduction of cropland, whereas forest area increase in every

scenario except for A1. The scenarios also differ in their

spatial patterns of LUC, particularly the conversion of

forest and cropland to other land-use types. Concrete

results for LUCs in each scenario are as follows (Figs. 3, 4,

5, 6, 7, Appendix 2):

In the A1 scenario, urbanization occurred rapidly. Built-

up areas ultimately encompass 7,264 km2 (Fig. 3, left), or

110 % more area than in 1999 (Fig. 3, right). By contrast,

the areas of cropland and forest are reduced, with the area

of forest decreased by 2.2 %. Urbanization primarily

occurs on flat lowlands, occasionally replacing agriculture.

Land around Seoul and other major metropolitan areas is

especially susceptible to urbanization (Fig. 4). In the A2

scenario, urbanization encompasses 41.8 % less area than

in the A1 scenario (Fig. 3, right), due largely to the con-

tainment of byways of greenbelts. In this scenario, devel-

opment tends to occur in the suburbs of Daejeon, Daegu,

and Busan rather than Seoul, reflecting GRDP growth

(Fig. 5). In the B1 scenario, urbanization increases by

Fig. 7 Result of land-use change in B2 scenario (see text for definition)

Landscape Ecol Eng

123

49.0 % of the A2 scenario in 2030. With the changeover of

croplands and grasslands into forests, the forest area

increases 3.85 % more than in 1999, and the decrease in

cropland of 5.2 % is lower than that in the A1 scenario of

8.6 % (Fig. 3, right). Fewer cropland areas near Seoul are

urbanized than in other scenarios, and urbanization focuses

on major cities throughout the country. Cropland increases

in the northeastern (Gangwon Province) and south-

western (Jeonnam Province) parts of South Korea, where

population levels drop sharply. Wetland areas also

increase. LUC also tends to occur within the city more

often than in suburbs (Fig. 6). In the B2 scenario, the

amount of urbanized, cropland, and other land-use areas

decreases. Forest areas, however, increase by 4.6 % com-

pared with 1999. Cropland decreases by 0.2 %, whereas

other areas decrease by 30.7 % and grassland by 56.7 %

compared with 1999 (Fig. 3, right). Urbanization occurs in

rural areas more frequently (Fig. 7).

Table 5 Accumulated carbon stock in living biomass in forest-land-

remaining-forest-land areas (2006–2030)

Coniferous

forest

Deciduous

forest

Mixed

forest

Total

A1

Area (1,000 ha) 2,527 1,618 1,553 5,700

Stem-volume

increment

(1,000 m3)

358,973 139,608 177,121 675,702

Accumulated

carbon stock

(MtC)

139.2 96.1 94.9 330.2

A2

Area (1,000 ha) 2,563 1,629 1,572 5,764

Stem-volume

increment

(1,000 m3)

363,901 140,556 179,278 683,735

Accumulated

carbon stock

(MtC)

141.2 96.7 96.1 334.0

B1

Area (1,000 ha) 2,543 1,629 1,561 5,734

Stem-volume

increment

(1,000 m3)

361,240 140,531 177,945 679,716

Accumulated

carbon stock

(MtC)

140.1 96.7 95.4 332.2

B2

Area (1,000 ha) 2,592 1,639 1,586 5,818

Stem-volume

increment

(1,000 m3)

368,139 141,352 180,859 690,350

Accumulated

carbon stock

(MtC)

142.8 97.2 96.9 337.0

Table 6 Accumulated carbon stock in living biomass in land con-

verted to forest land (2006–2030)

A1

(MtC)

B1

(MtC)

B1

(MtC)

B2

(MtC)

Accumulated carbon stock 22.4 28.8 32.5 31.5

Table 7 Accumulated decrease in carbon stocks in living biomass

due to deforestation (2006–2030)

Coniferous

forest

Deciduous

forest

Mixed

forest

Total

A1

Deforestation area

(1,000 ha)

303 82 129 514

Stem-volume

increment

(1,000 m3)

21,537 3,550 7,367 32,454

Accumulated stem

volume

(1,000 m3)

44,750 10,154 19,137 74,041

Decrease in carbon

stock (MtC)

17.3 6.9 10.2 34.6

A2

Deforestation area

(1,000 ha)

