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1.
Aušrinė Armaitienė Vadim L. Boldyrev Ramūnas Povilanskas Julius Taminskas 《Journal of Coastal Conservation》2007,11(1):13-22
The varied and very dynamic landscape with a high biological diversity is a distinctive feature of the Curonian spit at the
regional scale. Throughout the 20th century the main morphodynamic trend in the littoral of the Curonian spit was shoreline
grading on the lagoon side, whereas on the marine side the increasing erosion at the foot of the spit, and increasing accretion
at the head of the spit prevailed. The results of a discriminant analysis (Wilkes’ λ = 0.001626 and F = 29.267 when p < 0.001) show that sites with prevailing erosion, accretion and sediment input from the drifting dunes form regular inter-related
spatial structures in the littoral with distinctive resulting discontinuities of the sediment drift along the lagoon coast.
Dune littoral cells are characterized by Aeolian sediment input and distribution ‘down-drift’, (usually northwards) from the
source. The most likely changes in the current development trends of the lagoon shore zone of the Curonian spit are related
to expected climate changes and further slowing down of the dune drift. The probability of storms and ice-drift events, and
their impact on coasts is expected to increase as a result of climate change. The dune advance will gradually slow down, and
with it, the sand input to the coastal zone will decline. In this paper, we define integrated shoreline management as a system
of long-term shoreline management measures, which is based on a littoral cell approach and aimed at harmonizing human activity
in the coastal zone with the natural development of the shoreline. We propose an integrated management program for the lagoon
shoreline of the Curonian spit, which is site-specific for each littoral cell as a coastal management unit. Drifting dunes
and seaside beaches are the natural amenities, which are best known and best appreciated on the Curonian spit by 49% of the
respondents representing the total Lithuanian population. A responsible tourism development should be considered as the key
means for proper appreciation of the drifting dunes and natural coasts by society, which means to acknowledge and cherish
the aesthetic and conservation values of dune and coastal landscapes of the Curonian spit as a World Heritage Site. There
are at least two pre-conditions for this: (1) to provide visitors with sufficient information about diverse values and functions
of the Curonian dunes and coasts within a broader regional and global heritage conservation context; (2) to enable tourists
to enjoy the most impressive dune and coastal landscapes at close range. In this paper we propose to encourage active dune
tourism, to reintroduce grazing into the Curonian dune areas, to restore and to preserve the most impressive landscapes of
the highest white drifting dunes by bringing the blown out sand from the leeward foot of the dunes back to the crest artificially. 相似文献
2.
Sam Provoost Carole Ampe Dries Bonte Eric Cosyns Maurice Hoffmann 《Journal of Coastal Conservation》2004,10(1):33-42
Grey dunes are a priority habitat type of the European Union Habitats Directive and demand special attention for conservation
and management. Knowledge of the ecology of coastal grey dunes can contribute to this policy. Dune grassland succession is
initiated by fixation and driven by the complex of soil formation (humus accumulation) and vegetation development. Leaching
and mobilization of CaCO3. which are important in nutrient dynamics, complicate the picture. At present, grass- and scrub encroachment greatly overrules
these fine scaled soil processes and causes substantial loss of regional biodiversity. Belgium has an international responsibility
in grey dune conservation because of the limited range of its characteristic vegetation, flora and fauna. As biomass removal
seems essential in grassland preservation, grazing is an important management tool. Evaluation of management measures focuses
on biodiversity measurements on the levels of landscape, community and species. 相似文献
3.
Topography and vegetation of restored dunes on a developed barrier island were examined after a large-scale beach nourishment
project. Restoration began in 1993 using sand-trapping fences andAmmophila breviligulata Fern. plantings. Subsequent growth of dunes was favored by installing new fences and suspending beach raking to accommodate
nesting birds. Plant species richness, percent cover of vegetation, and height ofA. breviligulata were sampled in 1999 on seven shore perpendicular transects in six dune microhabitats (backdune, primary crest, mid-foredune,
swale, seaward-most fenced ridge, incipient dune on the backbeach).
