Settlement Site Selection Research Articles

Editorial Expression of Concern: Predation risk assessment by larval reef fishes during settlement-site selection

Editorial Expression of Concern: Predation risk assessment by larval reef fishes during settlement-site selection

Spatial Morphology Evolution of Rural Settlements in the Lower Yellow River Plain: The Case of Menggang Town in Changyuan City, China

This study investigated the spatial pattern evolution of the rural settlement system in the town of Menggang, China, based on settlement patches extracted from remote sensing data for four time points between 1990 and 2018. Five typical villages were selected to study their spatial textures from point to surface. The reasons for the evolution of the rural settlements were examined as well. The results indicated that the number of settlement patches in Menggang decreased, the area of a single patch expanded, and the scale of the rural settlements continued to expand. Settlements were distributed randomly, but an agglomeration trend began to appear. The plain terrain had little restriction on settlement site selection. Cofferdams and embankments were the limiting factors for settlement expansion, which led to the compact development of the settlements. Economic development, population growth, and family miniaturization were positive factors for the expansion of the rural settlements. In the typical villages, cluster settlements and cluster settlements with a banded tendency had higher spatial utilization efficiency. Several high-density building centers were formed in the settlements, and the trend of residential buildings was mainly northeast–southwest. The plain terrain had little effect on the orientation of buildings, single-building areas, or the public spaces of the settlements. Traditional culture and traffic routes affected the orientation of the main buildings of folk houses. This study has theoretical and reference value for the structure optimization and sustainable development of rural settlements in the lower Yellow River plain.

A GIS-based multi-criteria decision analysis approach using AHP for rural settlement site selection and eco-village design in Erzincan, Turkey

In recent years, natural resource depletion, rapid population growth, and increasing urbanization have all reached new heights. All of these ecological problems that exceed the planet's absorbing capacity, have begun to imperil both human life and nature itself. Rural settlement plans aim to optimize the use of natural resources. Agricultural lands are used for non-agricultural purposes as a result of proper placement planning of rural settlements. The suitability of land for a specific purpose is determined via suitability analysis. Therefore, it is extremely important to use technological innovations in the selection of rural settlement areas in addition to considering the technical, economic, and social factors in determining the most suitable locations. With the advancement of computer technology, Geographical Information System (GIS) has become an important tool for more effective use of rural areas. In this study, the most suitable rural settlement area was determined by using GIS in Erzincan Province. Technical, social, cultural, and economic criteria were developed for the selection of the location. Alternative locations were analyzed using the GIS, Multi-Criteria Decision Analysis and the Analytical Hierarchy Process method based on the criteria and site data. The most suitable areas for rural settlements were chosen as the Merkez, Tercan, Kemaliye, and Kemah districts in Erzincan Province. Çağlayan town in the Merkez district has been determined as the most suitable region for an eco-village and a cost calculation and 3D eco-village design were carried out in Çağlayan.

Analysis on the Layout of Traditional Residential Courtyards and Building Structures in Guanzhong Area, Shaanxi——Taking Xiaojiapo Village in Lantian County as an example

Traditional houses in Guanzhong area are typical regional sustainable green buildings, which contain ecological wisdom and cultural connotations that are in harmony with the environment. This article takes Xiaojiapo Village in Lantian County as the research object. Based on the integration of traditional residential culture inheritance and green development, this paper conducts a more systematic study on settlement site selection, courtyard layout, and building structure. “Road” Shaanxi section of traditional residential building art and folk culture subject research has added results, and also provides an early stage for the protection and inheritance of traditional residential buildings in the Guanzhong area.

