Log Area Research Articles

Land use and land cover change analysis using satellite images in Gua Musang, Kelantan

Abstract The use of multisensor remote sensing to characterise forest structure has significant promise for mapping and understanding forest biological processes, making remote sensing an effective technology in detecting deforestation for forest management and monitoring. The aim of this study is to detect land use and land cover (LULC) changes due to deforestation at Gua Musang, Kelantan using satellite images. The Landsat 8 OLI satellite images were obtained from United State Geological Survey (USGS) for year 2017 to 2019. The supervised classification with maximum likelihood algorithm was applied for image classification to generate land use land cover categories. Then, LULC change detection between 2017, 2018 and 2019 were conducted to analyse the change and pattern. Based on the results, it shows the percentage of each land use changes within three (3) years from 2017 to 2019 for Landsat 8 OLI. Percentage of deforestation due to logging areas for year 2017 to 2019 is 5.95%. Percentage of forest area is 5.57%. For water bodies, the percentages just only cover 0.36% in 3 years. The highest land use change is no changes which is 88.12% happened towards the land from 2017 and 2019. This shows within three years there is no great changes at the area. The overall accuracy for each map is more than 80% which are acceptable. From the analysis, there were no significant changes of LULC during this period due to the increased of timber extraction, agricultural land expansion, urban growth, and poor governance structures.

Effects of reduced impact logging on population dynamics of Pseudopiptadenia suaveolens in Eastern Amazon, Brazil

Knowing the dynamics of the species natural populations is a strategy to improve its timber production and conservation, mainly through the effects caused by the reduced impact logging (RIL). Thus, the question is: what is the effect of RIL on the dynamics of Pseudopiptadenia suaveolens over time? The effect of RIL on the dynamics of P. suaveolens was evaluated based on survival, growth, recruitment, basal area and density of individuals ? 45 cm from Diameter to Breast Height (DBH at 1.30 m from the ground) in a thirteen-year chronosequence. Five Annual Production Units (APU) were inventoried, where four were harvested in different years (2002; 2004; 2008 and 2010) and one not harvested. The highest mortality rate occurred at five (6.6% year-1) and seven (5.2% year-1) years after RIL. At eleven (2.4% year-1) and thirteen (1.0 % year-1) years, mortality rates did not differ significantly between themselves and in relation to the control area (not harvested). The recruitment rate was significantly higher seven years after logging (7.7% year-1) when compared to the other years. In logged areas, trees with DBH ? 75 cm account for the majority of deaths, although there was no significant difference between diameter classes, which were minimally influenced by RIL. Mortality and growth rates of P. suaveolens by diametric class did not show significant difference, however, they were minimally influenced by the RIL.

New technological solutions for waterlogged forests by cable yarding

The article proposes new technological techniques for clear cutting in swampy areas using standing skylines, new construction of yarder and the technology of its operation. As a result of the research on using the Larix 3T-500 cable yarder in winter and summer, the operational negative peculiarities of tower yarder in waterlogged forests were identified. Analysing data on experimental comparative time studies, some measures to reduce the negative effect of the identified features on yarding, felling, lateral yarding were worked out. General recommendations for work performance in swampy logging areas were developed. Based on the initial data for each bundle (yarding distance, lateral yarding distance, average volume of the bundle, etc.) the calculation in the MathCad program was performed and a regression dependence of the yarder performance was obtained. Obtained numerical data on comparative time studies of the working cycle operations were summarized in bar charts, taking into account the loss of time on operations.

Pharmacokinetics, Bioequivalence, and Safety Studies of Amlodipine Besylate in Healthy Subjects

