Identifying High Value Arboreal Habitat in forested areas using high-resolution digital imagery

2016 ◽  
Vol 22 (4) ◽  
pp. 367
Author(s):  
Nigel Cotsell ◽  
Mark Fisher ◽  
David Scotts ◽  
Mark Cameron

Old-growth forest is recognised as a high-value habitat in conservation assessment programs because of its importance to hollow-dependent species. Previous mapping undertaken at regional scales does not map patches of old forest smaller than 5 ha. While small patches of old forest may not be as ecologically important as large areas they provide opportunities for connectivity and specific habitat resources for arboreal wildlife within a broader landscape matrix. Previously, smaller patches of old forest have been overlooked because the tools have not been available to map at finer scales. This study incorporates a methodology using recent advances in technology, including aerial photography, to map old forest at a fine scale for the purposes of land-use assessment and planning. The term ‘High Value Arboreal Habitat’ is introduced to convey the ecological importance of hollow-bearing trees as part of a wider identification and mapping of high-value habitats across the landscape. The assessment was undertaken across the forested areas of the Coffs Harbour Local Government Area using high-resolution digital imagery. It is anticipated that the High Value Arboreal Habitat mapping process will be adopted by a range of stakeholders and natural resource managers to better manage and conserve these old forests across the landscape whatever their size.

2020 ◽  
Vol 11 (4) ◽  
pp. 93-109
Author(s):  
Stavros KOLIOS ◽  
◽  
George NTOGAS ◽  
Efthimios ZERVAS ◽  
◽  
...  

The scope of the study is to detect spatial changes in the forested areas over six decades (1945 - 2010) of two completely different landscapes in Greece (pilot areas). The first pilot area is Kastoria which is a relatively remote and mountainous area located northwestern on the Greek peninsula, while the second one is Propontida which is a coastal area in the Chalkidiki peninsula (central Macedonia, Greece). High resolution orthorectified aerial images are used to detect the general types (classes) of land use/land cover (LULC) in these pilot areas. The results reveal that during the examined period, a notable spatial growth and thickening of the forest areas was found (10,51%) in the pilot area of Kastoria. The spatial homogeneity of the forested areas in Kastoria decreased only by 2,11%. Regarding Propontida, the forested areas decreased in total about 13,02% while the agricultural and arable land has increased by 12,10%.


2003 ◽  
Vol 69 (9) ◽  
pp. 963-972 ◽  
Author(s):  
Nancy Thomas ◽  
Chad Hendrix ◽  
Russell G. Congalton

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243079
Author(s):  
Raquel Fernandes Araujo ◽  
Jeffrey Q. Chambers ◽  
Carlos Henrique Souza Celes ◽  
Helene C. Muller-Landau ◽  
Ana Paula Ferreira dos Santos ◽  
...  

Tree growth and survival differ strongly between canopy trees (those directly exposed to overhead light), and understory trees. However, the structural complexity of many tropical forests makes it difficult to determine canopy positions. The integration of remote sensing and ground-based data enables this determination and measurements of how canopy and understory trees differ in structure and dynamics. Here we analyzed 2 cm resolution RGB imagery collected by a Remotely Piloted Aircraft System (RPAS), also known as drone, together with two decades of bi-annual tree censuses for 2 ha of old growth forest in the Central Amazon. We delineated all crowns visible in the imagery and linked each crown to a tagged stem through field work. Canopy trees constituted 40% of the 1244 inventoried trees with diameter at breast height (DBH) > 10 cm, and accounted for ~70% of aboveground carbon stocks and wood productivity. The probability of being in the canopy increased logistically with tree diameter, passing through 50% at 23.5 cm DBH. Diameter growth was on average twice as large in canopy trees as in understory trees. Growth rates were unrelated to diameter in canopy trees and positively related to diameter in understory trees, consistent with the idea that light availability increases with diameter in the understory but not the canopy. The whole stand size distribution was best fit by a Weibull distribution, whereas the separate size distributions of understory trees or canopy trees > 25 cm DBH were equally well fit by exponential and Weibull distributions, consistent with mechanistic forest models. The identification and field mapping of crowns seen in a high resolution orthomosaic revealed new patterns in the structure and dynamics of trees of canopy vs. understory at this site, demonstrating the value of traditional tree censuses with drone remote sensing.


