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134-472: The vision for NEON is to guide global understanding and decisions in a changing environment with scientific information about continental-scale ecology through integrated observations, experiments and forecasts. NEON's mission is to design, implement and operate the first and foremost integrated continental‐scale scientific infrastructure to enable research, discovery and education about ecological change. NEON collects ecological and climatic observations across

268-417: A time-of-flight camera is used to collect information about both the 3-D location and intensity of the light incident on it in every frame. However, in scanning lidar, this camera contains only a point sensor, while in flash lidar, the camera contains either a 1-D or a 2-D sensor array , each pixel of which collects 3-D location and intensity information. In both cases, the depth information is collected using

402-399: A combination with a polygon mirror, and a dual axis scanner . Optic choices affect the angular resolution and range that can be detected. A hole mirror or a beam splitter are options to collect a return signal. Two main photodetector technologies are used in lidar: solid state photodetectors, such as silicon avalanche photodiodes , or photomultipliers . The sensitivity of the receiver

536-492: A continental-scale observatory, and it identified the following Environmental Grand Challenges: Thus, the data and observations that NEON collects focuses on how land use, climate change and invasive species affect biodiversity, disease ecology , and ecosystem services . Obtaining integrated data on these relationships over a long-term period is crucial to improving forecast models and resource management for environmental change. The National Science Foundation's vision for NEON

670-423: A different principle described in a Flash Lidar below. Microelectromechanical mirrors (MEMS) are not entirely solid-state. However, their tiny form factor provides many of the same cost benefits. A single laser is directed to a single mirror that can be reoriented to view any part of the target field. The mirror spins at a rapid rate. However, MEMS systems generally operate in a single plane (left to right). To add

804-738: A distance requires a powerful burst of light. The power is limited to levels that do not damage human retinas. Wavelengths must not affect human eyes. However, low-cost silicon imagers do not read light in the eye-safe spectrum. Instead, gallium-arsenide imagers are required, which can boost costs to $ 200,000. Gallium-arsenide is the same compound used to produce high-cost, high-efficiency solar panels usually used in space applications. Lidar can be oriented to nadir , zenith , or laterally. For example, lidar altimeters look down, an atmospheric lidar looks up, and lidar-based collision avoidance systems are side-looking. Laser projections of lidars can be manipulated using various methods and mechanisms to produce

938-465: A dramatic effect on community structure. Hunting of sea otters, for example, is thought to have led indirectly to the extinction of the Steller's sea cow ( Hydrodamalis gigas ). While the keystone species concept has been used extensively as a conservation tool, it has been criticized for being poorly defined from an operational stance. It is difficult to experimentally determine what species may hold

1072-428: A dramatic impact on the ecology of individual species or whole ecosystems. For instance, the replacement of an ant species by another (invasive) ant species has been shown to affect how elephants reduce tree cover and thus the predation of lions on zebras . A trophic level (from Greek troph , τροφή, trophē, meaning "food" or "feeding") is "a group of organisms acquiring a considerable majority of its energy from

1206-416: A few peak returns, while more recent systems acquire and digitize the entire reflected signal. Scientists analysed the waveform signal for extracting peak returns using Gaussian decomposition . Zhuang et al, 2017 used this approach for estimating aboveground biomass. Handling the huge amounts of full-waveform data is difficult. Therefore, Gaussian decomposition of the waveforms is effective, since it reduces

1340-412: A flattened body relative to the main populations that live in open savanna. The population that lives in an isolated rock outcrop hides in crevasses where its flattened body offers a selective advantage. Habitat shifts also occur in the developmental life history of amphibians, and in insects that transition from aquatic to terrestrial habitats. Biotope and habitat are sometimes used interchangeably, but

1474-550: A green spectrum (532 nm) laser beam. Two beams are projected onto a fast rotating mirror, which creates an array of points. One of the beams penetrates the water and also detects the bottom surface of the water under favorable conditions. Water depth measurable by lidar depends on the clarity of the water and the absorption of the wavelength used. Water is most transparent to green and blue light, so these will penetrate deepest in clean water. Blue-green light of 532 nm produced by frequency doubled solid-state IR laser output

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1608-612: A higher one." Small scale patterns do not necessarily explain large scale phenomena, otherwise captured in the expression (coined by Aristotle) 'the sum is greater than the parts'. "Complexity in ecology is of at least six distinct types: spatial, temporal, structural, process, behavioral, and geometric." From these principles, ecologists have identified emergent and self-organizing phenomena that operate at different environmental scales of influence, ranging from molecular to planetary, and these require different explanations at each integrative level . Ecological complexity relates to

1742-444: A keystone role in each ecosystem. Furthermore, food web theory suggests that keystone species may not be common, so it is unclear how generally the keystone species model can be applied. Complexity is understood as a large computational effort needed to piece together numerous interacting parts exceeding the iterative memory capacity of the human mind. Global patterns of biological diversity are complex. This biocomplexity stems from

1876-408: A keystone species can result in a community collapse just as the removal of the keystone in an arch can result in the arch's loss of stability. Sea otters ( Enhydra lutris ) are commonly cited as an example of a keystone species because they limit the density of sea urchins that feed on kelp . If sea otters are removed from the system, the urchins graze until the kelp beds disappear, and this has

2010-741: A legacy niche that was constructed before their time. Biomes are larger units of organization that categorize regions of the Earth's ecosystems, mainly according to the structure and composition of vegetation. There are different methods to define the continental boundaries of biomes dominated by different functional types of vegetative communities that are limited in distribution by climate, precipitation, weather, and other environmental variables. Biomes include tropical rainforest , temperate broadleaf and mixed forest , temperate deciduous forest , taiga , tundra , hot desert , and polar desert . Other researchers have recently categorized other biomes, such as

2144-439: A linear successional route, changes might occur quickly or slowly over thousands of years before specific forest successional stages are brought about by biological processes. An ecosystem's area can vary greatly, from tiny to vast. A single tree is of little consequence to the classification of a forest ecosystem, but is critically relevant to organisms living in and on it. Several generations of an aphid population can exist over

2278-439: A macroscopic view of the system. While the notion of trophic levels provides insight into energy flow and top-down control within food webs, it is troubled by the prevalence of omnivory in real ecosystems. This has led some ecologists to "reiterate that the notion that species clearly aggregate into discrete, homogeneous trophic levels is fiction." Nonetheless, recent studies have shown that real trophic levels do exist, but "above