This study aimed to evaluate the bioequivalence of 2 amlodipine besylate tablet formulations, a generic formulation and an original formulation, and to investigate their pharmacokinetic and safety profiles. This study was designed as a randomized, open-label, single-dose, crossover, dual-period study and was divided into fasting and postprandial human bioequivalence trials. In the first trial after overnight fasting, 28 subjects were given 5-mg amlodipine besylate tablets via oral administration, and blood specimens were obtained up to 144 hours after dosing; another 28 subjects had a high-fat meal 1hour before drug administration and proceeded the same as the fasting trial. Bioequivalence was evaluated using 90%CIs for the ratio test/reference of log area under the concentration-time curve (AUC) from time 0 to the last quantifiable concentration, log AUC from time 0 to infinity, and log peak concentration. The plasma concentrations were measured by high-performance liquid chromatography-tandem mass spectrometry. The safety was assessed throughout the study. The results show that no significant differences were observed between the pharmacokinetic profiles of the test and reference amlodipine besylate tablets in the fasting and postprandial trials. The 90%CIs of the peak concentration, AUC from time 0 to the last quantifiable concentration and AUC from time 0 to infinity of amlodipine in the 2 trials were within the commonly accepted bioequivalence criteria of 80% to 125%. Compared with the pharmacokinetic parameters of the fasting and postprandial trials, food had no significant effect on exposure of amlodipine besylate. There was no significant difference in safety statistical results between the 2 groups. The results suggest that generic and original amlodipine besylate tablets are bioequivalent with similar safety profiles.

Optimal route design for an airship collecting and delivering logs in difficult environmental conditions

In this paper, we consider the problem of computing the optimal route to be followed by an airship collecting logs in order to bring them to a sawmill. The problem is separated into two phases. In the first one, we aim to determine the touring order and the number of logs to be collected for each round-trip between the logging area and the sawmill. The strategy is designed by taking into account the airship sensitivity to atmospheric conditions, which makes the cost to join a heap of logs highly dependent on the vehicle orientation with respect to the wind direction. The determination is achieved by solving an instance of a combinatorial problem called Asymmetric Capacitated Vehicle Routing Problem (ACVRP). We introduce airship enhanced Dubins paths taking the wind influence into account to compare more realistic transition costs easily. During the second phase, the resulting heap-to-heap trajectories are calculated so as to minimize the travel cost consisting of the time and energy consumption. The equations of generic nonlinear airship dynamics are derived and used for trajectory optimization. The resulting performances are illustrated with a mountainous scenario with varying windspeed. The overall scheme forms an innovative approach to solve issues related to typical airship missions.

Considerations in the protection of marsupial gliders and other mature-forest dependent fauna in areas of intensive logging in the tall forests of Victoria, Australia

Context The tall forests of Victoria, Australia, which are available for logging, are foreshadowed to be converted from mature forest to hostile environments for mature-forest dependent species by 2030. This has occurred within a 60-year time-frame since the advent of industrial-scale logging in the region. In this light, Protection Areas (PAs) of approximately 100 ha have been implemented to protect habitat with high density populations of Yellow-bellied Gliders (Petaurus australis) and Southern Greater Gliders (Petauroides volans). Aims and methods Ten considerations are provided to guide location and design of PAs, and to provide set asides and other forms of protection for mature-forest dependent species in the context of the temporal and spatial scale of logging activity. Key results Considerations are grouped into Overall approach (precautionary), Survey records and habitat attributes (occurrence, habitat, vegetation types), Size and shape considerations (edge and fragmentation effects); Management history (logging and fire), and Boundary considerations (context and conditions). In addition, set asides encompassing home ranges; and high levels of basal area retention, are also required in the remainder of planned logging coupes. Conclusions Addressing these considerations in PAs, in set asides and in retention will provide some protection for mature-forest dependent species, but will be insufficient without ecologically sustainable forest management at the coupe level, for the sustained yield of all habitat components of these forests. Implications The conservation of mature-forest dependent species in the context of an ongoing timber industry requires logging return times well beyond current expectations, resulting in a substantial reduction in resource commitment to industry.

Post-fire dynamics of tree vegetation in forests with and without a history of selective logging in the Eastern Amazon

Worldwide, forests are susceptible to fire. Forests with fire and selective logging interactions require monitoring and evaluation. This study evaluated the phytosociology and dynamics of tree vegetation in a disturbed forest (DF) and an undisturbed forest (UF) in selective logging areas affected by fire, in the Brazilian East Amazon. All trees with DBH ≥ 5 cm were measured and identified botanically in 93 plots (5 X 50 m) in the DF area and 58 plots (5 X 50 m) in the UF area, in 2010 (before logging), 2011, 2015 and 2017 (two years after the fire). Analysis of species and tree composition, diversity, similarity, mortality and recruitment were carried out. The fire affected the DF and UF areas in a similar proportion in terms of trees loss and basal area, intensifying the mortality rate. In the short term (2 years), the fire did not cause a significant reduction in species diversity, but there was a tendency towards a similarity loss in species composition in the area disturbed by logging. Subsequent assessments are necessary to understand the forest's recovery mechanisms.

