Content uploaded by Vassiliki I Kati
Author content
All content in this area was uploaded by Vassiliki I Kati
Content may be subject to copyright.
A preview of the PDF is not available
Roadless and Low-Traffic Areas as Conservation Targets in Europe
Abstract and Figures
With increasing road encroachment, habitat fragmentation by transport infrastructures has been a serious threat for European biodiversity. Areas with no roads or little traffic (“roadless and low-traffic areas”) represent relatively undisturbed natural habitats and functioning ecosystems. They provide many benefits for biodiversity and human societies (e.g., landscape connectivity, barrier against pests and invasions, ecosystem services). Roadless and low-traffic areas, with a lower level of anthropogenic disturbances, are of special relevance in Europe because of their rarity and, in the context of climate change, because of their contribution to higher resilience and buffering capacity within landscape ecosystems. An analysis of European legal instruments illustrates that, although most laws aimed at protecting targets which are inherent to fragmentation, like connectivity, ecosystem processes or integrity, roadless areas are widely neglected as a legal target. A case study in Germany underlines this finding. Although the Natura 2000 network covers a significant proportion of the country (16%), Natura 2000 sites are highly fragmented and most low-traffic areas (75%) lie unprotected outside this network. This proportion is even higher for the old Federal States (western Germany), where only 20% of the low-traffic areas are protected. We propose that the few remaining roadless and low-traffic areas in Europe should be an important focus of conservation efforts; they should be urgently inventoried, included more explicitly in the law and accounted for in transport and urban planning. Considering them as complementary conservation targets would represent a concrete step towards the strengthening and adaptation of the Natura 2000 network to climate change.
Electronic supplementary material
The online version of this article (doi:10.1007/s00267-011-9751-z) contains supplementary material, which is available to authorized users.
Figures - uploaded by Vassiliki I Kati
Author content
All figure content in this area was uploaded by Vassiliki I Kati
Content may be subject to copyright.
Supplementary resource (1)
Data
September 2011
... As the historical cradle of industrialization and transportation infrastructure, Europe has one of the world's heaviest human footprints. High anthropogenic pressure faces ecosystems across the continent [33][34][35]. The current dearth of broad-scale modelling approaches to analyse anthropogenic pressures in and around European PAs severely limits our understanding of effective biodiversity conservation on a continental scale [36]. ...
... In general, eastern European countries have lower population densities, have experienced delayed economic development, and have sparser road networks compared to central or western Europe. However, transportation infrastructure and urbanization have developed quickly in these countries since their accession to the EU [35]. This rapid development is likely to result in conflicts with conservation objectives in the future [16]. ...
... Given the importance of Romania's ecosystems for European biodiversity, Romania's relatively untouched N2k sites need careful monitoring and active management to protect them from future fragmentation. One existing legal framework for this effort is the Carpathian Convention (2003), which explicitly addresses regulations on traffic and development [35]. We argue that similar legal concepts addressing anthropogenic fragmentation should be incorporated into N2k management in order to strengthen its long-term viability for continent-wide biodiversity conservation. ...
Habitat loss from anthropogenic development has led to an unprecedented decline in global biodiversity. Protected areas (PAs) exist to counteract this degradation of ecosystems. In the European Union, the Natura 2000 (N2k) network is the basis for continent-wide conservation efforts. N2k is the world’s largest coordinated network of protected areas. However, threats to ecosystems do not stop at the borders of PAs. As measured by a landscape fragmentation metric, anthropogenic development can affect the interiors of PAs. To ensure the long-term viability of the N2k network of PAs, this paper attempts to quantify the degree to which N2k sites are insulated from development pressures. We use a comprehensive dataset of effective mesh density (seff) to measure aggregate fragmentation inside and within a 5 km buffer surrounding N2k sites. Our results show a strong correlation (R² = 0.78) between fragmentation (seff) within and around N2k sites. This result applies to all biogeographical regions in Europe. Only a narrow majority (58.5%) of N2k sites are less fragmented than their surroundings. Remote and mountainous regions in northern Europe, the Alps, parts of Spain, and parts of eastern Europe show the lowest levels of fragmentation. These regions tend to hold the largest N2k sites as measured by area. In contrast, central and western Europe show the highest fragmentation levels within and around N2k sites. 24.5% of all N2k sites are classified as highly to very-highly fragmented. N2k PA age since initial protection does not correlate with the difference in exterior and interior fragmentation of N2k PAs. These results indicate that PAs in Europe are not sheltered from anthropogenic pressures leading to fragmentation. Hence, we argue that there is a high potential for improving PA efficacy by taking pre-emptive action against encroaching anthropogenic fragmentation and by targeting scarce financial resources where fragmentation pressures can be mitigated through enforced construction bans inside PAs.
