Increased Atmospheric CO 2 : Chemical Changes in Decomposing Sweet Chestnut (Castanea sativa) Leaf Litter Incubated in Microcosms under Increasing Food Web Complexity

Oikos ◽  
1996 ◽  
Vol 76 (3) ◽  
pp. 553 ◽  
Author(s):  
Marie-Madeleine Coûteaux ◽  
Lucile Jocteur Monrozier ◽  
Pierre Bottner ◽  
Marie-Madeleine Couteaux
1998 ◽  
Vol 6 (1) ◽  
pp. 1-12 ◽  
Author(s):  
M Francesca Cotrufo ◽  
Björn Berg ◽  
Werner Kratz

There is evidence that N concentration in hardwood leaf litter is reduced when plants are raised in an elevated CO2 atmosphere. Reductions in the N concentration of leaf litter have been found for tree species raised under elevated CO2, with reduction in N concentration ranging from ca. 50% for sweet chestnut (Castanea sativa) to 19% for sycamore (Acer platanoides). However, the effects of elevated CO2 on the chemical composition of litter has been investigated only for a limited number of species. There is also little information on the effects of increased CO2 on the quality of root tissues. If we consider, for example, two important European forest ecosystem types, the dominant species investigated for chemical changes are just a few. Thus, there are whole terrestrial ecosystems in which not a single species has been investigated, meaning that the observed effects of a raised CO2 level on plant litter actually has a large error source. Few reports present data on the effects of elevated CO2 on litter nutrients other than N, which limits our ability to predict the effects of elevated CO2 on litter quality and thus on its decomposability. In litter decomposition three separate steps are seen: (i) the initial stages, (ii) the later stages, and (iii) the final stages. The concept of "substrate quality," translated into chemical composition, will thus change between early stages of decomposition and later ones, with a balanced proportion of nutrients (e.g., N, P, S) being required in the early decomposition phase. In the later stages decomposition rates are ruled by lignin degradation and that process is regulated by the availability of certain nutrients (e.g., N, Mn), which act as signals to the lignin-degrading soil microflora. In the final stages the decomposition comes to a stop or may reach an extremely low decomposition rate, so low that asymptotic decomposition values may be estimated and negatively related to N concentrations. Studies on the effects of changes in chemical composition on the decomposability of litter have mainly been made during the early decomposition stages and they generally report decreased litter quality (e.g., increased C/N ratio), resulting in lower decomposition rates for litter raised under elevated CO2 as compared with control litter. No reports are found relating chemical changes induced by elevated CO2 to litter mass-loss rates in late stages. By most definitions, at these stages litter has turned into humus, and many studies demonstrated that a raising of the N level may suppress humus decomposition rate. It is thus reasonable to speculate that a decrease in N levels in humus would accelerate decomposition and allow it to proceed further. There are no experimental data on the long-term effect of elevated CO2 levels, and a decrease in the storage of humus and nutrients could be predicted, at least in temperate and boreal forest systems. Future works on the effects of elevated CO2 on litter quality need to include studies of a larger number of nutrients and chemical components, and to cover different stages of decomposition. Additionally, the response of plant litter quality to elevated CO2 needs to be investigated under field conditions and at the community level, where possible shifts in community composition (i.e., C3 versus C4 ; N2 fixers versus nonfixers) predicted under elevated CO2 are taken into account.Key words: climate change, substrate quality, carbon dioxide, plant litter, chemical composition, decomposition.


1999 ◽  
Vol 64 ◽  
Author(s):  
D. Van den Meersschaut ◽  
B. De Cuyper ◽  
K. Vandekerkhove ◽  
N. Lust

Natural  stand changes in the forest reserve of Liedekerke were analysed during the  period    1986-1996, using a permanent grid of circular plots. The monitoring  concentrated on natural    changes in species composition, using stem number and basal area as  indicators, and changes    in spatial distribution and colonization capacities of trees and shrubs,  with special interest in the    competition between exotic and indigenous species. After only a decade of  monitoring important    natural changes in the woody layer were detected. The pioneer forest is  gradually maturing    through self-thinning processes and shifts in species composition. The  overall stem number    decreased with 33.6%, while the basal area increased with 20.9%. Birch (Betula pendula/    pubescens) and indigenous oak (Quercus robur/petraea) remained  dominant. More tolerant    exotic species, like red oak (Quercus rubra) and sweet chestnut (Castanea  sativa), are slowly    increasing their share in the species composition and expanding their  range. Pioneer species on    the other hand, like aspen (Populus tremula), willow (Salix  capreaicinerealaurita), alder buckthorn    (Frangula alnus) and  common (Alnus glutinosa)  and grey alder (A. incana),  strongly declined.    Black cherry (Prunus serotina) seems to be slowly invading the forest due to its  massive    natural regeneration. Strong competition may be expected especially from  rowan ash (Sorbus    aucuparia), which showed similar regeneration  and colonization capacities. Elder (Sambucus    nigra) dramatically extented its range, though  its share remains marginal. Beech remained absent    most probably due to the lack of mature trees in the vacinity of the  forest. Finally this    change detection allowed that general predictions could be made on the  future natural development    and composition of this forest reserve, which could serve forest management  decisions.


