Find research datasets worth reusing

opencc-by-4.0Jan 2020View details →

UBL000038770 - Tweeden placaet-bovck: inhovdende diversche ordonnancien, edicten, ende placaetē vande Coninclicke Ma.ten ende ... grauen van Vlaendren, metsgaders ... Prouincialen Raede aldaer, ghepubliceert inden voorghenoemden lande van Vlaendren t'zedert den iaere vyfthien-hondert t'zestich, tot ende metten iaere zesthien-hondert neghenen-twintich

Titel:  Tweeden placaet-bovck: inhovdende diversche ordonnancien, edicten, ende placaetē vande Coninclicke Ma.ten ende ... grauen van Vlaendren, metsgaders ... Prouincialen Raede aldaer, ghepubliceert inden voorghenoemden lande van Vlaendren t'zedert den iaere vyfthien-hondert t'zestich, tot ende metten iaere zesthien-hondert neghenen-twintich Publisher: Anna vanden Steene, F.a Ians Place: Gent Year: 1629 Used version: The copy we used for the transcriptions is held at Leiden University Library and digitised by the KB National Library of the Netherlands. Link digitised version of the book: https://books.google.nl/books?id=ptMn82qzfyQC (Main) Language: Dutch. Province: Vlaanderen Font: Romein. Model used: Dutch_Romantype_Print. Version of Transkribus used: v.1.9.1. Other info: Abbyy FineReader v.11 has been used. Link model: For more information on the HTR-model used, please visit: <a href="https://lab.kb.nl/dataset/entangled-histories-ordinances-low-countries">https://lab.kb.nl/dataset/entangled-histories-ordinances-low-countries</a>. Transcription conventions: <ul> <li> The abbreviations have been written out into full words. </li> <li> The hyphens at the end of a line have been kept (when there). </li> </ul> If you are in need of the original scans of the documents, please contact <a href="mailto:xxxxxx@kb.nl">dataservices@kb.nl</a>. This transcription is part of the dataset created with the ‘Entangled Histories’-project. PI: dr. C.A. Romein; Scientific Programmer: S.F. Veldhoen, MSc; Project Manager: drs. M. de Gruijter.

opencc-by-sa-4.0Jan 2020View details →

Potential distribution of land cover classes (Potential Natural Vegetation) at 250 m spatial resolution

Potential distribution of land cover classes (Potential Natural Vegetation) at 250 m spatial resolution based on a compilation of data sets (Biome6000k, Geo-Wiki, LandPKS, mangroves soil database, and from various literature sources; total of about 65,000 training points). We used a comparable thematic legend used to produce the Dynamic Land Cover 100m: Version 2. Copernicus Global Land Operations product (Buchhorn et al. 2019), which is based on the UN FAO Land Cover Classification System (LCCS), so that users can compare actual (https://lcviewer.vito.be/) vs potential (this data set) land cover. Two classes not available in the LCCS were added: "subtropical/tropical mangrove vegetation" and "sub-polar or polar barren-lichen-moss, grassland". The map was created using relief and climate variables representing conditions the climate for the last 20+ years and predicted at 250 m globally using an Ensemble Machine Learning approach as implemented in the mlr package for R. Processing steps are described in detail <a href="https://github.com/Envirometrix/PNVmaps">here</a>. Maps with "_sd_" contain estimated model errors per class. Antarctica is not included. Produced for the needs of the <a href="https://naturemap.earth/">NatureMap</a> which is project run by the International Institute for Applied Systems Analysis (IIASA), the International Institute for Sustainability (IIS), the UN Environment Programme World Conservation Monitoring Centre (UNEP-WCMC), and the UN Sustainable Development Solutions Network (SDSN). NatureMap is funded by Norway’s International Climate Initiative (NICFI). Maps will also be made available via: <a href="https://OpenLandMap.org">OpenLandMap.org</a>. These are initial predictions for testing purposes only. A publication explaining all processing steps is pending. If you discover a bug, artifact or inconsistency in the predictions, or if you have a question please use some of the following channels: <ul> <li>Technical issues and questions about the code: <a href="https://github.com/Envirometrix/PNVmaps/issues">https://github.com/Envirometrix/PNVmaps/issues</a></li> </ul> All files internally compressed using "COMPRESS=DEFLATE" creation option in GDAL. File naming convention: <ul> <li>pnv = theme: potential natural vegetation,</li> <li>potential.landcover = variable: potential land cover type (e.g. "open forest, evergreen needleleaf"),</li> <li>probav.lc100 = classification model: ProbaV-based land cover mapping legend (LCCS),</li> <li>c = factor,</li> <li>250m = spatial resolution / block support: 250 m,</li> <li>b0..0cm = vertical reference: land surface,</li> <li>2000..2017 = time reference: period 2000-2017,</li> <li>v0.1 = version number: 0.1,</li> </ul>

