A broad leaf species alters and evenly distributes soil organic carbon chemical composition in a Pinus masso11ia11a planted forest in southern China Hui Wang

A broad leaf species alters and evenly distributes soil organic carbon chemical composition in a Pinus masso11ia11a planted forest in

southern China

Hui Wang1_{, Shirong Li11}1_{, Jingxin Wan,}i_{, Zuomin Shi}1_{. Daoxiong Cai', Lihua Lu'. Angang Ming'}

1_{!ns1iw1e o/Fon!st Ecolog;; Em·irou111c111 a11d Protection. C'hi11ese Academy of Fores11y, Beijing, China; 'Dil'isio11 of Forest1y and Natural Resources, West} Vi1ginia Universi(J, Mo1gantoll'11. USA; 'Experimental Center of Tropical Foresll): Chinese Academy of Forestry Pingxiang. China (wangl111i@caf.ac.c11: liusr@caj.'ac.cn: jxll'ang@lVvu.edu: shi:111@cof.'ac.cn: rl:xcdx@!26.co111; kjc8526 / 36@l 63.com: 111i11gangangO / I !@I63.com}

There are potential effects of planted forest type conversions from conifer to broad leaf or mixed-species on the soil organic carbon (SOC) chemical composition, and the evenness of its distribution remains uncertain. An afforestation experiment with diff_{erent tree species (Pinus massoniana, Erythrophleum fordii, and} mixed P 111assoniana and E. fordii) was conducted in a clear-cutting site of P 111asso11iana pln111ed forests in a subtropical region. Topsoil organic C quality and microbial diversity were assessed a tier eight years of afforestation. The proportions of alkyl C and carbonyl C in SOC, as well as alkyl C/0-alkyl C ratios and the evenness of the SOC chemical composition distributions were higher in monospecitic £. fordii and mixed-species planted forests than the monospecific P massoniana planted forest. The positive relationship of SOC chemical composition distribution with litter as well as fine root C quality was observed. Microbial biomass C was positively correlated with the labile SOC. Fine root C had a closer correlation with the chemical composition of SOC than litter. The present results are not consistent with our previous findings in a 25-year afforestation site, in which soil microbial community composition rather than litter quality was linked with SOC chemical composition, suggesting plant C chemical composition would better predict belowground C sequestration functioning in the earlv afforestntion system. These results highlight that mixing native N fixing broadleaf species into conifer forests probably enhance the SOC chemical stability and resistance to climate change by increasing the recalcitrant C components and the evenness of SOC distribution.

Allometric models to estimate biomass aboveground in forest recovery areas

Anani J.fori/ha Zanini1_{, Raftrella Mayri11ck'. Bm11a Santos Lopes'. Si111011e Aparecida Vieim}3_{, Ricardo Ribeiro Rodrigues}1

1_{Esco!a Superior de Agricu!t11ra Lui: de Queiro:, Universidade de Siio Paulo, !'iracicaha, Bra:il; 'University of Saskatchewan, Saskatvvn, Canada;} 'Universidade Esrad11al de Ca111pi11as. Campi11as, Bra:il (anani:a11i11i@ho1111ail.co111: rafamk@ho1111ail.com: bmna.santos.!opes@usp.br: sal'ieira08@gmail. co111: rrresalq@usp.b1)

Quantify carbon stock on forest restaurntion areas is a global interest, since this area provide the important environmental service of mitigating climate change. It is crucial have more studies on allornetry to help on predicting biomass and carbon stocking for those areas. Thus, the objective of this study was to quantify forest biomass and carbon content to a 5-year-old region under restoration process, so models could be fitted to the area and also used to similar sites. Three sites nearby ltu city. SP, Brazil, were studied,

5

years after the restoration process was implemented. In each site, three 900 m'-plots were installed, and a forest inventory was done, measuring tree height and circumference at breast height. Sub-plots (25 m') were randomly selected in each 900 m'-plots and all trees inside it were cut and had its volume measured. stratified into foliage, roots and stern pools. Carbon content was detennined on the Isotopic Ecology Laboratory for each species and pool. This data was used to fit models 10 estimate biomass. The best model was selected using the adjusted coefficient of deiermination (R'), residual charts and Akaike's information criterion (AIC). Mean biomass for the area was 20.19±0.146 Mg ha-•, mean Carbon stock was 9.73 Mg C ha-•, and average carbon content was 45.31%.