A total of 26 plant taxa were found at all seven sites. Richness and percent cover were greatest in the backdune and crest,
especially in locations that predated the 1992 nourishment. Richness was greater where fences enhanced stabilization. Fences
initially compensate for time and space and allow vegetation to develop rapidly, but maintenance nourishment is required to
protect against wave erosion and ensure long-term viability of habitat. An expanded environmental gradient is an option, where
beach nourishment provides space for a species-rich crest and backdune to develop, while the incipient dune remains dynamic.
Options where space is restricted include a dynamic, full-sized seaward section of a naturally functioning dune (truncated
gradient) or a spatially restricted sampler of a wider natural dune (compressed gradient) maintained using fences. Expanded
and truncated gradients may become self-sustaining and provide examples of natural cycles of change. Compressed gradients
provide greater species richness and flood protection for the available space, but habitats are vulnerable to erosion, and
resident views may be impaired. 相似文献
4.
Successful migration for passerine birds depends largely on the quality of stopover habitats, but we still lack complete knowledge
of how migrants search for habitats en route and how they behave when landing at poor quality stopover sites. We compared
the distance of exploratory movements and stopover durations of the reed warbler Acrocephalus scirpaceus, a reedbed habitat specialist, released at suitable (reed bed) and unsuitable (sand dune) stopover sites. Birds tape-lured
during nocturnal migration to a sand dune were captured, radio-tagged, released and tracked at two sites of contrasting habitat
quality. Lean birds were found to move further in the dunes (max. 300 m) than in reeds (max. 200 m), whereas ‘fat’ individuals
at both sites remained stationary. Birds spent just 1 day in the dunes and up to 13 days in the reeds. Our results suggest
that some nocturnal migrants with restricted diurnal exploratory movements depend on stopover site selection when ceasing
nocturnal flight. 相似文献
5.
Soil microarthropods (Acari, Collembola) were analyzed along transects from shore to brown dune in two sandy coastal sites
of the North Sea (Jutland, Denmark, and Spiekeroog, East Frisian island, Germany). Predatory mites (Acari: Gamasina) and Collembola
were determined to species. The Jutland and the Spiekeroog sites each yielded 22 Gamasina species, 10 of which are common
to both areas. Collembola were identified from the Spiekeroog samples only (also 22 species).
Largest mite abundances were found in Jutland in primary dunes (419 tsd. ind./m2) and on Spiekeroog in old brown dunes (314 tsd.ind./m2). Compared to the mites, Collembola abundances are low, with maxima of 77 tsd.ind./m2 in Jutland (yellow dune) and only 18 tsd. ind./m2 on Spiekeroog (old vellow dune).
The communities of predatory mites (Gamasina) and Collembola along transects from shore inland to brown dune are quite specific.
High similarities are found for the predatory mites between the specific dune sites of the two North Sea areas, particularly
for yellow dune.
Additionally, preliminary data are presented for the southern Baltic Coast. The findigns are discussed in a broader context.
Arguments focus on conservation and biogenic dune stabilization. 相似文献
6.
The impact of grazing on spider communities in a mesophytic calcareous dune grassland 总被引:1,自引:0,他引:1
During 1994–1995 and 1997–1998 spiders were sampled with pitfall traps in a botanically rich, mesophytic, calcareous dune
grassland in Belgium. As a consequence of intensive cattle grazing, vegetation variation in a large part of the area had diminished.
The study area was also patchily grazed by rabbits. Community analysis with TWINSPAN revealed five distinct spider communities.
Ecological differentiation was best explained by combination of the habitat variables: distance from grazed or non-grazed
vegetation,Rosa pimpinellifolia cover and grass cover in both summer and winter. Species diversity was highest in the border zone between the cattle-grazed
and non cattle-grazed sites.