opencc-by-4.0Feb 2020View details →

Land use and cover (LUC) rasters of the São Lourenço River Basin (2002 - 2014)

The LUC dataset of São Lourenço river basin, a major Pantanal wetland contribution area as provided by the 4th edition of the <a href="https://www.embrapa.br/pantanal/bacia-do-alto-paraguai">Monitoring of Changes in Land cover and Land Use in the Upper Paraguay River Basin - Brazilian portion - Review Period: 2012 to 2014</a> (Embrapa Pantanal, Instituto SOS Pantanal, and WWF-Brasil 2015). For the development of the <a href="https://reginalexavier.github.io/OpenLand/index.html">OpenLand R package</a> (tests and <a href="https://reginalexavier.github.io/OpenLand/articles/openland_vignette.html">vignettes</a>), the original multi-year shape file was clipped to the extent of São Lourenço basin, transformed into a 5-layer <a href="https://rdrr.io/cran/raster/man/stack.html"><code>RasterStack</code></a> and then saved as .RDA file which can be loaded into <a href="https://www.r-project.org/">R</a> (R Core Team, 2019). Five LUC maps (2002, 2008, 2010, 2012 and 2014) compose the time series. The study area of approximately 22,400 km2 is located in the Cerrado Savannah biom in the southeast of the Brazilian state of Mato Grosso. The category names and colors to be associated with the pixel values follow the conventions given by Instituto SOS Pantanal and WWF-Brasil (2015) <a href="https://www.embrapa.br/documents/1354999/1529097/BAP+-+Mapeamento+da+Bacia+do+Alto+Paraguai+-+estudo+completo/e66e3afb-2334-4511-96a0-af5642a56283">(access document here, page 17)</a>. The Portuguese legend acronyms were maintained as defined in the original dataset. The original legend from SOS Pantanal <pre><code class="language-markdown"> _______________________________________________________________________________________________ |Pixel Value |Legend | Class | Use | Category | Colour| |------------|--------|---------------|-------------------|-----------------------------|-------| |2 | Ap | Anthropogenic | Anthropogenic Use | Cattle farming |#FFE4B5| |3 | FF | Natural | NA | Forest formation |#228B22| |4 | SA | Natural | NA | Park savanna |#00FF00| |5 | SG | Natural | NA | Gramineous savanna |#CAFF70| |7 | aa | Anthropogenic | NA | Anthropogenized vegetation |#EE6363| |8 | SF | Natural | NA | Wooded savanna |#00CD00| |9 | Agua | Natural | NA | Water bodies |#436EEE| |10 | Iu | Anthropogenic | Anthropogenic Use | Urban areas |#FFAEB9| |11 | Ac | Anthropogenic | Anthropogenic Use | Crop farming |#FFA54F| |12 | R | Anthropogenic | Anthropogenic Use | Reforestation |#68228B| |13 | Im | Anthropogenic | Anthropogenic Use | Mining areas |#636363| </code></pre>

opencc-by-4.0Mar 2020View details →

Long-term effectiveness of sustainable land management practices to control runoff, soil erosion, and nutrient loss and the role of rainfall intensity in Mediterranean rainfed agroecosystems

This data set corresponds to the open-access article "Long-term effectiveness of sustainable land management practices to control runoff, soil erosion, and nutrient loss and the role of rainfall intensity in Mediterranean rainfed agroecosystems" published in CATENA. (<a href="https://doi.org/10.1016/j.catena.2019.104352">https://doi.org/10.1016/j.catena.2019.104352</a>), funded by he European Commission Horizon 2020 project Diverfarming [grant agreement 728003].