N

₂

fixing trees (Acacia 111a11giu111) introduce in eucalypt plantations modify rapidly the pools of organic P and low-molecular-weight

organic acids (Li\lWOAs) in tropical soils contrasted for their C/P stoichiometry

Kilfima l-Vair/Jaisong1_·2_{, Agnes Robin'·'. Lvnis Marescha/3, Jean-Pierre Bouillet;. Jea11-Pa11/ Lac/au', Jose Leonardo de Moraes Gom;alves', .\.!a11011} Villeneuve', Philippe Delepone'. Claude Plassarc/1

1 _{!NRA/ Ui'v/R Eco&Sols, Monlpellier, France; : Depanment of Microbiology, Faculty oj'Sciencc Silpakorn Unirersity-Sanam Chandra Palace Campus,} Nakhon Parlrom, Thaila11d; 'CJ RAD, UMR Eco&Sols, Montpel/ie1: Fi·cmce: 'Esco/a Superior de Agricultura Lui: de Q11eiro:, Universidade de Soo Paulo. Piracicaba. Brasil; 5/RD. UMR Eco&Sols, Montpellie1; France (killi111a22l./@g111ail.co111; agnes.robin@cimdfi': lo11is.111areschal@cirad.fr;jean-pierre. bo11i/lct@cirad.fr: /ac!a11@ciradji-; jlmgo11ca@11sp.hr; 111a11on. vi/lenel(ve@irdji-; philippe.delcporte@cirad.fi·; p/assard@s11pagro.inraji-}

In this study. soil organic P (Po) and low-molecular-weight organic acids (LMWOAs) were quantified under different land uses in order to investigate lhe effect ofN, fixing tree introduciion on phosphorus cycle. Soils were collected from plantations of pure acacia (Ac). pure eucalyptus tEuc) or both species (50/50) and original savannahs (S) that were located in Brazil (low P, high and high C soil) and in Congo (high P. low N and lo\\· C soil). Po and LMWOAs were identified in sodium hydroxide soil extracts with ion chromatography (IC). Phosphate monoesters as AMP and glucose-6-phosphate (G6P) were the main Po forms in both sites. Phytate, ATP and J'ructose-bisphosphate (FrucbisPJ were also present as well as the mineral form of pvropl1osphate (PrP). Malate, oxalate and malonate were the major components of UvIWOA fraction in the two soils. Citrate was also present at low concentrations. lnterresingly, phytate concentrations were always decreased under acacia plantations. This could result from a better mineralisation or lower inputs into these soils. In mixed stands, the effect of acacia introduction on Po and LMWOAs composition is more pronounced in high P than in low P soil, due to a much better N, fixa1ion. Our results highlighi that 1he introduction of a legume tree is able to strongly modify the composition of Po and LMWOAs in soil even after a nrst short-time rotation. especially when the rate of N, fixation is high.

Microbial enzymatic activities and community-level physiological profiles (CLPP) in subsoil layers arc altered by harvest residue

management practices in a tropical

£11ca�1'pl11s gra111fis plantation

Fran1·ois Maillard1_{, Valentin Leduc}1_{, Cyrille Ba,N, Jose Leonardo de ;\./oraes Gonralves', Femando Dini Andreote}1_{, Lauren/ Saint-Andre}3_, Jean-Paul Lac/aJ(1_{, .Hare Buee}1_{. Agnes Robin''}

'(,'niversitci de Lorraine. /SRA. /AM. 1\'anc,·. France: 'Esco/a Superior de .·lgric11/J11ra Lui: de Q11eiro:, Umrersidade de Sc)o Paulo. Piracicaba, Brasil: -'J.VRA UR 1138 Biogeochimie des Ecosystemes Foresriers .. Yancy Fmnce; 'CIRAD, UMR Eco&Sols .. \Iontpellie1: France ((rancois.maillard@iflmjr; 1·afenti11/cd11c@ho1111ail.fr: C)'l'ille.bach@i11ra.fr_{:jl111gonca@11sp.br;fda11dreu@g111aif.co111: !aure111.sai11t-a11dre@inra.fr: laclmr@ciradji-: 111arc.b11ee@i11ra.} fr: 11gnes.robi11@c·irar/.ji)

