Effect of bench terracing on ground dwelling arthropods

Eucalypt trees are the most planted tree in the world, and in Portugal these plantations occupy 26% of the forested area. The area of Eucalypt monoculture is growing since the 50&#8217;s due to the importance of this tree for the pulp and paste industry. With short rotation cycles, it is important to facilitate the cut and transport of the logged trees. In this sense, many forested areas in mountainous regions are being terraced with bulldozers.Terracing is a well know soil conservation practice, reducing runoff peak flows, increasing water infiltration and subsequent low soil erosion rates. Nevertheless, the impacts of terracing for eucalypt plantations are still unknown, especially in terms of biodiversity of soil fauna. Hence, to address this research gap, the present study aimed to assess the impacts of terracing on the ground dwelling arthropods in eucalypt plantations.This study took place in a mountain slope with old eucalypt trees that were logged (May 2019) and then terraced (July) as ground preparation to receive a new eucalypt plantation. The community of ground dwelling arthropods were accessed using pitfall traps. &#160;The arthropods were collected before the terracing process, in Spring 2019, and then seasonally after terracing until the Spring of 2020Total abundance and richness at order level, as well as, abundance, richness, Shannon-Wiener diversity and Pielou&#8217;s Evenness indexes, at Family level of Coleoptera, Araneae and Hymenoptera, were used to depict differences between pre- and post-terracing. The results showed that although terracing did not reduce the total abundance or richness, it changed the community structure. In particular, it was observed an increase in opportunist and generalist families after terracing such as Staphylinidae and Myrmicinae. The spider community also changed, with more hunter families captured after the terrace construction. In overall, the results of our study reveal that although the total abundance and richness of arthropods was not altered by the construction of terraces, their structure was modified.

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Changing the face of short fiber –a review of the eucalyptus revolution

TAPPI Journal ◽

10.32964/tj14.6.353 ◽

2015 ◽

Vol 14 (6) ◽

pp. 353-359 ◽

Cited By ~ 6

Author(s):

PETER W. HART ◽

RICARDO B. SANTOS

Keyword(s):

Fossil Fuels ◽

Wood Quality ◽

Short Fiber ◽

Fiber Volume ◽

Private Industry ◽

High Productivity ◽

Paper Manufacturing ◽

Short Rotation ◽

Eucalypt Plantations ◽

Eucalyptus Plantations

Eucalyptus plantations have been used as a source of short fiber for papermaking for more than 40 years. The development in genetic improvement and clonal programs has produced improved density plantations that have resulted in fast growing, increased fiber volume eucalypts becoming the most widely used source of short fibers in the world. High productivity and short rotation times, along with the uniformity and improved wood quality of clonal plantations have attracted private industry investment in eucalypt plantations. Currently, only a handful of species or hybrids are used in plantation efforts. Many more species are being evaluated to either enhance fiber properties or expand the range of eucalypt plantations. Eucalyptus plantations are frequently planted on nonforested land and may be used, in part, as a means of conserving native forests while allowing the production of high quality fiber for economic uses. Finally, eucalypt plantations can provide significant carbon sinks, which may be used to help offset the carbon released from burning fossil fuels. The development and expansion of eucalypt plantations represents a substantial revolution in pulp and paper manufacturing.

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Three-year dynamics of N2O fluxes from soil, stem and canopy in a hemiboreal forest: Impacts of floods and droughts

10.5194/egusphere-egu2020-7760 ◽

2020 ◽

Author(s):

Ülo Mander ◽

Thomas Schindler ◽

Kateřina Macháčová ◽

Alisa Krasnova ◽

Jordi Escuer-Gatius ◽

...

Keyword(s):