Author(s):  
Alwyn Kaye

Abstract A set of Heavy Vacuum Gas Oil (HVGO) pumps in a 300 kbbl/day operating Upgrader Plant experienced repeated failures; typically less than 7 weeks. The pumps run continuously in a high-pressure, high temperature and corrosive environment and their functional status directly affects the reliability of the plant. Upon research, an experimental strain measurement technique using very high resolution laser digital imagery and optical metrology was found from military and advanced aerospace applications to verify high level dimensional accuracy of critical components [1]. Application to a complex and operating bitumen upgrader was unknown. The objective of this project was to use advanced optical metrology with digital image processing techniques employing multiple laser and high-speed cameras capable of generating pump and pipe component’s real time strain images, displacement and rate of change. Optical metrology can analyze the mechanical properties and behavior of many materials and in various test scenarios [2]. Hot and cold operating service, with variations in flow and temperature all dynamically affect the strain measurements. Three significant advantages of the optical method are: i. Avoids a host of problems of strain gauge application, wiring and setup. ii. The problems of temperature sensitivity and correction are overcome. [3] iii. Gathers much more extensive data than possible with traditional methods. The vibration characteristics of the pumps and related hardware were analyzed using high resolution laser and photogrammetric digital imagery and digital strain mapping analysis to determine the characteristics that would ensure the long-term reliable and safe operation of the HVGO pumps. The stress and deformation analysis were performed on the operating pumps in a variety of normal (1280 m3/hr.) and upset operating conditions including under partial and full load conditions. Dynamic and modal analysis of the pumps was developed and analyzed. The displacement and tensor fields of the hardware including the pumps, bases and piping were measured using high resolution laser cameras and analyzed. From the high-speed data gathering and loading analysis showed the deformation and stress affecting the pump and related hardware. The key variables undermining reliable performance were revealed and from the data the necessary remedial action was determined. The pumps have operated for over 30months to the time of writing without repeat failure. This paper should be read in conjunction with PVP 2020-21203; Investigation and Resolution of the Fluid Structure Interaction of High Rate HVGO Pumps.


Shore & Beach ◽  
2020 ◽  
pp. 46-52

In recent years, the technology and regulation surrounding the use of unmanned aircraft systems (UASs) has rapidly advanced. This has resulted in the availability of such technology for more common applications. Here we compare manned versus UAS platforms for acquiring high-resolution imagery of subaquatic habitat for the purpose of boat propeller scar delineation in seagrass meadows in Redfish Bay, Texas. We acquired aerial seagrass imagery in three 20-hectare plots using two UASs and one manned aircraft platform. The three plots represented a priori designations of low, moderate, and high seagrass scarring intensity. Overall, we observed that a smaller amount of scarring was detected in the manned aircraft imagery compared to that collected by the two UAS platforms, and that this disparity was much greater for the high scarring intensity plot. The observed differences in scar feature delineations were at least partially related to logistical difference between these two platforms — specifically, the lower altitude flown by the UASs results in a higher spatial resolution of the imagery that is less dependent on the camera specifications. From a logistical standpoint, the potential gain in spatial resolution via lower altitude flight could result in a reduced pricetag for high-resolution mapped products. Further, the rapid deployment and local operation typically resulting from the accessibility of UAS training greatly simplify the logistics of planning imagery acquisition at the appropriate scale. However, we realize that the current trade-off with regard to higher altitude is the ability to cover large areas with fewer transects and shorter flight time. Coverage limitations for UASs is currently rooted in both technological and legal issues. However, as technology and regulations evolve, the technical and logistical comparison of imagery products from UAS and manned platforms will become increasingly important to natural resource managers and researchers looking to make this transition to UAS.


Author(s):  
Stephen Hughes ◽  
Michael Lewis

Attention direction is particularly difficult in open scenes such as detailed aerial photographs, wide angle/multiple video feeds, or high-resolution digital imagery. Unlike conventional displays that have single parameters with definable set points, open scenes lack easy criteria for directing attention. The present study investigates the effects of varying levels of highlighting for correctly and incorrectly designated targets. The results suggest that linking the intensity of highlighting to degree of confidence may be an effective display strategy to maximize efforts to draw attention to objects in an open scene.


2007 ◽  
Vol 8 (6) ◽  
pp. 311-321 ◽  
Author(s):  
C. L. Walthall ◽  
Y. Pachepsky ◽  
W. P. Dulaney ◽  
D. J. Timlin ◽  
C. S. T. Daughtry

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