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Symmetry ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2260
Author(s):  
Jialei Zhan ◽  
Yaowen Hu ◽  
Weiwei Cai ◽  
Guoxiong Zhou ◽  
Liujun Li

The target detection of smoke through remote sensing images obtained by means of unmanned aerial vehicles (UAVs) can be effective for monitoring early forest fires. However, smoke targets in UAV images are often small and difficult to detect accurately. In this paper, we use YOLOX-L as a baseline and propose a forest smoke detection network based on the parallel spatial domain attention mechanism and a small-scale transformer feature pyramid network (PDAM–STPNNet). First, to enhance the proportion of small forest fire smoke targets in the dataset, we use component stitching data enhancement to generate small forest fire smoke target images in a scaled collage. Then, to fully extract the texture features of smoke, we propose a parallel spatial domain attention mechanism (PDAM) to consider the local and global textures of smoke with symmetry. Finally, we propose a small-scale transformer feature pyramid network (STPN), which uses the transformer encoder to replace all CSP_2 blocks in turn on top of YOLOX-L’s FPN, effectively improving the model’s ability to extract small-target smoke. We validated the effectiveness of our model with recourse to a home-made dataset, the Wildfire Observers and Smoke Recognition Homepage, and the Bowfire dataset. The experiments show that our method has a better detection capability than previous methods.


2021 ◽  
Vol 11 (3) ◽  
pp. 130-139
Author(s):  
Mikhail Drapalyuk ◽  
Nikita Ushakov ◽  
Nikolai Jujukin ◽  
Aleksey Zhuravlev

The analysis of sowing methods and existing types of seeders, which are used in forestry and agrotechnical complexes, as well as patent materials, is given. Analysis of domestic designs of SLP-M, SLU-5-20 and "Litva-25" seeders, intended for sowing small forest seeds in nurseries and open ground, showed that they are energy-intensive and do not always ensure the embedding of seeds in moist soil. The perspective directions of resource conservation in agriculture have been considered: sowing using "no-till" or "mini-do" technology, ensuring sowing of seeds in untreated and minimally cultivated soil. The combined seeder AGRATORDK is equipped with a disc cultivator and a seeder with gouters. The RAPIDRDA-450S seeder from VADERSTAD has spherical discs that cultivate soil in one pass. The presented methods of sowing and seeding devices have a significant drawback - the necessity of additional working bodies with a high probability of getting into the grooves of dry soil, moving the top layer of soil "back and forth." A gouter which can change the angle of entering the soil and planting depths of small forest seeds was developed. Preliminary laboratory studies have shown the operability of gouter mock-up specimen and the ability to cut the seed furrow by cutting out a layer of soil with void formation above the bottom of the seed furrow, into which seeds were fed through tubes from funnels. The seeds were embedded with a layer of soil under the influence of its own gravity


Zootaxa ◽  
2021 ◽  
Vol 5047 (5) ◽  
pp. 531-546
Author(s):  
GIOVANNI A. CHAVES-PORTILLA ◽  
ERIKA NATHALIA SALAZAR ◽  
JOSÉ GIL-ACERO ◽  
ADRIANA DORADO-CORREA ◽  
ROBERTO MÁRQUEZ ◽  
...  

A new species of Andinobates (Dendrobatidae) is described from the East Andes of Colombia, just 37 km away from the Colombian capital, Bogotá. Andinobates supata sp. nov., represents the second known species of yellow Andinobates, and can be distinguished from the other, Andinobates tolimensis, by an unique combination of ventral and dorsal color patterns. Our phylogenetic analyses, based on ≈ 1120 bp from two mitochondrial markers (16S rRNA and cytochrome b) showed that this new taxon is sister to a clade formed by A. cassidyhornae, A. bombetes, A. opisthomelas, A. tolimensis and A. virolinensis. The new species appears to be restricted to a handful of small forest fragments (<10 ha) distributed in no more than 5 km2, between 1800–2000 m elevation, where the human activity is high. In addition, more than 90% of the original forest has been logged at the type locality, and its watersheds receive considerable agrochemical discharges. Altogether, the evidence suggests that this new species should be listed as Critically Endangered and should receive immediate attention regarding basic research and urgent conservation measures.  


