644 XXV IUFRO World Congress Forest Research and Cooperation for Sustainable Development
logging resiuue piles of different tree species, and control plots wit·hout logging residues, were subsequentlv established. Effects of logging residue piles were monitored; leaching as N concentrations in soil percolating water. and N ,0 emissions with closed chamber technic o,w two growing season. Soil denitrification activity and the contribution of nitrification anu Jenitrification to N,0 -production were determined in laboratory experiment. as well as nitrogenase activity in the logging residues. Logging residue piles increased nitrate \NO;-N) concentrations in soil percolation water In addition logging residues piles tended to stimulate N,O Auxes although in general the fluxes were low. Logging residues showed some nitrogenase activitv. Currently we study the effects oflarge logging resiuue sror:1ge piles on N mobilization and losses.
Nitrogen addition to nitrogen rich forests: effects on soil nitrogen content Lors Hogbom1, Ulf Sikstrom'
171,e Forestry R.:search fnstilllte of Sweden. Uppsala, Sweden; '71,e Forest,y Research /11slit11te of Sweden, Uppsala, S,reden (lars.hogbo111@skogforsk.se; 11l{si/istro111@skogforsk.se)
Human activities have altered the pools and Auxes of nitrngen (N) in the forest soil. In southern Sweden. a substantial deposition of air-borne N pollution has been going on for several decades. During the most recent decades up to 15-25 kg ha·' yr' of has been deposited in forested areas. At present the major part of deposited is retaineu in the soil. However, there are concerns that the input of N inro forest e,osystems will lead to so called N-saturation. Generally, the N cycle in Swedish forests is closed and the small amount of leaching rhat occurs is mainly of organic N. However, quite high leaching of inorganic N has occasionally been observed in some areas. especially in soutlm·estern Sweden. In order to simulate eftects of an elevated , deposition a series or experiments was established in forest in the southern pan of Sweden including annual addition of low N doses (20 kg h,r' y,-1). The experiments were established in stands of two different sik productivity classes within two regions with differences in N deposition. The main aim of the project is to study effects on several 1·orest ecosystem properties of lo\\· , dose audition as well as of conventional practical forest leriil ization. Here we report on changes in soil N content in the upper soil layer following addition or low-dose N application by a series or soil samplings, in order to estimate how much of the added N is retained there. l s there a niche complementarity for nitrate uptake among savannah shrub and tree species in a very deep Brazilian soil'? Rafael Pinheira1. Jeon-Paul Locfou11, lrae G11errini1, Livia Alo', Jean-Pierre Boui!fet"
1Faculdade de Cici11cias Agro116111icas de Botucatu/UNESP. Montpelfie1: Brasil; 'Faculdade d.: Cie11cias .4gron6micas de Botucat,v'UNESP. Botucat11. Brasil: 'UJ-!R Eco&Sols -CIR4D. Mon1pelfie1: France; 'Escolo S11perior de Agricult11ra "Lui= de Q11eiro= ··, Universidade de Siio Paulo, Piracicoba, Brasil
(ra/amic _ I O@hotmail.com: locla11@cirad.fr: iguerri11i@fca.1111esp.br: livialmi=i@yahoo.com. hr: jphoui/let@cirad.fr)
Belowground niche complementarity between deep-rooted and shallow-rooted species in mixeu forests may result in a more complete exploitation of soil resources than in monocultures. Our study aimed to assess I) the maximum distance (horiwntally and venically) where the fine roots from common Cerrado species take up mobile nutrients in Jeep Ferralsols. and 2J whether there is a niche complementaritv in nitrate uptake between some Cerrado species. Our study was carried out in a closed-canopy forest with dense woody understorv (cerradao) at Bauru (Sao Paulo State); !SN-NO,- was injected at the onset of urv and rainy seasons at 6 depths (0.1. 1.5, 3. 6. 9 and 12 m) with 3 plots per depth and a distance> 50 m between each injection ·depth. Leaves were sampled 4 months afier tra,er injection in 3 rrequent spe,ies in each plot located at 4 intervals of distance from the tracer injection point l0-2 m; 3-6 m; 7-IO m; c: 12 m) and I SN atom'�/. was determined. Great differences in I SN tracer uptake between the studied species showed a niche complementarity in this native savannah. Xy/opia
amnwtico exhibited a strong !SN uptake at 6 m of depth, irrespective of the season. This species seems to exploit a much larger soil ,·olume than the others, both vertically and horizontally ( I SN taken up at 5 m from the injection point). Miconia albicans and Coussarea hydrangeifolia showed similar behaviours,
with a strong I SN uptake in the topsoil and down to 1.5 111 depth. within 2 m from the injection point.