2412-410: A microscopic array of individual antennas. Controlling the timing (phase) of each antenna steers a cohesive signal in a specific direction. Phased arrays have been used in radar since the 1940s. On the order of a million optical antennas are used to see a radiation pattern of a certain size in a certain direction. To achieve this the phase of each individual antenna (emitter) are precisely controlled. It

2546-516: A mix of herbivores and predators). Omnivores do not fit neatly into a functional category because they eat both plant and animal tissues. It has been suggested that omnivores have a greater functional influence as predators because compared to herbivores, they are relatively inefficient at grazing. Trophic levels are part of the holistic or complex systems view of ecosystems. Each trophic level contains unrelated species that are grouped together because they share common ecological functions, giving

2680-413: A moving vehicle to collect data along a path. These scanners are almost always paired with other kinds of equipment, including GNSS receivers and IMUs . One example application is surveying streets, where power lines, exact bridge heights, bordering trees, etc. all need to be taken into account. Instead of collecting each of these measurements individually in the field with a tachymeter , a 3-D model from

2814-420: A new appreciation for the influence that organisms have on the ecosystem and evolutionary process. The term "niche construction" is more often used in reference to the under-appreciated feedback mechanisms of natural selection imparting forces on the abiotic niche. An example of natural selection through ecosystem engineering occurs in the nests of social insects , including ants, bees, wasps, and termites. There

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2948-513: A new imaging chip with more than 16,384 pixels, each able to image a single photon, enabling them to capture a wide area in a single image. An earlier generation of the technology with one fourth as many pixels was dispatched by the U.S. military after the January 2010 Haiti earthquake. A single pass by a business jet at 3,000 m (10,000 ft) over Port-au-Prince was able to capture instantaneous snapshots of 600 m (2,000 ft) squares of

3082-431: A point cloud can be created where all of the measurements needed can be made, depending on the quality of the data collected. This eliminates the problem of forgetting to take a measurement, so long as the model is available, reliable and has an appropriate level of accuracy. Terrestrial lidar mapping involves a process of occupancy grid map generation . The process involves an array of cells divided into grids which employ

3216-435: A population-level phenomenon, as with the migration routes followed by plants as they occupied northern post-glacial environments. Plant ecologists use pollen records that accumulate and stratify in wetlands to reconstruct the timing of plant migration and dispersal relative to historic and contemporary climates. These migration routes involved an expansion of the range as plant populations expanded from one area to another. There

3350-407: A process to store the height values when lidar data falls into the respective grid cell. A binary map is then created by applying a particular threshold to the cell values for further processing. The next step is to process the radial distance and z-coordinates from each scan to identify which 3-D points correspond to each of the specified grid cell leading to the process of data formation. There are

3484-401: A region), and sites are classed either as sources or sinks. A site is a generic term that refers to places where ecologists sample populations, such as ponds or defined sampling areas in a forest. Source patches are productive sites that generate a seasonal supply of juveniles that migrate to other patch locations. Sink patches are unproductive sites that only receive migrants; the population at

3618-490: A scanning effect: the standard spindle-type, which spins to give a 360-degree view; solid-state lidar, which has a fixed field of view, but no moving parts, and can use either MEMS or optical phased arrays to steer the beams; and flash lidar, which spreads a flash of light over a large field of view before the signal bounces back to a detector. Lidar applications can be divided into airborne and terrestrial types. The two types require scanners with varying specifications based on

3752-517: A seasonal influx of new immigrants. A dynamic metapopulation structure evolves from year to year, where some patches are sinks in dry years and are sources when conditions are more favorable. Ecologists use a mixture of computer models and field studies to explain metapopulation structure. Community ecology examines how interactions among species and their environment affect the abundance, distribution and diversity of species within communities. Johnson & Stinchcomb (2007) Community ecology

3886-400: A second dimension generally requires a second mirror that moves up and down. Alternatively, another laser can hit the same mirror from another angle. MEMS systems can be disrupted by shock/vibration and may require repeated calibration. Image development speed is affected by the speed at which they are scanned. Options to scan the azimuth and elevation include dual oscillating plane mirrors,

4020-456: A species describes the environment over which a species is known to occur and the type of community that is formed as a result. More specifically, "habitats can be defined as regions in environmental space that are composed of multiple dimensions, each representing a biotic or abiotic environmental variable; that is, any component or characteristic of the environment related directly (e.g. forage biomass and quality) or indirectly (e.g. elevation) to

4154-402: A specific habitat, such as a cave or a pond, and principles gleaned from small-scale studies are extrapolated to larger systems. Feeding relations require extensive investigations, e.g. into the gut contents of organisms, which can be difficult to decipher, or stable isotopes can be used to trace the flow of nutrient diets and energy through a food web. Despite these limitations, food webs remain

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4288-504: A stand-alone word in 1963 suggests that it originated as a portmanteau of " light " and "radar": "Eventually the laser may provide an extremely sensitive detector of particular wavelengths from distant objects. Meanwhile, it is being used to study the Moon by 'lidar' (light radar) ..." The name " photonic radar " is sometimes used to mean visible-spectrum range finding like lidar. Lidar's first applications were in meteorology, for which

4422-446: A valuable tool in understanding community ecosystems. Food webs illustrate important principles of ecology : some species have many weak feeding links (e.g., omnivores ) while some are more specialized with fewer stronger feeding links (e.g., primary predators ). Such linkages explain how ecological communities remain stable over time and eventually can illustrate a "complete" web of life. The disruption of food webs may have

4556-417: A whole functional system, such as an ecosystem , cannot be predicted or understood by a simple summation of the parts. "New properties emerge because the components interact, not because the basic nature of the components is changed." LiDAR Lidar ( / ˈ l aɪ d ɑːr / , also LIDAR , LiDAR or LADAR , an acronym of "light detection and ranging" or "laser imaging, detection, and ranging" )

4690-399: A wide array of interacting levels of organization spanning micro-level (e.g., cells ) to a planetary scale (e.g., biosphere ) phenomena . Ecosystems, for example, contain abiotic resources and interacting life forms (i.e., individual organisms that aggregate into populations which aggregate into distinct ecological communities). Because ecosystems are dynamic and do not necessarily follow

