Surface Soil Changes Following Selective Logging in an Eastern Amazon Forest

Abstract In the Brazilian Amazon, selective logging is second only to forest conversion in its extent. Conversion to pasture or agriculture tends to reduce soil nutrients and site productivity over time unless fertilizers are added. Logging removes nutrients in bole wood, enough that repeated logging could deplete essential nutrients over time. After a single logging event, nutrient losses are likely to be too small to observe in the large soil nutrient pools, but disturbances associated with logging also alter soil properties. Selective logging, particularly reduced-impact logging, results in consistent patterns of disturbance that may be associated with particular changes in soil properties. Soil bulk density, pH, carbon (C), nitrogen (N), phosphorus (P), calcium (Ca), magnesium (Mg), potassium (K), iron (Fe), aluminum (Al), δ13C, δ15N, and P fractionations were measured on the soils of four different types of logging-related disturbances: roads, decks, skids, and treefall gaps. Litter biomass and percent bare ground were also determined in these areas. To evaluate the importance of fresh foliage inputs from downed tree crowns in treefall gaps, foliar nutrients for mature forest trees were also determined and compared to that of fresh litterfall. The immediate impacts of logging on soil properties and how these might link to the longer-term estimated nutrient losses and the observed changes in soils were studied. In the most disturbed areas, roads and decks, the authors found litter biomass removed and reduced soil C, N, P, particularly organic P, and δ13C. Soils were compacted and often experienced reducing conditions in the deck areas, resulting in higher pH, Ca, and Mg. No increases in soil nutrients were observed in the treefall gaps despite the flush of nutrient-rich fresh foliage in the tree crown that is left behind after the bole wood is removed. Observed nutrient losses are most likely caused by displacement of the litter layer. Increases in soil pH, Ca, and Mg occur in areas with reducing conditions (decks and roads) and may result from Fe reduction, freeing exchange sites that can then retain these cations. Calculations suggest that nutrient inputs from crown foliage in treefall gaps are probably too small to detect against the background level of nutrients in the top soils. The logging disturbances with the greatest spatial extent, skids and gaps, have the smallest immediate effect on soil nutrients, while those with the smallest spatial extent, roads and decks, have the largest impact. The changes observed 3–6 months after logging were similar to those measured 16 yr after logging, suggesting some interesting linkages between the mechanisms causing the immediate change and those maintaining these changes over time. The direct impacts on soil properties appear less important than the loss of nutrients in bole wood in determining the sustainability of selective logging. Medium-to-low intensity selective logging with a sufficiently long cutting cycle may be sustainable in these forests.

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A Comparison of the Attributes of Pine Straw from Southern Pine Species

Journal of Environmental Horticulture ◽

10.24266/0738-2898-39.3.115 ◽

2021 ◽

Vol 39 (3) ◽

pp. 115-122

Author(s):

Zachary Singh ◽

Adam Maggard ◽

Rebecca Barlow ◽

John Kush

Keyword(s):

Soil Moisture ◽

Soil Temperature ◽

Soil Properties ◽

Soil Nutrients ◽

Longleaf Pine ◽

Pinus Palustris ◽

Pinus Elliottii ◽

Slash Pine ◽

Weed Growth ◽

Pine Straw

Abstract Longleaf pine (Pinus palustris Mill.), and slash pine (Pinus elliottii Engelm.) are two southern pine species that are popular for producing pine straw for landscaping. The objective of this research was to determine the response of soil properties and weed growth to the application of pine straw. Longleaf pine, slash pine, and two non-mulched controls (with and without chemical weed control) were tested. Volumetric soil water content, soil nutrients, soil temperature, weed biomass, and seedling growth were measured. Compared to non-mulched controls, both longleaf and slash pine plots had a greater soil moisture during extended periods without rainfall in the full sun environment. When soil temperatures increased, mulched plots had lower soil temperature relative to non-mulched plots. Soil pH and soil nutrients were generally similar between pine straw types with few significant differences in measured variables. Both pine straw treatments reduced weed growth and longleaf pine maintained a greater straw depth over the study period compared to slash pine, but no differences were observed for decomposition. These results indicate that longleaf pine straw and slash pine straw perform equally as well in terms of increasing soil moisture, moderating soil temperature, and reducing weed growth compared to not using mulch. Index words: Pinus elliottii, Pinus palustris, organic mulch, soil properties, landscaping. Species used in this study: Shumard oak, Quercus shumardii Buckl., Eastern redbud, Cercis canadensis L.

