Changes in understory composition following catastrophic windthrow and salvage logging in a subalpine forest ecosystem

Catastrophic windthrow and postdisturbance salvage logging each have the potential to profoundly influence understory vegetation communities. This study compared understory vegetation cover, composition, and diversity in Routt National Forest, a subalpine forest in northwestern Colorado that sustained a 10 000 ha blowdown in 1997 and was partially salvage logged in 1999. Understory and edaphic variables were measured in five heavily wind-disturbed Picea–Abies stands, five stands salvage logged 20 months after the blowdown, and five intact stands. Understory species cover and diversity were greater in blown down areas than in salvage-logged or control areas. Community composition of each treatment area was distinct and related to a gradient in organic soil depth, which reflected the severity of understory disturbance. Composition and diversity in blowdown areas relative to control areas stabilized in the 5 years following the blowdown, but vegetation cover continued to increase. Blowdown areas contained early and late successional species. Salvage-logged areas exhibited a shift towards graminoid dominance. This structural change could delay future conifer seedling establishment. The interaction among disturbance severity, understory vegetation composition, and regeneration dynamics should be considered in future decisions to salvage log similar areas because the long-term effects of salvage logging are unknown.

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Understory Vegetation Cover Components Assessment in Anthropogenically Disturbed Birch Stands of Krasnoyarsk Forest-Steppe

Lesnoy Zhurnal (Forestry Journal) ◽

10.37482/0536-1036-2020-1-75-87 ◽

2020 ◽

pp. 75-87

Author(s):

I.A. Goncharova ◽

◽

L.N. Skripal’shchikova ◽

A.P. Barchenkov ◽

A.S. Shushpanov ◽

...

Keyword(s):

Vegetation Cover ◽

Understory Vegetation ◽

Forest Steppe ◽

Understory Vegetation Cover

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Vegetation Cover and Tumuli’s Shape as Affecting Factors of Microclimate and Biodeterioration Risk for the Conservation of Etruscan Tombs (Tarquinia, Italy)

Sustainability ◽

10.3390/su13063393 ◽

2021 ◽

Vol 13 (6) ◽

pp. 3393

Author(s):

Giulia Caneva ◽

Simone Langone ◽

Flavia Bartoli ◽

Adele Cecchini ◽

Carlo Meneghini

Keyword(s):

Vegetation Cover ◽

Cynodon Dactylon ◽

Soil Depth ◽

Late Summer ◽

Positive Influence ◽

Wild Plants ◽

Affecting Factors ◽

Ephemeral Plants ◽

Relevant Role ◽

Hot Season

The conservation of underground tombs is affected by several physical-chemical and biological factors, which could be reduced by insulating systems able to maintain the microclimatic stability also decreasing the biodeterioration risk. In Mediterranean areas, wild ephemeral plants, which reduce their cover during the hot season, seem unsuitable for reducing summer overheating. In this study, we wish to assess the influence of vegetation cover and of overlaying soil, after the establishment of an evergreen turf of a cultivar of Cynodon dactylon, on two tombs in the Etruscan Necropolis of Monterozzi, covered by linear-shaped tumuli. Therefore, we evaluated for 10 months the thermo-hygrometric values of these tombs, together with two tombs as controls. We also evaluated the different tumuli’s morphologies and the related received solar radiation. Results confirmed that late summer and early autumn as critical microclimatic periods for the risk factors of hypogeal paintings when peaks of superficial temperature occur. A positive influence of vegetation cover on maintaining constant humidity and internal temperatures was detected, but the mounds orientation, as well as soil depth, seems to have a relevant role. Considering the naturalistic features of the area and the related cultural ecosystem services, a careful selection of wild plants is suggested.

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Long-term effects of fire on the composition and activity of the soil microflora of a subalpine, coniferous forest

Canadian Journal of Botany ◽

10.1139/b80-199 ◽

1980 ◽

Vol 58 (15) ◽

pp. 1704-1721 ◽

Cited By ~ 60

Author(s):

J. Bissett ◽

D. Parkinson

Keyword(s):