Correlation of the most abundant spider species with the vegetation determinants explains the ecological differentiation between
the spider communities. Species were classified into seven major groups that reflect the species’ habitat preferences. The
group showing clear association with non cattle-grazed, tall vegetation consists of common species. Characteristic species
for the intensively cattle-grazed sites are common aeronauts and rare species such asWalckenaeria stylifrons, Mastigusa arietina, Ceratinopsis romana andPardosa monticola. The latter are shown to be dependent on ungrazed vegetation for juvenile development and overwintering. Intensive grazing
results in homogeneous short vegetation, which can only be colonized by ‘open ground’ species with a well-developed dispersal
capacity, or by species which are not dependent on litter-rich situations for juvenile development. An extensive cattle grazing
regime results in a patchy mosaic grassland where, in addition to the above mentioned groups of species, other species survive
by migrating between the buffered litter rich ungrazed vegetation and the short vegetation. Additionally, some typical and
rare species prefer the transition zone between the grazed and the ungrazed vegetation because they are associated with specific
habitat structures or inhabiting ant-species. 相似文献
7.
Although most UK sand dune systems are now fossilized, with little mobility and reducing amounts of bare sand, they support
important populations and assemblages of terrestrial invertebrates. Offering open conditions, warm substrates and a range
of habitats and habitat structures, they have become increasingly significant as other coastal habitats have been lost. In
Wales, 680 Red Data Book and Nationally Scarce species have been recorded from dunes. 109 species in the UK are restricted
to dunes, and in Wales there are an additional 145 species confined to dunes and 208 species strongly associated with dunes.
Of these, 172 species are dependent upon bare and sparsely-vegetated sand, in grey dunes and early-successional dune grassland,
at some stage of their life cycle, rising to 292 species if those associated with the strandline, foredunes, yellow dunes
and pioneer dune slacks are included, equating to 63% of the 462 dune species. Bees and wasps are particularly well represented,
with 278 species (68% of the Welsh fauna) recorded on Welsh dunes, including 17 obligates and 44 species with a strong dependence,
52 of which are associated with bare and sparsely-vegetated sand. Key to maintaining invertebrate populations on UK dunes
is the provision of bare sand but in Wales, bare sand accounts for only 1.7% of the total sand dune resource. As a more appropriate
bare sand threshold is likely to range between 10 and 30%, radical action is required to re-mobilize at least the key sand
dune systems. 相似文献
8.
Annelore Bezzi Simone Pillon Davide Martinucci Giorgio Fontolan 《Journal of Coastal Conservation》2018,22(3):503-518
Management of coastal dunes on developed coasts could effectively take advantage of comprehensive and multitemporal georeferenced data collection, which offers the possibility to relate dune data with the natural and cultural characteristics of the beach and hinterland. The recent implementation of a coastal management geodatabase for the Veneto region provides the opportunity for improving knowledge on coastal dunes on developed littoral as well as a basis for appropriate future coastal planning in the study area. The geodatabase gathers data concerning different physical, evolutionary and human aspects of the coastal zone, with a special focus on coastal dunes. Established foredunes, human-altered dunes and relict dunes are irregularly distributed along 59 km, 38% of the entire coastal length. Their distribution and characteristics are the result of favourable natural conditions as well as long-lasting tourism exploitation (evaluated through an index of Land Use Pressure) and fragmentary and diversified uses of beaches (evaluated through an index of Tourism Pressure on the beach). At the same time, beach/dune nourishment intervention allowed the presence of artificial or sand fenced dunes along 17 km of coast. High dune elevation up to 8–10 m is promoted by the onshore exposition of the beach to dominant wind (from ENE), by stable-to-slowly negative sedimentary budget or by the re-activation of high relict foredunes in the case of shoreline retreat associated with strong negative budget. Present sedimentary budget (evaluated through the code ASPE – Accretion, Stable, Precarious, Erosive) is the tool used for dividing coasts in sedimentary compartments or cells. Past and present sedimentary budget and different human responses to erosive cases (hard and soft interventions) give the foredunes different means to form, grow, survive and evolve over time. The assessment of Human Impact and Active Management Practices on the dunes allows a first evaluation of the Management Effectiveness, which shows strong shortcomings for 81% of the dunes. The great variability of beach usage, human impact and management practises on the different dune stretches highlight the lack of effective and systematic management actions being correctly scheduled and performed. 相似文献
9.
During 1994–1995 and 1997–1998 spiders were sampled with pitfall traps in a botanically rich, mesophytic, calcareous dune
grassland in Belgium. As a consequence of intensive cattle grazing, vegetation variation in a large part of the area had diminished.
