Mapping the Delivery of Ecological Functions Combining Field Collected Data and Unmanned Aerial Vehicles (UAVs)

Ecosystems - Mapping ecosystem functions and services has gained considerable importance, particularly for its applications in ecosystem management and conservation. While practices for terrestrial...     

Autonomous Navigation for Unmanned Aerial Vehicles Based on Chaotic Bionics Theory

In this paper a new reactive mechanism based on perception-action bionics for multi-sensory integration applied to Un-manned Aerial Vehicles (UAVs) navigation is proposed.The strategy is inspired by the olfactory bulb neural activity observed inrabbits subject to external stimuli.The new UAV navigation technique exploits the use of a multiscroll chaotic system which isable to be controlled in real-time towards less complex orbits,like periodic orbits or equilibrium points,considered as perceptiveorbits.These are subject to real-time modifications on the basis of environment changes acquired through a Synthetic ApertureRadar (SAR) sensory system.The mathematical details of the approach are given including simulation results in a virtual en-vironment.The results demonstrate the capability of autonomous navigation for UAV based on chaotic bionics theory in com-plex spatial environments.     

Development of a PWM Precision Spraying Controller for Unmanned Aerial Vehicles

This paper presents a new Pulse Width Modulation (PWM) controller for Unmanned Aerial Vehicle (UAV) precisionsprayer for agriculture using a TL494 fixed-frequency pulse width modulator together with a data acquisition board and developedsoftware. An UAV can be remotely controlled or flown autonomously by pre-programmed flight plans. The PWMcontroller was implemented through the guidance system on the UAV with control commands sent between the UAV helicopterand the ground control station via a wireless telemetry system. The PWM controller was tested and validated using LabVIEW8.2. Several analyses were performed in a laboratory to test different control signals. The results show that the PWM controllerhas promise as a higher precision technique for spray applications, which will improve efficiency of pesticide application,especially in crop production areas.     

Reconstructing historical baselines for the Persian/Arabian Gulf Dugong,Dugong dugon (Mammalia: Sirena)

Retrospective estimates of historic abundances and distributions of marine organisms are crucial to understanding the anthropogenic impacts on the structure and species of coastal ecosystems, especially in the case of vulnerable species such as the Dugong (Dugong dugon). The Persian/Arabian Gulf is home to the second largest Dugong population in the world, yet little is known about their current or past abundance, distribution, and ecological role. Here, we examine historical changes in dugong distribution and estimate perceived changes in their abundance. We create a ‘dugong discovery curve’ and compile global density estimates as proxies for the overall health of the population in the Gulf. We find that since 1950 dugong range may have contracted by one quarter, and despite their large population, their overall densities in the Gulf are far lower than in other areas within their range. Basic understanding of historical trajectories for Dugongs is needed in order to develop appropriate management plans and conservation targets, particularly in light of large and wide-spread coastal development projects in the region.     

Configuration and Specifications of an Unmanned Aerial Vehicle (UAV) for Early Site Specific Weed Management

A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were also evaluated. Two different sensors, a still visible camera and a six-band multispectral camera, and three flight altitudes (30, 60 and 100 m) were tested over a naturally infested sunflower field. The main phases of the UAV workflow were the following: 1) mission planning, 2) UAV flight and image acquisition, and 3) image pre-processing. Three different aspects were needed to plan the route: flight area, camera specifications and UAV tasks. The pre-processing phase included the correct alignment of the six bands of the multispectral imagery and the orthorectification and mosaicking of the individual images captured in each flight. The image pixel size, area covered by each image and flight timing were very sensitive to flight altitude. At a lower altitude, the UAV captured images of finer spatial resolution, although the number of images needed to cover the whole field may be a limiting factor due to the energy required for a greater flight length and computational requirements for the further mosaicking process. Spectral differences between weeds, crop and bare soil were significant in the vegetation indices studied (Excess Green Index, Normalised Green-Red Difference Index and Normalised Difference Vegetation Index), mainly at a 30 m altitude. However, greater spectral separability was obtained between vegetation and bare soil with the index NDVI. These results suggest that an agreement among spectral and spatial resolutions is needed to optimise the flight mission according to every agronomical objective as affected by the size of the smaller object to be discriminated (weed plants or weed patches).     