4824-440: A wide range of materials, including non-metallic objects, rocks, rain, chemical compounds, aerosols , clouds and even single molecules . A narrow laser beam can map physical features with very high resolutions ; for example, an aircraft can map terrain at 30-centimetre (12 in) resolution or better. The essential concept of lidar was originated by E. H. Synge in 1930, who envisaged the use of powerful searchlights to probe

4958-544: A wide variety of lidar applications, in addition to the applications listed below, as it is often mentioned in National lidar dataset programs. These applications are largely determined by the range of effective object detection; resolution, which is how accurately the lidar identifies and classifies objects; and reflectance confusion, meaning how well the lidar can see something in the presence of bright objects, like reflective signs or bright sun. Companies are working to cut

5092-584: Is a case study that used the voxelisation approach for detecting dead standing Eucalypt trees in Australia. Terrestrial applications of lidar (also terrestrial laser scanning ) happen on the Earth's surface and can be either stationary or mobile. Stationary terrestrial scanning is most common as a survey method, for example in conventional topography, monitoring, cultural heritage documentation and forensics. The 3-D point clouds acquired from these types of scanners can be matched with digital images taken of

5226-485: Is a central concept in the ecology of organisms and is sub-divided into the fundamental and the realized niche. The fundamental niche is the set of environmental conditions under which a species is able to persist. The realized niche is the set of environmental plus ecological conditions under which a species persists. The Hutchinsonian niche is defined more technically as a " Euclidean hyperspace whose dimensions are defined as environmental variables and whose size

5360-504: Is a function of the number of values that the environmental values may assume for which an organism has positive fitness ." Biogeographical patterns and range distributions are explained or predicted through knowledge of a species' traits and niche requirements. Species have functional traits that are uniquely adapted to the ecological niche. A trait is a measurable property, phenotype , or characteristic of an organism that may influence its survival. Genes play an important role in

5494-414: Is a larger taxonomy of movement, such as commuting, foraging, territorial behavior, stasis, and ranging. Dispersal is usually distinguished from migration because it involves the one-way permanent movement of individuals from their birth population into another population. In metapopulation terminology, migrating individuals are classed as emigrants (when they leave a region) or immigrants (when they enter

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5628-454: Is a method for determining ranges by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. Lidar may operate in a fixed direction (e.g., vertical) or it may scan multiple directions, in which case it is known as lidar scanning or 3D laser scanning , a special combination of 3-D scanning and laser scanning . Lidar has terrestrial, airborne, and mobile applications. Lidar

5762-461: Is an emergent homeostasis or homeorhesis in the structure of the nest that regulates, maintains and defends the physiology of the entire colony. Termite mounds, for example, maintain a constant internal temperature through the design of air-conditioning chimneys. The structure of the nests themselves is subject to the forces of natural selection. Moreover, a nest can survive over successive generations, so that progeny inherit both genetic material and

5896-447: Is another parameter that has to be balanced in a lidar design. Lidar sensors mounted on mobile platforms such as airplanes or satellites require instrumentation to determine the absolute position and orientation of the sensor. Such devices generally include a Global Positioning System receiver and an inertial measurement unit (IMU). Lidar uses active sensors that supply their own illumination source. The energy source hits objects and

6030-404: Is another statistical approach that is often used in conservation research . Metapopulation models simplify the landscape into patches of varying levels of quality, and metapopulations are linked by the migratory behaviours of organisms. Animal migration is set apart from other kinds of movement because it involves the seasonal departure and return of individuals from a habitat. Migration is also

6164-438: Is commonly used to make high-resolution maps, with applications in surveying , geodesy , geomatics , archaeology , geography , geology , geomorphology , seismology , forestry , atmospheric physics , laser guidance , airborne laser swathe mapping (ALSM), and laser altimetry . It is used to make digital 3-D representations of areas on the Earth's surface and ocean bottom of the intertidal and near coastal zone by varying

6298-904: Is described as: "A continental scale research instrument consisting of geographically distributed infrastructure, networked via state-of-the-art communications. Cutting-edge lab and field instrumentation, site-based experimental infrastructure, natural history archive facilities and/or computational, analytical and modeling capabilities, linked via a computational network will comprise NEON. NEON will transform ecological research by enabling studies on major environmental challenges at regional to continental scales. Scientists and engineers will use NEON to conduct real-time ecological studies spanning all levels of biological organization and temporal and geographical scales. NSF disciplinary and multi-disciplinary programs will support NEON research projects and educational activities. Data from standard measurements made using NEON will be publicly available.” (NSF 04549, 2004) NEON

6432-460: Is for the green laser light to penetrate water about one and a half to two times Secchi depth in Indonesian waters. Water temperature and salinity have an effect on the refractive index which has a small effect on the depth calculation. The data obtained shows the full extent of the land surface exposed above the sea floor. This technique is extremely useful as it will play an important role in

6566-438: Is greater than respiration) by photosynthesis or chemosynthesis . Heterotrophs are organisms that must feed on others for nourishment and energy (respiration exceeds production). Heterotrophs can be further sub-divided into different functional groups, including primary consumers (strict herbivores), secondary consumers ( carnivorous predators that feed exclusively on herbivores), and tertiary consumers (predators that feed on

6700-418: Is not visible in night vision goggles , unlike the shorter 1,000 nm infrared laser. Airborne topographic mapping lidars generally use 1,064 nm diode-pumped YAG lasers, while bathymetric (underwater depth research) systems generally use 532 nm frequency-doubled diode pumped YAG lasers because 532 nm penetrates water with much less attenuation than 1,064 nm. Laser settings include

6834-684: Is outfitted with soil sensor arrays and a tower mounted with sensory equipment. Towers are built to extend above the vegetation canopy and take measurements such as on air quality, carbon dioxide flux, temperature, and atmospheric pressure. Additional sampling plots are located within the airshed of the tower. Sites are organized within 20 separate ecoclimatic domains throughout the United States. They are divided by terrestrial and aquatic sampling. Ecology Ecology (from Ancient Greek οἶκος ( oîkos )  'house' and -λογία ( -logía )  'study of')