Drought years promote bark beetle outbreaks in Mexican forests of Abies religiosa and Pinus pseudostrobus

Climate change is an important risk factor for forest ecosystems through alteration of forest disturbance regimes such as bark beetle outbreaks, which in some places now are more successfully attacking host trees weakened by hotter drought events. In Mexico, ties between climate and amplified outbreaks of bark beetles have begun to be documented, although these relationships are not entirely clear. This project aims to identify the geographic patterning and relations between climate and bark beetle outbreaks in Abies religiosa and Pinus pseudostrobus populations located in the Trans-Mexican Volcanic Belt region. We used: 1) a database of phytosanitary logging authorizations and locations issued to enable salvage logging of trees infested or killed by bark beetle outbreaks from 2009 to 2018; 2) a previously developed gridded database of contemporary suitable climatic habitat of these tree species that will be lost by 2060 to determine if outbreaks occurred in sites with climatic habitat lost; and 3) elevation values to determine if outbreaks occur at xeric limits (drought limits) of tree hosts. Climate analysis was conducted with TerraClimate data using PDSI (Palmer’s Drought Severity Index) values. We find that bark beetle outbreaks do not necessarily occur at sites where models project that both species will lose suitable climatic habitat. For A. religiosa (Sacred Fir), of the 4091 ha treated by sanitary logging, 40% occurs between 3000 and 3100 m of elevation, where the pure and relatively better-preserved Sacred Fir stands are found. For P. pseudostrobus, more than 54% of the sanitary logging area (4664 ha) ranges from 2200 to 2400 m a.s.l., which coincides with the lower elevation limit (xeric limit) of the natural distribution of the species. Regarding relationships with PDSI, for A. religiosa there was a one-year lag between the year of mortality (expressed by the year of the phytosanitary logging authorization) and the year with the most negative (driest) PDSI anomaly (one year before), while for Pinus pseudostrobus, phytosanitary logging authorizations were concentrated in the driest year. An investigation that considers more variables, especially anthropogenic factors, is necessary to be able to better understand the dynamics of forest pests and prevent unusual outbreaks induced by expected climate-change-amplified droughts.

Change Detection of Selective Logging in the Brazilian Amazon Using X-Band SAR Data and Pre-Trained Convolutional Neural Networks

It is estimated that, in the Brazilian Amazon, forest degradation contributes three times more than deforestation for the loss of gross above-ground biomass. Degradation, in particular those caused by selective logging, result in features whose detection is a challenge to remote sensing, due to its size, space configuration, and geographical distribution. From the available remote sensing technologies, SAR data allow monitoring even during adverse atmospheric conditions. The aim of this study was to test different pre-trained models of Convolutional Neural Networks (CNNs) for change detection associated with forest degradation in bitemporal products obtained from a pair of SAR COSMO-SkyMed images acquired before and after logging in the Jamari National Forest. This area contains areas of legal and illegal logging, and to test the influence of the speckle effect on the result of this classification by applying the classification methodology on previously filtered and unfiltered images, comparing the results. A method of cluster detections was also presented, based on density-based spatial clustering of applications with noise (DBSCAN), which would make it possible, for example, to guide inspection actions and allow the calculation of the intensity of exploitation (IEX). Although the differences between the tested models were in the order of less than 5%, the tests on the RGB composition (where R = coefficient of variation; G = minimum values; and B = gradient) presented a slightly better performance compared to the others in terms of the number of correct classifications for selective logging, in particular using the model Painters (accuracy = 92%) even in the generalization tests, which presented an overall accuracy of 87%, and in the test on RGB from the unfiltered image pair (accuracy of 90%). These results indicate that multitemporal X-band SAR data have the potential for monitoring selective logging in tropical forests, especially in combination with CNN techniques.