... Die Straßenökologie ist inzwischen zu einer relevanten Teildisziplin der angewandten Ökologie geworden (Selva et al., 2015(Selva et al., , 2011van der Ree et al., 2015). Globale Analysen zeigen, dass straßenlose Räume eine herausragende ökologische Bedeutung haben und dringlich eines verbesserten Schutzes bedürfen (Ibisch et al., 2016). ...
... Globale Analysen zeigen, dass straßenlose Räume eine herausragende ökologische Bedeutung haben und dringlich eines verbesserten Schutzes bedürfen (Ibisch et al., 2016). Viele Gründe sprechen dafür, vor allem in dicht besiedelten und stark von Infrastruktur erschlossenen Gebieten wie Mitteleuropa, die verbleibenden straßenlosen oder straßenarmen Regionen besonders zu schützen (Selva et al., 2015(Selva et al., , 2011 Auch die hier zu untersuchende oberhessische Region zwischen dem Vogelsberg und dem Kellerwald war in der jüngsten Vergangenheit zumindest von schwerer oder gar extremer Dürre betroffen. Vielerorts sind die Böden nach wie vor tiefgründig ausgetrocknet, und teilweise ist selbst im Spätherbst 2020 noch eine vergleichsweise geringe Wasserverfügbarkeit auch im Oberboden gegeben (vgl. ...
Bei der Prüfung von negativen Umweltwirkungen, die sich aus dem geplanten Autobahnbau in Oberhessen (A49) ergeben würden, wurden bislang thermische beziehungsweise mikroklimatische Effekte und ihre Relevanz im sich beschleunigt entfaltenden Klimawandel vernachlässigt. Autobahnen bewirken nicht nur eine physische, sondern auch eine thermische Zerschneidung. Sie erhöhen die auftretenden Maximaltemperaturen in der Landschaft sowie die Wasserverdunstung und bedingen zusätzlichen Hitze- und Trocknisstress bei Bäumen. Die Verdunstung und die austrocknende Wirkung von Luft wachsen nichtlinear mit steigender Temperatur an. Mithilfe von Satellitenbilddaten kann die kühlende Wirkung von Waldflächen in der betroffenen Region einschließlich des Dannenröder Forsts quantifiziert werden. Die Temperaturunterschiede sind vor allem an den heißesten Tagen des Jahres besonders ausgeprägt: Der Temperaturunterschied der durchschnittlichen Oberflächentemperaturen zwischen den kühlsten und bewaldeten Bereichen sowie den wärmsten urbanen Gebieten beträgt an diesen heißesten Tagen über 10 °C. Eine dichte und geschlossene bzw. vitale Vegetation vor allem von größeren Waldflächen wirkt sich deutlich kühlend auf die Oberflächentemperaturen aus. Vitalität und Kühlung von Vegetation beeinflussen sich wechselseitig. In Zeiträumen, in denen die Landschaft durch eine Vegetation mit geringer Vitalität geprägt ist (z. B. 2003 und 2016; gemessen durch den satellitenbasierten NDVI), fallen die Oberflächentemperaturen höher aus als in Jahren mit vergleichsweise hohen Vitalitätswerten der Vegetation (2007-2009). Hochaufgelöste satellitenbildbasierte Analysen (Landsat) zeigen, wie sehr sich Autobahnen im Untersuchungsgebiet an heißen Tagen aufheizen und einen entsprechenden thermischen Randeffekt auf den Wald ausüben. Es ist davon auszugehen, dass vor allem in Extremwitterungsperioden entlang der Autobahn eine erhöhte Baummortalität auftreten wird. Dadurch würden sich die negativen Folgen der Trasse für den Wald selbst verstärken und zeitlich weiterentwickeln. Es muss mit einer fortschreitenden Schwächung und Erwärmung des Dannenröder Forsts gerechnet werden. Neben den klimawandelbedingten Steigerungen von Extremtemperaturen kommt es durch die Rodung und Versiegelung von Waldbereichen, der Zerschneidung und einer damit zusammenhängenden Zunahme von Waldrandsituationen u.U. zu physiologisch kritischem Hitzestress. Die höheren Landschaftstemperaturen verstärken zudem die Verdunstung und in niederschlagsarmen Zeiten das Wasserdefizit. Damit muss ein deutlich negativer Einfluss auf den Landschaftswasserhaushalt postuliert werden. Die aus dieser Studie resultierenden Erkenntnisse sollten generell bei aktuellen und zukünftigen Infrastrukturplanungsprozessen berücksichtigt werden. In einer Zeit, in der vom Staat erhebliche finanzielle Mittel zur Bewältigung von bereits