High-Throughput 3-D Monitoring of Agricultural-Tree Plantations with Unmanned Aerial Vehicle (UAV) Technology

The geometric features of agricultural trees such as canopy area, tree height and crown volume provide useful information about plantation status and crop production. However, these variables are mostly estimated after a time-consuming and hard field work and applying equations that treat the trees as geometric solids, which produce inconsistent results. As an alternative, this work presents an innovative procedure for computing the 3-dimensional geometric features of individual trees and tree-rows by applying two consecutive phases: 1) generation of Digital Surface Models with Unmanned Aerial Vehicle (UAV) technology and 2) use of object-based image analysis techniques. Our UAV-based procedure produced successful results both in single-tree and in tree-row plantations, reporting up to 97% accuracy on area quantification and minimal deviations compared to in-field estimations of tree heights and crown volumes. The maps generated could be used to understand the linkages between tree grown and field-related factors or to optimize crop management operations in the context of precision agriculture with relevant agro-environmental implications.     

Oil palm trees detection and counting on Microsoft Bing Maps Very High Resolution (VHR) satellite imagery and Unmanned Aerial Vehicles (UAV) data using image processing thresholding approach

Palm oil is one of the highest producing vegetable oil crops globally, with production increasing rapidly over the last 40 years from 5 million tonnes in 1980 to 74.5 million tonnes in 2019. This increase in production is in line with the high demand for vegetable oils worldwide. The accurate monitoring and statistics of oil palm plantation data are essential to support effective and efficient decision-making. However, the most commonly adopted data collection still uses conventional methods, i.e., field surveys, which are highly dependent on the massive amount of human resources, cost, processing time, and difficulty reaching remote areas. Remote sensing using satellite and UAV imagery can be an alternative in data collection due to its distinct advantages with a more efficient labor force, affordable cost, shorter time updates, and covering areas that are difficult to reach. In this work, we investigate the utilization of remote sensing data from Microsoft Bing Maps Very High Resolution (VHR) satellite imagery and Unmanned Aerial Vehicle (UAV) data using the image processing thresholding method for detecting and counting oil palm trees. The combination of Hue, Saturation, and Value (HSV) conversion, the Otsu segmentation thresholding, and contours detection and counting methods are used in our approach to enhance the accuracy of captured features of oil palm trees. The detection results are further categorized into best-case, average-case, and worst-case detection to comprehend the challenging real-world situation, based on the quality of captured imageries and model prediction results. Our proposed approach achieves better and more promising results when using UAV image data. This is indicated by an average true-positive rate (TPR) of 88 to 97% in best-case data input, 70 to 81% in average-case data input, 30 to 53% in worst-case data input, and 10% in estimation error. Meanwhile, Bing image data provides an average true-positive rate (TPR) of 9 to 13% in the best-case data input, 5 to 6% in the average-case data input, and 1 to 3% in the worst-case data input, with an average estimation error up to 78%. Overall, our proposed approach can perform the oil palm trees detection and counting. We also suggest that higher resolution imagery than Microsoft Bing maps or single utilization of UAV data can be considered input for better results. Our study could further be beneficial in providing more scalable and accurate plantation statistics.     

A PCR assay for gender assignment in dugong (Dugong dugon) and West Indian manatee (Trichechus manatus)

Gender assignment for some aquatic mammals in the field is difficult. Molecular sexing from tissue biopsies is possible as males are heterogametic. Here we describe a multiplex PCR assay that amplifies the male specific SRY gene and differentiates ZFX and ZFY gametologues in two sirenian species, dugong (Dugong dugon) and West Indian manatee (Trichechus manatus). The assay was validated with animals of known gender and proved accurate and robust to experimental failure.     