An object-based approach to detect tree stumps in a selective logging area using Unmanned Aerial Vehicle imagery

Acquiring tree-stump information is important to support post-harvest site assessment. Unmanned Aerial Vehicles (UAVs) have been widely used as a tool for analyzing selective logging impacts in forest area sites. One of the potential use of UAV imagery data for analyzing the impact of selective logging is by obtaining tree stump information. Feature extraction and segmentation images to extract stumps from a UAV scene of a forested area in Ulu Jelai, Pahang provides a quick, automated method for identifying stumps. This research implemented a technique for detecting, segmenting, classifying, and measuring tree stumps by using the Multiresolution Segmentation Algorithm method. This study assessed the capability of an object-based approach on image detection to segment and merge the stumps after selective logging practice on UAV imagery with a scale of 0.06-meter resolution. The results revealed that the tree-stumps were detected with an accuracy of 70% and stumps classification were detected with 80% accuracy validated with the ground points. The accuracy is acceptable for data acquiring after 6 months of logging activities. The findings of this study are promising and can lead to increase support for a more cost-effective and systematic selective logging in the future. An effective management system can help related authorities and agencies to develop and maintain the selective logging technique towards sustainable forest management. Keywords: machine learning, object-based approach, remote sensing, selective logging, stump detection, UAV

Damage Cost/Value Clustering in Timber Harvesting Decision Making for Sustainable Forest Management

The most important factor to ensure forest regrowth strongly relies on minimizing damage as well as maintaining an adequate quantity and quality of residual stands. Currently, most of the Malaysian concessions are applying the Selective Management System (SMS). The SMS had been introduced about 40 years ago and various studies discovered that it contributes a negative impact on the forest. Thus, revision and adoption of an appropriate harvesting method are required. The main objective of this study is to propose a new method that promotes forest regrowth and reduces damages due to logging activities for Sustainable Forest Management (SFM). The two primary elements introduce in this new method are 1) to determine the minimum damage cost/value to the residual trees according to tree felling direction and 2) on the division of logging area into clusters where only certain clusters will be affected in a logging operation and the rest are conserved. The overall results of this study proven that the analysis of potential logged value, productions, damage value, and damage volume by dividing forest into clusters able to minimize damage and maintain forest regeneration.

Sun bears use 14‐year‐old previously logged forest more than primary forest in Sabah, Malaysia

AbstractSun bears (Helarctos malayanus), arguably the least‐known bear species, are endemic to Southeast Asia and are believed to be in rapid decline due to forest loss and poaching, which are severe threats across this region. It has been asserted that, unlike other forest‐dependent, omnivorous bears, sun bears are especially sensitive to changes in forest composition and canopy closure because they often feed on fruits in the canopy. We investigated habitat use of sun bears in a region of Sabah, Malaysian Borneo, containing primary forest adjacent to a 14‐yr‐old selectively logged forest. We used strip transects to quantify trees that sun bears climbed to forage or rest; these were easily recognized by distinctive claw marks. We found 1.8× the density of bear‐climbed trees in the logged vs. the primary forest. Dead wood, a home for various insects eaten by sun bears, was more common in logged forests. Except during masting years, when fruits are exceptionally abundant in this area, sun bears commonly consume termites and bees, both of which were more common in the logged forest and had a positive effect on sun bear presence. Sun bear presence was also positively associated with canopy closure, which on average was higher in primary forest, but some portions of logged forest had very high canopy cover. The logged forest had higher vegetative greenness, which up to a point was attractive to bears, but very high greenness, likely indicative of thick underbrush, appeared to be less attractive. These results indicate that previously logged areas can be valuable habitats for sun bears, providing rich supplies of food––both fruits and insects. A number of recent biodiversity surveys using camera traps have also shown high use of logged areas by sun bears, but here we connected this use to food resources. Conservation of this species is better served by appreciating its omnivorous diet and adaptiveness to varying habitats and thus recognizing the importance of preventing logged areas from deteriorating into agriculture. We warn against focusing only on saving primary forests, and predicting declines of this species from forest cutting, without considering forest regeneration.