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6968-448: Is processed using a toolbox called Toolbox for Lidar Data Filtering and Forest Studies (TIFFS) for lidar data filtering and terrain study software. The data is interpolated to digital terrain models using the software. The laser is directed at the region to be mapped and each point's height above the ground is calculated by subtracting the original z-coordinate from the corresponding digital terrain model elevation. Based on this height above

7102-533: Is specifically designed to address central scientific questions about the interactions of ecosystems , climate , and land use: The data and information products that NEON collects and provides is readily available to scientists, educators, students, decision makers and the public to use to understand and address ecological questions and issues. Data is provided as meaningful information and learning tools that engage many audiences, including members of underserved communities, and promote broad ecological literacy. NEON

7236-590: Is the Park Grass Experiment , which was initiated in 1856. Another example is the Hubbard Brook study , which has been in operation since 1960. Holism remains a critical part of the theoretical foundation in contemporary ecological studies. Holism addresses the biological organization of life that self-organizes into layers of emergent whole systems that function according to non-reducible properties. This means that higher-order patterns of

7370-460: Is the natural science of the relationships among living organisms and their environment . Ecology considers organisms at the individual, population , community , ecosystem , and biosphere levels. Ecology overlaps with the closely related sciences of biogeography , evolutionary biology , genetics , ethology , and natural history . Ecology is a branch of biology , and is the study of abundance , biomass , and distribution of organisms in

7504-708: Is the ability to filter out reflections from vegetation from the point cloud model to create a digital terrain model which represents ground surfaces such as rivers, paths, cultural heritage sites, etc., which are concealed by trees. Within the category of airborne lidar, there is sometimes a distinction made between high-altitude and low-altitude applications, but the main difference is a reduction in both accuracy and point density of data acquired at higher altitudes. Airborne lidar can also be used to create bathymetric models in shallow water. The main constituents of airborne lidar include digital elevation models (DEM) and digital surface models (DSM). The points and ground points are

7638-413: Is the biosphere: the total sum of ecosystems on the planet. Ecological relationships regulate the flux of energy, nutrients, and climate all the way up to the planetary scale. For example, the dynamic history of the planetary atmosphere's CO 2 and O 2 composition has been affected by the biogenic flux of gases coming from respiration and photosynthesis, with levels fluctuating over time in relation to

7772-417: Is the standard for airborne bathymetry. This light can penetrate water but pulse strength attenuates exponentially with distance traveled through the water. Lidar can measure depths from about 0.9 to 40 m (3 to 131 ft), with vertical accuracy in the order of 15 cm (6 in). The surface reflection makes water shallower than about 0.9 m (3 ft) difficult to resolve, and absorption limits

7906-522: Is the study of the interactions among a collection of species that inhabit the same geographic area. Community ecologists study the determinants of patterns and processes for two or more interacting species. Research in community ecology might measure species diversity in grasslands in relation to soil fertility. It might also include the analysis of predator-prey dynamics, competition among similar plant species, or mutualistic interactions between crabs and corals. These ecosystems, as we may call them, are of

8040-556: Is used for managing wildlife stocks and setting harvest quotas. In cases where basic models are insufficient, ecologists may adopt different kinds of statistical methods, such as the Akaike information criterion , or use models that can become mathematically complex as "several competing hypotheses are simultaneously confronted with the data." The concept of metapopulations was defined in 1969 as "a population of populations which go extinct locally and recolonize". Metapopulation ecology

8174-476: Is very difficult, if possible at all, to use the same technique in a lidar. The main problems are that all individual emitters must be coherent (technically coming from the same "master" oscillator or laser source), have dimensions about the wavelength of the emitted light (1 micron range) to act as a point source with their phases being controlled with high accuracy. Several companies are working on developing commercial solid-state lidar units but these units utilize

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8308-521: The Hughes Aircraft Company introduced the first lidar-like system in 1961, shortly after the invention of the laser. Intended for satellite tracking, this system combined laser-focused imaging with the ability to calculate distances by measuring the time for a signal to return using appropriate sensors and data acquisition electronics. It was originally called "Colidar" an acronym for "coherent light detecting and ranging", derived from

8442-646: The National Center for Atmospheric Research used it to measure clouds and pollution. The general public became aware of the accuracy and usefulness of lidar systems in 1971 during the Apollo ;15 mission, when astronauts used a laser altimeter to map the surface of the Moon. Although the English language no longer treats "radar" as an acronym, (i.e., uncapitalized), the word "lidar" was capitalized as "LIDAR" or "LiDAR" in some publications beginning in

8576-405: The abundance or biomass at each level. When the relative abundance or biomass of each species is sorted into its respective trophic level, they naturally sort into a 'pyramid of numbers'. Species are broadly categorized as autotrophs (or primary producers ), heterotrophs (or consumers ), and Detritivores (or decomposers ). Autotrophs are organisms that produce their own food (production

8710-436: The logistic equation by Pierre Verhulst : where N(t) is the number of individuals measured as biomass density as a function of time, t , r is the maximum per-capita rate of change commonly known as the intrinsic rate of growth, and α {\displaystyle \alpha } is the crowding coefficient, which represents the reduction in population growth rate per individual added. The formula states that

8844-416: The time of flight of the laser pulse (i.e., the time it takes each laser pulse to hit the target and return to the sensor), which requires the pulsing of the laser and acquisition by the camera to be synchronized. The result is a camera that takes pictures of distance, instead of colors. Flash lidar is especially advantageous, when compared to scanning lidar, when the camera, scene, or both are moving, since

8978-506: The 1980s. No consensus exists on capitalization. Various publications refer to lidar as "LIDAR", "LiDAR", "LIDaR", or "Lidar". The USGS uses both "LIDAR" and "lidar", sometimes in the same document; the New York Times predominantly uses "lidar" for staff-written articles, although contributing news feeds such as Reuters may use Lidar. Lidar uses ultraviolet , visible , or near infrared light to image objects. It can target

9112-551: The Earth and atmospheric conditions within a narrow self-regulating range of tolerance. Population ecology studies the dynamics of species populations and how these populations interact with the wider environment. A population consists of individuals of the same species that live, interact, and migrate through the same niche and habitat. A primary law of population ecology is the Malthusian growth model which states, "a population will grow (or decline) exponentially as long as