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Soil microbial communities in the face of changing farming practices: A case study in an agricultural landscape in France

PLoS ONE ◽

10.1371/journal.pone.0252216 ◽

2021 ◽

Vol 16 (6) ◽

pp. e0252216

Author(s):

Laurie Dunn ◽

Christophe Lang ◽

Nicolas Marilleau ◽

Sébastien Terrat ◽

Luc Biju-Duval ◽

...

Keyword(s):

Microbial Biomass ◽

Soil Properties ◽

Microbial Communities ◽

Soil Microorganisms ◽

Soil Microbial Communities ◽

Partial Least Square ◽

Farming Practices ◽

Soil Microbial ◽

Bacterial Richness ◽

Over Time

According to biogeography studies, the abundance and richness of soil microorganisms vary across multiple spatial scales according to soil properties and farming practices. However, soil microorganisms also exhibit poorly understood temporal variations. This study aimed at better understanding how soil microbial communities respond to changes in farming practices at a landscape scale over time. A regular grid of 269 sites was set up across a 1,200 ha farming landscape, and soil samples were characterized for their molecular microbial biomass and bacterial richness at two dates (2011 and 2016). A mapping approach highlighted that spatial microbial patterns were stable over time, while abundance and richness levels were modified. The drivers of these changes were investigated though a PLS-PM (partial least square path-modeling) approach. Soil properties were stable over time, but farming practices changed. Molecular microbial biomass was mainly driven by soil resources, whereas bacterial richness depended on both farming practices and ecological parameters. Previous-crop and management effects and a temporal dependence of the microbial community on the historical farming management were also highlighted.

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Long-Term Impacts of Selective Logging on Amazon Forest Dynamics from Multi-Temporal Airborne LiDAR

Remote Sensing ◽

10.3390/rs11060709 ◽

2019 ◽

Vol 11 (6) ◽

pp. 709 ◽

Cited By ~ 10

Author(s):

Ekena Rangel Pinagé ◽

Michael Keller ◽

Paul Duffy ◽

Marcos Longo ◽

Maiza dos-Santos ◽

...

Keyword(s):

Laser Scanning ◽

Forest Canopy ◽

Binary Classification ◽

Forest Degradation ◽

Selective Logging ◽

Ecological Impacts ◽

Airborne Lidar ◽

Classification Model ◽

Amazon Forest ◽

Gap Formation

Forest degradation is common in tropical landscapes, but estimates of the extent and duration of degradation impacts are highly uncertain. In particular, selective logging is a form of forest degradation that alters canopy structure and function, with persistent ecological impacts following forest harvest. In this study, we employed airborne laser scanning in 2012 and 2014 to estimate three-dimensional changes in the forest canopy and understory structure and aboveground biomass following reduced-impact selective logging in a site in Eastern Amazon. Also, we developed a binary classification model to distinguish intact versus logged forests. We found that canopy gap frequency was significantly higher in logged versus intact forests even after 8 years (the time span of our study). In contrast, the understory of logged areas could not be distinguished from the understory of intact forests after 6–7 years of logging activities. Measuring new gap formation between LiDAR acquisitions in 2012 and 2014, we showed rates 2 to 7 times higher in logged areas compared to intact forests. New gaps were spatially clumped with 76 to 89% of new gaps within 5 m of prior logging damage. The biomass dynamics in areas logged between the two LiDAR acquisitions was clearly detected with an average estimated loss of −4.14 ± 0.76 MgC ha−1 y−1. In areas recovering from logging prior to the first acquisition, we estimated biomass gains close to zero. Together, our findings unravel the magnitude and duration of delayed impacts of selective logging in forest structural attributes, confirm the high potential of airborne LiDAR multitemporal data to characterize forest degradation in the tropics, and present a novel approach to forest classification using LiDAR data.

