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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso P.De Donato M.-P.Turpault INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly *** experiment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim was to identify potential nutritional consequences of droughts for *** nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree *** calcium(Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

Community structure of Lumbricidae in beech woodland of the Bieszczady National Park, Southeast Poland

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Pedosphere 2021年第3期31卷 391-397页

作者： Anna MAZUR-PĄCZKA Grzegorz PĄCZKA Joanna KOSTECKA Kevin R.BUTT Marcin JAROMIN Mariola GARCZYŃSKA Agnieszka PODOLAK University of Rzeszów Faculty of Biology and AgricultureDepartment of Natural Theories of Agriculture and Environmental Education1a Cwiklinskiej St.Rzeszów 35-959Poland University of Central Lancashire Forensic and Applied SciencesPreston PR12HEUK Rzeszów University of Technology Faculty of ChemistryDepartment of Biotechnology and Bioinformatics6 Powstancow Warszawy AvenueRzeszów 35-959Poland

As ecosystem engineers,earthworms play a key role in the soil ***,due to increasing anthropogenic pressure,soil organisms,including earthworms,are being threatened by habitat *** this study,we undertook a qualitative and quantitative investigation of earthworms of the family Lumbricidae in four types of Carpathian beech woodland(Fagetum carpaticum),characterized by their understory vegetation(I,*** drymejae;Ⅱ,***;Ⅲ,***;and IV,***),in the Bieszczady National Park(Eastern Carpathians,Southeast Poland).At each investigated site,soil monoliths(25 cm×25 cm×25 cm)were examined by hand *** were expelled from deep soil layers using a weak formalin solution(0.4%).Depending on the phytocoenosis,7 species of Lumbricidae were identified at each of the sites I,Ⅱ,andⅢand 10 at site *** IV(***)differed significantly(P<0.05)from the other three sites with respect to earthworm biomass(59.71±39.53 g m^(-2))and the Shannon-Wiener diversity index(0.52±0.12).Although present three decades ago,the deep-burrowing species Octodrilus transpadanus and the litter-dwelling species Dendrobaena octaedra were not found at site IV in the present *** suspect that these two species may have been displaced by the invasive Lumbricus terrestris,which was not found at the same site in the *** observations warrant further investigation to verify the predicted effects of an invasive earthworm,including the potential effects on soils and other fauna and flora,which have been documented in numerous countries.

关键词： beech forest earthworm invasive species Shannon-Wiener diversity index species diversity species dominance

Does tree species composition control the soil carbon stocks of the Hyrcanian forest in the Northern Iran?(A case study in Guilan province,Iran)

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Journal of forestry Research 2014年第1期25卷 143-146页

作者： Vilma Bayramzadeh Department of wood Sciences Faculty of Agriculture and Natural ResourcesKaraj BranchIslamic Azad University

This work studied the effects of tree species composition on soil carbon storage in five mixed stands dominated by oriental beech and grown in the western Caspian region in Guilan province, called Astara, Asalem, Fuman, Chere and Shenrud. The thickness of the litter layer, soil characteristics, tree composition and percentage of canopy coverage were measured in each stand. Total soil organic carbon differed significantly by stand. Total （organic） carbon stores at Fuman, which had the lowest tree species richness with 2 species and least canopy coverage （75%）, were significantly （p〈0.05） higher than at other locations. Carbon stor-age in topsoil （0-10 cm） was significantly lower in Shenrud, which had the highest tree species richness with 5 species and highest canopy cov-erage （95%）. The high percentage of canopy coverage in Shenrud proba-bly limited the conversion of litter to humus. However, in the second soil layer （10-25 cm）, Asalem, with high tree species richness and canopy coverage, had the highest carbon storage. This can be explained by the different rooting patterns of different tree species. In the Hyrcanian forest. According to the results, it can be concluded that not only tree composi-tion but also canopy coverage percentage should be taken under consid-eration to manage soil carbon retention and release.

关键词： beech forest canopy coverage soil carbon stocks tree composition

The relationships between selected soil properties and caesium-137 identify organic carbon,nitrogen and water soluble phenols as indicators of soil erosion processes in different forest stands

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Journal of forestry Research 2021年第6期32卷 2589-2598页

作者： Federico Romeo Paolo Porto Carmelo Mallamaci Adele Muscolo Department of Agriculture Mediterranea UniversityFeo di Vito89122Reggio CalabriaItaly

In the last few decades,the use of environmental radionuclides,particularly caesium-137(^(137)Cs),represented one of the most valid methods for estimating soil ***,the cost associated with the use of the equipment needed for radiometric analyses is still high and,for this reason,finding more easily measurable indicators can be *** is a strong correlation between^(137)Cs,organic carbon(OC),nitrogen(N)and water soluble phenols(WSP)exists,indicating the latter parameters as possible early indicators of soil *** on the above assumptions,the main purpose of this work is to identify specific soil chemical parameters able to indicate early triggering of soil ***,several soil parameters such as pH,electric conductivity(EC),WSP,OC,N and C/N have been evaluated against^(137)Cs and on a comparative *** addition,since the rate of soil erosion depends on the degree of coverage and canopy structure,two different tree species(Pinus nigra laricio *** Fagus sylvatica L.)have been considered in this contribution in which ten different scenarios of forest management have been *** results show that the reduction in tree cover of managed sites triggers erosion and nutrient loss *** has been observed that the loss of^(137)Cs,compared to the control areas,is closely correlated with those of WSP,OC and *** parameters(WSP,OC and N),more easily assessable,can be a valid tool to understand easily,triggering of erosive phenomena.

关键词： ^(137)Cs Erosion indicators forest thinning beech forest Pine forest

Long-term effect of fire on herbaceous species diversity in oriental beech (Fagus orientalis Lipsky) forests in northern Iran

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forestry Studies in China 2012年第4期14卷 260-267页

作者： Mohammad Naghi ADEL Hassan POURBABAEI Ali OMIDI David POTHIER Department of forestry Natural Resources FacultyUniversity of Guilan Department of forestry Natural Resources Office Centre d'étude de la forêt (CEF) et Département des sciences du bois et de la forêt Pavillon Abitibi-Price2405 rue de la TerrasseUniversité Laval

We studied the long-term impacts of natural burning on herbaceous species diversity 37 years after a fire occurred in the Roudbar forests of Guilan Province, northern Iran. Numerous studies have examined short-term changes in understory vegetation following wildfire; however, very few long-term studies are available or changes inferred from retrospective studies based on chro- nosequences. For this study, 170 ha of forest （85 ha, burned areas; 85 ha, unburned areas） were surveyed. Because the 1000 m2 plots were too large for detailed measurements of herbaceous species, we determined a sub-sample size according to the Whittaker＇s nested plot sampling protocol and minimal areas method. Hence, sub-plots of 32 m2 were used for herbaceous species measurements, which consisted of percent cover of each species based on the Domin criterion. We measured plant diversity （Shannon-Wiener index）, spe- cies richness （Margalef＇s index）, and evenness （Smith-Wilson index）. Mean percent cover, together with diversity, richness and even- ness, increased markedly in burned areas compared to unburned controls. This suggests that the biodiversity of these forests could be restored within 37 years after fire. However, the abundance of invasive species such as Rubus fruticosus and Bromus benekenii increased significantly in burned areas, but these could be controlled by relevant silvicultural operations.

关键词： fire diversity richness evenness beech forest northern Iran