9246-627: The Inspector General. Auditor-in-Charge J. Kirk McGill determined that NEON, Inc. had poor control over taxpayer funds and could easily go over budget with little or no warning. He also found that NEON, Inc. had spent taxpayer funds on illegal expenditures including alcohol, lobbying, parties, and luxury travel. When McGill's findings were not addressed, he disclosed the matter directly to Congress. Hearings were held in 2014 and 2015. The House Committee on Science, Space, and Technology ultimately substantiated McGill's allegations, and NEON, Inc.,

9380-565: The United States, including Alaska , Hawaii and Puerto Rico . The observatory is among the first to detect and enable forecasting of ecological change at continental scales over multiple decades. NEON has partitioned the United States into 20 ecoclimatic domains, each of which represents different regions of vegetation, landforms, climate, and ecosystem performance. Data is collected by field technicians and passive sensors at strategically selected sites within each domain and synthesized into information products that can be used to describe changes in

9514-489: The atmosphere. Indeed, lidar has since been used extensively for atmospheric research and meteorology . Lidar instruments fitted to aircraft and satellites carry out surveying and mapping – a recent example being the U.S. Geological Survey Experimental Advanced Airborne Research Lidar. NASA has identified lidar as a key technology for enabling autonomous precision safe landing of future robotic and crewed lunar-landing vehicles. Wavelengths vary to suit

9648-831: The captured frames do not need to be stitched together, and the system is not sensitive to platform motion. This results in less distortion. 3-D imaging can be achieved using both scanning and non-scanning systems. "3-D gated viewing laser radar" is a non-scanning laser ranging system that applies a pulsed laser and a fast gated camera. Research has begun for virtual beam steering using Digital Light Processing (DLP) technology. Imaging lidar can also be performed using arrays of high speed detectors and modulation sensitive detector arrays typically built on single chips using complementary metal–oxide–semiconductor (CMOS) and hybrid CMOS/ Charge-coupled device (CCD) fabrication techniques. In these devices each pixel performs some local processing such as demodulation or gating at high speed, downconverting

9782-420: The city at a resolution of 30 cm (1 ft), displaying the precise height of rubble strewn in city streets. The new system is ten times better, and could produce much larger maps more quickly. The chip uses indium gallium arsenide (InGaAs), which operates in the infrared spectrum at a relatively long wavelength that allows for higher power and longer ranges. In many applications, such as self-driving cars,

9916-744: The context of the environment. It encompasses life processes, interactions, and adaptations ; movement of materials and energy through living communities; successional development of ecosystems; cooperation, competition, and predation within and between species ; and patterns of biodiversity and its effect on ecosystem processes. Ecology has practical applications in conservation biology , wetland management, natural resource management ( agroecology , agriculture , forestry , agroforestry , fisheries , mining , tourism ), urban planning ( urban ecology ), community health , economics , basic and applied science , and human social interaction ( human ecology ). The word ecology ( German : Ökologie )

10050-461: The data and is supported by existing workflows that support interpretation of 3-D point clouds . Recent studies investigated voxelisation . The intensities of the waveform samples are inserted into a voxelised space (3-D grayscale image) building up a 3-D representation of the scanned area. Related metrics and information can then be extracted from that voxelised space. Structural information can be extracted using 3-D metrics from local areas and there

10184-546: The data's purpose, the size of the area to be captured, the range of measurement desired, the cost of equipment, and more. Spaceborne platforms are also possible, see satellite laser altimetry . Airborne lidar (also airborne laser scanning ) is when a laser scanner, while attached to an aircraft during flight, creates a 3-D point cloud model of the landscape. This is currently the most detailed and accurate method of creating digital elevation models , replacing photogrammetry . One major advantage in comparison with photogrammetry

10318-714: The diversity of life from genes to ecosystems and spans every level of biological organization. The term has several interpretations, and there are many ways to index, measure, characterize, and represent its complex organization. Biodiversity includes species diversity , ecosystem diversity , and genetic diversity and scientists are interested in the way that this diversity affects the complex ecological processes operating at and among these respective levels. Biodiversity plays an important role in ecosystem services which by definition maintain and improve human quality of life. Conservation priorities and management techniques require different approaches and considerations to address

10452-530: The dynamic resilience of ecosystems that transition to multiple shifting steady-states directed by random fluctuations of history. Long-term ecological studies provide important track records to better understand the complexity and resilience of ecosystems over longer temporal and broader spatial scales. These studies are managed by the International Long Term Ecological Network (LTER). The longest experiment in existence

10586-456: The ecology and evolution of plants and animals. Ecological theory has also been used to explain self-emergent regulatory phenomena at the planetary scale: for example, the Gaia hypothesis is an example of holism applied in ecological theory. The Gaia hypothesis states that there is an emergent feedback loop generated by the metabolism of living organisms that maintains the core temperature of

10720-434: The energy is transferred through a chain of organisms by consumption. The simplified linear feeding pathways that move from a basal trophic species to a top consumer is called the food chain . Food chains in an ecological community create a complex food web. Food webs are a type of concept map that is used to illustrate and study pathways of energy and material flows. Empirical measurements are generally restricted to

10854-412: The entire field of view is illuminated with a wide diverging laser beam in a single pulse. This is in contrast to conventional scanning lidar, which uses a collimated laser beam that illuminates a single point at a time, and the beam is raster scanned to illuminate the field of view point-by-point. This illumination method requires a different detection scheme as well. In both scanning and flash lidar,

10988-408: The entire scene is illuminated at the same time. With scanning lidar, motion can cause "jitter" from the lapse in time as the laser rasters over the scene. As with all forms of lidar, the onboard source of illumination makes flash lidar an active sensor. The signal that is returned is processed by embedded algorithms to produce a nearly instantaneous 3-D rendering of objects and terrain features within

11122-460: The environment experienced by all individuals in the population remains constant." Simplified population models usually starts with four variables: death, birth, immigration , and emigration . An example of an introductory population model describes a closed population, such as on an island, where immigration and emigration does not take place. Hypotheses are evaluated with reference to a null hypothesis which states that random processes create

11256-451: The equilibrium, r / α {\displaystyle r/\alpha } as K , which is known as the "carrying capacity." Population ecology builds upon these introductory models to further understand demographic processes in real study populations. Commonly used types of data include life history , fecundity , and survivorship, and these are analyzed using mathematical techniques such as matrix algebra . The information