opencc-by-4.0Mar 2020View details →

Dar Es Salaam Very-High-Resolution Land Cover Map

This is a very-high-resolution land cover map of Dar es Salaam derived from satellite imagery (Pleiades, 0.5m resolution). The majority of the area is classified from a 2016 (July) image while a small part of it from two images collected in January and March 2018, respectively.  The pixel values related to the following legend: 5=tree 8=shadow 3=artificial ground surface 4=low vegetation 2=water 7=bare ground 1=building 113=high elevated buildings 112=medium elevated buildings 111=low elevated buildings The Out of Bag error of the product is 6,38% with the following class errors: Building = 0.035826 Water = 0.049934 Artificial Ground Surface = 0.077108 Low Vegetation = 0.108709 Tall Vegetation = 0.062278 Bare Ground = 0.13803 Shadow = 0.019872 References: [1] Grippa, Taïs, Moritz Lennert, Benjamin Beaumont, Sabine Vanhuysse, Nathalie Stephenne, and Eléonore Wolff. 2017. “An Open-Source Semi-Automated Processing Chain for Urban Object-Based Classification.” Remote Sensing 9 (4): 358. <a href="https://doi.org/10.3390/rs9040358">https://doi.org/10.3390/rs9040358</a>. [2] Grippa, Tais, Stefanos Georganos, Sabine G. Vanhuysse, Moritz Lennert, and Eléonore Wolff. 2017. “A Local Segmentation Parameter Optimization Approach for Mapping Heterogeneous Urban Environments Using VHR Imagery.” In Proceedings Volume 10431, Remote Sensing Technologies and Applications in Urban Environments II., edited by Wieke Heldens, Nektarios Chrysoulakis, Thilo Erbertseder, and Ying Zhang, 20. SPIE. <a href="https://doi.org/10.1117/12.2278422">https://doi.org/10.1117/12.2278422</a>. [3] Georganos, Stefanos, Taïs Grippa, Moritz Lennert, Sabine Vanhuysse, and Eleonore Wolff. 2017. “SPUSPO: Spatially Partitioned Unsupervised Segmentation Parameter Optimization for Efficiently Segmenting Large Heterogeneous Areas.” In Proceedings of the 2017 Conference on Big Data from Space (BiDS’17). This dataset was produced in the frame of  REACT (<a href="http://react.ulb.be/">http://react.ulb.be</a>), funded by the Belgian Federal Science Policy Office (<a href="http://eo.belspo.be/About/Stereo3.aspx">BELSPO</a>).

opencc-by-4.0Apr 2020View details →

Fast Cash for Vacant Land | Sell my Land Fast California

Our mission is to relieve people from the burden of property ownership. If you’re looking for fast cash in exchange for your unwanted real estate, submit your property information to us today! We will make a cash offer on any piece of land, whatever the condition and situation! It doesn’t matter what kind of property you have, where it’s located or why you want to <a href="https://www.landmarkbuyers.com/">sell vacant land</a>, we are ready to give you a cash offer. We help landowners across the country who don’t want or can’t afford their parcel of vacant land. There are MANY reasons why landowners may want to liquidate their property and get cash: <ul> <li>To avoid foreclosure because of back due to taxes.</li> <li>To stop paying property taxes on a property that never gets used.</li> <li>To get rid of unattractive, undesirably vacant land in the middle of nowhere.</li> <li>When a real estate agent has the property on the market for months and it still won’t sell.</li> <li>When property owners inherit vacant land and they have no use for it.</li> <li>We don't care about the condition... we're interested!</li> </ul> We pay in cash for any kind of acreage including: <ul> <li>Farmland</li> <li>Forestry use land</li> <li>Rural Land</li> <li>Residential or commercial use land</li> <li>It doesn’t matter!</li> <li>Want a cash offer for your property?</li> </ul> Want to see how much you can get for your property? We make cash offers, we close quickly and we pay for all of your closing costs in the transaction. Just hit the button below and fill out the form for your offer! We’ll help you avoid paying transfer taxes, realtor commissions, and recording fees (among other things). Let us handle the hard work for you! Click to button below and let’s get started.

opencc-by-3.0Oct 2016View details →

Fig. 14 in New narrow-range endemic land snails from the sky islands of northern South Africa (Gastropoda: Streptaxidae and Urocyclidae)

Fig. 14. Sheldonia wolkbergensis sp. nov., holotype, shell diameter 7.7 mm (NMSA P0156/T4074).