entstandenen Waldschäden und zur Wiederherstellung von Waldflächen bereitgestellt werden müssen und gleichzeitig versucht wird, durch Klimawandelanpassungsstrategien die Landnutzung zukunftsfähig zu machen und den Landschaftswasserhaushalt zu stabilisieren, erscheint es unverantwortlich, ökologisch wertvolle Waldrelikte zu zerschneiden und diese dadurch neuen Risiken auszusetzen. Angesichts der bislang ignorierten Gefahr, dass sich Wirkungen von Straßen auf Ökosysteme und den Landschaftswasserhaushalt mit dem Klimawandel verstärken können, wird empfohlen die Bundesverkehrswegeplanung diesbezüglich neu zu bewerten.
... Roads are the first stage of urban sprawl and the initial destabilizer of natural ecosystems. Maintaining connectivity at the landscape level is the main conservation action promoting resilience and structure for the protection of biodiversity (Selva et al., 2011). I finally state that -as roads hold such importance as natural process disruptors, the ecological benefits of areas with no roads ("roadless areas") are the primary concept to include in any permanent solution delivered for road developers and road ecologists hold such responsibility to address this need for future road mitigation (Selva et al., 2011). ...
... Maintaining connectivity at the landscape level is the main conservation action promoting resilience and structure for the protection of biodiversity (Selva et al., 2011). I finally state that -as roads hold such importance as natural process disruptors, the ecological benefits of areas with no roads ("roadless areas") are the primary concept to include in any permanent solution delivered for road developers and road ecologists hold such responsibility to address this need for future road mitigation (Selva et al., 2011). ...
With the increase in the transportation systems in the world, roads provide opportunities for human
social and economic development. Roads are also the primary cause of multiple and diverse
ecological negative effects. Habitat and wildlife populations are directly disturbed as roads
contribute to habitat loss, habitat fragmentation and reduction of the quality of surrounding
habitats. Barrier effects and traffic mortality are amongst the principal factors impacting
species that need to move among important habitats to complete their life cycle leading to
fragmentation, isolation and local population extinctions. Pond-breeding amphibians can be
particularly impacted in this way, with mortality rates of 60-90% imposed by roads in some
circumstances. Road mitigation measures, such as tunnels and associated fences, are
implemented to manage this problem and restore connectivity at the landscape level to sustain migration and dispersal movements for amphibians and maintain metapopulation
dynamics over the long term.
In the UK, the demand for the implementation of these mitigation infrastructures has increased
in the past decade as urban development reached a detrimental point for the European
Protected Species, Triturus cristatus, the Great Crested Newt. Road mitigation measures for
newt species are notoriously difficult to implement efficiently due to the behavioural
characteristics of this group and the poor understanding of how it influences road mitigation
effectiveness. Their ability to climb vertical surfaces, the poor capacity for crossing large
distances over land and general avoidance of small, narrow structures such as tunnels are
some examples of responses that may influence how planning and design of mitigation can
support and facilitate patterns of movements for the species. There is no clear understanding
of how these responses and patterns influence successful crossings and dispersal in the long term in the UK or the rest of Europe. Therefore, it is challenging to predict mitigation long term
effectiveness, provide evidence-based guidance to developers despite their substantial costs
and potentially crucial importance for maintaining connectivity and dispersal for this European
protected species.