268 71 110 449

Stem-volume

increment

(1,000 m3)

19,073 3,076 6,288 28,437

Accumulated stem

volume

(1,000 m3)

39,630 8,798 16,335 64,763

Decrease in carbon

stock (MtC)

15.3 6.0 8.7 30.2

B1

Deforestation area

(1,000 ha)

287 72 122 481

Stem-volume

increment

(1,000 m3)

20,404 3,088 6,955 30,447

Accumulated stem

volume

(1,000 m3)

42,395 8,833 18,067 69,295

Decrease in carbon

stock (MtC)

16.5 6.1 9.7 32.2

B2

Deforestation area

(1,000 ha)

239 62 97 398

Stem-volume

increment

(1,000 m3)

16,955 2,678 5,498 25,131

Accumulated stem

volume

(1,000 m3)

35,228 7,660 14,282 57,170

Decrease in carbon

stock (MtC)

13.8 5.3 7.7 26.6

Landscape Ecol Eng

123

Future carbon-stock change

Predicted increases in biomass and carbon accumulation by

tree growth in forests are shown in Table 5. In all LUC

scenarios, coniferous forests accumulate a large amount of

carbon as a result of both tree growth and geographic

expansion. Deciduous forests are more effective in reducing

carbon; 337.0 MtC is predicted to accumulate in forest-land-

remaining-forest-land areas from 2005 to 2030 for the B2

scenario. The amount of accumulated carbon stocks by

afforestation over 25 years could be calculated as shown in

Table 6. Carbon stock by afforestation is largest in the B1

scenario due to land conversion. Carbon emissions resulting

from commercial cutting are greatest in A1. Coniferous

forest generally showed more carbon emission in total by

LUCs (Table 7). Scenario A1 showed the highest CO2

source in living biomass, i.e., branches and roots (Table 8).

Soil carbon reduction was the highest in scenario B2 and

lowest in scenario A1. Carbon uptake in soil is shown in

Table 9.

There were significant differences in carbon sequestra-

tion among the four scenarios. The dynamics of net carbon

uptake by forests follow carbon uptake through biomass

growth, and differences among scenarios were mainly the

Table 8 Accumulated decrease in branch and root carbon stocks

(2006–2030)

From To A1

(MtC)

A2

(MtC)

B1

(MtC)

B2

(MtC)

Coniferous

forest

Cropland 1.75 1.54 1.98 1.79

Grassland 0.90 0.81 0.32 0.47

Others 0.85 0.75 0.97 0.36

Deciduous

forest

Cropland 0.90 0.77 0.89 0.92

Grassland 0.56 0.53 0.20 0.33

Others 0.47 0.37 0.61 0.19

Mixed forest Cropland 1.03 0.88 1.22 1.05

Grassland 0.61 0.56 0.23 0.34

Others 0.58 0.45 0.64 0.22

Total 7.68 6.69 7.09 5.67

Table 9 Net change in soil

carbon stocks between 2005 and

2030

a soil carbon stock in 2005b soil carbon stock in 2030

Land Use Area (2005)

(1,000 ha)

Area (2030)

(1,000 ha)

Carbon stock

(2005)a (MtC)

Carbon stock

(2030)b (MtC)

Net change

(2030-2005)b-a (MtC)

