Human footprint models provide important insights into the influence of humans within ecosystems [ 18 , 19 ]. They can act as a relevant predictor for biogeographic processes and, as a consequence, can be an important consideration in Species Distribution Models SDMs [ 20 ]. Human footprint modelling has been undertaken across the globe e. Nevertheless, up to c. In addition, information on human presence and activities may be difficult to compile as over 30 nations are active in the region, each with varying amounts of permanent infrastructure distributed over different areas of the continent [ 24 ] and with highly variable formats for national reporting on activities conducted by operators see for instance [ 26 ] on permit allocation, and [ 27 ] on biosecurity.
As a result only a few regional or local attempts to measure human footprint in Antarctica have been undertaken. A recent study [ 28 ] mapped the footprint of the British national Antarctic programme the British Antarctic Survey; BAS over the previous 70 years, in terms of infrastructure location and expedition visitation across the Antarctic Peninsula region, and observed substantial spatial and temporal variability. Chown and colleagues [ 1 ] evaluated the risk of biological invasions to the continent by mapping areas of human settlement and visitation and environments with climates suitable for potential invaders.
Such locations could be also vulnerable to the introduction of disease microorganism [ 30 ]. The work of Chown and colleagues [ 1 ] indirectly provided a first insight on the extent of human footprint across the continent; however, the pressure metric applied was based purely on human densities, and related to other variables specifically directed to estimate the biological risk of non-native species establishment.
Furthermore, the risk map generated was limited to a spatial resolution of 50 x 50 km. Other authors have displayed the distribution of Antarctic facilities [ 23 ], quantified tourism industry vessel routes around the Antarctic Peninsula [ 31 , 32 ] and examined levels of visitation to protected areas [ 26 , 33 ]. Collectively, these studies reveal that substantialt parts of ice-free Antarctica are not currently free from human activities and resulting impacts, making a precise view of current spatial pressure, which has resulted from past temporary or permanent activities, essential for local and continent-wide policy development and management action [ 34 , 35 , 36 ].
In this work, we assimilated available datasets and reproduced the approach of Sanderson and colleagues [ 21 ] to generate a high-resolution multidimensional formula showing the comparative spatial human footprint across Antarctica at a small scale 30 arcsec. This system integrated all recurrent elements, i. To demonstrate a potential application of the footprint model we incorporated the Antarctic IBA data to investigate the vulnerability of bird populations to local human activities and considered the level of protection currently afforded to these areas under the Antarctic Treaty System.
In this study, human footprint was considered to be the spatial pressure on Antarctic ice-free ground, caused either by the existing i. Footprint mapping was undertaken using ArcGIS Five spatial features relating to different human capabilities were aggregated in the development of the Antarctic footprint model. Every ice-free pixel covered 30 arcseconds, which is equal to 0. This system aimed to retain geodesic pixel size and directly match standards for world scale analyses [ 22 ]. Each pixel had assigned a score ranging from 1 to 10 per feature based on the following rules see below.
It should be noted that in all features when one pixel fell to more than one category of the same feature the highest score among them was assigned. Smaller facilities, including all camps, refuges, aerodromes and small stations accommodating fewer than 10 people, or where no information was available, were placed into another land cover feature category with a built-up area of radius m and given a score of 8 out of Visitor landing sites: the coordinates supplied by the International Association of Antarctica Tour Operators IAATO for all designed visitor sites within the Antarctic Peninsula were considered as landing sites with a radius of m and given a value of 9 out of 10 for each site to reflect potential land transformation.
These sites were given a value of 5 out of Protected areas: entry to each Antarctic Specially Protected Area ASPA is allowed only in accordance with a permit provided by an appropriate national authority typically a government agency and, consequently, these protected areas were considered as a separate category in the model.
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A score of 3 out of 10 was given to these areas. Antarctic Specially Management Areas, which are designated to help facilitate co-ordination of human activities within an area, were not incorporated as they generally overlapped with high score categories. Remote sites: remaining ice-free areas were classified as remote sites, and given a score of 1 out of Although there are no inhabitants living permanently in Antarctica we generated this index by the addition of likely individual periods of residence or visitation:.
For stations operating only seasonally and seasonal camps, we corrected this value by incorporating an estimated operational period duration of four months and two months, respectively.