The study area was also patchily grazed by rabbits. Community analysis with TWINSPAN revealed five distinct spider communities.
Ecological differentiation was best explained by combination of the habitat variables: distance from grazed or non-grazed
vegetation,Rosa pimpinellifolia cover and grass cover in both summer and winter. Species diversity was highest in the border zone between the cattle-grazed
and non cattle-grazed sites.
Correlation of the most abundant spider species with the vegetation determinants explains the ecological differentiation between
the spider communities. Species were classified into seven major groups that reflect the species’ habitat preferences. The
group showing clear association with non cattle-grazed, tall vegetation consists of common species. Characteristic species
for the intensively cattle-grazed sites are common aeronauts and rare species such asWalckenaeria stylifrons, Mastigusa arietina, Ceratinopsis romana andPardosa monticola. The latter are shown to be dependent on ungrazed vegetation for juvenile development and overwintering. Intensive grazing
results in homogeneous short vegetation, which can only be colonized by ‘open ground’ species with a well-developed dispersal
capacity, or by species which are not dependent on litter-rich situations for juvenile development. An extensive cattle grazing
regime results in a patchy mosaic grassland where, in addition to the above mentioned groups of species, other species survive
by migrating between the buffered litter rich ungrazed vegetation and the short vegetation. Additionally, some typical and
rare species prefer the transition zone between the grazed and the ungrazed vegetation because they are associated with specific
habitat structures or inhabiting ant-species.
Nomenclature: Roberts (1987, 1995) forAraneae; van der Meijden et al. (1990) for vascular plants; Corly et al. (1981) for bryophytes; Schaminée et al. (1996) for vegetation
associations. 相似文献
10.
Linking irreplaceable landforms in a self‐organizing landscape to sensitivity of population vital rates for an ecological specialist
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Wade A. Ryberg Michael T. Hill Charles W. Painter Lee A. Fitzgerald 《Conservation biology》2015,29(3):888-898
Irreplaceable, self‐organizing landforms and the endemic and ecologically specialized biodiversity they support are threatened globally by anthropogenic disturbances. Although the outcome of disrupting landforms is somewhat understood, little information exists that documents population consequences of landform disturbance on endemic biodiversity. Conservation strategies for species dependent upon landforms have been difficult to devise because they require understanding complex feedbacks that create and maintain landforms and the consequences of landform configuration on demography of species. We characterized and quantified links between landform configuration and demography of an ecological specialist, the dunes sagebrush lizard (Sceloporus arenicolus), which occurs only in blowouts (i.e., wind‐blown sandy depressions) of Shinnery oak (Quercus havardii) sand‐dune landforms. We used matrix models to estimate vital rates from a multisite mark‐recapture study of 6 populations occupying landforms with different spatial configurations. Sensitivity and elasticity analyses demonstrated demographic rates among populations varied in sensitivity to different landform configurations. Specifically, significant relationships between blowout shape complexity and vital rate elasticities suggested direct links between S. arenicolus demography and amount of edge in Shinnery oak sand‐dune landforms. These landforms are irreplaceable, based on permanent transition of disturbed areas to alternative grassland ecosystem states. Additionally, complex feedbacks between wind, sand, and Shinnery oak maintain this landform, indicating restoration through land management practices is unlikely. Our findings that S. arenicolus population dynamics depended on landform configuration suggest that failure to consider processes of landform organization and their effects on species’ population dynamics may lead to incorrect inferences about threats to endemic species and ineffective habitat management for threatened or endangered species. As such, successful conservation of these systems and the biodiversity they support must be informed by research linking process‐oriented studies of self‐organized landforms with studies of movement, behavior, and demography of species that dwell in them. 相似文献
11.