11390-514: The field of view of the sensor. The laser pulse repetition frequency is sufficient for generating 3-D videos with high resolution and accuracy. The high frame rate of the sensor makes it a useful tool for a variety of applications that benefit from real-time visualization, such as highly precise remote landing operations. By immediately returning a 3-D elevation mesh of target landscapes, a flash sensor can be used to identify optimal landing zones in autonomous spacecraft landing scenarios. Seeing at

11524-589: The flux of energy and matter through an environment. Ecosystems have biophysical feedback mechanisms that moderate processes acting on living ( biotic ) and abiotic components of the planet. Ecosystems sustain life-supporting functions and provide ecosystem services like biomass production (food, fuel, fiber, and medicine), the regulation of climate , global biogeochemical cycles , water filtration , soil formation , erosion control, flood protection, and many other natural features of scientific, historical, economic, or intrinsic value. The scope of ecology contains

11658-400: The former applies to a community's environment, whereas the latter applies to a species' environment. Definitions of the niche date back to 1917, but G. Evelyn Hutchinson made conceptual advances in 1957 by introducing a widely adopted definition: "the set of biotic and abiotic conditions in which a species is able to persist and maintain stable population sizes." The ecological niche

11792-544: The former relates only to the physical modifications of the habitat whereas the latter also considers the evolutionary implications of physical changes to the environment and the feedback this causes on the process of natural selection. Ecosystem engineers are defined as: "organisms that directly or indirectly modulate the availability of resources to other species, by causing physical state changes in biotic or abiotic materials. In so doing they modify, maintain and create habitats." The ecosystem engineering concept has stimulated

11926-518: The full ecological scope of biodiversity. Natural capital that supports populations is critical for maintaining ecosystem services and species migration (e.g., riverine fish runs and avian insect control) has been implicated as one mechanism by which those service losses are experienced. An understanding of biodiversity has practical applications for species and ecosystem-level conservation planners as they make management recommendations to consulting firms, governments, and industry. The habitat of

12060-471: The ground the non-vegetation data is obtained which may include objects such as buildings, electric power lines, flying birds, insects, etc. The rest of the points are treated as vegetation and used for modeling and mapping. Within each of these plots, lidar metrics are calculated by calculating statistics such as mean, standard deviation, skewness, percentiles, quadratic mean, etc. Multiple commercial lidar systems for unmanned aerial vehicles are currently on

12194-408: The herbivore trophic level, food webs are better characterized as a tangled web of omnivores." A keystone species is a species that is connected to a disproportionately large number of other species in the food-web . Keystone species have lower levels of biomass in the trophic pyramid relative to the importance of their role. The many connections that a keystone species holds means that it maintains

12328-406: The human and oceanic microbiomes . To a microbe , the human body is a habitat and a landscape. Microbiomes were discovered largely through advances in molecular genetics , which have revealed a hidden richness of microbial diversity on the planet. The oceanic microbiome plays a significant role in the ecological biogeochemistry of the planet's oceans. The largest scale of ecological organization

12462-408: The intensity of the returned signal. The name "photonic radar" is sometimes used to mean visible-spectrum range finding like lidar, although photonic radar more strictly refers to radio-frequency range finding using photonics components. A lidar determines the distance of an object or a surface with the formula : where c is the speed of light , d is the distance between the detector and

12596-404: The interplay among ecological processes that operate and influence patterns at different scales that grade into each other, such as transitional areas or ecotones spanning landscapes. Complexity stems from the interplay among levels of biological organization as energy, and matter is integrated into larger units that superimpose onto the smaller parts. "What were wholes on one level become parts on

12730-412: The interplay of development and environmental expression of traits. Resident species evolve traits that are fitted to the selection pressures of their local environment. This tends to afford them a competitive advantage and discourages similarly adapted species from having an overlapping geographic range. The competitive exclusion principle states that two species cannot coexist indefinitely by living off

12864-540: The laser is limited, or an automatic shut-off system which turns the laser off at specific altitudes is used in order to make it eye-safe for the people on the ground. One common alternative, 1,550 nm lasers, are eye-safe at relatively high power levels since this wavelength is not strongly absorbed by the eye. A trade-off though is that current detector technology is less advanced, so these wavelengths are generally used at longer ranges with lower accuracies. They are also used for military applications because 1,550 nm

12998-441: The laser repetition rate (which controls the data collection speed). Pulse length is generally an attribute of the laser cavity length, the number of passes required through the gain material (YAG, YLF , etc.), and Q-switch (pulsing) speed. Better target resolution is achieved with shorter pulses, provided the lidar receiver detectors and electronics have sufficient bandwidth. A phased array can illuminate any direction by using

13132-659: The laser, typically on the order of one microjoule , and are often "eye-safe", meaning they can be used without safety precautions. High-power systems are common in atmospheric research, where they are widely used for measuring atmospheric parameters: the height, layering and densities of clouds, cloud particle properties ( extinction coefficient , backscatter coefficient, depolarization ), temperature, pressure, wind, humidity, and trace gas concentration (ozone, methane, nitrous oxide , etc.). Lidar systems consist of several major components. 600–1,000  nm lasers are most common for non-scientific applications. The maximum power of

13266-402: The latter focuses on materials and energy fluxes. System behaviors must first be arrayed into different levels of the organization. Behaviors corresponding to higher levels occur at slow rates. Conversely, lower organizational levels exhibit rapid rates. For example, individual tree leaves respond rapidly to momentary changes in light intensity, CO 2 concentration, and the like. The growth of

13400-424: The lifespan of a single leaf. Each of those aphids, in turn, supports diverse bacterial communities. The nature of connections in ecological communities cannot be explained by knowing the details of each species in isolation, because the emergent pattern is neither revealed nor predicted until the ecosystem is studied as an integrated whole. Some ecological principles, however, do exhibit collective properties where

13534-432: The lower adjacent level (according to ecological pyramids ) nearer the abiotic source." Links in food webs primarily connect feeding relations or trophism among species. Biodiversity within ecosystems can be organized into trophic pyramids, in which the vertical dimension represents feeding relations that become further removed from the base of the food chain up toward top predators, and the horizontal dimension represents