A1 scenario

Paddy field 1,452 1,127 87.86 68.19 -19.67

Upland field 1,108 860 50.85 39.46 -11.39

Forest 6,215 6,517 422.01 442.48 20.47

Grassland 187 405 8.58 18.61 10.03

Others 1,062 1,115 12.21 12.82 0.61

Total 581.52 581.57 0.05

A2 scenario

Paddy field 1,452 1,127 87.86 68.19 -19.67

Upland field 1,108 860 50.85 39.46 -11.39

Forest 6,215 6,810 422.01 462.38 40.37

Grassland 187 292 8.58 13.39 4.81

Others 1,062 936 12.20 10.75 -1.45

Total 581.52 594.19 12.67

B1 senario

Paddy field 1,452 1,167 87.86 70.60 -17.25

Upland field 1,108 890 50.85 40.86 -9.98

Forest 6,215 6,916 422.01 469.57 47.55

Grassland 187 207 8.58 9.50 0.91

Others 1,062 844 12.21 9.70 -2.50

Total 581.53 600.25 18.72

B2 scenario

Paddy field 1,452 1,231 87.86 74.48 -13.38

Upland field 1,108 939 50.85 43.11 -7.74

Forest 6,215 6,962 422.01 472.71 50.70

Grassland 187 188 8.58 8.63 0.05

Others 1,062 704 12.20 8.09 -4.11

Total 581.52 607.03 25.51

Landscape Ecol Eng

123

result of the different amounts of biomass growth

(Table 10). In all scenarios, the amount of carbon increased

over that period; 11.6–42.2 MtC of carbon accumulation

will be reduced due to LUC.

In this study, results of carbon-stock change were

strongly influenced by the conversion rate of abandoned

agricultural areas to forest. This indicates that land-use

policy has the potential to exert a significant influence on

terrestrial carbon.

Discussion

Simulated present-day carbon stocks in soil and vegeta-

tion, as well as their temporal changes, are in reasonable

agreement with independent estimates based on the

extrapolation of soil surveys, forest inventories, and

modeling efforts (Zaehle et al. 2007). Terrestrial carbon

stock around the world sink 373 GtC in vegetation and

1,086 GtC in soil (Lal 2004). Forest ecosystems covering

about 4.1 billion hectares globally are a major reserve of

terrestrial carbon stock (Smith et al. 2008). Several studies

have estimated the carbon sequestration potential in Eur-

ope and other countries for various LUC scenarios. Smith

et al. (2005a, b) estimate future soil carbon changes of

pasture, cropland, and forest using LUC scenarios of

Rounsevell et al. (2005). For agricultural land, effects of

changes in climate and technology are assessed, whereas

for forest, the effect of changes in climate and litter input

are assessed. Zaehle et al. (2007) assess European terres-

trial carbon-stock change that results in changes in cli-

mate, net primary production (NPP), technology, and land

management. Schulp et al. (2008) assess only effect of

LUC on vegetation and soil carbon stock using Rounsevell

et al.’s (2005) LUC scenarios. Tavoni et al. (2007)

examine the role forestry may play in the context of

atmospheric CO2 stabilization in Organisation for Eco-

nomic Co-operation and Development (OECD) and non-

OECD countries.

Results of different studies on future carbon sequestra-

tion and LUC are hard to compare. Studies on the effect of

future LUC on carbon sequestration are different in

approach, time span, resolution, estimates of terrestrial

carbon balance, and scenario elaboration. A net sink of

12.4–14.1 MtC years-1 was found for South Korea

between 2005 and 2030 (Table 10). This sink is less than

that of 25.5–31.3 MtC years-1 assessed in the European

Union (EU) of 12 member states (EU12), and of 16.3–83.9

MtC years-1 in the EU of 15 member states (EU15)

(Table 11). Several factors can account for potential dif-

ferences in carbon sequestration. On average, European

forests annually sequester 1.24 tC ha-1 from the atmo-

sphere (Janssens et al. 2005). On the other hand, South

Korean forests annually sequester 2.32 tC ha-1 (KFRI

2006). Obviously, countries with high forest cover tend to

have a higher forest carbon sink per unit of total land area

than countries with low forest cover (Janssens et al. 2005).

The mean biomass density method used in this study is

widely used to estimate regional-, national-, and global-

scale forest biomass (Guo et al. 2010). Linear growth curve

is used for tree growth by vegetation type. In reality, this

could lead to underestimating young and overestimating

old forests (Fang et al. 2005). Nevertheless, some studies

found no significant difference in relationships across for-

est age classes for mixed forest types (Guo et al. 2010).

European studies [e.g., Smith et al. (2005a, b); Zaehle et al.