Desiderata for the development of next-generation electronic health record phenotype libraries.

BackgroundHigh-quality phenotype definitions are desirable to enable the extraction of patient cohorts from large electronic health record repositories and are characterized by properties such as portability, reproducibility, and validity. Phenotype libraries, where definitions are stored, have the potential to contribute significantly to the quality of the definitions they host. In this work, we present a set of desiderata for the design of a next-generation phenotype library that is able to ensure the quality of hosted definitions by combining the functionality currently offered by disparate tooling.MethodsA group of researchers examined work to date on phenotype models, implementation, and validation, as well as contemporary phenotype libraries developed as a part of their own phenomics communities. Existing phenotype frameworks were also examined. This work was translated and refined by all the authors into a set of best practices.ResultsWe present 14 library desiderata that promote high-quality phenotype definitions, in the areas of modelling, logging, validation, and sharing and warehousing.ConclusionsThere are a number of choices to be made when constructing phenotype libraries. Our considerations distil the best practices in the field and include pointers towards their further development to support portable, reproducible, and clinically valid phenotype design. The provision of high-quality phenotype definitions enables electronic health record data to be more effectively used in medical domains.

Long‐term impacts of forest disturbances: Comparing cumulative effects of clearcut logging versus landslide on stream conditions and abundance of a headwater stonefly Scopura montana

Abstract When forest disturbance impacts adjacent headwater streams, the recovery of habitat conditions and populations can take over several decades. Thus, considering long‐term, historical legacies of forest disturbances is key for understanding and managing forest–stream linkages. We focused on small‐scale forest disturbances such as small‐block harvesting and landslides. We compared the long‐term (past 100 years) cumulative effects between the anthropogenic and natural forest disturbances on stream conditions and the abundance of a headwater specialist, Scopura montana (Plecoptera: Scopuridae). Sampling was conducted in 10 m reaches of 39 first‐order streams with a catchment area up to 5.9 ha during late summer in central Japan. We quantified past clearcut logging areas using plantation records of each harvest block and past landslide areas from contour maps within each catchment. Piecewise structural equation models using the cumulative area of each forest disturbance as an independent variable, revealed different indirect effects of clearcut logging (average area: 1.74 ha) and landslides (0.21 ha) on S. montana abundance through modified stream conditions. Canopy openness and wetted channel width were higher with a larger logged area, and S. montana abundance was lower with higher water temperature (daily maximum). When the magnitude of clearcut logging was similar to the landslide area (<0.77 ha), the negative relationship between water temperature and S. montana abundance was also significant in the model. Streambed roughness and wetted channel width were greater with larger landslide area but there were no significant links between stream conditions and S. montana abundance. Our results suggest that clearcut logging can cause long‐term impacts by exposing the stream surface to solar radiation owing to delayed canopy closure. The preference of S. montana is for cold water conditions in summer. Controlling forest harvesting along streams could benefit forest–stream management, as could including consideration of disturbance‐driven cycles for sustaining headwater populations.

Construction of pervious concrete pavement stretch, Ahmedabad, India – Case study

Rapidly growing and uncontrolled changes in the natural landscape due to human intervention has created a serious problem of rainwater harvesting in many Indian cities. Rainwater is seen getting wasted on the roads due to lack of proper design of drainage system. Construction of Pervious concrete pavement (PCP) is one of the best method to solve this problem. The pervious nature of the pavement is suggested to act as a drainage pipe and the water accumulated on the road or pavements drains out immediately. Therefore, an attempt has been made for the construction of PCP in this present study. The PCP was constructed at Nirma University campus, Ahmedabad, India for study purpose. The size of PCP stretch was 3 m × 10 m. The details of construction methodology and material used for the construction of PCP are included in this paper. In addition to that, properties of pervious concrete (PC) such as void ratio, compressive strength, permeability and density were evaluated and compared with field investigation results. The 28 days results of PC field cores and cast specimens achieved similar range for compressive strength and void ratio. Moreover, maintenance schedule was prepared for the supervision of PCP. The infiltration rate was measured at different intervals to determine if there was clogging in the PCP. Based on the results of this investigation, it is seen that there is successful drainage performance of the PCP, demonstrating the possibility of construction of such pavements in the water logged areas of India.