2021 ◽  
Vol 125 ◽  
pp. 25-38
Author(s):  
Špela Ščap ◽  
Darja Stare ◽  
Nike Krajnc ◽  
Matevž Triplat

A survey conducted in 2019 covered 544 randomly selected forest owners. More than half of the forest owners own a forest estate ranging from 1 to 4.99 ha. For 62 % of respondents, the primary purpose of forest management is to harvest wood for their own needs. In 2015%2019, 71 % of respondents carried out felling and skidding in their forests. In total, approximately 50,000 m3 of wood was felled (24 m3 /ha or 141 m3 per holding). The largest volumes were felled by private owners with small forest holdings (up to 0.99 ha), on average 41.4 m3 /ha. There were statistically significant differences between the size of the forest holding and the average volume of annual felling. Furthermore, there were no statistically significant differences in felling intensity between male and female forest owners. The survey found that professional contractors carried out 41 % of felling and harvesting. Furthermore, there were significant differences between the size of the private forest estate and the method of performing forest operations. The results showed that the largest share of private owners who carry out all felling and skidding with the help of hired contractors is in the size class of forest holdings from 5 to 9.99 ha. The study did not confirm statistically significant differences in the intensity of felling between male and female private forest owners.


2021 ◽  
Vol 97 (2) ◽  
pp. 315-343
Author(s):  
Francesco Belluardo ◽  
Darwin Díaz Quirós ◽  
Javier Lobón-Rovira ◽  
Gonçalo M. Rosa ◽  
Malalatiana Rasoazanany ◽  
...  

Madagascar has historically suffered from high fragmentation of forested habitats, often leading to biodiversity loss. Neverthless, forest fragments still retain high levels of biological diversity. The Haute Matsiatra Region (south-eastern Madagascar) hosts the renowned Andringitra National Park and several surrounding isolated forest fragments embedded in a matrix of human-dominated landscape. During a herpetological survey conducted in the Region, we visited a total of 25 sites. We applied a molecular taxonomic approach to identify the collected material and generate new reference sequences to improve the molecular identification of Malagasy herpetofauna. We identified a total of 28 amphibian and 38 squamate taxa and provided a systematic account for each one of them. Nine of the identified taxa are candidate species, amongst which one was newly identified. We extended the known distributional range of 21 taxa (nine amphibians and 12 squamates). Although the largest forest fragments hold a higher number of species, we also detected a relatively high herpetological diversity in small patches. Our results highlight the importance of investigating small forest fragments to contribute to a better understanding of the patterns of diversity and distribution of the amphibians and reptiles of Madagascar.


Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 729
Author(s):  
Mario Šporčić ◽  
Marijan Šušnjar ◽  
Zdravko Pandur ◽  
Marin Bačić ◽  
David Mijoč ◽  
...  

Skidders, as self-propelled machines designed to transport trees or parts of trees by trailing or dragging it from the woods to a landing area, are still extensively used as the main wood extraction equipment in most of the Europe and worldwide. The high price of new machines (and even higher for CTL technology) makes the second-hand skidder market very interesting and appealing, especially for small forest owners and forestry contractors. So, this paper reports on a survey of used skidders available for purchase on the European market. Up-to-date empirical data was gathered by the analysis of the offerings on the main online marketplaces, i.e., specialized websites. The study included skidder make and model, variation in their age, annual usage and resale prices. The survey identified a total of 163 second-hand skidders and the results pointed out the prevalence of small-size machines (<110 kW), the average annual use (after excluding 1 year old machines from calculation) of 863 hours per year and the average re-sale price of about 65,000 EUR. Skidders are most commonly re-sold at an age of 16 years and the calculated price models show that skidder age is a stronger predictor of their value, i.e., resale price, than the total machine working hours. In the concluding section, paper also includes some reflections on possible future trends and perspectives of skidding technology in forestry.


2021 ◽  
Vol 490 ◽  
pp. 119076
Author(s):  
Ueli Schmid ◽  
Christof Bigler ◽  
Monika Frehner ◽  
Harald Bugmann

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