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Nutrient Allocation to Different Compartments of Age-Sequence Larch Plantations in China

Forests ◽

10.3390/f10090759 ◽

2019 ◽

Vol 10 (9) ◽

pp. 759

Author(s):

Hongxing Wang ◽

Dongsheng Chen ◽

Xiaomei Sun

Keyword(s):

Soil Nutrients ◽

Soil Nutrient ◽

Stand Age ◽

Nutrient Allocation ◽

Nutrient Losses ◽

Nutrient Return ◽

Nutrient Pools ◽

Clear Cut ◽

Nutrient Amounts ◽

Whole Tree Harvesting

Increased demand for forest-derived biomass has led to more intensive harvesting practices. However, the export of large nutrient quantities with the harvested biomass may lead to the depletion of soil nutrients. Therefore, improved knowledge concerning macronutrient allocation (N, P, K, Ca, and Mg) to different components in forests along age sequences is crucial for their sustainable management. In this study, we quantified nutrient allocation to different ecosystem components, including trees, understorey, forest floor, and different soil depths within a chronosequence (6-, 15-, 23-, and 35-year-old) of larch plantations in China. We then assessed the danger of significant nutrient losses from whole tree harvesting (WTH). Nutrient amounts in trees increased with stand age due to an increase in biomass. Stems accounted for 59%–72% of tree biomass and contained 40%–50% of total tree nutrients in the 15- to 35-year-old stands. The forest floor’s nutrient quantities increased from the 6- to 23-year-old stands and then decreased in the 35-year-old plantations. Conversely, most soil indicators initially declined from 15- to 23-year-old stands and then increased in the 35-year-old stand. The total nutrient stocks were greatest in the soil (0–40 cm), which accounted for about 93%–99% of total nutrients in the larch ecosystem. These data indicate that WTH causes nutrient losses about 2.0–2.5 times higher than stem-only harvesting, when thinning 15- or clear-cut harvesting 23- and 35-year-old stands. However, nutrient losses by WTH have little effect on the soil nutrient pools. Prolonging the crop cycle of larch plantations may be beneficial to improve nutrient return through litterfall and allow available soil nutrients to recover.

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Multi-temporal analysis of radiometric changes in satellite images of forest edges to infer selective-logging areas in the Amazon forest

Acta Amazonica ◽

10.1590/1809-4392201401073 ◽

2015 ◽

Vol 45 (1) ◽

pp. 35-44 ◽

Cited By ~ 2

Author(s):

Paulo Maurício Lima de Alencastro GRAÇA ◽

Francisco Dario MALDONADO ◽

João Roberto dos SANTOS ◽

Edwin Willem Hermanus KEIZER

Keyword(s):

Satellite Images ◽

Near Infrared ◽

Elevation Angle ◽

Temporal Analysis ◽

Selective Logging ◽

Amazon Forest ◽

Forest Edges ◽

Solar Elevation ◽

Multi Temporal ◽

Solar Elevation Angle

Radiometric changes observed in multi-temporal optical satellite images have an important role in efforts to characterize selective-logging areas. The aim of this study was to analyze the multi-temporal behavior of spectral-mixture responses in satellite images in simulated selective-logging areas in the Amazon forest, considering red/near-infrared spectral relationships. Forest edges were used to infer the selective-logging infrastructure using differently oriented edges in the transition between forest and deforested areas in satellite images. TM/Landsat-5 images acquired at three dates with different solar-illumination geometries were used in this analysis. The method assumed that the radiometric responses between forest with selective-logging effects and forest edges in contact with recent clear-cuts are related. The spatial frequency attributes of red/near infrared bands for edge areas were analyzed. Analysis of dispersion diagrams showed two groups of pixels that represent selective-logging areas. The attributes for size and radiometric distance representing these two groups were related to solar-elevation angle. The results suggest that detection of timber exploitation areas is limited because of the complexity of the selective-logging radiometric response. Thus, the accuracy of detecting selective logging can be influenced by the solar-elevation angle at the time of image acquisition. We conclude that images with lower solar-elevation angles are less reliable for delineation of selecting logging.