The main aim of this study was to evaluate T. cristatus movement patterns in areas that impacted
by roads and at which road mitigation measures had been deployed in order to develop
evidence-based improvements for the strategic planning and design of dispersal corridors for
... Roadless regions represent relatively undisturbed ecosystems that make substantial contributions to maintaining biodiversity (Crist et al., 2005;Selva et al., 2015). Roadless areas adjacent to protected areas have the potential to increase the connectivity and size of parks, designated wilderness, and wildlife refuges (Crist et al., 2005), and even smaller isolated road-free regions can provide habitat for rare species, increase habitat variation, and facilitate movement of organisms between larger patches (Selva et al., 2011;Strittholt & Dellasala, 2001). Areas without roads are also more resilient than fragmented regions to the effects of climate change (Selva et al., 2011). ...
... Roadless areas adjacent to protected areas have the potential to increase the connectivity and size of parks, designated wilderness, and wildlife refuges (Crist et al., 2005), and even smaller isolated road-free regions can provide habitat for rare species, increase habitat variation, and facilitate movement of organisms between larger patches (Selva et al., 2011;Strittholt & Dellasala, 2001). Areas without roads are also more resilient than fragmented regions to the effects of climate change (Selva et al., 2011). Analysis of existing datasets has revealed that over 80% of the Earth's surface consists of roadless areas (at least 1 km from the nearest road), but these are fragmented into almost 600,000 patches, more than half of which are <1 km 2 (Ibisch et al., 2016). ...
Roads are an overwhelming component of the global human footprint and their absence helps identify intact areas with high ecological value. Road‐free areas are decreasing globally, making accurate estimation of their location and size of great importance. Identification of such regions requires accurate data, but substantial variability exists in road network datasets created and maintained at different spatial scales. We compared estimates of road length, density, and roadless areas across Canada, which contains a high proportion of the world's remaining undisturbed and road‐free areas. Global‐ and national‐scale datasets included, on average, only 11%–14% of roads represented in regional‐scale data or volunteered geographic information (VGI), with the most pronounced differences in less‐developed areas. Regional‐scale datasets, with the lowest estimates of amount of roadless area and smallest mean roadless patch size, are likely the most complete road datasets but are not available for all jurisdictions, limiting their national‐scale utility. VGI provides a national‐scale alternative but still lacks many low‐use roads. Available global and national datasets have insufficient information for accurate assessments of roadless areas in Canada, which will require detailed, consistent subnational datasets assembled and maintained by each province and territory in a coordinated fashion to achieve national coverage.
... Distribution of citations of the most relevant studies by year[2,[19][20][21][22][23][24][25][26][27]. ...
Road transport is one of the main contributors to increasing greenhouse gas (GHG) emis- sions, consequently aggravating global warming, but it is also one of the sectors that most suffer from climate change, which causes extreme weather events. Thus, strategies, also called adaptation measures, have been discussed to minimize the impacts of climate change on transport systems and their infrastructure; however, a knowledge gap is evident in the literature. Therefore, this article develops a systematic review with a bibliometric approach, still scarce in the literature, in renowned databases, focusing on studies developed on adaptation measures for road infrastructure. The results show that, since the development of the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC), an increasing amount of studies on the theme have been published in recognized journals such as Science of the Total Environment, Energy and Buildings and Urban Climate, analyzing climate threats such as intense precipitations and high temperatures that have led to biophysical impacts such as flooding and urban heat island. In addition, for each type of adverse weather condition, many impacts on road infrastructure can be listed, as well as ways to detect these impacts, and adaptation measures that can be used to minimize these problems.
... In Germany, roadless areas are indirectly included in conservation measures aiming to avoid fragmentation of large, mostly unfragmented landscapes by linear infrastructures and to minimize other ecological impacts (Federal Nature Conservation Act from 29 July 2009). In places where the road network encompasses most of the territory, as in many European countries, the concept of low-traffic areas is also used for legal purposes, representing places where the impact of road infrastructure is minimal (Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, 2009;Selva et al. 2011;Turner 2009). ...