Integration of an InSAR and ANN for Sinkhole Susceptibility Mapping: A Case Study from Kirikkale-Delice (Turkey)

Suitable route determination for linear engineering structures is a fundamental problem in engineering geology. Rapid evaluation of alternative routes is essential, and novel approaches are indispensable. This study aims to integrate various InSAR (Interferometric Synthetic Aperture Radar) techniques for sinkhole susceptibility mapping in the Kirikkale-Delice Region of Turkey, in which sinkhole formations have been observed in evaporitic units and a high-speed train railway route has been planned. Nine months (2019–2020) of ground deformations were determined using data from the European Space Agency’s (ESA) Sentinel-1A/1B satellites. A sinkhole inventory was prepared manually using satellite optical imagery and employed in an ANN (Artificial Neural Network) model with topographic conditioning factors derived from InSAR digital elevation models (DEMs) and morphological lineaments. The results indicate that high deformation areas on the vertical displacement map and sinkhole-prone areas on the sinkhole susceptibility map (SSM) almost coincide. InSAR techniques are useful for long-term deformation monitoring and can be successfully associated in sinkhole susceptibility mapping using an ANN. Continuous monitoring is recommended for existing sinkholes and highly susceptible areas, and SSMs should be updated with new results. Up-to-date SSMs are crucial for the route selection, planning, and construction of important transportation elements, as well as settlement site selection, in such regions.

Study on spatial layout optimization of Linpan settlements based on point pattern analysis

According to the problems of lack of planning and disordered layout of rural settlements in China, it is urgent to further improve the methods of optimizing the settlement pattern of towns and villages and the intensive use of land. The main purpose of this paper is to optimize the layout of rural settlements with a single land-use type and a large number of rural settlements to be relocated. This paper takes the Linpan settlements of Deyuan Town, Chengdu City, Sichuan Province as the research object and establishes the suitability evaluation system of Linpan settlements by the Entropy method. The Linpan settlements of research area are divided into the central and the non-central Linpan settlements and determine the search threshold according to the point pattern analysis method and multi-distance spatial cluster analysis. Through the study of regional preliminary central Linpan settlement selection and search threshold determination, central Linpan settlement site selection, the determination of non-central Linpan settlement’s migration direction, the results show that the radiation coverage rate of the central Linpan increased by 17.3%, the number of repeated radiation Linpans decreased by 63.2%, the overlapping area decreased by 49.9%, and finally 179 Linpans were optimized and merged into 36 central Linpans.

Where mobile groups settle: Spatial patterns and correlates of Maasai pastoralist sedentarization in Northern Tanzania

In the last century, mobile pastoralists around the world have transitioned to more sedentary lifestyles. Traditionally mobile people can be both pushed to settle by environmental or political forces, and pulled by new economic activities. While researchers have examined the causes and consequences of growing sedentarization, few contemporary studies have focused on the spatial patterns of settlement. This study examines settlement site selection using GIS and remote sensing techniques to quantify patterns and correlates of settlement location in four Maasai communities in northern Tanzania. We identify landscape scale factors that shape settlement locations and test the competing hypotheses that settlement is associated with: (1) resource access; (2) environmental constraints; and (3) infrastructural amenities. Spatial models offer support for each hypothesis, with slight variations. However, a combined model offers the greatest predictive power suggesting significant heterogeneity in site selection and/or a transition in selection criteria over time. These findings characterize a poorly understood aspect of the settlement of mobile groups, and point to new questions regarding the spatial drivers and consequences of sedentarization.

Sniffing out the competition? Juvenile coral reef damselfishes use chemical cues to distinguish the presence of conspecific and heterospecific aggregations

Aquatic animals commonly rely on chemical cues to provide information regarding their surroundings. They can respond either by being attracted to (potential mates, preferred habitats) or avoiding (predators, competitors) the source of the stimuli. Coral reef fishes use chemical cues to detect habitats, avoid predators and recognise conspecifics. However, the extent to which chemical cues are used to detect and respond to potential competitors, has received little attention. Here we test olfactory preferences for conspecifics and heterospecifics in newly settled juvenile coral reef fishes. Juveniles of 4 common coral-associated damselfish species: Dascyllus melanurus, Dascyllus reticulatus, Chrysiptera arnazae and Pomacentrus moluccensis, were subjected to olfactory choice tests. Three of the 4 species (excluding P. moluccensis) demonstrated preferences for waterborne conspecifics odours. All species exhibited an avoidance towards heterospecific odours; this aversion was consistently greatest towards P. moluccensis. A neutral response toward heterospecifics was only evident in two instances (1) between the two congeneric Dascyllus species, with D. melanurus toward D. reticulatus, and (2) with C. arnazae toward D. melanurus. While it is already known that the presence of conspecifics plays a vital role in settlement site selection, we show here that the presence of heterospecifics may also be key in determining the spatial distributions of juveniles across areas of coral reef.