Steven Chown – Research Output — Monash University
Therefore, the formulae were:. Therefore the formula was:. Therefore, the formula was:. Three separate dimensions were considered during the calculation of accessibility to ice-free areas, with their corresponding scores accounted separately: 1 coastal access from shipping, 2 terrestrial access from facilities and 3 airborne access from aerodromes.
Inclusion of existing terrestrial routes was considered for the calculations, but due to the absence of centralized information on paths, tracks and roads this feature was neglected; thus we acknowledge a limitation within the study to establish the exact routes of overland movement. The scoring system was created using a radial buffer zoning based on walking distances from the nearest coast 1, 2, 4, 8 km, and so on…. All ice-free areas separated from coasts were given a value of 1.
The scoring system was also created using radial buffer zoning see S3 Table. For example, a value of 5 was given to a radius zone of 16—32 km, which was considered to be a maximum walkable distance per day. Taking into consideration the flight endurance of a typically employed small aircraft such as a DeHavilland Twin Otter or Dornier and allowing for return trips, ice-free ground within a radius of km of each airstrip was considered within normal operational range for land based aircraft operations within Antarctica.
It was noted that greater distances may be covered by larger aircraft such as the Lockheed C Hercules, Lockheed C-5 Galaxy or Boeing C but flights greater than km were not differentiated here all scored as 1. In turn, movement of helicopters from ships were not quantified, thus their ship-based capabilities were only partially assessed within the coastal accessibility dimension.
To obtain the aggregated human footprint score for each ice free site, the values from the five features analyzed within the Antarctic continent were added and obtained scores ranging from 5 to Data were then re-scaled to the range 1 to to allow direct comparison with maps created for other parts of the world and thereby allow integration with spatial modeling datasets outside Antarctica [ 21 , 22 ].
In addition, the scores for large scale infrastructure on permanent ice e. Harris et al. The report reviewed available and historic information on different bird species populations throughout Antarctica and generated a list of IBAs. We used information contained within this report as a basis for our work to demonstrate a potential application of the footprint model to investigate the potential vulnerability of bird populations to local human pressure. The human footprint value for each IBA point location was obtained using the footprint model described in this paper.
Values for bird colonies within IBAs located on ice, such as emperor penguin colonies, were manually calculated following the principles described earlier.
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We calculated the percentage of Antarctic bird species estimated global populations breeding pairs contained within IBAs that were also afforded legal protection through their designation as Antarctic Specially Protected Areas ASPAs. The estimated global populations breeding pairs of bird species were obtained from information collated by [ 5 ] from a range of literature sources [ 9 , 38 , 39 , 40 , 41 , 42 , 43 ]. Bird population numbers within each IBA were also derived from [ 5 ] where the original source references for the available population data can be seen for each species within each IBA.
Within IBAs substantial variability in bird population counts may have been recorded in different years, so in this assessment the most recent counts were generally used. Modelling of the current distribution of human activities in Antarctica revealed a footprint that was largely concentrated in the northern Antarctic Peninsula region and southern Victoria Land, as well as several isolated and predominantly coastal areas in East Antarctica Fig 1 and S4 Table. Compared to other areas of the world, large expanses of Antarctica remain relatively unvisited by humans, including much of Marie Byrd Land and inland areas such as the Transantarctic, Ellsworth and Prince Charles Mountains.
The Antarctic Peninsula scored some of the highest footprint values, and in particular the ice-free areas of the South Shetland Islands and northern Antarctic Peninsula, where numerous stations and visitor sites are concentrated Fig 2. Notably, the vicinity of Frei, Escudero, Bellinghausen and Great Wall stations on Fildes Peninsula King George Island, South Shetland Islands displays the largest cluster of pixels in the Antarctic Peninsula region with a footprint score of over 90 across an area of c.
In contrast, footprint values on the eastern side of the Antarctic Peninsula was substantial only at latitudes above c. Fig 3 shows the distribution of human footprint values across all IBAs, with colonies subject to the highest human footprint located predominantly around the northern Antarctic Peninsula. Table 1 shows the 10 most potentially vulnerable IBAs based upon human footprint values and also details the triggers for the allocation of IBA status and the area management tools employed by the Antarctic Treaty System.
