scholarly journals Early vegetation recovery after the 2008-2009 explosive eruption of the Chaitén Volcano

2019 ◽  
Author(s):  
Ricardo Moreno-González ◽  
Iván A. Díaz ◽  
Duncan A. Christie ◽  
Rafael E. Coopman ◽  
Antonio Lara
Keyword(s):  
Organic Substrate ◽  
Tree Regeneration ◽  
Environmental Damage ◽  
Frugivorous Birds ◽  
Dead Trees ◽  
Biological Legacies ◽  
Standing Dead ◽  
Surrounding Areas ◽  
Species Specific ◽  
Blast Zone

AbstractIn May 2008, Chaitén volcano entered in eruptive process, one of the world largest eruptions in the last decades. The catastrophic event left different type of disturbance and caused diverse environmental damage distributed heterogeneously in the surrounding areas of the volcano. We went to the field to assess the early vegetation responses a year after the eruption, in September 2009. Particularly, we evaluated the lateral-blast disturbance zone. We distributed a set of plots in three disturbed sites, and one in an undisturbed site. In each of these sites, in a plot of 1000m2 we marked all stand tree, recording whether they were alive, resprouting or dead. Additionally, in each site 80 small-plots (~4m2) we tallied the plants regeneration, its coverage, and the log-volume. We described whether the plant regeneration was growing on mineral or organic substrate. In the blast-zone the eruption created a gradient of disturbance. Close to the crater we found high devastation marked by no surviving species, scarce standing-dead trees and logs, as well as no tree regeneration. On the other extreme of the disturbance gradient, the trees with damaged crown were resprouting, small-plants were regrowing and seedlings were more dispersed. The main regeneration strategy was the resprouting of trunks or buried roots, while few seedlings were observed in the small plots and elsewhere in disturbed areas. However, the assessment was too soon after the eruption and updated monitoring is required to confirm observed patterns. The main findings of this study are: i) a mosaic of pioneering-wind dispersed species, scattered survivors regrowing and spreading from biological legacies, and plant species dispersed by frugivorous birds, likely favored by the biological legacies; (ii) the early succession is influenced by the interaction of the species-specific life history, altitudinal gradient and the different intensity of disturbance.

scholarly journals Classification of Tree Species as Well as Standing Dead Trees Using Triple Wavelength ALS in a Temperate Forest

2019 ◽  
Vol 11 (22) ◽  
pp. 2614 ◽  
Author(s):  
Nina Amiri ◽  
Peter Krzystek ◽  
Marco Heurich ◽  
Andrew Skidmore
Keyword(s):  
Tree Species ◽  
Feature Selection Method ◽  
Silver Fir ◽  
Maximum Point ◽  
Individual Tree ◽  
Dead Trees ◽  
Multi Wavelength ◽  
Standing Dead ◽  
Standing Dead Trees ◽  
532 Nm

Knowledge about forest structures, particularly of deadwood, is fundamental for understanding, protecting, and conserving forest biodiversity. While individual tree-based approaches using single wavelength airborne laserscanning (ALS) can successfully distinguish broadleaf and coniferous trees, they still perform multiple tree species classifications with limited accuracy. Moreover, the mapping of standing dead trees is becoming increasingly important for damage calculation after pest infestation or biodiversity assessment. Recent advances in sensor technology have led to the development of new ALS systems that provide up to three different wavelengths. In this study, we present a novel method which classifies three tree species (Norway spruce, European beech, Silver fir), and dead spruce trees with crowns using full waveform ALS data acquired from three different sensors (wavelengths 532 nm, 1064 nm, 1550 nm). The ALS data were acquired in the Bavarian Forest National Park (Germany) under leaf-on conditions with a maximum point density of 200 points/m 2 . To avoid overfitting of the classifier and to find the most prominent features, we embed a forward feature selection method. We tested our classification procedure using 20 sample plots with 586 measured reference trees. Using single wavelength datasets, the highest accuracy achieved was 74% (wavelength = 1064 nm), followed by 69% (wavelength = 1550 nm) and 65% (wavelength = 532 nm). An improvement of 8–17% over single wavelength datasets was achieved when the multi wavelength data were used. Overall, the contribution of the waveform-based features to the classification accuracy was higher than that of the geometric features by approximately 10%. Our results show that the features derived from a multi wavelength ALS point cloud significantly improve the detailed mapping of tree species and standing dead trees.