Harvest residue management is a kev issue for the sustainability of Eucalyptus plantations established on poor soils. Soil microbial communities contribute to soil fertility by the decomposi1ion of the organic matter (OM), but little is known about the effect of whole-tree harvesting (WTH) in comparison to stem onlv harvesting (SOHJ on soil microbial functional diversity _{in Eucalyptus plantations. We studied the ef}f_{ects of harve�t residue management (branches. leaves.}

bark) of Eucalvptus gmndis trees on s,iil enzymaiic activities and communily-level physiological profiles in a Brazilian plantation. We measured soil microbial

Pesq.f/01: bras., Colombo, v. 39. e20/902043, Special issue. p. 1-768. 2019

659

660 XXV IUFRO World Congress Forest Research and Cooperation for Sustainable Development

enzymatic activities involved in OM decomposition and we compared the community level physiological profiles ( C L PP ) o f the soil microbes in WTH and SOH

plots. WTH decreased enzyme activities and catabolic potential of the soil microbial community. Furthennore, these negative effects on soil functional diversitv

were mainly observed below the 0-5 cm layer (5- I O and 1 0-20 cm), suggesting that WTJ I can be harmful to the soil health in these plantations.

Carbon sequestration and soil fertility in dryland

Acacia Senegal

plantations of varying age in Sudan

Wa_(c, .. ·/baker'. Fiw,k Berninger'. Gustavo Sai:;. Mike Starr'

'Univcrsi/J' of Kharlvwn. Khartoum, Suda11: 'U11iversity of Eastem Finland, Kuvpio, Fi11land; ; Imperial College Londo11. Ascol, United Ki11gdo111: 1_U11iversiry of Helsinki. Helsinki, Finland (wafaadam59@yahoo.co111;frank.beminger@11e(ji: g.sai:@i111perial.ac.11k; 111ike.slarr@helsinkiji)

A frican drylands are extensively degraded as indicated by reduced soil organic carbon (SOC) contents. Restoration through management practices that i ncrease

tree cover can be expected to i ncrease SOC contents and soil fertility. We investigated the potential or

Acacia se11�gal

trees for i ncreasing SOC and i mproving

soil fert ility at two siks in Sudan. Biomass C and SOC stocks. contribution or trees and herbs to SOC. soil nutrient (N, P, available P, K, exchangeable K)

contents and potential N, fixation by

A. senegal

in plantations of vary ing age (7 to �4 years) and in adjacent grasslands were determined. Total biomass C

stocks i ncreased with plantation age. Whik most of this increase was due to the trees, the ground vegetation C stock also increaseJ (facilitation effect). SOC

stocks (0-50 cm) increased with plantation age and were greater than in the grasslan

d

s

.

o I 3C part itioning values indicated that the age-related increase in SOC

stocks was derived not only fn>m the acacia trees but also from an i ncrease in ground vegetation biomass. While soil concentrations of the studied nutrients

were relatively low, they were positively correlated to SOC concentrations, highest in the topsoil (0- 1 0 cm) and increased with plantation age - all indicating

the importance of SOC to soi l ferti l ity High acacia foliage i5 1 5N values indicated that N, fixation was not an important contributor to soil N. Our findings

showed that increasing tree cover in Africnn drylan<ls can i ncrease SOC stocks and thereby improve soil fertil i ty for the benefit of local communities besides

sequestering atmospheric CO,.

Role of nitrogen ,1vailability on enhancing soil carbon sequestration in typical subtropical planted forests in Southern China

Shirong liu1_{. H11i IVi111g'}

'Chinese Academy of Fvres11v. Beiji11g, China; 'Institute of Forest Ecolog:,; £m·iron111e111 and Pro1ectio11. Chinese Academy of Forestry,; Beijing, China

{li11sr@cafac.cn; wangh11i@cafac.cn)

Planted forest ecosystem is becoming a key component o f the China's forest resources and timber storage and plays a key role in the context of potential carbon

( C ) sequestration and sustninable forest management. Information on the ef

f

ects of tree species compositi,m and d iversity on soil nitrogen (N) ovailabilit� and

organic carbon (C l sequestration remains l imited. The investigation and Jong-term manipulation experiment were cnll'ied our in typical subtropical planted

forests. Soil under Eucalyptus mixed with N

2

-fixer accumulated more soil organic C anJ N, and hod lower CO, emission than in pure stands by i ncreasing total

organic C and microbial biomass C. as well as through increased soil microbial community diversity and abundance. SOC and stocks in the Pinus massoniana

and Castanopsis hystrix mixeJ plantation were higher than in P 111asso11ia11a monospecific plantation

.