Improving efficiency for post-disaster transitional housing in Indonesia

Purpose– Natural hazards occur frequently in Indonesia. When post-disaster recovery is prolonged and complicated, it is necessary to provide accommodations for homeless refugees in disaster areas. Since a transitional housing solution includes planning, design and execution phases, the design phase implements the decisions made in the planning phase and also affects the results of the execution phase. Therefore, the purpose of this paper is to assist communities to effectively deal with various processes during the design phase involving transitional housing solutions.Design/methodology/approach– Based on eight factors associated with “building back better” and ten principles of transitional housing, the paper identified three problems in the design phase: inappropriate selection of settlement sites, improper representation of housing facilities and ineffective scheduling of construction projects. To resolve these problems, this study integrated a geographic information system (GIS), three-dimensional (3D) building models and construction project management tools to assess settlement sites, confirm housing facilities and configure construction projects, respectively.Findings– After this study tested conventional methods (e.g. paper-based maps, drawings, reports) and the proposed approach, the results revealed that communities can appropriately determine settlement sites based on the GIS. The 3D building models enabled the communities to understand the external and internal layouts of housing facilities. Through construction project management, the communities could consider construction activities immediately when preparing the execution phase for transitional housing solutions.Originality/value– This study offers a useful reference for similar applications in post-disaster reconstruction and management.

Movements and settlement site selection of pygmy rabbits after experimental translocation

We investigated the movements and selection of settlement sites of translocated pygmy rabbits (Brachylagus idahoensis) in southeastern Oregon from June to December 2008. We captured, radio tagged, and translocated 59 pygmy rabbits across big sagebrush (Artemisia tridentata ssp.) habitat with 3 categories of landscape fragmentation. We used radio telemetry to track the movements and document the fates of translocated individuals. We used Geographic Information Systems (GIS) and spatial analysis software (FRAGSTATS) to analyze the post-release movements and selection of settlement sites by pygmy rabbits. We found that pygmy rabbits settled closer to their release sites as the amount big sagebrush cover on the surroundinglandscapeincreased.Inaddition,translocatedpygmyrabbits settled onsitesthat,onaverage,had greater cover, greater landscape connectivity, and fewer but larger patches of big sagebrush than were present at their capture sites. Current or past presence of conspecifics also appeared to be a factor in selection of settlement sites by pygmy rabbits. Successful translocation of wild pygmy rabbits for augmenting depleted populations will require selection of release locations with continuous big sagebrush cover and a history of pygmy rabbit presence. Managers should also expect to lose a portion of translocated pygmy rabbits to homing attempts, post-release dispersal, and predation, so large numbers of individuals should be released to establish resident populations. 2013 The Wildlife Society.

Predation risk assessment by larval reef fishes during settlement-site selection

Predation rates of marine species are often highest during the transition from the pelagic to the benthic life stage. Consequently, the ability to assess predation risk when selecting a settlement site can be critical to survival. In this study, pairwise choice trials were used to determine whether larvae of three species of anemonefish (Amphiprion melanopus, A. percula and Premnas biaculeatus) are able to (1) assess the predation risk of potential anemone settlement sites through olfactory cues alone and (2) alter their settlement choices depending on the options available (host or non-host anemone). When predation risk was assessed with host and non-host anemone species independently, all species of anemonefish significantly chose the odor associated with the low-risk settlement option over the high-risk site. Most importantly, all species of anemonefish selected water with olfactory cues from their host anemone regardless of predation risk when paired against non-host anemone odor. These results demonstrate that larval reef fishes can use olfactory cues for complex risk assessment during settlement-site selection; however, locating the correct habitat is the most important factor when selecting a settlement site.