Roadless areas (RLAs) are places with little to no influence of roads, usually sustaining well-preserved habitats, whereas road-effects zones (REZs) are areas affected by roads. Here, we map and characterize RLAs and REZs in Brazil, using national and international road network, land use and land cover, and protected areas databases. Following a global scale study, RLAs were defined as areas within ≥ 1 km from roads. Considering only paved roads, 8.2 M km2 (95%) of Brazil’s territory is RLAs, a figure that reduces to 6.8 M km2 (81%) when all built roads are included. In Brazil, the furthest location from roads is in the Amazon, 321 km away from the nearest road. Although RLAs differs among the Brazilian ecosystems, some common patterns emerge: (i) There is a lower percentage of natural vegetation cover on REZs than in RLAs, except for the Pampa; (ii) RLAs are mostly composed by natural vegetation, except in the Atlantic Forest, where farming lands dominate; (iii) protected RLAs are mostly covered by natural vegetation. Only 36.9% of Brazil’s RLAs are inside protected areas or indigenous lands. Even so, given the ongoing expansion of the road network and agriculture frontier in Brazil, it is unequivocal the role of those protected areas in stopping those drivers, making it paramount to explicitly include RLAs when planning new protected areas. Lastly, we found a positive relationship between a RLA patch size and its native vegetation cover as well as a positive relationship between the percentage of a protected area covered by RLA and its native vegetation cover.
... mainly because of its frequent thinning or other operations relying on a "good" road infrastructure, especially in steeper terrain, which appears crucial for implementation of close-to-nature forestry (Bauhus et al., 2013). Seeing that new forest roads are one of the major drivers of eagle's breeding disturbance, habitat alteration and loss (Meyburg et al., , 2004Treinys, 2004;Väli, 2003;Väli et al., 2004) with many adverseand often cumulative or cascadingeffects on climate, water, soil, plants, animals and landscapes (Forman and Alexander, 1998;Trombulak and Frissell, 2000;Gucinski et al., 2001;Coffin, 2007;Selva et al., 2011;Wosniack et al., 2013;Boston, 2016;Angelstam et al., 2017), this forestry approach is unlikely to comply with the eagle's or similar conservation objectives, particularly in national parks, protected landscape areas and SPAs such as Laborecká vrchovina Mts. In order to solve this serious but so far overlooked problem and inherent land-use conflicts by minimizing road density, a sustainable forest management as a part of integrated landscape management should be adopted (Lazdinis et al., 2019;Mann et al., 2018) across states, sectors, governance levels and contexts. ...
Habitat loss and fragmentation along with altered disturbance regimes cause raptor population declines, but processes, rates and interactions are seldom known. Knowledge gaps remain mainly in large forest-dwelling raptors that use habitats on several spatial scales. Our study focusses on breeding habitats and habitat-associated breeding performance of the Lesser Spotted Eagle (“eagle”) across five spatial scales in Laborecká vrchovina Mts (East Carpathians, Slovakia) during 2011–2016. We calculated two relative measures of breeding performance (breeding attempt index, BAI; nest productivity index, NPI) and related them to habitat characteristics sampled on the nest-platform, nest-tree, nest-site, home-range and landscape scale. We found that eagle‘s breeding performance was best explained by predictors on the home-range and landscape scale. BAI and NPI strongly and consistently increased with increasing distance of nest to the nearest felling site and with occurrence of the nest site on lower slope landforms. Former finding supported ample evidence that logging operations pose a grave threat to eagle’s reproduction, while the latter hinted at its strong preference or even specialization for forest edges, for notably old regional ecotones between montane forests and submontane non-forest formations show lower slope topography. On the nest-site scale, nest productivity (NPI) significantly and strongly increased with increasing percentage of Sessile Oak (Quercus petraea) and decreased with cosine of slope aspect in response to more open and accessible canopy structure resulting from oak appearance in beech-dominated forests and to contrasts in solar radiation, shade and similar north–south effects. On the nest-platform and nest-tree scale breeding performance marginally significantly increased with increasing relative nest height above ground and decreased in nests of natural origin (in BAI). It pointed to unrecognized relevance of relative nest height that may link nest-tree with nest-site scale and reflect a trade-off between nest accessibility and nest protective cover, and to greater nest placement diversity with possible greater vulnerability of natural nests. Differences in breeding performance measured by BAI vs NPI indicated that certain selection pressures may vary significantly during the breeding cycle, e.g., early vs late breeding failures and subsequent learning from negative experience. We recommended several management actions by our results, particularly to advance systematic eagle monitoring, to address multiple scales of its habitat use according to their relative importance, to increase the width of protection zones around nests and adopt new or strengthen existing landscape-scale measures and to follow sustainable forestry as a part of integrated landscape management instead of close-to-nature forestry.