The Effect of Forest Management on the Avifauna of a Brazilian Dry Forest

The conversion of tropical habitats has dramatic implications on biodiversity and represents one of the greatest conservation challenges of our time. Seasonally Dry Tropical Forests (SDTF), which are disjointly distributed throughout the Neotropics, are especially susceptible to human activities. The Caatinga Dry Forest, located in the semi-arid interior of northeastern Brazil, represents not only the largest and most biologically diverse nucleus of SDTF, but also the world’s most densely populated semi-arid region, with ever-growing pressure on its natural resources. To prevent illegal logging, conservation agencies looked at forest management, where an area is divided in smaller stands which are gradually logged and allowed to regrow for a period of time, when a new cutting cycle should reinitiate. The impacts of these management schemes on biodiversity, however, remain largely untested. We conducted standardized avian surveys to evaluate the effects of forest management on the avian community at a 1,670 ha privately owned property located on the Chapada do Araripe, northeastern Brazil. This area was divided in 22 forest stands, half of which had already been logged at the time of our sampling, creating a gradient of logged and natural forests and an 11-yr chrono-sequence of forest regeneration. Our results show that logged areas present fewer individuals, fewer species, and different avian assemblages than unlogged forests. Such differences are mostly driven by forest-dependent species, which were overwhelmingly affected by forest management. Our results show that although logged forests tend to recover its height after a decade, they do not recover the originally forest cover, measured by the Normalized Difference Vegetation Index. Likewise, decade-long recovering stands continue to show lower species richness, lower bird abundance, and different avian composition than unlogged forests. We identified a set of bird species that are more affected by forest management (ecological losers) and a group of birds that apparently benefit from the referred changes in land use (ecological winners). We conclude that completely managing an entire area may cause the extirpation of several forest-dependent species. We therefore suggest keeping logged and unlogged plots intermingled, to avoid local extinctions and the complete modification of the original avifauna.

Characteristics of the spatial and temporal distribution of fire regime in ONE OF the most fire prone Region Of The Russian Far East

Wildfires affect the structure and distribution of vegetation all over the globe and have their own specifics in different regions. In this study, we considered the spatial and temporal distribution of fires in the Jewish Autonomous Region (JAR), which is the most fire-prone area of the Russian Far East. Using data from the Department of Natural Resources of the Jewish Autonomous Region, fires and burned areas for more than 40 years were analyzed. The average annual number of fires is near 100, and the average area of one fire is 134 hectares, which is significantly higher compared to other regions of Russia. The largest number of fires and fires with the greatest extent took place in 1975. The intra-annual distribution of fires is bimodal and depends on the climate characteristics of the region. Mapping of burning areas showed that most of the fires occurred near settlements and along roads. The main centers of fire ignition were areas with a large number of small fires (no more than 5 hectares), located within several types of locations: (1) asphalt and dirt roads, railroads and river valleys near settlements; (2) areas of former logging that have several large burned spots of more than 300 hectares; (3) plains with a high concentration of fires over a large region; and (4) small burned spots on the mountain slopes, along the field roads and small rivers. Regions with different degree of fire exposure were identified. Sedge-reed mixed grassy meadows and Agricultural land with shaded meadows are the plant formations most prone to wildfires. At the same time, more fires were detected in Cedar-deciduous forests as well as Oak and black birch forests. The findings are useful for environmental protection agencies in planning fire management strategies, optimizing the fire services and firefighting actions.

Bat diversity in the Banpale forest, Pokhara, Nepal during spring season

Bat research in Nepal is limited and most areas remain to be explored. Sparse research has been conducted in the Banpale forest and to improve the understanding of bat diversity, an updated species checklist was prepared. Trapping surveys using mist nets were conducted at four different locations in the forest from March to May 2018. This survey identified 55 individuals belonging to eight species within eight genera and four families. Trapping locations near less disturbed forest edges and water resources were found to have higher bat diversity compared to highly disturbed areas (e.g., landslides and logging areas). With information from survey and secondary source, we conclude that Banpale forest harbours 10 of the 53 bat species found in Nepal. We recommend adopting practices to conserve the forest from landslides and minimizing illegal logging to conserve bat forest habitats.