13668-415: The major sea floor mapping program. The mapping yields onshore topography as well as underwater elevations. Sea floor reflectance imaging is another solution product from this system which can benefit mapping of underwater habitats. This technique has been used for three-dimensional image mapping of California's waters using a hydrographic lidar. Airborne lidar systems were traditionally able to acquire only

13802-464: The market. These platforms can systematically scan large areas, or provide a cheaper alternative to manned aircraft for smaller scanning operations. The airborne lidar bathymetric technological system involves the measurement of time of flight of a signal from a source to its return to the sensor. The data acquisition technique involves a sea floor mapping component and a ground truth component that includes video transects and sampling. It works using

13936-620: The maximum depth. Turbidity causes scattering and has a significant role in determining the maximum depth that can be resolved in most situations, and dissolved pigments can increase absorption depending on wavelength. Other reports indicate that water penetration tends to be between two and three times Secchi depth. Bathymetric lidar is most useful in the 0–10 m (0–33 ft) depth range in coastal mapping. On average in fairly clear coastal seawater lidar can penetrate to about 7 m (23 ft), and in turbid water up to about 3 m (10 ft). An average value found by Saputra et al, 2021,

14070-558: The most various kinds and sizes. They form one category of the multitudinous physical systems of the universe, which range from the universe as a whole down to the atom. Tansley (1935) Ecosystems may be habitats within biomes that form an integrated whole and a dynamically responsive system having both physical and biological complexes. Ecosystem ecology is the science of determining the fluxes of materials (e.g. carbon, phosphorus) between different pools (e.g., tree biomass, soil organic material). Ecosystem ecologists attempt to determine

14204-570: The nation's ecosystem through space and time. NEON data products are freely available via a web portal. The data NEON collects are defined by a series of Grand Challenges, as identified by the National Research Council at the request of the National Science Foundation. The National Research Council established a committee to evaluate the major ecological, environmental, and national concerns that require

14338-456: The nature of the unique physical environments that shapes the biodiversity within each. A more recent addition to ecosystem ecology are technoecosystems , which are affected by or primarily the result of human activity. A food web is the archetypal ecological network . Plants capture solar energy and use it to synthesize simple sugars during photosynthesis . As plants grow, they accumulate nutrients and are eaten by grazing herbivores , and

14472-400: The new system will lower costs by not requiring a mechanical component to aim the chip. InGaAs uses less hazardous wavelengths than conventional silicon detectors, which operate at visual wavelengths. New technologies for infrared single-photon counting LIDAR are advancing rapidly, including arrays and cameras in a variety of semiconductor and superconducting platforms. In flash lidar,

14606-573: The niche is called the ecotope , which is defined as the full range of environmental and biological variables affecting an entire species. Organisms are subject to environmental pressures, but they also modify their habitats. The regulatory feedback between organisms and their environment can affect conditions from local (e.g., a beaver pond ) to global scales, over time and even after death, such as decaying logs or silica skeleton deposits from marine organisms. The process and concept of ecosystem engineering are related to niche construction , but

14740-531: The number of nitrogen fixers , can lead to disproportionate, perhaps irreversible, changes in the system properties." Biodiversity refers to the variety of life and its processes. It includes the variety of living organisms, the genetic differences among them, the communities and ecosystems in which they occur, and the ecological and evolutionary processes that keep them functioning, yet ever-changing and adapting. Noss & Carpenter (1994) Biodiversity (an abbreviation of "biological diversity") describes

14874-402: The object or surface being detected, and t is the time spent for the laser light to travel to the object or surface being detected, then travel back to the detector. The two kinds of lidar detection schemes are "incoherent" or direct energy detection (which principally measures amplitude changes of the reflected light) and coherent detection (best for measuring Doppler shifts, or changes in

15008-399: The observed data. In these island models, the rate of population change is described by: where N is the total number of individuals in the population, b and d are the per capita rates of birth and death respectively, and r is the per capita rate of population change. Using these modeling techniques, Malthus' population principle of growth was later transformed into a model known as

15142-406: The organization and structure of entire communities. The loss of a keystone species results in a range of dramatic cascading effects (termed trophic cascades ) that alters trophic dynamics, other food web connections, and can cause the extinction of other species. The term keystone species was coined by Robert Paine in 1969 and is a reference to the keystone architectural feature as the removal of

15276-504: The phase of the reflected light). Coherent systems generally use optical heterodyne detection . This is more sensitive than direct detection and allows them to operate at much lower power, but requires more complex transceivers. Both types employ pulse models: either micropulse or high energy . Micropulse systems utilize intermittent bursts of energy. They developed as a result of ever-increasing computer power, combined with advances in laser technology. They use considerably less energy in

15410-468: The published work of George Perkins Marsh ("Man and Nature"). Within an ecosystem, organisms are linked to the physical and biological components of their environment to which they are adapted. Ecosystems are complex adaptive systems where the interaction of life processes form self-organizing patterns across different scales of time and space. Ecosystems are broadly categorized as terrestrial , freshwater , atmospheric, or marine . Differences stem from

15544-502: The rate of change in population size ( d N ( t ) / d t {\displaystyle \mathrm {d} N(t)/\mathrm {d} t} ) will grow to approach equilibrium, where ( d N ( t ) / d t = 0 {\displaystyle \mathrm {d} N(t)/\mathrm {d} t=0} ), when the rates of increase and crowding are balanced, r / α {\displaystyle r/\alpha } . A common, analogous model fixes

15678-463: The reflected energy is detected and measured by sensors. Distance to the object is determined by recording the time between transmitted and backscattered pulses and by using the speed of light to calculate the distance traveled. Flash lidar allows for 3-D imaging because of the camera's ability to emit a larger flash and sense the spatial relationships and dimensions of area of interest with the returned energy. This allows for more accurate imaging because

15812-424: The same limiting resource ; one will always out-compete the other. When similarly adapted species overlap geographically, closer inspection reveals subtle ecological differences in their habitat or dietary requirements. Some models and empirical studies, however, suggest that disturbances can stabilize the co-evolution and shared niche occupancy of similar species inhabiting species-rich communities. The habitat plus