Microbial Biomass ◽

Bacterial Flora ◽

Mineral Soil ◽

Coniferous Forest ◽

Soil Microflora ◽

Subalpine Forest ◽

Long Term Effects ◽

Soil Horizons ◽

Cellulose Decomposition ◽

Soil Temperatures

The biomass, community composition, and metabolic activity of soil microorganisms were studied in adjacent burnt and unburnt areas of spruce–fir subalpine forest razed 6 years previously by a moderately severe natural fire. Similar levels of microbial biomass were observed at comparable burnt and unburnt sites, although the ratio of fungal to bacterial biomass was higher in the unburnt soils. The decreased acidity of the surface horizons in the burn probably tended to favor the development of a bacterial flora rather than a fungal flora. Microbial biomass in the burnt sites peaked earlier in the season than in the unburnt sites in response to the warmer soil temperatures and earlier thaw in the spring in the burn area.Significant differences in the species composition of the mycoflora in the organic soil horizons were observed between the burnt and unburnt sites. Apparently, these were related to qualitative differences in the recent litter. Phoma, Cladosporium, and Botrytis, which are usually associated with early stages of decomposition of herbaceous litter, were more common in the burnt soil. The mycoflora of the mineral soil horizons varied considerably from one burn site to another, possibly reflecting the geographical variation in the intensity of the burn. In overall composition, however, the mycoflora in the mineral soil horizons of the burn was not appreciably different from that of the unburnt sites.Higher laboratory rates of respiration and cellulose decomposition were observed for soil samples from the undisturbed forest. However, the rate of decomposition of cellulose in the field was much higher in the burnt sites, probably as a result of the higher soil temperatures in the burn area. Low soil temperature was concluded to be the main factor limiting microbial activities in the study area, and the removal of the insulating plant canopy and increased heat absorption by the ash in the burn area were found to increase decomposition rates, at least at this stage in the succession following the disturbance of fire.

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Monitoring Winter Stress Vulnerability of High-Latitude Understory Vegetation Using Intraspecific Trait Variability and Remote Sensing Approaches

Sensors ◽

10.3390/s20072102 ◽

2020 ◽

Vol 20 (7) ◽

pp. 2102

Author(s):

Elmar Ritz ◽

Jarle W. Bjerke ◽

Hans Tømmervik

Keyword(s):

Remote Sensing ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Plant Traits ◽

Soil Depth ◽

Plant Stress ◽

Understory Vegetation ◽

Stress Vulnerability ◽

Multi Method Approach ◽

Common Plant

In this study, we focused on three species that have proven to be vulnerable to winter stress: Empetrum nigrum, Vaccinium vitis-idaea and Hylocomium splendens. Our objective was to determine plant traits suitable for monitoring plant stress as well as trait shifts during spring. To this end, we used a combination of active and passive handheld normalized difference vegetation index (NDVI) sensors, RGB indices derived from ordinary cameras, an optical chlorophyll and flavonol sensor (Dualex), and common plant traits that are sensitive to winter stress, i.e. height, specific leaf area (SLA). Our results indicate that NDVI is a good predictor for plant stress, as it correlates well with height (r = 0.70, p < 0.001) and chlorophyll content (r = 0.63, p < 0.001). NDVI is also related to soil depth (r = 0.45, p < 0.001) as well as to plant stress levels based on observations in the field (r = −0.60, p < 0.001). Flavonol content and SLA remained relatively stable during spring. Our results confirm a multi-method approach using NDVI data from the Sentinel-2 satellite and active near-remote sensing devices to determine the contribution of understory vegetation to the total ecosystem greenness. We identified low soil depth to be the major stressor for understory vegetation in the studied plots. The RGB indices were good proxies to detect plant stress (e.g. Channel G%: r = −0.77, p < 0.001) and showed high correlation with NDVI (r = 0.75, p < 0.001). Ordinary cameras and modified cameras with the infrared filter removed were found to perform equally well.

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Viable seed populations by soil depth and potential site recolonization after disturbance

Canadian Journal of Botany ◽

10.1139/b77-274 ◽

1977 ◽

Vol 55 (18) ◽

pp. 2408-2412 ◽

Cited By ~ 88

Author(s):

Janice M. Moore ◽

Ross W. Wein

Keyword(s):

Soil Depth ◽

Seedling Emergence ◽

Mineral Soil ◽

Organic Soil ◽

Viable Seed ◽

Soil Layers ◽

Forest Experiment Station ◽

Viable Seeds ◽

Study Sites ◽

Germination Experiment

Seedling emergence from organic and mineral soil layers was measured for nine study sites at the Acadia Forest Experiment Station near Fredericton, New Brunswick. The number of viable seeds showed a decrease from deciduous-dominated forest, to conifer-dominated forest, to organic soil study sites. Viable seed number varied from 3400/m2 for a deciduous-dominated forest study site to zero for a bog study site. Most seeds germinated from the upper organic soil layers of all study sites and were predominantly Rubus strigosus Michx. After the germination experiment, ungerminated seeds, which showed no viability by the tetrazolium test, were separated from the soil. These seeds were almost entirely Betula spp. and seed numbers were as high as 4200–9400/m2 for a deciduous-dominated forest. The applicability of the results to differing types of postdisturbance revegetation is discussed.