Litterfall production and litter decomposition at several forests considering climate and litter quality in South Korea By11ng Boe Park''. Si Ho Han', Aji-ojo Rahman'.· Huong Thi Thur Dao 1, Jeong Min Seo', Woo Bin ru,m1. A 1111g A ung1, Ji )'oung An'·'. Hwa Ja Hy1111'.
Hvung-Soon Choi5
'Ch1111gna111 Natio11al U11i1·ersi1y, Daejeon, Korea. Republic of; 'Korean Society of Forest Sicence, Seo11I, Republic of Korea: 'Kyoto Unircrsif)\ Kyoto, Jopa11: 'Warm Temperate and Subtropical Forest Research Cente1: Seogwipo, Republic of Korea: 'Forest Conservation Deportment. Seoul, Republic of Korea (bbpark@c11u.ac.kr; b11ple11ru111lu111@rn11.ac.kr: aji-oja.r IO@g111oil.cl)l11: tl111vl111ong. J 50./95@g111ail.cv111; j111seoJ@11a,-e1:co111; dbsdnqls95@nave,: co111: baga11c111ng 7 77@g111ail.co111; anji_m1111g. 'e@kvoto-11. acjp; viola 19 7 -l@korea.kr: f01gc11e@korea.kr)
We investigated litterfall production and litter decomposition, which are the major pathway for carbon anu nutrients m forest ecosystem. at a couple or different
forests considering climate and litter qualiry. Litterfall production has heen ohserved at several deciJuous or evergreen forests for about ten years across temperate and sub-tropical region in Korea. Leaf liner translocation experiments have been carried out covering 14 °C- 17 °C range of mean annual temperature and 1,200 mm - I .400 mm range of mean annual precipitation. The results showed that total litterfall was much higher at evergreen broad leaf forest (903 gm-' yr') than others (698 gnY' y,-1), but was annually fluctuated. Litterfall production in evergreen forest was the highest at spring season, but for deciduous lorest fall season was the maximum. Liner decomposition follows the similar decomposition trend, but decomposition was much faster in forests which has higher temperature during winter season. Litter decomposition was diverse by litter quality and average temperature during winter season. Although the effect ,,f lo rest type, climate. and litter quality on litter production and liner decomposition is complex. this experiment will give an overview ho\\· these factors in11uence on carbon and nutrient cvcling by mouirying litterfall production and litter decomposition.
Post-logging management and soil type can affect litter layers in Amazon tropical forest?
Fernando Cescirio1fl!>. Fabiano Ba/Jeiro:. Lucas Ala=:e(
1Unfrcrsidade Federal Fluminense. Rio de Janeiro. Brasil; :Embrapa .5olvs, Rio de Janeiro. Brosi; 3Embrapa .·lma:6nia Ocidenlal. Pani, Brasil
(fenu111dovicirm.:es,1rio«_l}gmail. com: fahiono.bal,i:iroifi]embrapa. br: f Hcas. mcc:ei@embrapa.bi)
Litter is one of the mam carbon and nutrient pools m the terrestrial ecos,·stem Howe\'er. the litter structural organization and the charactenst,cs or 11s horizons. especially in hunn1s forms perspective, tha1 l!nables us to understand the topsoil processes or tropical loresl c-..;osystcm fun..;til1ning. are not well understood. \Ve hvpothesize that the soil class aff
ects the soil macro anu microbial acti,·itv and fertility, and thus the humus fonns horizons. Like,vise, the logging practices and the rroducer-de,omposer forest processes altering the decompos11ion rates and liner input was evaluated. We used morpho-fun,tional npproach (Zanella et al..2017) 10 describe the humus forms h,nizons on two different soil tvpes (Ferralsols and Gleysols). unda two post-logging practices of management (wirh