Terrestrial chemical cues help coral reef fish larvae locate settlement habitat surrounding islands

Understanding the degree of connectivity between coastal and island landscapes and nearby coral reefs is vital to the integrated management of terrestrial and marine environments in the tropics. Coral reef fish are capable of navigating appropriate settlement habitats following their pelagic larval phase, but the mechanisms by which they do this are unclear. The importance of olfactory cues in settlement site selection has been demonstrated, and there is increasing evidence that chemical cues from terrestrial sources may be important for some species. Here, we test the olfactory preferences of eight island-associated coral reef fish recruits and one generalist species to discern the capacity for terrestrial cue recognition that may aid in settlement site selection. A series of pairwise choice experiments were used to evaluate the potential role that terrestrial, water-borne olfactory cues play in island–reef recognition. Olfactory stimuli tested included near-shore water, terrestrial rainforest leaf litter, and olfactory cues collected from different reef types (reefs surrounding vegetated islands, and reefs with no islands present). All eight island-associated species demonstrated high levels of olfactory discrimination and responded positively toward olfactory cues indicating the presence of a vegetated island. We hypothesize that although these fish use a suite of cues for settlement site recognition, one mechanism in locating their island/reef habitat is through the olfactory cues produced by vegetated islands. This research highlights the role terrestrial olfactory cues play in large-scale settlement site selection and suggests a high degree of ecosystem connectivity.

Ontogenetic changes in responses to settlement cues by Anemonefish

Population connectivity for most marine species is dictated by dispersal during the pelagic larval stage. Although reef fish larvae are known to display behavioral adaptations that influence settlement site selection, little is known about the development of behavioral preferences throughout the larval phase. Whether larvae are attracted to the same sensory cues throughout their larval phase, or exhibit distinct ontogenetic shifts in sensory preference is unknown. Here, we demonstrate an ontogenetic shift in olfactory cue preferences for two species of anemonefish, a process that could aid in understanding both patterns of dispersal and settlement. Aquarium-bred naive Amphiprion percula and A. melanopus larvae were tested for olfactory preference of relevant reef-associated chemical cues throughout the 11-day pelagic larval stage. Age posthatching had a significant effect on the preference for olfactory cues from host anemones and live corals for both species. Preferences of olfactory cues from tropical plants of A. percula, increased by approximately ninefold between hatching and settlement, with A. percula larvae showing a fivefold increase in preference for the olfactory cue produced by the grass species. Larval age had no effect on the olfactory preference for untreated seawater over the swamp-based tree Melaleuca nervosa, which was always avoided compared with blank seawater. These results indicate that reef fish larvae are capable of utilizing olfactory cues early in the larval stage and may be predisposed to disperse away from reefs, with innate olfactory preferences drawing newly hatched larvae into the pelagic environment. Toward the end of the larval phase, larvae become attracted to the olfactory cues of appropriate habitats, which may assist them in identification of and navigation toward suitable settlement sites.

Behavioral plasticity in larval reef fish: orientation is influenced by recent acoustic experiences

Animals use many different cues to orient in their environment, solve directional movement challenges, and select suitable habitat. Recent work has highlighted the importance of the ambient soundscape in providing orientation cues for larvae of coral reef fishes at the key life-history phase when they recruit from open ocean to coral reef environments. In this study, we combined acoustic conditioning with binary choice chambers and used 442 settlement-stage larvae from 4 Pomacentridae (damselfish) species (Pomacentrus amboinensis, P. brachialis, P. moluccensis, and P. nagasakiensis) to test whether responses to acoustic cues are fixed or whether behavior is influenced by recent acoustic experience. Over 8 trials, groups of wild-caught larvae that experienced noise (natural reef noise or artificial tone noise) during a 12-h conditioning period showed a positive directional response to reef noise in the chambers. Groups conditioned with reef noise responded adversely to the tone noise, whereas groups conditioned to the artificial tones were subsequently attracted by them. This plasticity in behavior suggests that settlement-stage larval reef fish (;20 days old) are influenced by, and can retain information from, recent acoustic experiences. Behavioral plasticity may enable greater control by larvae over their selection of settlement sites but could also mean that anthropogenic sounds have more than masking effects on the orientation behavior of fishes. Key words: acoustic cues, choice chambers, coral reef fishes, orientation, Pomacentridae. [Behav Ecol]