A Linear Domain System Identification for Small Unmanned Aerial Rotorcraft Based on Adaptive Genetic Algorithm

<正> This paper proposes a new adaptive linear domain system identification method for small unmanned aerial rotorcraft.Byusing the flash memory integrated into the micro guide navigation control module, system records the data sequences of flighttests as inputs (control signals for servos) and outputs (aircraft's attitude and velocity information).After data preprocessing, thesystem constructs the horizontal and vertical dynamic model for the small unmanned aerial rotorcraft using adaptive geneticalgorithm.The identified model is verified by a series of simulations and tests.Comparison between flight data and the one-stepprediction data obtained from the identification model shows that the dynamic model has a good estimation for real unmannedaerial rotorcraft system.Based on the proposed dynamic model, the small unmanned aerial rotorcraft can perform hovering,turning, and straight flight tasks in real flight tests.     

Weed Mapping in Early-Season Maize Fields Using Object-Based Analysis of Unmanned Aerial Vehicle (UAV) Images

The use of remote imagery captured by unmanned aerial vehicles (UAV) has tremendous potential for designing detailed site-specific weed control treatments in early post-emergence, which have not possible previously with conventional airborne or satellite images. A robust and entirely automatic object-based image analysis (OBIA) procedure was developed on a series of UAV images using a six-band multispectral camera (visible and near-infrared range) with the ultimate objective of generating a weed map in an experimental maize field in Spain. The OBIA procedure combines several contextual, hierarchical and object-based features and consists of three consecutive phases: 1) classification of crop rows by application of a dynamic and auto-adaptive classification approach, 2) discrimination of crops and weeds on the basis of their relative positions with reference to the crop rows, and 3) generation of a weed infestation map in a grid structure. The estimation of weed coverage from the image analysis yielded satisfactory results. The relationship of estimated versus observed weed densities had a coefficient of determination of r²=0.89 and a root mean square error of 0.02. A map of three categories of weed coverage was produced with 86% of overall accuracy. In the experimental field, the area free of weeds was 23%, and the area with low weed coverage (<5% weeds) was 47%, which indicated a high potential for reducing herbicide application or other weed operations. The OBIA procedure computes multiple data and statistics derived from the classification outputs, which permits calculation of herbicide requirements and estimation of the overall cost of weed management operations in advance.     

越南蜘蛛区系的初步研究(蛛形纲:蜘蛛目)

依据镜检标本和已知文献, 初步研究了越南的蜘蛛区系。包括本文报道的 21 种新记录在内, 越南蜘蛛目前已知 320 种及 1 亚种。     

宁夏粉蚧科昆虫研究（半翅目：蚧总科）

记述宁夏同族自治区粉蚧科Pseudococcidae昆虫24属41种,其中包括2新种:宁夏草粉蚧Fonscolombia ningxiana,sp.nov.和冰草长粉蚧Longicoccus agropyri.sp.nov.;2中国新记录种:多管刺粉蚧spinococcus multitubulatus(Danzig,1980)和孤独条粉蚧Trionymus singularis Schmutterer,1952:1新组合:赖草长粉蚧Longicoccus leymicola(Tang,1992),comb.n.(移自少粉蚧属Mirococcus Borchsenius);Puto jarudensis Tang(1992)为Ceroputopilosellae Sulc.1898的新异名.模式标本保存在山西农业大学蚧虫研究中心.     