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Whale geography

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133317734103 ◽

2017 ◽

Vol 41 (5) ◽

pp. 676-685 ◽

Cited By ~ 1

Author(s):

Rianna Burnham

Keyword(s):

Population Dynamics ◽

Species Distribution ◽

Spatial Extent ◽

Niche Space ◽

Ambient Environment ◽

Species Survival ◽

Over Time ◽

Species Ecology

Typically, organism-based biogeographic studies consider distribution and abundance over time on various scales. However, to be comprehensive, factors of environment and habitat, energetics, morphology, and population dynamics should also be included. In addition, these studies should consider not only the spatial extent that an individual or species occupies or can roam within, but also the space over which an animal can extract and interpret information, a less well-defined element of niche space which largely shapes its movements or distribution. Understanding the processes that inform patterns of species distribution, both intrinsic and external to the animal, is key to understanding a species’ ecology. Here, we consider the biogeography of whales, given these ideas, with a particular focus on the acoustical components of their biology and landscape. Cetaceans use of sound to communicate, navigate and forage, and so interpret the soundscape, is a central consideration. It has important implications in a changing ambient environment and will increasingly influence species’ survival.

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Soil Nutrient Depletion Is Associated with the Presence of Burkholderia pseudomallei

Applied and Environmental Microbiology ◽

10.1128/aem.02538-16 ◽

2016 ◽

Vol 82 (24) ◽

pp. 7086-7092 ◽

Cited By ~ 21

Author(s):

Viriya Hantrakun ◽

Patpong Rongkard ◽

Malinee Oyuchua ◽

Premjit Amornchai ◽

Cherry Lim ◽

...

Keyword(s):

Organic Matter ◽

Physicochemical Properties ◽

Soil Properties ◽

Soil Nutrients ◽

Burkholderia Pseudomallei ◽

Agricultural Practices ◽

Rice Fields ◽

Soil Physicochemical Properties ◽

Content Type ◽

Calcium Magnesium

ABSTRACTBurkholderia pseudomalleiis a soil-dwelling bacterium and the cause of melioidosis, which kills an estimated 89,000 people per year worldwide. Agricultural workers are at high risk of infection due to repeated exposure to the bacterium. Little is known about the soil physicochemical properties associated with the presence or absence of the organism. Here, we evaluated the soil physicochemical properties and presence ofB. pseudomalleiin 6,100 soil samples collected from 61 rice fields in Thailand. The presence ofB. pseudomalleiwas negatively associated with the proportion of clay, proportion of moisture, level of salinity, percentage of organic matter, presence of cadmium, and nutrient levels (phosphorus, potassium, calcium, magnesium, and iron). The presence ofB. pseudomalleiwas not associated with the level of soil acidity (P= 0.54). In a multivariable logistic regression model, the presence ofB. pseudomalleiwas negatively associated with the percentage of organic matter (odds ratio [OR], 0.06; 95% confidence interval [CI], 0.01 to 0.47;P= 0.007), level of salinity (OR, 0.06; 95% CI, 0.01 to 0.74;P= 0.03), and percentage of soil moisture (OR, 0.81; 95% CI, 0.66 to 1.00;P= 0.05). Our study suggests thatB. pseudomalleithrives in rice fields that are nutrient depleted. Some agricultural practices result in a decline in soil nutrients, which may impact the presence and amount ofB. pseudomalleibacteria in affected areas.IMPORTANCEBurkholderia pseudomalleiis an environmental Gram-negative bacillus and the cause of melioidosis. Humans acquire the disease following skin inoculation, inhalation, or ingestion of the bacterium in the environment. The presence ofB. pseudomalleiin soil defines geographic regions where humans and livestock are at risk of melioidosis, yet little is known about the soil properties associated with the presence of the organism. We evaluated the soil properties and presence ofB. pseudomalleiin 61 rice fields in East, Central, and Northeast Thailand. We demonstrated that the organism was more commonly found in soils with lower levels of organic matter and nutrients, including phosphorus, potassium, calcium, magnesium, and iron. We also demonstrated that crop residue burning after harvest, which can reduce soil nutrients, was not uncommon. Some agricultural practices result in a decline in soil nutrients, which may impact the presence and amount ofB. pseudomalleibacteria in affected areas.