2007; Schulp et al. 2008] assumed that carbon losses are

estimated by multiplying carbon stocks with specific

Table 10 Accumulated carbon-stock change in the four scenarios (2006–2030)

A1 2030 (MtC) A2 2030 (MtC) B1 2030 (MtC) B2 2030 (MtC)

Vegetation Stem-volume increment 330.3 334.0 332.2 337.0

Afforestation � 22.4 28.7 32.2 26.5

Deforestation ` -34.6 -30.1 -32.5 -31.5

Litter ´ -7.6 -6.6 -7.1 -5.6

Soil Soil carbon stock ˆ 0.05 12.6 18.7 25.5

Direct carbon loss due to LUC (` ? ´ ?ˆ ) -42.2 -24.2 -20.9 -11.6

Net change of carbon stock due to LUC (� ? ` ? ´ ?ˆ ) -19.8 4.5 11.3 14.9

Total accumulated carbon stock 310.4 338.5 343.5 351.9

Average annual increment in carbon stock 12.4 13.5 13.7 14.1

Table 11 Carbon sequestration between 2005 and 2030 (MtC

years-1) in the four scenarios (recalculated from Zaehle et al. 2007;

Schulp et al. 2008)

Scenario A1 A2 B1 B2

Schulp et al. (2008) (EU15) 79.1 61.7 83.9 80.3

Schulp et al. (2008) (EU12) 25.5 28.8 27.6 31.3

Zaehle et al. (2007) (EU15) 34.6 37.1 21.2 16.3

This study (South Korea) 12.4 13.5 13.7 14.1

Landscape Ecol Eng

123

decomposition rates. Carbon emissions from croplands

are demonstrated to depend on the soil carbon content

(Bellamy et al. 2005).

KFRI (2006) reports that South Korean forest uptake

was 9.1 MtC in 2001. Considering afforestation and refor-

estation, the differences in carbon sequestration between

2001 and 2030 is reliable. Tavoni et al. (2007) estimate 25

MtC years-1 of carbon sequester in South Korea, South

Africa, and Australia. Compared with this research, results

are considerably unreliable. However, differences are in

basic assumptions. Tavoni et al. (2007) consider managed

forest and afforestation result from LUC.

When comparing our study presented here with the 2001

IPCC report, which presents carbon emission changes by

LUC until 2030, the emission pattern for each scenario is

similar. According to the IPCC report, for the A1 scenario,

carbon emission will steadily increase until 2020 and in

2030 will be absorbed by LUCs. Carbon will also be

continuously absorbed in the B1 and B2 scenarios (IPCC

2001). According to results of our study, 19.8 MtC will be

passed in scenario A1 in 2030. In the A2, B1, and B2

scenarios, carbon accumulation will increase by 4.6–14.9

MtC. The characteristics shown in the IPCC report are

similar to the characteristics of this study (Fig. 8).

Several studies in the forestry literature have estimated

the sequestration potential for various given carbon prices,

and most seem to agree that forestry can provide a sig-

nificant share of abatement. As an example, it is worth

remembering that tropical deforestation is a major source

of GHG emissions, accounting for as much as 25 % of

global anthropogenic GHG emissions (Houghton et al.

1999). In our A1 scenario, South Korea will lose 19 million

dollars annually due to direct effects of LUCs but will gain

14 million dollars annually in scenario B2. The maximum

difference in athe value of carbon reduction in the four

scenarios is 33 million dollars/years in the EU carbon

market (Table 12). Taking into account social and eco-

nomic constraints, however, a smaller amount of carbon

sequestration will more likely occur.

Conclusion

In this study, naturally absorbed carbon accumulation

resulting from LUC is analyzed in order to set reduction

goals and devise a strategy for building a low-carbon

society in South Korea. This is one of the first assessments

of carbon-stock changes that fully accounts for the

dynamics of LUC in South Korea. Based on LUC projec-

tions, we anticipate carbon reduction levels of between

12.5 MtC and 14.1 MtC each year in soil and vegetation. In

fact, the A1 scenario predicts a reduction of 19.8 MtC

annually over 25 years. In the B2 scenario, an annual

reduction of 14.9 MtC is predicted. The B1 scenario seems

to be most in line with a future low-carbon society (LCS),

as it has the highest carbon reduction effect. The B1

Fig. 8 Global carbon dioxide

(CO2) emissions due to land-use

change (Intergovernmental

Panel on Climate Change 2001)

Table 12 Effect of land-use change (LUC) on carbon stock and

economic value

A1

(millions

of dollars/

year)

A2

(millions

of dollars/

year)

B1

(millions

of dollars/

year)

B2

(millions

of dollars/

year)

Direct effect of

LUC

-19 4 11 14

Net change of

carbon stock

due to LUC

269 289 291 304

Landscape Ecol Eng

123

scenario, which reduces areas of development, uses bio-

mass energy sources from agriculture and allows for the

use of solar, wind, and geothermal energy, which is

appropriate when compared with the A1 scenario repre-

senting socioeconomic development in the past. When it

comes to land-use policy, it is necessary to break out of

existing paradigms. Policy should be shifted from the

expansion of urban areas for stimulating economic growth

to the increase of available land through renewal of exist-

ing urban areas and increasing the efficient use of space.