The odmixing with the higher-quality C. hyslrix litter

hastened mass loss for recalcitrant C chemical compositions and nutrient return of coni fer litter. Our results also showed that tree species mixture significantly

altered the soi l bacterial communirv composition and strncrnre, compared "·ith single-species plantations. The C

ratios of soil and l inerfall. TOC, H-l-N,

li nerfall mass and N03-N were key factors af

f

ecting the soil microbial community. There was a negative relationship bet\\·een SOC mineralization rates and

the abundance of K strategists and a positive relationship for r-srrategists These results indicateJ that N availability plays an i mportant role on enhancing SOC

sequestration through changing soil microbial co111111unity co111position in subtropical plamations.

Forest management strategics to safeguard water supply in karst regions under climate change

Klaus Ka1:::ensteiner

1

'l11stil11/e of Forest Ecolog>, University ()j'Na111ral Resources and Li(e Scie11ces, Vie11na (BOKU). Vie1111a, Austria {kla11s.kat:enslei11er@bok11.ac.al)

Worldwide. karst aquifers developed on calcareous bedrock are important sources of drinking water. Large karst areas of the montane and subalpine vegetat ion

belts in the Calcareous Alps are dominated by forests. The increasing frequencies anJ intensities of d isturbances. portly a consequence of cl imate change, may

alter the water storage. fi ltering and buf

f

ering capacity of forest ecosystems. thereby threatening the continuous provision or pristine water. Safeguarding water

supply from karst regions therefore requires the adaptation of forest management strategies. In the presentation. forest management anJ disturbance effects upon

soil condition and water quality in karst regions are discussed based on case studies fro111 the Alps. Stabi l ity- and vulnerabi l i ty- indicators o f karst systems and

its subsystems, from tree species, the vadose zone, in particubr soils, to karst water, are i ncorporated in a conceptual framework for adaptive forest management

strategies in view of \\·ater protection.

Tcor de carbono c nitrogcnio no solo cm fun�iio da aduba�iio cm um sistcma de intcgra,ao Lavour:1-Pccu:1ria-Florcsta c Plantio

Dircto

l.11cia111: Cristina La::::.::::.ari11

1

_{, ./11/iano Coruli Con,/!, Correc/, Ira(: Amaral G111.:rrini}

_'

_{. P£111/o Hi:nt::::.}

1

1Unesp,

Boructt/11,

Bra::il: ;Embrapa Suinos e Aves, Concrirdia,

Bncil:

i/FC,

Co111:6nlia.

Rra:.il

(/

u

ci

a

ne!t

c::::.

arin

'

{

�1111c

.

hr:

j

ulw

11

0.corre,r(�t)e

m

b

r

a

p

a.

br

:

igue1ri11i@(ca.1111esp.br: p<111/o.hent:fj}ifc.edu.br)

A pratica Je adubar;5o, quando necess:irio, promove ganho de produt,vidade ate tres vaes maior em comparar;5o a sua ni\o ado<;5

o

.

0 uso de t'enilizantes

orgfo,cos po<le resultar em ganhos econom,cos e ambientais, potencialtzando a di\'ersidade Jo sistema. Este trabalho ob_1e1ivou arnl,ar o teor de carbon,, e

nirrogenio no solo no sistema de produ<;5o integrai;iio Jovoura-pecu:iria-lforesta

( iLPF

I

e

plamio direto i PD I apos 3 anos com fertil izantes organicos ou minerais.

O experimento foi con<luz1do no municipto de Concc\rdia-SC'. on<le o dehneamento experimental foi blocos casualiza<los. corn 3 repeti<;i\es. em fatorial 2 x 4,

sendo dois t ip,>s de sistemas de pro<lui;iio ( l LPF e PD) em interar;5o corn tres tipos de fertilizantes t dejeto de suinos. cama de aves e mineral) e o controle t sem

adubai;iiol. As amostras de solo foram coletas ate J OO cm, e analisadas atraves do analisador elernentar (CNHOS

i

.

Niio hou,·e eteito do adubar;ao sob o teor de

carb,mo nos diferentes camadas para o s1ste111a I LPF. enquanto que para o PD houve diferen<;n para a adubar;5o coma de aves e mineral nas camadas superficiais.