... [9]. Ως εκ τούτου, οι ΑΦΠ έχουν λάβει παγκόσμιας αναγνώρισης και η ανάγκη διαφύλαξής τους τόσο ως καταφύγια βιοποικιλότητας όσο και ως ακέραια οικοσυστήματα υψηλής οικολογικής λειτουργικότητας έχει υπογραμμιστεί πολλές φορές [7,11,13,[18][19][20][21][22][23][24][25][26]. Πρόσφατα δε, σε αναφορά του Τμήματος Πολιτικής που του ανατέθηκε από την Επιτροπή Περιβάλλοντος, Δημόσιας Υγείας και Ασφάλειας των Τροφίμων (ENVI) του Ευρωπαϊκού Κοινοβουλίου, η διαφύλαξη των περιοχών χωρίς δρόμους αναγνωρίστηκε ως μέτρο για τον έλεγχο διάδοσης των ασθενειών όπως οι ζωονόσοι [27]. ...
Η επιστημονική έκθεση παρουσιάζει τον εθνικό χάρτη των περιοχών χωρίς δρόμους της Ελλάδας. Πρόκειται για 389 πολύγωνα που ονομάζονται Αδιατάρακτες Φυσικές Περιοχές (ΑΦΠ), έχουν έκταση άνω των 2 τ.χλμ έκαστο και δεν διατρέχονται από δρόμους.Επιπλέον ο χάρτης περιλαμβάνει 3518 νησιά άνευ δρόμων, ή Νησιωτικές Αδιατάρακτες Φυσικές Περιοχές (ΝΑΦΠ) ανεξαρτήτως μεγέθους. Το 93% των νησιών που αξιολογήθηκαν είναι ΝΑΦΠ. Συνολικά ο εθνικός χάρτης των περιοχών χωρίς δρόμους (ΑΦΠ+ΝΑΦΠ) αποτελείται από 3.907 περιοχές, η συνολική έκταση των οποίων αντιστοιχεί στο 6,18% της έκτασης της Ελλάδας.
Η έκθεση δίνει μια ανασκόπηση της αξίας των περιοχών χωρίς δρόμους με τη συναφή επιστημονική τεκμηρίωση σε παγκόσμιο, ευρωπαϊκό και εθνικό επίπεδο και μια σύντομη αναφορά για την άποψη της Ελληνικής κοινωνίας επί των ΑΦΠ.
Παρουσιάζει τη σύνδεση της πολιτικής προστασίας των περιοχών χωρίς δρόμους με τους στόχους βιώσιμης ανάπτυξης, το παγκόσμιο πλαίσιο για τη βιοποικιλότητα, την Ευρωπαϊκή στρατηγική για τη βιοποικιλότητα, το στόχο μηδενικής καθαρής δέσμευσης γης μέχρι το 2050, την Ευρωπαϊκή Σύμβαση του Τοπίου, και την Εθνική Στρατηγική για τη Βιοποικιλότητα. Παράλληλα παρουσιάζει το παρόν θεσμικό πλαίσιο των μέχρι σήμερα 6 Υπουργικών Αποφάσεων προστασίας των Περιοχών Άνευ Δρόμων και τη σημασία προστασίας των ΑΦΠ ως προς τα εθνικά σχέδια δράσης για το αγριόγιδο και την καφέ αρκούδα. Εν τέλει δίνει μια σύντομη ανασκόπηση για τη διεθνή τάση προστασίας των περιοχών χωρίς δρόμους στον κόσμο με αναφορά στη θεσμική προστασία τους στις Η.Π.Α.