Coastal dunes are an essential part of beach-dune systems. Dunes systems have their own intrinsic values and provide a range of goods and services, including the protection of tangible goods located on the shoreline affected by waves, storms, and sea erosion. Dunes also act as repositories of biodiversity that have their exclusive habitat in dune communities, and the aesthetic value of dune landscapes derived from unique plant communities and landforms is also of great importance. Nevertheless, dune systems on developed coasts suffered a drastic decline in geomorphological and ecological quality throughout the last century. Catalonia (Spain, NW Mediterranean Sea) is no exception, and the coastal dune systems which were present in the early 20th century have now disappeared due to urbanization. The regeneration of dune systems is of crucial importance in this context. The aim of this study is to assess the current status of dune systems in Catalonia in order to determine their future prospects based on beach characteristics, those beaches likely to host dunes being determined according to their width and sediment type. The results of our study show that nowadays most dune systems in Catalonia are not developed due to human pressure on the beaches. Only those beaches located in the natural protected areas in Roses Bay, Baix Ter Bay, the Llobregat Delta, and especially the Ebro Delta, have the right characteristics to host well-developed dune systems. That said, 30% of sandy beaches in Catalonia have a width of over 35 metres; wide enough to host well-developed dune systems if appropriate integrated beach management is applied. The methodology used in this research also provide a tool to assess which are the beaches that can host dunes on other developed shores in the Mediterranean area. 相似文献
12.
The coastline near the southern tip of Africa is characterized by large mobile dunes that are driven along wide beaches by
strong winds throughout the year. This results in the blockage of the river mouths causing severe flooding of the low-lying
farmland of the Agulhas Plain during the rainy winter season. Large parts of the driftsands were stabilized with the European
dune pioneer species Marram grass (Ammophila arenaria), which has proved highly invasive along the North American west coast. In order to establish the potential invasiveness
ofA. arenaria in South African coastal dune systems and its role in the succession of a large stabilization area, studies were carried
out on De Mond Nature Reverve. Using aerial photos, maps and planting records, the vegetation of sites of various ages were
sampled. By means of this chronosequence of stands, there is clear evidence that succession takes place at De Mond. Four communities
are distinguished, varying from recent plantings ofA. arenaria to mature dune thicket or dune fynbos (heath) vegetation. These relate to four different stages of succession,A. arenaria occurring in reduced abundance in the older communities. After 50 years, formerA. arenaria areas are usually covered by dense dune scrub and in some places even in asteraceous dune fynbos. Succession is most rapid
in sheltered, moist dune slacks, butA. arenaria remains vigorous in conditions favourable for its growht, i.e. on exposed, steep dune slopes with strong sand movement.A. arenaria does not appear to spread unaidedly at De Mond and has been successfully used for temporary dune stabilization. 相似文献
13.
This paper examines the influence of dune morphological evolution on plant species diversity and composition on the Magheramore
dune system, Donegal, north-west Ireland. It aims to demonstrate the need for understanding of local geomorphological factors
and their affect on ecological processes for the enhanced conservation management of coastal dunes. Vegetation surveys and
cluster analysis of species associations, in combination with GIS analysis focused on two prograding dune sites within the
Magheramore system. Contrasting geomorphic evolution over similar timescales has imposed site-specific environmental conditions
that have had a direct impact on the range of plant species communities present. Cluster analysis revealed 5 main species
community types that defined specific dune habitats, the organisation of which is strongly influenced by geomorphic evolution.
This study demonstrates the importance of geomorphic evolution and morphological heterogeneity in habitat and species diversity. 相似文献
14.
C. Soulsby D. Hannah R. Malcolm J. K. Maizels R. Gard 《Journal of Coastal Conservation》1997,3(2):143-154
This paper reports the results of 12 years of hydrological monitoring at the St. Fergus dune system in northeastern Scotland.
The site is adjacent to the UK’s largest gas terminal and the dunes are crossed in five places by North Sea gas pipelines
which were constructed between 1976 and 1990. These are buried beneath the dune system which was restored after pipeline installation.
The dunes include a substantial freshwater wetland which is seasonally flooded and provides an important habitat for waterfowl.
The hydrogeology of the site is characterized and the hydrogeological processes that sustain this wetland feature are considered
including recent climatic fluctuations.
Nomenclature: Names of vascular plants follow Clapham et al. (1962). 相似文献
15.