opencc-by-3.0Nov 2012View details →

Map of Publish-or-Perish-Land

The map depicts the current situation of researchers being forced to publish or to perish. Focusing on electronic and Open Access publishing, the map is meant to visualize in an ironic manner the different paths researchers can take when being confronted with the question how and where to publish their works.

opencc-by-4.0May 2020View details →

GLASS Land Surface Temperature product (1981-2000): instantaneous LST

<ul> <li>GLASS Land Surface Temperature product (1981-2000): instantaneous LST have been produced from historical NOAA AVHRR data. The LST data were generated by integrating several Split-Window Algorithms with the Random Forest method (RF-SWA). The individual SWAs and the RF-SWA were trained and tested on simulation datasets obtained from globally representative atmospheric profiles. The validation against in-situ LST shows that the GLASS LST product has a precision of 1.18 K.</li> <li>The dataset is organized by year and a sample data is provided in simple.zip</li> <li>Further details can be found in the readme.pdf.</li> </ul>

opencc-by-4.0Jul 2020View details →

FAOSTAT Forest Land Emissions

The <a href="http://www.fao.org/faostat/en/#data/GF">Forest Land</a> dataset disseminates information on emissions and area change due to gain and losses of carbon stocks in living (aboveground and belowground) tree biomass. Estimates are computed following land Approach 1 and Tier 3 ( stock difference method) of the 2006 IPCC Guidelines for National GHG Inventories (IPCC, 2006). Data on carbon stocks and forest area used as input are those of the Forest Resources Assessment 2020 (FAO, 2020). Data are available by country, with global coverage and relative to the period 1990-2020. This domain contains data on net CO2 emissions/removals, associated implied emission factors and underlying activity data. The FAOSTAT Emissions data are estimated by FAO and do not coincide with GHG data reported by Parties to UNFCCC. FAOSTAT data and estimates support member countries to assess and report their emissions and removals. FAOSTAT emissions data are a global knowledge product.

opencc-zeroDec 2017View details →

Data from: Land-use change interacts with climate to determine elevational species redistribution

Climate change is driving global species redistribution with profound social and economic impacts. However, species movement is largely constrained by habitat availability and connectivity, of which the interaction effects with climate change remain largely unknown. Here we examine published data on 2798 elevational range shifts from 43 study sites to assess the confounding effect of land-use change on climate-driven species redistribution. We show that baseline forest cover and recent forest cover change are critical predictors in determining the magnitude of elevational range shifts. Forest loss positively interacts with baseline temperature conditions, such that forest loss in warmer regions tends to accelerate species' upslope movement. Consequently, not only climate but also habitat loss stressors and, importantly, their synergistic effects matter in forecasting species elevational redistribution, especially in the tropics where both stressors will increase the risk of net lowland biotic attrition.

Something is not quite right: effects of two land uses on anuran diversity in subtropical grasslands

Although habitat modification is considered one of the main causes of biodiversity loss, the relative contribution of different rural land uses to biodiversity conservation are far less known. Additionally, the realization of the multidimensionality of biodiversity demands studies integrating variation of functional traits and phylogenetic information as complements to address the effects of land use on the structure of animal communities. Herein, we investigated the effects of land use (i.e., intensive agricultural and extensive livestock rearing) on functional and phylogenetic diversity of anuran communities in farmland ponds from the Uruguayan savanna ecoregion, while considering the effects of local factors (i.e., water depth) on species composition. We surveyed adults and tadpoles in 22 ponds and quantified five traits related to tadpole feeding, habitat use, and predator avoidance. Tadpole identification was corroborated by DNA barcoding based on a fragment of the mitochondrial 16S rRNA gene. We observed a decline in phylogenetic mean nearest taxon distance associated with increase of surrounding agricultural land use. While land use intensification did not affect richness (functional or phylogenetic), ponds in livestock ranches hosted about four times more tadpoles than agricultural ponds. Functional evenness decreased with water depth, although such relationship disappeared when considering phylogenetic non-independence. Our results indicated that specific anuran clades were more sensitive to intensification in land use, reinforcing a recent view of phylogenetic homogenization following habitat conversion. Additionally, our study suggests that extensive cattle grazing over wide native pastures may provide an alternative more compatible with conservation than short-term crops in subtropical grasslands.