Το κύριο μέρος της επιστημονικής έκθεσης είναι μια σειρά από 13 προτάσεις αξιοποίησης των αποτελεσμάτων της έρευνας στη χάραξη και εφαρμογή εθνικής περιβαλλοντικής πολιτικής, από τον ορισμό περιοχών αυστηρής προστασίας εντός του δικτύου Natura, έως τη θεσμική προτασία του τοπίου και τη βιώσιμη ανάπτυξη.
Η έκθεση παρήχθηκε από το Εργαστήριο Διατήρησης της Βιοποικιλότητας (BCL) του Τμήματος Βιολογικών Εφαρμογών & Τεχνολογιών του Πανεπιστημίου Ιωαννίνων, υπό τη χρηματοδότηση του Πράσινου Ταμείου.
Ο ιστοχώρος της προγράμματος για περισσότερες πληροφορίες είναι https://bc.lab.uoi.gr/el/research/projects/roadless/. Σχετικές ανακοινώσεις αναρτώνται στο https://www.facebook.com/BCL.Ioannina/
Roads can have significant negative impacts on wildlife. Fauna-sensitive road design (FSRD) can alleviate adverse impacts on several species by installing specialised structures, such as wildlife crossing structures. This developing subfield has generally, however, had a limited impact on transportation planning and management. Indeed, most research is focused narrowly on technological solutions, instead of broader policy learnings. This systematic quantitative literature review (SQLR) of international literature sought to identify the biodiversity concerns acknowledged in transport planning policy, as well as the barriers to the adoption of environmental policies within transport planning. Despite considerable literature available on the impacts of roads on wildlife elsewhere, acknowledgement and consideration of both fauna movement and fauna-sensitive road design were limited in road transportation planning research. More broadly, failure to achieve environmental objectives within transport planning occurred primarily as a result of competing sector interests (conflicted knowledge), different political objectives (political interest), and incorrect interpretation of policies. In essence, the results add new layers of understanding to the field of transportation planning and policy, in particular, the gaps in acknowledgement of wildlife movements and the limitations of current fauna-sensitive road design considered. Importantly, the review identified multiple ecological support tools available to transport policy- and decision-makers. Integration of these in road transportation projects could facilitate enhanced uptake and adoption of FSRD measures and thus foster improved sustainability of the transport network.
We attempted a complete review of the empirical literature on effects of roads and traffic on animal abundance and distribution. We found 79 studies, with results for 131 species and 30 species groups. Overall, the number of documented negative effects of roads on animal abundance outnumbered the number of positive effects by a factor of 5; 114 responses were negative, 22 were positive, and 56 showed no effect. Amphibians and reptiles tended to show negative effects. Birds showed mainly negative or no effects, with a few positive effects for some small birds and for vultures. Small mammals generally showed either positive effects or no effect, mid-sized mammals showed either negative effects or no effect, and large mammals showed predominantly negative effects. We synthesized this information, along with information on species attributes, to develop a set of predictions of the conditions that lead to negative or positive effects or no effect of roads on animal abundance. Four species types are predicted to respond negatively to roads: (i) species that are attracted to roads and are unable to avoid individual cars; (ii) species with large movement ranges, low reproductive rates, and low natural densities; and (iii and iv) small animals whose populations are not limited by road-affected predators and either (a) avoid habitat near roads due to traffic disturbance or (b) show no avoidance of roads or traffic disturbance and are unable to avoid oncoming cars. Two species types are predicted to respond positively to roads: (i) species that are attracted to roads for an important resource (e.g., food) and are able to avoid oncoming cars, and (ii) species that do not avoid traffic disturbance but do avoid roads, and whose main predators show negative population-level responses to roads. Other conditions lead to weak or non-existent effects of roads and traffic on animal abundance. We identify areas where further research is needed, but we also argue that the evidence for population- level effects of roads and traffic is already strong enough to merit routine consideration of mitigation of these effects in all road construction and maintenance projects.