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Management-induced soil water erosion and nutrient losses in different land use in Mediterranean environment

10.5194/egusphere-egu2020-1151 ◽

2020 ◽

Author(s):

Igor Bogunovic ◽

Leon Josip Telak ◽

Paulo Pereira

Keyword(s):

Land Use ◽

Soil Erosion ◽

Soil Properties ◽

Soil Water ◽

Water Erosion ◽

Rainfall Simulation ◽

Soil Tillage ◽

Conservation Strategies ◽

Nutrient Losses ◽

Olive Orchard

Soil erosion by water is one of the most important degradation processes. Land use has important effects on soil properties, therefore it is key to identify the type of management that have more impacts and find solutions to mitigate it. In order to understand the effects of land use management on soil and soil erosion in the Istria region (Croatia), we studied the impacts of different agriculture practices (vineyard, cropland, and olive orchard) on soil properties and runoff. The simulated rainfall was carried out at 58 mm h&#8722;1 in the summer of 2018 (30% soil water content) for 30 min on 0.785 m2 circular plots. The results showed that bulk density was significantly higher in cropland plots than in the vineyard and olive orchard. Soil organic matter, mean weight diameter, and aggregate stability were significantly higher in olive orchard plots than in the vineyard and cropland. Runoff and sediment losses were higher in olive orchard compared to vineyard plots. Carbon, nitrogen, and phosphorus losses were highest in olive orchard plots with 3.9 kg ha-1, 405.2 g ha-1 and 73.6 g ha-1, respectively, while lower values were measured in the vineyard plots, where nutrients losses were lower with 0.9 kg ha-1, 73.8 g ha-1 and 6.5 g ha-1, respectively. No runoff was observed in cropland plots. Even with the highest measured values of runoff and erosion in the herbicide treated olive orchard, results indicate that both herbicide application and tillage represent a threat to the sustainability of Istrian soils. Vegetation cover on cropland reduces the runoff generation indicating the need for adoption of conservation strategies. In current management, vegetation removal should be avoided since it contributes to practice to reduce nutrient losses and increase the sustainability of the soils.&#160;Keywords: Soil water erosion, Soil tillage, Rainfall simulation, Agriculture land management, Mediterranean&#160;Acknowledgements&#160;This work was supported by Croatian Science Foundation through the project "Soil erosion and degradation in Croatia" (UIP-2017-05-7834) (SEDCRO).

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Soil and alfalfa response after amelioration of subsoil acidity in a fine sandy loam Podzol in Prince Edward Island

Canadian Journal of Soil Science ◽

10.4141/s00-005 ◽

2000 ◽

Vol 80 (4) ◽

pp. 607-615 ◽

Cited By ~ 2

Author(s):

M. R. Carter ◽

J. E. Richards

Keyword(s):

Soil Properties ◽

Medicago Sativa ◽

Prince Edward Island ◽

Sandy Loam ◽

Root Penetration ◽

Deep Placement ◽

Fine Sandy Loam ◽

Subsoil Acidity ◽

Medicago Sativa L ◽

Over Time

Subsoils in Prince Edward Island have poor chemical and often physical quality for root growth that may present a barrier to development of alfalfa (Medicago sativa L.). This study was conducted to characterise the response or benefit, on soil properties and alfalfa growth, of chemical amelioration and loosening of the subsoil. In 1987, the following three treatments were imposed on an acidic, fine sandy loam, Humo-Ferric Podzol: control (no subsoiling or lime), subsoiling alone, and subsoiling plus lime (5 Mg ha−1 dry CaCO3) mixed into the subsoil. The subsoiler was a Wye Double-Digger, a combined plough and rotary cultivator that facilitated the mixing of lime into the soil over the 230–480 mm depth. Management of the 0–200 mm soil depth was the same for all treatments. Growth of alfalfa and change in soil properties were monitored over time. In 2 of 4 yr (1991–1994), alfalfa yield was significantly (P < 0.05) increased by the subsoil plus lime treatment, compared with subsoiling alone or the control. Yield increases were related to periods of low growing season precipitation. Subsoil amelioration increased alfalfa root penetration (by 90 mm) and reduced leaf Mn concentration. Over an 8-yr period (1987–1994), soil exchangeable Ca was increased over fourfold, while exchangeable Al was decreased threefold in the ameliorated subsoil, compared with the control. Soil pH (in water) was increased from 4.8 to near 6.0. There was some evidence that liming of the topsoil improved the subsoil chemistry over time. Bulk density and penetrometer resistance contours, measured over time, indicated that the soil loosening effect was sustained throughout the soil profile over the duration of the study. Soil biological properties were not changed by the subsoil treatments. Key words: Subsoil acidity, podzol, lime, deep placement, alfalfa (Medicago sativa L.), cool-humid climate

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