This study demonstrates the importance of LUC as a major

factor affecting both carbon sources and sinks. The high

release of carbon associated with old-growth deforestation

and the potential for carbon sequestration associated with

cropland abandonment stress the importance of carefully

assessing future LUC.

Acknowledgments This research was supported by a grant (07High

Tech A01) from High tech Urban Development Program funded by

Ministry of Land, Transportation and Maritime Affairs of Korean

government.

References

Ahn S, Han K (2004) Feasibility Study for Estimating the Cost of

Carbon Sink in Korea. Environment Institute, Korea

Alcamo J (2001) Scenarios as tools for international environmental

assessments. Environmental Issue Report No. 24, European

Environmental Agency, Copenhagen

Arrouays D, Deslais W, Badeau V (2001) The carbon content of

topsoil and its geographical distribution in France. Soil Use

Manag 17:7–13

Bellamy PH, Loveland PJ, Bradley RI, Lark RM, Kirk GJD (2005)

Carbon losses from all soils across England and Wales

1978–003. Nature 437:245–248

Cho D (2008) Cellular automata based urban landuse change

modeling considering development density. J Korean Geogr

Soc 41(3):117–133

Fang S, Gertner GG, Sun Z, Anderson AA (2005) The impact of

interactions in spatial simulation of the dynamics of Urban

Sprawl. Landscape Urban Plan 73(4):294–306

Feddema JJ, Oleson KW, Bonan GB, Mearns LO, Buja LE, Meehl GA,

Washington WM (2005) The importance of land-cover change in

simulating future climates. Science 310(5754):1674–1678

Freibauer A, Rounsevell MDA, Smith P, Verhagen J (2004) Carbon

sequestration in the agricultural soils of Europe. Geoderma

122:1–23

Guo Z, Fang F, Pan Y, Birdsey R (2010) Inventory-based estimates of

forest biomass carbon stocks in China: a comparison of three

methods. For Ecol Manage 259(7):1225–1231

Houghton RA, Hackler JL, Lawrence KT (1999) The U.S. carbon

budget: Contributions from land-use change. Science 285(5427):

574–578

Intergovernmental Panel on Climate Change (1996) Revised IPCC

Guideline for National Greenhouse Gas Inventories

Intergovernmental Panel on Climate Change (2000) Land use, land-

use change and forestry, a special report of the IPCC. Cambridge

University Press

Intergovernmental Panel on Climate Change (2001) IPCC Special

Report on Emissions Scenarios, GRID-Arendal website

Intergovernmental Panel on Climate Change (2007) IPCC Fourth

Assessment Report: Climate Change

Janssens IA, Freibauer A, Schlamadinger B, Ceulemans R, Ciais P,

Dolman AJ, Heiman M, Nabuurs GJ, Smith P, Valentini R,

Schulze ED (2005) The Carbon Budget of Terrestrial Ecosys-

tems at Country Scale—a European Case Study. Biogeosciences

2:15–26

Jeong J, Kim C, Lee W (1998) Soil organic carbon content in forest

soils of Korea. J Forest Sci (in Korean) 57:178–183

Korea Forest Research Institute (1996) Korean people and Carbon

dioxide, 126

Korea Forest Research Institute (2006) Development of GHGs

Emission Inventory System for climate change convention

Lal R (2004) Soil Carbon Sequestration impacts on global climate

change and food security. Science 304:1623–1627

Lamlom SH, Savidge RA (2003) A reassessment of carbon content in

wood: variation within and between 41 North American species.