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Influence of conservation tillage practices on soil properties and crop yields for maize and wheat cultivation in Beijing, China

Soil Research ◽

10.1071/sr08110 ◽

2009 ◽

Vol 47 (4) ◽

pp. 362 ◽

Cited By ~ 18

Author(s):

Xirui Zhang ◽

Hongwen Li ◽

Jin He ◽

Qingjie Wang ◽

Mohammad H. Golabi

Keyword(s):

Soil Properties ◽

Crop Yields ◽

Conservation Tillage ◽

Soil Depth ◽

Chemical Properties ◽

Conventional Tillage ◽

Production Costs ◽

Long Term Effects ◽

Available N ◽

Beijing Area

Conservation tillage is becoming increasingly attractive to farmers because it involves lower production costs than does conventional tillage. The long-term effects of sub-soiling tillage (ST), no tillage (NT), and conventional tillage (CT) on soil properties and crop yields were investigated over an 8-year period (2000–07). The study was conducted in a 2-crop-a-year region (Daxing) and a 1-crop-a-year region (Changping) of the Beijing area in China. At 0–0.30 m soil depth, water stability of macro-aggregates (>0.25 mm) was much greater for ST (22.1%) and NT (12.0%) than for CT in Daxing, and the improvements in Changping were 18.9% and 9.5%, respectively. ST and NT significantly (P < 0.05) improved aeration porosity by 14.5% and 10.6%, respectively, at Daxing and by 17.0% and 8.6% at Changping compared with CT treatment. Soil bulk density after 8 years was 0.8–1.5% lower in ST and NT treatments than in CT at both sites. Soil organic matter and available N and P followed the same order ST ≈ NT > CT at both sites. Consequently, crop yields in ST and NT plots were higher than in CT plots due to improved soil physical and chemical properties. Within the conservation tillage treatments, despite similar economic benefit, the effects on crop yields for ST were better than for NT. Mean (2000–07) crop yields for ST were 0.2% and 1.5% higher than for NT at Daxing and Changping, respectively. We therefore conclude that ST is the most suitable conservation tillage practice for annual 2-crop-a-year and 1-crop-a-year regions in the Beijing area.

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Profile in various organic soil depth shrimp pond, Tambak Inti Rakyat, Karawang

Jurnal Akuakultur Indonesia ◽

10.19027/jai.10.183-191 ◽

2015 ◽

Vol 10 (2) ◽

pp. 183

Author(s):

Yuni Puji Hastuti ◽

Lena Novita ◽

Tri Widiyanto ◽

Iman Rusmana

Keyword(s):

Organic Material ◽

Soil Depth ◽

Bottom Layer ◽

Organic Soil ◽

Organic N ◽

Intensive Culture ◽

Culture Systems ◽

Mangrove Area ◽

Control Sediment ◽

Different Depths

ABSTRACT Organic material in the bottom of the pond is part of the land is a complex and dynamic system, which is sourced from the rest of the feed, plants, and or animals found in the soil that continuously change shape, because it is influenced by biology, physics, and chemistry. This study was aimed to see the profile of organic material consisting of C, N, and C/N ratio and phosphate in different depths of pond with different culture systems. Observation were conducted at Tambak Inti Rakyat, Karawang in traditional, semi-intensive and intensive culture systems. Observation at mangrove area was also observed as control. Sediment samples at the inlet and outlet at three different depths (0‒5 cm, 5‒10 cm, and 10‒15 cm) was taken every 30 days to measure the content of C, N, C/N ratio, and total phosphate. During the 120 day maintenance period could be known that in all pond systems were used (traditional, semi-intensive, and intensive) the concentration of C-organic and organic-N on average was located in the bottom layer which is a layer of 10‒15 cm. The lack of human intervention from ground pond system, the more diverse the type and amount of organic material contained therein. Keywords: organic materials, subgrade, depth, aquaculture systems, long maintenance ABSTRAK Bahan organik di dasar tambak merupakan bagian dari tanah yang merupakan suatu sistem kompleks dan dinamis, yang bersumber dari sisa pakan, tanaman, dan atau binatang yang terdapat di dalam tanah yang terus menerus mengalami perubahan bentuk, karena dipengaruhi oleh faktor biologi, fisika, dan kimia. Penelitian ini bertujuan untuk melihat profil bahan organik yang terdiri dari C, N, dan C/N rasio serta fosfat pada kedalaman tambak yang berbeda dengan sistem budidaya yang berbeda pula. Pengamatan dilakukan di Tambak Inti Rakyat Karawang pada sistem budidaya tradisional, semi intensif, dan intensif. Pengamatan di daerah mangrove diamati pula sebagai kontrol. Sampel sedimen di inlet dan outlet pada tiga kedalaman yang berbeda (0‒5 cm, 5‒10 cm, dan 10‒15 cm) diambil setiap 30 hari sekali untuk diukur kandungan C, N, C/N rasio, dan total fosfatnya. Selama 120 hari masa pemeliharaan dapat diketahui bahwa pada semua sistem tambak yang digunakan (tradisional, semi intensif, dan intensif) nilai konsentrasi C-organik dan N-organik rata-rata terletak pada lapisan paling bawah yaitu lapisan 10‒15 cm. Minimnya campur tangan manusia dari tanah sistem tambak maka semakin beragam jenis dan jumlah dari bahan organik yang terkandung di dalamnya. Kata kunci: bahan organik, tanah dasar, kedalaman, sistem budidaya, lama pemeliharaan