Some IBAs are located in close proximity to established research stations and visitors sites, resulting in a high footprint value. However, some areas identified as potentially vulnerable to local human activity have no formal internationally agreed area management e. IBA No.
Substantial variability in the percentage of bird species protection within ASPAs was noted. Insufficient data was available to make an assessment for some species, including the macaroni penguin Eudyptes chrysolophus , which has been categorized as Vulnerable by the IUCN Table 3. Footprint score 20—39 green , 40—59 yellow , 60—79 orange , as shown in Fig 3. This study completes the mapping of global human footprint by producing the first continent-wide map for terrestrial Antarctica [ 21 , 22 ]. At a continent-wide scale human footprint was much lower than most other areas of the Earth.
However, at a regional spatial scale, footprint was often correlated with accessibility to ice-free land by sea.
For example, in the Ross Sea region the accessible coastline hosts several facilities and human footprint values are correspondingly high, while the values for the remote, uninhabited and largely land-locked Transantarctic Mountains were comparatively low. In some areas, ice-free coastal sites of large extent were often found to be subject to greater human activity than those of smaller extent. For example, on the South Shetland Islands, most major ice-free promontories were sites of substantial human activity or infrastructure Fig 2.
This may indicate that the availability of ice-free ground for further human colonization at some locations may be reaching a limit, and notably on the northern Antarctic Peninsula and offshore islands. Importantly, this means that substantial amounts of ground free of direct human activity and associated impacts including wildlife disturbance and habitat destruction are no longer available to indigenous flora and fauna.
The designation of Antarctic Specially Protected Areas ASPAs generally reduced the human footprint values of the selected areas, as entry to these sites is conditional upon visitors obtaining permits, which are generally only allocated for scientific or environmental management purposes. Nevertheless, ASPAs close to existing research stations often had relatively high footprint values, as access by scientific staff was more readily achievable Hughes et al. It should be highlighted that the generated maps e.
Furthermore, the footprint model incorporates data relevant to the current distribution of infrastructure and human activity; however, the addition of a temporal element to the model may allow insight into cumulative impacts at sites or across the continent as a whole Hughes et al. Thus, a limitation of the study is the capacity to detect the exact levels of disturbance experienced by Antarctic terrestrial species at the most vulnerable stages of their life cycles such breeding or moulting.
However, since most human activities in Antarctica peak in the austral summer period considerable interference could be expected. Moreover, the picture of human footprint presented here is generated from information on present activities —16 and does not reflect the cumulative historical occupation of the sites. Therefore, it should be viewed as an indication of the current pressures to Antarctic ecosystems, and therefore subjected to changes with time.
Climate change and expanding human footprint are having an increasing impact upon Antarctic terrestrial ecosystems and their synergistic action may increase conservation challenges across the continent and beyond [ 1 , 2 , 35 ]. It is the responsibility of the Antarctic Treaty Consultative Meeting to ensure the agreed principles within the Protocol on Environmental Protection to the Antarctic Treaty are applied, taking into consideration specialist advice provided by the Committee for Environmental Protection.
Dartnall 6. Convey, S. Chown 7. Hennion, A. Huiskes, S. Robinson, P. Convey 8. Skotnicki, P. Selkirk 9. Stevens, I. Hogg Convey, Y. Frenot, N. Gremmen, D. Bergstrom Quesada, W.
Convey, P. (Pete)
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https://j-a-x.net/wp-content/bestpreis-hydroxychloroquin-200mg-versand.php Pienitz Convey Lyons, J. Buy Hardcover. Buy Softcover. FAQ Policy. About this book The Antarctic provides a suite of scenarios useful for investigating the range of climate change effects on terrestrial and limnetic biota. Show all. From the reviews: "The book is described as "a milestone as it has collected the most actual facts about the Antarctic region and allows us to look at the phenomenon from physical and biological perspectives.
Ellis-Evans , British Antarctic Survey, Cambridge, UK " This book is a much needed, and comprehensive evaluation of the global changes affecting the ice-free ecosystems of the Antarctic. Colonisation Processes Pages Hughes, K. Biogeography Pages Chown, S. Biological Invasions Pages Convey, P. Show next xx. Recommended for you.