15946-401: The scanned area from the scanner's location to create realistic looking 3-D models in a relatively short time when compared to other technologies. Each point in the point cloud is given the colour of the pixel from the image taken at the same location and direction as the laser beam that created the point. Mobile lidar (also mobile laser scanning ) is when two or more scanners are attached to

16080-463: The signals to video rate so that the array can be read like a camera. Using this technique many thousands of pixels / channels may be acquired simultaneously. High resolution 3-D lidar cameras use homodyne detection with an electronic CCD or CMOS shutter . A coherent imaging lidar uses synthetic array heterodyne detection to enable a staring single element receiver to act as though it were an imaging array. In 2014, Lincoln Laboratory announced

16214-399: The site will disappear unless rescued by an adjacent source patch or environmental conditions become more favorable. Metapopulation models examine patch dynamics over time to answer potential questions about spatial and demographic ecology. The ecology of metapopulations is a dynamic process of extinction and colonization. Small patches of lower quality (i.e., sinks) are maintained or rescued by

16348-779: The sites being studied. This is accomplished by slow flying aircraft surveying at 1,000 meters above the ground. Aquatic site sampling depends on the type of environment, varying between streams, rivers, and lakes. Automated sensors assess water quality and depth and manual observations study organisms, biogeochemistry, hydrology, and morphology. Each terrestrial site studied by NEON includes 30 randomly distributed plots. At select plots, technicians monitor soil biogeochemistry and microbes; plant diversity, biogeochemistry, biomass, productivity, and leaf area index; beetle diversity; mosquito prevalence, diversity, phenology, and infectious disease; small mammal diversity, demography, and disease; avian diversity; and tick‐borne diseases. Each terrestrial site

16482-524: The study of ecology into a conceptually manageable framework, the biological world is organized into a nested hierarchy , ranging in scale from genes , to cells , to tissues , to organs , to organisms , to species , to populations , to guilds , to communities , to ecosystems , to biomes , and up to the level of the biosphere . This framework forms a panarchy and exhibits non-linear behaviors; this means that "effect and cause are disproportionate, so that small changes to critical variables, such as

16616-432: The sum of the components explain the properties of the whole, such as birth rates of a population being equal to the sum of individual births over a designated time frame. The main subdisciplines of ecology, population (or community ) ecology and ecosystem ecology , exhibit a difference not only in scale but also in two contrasting paradigms in the field. The former focuses on organisms' distribution and abundance, while

16750-527: The target: from about 10  micrometers ( infrared ) to approximately 250  nanometers ( ultraviolet ). Typically, light is reflected via backscattering , as opposed to pure reflection one might find with a mirror. Different types of scattering are used for different lidar applications: most commonly Rayleigh scattering , Mie scattering , Raman scattering , and fluorescence . Suitable combinations of wavelengths can allow remote mapping of atmospheric contents by identifying wavelength-dependent changes in

16884-449: The term " radar ", itself an acronym for "radio detection and ranging". All laser rangefinders , laser altimeters and lidar units are derived from the early colidar systems. The first practical terrestrial application of a colidar system was the "Colidar Mark II", a large rifle-like laser rangefinder produced in 1963, which had a range of 11 km and an accuracy of 4.5 m, to be used for military targeting. The first mention of lidar as

17018-670: The tree responds more slowly and integrates these short-term changes. O'Neill et al. (1986) The scale of ecological dynamics can operate like a closed system, such as aphids migrating on a single tree, while at the same time remaining open about broader scale influences, such as atmosphere or climate. Hence, ecologists classify ecosystems hierarchically by analyzing data collected from finer scale units, such as vegetation associations , climate, and soil types , and integrate this information to identify emergent patterns of uniform organization and processes that operate on local to regional, landscape , and chronological scales. To structure

17152-415: The underlying causes of these fluxes. Research in ecosystem ecology might measure primary production (g C/m^2) in a wetland in relation to decomposition and consumption rates (g C/m^2/y). This requires an understanding of the community connections between plants (i.e., primary producers) and the decomposers (e.g., fungi and bacteria). The underlying concept of an ecosystem can be traced back to 1864 in

17286-439: The use of a location by the animal." For example, a habitat might be an aquatic or terrestrial environment that can be further categorized as a montane or alpine ecosystem. Habitat shifts provide important evidence of competition in nature where one population changes relative to the habitats that most other individuals of the species occupy. For example, one population of a species of tropical lizard ( Tropidurus hispidus ) has

17420-495: The vectors of discrete points while DEM and DSM are interpolated raster grids of discrete points. The process also involves capturing of digital aerial photographs. To interpret deep-seated landslides for example, under the cover of vegetation, scarps, tension cracks or tipped trees airborne lidar is used. Airborne lidar digital elevation models can see through the canopy of forest cover, perform detailed measurements of scarps, erosion and tilting of electric poles. Airborne lidar data

17554-429: The wavelength of light. It has also been increasingly used in control and navigation for autonomous cars and for the helicopter Ingenuity on its record-setting flights over the terrain of Mars . The evolution of quantum technology has given rise to the emergence of Quantum Lidar, demonstrating higher efficiency and sensitivity when compared to conventional lidar systems. Under the direction of Malcolm Stitch,

17688-593: Was coined in 1866 by the German scientist Ernst Haeckel . The science of ecology as we know it today began with a group of American botanists in the 1890s. Evolutionary concepts relating to adaptation and natural selection are cornerstones of modern ecological theory . Ecosystems are dynamically interacting systems of organisms, the communities they make up, and the non-living ( abiotic ) components of their environment. Ecosystem processes, such as primary production , nutrient cycling , and niche construction , regulate

17822-571: Was dismissed from the project. This represents one of the largest Federal agreement terminations for cause in history. The NSF chose Battelle to complete the construction of the observatory. NEON has categorized five types of measurement systems: the Airborne Observation Platform, Aquatic Instrument System, Aquatic Observation System, Terrestrial Instrument System, and Terrestrial Observation System. NEON takes airborne photography and performs aerial LiDAR observations of

17956-731: Was initially conceived in 2000, with a preliminary plan being developed in 2006. The National Science Foundation, the National Science Board and Congress approved funding for NEON in 2011. The program was fully operational in 2019. Beginning in 2011, NEON, Inc., the entity in charge of initially running the NEON project, was audited by the Defense Contract Audit Agency on behalf of the National Science Foundation Office of

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