A Diverse Ant Fauna from the Mid-Cretaceous of Myanmar (Hymenoptera: Formicidae)

A new collection of 24 wingless ant specimens from mid-Cretaceous Burmese amber (Albian-Cenomanian, 99 Ma) comprises nine new species belonging to the genus Sphecomyrmodes Engel and Grimaldi. Described taxa vary considerably with regard to total size, head and body proportion, cuticular sculpturing, and petiole structure while all species are unified by a distinct shared character. The assemblage represents the largest known diversification of closely related Cretaceous ants with respect to species number. These stem-group ants exhibit some characteristics previously known only from their extant counterparts along with presumed plesiomorphic morphology. Consequently, their morphology may inform hypotheses relating to basal relationships and general patterns of ant evolution. These and other uncovered Cretaceous species indicate that stem-group ants are not simply wasp-like, transitional formicids, but rather a group of considerable adaptive diversity, exhibiting innovations analogous to what crown-group ants would echo 100 million years later.     

An Ecological Study of the Fauna Inhabiting the Sublittoral Marine Alga Saccorhiza polyschides (Lightf.) Batt.

Summary The animals found on the fronds of the laminarian alga Saccorhiza polyschides are described. The sporophytes supported a fauna which was distinct from that of the surrounding rock, but was basically similar to that of other laminarian algae. Several animal species were however, much more abundant on S. polyschides than on other laminarians. A number of species were found to have a localised distribution on the host plant. The distribution of the epifauna on the alga seems to be chiefly the result of factors in the external environment particularly the degree of water movement and of silting. The epifauna varied in abundance and composition at different sites. In localities exposed to excessive water turbulence only a few species survived, although the gastropods Patina pellucida and Lacuna vincta were at their most abundant in such localities. Marked seasonal variations in the composition of the epifauna were found at Port Erin, Isle of Man, over a period of two years. The variations were related to both the seasonal behaviour of the animal species and to the annual cycle of growth and decay exhibited by the host plant. It is clear that the plant and its epifauna are each an important factor in the ecology of the other.

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Zusammenfassung Die Tiere, die auf den Wedeln der Laminaria-Alge Saccorhiza polyschides gefunden wurden, werden beschrieben. Die Sporophyten ern?hrten eine Fauna, die sich von der auf dem benachbarten Gestein unterschied, aber im Grunde der anderer Laminaria-Algen ahnelte. Verschiedene Tierarten waren jedoch viel zahlreicher auf S. polyschides als auf anderen Laminaria. Eine Reihe von Arten fanden sich an einzelnen Stellen auf dem Wirt. Die Verbreitung der Epifauna auf der Alge scheint in erster Linie das Ergebnis von Faktoren der Umwelt zu sein, v.a. des Grades der Wasserbewegung und der Verschlammung. Die Epifauna ver?nderte sich in Fülle and Zusammensetzung an verschiedenen Stellen. In Lokalitaten, die ausserordentlicher Wasserturbulenz ausgesetzt waren, überlebten nur ein paar Arten, obwohl die Gastropoden Patina pellucida und Lacuna vincta in solchen Lokalit?ten am h?ufigsten vorkamen. Deutliche jahreszeitliche Ver?nderungen in der Zusammensetzung der Epifauna fanden sich in Port Erin, auf der Insel Man, über einen Zeitraum von zwei Jahren. Die Ver?nderungen standen im Zusammenhang mit dem jahreszeitlichen Verhalten der Tierarten und dem Jahreszyklus von Wachstum and Zerfall, der von der Wirtpflanze gezeigt wird. Es ist klar, dass die Pflanze and ihre Epifauna beide einen wichtigen Faktor in der ?kologie der Anderen darstellen.

     

Pond Smelt Hypomesus olidus (Osmeridae): A New Species for the Fauna of the Barents Sea

Journal of Ichthyology - Data on the record of a large population of pond smelt Hypomesus olidus in the southeastern Barents Sea, outside the generally accepted boundaries of the natural range...     