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Post-fire vegetation succession in the Siberian subarctic tundra over 45 years

10.1101/756163 ◽

2019 ◽

Author(s):

Ramona J. Heim ◽

Anna Bucharova ◽

Leya Brodt ◽

Johannes Kamp ◽

Daniel Rieker ◽

...

Keyword(s):

Soil Temperature ◽

Vegetation Cover ◽

The Arctic ◽

Vegetation Recovery ◽

Long Term Effects ◽

Forest Tundra ◽

Permafrost Thaw ◽

Legacy Effect ◽

Thaw Depth

AbstractWildfires are relatively rare in subarctic tundra ecosystems, but they can strongly change ecosystem properties. Short-term fire effects on subarctic tundra vegetation are well documented, but long-term vegetation recovery has been studied less. The frequency of tundra fires will increase with climate warming. Understanding the long-term effects of fire is necessary to predict future ecosystem changes.We used a space-for-time approach to assess vegetation recovery after fire over more than four decades. We studied soil and vegetation patterns on three large fire scars (>44, 28 and 12 years old) in dry, lichen-dominated forest tundra in Western Siberia. On 60 plots, we determined soil temperature and permafrost thaw depth, sampled vegetation and measured plant functional traits. We assessed trends in NDVI to support the field-based results on vegetation recovery.Soil temperature, permafrost thaw depth and total vegetation cover had recovered to pre-fire levels after >44 years, as well as total vegetation cover. In contrast, after >44 years, functional groups had not recovered to the pre-fire state. Burnt areas had lower lichen and higher bryophyte and shrub cover. The dominating shrub species, Betula nana, exhibited a higher vitality (higher specific leaf area and plant height) on burnt compared with control plots, suggesting a fire legacy effect in shrub growth. Our results confirm patterns of shrub encroachment after fire that were detected before in other parts of the Arctic and Subarctic. In the so far poorly studied Western Siberian forest tundra we demonstrate for the first time, long-term fire-legacies on the functional composition of relatively dry shrub- and lichen-dominated vegetation.

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Short and long-term effects of fire and vegetation cover on four lizard species in Amazonian savannas

Canadian Journal of Zoology ◽

10.1139/cjz-2020-0224 ◽

2020 ◽

Author(s):

Erika dos Santos Souza ◽

Albertina P. Lima ◽

William E. Magnusson ◽

RICARDO ALEXANDRE KAWASHITA-RIBEIRO ◽

Rodrigo Ferreira Fadini ◽

...

Keyword(s):

Vegetation Cover ◽

Long Term Effects ◽

Short Term ◽

Lizard Species ◽

Random Factor ◽

Positive Effects ◽

Temporal Sampling ◽

Short And Long Term ◽

Main Effects

Ecological succession in tropical savannas is limited by seasonal fire, which affects habitat quality. Although fire may cause negligible or positive effects on animals occupying savannas, most short-term studies (months to a few years) are based on a single temporal sampling snapshot, and long-term studies (decades) are rare. We sampled four lizard species in Amazonian savannas to test the effects of fire and vegetation cover on lizard densities at two temporal scales. In the short-term, we use three sampling snapshots to test the effects of fire and vegetation cover on estimated lizard densities over the subsequent 1–5 years. In the long-term, we test the effects of fire and changes in vegetation cover over 21 years on current lizard density differences. In the short-term, species responses were usually consistent with foraging and thermoregulation modes. However, the results were not consistent among species and years, although the variances in species density explained by year as a random factor were generally low. In the long-term, the main effects of fire and vegetation cover show that lizard densities may change spatially, but not necessarily temporarily. Wildfire is a natural resource of savannas and apparently have little impact on resident lizards of that ecosystem.

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