2021 ◽  
Vol 494 ◽  
pp. 119320
Author(s):  
Marco Conedera ◽  
Patrik Krebs ◽  
Eric Gehring ◽  
Jan Wunder ◽  
Lisa Hülsmann ◽  
...  

Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1538
Author(s):  
Ana Teresa Alhinho ◽  
Miguel Jesus Nunes Ramos ◽  
Sofia Alves ◽  
Margarida Rocheta ◽  
Leonor Morais-Cecílio ◽  
...  

The sweet chestnut tree (Castanea sativa Mill.) is one of the most significant Mediterranean tree species, being an important natural resource for the wood and fruit industries. It is a monoecious species, presenting unisexual male catkins and bisexual catkins, with the latter having distinct male and female flowers. Despite the importance of the sweet chestnut tree, little is known regarding the molecular mechanisms involved in the determination of sexual organ identity. Thus, the study of how the different flowers of C. sativa develop is fundamental to understand the reproductive success of this species and the impact of flower phenology on its productivity. In this study, a C. sativa de novo transcriptome was assembled and the homologous genes to those of the ABCDE model for floral organ identity were identified. Expression analysis showed that the C. sativa B- and C-class genes are differentially expressed in the male flowers and female flowers. Yeast two-hybrid analysis also suggested that changes in the canonical ABCDE protein–protein interactions may underlie the mechanisms necessary to the development of separate male and female flowers, as reported for the monoecious Fagaceae Quercus suber. The results here depicted constitute a step towards the understanding of the molecular mechanisms involved in unisexual flower development in C. sativa, also suggesting that the ABCDE model for flower organ identity may be molecularly conserved in the predominantly monoecious Fagaceae family.


Author(s):  

Abstract A new distribution map is provided for Gnomoniopsis smithogilvyi Shuttleworth, Liew and Guest. Sordariomycetes: Diaporthales. Hosts: sweet chestnut (Castanea sativa) and other chestnut species. Information is given on the geographical distribution in Europe (France, Greece, Italy, mainland Italy, Sardinia, Slovenia, Spain Switzerland, UK, England and Wales), Asia (India, Jammu and Kashmir), Oceania (Australia, New South Wales, Victoria, New Zealand).


2017 ◽  
pp. 79-82
Author(s):  
Gabriella Kovács ◽  
László Radócz

The most destructive pathogen for the European chestnut is the blight fungus Cryphonectria parasitica (Murr.) Barr. The spread of the fungus was very fast in Europe within a few decades in the second half of the past century. During the tree-health checking in the chestnut andwalnut plantation in Romania, Hargita county, next to Homoródkarácsonyfalva village, we especially concentraded on the signs of blight disease occurrence. The grove is laying on a western slope, under a pine forest. This favourable geographical space protects it not only from pathogen attacts, but it has a special, mild microclimate for nut and chestnut trees. The European chestnut could be a valuable member of local forests, opening a new perspective under conditions of climate changes.


Author(s):  
Murat SARGINCI ◽  
Oktay YILDIZ ◽  
Doğanay TOLUNAY ◽  
Bülent TOPRAK ◽  
Şule TEMÜR

This study aimed to estimate leaf litter decomposition rates in eastern beech (Fagus orientalis Lipsky) and sweet chestnut (Castanea sativa Mill.) mixed stands in Düzce-Akçakoca, located in the Western Black Sea Region of Turkey. The sampling areas represent four different elevations and two aspects at each elevation. Amounts of annual beech and chestnut litter fall were estimated as 5.19 Mg ha-1 and 4.61 Mg ha-1, respectively. Litter decomposition was examined over five time periods (0.25, 0.50, 1.25, 2.25, and 4.25 years) by using the litter bag method. The amount of remaining beech leaf litter mass was found to be 1.1, 1.2, 1.2, 1.4, and 1.3 times greater than the amount of chestnut leaf litter, respectively. However, estimated values for the decomposition rate-constant (k) of chestnut for all time periods were found to be approximately 1.5 times greater than those of beech leaf litter. Litter in beech stands decomposed more rapidly at higher elevations during the first year, but at lower elevations in the second year, likely due to increased temperature and precipitation for the corresponding years. Leaf litter in chestnut stands decomposed more rapidly at lower elevations in the second and fourth year, reflecting higher precipitation of those years.


Sign in / Sign up

Export Citation Format

Share Document