Remodeling Marine Tenure on the Atolls: A Case Study from Western Kiribati, Micronesia

Kiribati underwent dramatic changes in laws governing access to intertidal resources as a result of colonial intrusion. In recent years, the impact of population growth, urbanization, more efficient extractive technologies, and expanding market opportunities have prompted island councils to adopt by-laws to protect existing resources. However, there remains the challenge of enforcing territorial rights. Several approaches that might lead to a viable tenurial system include alternative short-term gains, cooperative ventures, and the judicious application of TEK (Traditional Ecological Knowledge) as an instrument for resource management. The first two are seen as preconditions for the success of the third because of the insights they provide within the context of behavioral ecology. This theoretical approach and associated models caution us from essentializing the environmental outcomes of human behavior by showing the lack of a resource conservation strategy. These aforementioned solutions for ensuring sustainable development of the intertidal zone are discussed based on fieldwork among several atoll communities in Western Kiribati with a focus on shellfish gathering.     

Cost and Precision Functions for Aerial Quadrat Surveys: a Case Study of Ring-Necked Ducks in Minnesota

ABSTRACT Cost considerations may be as important as precision when making survey-design choices, and the ability to accurately estimate survey costs will be essential if survey budgets become more constrained. We used data from a survey of ring-necked ducks (Aythya collaris) to illustrate how simple distance formulas can be used to construct a cost function for aerial quadrat surveys. Our cost function provided reasonable estimates of effort (hr) and costs, and allowed us to evaluate plot-size choices in terms of expected cost-precision tradeoffs. Although factors influencing costs in wildlife surveys can be complicated, we believe that cost functions deserve more attention and should be routinely considered in conjunction with traditional power analyses.     

Heterozygous Mapping Strategy (HetMappS) for High Resolution Genotyping-By-Sequencing Markers: A Case Study in Grapevine

Genotyping by sequencing (GBS) provides opportunities to generate high-resolution genetic maps at a low genotyping cost, but for highly heterozygous species, missing data and heterozygote undercalling complicate the creation of GBS genetic maps. To overcome these issues, we developed a publicly available, modular approach called HetMappS, which functions independently of parental genotypes and corrects for genotyping errors associated with heterozygosity. For linkage group formation, HetMappS includes both a reference-guided synteny pipeline and a reference-independent de novo pipeline. The de novo pipeline can be utilized for under-characterized or high diversity families that lack an appropriate reference. We applied both HetMappS pipelines in five half-sib F₁ families involving genetically diverse Vitis spp. Starting with at least 116,466 putative SNPs per family, the HetMappS pipelines identified 10,440 to 17,267 phased pseudo-testcross (Pt) markers and generated high-confidence maps. Pt marker density exceeded crossover resolution in all cases; up to 5,560 non-redundant markers were used to generate parental maps ranging from 1,047 cM to 1,696 cM. The number of markers used was strongly correlated with family size in both de novo and synteny maps (r = 0.92 and 0.91, respectively). Comparisons between allele and tag frequencies suggested that many markers were in tandem repeats and mapped as single loci, while markers in regions of more than two repeats were removed during map curation. Both pipelines generated similar genetic maps, and genetic order was strongly correlated with the reference genome physical order in all cases. Independently created genetic maps from shared parents exhibited nearly identical results. Flower sex was mapped in three families and correctly localized to the known sex locus in all cases. The HetMappS pipeline could have wide application for genetic mapping in highly heterozygous species, and its modularity provides opportunities to adapt portions of the pipeline to other family types, genotyping technologies or applications.     

Population structure of Lankatrematoides gardneri (Digenea: Opisthotrematidae) in the pancreas of the dugong (Dugong dugon) (Mammalia: Sirenia).

The distribution among size and reproductive classes of the digenean Lankatrematoides gardneri was recorded from the pancreatic ducts of 41 dugongs from the Gulf of Papua, Papua New Guinea. Infrapopulation sizes ranged from 5 to 921 worms and showed no correlation with host age, sex, or month of capture. Immature worms tended to be concentrated in intermediate size classes, the largest immatures being no more numerous than matures. The mean proportion of mature worms in the 29 infrapopulations containing them was small (9.8%). Mature worms were significantly greater in mass than the largest immatures. There is evidence of an interaction between the presence or absence of mature worms and the distribution of immatures among classes.