Preadaptation and spatial effects on retention-tree survival in cut areas in Estonia

2008 ◽  
Vol 38 (10) ◽  
pp. 2616-2625 ◽  
Author(s):  
Raul Rosenvald ◽  
Asko Lõhmus ◽  
Andres Kiviste
Keyword(s):  
Natural Disturbance ◽  
Forest Edge ◽  
Forest Site ◽  
Spatial Effects ◽  
Forest Edges ◽  
Dead Trees ◽  
Tree Survival ◽  
Tree Retention ◽  
Standing Dead ◽  
Retention Trees

Survival of live retention trees is a key issue for stand-scale applications of natural-disturbance-based silviculture. We explored the survival of 3255 trees in 102 cut areas (mean size 2.3 ha) in Estonia for 6 years, focusing on spatial variation and preadaptation of the trees. Altogether, 35% of the trees died during the study period, contributing 4.4 m3 of downed dead trunks and 1 m3 of standing dead trees per hectare. The annual mortality rates declined over time. The main survival determinants were tree species (higher for hardwood deciduous trees), diameter (species dependent), position relative to forest edge (higher for trees near current or former forest edges), retention density (positive), and exposure (negative). The results suggest that (1) green-tree retention can effectively increase the abundance of large shade-tolerant trees, but it is equally important for producing deadwood; (2) larger individuals, former interior-forest trees near current forest edges, and preadapted trees in open conditions should be preferably retained; (3) there is no obvious necessity to modify tree-retention techniques for tree survival according to geographical region or forest site type.

scholarly journals Standing Dead Trees are a Conduit for the Atmospheric Flux of CH4 and CO2 from Wetlands

Wetlands ◽  
2017 ◽  
Vol 38 (1) ◽  
pp. 133-143 ◽  
Author(s):  
Mary Jane Carmichael ◽  
Ashley M. Helton ◽  
Joseph C. White ◽  
William K. Smith
Keyword(s):  
Atmospheric Flux ◽  
Dead Trees ◽  
Standing Dead ◽  
Standing Dead Trees

scholarly journals Resources of dead wood in the municipal forests in Warsaw

2015 ◽  
Vol 76 (4) ◽  
pp. 322-330 ◽  
Author(s):  
Konrad Skwarek ◽  
Szymon Bijak
Keyword(s):  
National Parks ◽  
Coarse Woody Debris ◽  
Forest Ecosystems ◽  
Dead Wood ◽  
Woody Debris ◽  
Forest Site ◽  
Natural Forests ◽  
Dead Trees ◽  
Standing Dead ◽  
High Degree

Abstract Dead wood plays an important role for the biodiversity of forest ecosystems and influences their proper development. This study assessed the amount of coarse woody debris in municipal forests in Warsaw (central Poland). Based on the forest site type, dominant tree species and age class, we stratified all complexes of the Warsaw urban forests in order to allocate 55 sample plots. For these plots, we determined the volume of dead wood including standing dead trees, coarse woody debris and broken branches as well as uprooted trees. We calculated the amount of dead wood in the distinguished site-species-age layers and for individual complexes. The volume of dead matter in municipal forests in Warsaw amounted to 38,761 m3, i.e. 13.7 m3/ha. The obtained results correspond to the current regulations concerning the amount of dead organic matter to be left in forests. Only in the Las Bielański complex (northern Warsaw) volume of dead wood is comparable to the level observed in Polish national parks or nature reserves, which is still far lower than the values found for natural forests. In general, municipal forests in Warsaw stand out positively in terms of dead wood quantity and a high degree of variation in the forms and dimensions of dead wood.

scholarly journals MENAKAR SIFAT INVASIF SPESIES AKASIA MANGIUM (Acacia mangium Willd.) DI HUTAN PENELITIAN DAN PENDIDIKAN BUKIT SOEHARTO

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Sutedjo Sutedjo ◽  
Warsudi Warsudi
Keyword(s):  
Acacia Mangium ◽  
Dead Trees ◽  
Standing Dead ◽  
Standing Dead Trees

 Akasia mangium (Acacia mangium Willd) bukan tumbuhan asli Kalimantan namun sejak puluhan tahun tumbuh berkembang pesat di berbagai wilayah Kalimantan termasuk Kalimantan Timur. Dikenal sebagai tumbuhan yang mampu tumbuh di lahan kritis sehingga pada awal tahun 1990-an dijadikan tanaman  reboisasi sekaligus pengendali alang-alang di wilayah kritis hutan penelitian dan pendidikan Universitas Mulawarman di Bukit Soeharto. Mengherankan, bahwa beberapa tahun taerkhir sebagian praktisi kehutanan dan reklamasi pascatambang merasa gamang menggunakan A. mangium, khawatir jika jenis tersebut akan benar benar menjadi spesies invasif.  Gejala untuk menolak bahkan menghindari  A. mangium sebagai komoditas kehutanan terutama sebagai jenis pengendali lahan kritis mulai meluas. Untuk mengetahui seberapa benar anggapan Acacia mangium sebagai jenis invasif maka dilakukan evaluasi dengan melakukan analisis vegetasi terhadap 3 ha tegakan hutan A. mangium yang ditanam di Bukit Soeharto sebagai uji petik yang saat sekarang telah berumur sekitar 25 tahun. Hasil evaluasi membuktikan bahwa jumlah tanaman per ha (kerapatan) pohon A. mangium menurun (kurang dari jumlah saat ditanam atau sekitar 800 individu/ha). Jumlah yang menurun itupun cenderung mengelompok. Sebagian pohon bahkan ditemukan dalam kondisi mati generasi (standing dead trees). Sementara itu jumlah spesies pohon setempat (local trees species) juga mulai muncul di antara tegakan A.mangium. Dengan demikian terbukti  bahwa A. mngium bukanlah tipe invasif  yang sesungguhnya dan tidak ada alasan utuk menolak penggunaannya sebagai tanaman pengendali lahan kritis selama potensi ancaman terjadinya kebakaran lahan hutan dapat dicegah.