The machair sand dune systems of the Outer Hebrides of Scotland are a unique habitat, which is rare within both a global and
European context. Unusually, the machair habitat also represents an agricultural resource that is very important to the Hebridean
people, having been subject to both grazing and cultivation throughout the historical period. Following designation as an
Environmentally Sensitive Area (ESA) in 1988, the machairs of South Uist have been studied with the aim of understanding the
links between agricultural practice and their plant community and ecosystem dynamics. This research focused primarily on the
effects of cultivation practices and their role in maintaining plant species richness and community and ecosystem stability.
Within two carefully selected areas, the successional plant communities of machair at different stages of recovery following
ploughing and cultivation of cereals and potato patches or ‘lazy beds’ were identified at both a macro- and micro-level. Investigations
of the vegetation recovery processes on turves taken from newly ploughed land indicated that the initial stages of recolonization
are characterized primarily by rapid vegetative reproduction and growth, although re-vegetation by seeds is also an important
factor. The implications of these findings for the long-term management of machair plant communities are discussed and in
particular the need to maintain old cultivation practices such as shallow ploughing. The need for more detailed research into
both seed banks and seed rain and into processes of vegetative reproduction is stressed.
Nomenclature: Clapham et al. (1981) and Stace (1991, 1997) for vascular plants; Hubbard (1984) for grasses; Pankhurst & Mullin (1991) for
the regional flora; Dobson (1992) for lichens; Watson (1981) for mosses and liverworts. 相似文献
16.
As coastal populations expand, demands for recreational opportunities on beaches and coastal dunes grow correspondingly. Although
dunes are known to be sensitive to direct human disturbance and provide irreplaceable ecosystem services (e.g. erosion control,
critical habitat and nesting sites), dunes serve as campsites for large numbers of people (∼90,000 p.a.) on the ocean-exposed
shores of Fraser Island, Australia. Campsites are located in the established dunes and can only be accessed with 4WD vehicles
along tracks cut directly from the beach through the foredunes. Here we quantified the extent of physical damage to foredunes
caused by this practice, and tested whether human-induced physical changes to foredunes translate into biological effects.
Of the 124 km of ocean-exposed beaches, 122 km (98%) are open to vehicles driven on the beaches, and camping zones cover 28.7
km or 23% of the dunes. A total of 235 vehicle tracks are cut across the foredunes at an average density of eight tracks per
km of beach. These tracks have effectively destroyed one-fifth (20.2%) of the dune front in camping zones, deeply incising
the dune-beach interface. There is evidence of accelerated erosion and shoreline retreat centred around vehicle tracks, resulting
in a “scalloping” of the shoreline. No dune vegetation remains in the tracks and the abundance of ghost crabs (Ocypode spp.) is significantly reduced compared with the abutting dunes. Because current levels of environmental change caused by
dune camping may not be compatible with the sustainable use of coastal resources and conservation obligations for the island
(listed as a World Heritage Area and gazetted as a National Park), restoration and mitigation interventions are critical.
These will require spatial prioritisation of effort, and we present a multi-criteria ranking method, based on quantitative
measures of environmental damage and ecological attributes, to objectively target rehabilitation and conservation measures.
Ultimately, coastal management needs to develop and implement strategies that reconcile demands for human recreation, including
beach camping, with conservation of coastal dune ecosystems. 相似文献
17.
This study reports the results of restoration management on sand dune environments along the coastal belt of the Castelporziano
nature reserve (Rome, Italy) and the subsequent monitoring phases to test the sustainability of the ‘soft techniques’ applied.
In the area concerned, over a length of ca. 3 km, 40 dunes were built up along with three belts located at <40 m, 40–70 m,
and >70 m, respectively, from the shoreline. On each of 38 dunes 20 individuals ofAmmophila littoralis were planted; this species is one of the local autochthonous species considered particularly suitable for stabilizing sand
dunes. After one year, two years and five years, respectively the changes in height and surface of each dune, the survival
rates ofA. littoralis, and its changes in cover, the appearance of new shoots and the establishment of new species were observed. A progressive
increase in species number, which five years after the restoration amounted to about 60% of those characterizing the natural
dunes, was reported indicating a progressive trend towards populations similar to natural ones. In the colonization of new
species there is a prevalence of theSporobolus-Elymetum farcti and theSalsolo Kali-Cakiletum maritimae association, while the species established successively refer to theEchinophoro spinosae-Ammophiletum arundinaceae association and theCrucianellion maritimae alliance as occurring in natural successions.