Biomass Bioenergy 25(4):381–388

Lee D, Park C (2009) The Analysis of Potential Reduction of CO2

Emission in Soil and Vegetation. J Korean Soc Environ Restor

Technol 12(2):95–105

Lee K, Son Y, Kim Y (2001) Greenhouse gas inventory in land-use

change and forestry in Korea. J Forest Energy 20(1):53–61

Lettens S, Jv Orshoven, Bv Wesemael, Muys B, Perrin D (2005) Soil

organic carbon changes in landscape units of Belgium between

1960 and 2000 with reference to 1990. Glob Change Biol

11:2128–2140

Parrotta JA (2002) Restoration and management of degraded tropical

forest landscapes. In: Ambasht RS, Ambasht NK (eds) Modern

trends in applied terrestrial ecology. Kluwer Academic/Plenum

Press, New York, pp 135–148

Rounsevell MDA, Ewert F, Reginster I, Leemans R, Carter TR (2005)

Future scenarios of European agricultural land use. II. Proj

Changes Cropland Grassland Agriculture Ecosystem Environ

107(12):117–135

Rounsevell MDA, Reginster I, Araujo MB, Carter TR, Dendoncker N,

Ewert F, House JI, Kankaanpaa S, Leemans R, Metzger MJ,

Schmit C, Smith P, Tuck GA (2006) Coherent set of future land

use change scenarios for Europe. Agriculture Ecosystem Environ

114(1):57–68

Schlamadinger B, Bird N, Johns T, Brown S, Canadell J, Ciccarese L,

Dutschke M, Fiedler J, Fischlin A, Fearnside P, Forner C,

Freibauer A, Frumhoff P, Hoehne N, Kirschbaum MUF, Labat A,

Marland Michaelowa A, Montanarella L, Moutinho P, Murdiyarso

D, Pena N, Pingoud K, Rakonczay Z, Rametsteiner E, Rock J, Sanz

MJ, Schneider UA, Shvidenko A, Skutsch M, Smith P, Somogyi Z,

Trines E, Ward M, Yamagata Y (2007) A synopsis of land use,

land-use change and forestry (LULUCF) under the Kyoto protocol

and marrakech accords. Environ Sci Policy 10(4):271–282

Schulp CJE, Nabuurs GJ, Verburg PH (2008) Future carbon

sequestration in Europe: effects of land use change. Agric

Ecosyst Environ 127(3–4):251–264

Smith JU, Smith P, Wattenbach M, Zaehle S, Hiederer R, Jones RJA,

Montanarella L, Rounsevell MDA, Reginster I, Ewert F (2005a)

Projected changes in mineral soil carbon of European croplands

and grasslands, 1990–2080. Glob Change Biol 11(12):2141–2152

Smith P, Smith JU, Wattenbach M, Meyer J, Lindner M, Zaehle S,

Hiederer R, Jones RJA, Montanarella L, Rounsevell MDA,

Reginster I, Kankaanpaa S (2005b) Projected changes in mineral

soil carbon of European forests, 1990–2100. Can J Soil Sci

86:159–169

Smith P, Fang C, Dawson JJC, Moncrieff JB (2008) Impact of global

warming on soil organic carbon. Adv Agron 97:1–43

Landscape Ecol Eng

123

Tavoni M, Sohngen B, Bosetti V (2007) Forestry and the carbon market

response to stabilize climate. Energy Policy 35:5346–5353

United Nations Framework Convention on Climate Change (2003)

Land use, Land-use change and forestry: definitions and

modalities for including afforestation and reforestation activities

under Article 12 of the Kyoto Protocol. Submissions from

Parties, FCCC/SBSTA/2003/MISC, Bonn

Verburg PH, Soepboer W, Veldkamp A, Limpiada R, Espaldon V,

Mastura SSA (2002) The spatial dynamics of regional land use:

the CLUE-S model. Environ Manage 30(3):391–405

Yim C, Choi D (2002) Predicting micro land use dynamics. A cellular

automata modelling Approach, Journal of the Korean planners

association 37(4):229–239

Zaehle S, Bondeau A, Carter T, Cramer W, Erhard M, Prentice I,

Reginster I, Rounsevell M, Sitch S, Smith B, Smith P, Sykes M

(2007) Projected changes in terrestrial carbon storage in Europe

under climate and land-use change, 1990–2100. Ecosystems

10(3):380–401

Landscape Ecol Eng

123