scholarly journals The structure of forest stands in the Tatra National Park: The results of 2016–2017 inventory

2019 ◽  
Vol 80 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Jan Bodziarczyk ◽  
Jerzy Szwagrzyk ◽  
Tomasz Zwijacz-Kozica ◽  
Antoni Zięba ◽  
Janusz Szewczyk ◽  
...  
Keyword(s):  
Picea Abies ◽  
Fagus Sylvatica ◽  
National Park ◽  
Forest Stands ◽  
Protection Zone ◽  
Dead Trees ◽  
Standing Dead ◽  
Elevation Zone ◽  
Standing Dead Trees ◽  
Tatra National Park

Abstract The composition and structure of forest stands in the Tatra National Park were examined using data gathered in 2016 and 2017 from 617 circular sample plots (0.05 ha each). The diameter at breast height of all living trees, standing dead trees, snags, and wind throws was measured along with diameters and lengths of fallen logs within the plot boundaries. Tree height was measured for all living trees within the core (0.01 ha) of the sample plots. Using the obtained data, height-diameter curves were calculated for all major tree species and in the case of spruce, the height-diameter relationships were also calculated separately for each of the three elevation zones (up to 1200 m, between 1200 and 1400 m, above 1400 m). For each elevation zone and park protection zone, we also determined the volumes of live and dead trees. The volume of living trees in the Tatra National Park amounted to 259 m3/ha, which was higher than the volume of dead trees (176 m3/ha). Snags constituted the largest part of the dead wood whilst over 97% of the standing dead trees were spruce Picea abies. Among living trees, the share of spruce ranged from 81% in the low elevation zone to 98% in the middle zone. Other significant species in the lower zone were Abies alba (11%) and Fagus sylvatica (4.5%), while in the middle and upper elevation zones only Sorbus aucuparia occurred in significant numbers. Furthermore, in the lower elevation zone, Fagus sylvatica was the only species displaying significantly higher volumes in the ‘strict protection’ zone compared to the other park areas. In the ‘landscape protection’ zone, Picea abies was the most dominant species and the share of other species in the lowest elevation zones calculated based on tree density was smaller than calculated based on tree volume, indicating problems with stand conversion from spruce monoculture to mixed forest.

Decay patterns and carbon density of standing dead trees in California mixed conifer forests

2015 ◽  
Vol 353 ◽  
pp. 136-147 ◽  
Author(s):  
Stella J.M. Cousins ◽  
John J. Battles ◽  
John E. Sanders ◽  
Robert A. York
Keyword(s):  
Conifer Forests ◽  
Carbon Density ◽  
Mixed Conifer ◽  
Dead Trees ◽  
Mixed Conifer Forests ◽  
Standing Dead ◽  
Standing Dead Trees

scholarly journals Tree structure and richness in an Atlantic Forest fragment: distance from anthropogenic and natural edges

2009 ◽  
Vol 33 (6) ◽  
pp. 1123-1132 ◽  
Author(s):  
Maíra Taquiguthi Ribeiro ◽  
Flavio Nunes Ramos ◽  
Flavio Antonio Maës Dos Santos
Keyword(s):  
Atlantic Forest ◽  
Rio De Janeiro ◽  
Basal Area ◽  
The State ◽  
Forest Fragment ◽  
Dead Trees ◽  
Tree Communities ◽  
Standing Dead ◽  
Total Study Area ◽  
Tree Branch

Approximately 7.2% of the Atlantic rainforest remains in Brazil, with only 16% of this forest remaining in the State of Rio de Janeiro, all of it distributed in fragments. This forest fragmentation can produce biotic and abiotic differences between edges and the fragment interior. In this study, we compared the structure and richness of tree communities in three habitats - an anthropogenic edge (AE), a natural edge (NE) and the fragment interior (FI) - of a fragment of Atlantic forest in the State of Rio de Janeiro, Brazil (22°50'S and 42°28'W). One thousand and seventy-six trees with a diameter at breast height > 4.8 cm, belonging to 132 morphospecies and 39 families, were sampled in a total study area of 0.75 ha. NE had the greatest basal area and the trees in this habitat had the greatest diameter:height allometric coefficient, whereas AE had a lower richness and greater variation in the height of the first tree branch. Tree density, diameter, height and the proportion of standing dead trees did not differ among the habitats. There was marked heterogeneity among replicates within each habitat. These results indicate that the forest interior and the fragment edges (natural or anthropogenic) do not differ markedly considering the studied parameters. Other factors, such as the age from the edge, type of matrix and proximity of gaps, may play a more important role in plant community structure than the proximity from edges.

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