Agricultural Land ◽

Soil Surface ◽

Alnus Incana ◽

Carbon Dioxide Fluxes ◽

Short Rotation ◽

Long Term Study ◽

Forested Areas ◽

Ecosystem Level ◽

Intact Soil Cores

Forests are important regulators of carbon dioxide fluxes, whereas overall greenhouse gas (GHG) budgets, in particular, nitrous oxide (N2O), are still largely unknown. No studies on ecosystem-level N2O budgets (soil and tree stem fluxes with eddy covariance (EC) measurements above the canopy) are found. Only a few examples are available on N2O emissions from tree stems. Nevertheless, estimation of the N2O and the full GHG balance in different forest ecosystems under various environmental conditions is essential to understand their impact on climate.During the period of August 2017 to December 2019, we measured the N2O budget of a 40-yr old hemiboreal grey alder (Alnus incana) forest stand on former agricultural land in Estonia considering fluxes from the soil, tree stems and whole ecosystem. Grey alder (Alnus incana) is a fast-growing tree species typically found in riparian zones, with great potential for short-rotation forestry. Their symbiotic dinitrogen (N2) fixation ability makes alders important for the regulation of nitrogen (N) cycle in forested areas.We measured the N2O budget considering fluxes from the soil surface (12 automated chambers; Picarro 2508), tree stems (60 manual sampling campaigns from 12 model trees with chambers at 0.1, 0.8 and 1.7 m; gas chromatographic analysis in lab) and whole ecosystem (EC technique: Aerodyne TILDAS). Simultaneously, soil water level, temperature and moisture were measured automatically, and composite soil samples were taken for physico-chemical analysis. Potential N2 flux in intact soil cores was measured in the lab using the He-O incubation method.Average N2O fluxes from the soil and tree stems varied from 1.2 to 3.0 and 0.01 to 0.03 kg N2O-N ha&#8211;1 yr&#8211;1, respectively, being the highest during the wet periods, peaking during the freezing-thawing, and being the lowest in dry periods. The average annual potential N2 flux in the soil was 140 kg N2 ha&#8211;1 yr&#8211;1 which made the average N2:N2O-N ratio in the soil about 60. According to the EC measurements, the forest was a net annual source of N2O (3.4 kg N2O ha&#8211;1). Thus, the main gaseous nitrogen flux in this forest was N2 emission. Our carbon (C) budget showed that the forest was a significant net annual C sink.Results of our long-term study underline the high N and C buffering capacity of riparian alder forests. For better understanding of C and nutrient budgets of riparian forests, we need long-term, high-frequency measurements of N2O fluxes from the soil and tree stems in combination with ecosystem-level EC measurements. The identification of microorganisms and biogeochemical pathways associated with N2O production and consumption is another future challenge.

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Effects of oil palm plantations on anuran diversity in the eastern Amazon

Animal Biology ◽

10.1163/15707563-00002481 ◽

2015 ◽

Vol 65 (3-4) ◽

pp. 321-335 ◽

Cited By ~ 14

Author(s):

Fabricio S. Correa ◽

Leandro Juen ◽

Lenise C. Rodrigues ◽

Heriberto F. Silva-Filho ◽

Maria C. Santos-Costa

Keyword(s):

Land Use ◽

Species Richness ◽

Oil Palm ◽

Soil Conditions ◽

Total Abundance ◽

Anuran Species ◽

Forested Areas ◽

Acoustic Surveys ◽

Negative Impacts ◽

The Tropics

The extent of land use for oil palm plantations has grown considerably in the tropics due to climate, appropriate soil conditions for cultivation and its profitability. However, oil palm plantations may endanger biodiversity through reduction and fragmentation of forest areas. Herein we analyzed the effects on anuran species richness, composition and total abundance in oil palm plantations and surrounding forests in eastern Amazon. We installed seven plots in oil palm plantations and seven plots in surrounding forests, which we surveyed for the presence of anurans through active visual and acoustic surveys during periods of high and low rainfall levels. Anuran assemblages found in forests and oil palm plantations differed in species richness and composition, with a loss of 54% of species in oil palm plantations. No difference was observed in total abundance of anurans between both environments. While conversion of forests to oil palm plantations may result in less negative impacts on anuran diversity than other types of monocultures, such loss is nevertheless high, making the maintenance of relatively greater forested areas around oil palm plantations necessary in order to conserve anuran diversity.

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Soils and earthworms as a final chapter in the narrative of a steelworks

10.37208/tgn27208 ◽

2020 ◽

Vol 27 (2) ◽

pp. 39-48

Author(s):

K.R Butt ◽

S.M Quigg

Keyword(s):