Regional variation of electrical and lightning properties of thunderclouds during the pre-monsoon season over the north-eastern and eastern part of India

Regional variation of electrical and lightning properties of thunderclouds is investigated by using simultaneous observations of electric field mill (EFM-100) and lightning detector (LD-350) in synergy with their radiance and bulk microphysical properties. The study is carried out over Kohima in the north-eastern and over Rampurhat in the eastern part of India (20o-30o N, 85o-96o E), during the pre-monsoon season (March–May) of 2017–2018. The occurrence of EFM-100 detected thunderclouds is found to be more over Kohima (111) compared to Rampurhat (88). Whereas, the average number of lightning flash is much higher over Rampurhat (~542 flash/thundercloud) compared to Kohima (~32 flash/thundercloud). Over both the regions, the maximum occurrence of thunderclouds is found during afternoon to evening hours. The upper whisker value in the box plot shows that thunderclouds over Rampurhat are associated with higher CAPE value (Kohima: 1100 J Kg−1; Rampurhat: 5000 J Kg−1). The diurnal variation of CAPE supports relatively early occurrence of thunderclouds over Kohima. Thunderclouds over Rampurhat persists for relatively longer duration. It is observed that overall percentage occurrence of CG lightning is more over Kohima (Kohima: −CG: 28.09% & +CG: 09.74%; Rampurhat (–CG: 12.33% & +CG: 08.60%), with relatively higher −CG lightning compared to +CG, over both the stations. On the contrary, the occurrence of IC lightning is more over Rampurhat (Rampurhat: −IC: 31.75% & +IC: 47.30%; Kohima: −IC: 36.44% & +IC: 25.72%). Over Kohima occurrence of −IC is more than the +IC, whereas over Rampurhat, the occurrence of +IC is more than −IC. The overall higher occurrence of total negative and positive discharges over Kohima and Rampurhat respectively is consistence with EFM observations. The prevalence of positive/negative discharge suggests the presence of a tripole charge structure within thunderclouds over both the regions. The upper whisker value in the box plots revels higher CG flash density, IC:CG and larger log(area) over Rampurhat (Kohima: 3.0 × 10−3 flash km−2 h−1 and Rampurhat: 4.25 × 10−3 flash km−2 h−1; Kohima: 7 and Rampurhat: 15; Kohima: 10.5 km2 and Rampurhat: 11.5 km2). The lower whisker value of cloud top temperature reveals prevalence of colder thunderclouds over Rampurhat (Kohima: 220 K; Rampurhat: 184 K). The thunderclouds over Rampurhat are found to be associated with stronger updrafts and mixed-phase processes. The study reveals that, over these two regions, the electrical and lightning properties have distinct characteristics.

Effects of low-impact logging on understory birds in the Brazilian Amazon

Tropical forests have a great potential for the exploitation of natural resources. Among the economic activities that depend on forest resources, timber production is the most important one. Nevertheless, these activities may negatively affect wildlife, the availability of natural resources, and ecosystem process. Here we analysed the effects of low-impact logging on understory bird species richness, number of individuals captured, species composition, and assemblage structure in central Brazilian Amazon. We compared logged and unlogged areas over a period of three years (from August 2014 to May 2017). We captured a total of 180 birds and 42 species (20 families) in the logged area and 226 birds and 49 species (20 families) in the unlogged area. Bird assemblage structure in the logged area changed more intensely over the three years of study and became more similar to the assemblage found in the unlogged area. The degree of similarity (Jaccard’s index) in species composition between logged and unlogged areas increased from 18% in the third year to 39% in the fifth year after logging. The results suggest that the minor effects of low-impact logging were reduced a few years after the disturbance, probably due to ecological succession. The proximity of logged and unlogged areas and the reduced impact in the study site may facilitate the recovery of the bird assemblage after the disturbance.