This succession runs parallel to the natural dune colonization processes. In particular, the data regarding survival, cover
and number of vegetative shoots indicate that the dune belt between 40 and 70 m from the sea is the one most suitable for
restoration.
Some changes in dune morphology was observed: the height of the artificial dunes tended to decrease considerably in the five
years of observation, whereas a progressive increase in their surface area was observed. During the study period.A littoralis favoured the establishment of new species, but as yet exercises no action on increasing dune height. 相似文献
18.
Frank van der Meulen Bert van der Valk Laurens Baars Eduard Schoor Hans van Woerden 《Journal of Coastal Conservation》2014,18(5):505-513
A new dune area was constructed by beach and foreshore nourishments along the Delfland Coast in the southwestern Netherlands. The new area is intended to be a compensation for losses of existing high quality dunes in nearby areas, due to the use/construction of Maasvlakte 2, the new harbour extension of Rotterdam opening in 2013. The target habitats for compensation include dry grey dunes and moist dune valley grassland. Due to the habitat type, the nourished material had to have a special character. The nourishment was carried out according to a special design and initial development of the new area had to follow certain pathways. In order to meet the compensation requirements in time. Careful monitoring is done to assess whether development of the new habitat is taking place in the direction of the desired target habitats. This paper reports on the construction of the new area and on the first years of development and monitoring. The monitoring mainly concerns development of the abiotic landscape elements, geomorphology, groundwater and soils. The lessons learned from this area are discussed in the light of the development of other recent young nature areas in the sandy Dutch delta coast. This gives new insights for coastal management in general in the context of building with nature. 相似文献
19.
The machair sand dune systems of the Outer Hebrides of Scotland are a unique habitat, which is rare within both a global and
European context. Unusually, the machair habitat also represents an agricultural resource that is very important to the Hebridean
people, having been subject to both grazing and cultivation throughout the historical period. Following designation as an
Environmentally Sensitive Area (ESA) in 1988, the machairs of South Uist have been studied with the aim of understanding the
links between agricultural practice and their plant community and ecosystem dynamics. This research focused primarily on the
effects of cultivation practices and their role in maintaining plant species richness and community and ecosystem stability.
Within two carefully selected areas, the successional plant communities of machair at different stages of recovery following
ploughing and cultivation of cereals and potato patches or ‘lazy beds’ were identified at both a macro- and micro-level. Investigations
of the vegetation recovery processes on turves taken from newly ploughed land indicated that the initial stages of recolonization
are characterized primarily by rapid vegetative reproduction and growth, although re-vegetation by seeds is also an important
factor. The implications of these findings for the long-term management of machair plant communities are discussed and in
particular the need to maintain old cultivation practices such as shallow ploughing. The need for more detailed research into
both seed banks and seed rain and into processes of vegetative reproduction is stressed. 相似文献
20.
A short outline is given of the floristic composition, structure and distribution of coastal dune vegetation found at Malindi
Bay, Kenya. The area was studied by air photo interpretation and field sampling to determine the relationship of plants to
aeolian features. TWINSPAN classification was used to distinguish geomorphological units on the basis of their species composition.
In this paper, an inventory and first quantitative analysis of vegetation distribution is presented. We identified 174 plant
species from 62 families in the sand dunes and several plant communities are distinguished based on the species content and
the connection with morphological units.Papilionaceae with 18 species andPoaceae with 17 species were the most represented families. A distinct zonal distribution of the plant communities was found.
The most important plant species are the pioneer vegetation consisting ofHalopyrum mucronatum, Ipomoea pescaprae andScaevola plumieri. The woody shrub species which have colonized the established primary dunes and hummock dunes areCordia somaliensis, Pluchea discoridis, Tephrosia purpurea (dunensis). Succulent herbs were identified in the dune slacks and salt marsh that are moist and damp environments. 相似文献