Sewage Sludge ◽

Vegetation Cover ◽

Water Infiltration ◽

Ecological Groups ◽

Short Rotation ◽

Density And Biomass ◽

Reclaimed Soils ◽

Planted Tree ◽

Salix Spp

Hallside steelworks, South Lanarkshire, Scotland, employed thousands of people and constructed rails and ships for over a century, before this successful industry closed in the 1970s. The site,south-east of Glasgow, was then reclaimed from dereliction during the 1990s to produce biomass through Short Rotation Coppice (SRC) of willow trees (Salix spp.). On site, the contaminated soil was removed, and a rudimentary substrate created with a mixture of sewage sludge and colliery spoil, the latter moved from nearby tips to release land for housing. Trees were planted and earthworms (Annelida) added to potentially assist growth. Initially recognised as a flagship for reclamation, the site was then abandoned. In 2018, information was gathered on the development of soils and on earthworm communities. This was achieved by sampling across the 35 ha site below willow, other planted tree species and grassland. The results showed that reclaimed soils were very stony, compacted, resistant to water infiltration but relatively uncontaminated. Willow had grown, but coppicing had not occurred. Earthworm introduction was initially unsuccessful, but colonisation took place from adjacent unadulterated areas and 16 species from three ecological groups were recorded. Mean community density was 208 ± 18.1 earthworms m-2 with a mean mass of 71 ± 6.1 g m-2. Type of vegetation cover had a significant (P <0.05) effect on community density and biomass. The site is now used for recreation and is an effective greenspace close to Glasgow.

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MECHANISED HARVEST OF ENERGY WOOD: STATE-OF-THE-ART AND NEW DEVELOPMENTS

Revista Engenharia na Agricultura - REVENG ◽

10.13083/reveng.v24i1.638 ◽

2016 ◽

Vol 24 (1) ◽

pp. 32-40

Author(s):

Ralf Pecenka ◽

Jadir Nogueira Silva ◽

Detlef Ehlert ◽

Gerd Volkhard Scholz

Keyword(s):

Field Performance ◽

Stem Diameter ◽

Fast Growing ◽

Mountainous Regions ◽

Energy Wood ◽

Short Rotation ◽

Low Weight ◽

Production Technologies ◽

And Performance ◽

Forage Harvester

Energy wood from fast growing trees, also called short rotation coppice (SRC) such as poplar, willow and eucalyptus, may provide a secure source of income for farmers, provided that production technologies, logistic chains and end user facilities are well designed in farmers’ regional structures. One of the key problems at present is the lack of inexpensive harvesting machinery. Analyzing the process chain of fast growing trees, chip lines seem to be most costefficient for harvest, and the modification of forage harvesters is a promising option. But the high machine weight of forage harvesters is a serious disadvantage for harvest in rain-laden or mountainous regions. Furthermore, for economic operation of these expensive harvest systems cultivation areas of more than 300 ha are required. Therefore, a simple and low weight tractor-mounted mower-chipper for medium sized standard tractors has been developed. The chipper is designed for flexible harvest of wood from fast growing trees (max. stem diameter 15 cm). The total weight of the harvester (tractor and chipper) is less than 50 % of the forage harvester combination resulting in much more flexible field operation and lower harvest costs. The machine has been successfully tested in the last three harvest seasons on an area of more than 110 ha. At harvest of 4 years old poplars (10 - 15 cm stem diameter) an average field performance of 0.5 ha h-1 has been realized. Due to the robust design and performance of the prototype the development of a reinforced model is considered at present. Such a new model could be designed for harvest of poplar or eucalyptus trees with stem diameters of more than 20 cm.

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Detailed reconstruction of gully headcut retreat using exposed tree roots: a case study from the Vsetínské vrchy Mts. (Outer Western Carpathians)

Geografie ◽

10.37040/geografie2018123020179 ◽

2018 ◽

Vol 123 (2) ◽

pp. 179-199

Author(s):

Karel Šilhán

Keyword(s):

Good Alternative ◽

Tree Roots ◽

Erosion Rates ◽

Highly Active ◽

Time Period ◽

Outer Western Carpathians ◽

Forested Areas ◽

Root Exposure ◽

Active Channels ◽

Headcut Retreat

Gully erosion is a widespread natural hazard that causes substantial financial losses every year. Dendrogeomorphic (tree ring-based) methods are a good alternative approach for assessing gully development in forested areas. The majority of previous dendrogeomorphic studies dealing with erosion focused on sheet erosion or erosion rates in the active channels of old, stabilized gullies. This study aims to asses newly originated gully development based on an analysis of exposed tree roots. Moreover, the root exposure data were used to calculate rates of linear and areal gully headcut retreat (GHR). In total, 81 samples (microcuts) from common spruce (Picea abies (L.) Karst) were analyzed for anatomical responses to root exposure. The existence of the shallow channel preceding the gully itself was identified. This GHR reconstruction (for a limited time period of eight years) provides evidence of highly active gully development in the forested area of the Flysch Carpathians that is comparable with results from semi-arid regions.