We attempted a complete review of the empirical literature on effects of roads and traffic on animal abundance and distribution. We found 79 studies, with results for 131 species and 30 species groups. Overall, the number of documented negative effects of roads on animal abundance outnumbered the number of positive effects by a factor of 5; 114 responses were negative, 22 were positive, and 56 showed no effect. Amphibians and reptiles tended to show negative effects. Birds showed mainly negative or no effects, with a few positive effects for some small birds and for vultures. Small mammals generally showed either positive effects or no effect, mid-sized mammals showed either negative effects or no effect, and large mammals showed predominantly negative effects. We synthesized this information, along with information on species attributes, to develop a set of predictions of the conditions that lead to negative or positive effects or no effect of roads on animal abundance. Four species types are predicted to respond negatively to roads: (i) species that are attracted to roads and are unable to avoid individual cars; (ii) species with large movement ranges, low reproductive rates, and low natural densities; and (iii and iv) small animals whose populations are not limited by road-affected predators and either (a) avoid habitat near roads due to traffic disturbance or (b) show no avoidance of roads or traffic disturbance and are unable to avoid oncoming cars. Two species types are predicted to respond positively to roads: (i) species that are attracted to roads for an important resource (e.g., food) and are able to avoid oncoming cars, and (ii) species that do not avoid traffic disturbance but do avoid roads, and whose main predators show negative population-level responses to roads. Other conditions lead to weak or non-existent effects of roads and traffic on animal abundance. We identify areas where further research is needed, but we also argue that the evidence for population-level effects of roads and traffic is already strong enough to merit routine consideration of mitigation of these effects in all road construction and maintenance projects.
A steady growth in traffic volumes in industrialized countries with dense human populations is expected, especially on minor roads. As a consequence, the fragmentation of wildlife populations will increase dramatically. In human-dominated landscapes, typically minor roads occur in high densities, and animals encounter them frequently. Traffic calming is a new approach to mitigate negative impacts by reducing traffic volumes and speeds on minor roads at a regional scale. This leads to a distinction between roads with low volumes as being part of the traffic-calmed area, whereas roads with bundled traffic are located around this area. Within the traffic-calmed area, volumes and speeds can be decreased substantially; this is predicted to decrease the disturbance and mortality risk for animals. Thus far, data on the effects of traffic calming on wildlife population persistence remain scarce. Using metapopulation theory, we derived a model to estimate thresholds in the size of traffic-calmed areas and traffic volumes that may allow persistent populations. Our model suggests that traffic calming largely increases the persistence of roe deer in a landscape with a dense road network. Our modeling results show trade-offs between traffic volume on roads within the traffic-calmed area and both the area of habitat available for this species in the traffic-calmed area and the size of the traffic-calmed area. These results suggest ways to mitigate the fragmentation of wildlife habitat by road networks and their expected traffic volumes
Abstract A huge road network with vehicles ramifies across the land, representing a surprising frontier of ecology. Species-rich roadsides are conduits for few species. Roadkills are a premier mortality source, yet except for local spots, rates rarely limit population size. Road avoidance, especially due to traffic noise, has a greater ecological impact. The still-more-important barrier effect subdivides populations, with demographic and probably genetic consequences. Road networks crossing landscapes cause local hydrologic and erosion effects, whereas stream networks and distant valleys receive major peak-flow and sediment impacts. Chemical effects mainly occur near roads. Road networks interrupt horizontal ecological flows, alter landscape spatial pattern, and therefore inhibit important interior species. Thus, road density and network structure are informative landscape ecology assays. Australia has huge road-reserve networks of native vegetation, whereas the Dutch have tunnels and overpasses perforating road barriers to enhance ecological flows. Based on road-effect zones, an estimated 15–20% of the United States is ecologically impacted by roads.
Ecological impacts from roads may be the rule rather than the exception in most of the conterminous United States. We measured the proportion of land area that was located within nine distances from the nearest road of any type, and mapped the results for 164 ecoregions and 2108 watersheds nationwide. Overall, 20% of the total land area was within 127 m of a road, and the proportion increased rapidly with distance, so that 83% was within 1061 m of a road, and only 3% was more than 5176 m away. For forest land area only, the proportions differed by less than 2% for all distances. Regions with more than 60% of their total land area within 382 m of a road may be at greatest risk of cumulative ecological impacts from roads. These regions include nearly all coastal zones, as well as substantial portions of the southeast US and the basins of the Ohio, Brazos, Colorado, Sacramento, and San Joaquin Rivers.