Influence of climate, soil and land cover on plant species distribution in the European Alps

Although the importance of edaphic factors and habitat structure for plant growth and survival is known, both are often neglected in favor of climatic drivers when investigating the spatial patterns of plant species and diversity. Yet, especially in mountain ecosystems with complex topography, missing edaphic and habitat components may be detrimental for a sound understanding of biodiversity distribution. Here, we compare the relative importance of climate, soil and land cover variables when predicting the distributions of 2'616 vascular plant species in the European Alps, representing approximately two thirds of all European Flora. Using presence-only data, we built point-process models (PPMs) to relate species observations to different combinations of covariates. We evaluated the PPMs through block cross-validations, and assessed the independent contributions of climate, soil and land cover covariates to predict plant species distributions using an innovative predictive partitioning approach. We found climate to be the most influential driver of spatial patterns in plant species with a relative influence of ~58.5% across all species, with decreasing importance from low to high elevations. Soil (~20.1%) and land cover (~21.4%), overall, were less influential than climate, but increased in importance along the elevation gradient. Furthermore, land cover showed strong local effects in lowlands, while the contribution of soil stabilized at mid-elevations. The decreasing influence of climate with elevation is explained by increasing endemism, and the fact that climate becomes more homogeneous as habitat diversity declines at higher altitudes. In contrast, soil predictors were found to follow the opposite trend. Additionally, at low elevations, human-mediated land cover effects appear to reduce the importance of climate predictors. We conclude that soil and land cover are, like climate, principal drivers of plant species distribution in the European Alps. While disentangling their effects remains a challenge, future studies can benefit markedly by including soil and land cover effects when predicting species distributions.

Data from: Thermal tolerance and the importance of microhabitats for Andean frogs in the context of land-use and climate change

1. Global warming is having impacts across the Tree of Life. Understanding species' physiological sensitivity to temperature change and how they relate to local temperature variation in their habitats is crucial to determining vulnerability to global warming. 2. We ask how species' vulnerability varies across habitats and elevations, and how climatically-buffered microhabitats can contribute to reduce their vulnerability. 3. We measured thermal sensitivity (critical thermal maximum – CTmax) of 14 species of Pristimantis frogs inhabiting young and old secondary, and primary forests in the Colombian Andes. Exposure to temperature stress was measured by recording temperature in the understory and across five microhabitats. We determined the frogs' current vulnerability across habitats, elevations and microhabitats accounting for phylogeny and then ask how vulnerability varies under four warming scenarios: +1.5⁰C, +2⁰C, +3⁰C and +5⁰C. 4. We found that CTmax was constant across species regardless of habitat and elevation. However, species in young secondary forests are expected to become more vulnerable because of increased exposure to higher temperatures. Microhabitat variation could enable species to persist within their thermal temperature range as long as regional temperatures do not surpass +2°C. The effectiveness of microhabitat buffering decreases with a 2-3°C increase, and is almost null under a 5°C temperature increase. 5. Microhabitats will provide thermal protection to Andean frog communities from climate change by enabling tracking of suitable climates through short distance movement. Conservation strategies, such as managing landscapes by preserving primary forests and allowing regrowth and re-connection of secondary forest would offer thermally buffered microhabitats and aid in the survival of this group.

Data from: Bird diversity and endemism along a land-use gradient in Madagascar: the conservation value of vanilla agroforests

<div> <div> Land-use change is the most important driver of biodiversity loss worldwide and particularly so in the tropics, where natural habitats are transformed into large-scale monocultures or heterogeneous landscape mosaics of largely unknown conservation value. Using birds as an indicator taxon, we evaluated the conservation value of a landscape mosaic in north-eastern Madagascar, a biodiversity hotspot and the center of global vanilla production. We assessed bird species richness and composition by conducting point counts across seven prevalent land-use types (forest- and fallow-derived vanilla agroforests, woody and herbaceous fallow that are part of a shifting cultivation system, rice paddy, forest fragment and contiguous old-growth forest). We find that old-growth forest had the highest species richness, driven by a high share of endemics. Species richness and community composition in forest-derived vanilla agroforest was similar to forest fragment, whereas fallow-derived vanilla agroforest was most comparable to woody fallow. The open land-use types herbaceous fallow and rice paddy had fewest species. Across forest fragment, vanilla agroforests and woody fallow, endemic bird species richness was positively correlated to landscape-scale forest cover. We conclude that both fallow- and forest-derived vanilla agroforests play an important but contrasting role for bird conservation in the landscape: Fallow-derived agroforests are less valuable but take fallow land out of the shifting cultivation cycle, possibly preventing further degradation. Conversely, forest-derived agroforests contribute to forest degradation but may avoid total loss of forest fragments. Considering the land-use history of agroforests may thus be a promising avenue for future research beyond the case of vanilla. </div> </div>