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Characteristics, distribution and susceptibility of natural and human-induced landslides in a tropical mountainous region: the Rift flank west of Lake Kivu (DR Congo)

10.5194/egusphere-egu21-13380 ◽

2021 ◽

Author(s):

Jean-Claude Maki Mateso ◽

Charles Bielders ◽

Elise Monsieurs ◽

Arthur Depicker ◽

Benoît Smets ◽

...

Keyword(s):

Management Practices ◽

Google Earth ◽

Shallow Landslides ◽

Water Infiltration ◽

Aerial Photographs ◽

Anthropogenic Factors ◽

Natural Environments ◽

Dr Congo ◽

Mountainous Regions ◽

Lake Kivu

Tropical mountainous regions are often identified as landslide hotspots with particularly vulnerable populations. Whereas both natural (e.g., rainfall, lithology) and anthropogenic (e.g., deforestation, mining) factors are expected to be involved in landslide occurrence, the relative importance of such factors remains poorly documented. The objective of this study is to understand the role played by natural and anthropogenic factors in the occurrence of landslides in the Rift Flank west of Lake Kivu in DR Congo. First, we inventoried 2856 landslides of various types using Google Earth imagery, high resolution topographic data, historical aerial photographs from1950&#8217;sand intense field surveys. We made a distinction between old and recent deep-seated landslides, shallow landslides and mining-related landslides. The difference in susceptibility patterns and in size distributions between old and recent deep-seated landslides indicates that natural factors contributing to their occurrence were either different or changed over time. The shallow landslides are all recent. The susceptibility analysis shows that their regional pattern is mainly controlled by forest dynamics and the presence of roads. The occurrence of shallow landslides in forest areas, i.e. in natural environments, strongly increases with slope gradient. In areas with similar topographic conditions where deforestation has occurred since the 1950&#8217;s, shallow landslides are more frequent, but of smaller size. This size reduction is attributed to the decrease of regolith cohesion due to forest loss, which allows a smaller minimum critical area for landsliding. In areas that were already deforested in 1950&#8217;s, shallow landslides are less frequent, larger, and occur on less steep slopes. This suggests a combined role between regolith availability and soil management practices that influence erosion and water infiltration. Landslides associated with mining activities are larger than shallow landslides but smaller than the recent deep-seated instabilities. They are not well predicted by the susceptibility models, showing that they respond to environmental factors that are not present under natural conditions. This research highlights the importance of human activities on the occurrence of landslides and the need to consider this context when studying hillslope instability patterns in regions under anthropic pressure.&#160;Keywords: landslide processes, multi-temporal inventory, historical deforestation, mining and quarrying, susceptibility assessment, Africa

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Autonomous Aerial Vehicles (AAVs) as a Tool for Improving the Spatial Resolution of Snow Albedo Measurements in Mountainous Regions

Hydrology ◽

10.3390/hydrology7030041 ◽

2020 ◽

Vol 7 (3) ◽

pp. 41

Author(s):

Eric A. Sproles ◽

Andrew Mullen ◽

Jordy Hendrikx ◽

Charles Gatebe ◽

Suzi Taylor

Keyword(s):

Spatial Resolution ◽

Spatial Scales ◽

Satellite Measurements ◽

Snow Albedo ◽

Mountainous Regions ◽

Clear Sky ◽

Dual Sensor ◽

Forested Areas ◽

Technical Advances ◽

Aerial Vehicle

We present technical advances and methods to measure effective broadband physical albedo in snowy mountain headwaters using a prototype dual-sensor pyranometer mounted on an Autonomous Aerial Vehicle (an AAV). Our test flights over snowy meadows and forested areas performed well during both clear sky and snowy/windy conditions at an elevation of ~2650 m above mean sea level (MSL). Our AAV-pyranometer platform provided high spatial (m) and temporal resolution (sec) measurements of effective broadband (310–2700 nm) surface albedo. The AAV-based measurements reveal spatially explicit changes in landscape albedo that are not present in concurrent satellite measurements from Landsat and MODIS due to a higher spatial resolution. This AAV capability is needed for validation of satellite snow albedo products, especially over variable montane landscapes at spatial scales of critical importance to hydrological applications. Effectively measuring albedo is important, as annually the seasonal accumulation and melt of mountain snowpack represent a dramatic transformation of Earth’s albedo, which directly affects headwaters’ water and energy cycles.

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Structure from Motion of Multi-Angle RPAS Imagery Complements Larger-Scale Airborne Lidar Data for Cost-Effective Snow Monitoring in Mountain Forests

Remote Sensing ◽

10.3390/rs12142311 ◽

2020 ◽

Vol 12 (14) ◽

pp. 2311

Author(s):

Patrick D. Broxton ◽

Willem J. D. van Leeuwen

Keyword(s):

Structure From Motion ◽

Snow Depth ◽

Cost Effective ◽

Airborne Lidar ◽

Mountain Forests ◽

Mountainous Regions ◽

Basin Scale ◽

Remotely Piloted Aircraft ◽

Multi Temporal ◽

Forested Areas

Snowmelt from mountain forests is critically important for water resources and hydropower generation. More than 75% of surface water supply originates as snowmelt in mountainous regions, such as the western U.S. Remote sensing has the potential to measure snowpack in these areas accurately. In this research, we combine light detection and ranging (lidar) from crewed aircraft (currently, the most reliable way of measuring snow depth in mountain forests) and structure from motion (SfM) remotely piloted aircraft systems (RPAS) for cost-effective multi-temporal monitoring of snowpack in mountain forests. In sparsely forested areas, both technologies give similar snow depth maps, with a comparable agreement with ground-based snow depth observations (RMSE ~10 cm). In densely forested areas, airborne lidar is better able to represent snow depth than RPAS-SfM (RMSE ~10 cm vs ~10–20 cm). In addition, we find the relationship between RPAS-SfM and previous lidar snow depth data can be used to estimate snow depth conditions outside of relatively small RPAS-SfM monitoring plots, with RMSE’s between these observed and estimated snow depths on the order of 10–15 cm for the larger lidar coverages. This suggests that when a single airborne lidar snow survey exists, RPAS-SfM may provide useful multi-temporal snow monitoring that can estimate basin-scale snowpack, at a much lower cost than multiple airborne lidar surveys. Doing so requires a pre-existing mid-winter or peak-snowpack airborne lidar snow survey, and subsequent well-designed paired SfM and field snow surveys that accurately capture substantial snow depth variability.

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SPIDER DIVERSITY (ARACHNIDA: ARANEAE) OF THE TEA PLANTATION AT SERANG VILLAGE, KARANGREJA SUB-DISTRICT, DISTRICT OF PURBALINGGA

Scripta Biologica ◽

10.20884/1.sb.2017.4.2.402 ◽

2017 ◽

Vol 4 (2) ◽

pp. 95

Author(s):

Gianti Sibarani ◽

Imam Widhiono ◽

Darsono Darsono

Keyword(s):

Insect Pest ◽

Cropping System ◽

Sampling Techniques ◽

Total Abundance ◽

Pesticide Application ◽

Pest Population ◽

Tea Plantation ◽

Spider Community ◽

Spider Abundance ◽

Abundance And Diversity

Spiders are crucial in controlling insect pest population. The various cultivation managements such as fertilizer and pesticide application, weeding, pruning, harvesting, and cropping system affect their diversity. In the plantation, vegetation diversification has applied various practices, including monoculture, and intercropping, which influence the spider community. Thus, this study was intended to determine the spider abundance and diversity of the tea plantation, and the intercropping field (tea and strawberry) at Serang village, Karangreja Sub-District, District of Purbalingga. A survey and purposive sampling techniques were conducted, then the spiders were hand collected. Shannon-Wiener diversity (H’), Evenness (E), Simpson’s dominance (D), and Sorensen’s similarity (IS) indices were used to measure the spider diversity. The results revealed a total number of 575 individual spiders from 10 families, i.e., Araneae, Araneidae, Clubionidae, Linyphiidae, Lycosidae, Nephilidae, Oxyopidae, Salticidae, Tetragnathidae, Theridiidae, and Thomisidae. Araneidae was the most abundant in both fields. The total abundance of spiders in tea plantation (379 individuals), however, was greater than that in the intercropping field (196 individuals). Shannon-Wiener diversity reached H’= 1.873 in the plantation, and H’= 1.975 in the intercropping field.

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