Best-practice forestry management delivers diminishing returns for coral reefs with increased land-clearing

Protection of coastal ecosystems from deforestation may be the best way to protect coral reefs from sediment runoff. However, given the importance of generating economic activities for coastal livelihoods, the prohibition of development is often not feasible. In light of this, logging codes-of-practice have been developed to mitigate the impacts of logging on downstream ecosystems. However, no studies have assessed whether managed land-clearing can occur in tandem with coral reef conservation goals. This study quantifies the impacts of current land use and the risk of potential logging activities on downstream coral reef condition and fisheries using a novel suite of linked land-sea models, using Kolombangara Island in the Solomon Islands as a case study. Further, we examine the ability of erosion reduction strategies stipulated in logging codes-of-practice to reduce these impacts as clearing extent increases. We found that with present-day land use, reductions in live and branching coral cover and increases in turf algae were associated with exposure to sediment runoff from catchments and log ponds. Critically, reductions in fish grazer abundance and biomass were associated with increasing sediment runoff, a functional group that accounts for ~25% of subsistence fishing. At low clearing extents, although best management practices minimises the exposure of coral reefs to increased runoff, it would still result in 32% of the reef experiencing an increase in sediment exposure. If clearing extent increased, best management practices would have no impact, with a staggering 89% of coral reef area at risk compared to logging with no management. Synthesis and applications: Assessing trade-offs between coastal development and protection of marine resources is a challenge for decision makers globally. Although development activities requiring clearing can be important for livelihoods, our results demonstrate that new logging in intact forest risks downstream resources important for both food and livelihood security. Importantly, our approach allows for spatially-explicit recommendations for where terrestrial management might best complement marine management. Finally, given the critical degradation feedback loops that increased sediment runoff can reinforce on coral reefs, minimising sediment runoff could play an important role in helping coral reefs recover from climate-related disturbances.

opencc-by-4.0Aug 2020View details →

Data and Software accompanying "Slope-aspect induced climate differences influence how water is exchanged between the land and atmosphere", submitted to JGR: Biogeosciences August 2020

This is a collection of all of the data files and python notebooks used in creating the manuscript "Slope-aspect induced climate differences influence how water is exchanged between the land and atmosphere", submitted to JGR: Biogeosciences August 2020.

opencc-by-4.0Aug 2020View details →

Satellite Data for Corn and Soybean Fields + Other Land Cover: Illinois, US, 2017-2019

These are the datasets associated with the paper: Hannah Kerner, Ritvik Sahajpal, Sergii Skakun, Inbal Becker-Reshef, Brian Barker, Mehdi Hosseini, Estefania Puricelli, and Patrick Gray. 2020. Resilient In-Season Crop Type Classification in Multispectral Satellite Observations using Growth Stage Normalization. In KDD ’20: ACM Special Interest Group (SIG) on Knowledge Discovery and Data Mining Conference Workshops, August 23–27, 2020, San Diego, CA.  The code that uses these datasets can be found at: <a href="https://github.com/nasaharvest/croptype-mapping-gsn/tree">https://github.com/nasaharvest/croptype-mapping-gsn</a>

Accelerated landings in stingless bees are triggered by visual threshold cues

Most flying animals rely primarily on visual cues to coordinate and control their trajectory when landing. Studies of visually-guided landing typically involve animals that decrease their speed before touchdown. Here, we investigate the control strategy of the stingless bee Scaptotrigona depilis, which instead accelerates when landing on its narrow hive entrance. By presenting artificial targets that resemble the entrance at different locations on the hive, we show that these accelerated landings are triggered by visual cues. We also found that S. depilis initiated landing and extended their legs when the angular size of the target reached a given threshold. Regardless of target size, the magnitude of acceleration was the same and the bees aimed for the same relative position on the target suggesting that S. depilis use a computationally simple but elegant 'stereotyped' landing strategy that requires few visual cues.