The adhesive strategies of cyprids and development of barnacle-resistant marine coatings

Over the last decade, approaches to the development of surfaces that perturb settlement and/or adhesion by barnacles have diversified substantially. Although, previously, coatings research focussed almost exclusively on biocidal technologies and low modulus, low surface-free-energy ‘fouling-release’ materials, novel strategies to control surface colonisation are now receiving significant attention. It is timely, therefore, to review the current ‘state of knowledge’ regarding fouling-resistant surface characteristics and their mechanisms of action against settling larvae of barnacles. The role of the barnacle in marine fouling is discussed here in the context of its life cycle and the behavioural ecology of its cypris larva. The temporary and permanent adhesion mechanisms of cyprids are covered in detail and an overview of adult barnacle adhesion is presented. Recent legislation has directed academic research firmly towards environmentally inert marine coatings, so the actions of traditional biocides on barnacles are not described here. Instead, the discussion is restricted to those surface modifications that interfere with settlement-site selection and adhesion of barnacle cypris larvae; specifically, textural engineering of surfaces, development of inert ‘non-fouling’ surfaces and the use of enzymes in antifouling.

Marine natural products influencing larval settlement and metamorphosis of marine sessile organisms

Most marine sessile organisms have a planktonic larval phase in their life cycles, and then larvae settle and metamorphose into their adult forms. The selection of settlement sites is a critical event for these organisms because settlement on unsuitable places affects their survivorship severely. Ascidians live gregariously, and conspecific chemical cues are thought to play an important role in gregarious settlement of larvae. The extracts of conspecific adults or larvae have been claimed to contain "natural metamorphosis inducers." Little is known, however, about their chemical properties. To discover natural signal substances for larval metamorphosis in ascidians, we surveyed the metamorphosis-inducing activity of the medium conditioned by ascidian larvae, and succeeded in isolating a metamorphosis-inducing substance from the conditioned medium of Halocycthia roretzi larvae and found that it was identical to lumichrome. We have also isolated more than 40 active metabolites, which may mimic lumichrome, from marine sponges. On the contrary, marine sessile organisms cause serious problems by settling on fishing nets, hulls of ships, and cooling systems of power plants. Organotin compounds have been widely used for the control of these organisms, but they are known to be toxic to marine biota. Therefore, nontoxic antifouling substances are urgently needed. Marine sessile organisms possess chemical defense systems using their secondary metabolites, which might be potential by nontoxic antifouling agents. We have attempted to obtain antibarnacle substances from marine sponges and isolated 26 antifoulants.

Influence of substratum heterogeneity scales and complexity on a temperate epibenthic marine community

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 189:159-170 (1999) - doi:10.3354/meps189159 Influence of substratum heterogeneity scales and complexity on a temperate epibenthic marine community Louise Lapointe, Edwin Bourget* GIROQ, Département de biologie, Université Laval, Ste-Foy, Québec G1K 7P4, Canada *E-mail: edwin.bourget@fsg.ulaval.ca ABSTRACT: The influence of 4 scales of substratum heterogeneity on the establishment of a temperate sessile marine epibenthic community (Beaufort, North Carolina, USA) was examined over a period of 1 yr. Artificial panels with crevices representing 4 scales of heterogeneity of 0, 1, 10 and 100 mm and with combinations of these crevices representing 4 levels of complexity (0+1+10, 0+1+100, 0+10+100 and 0+1+10+100 mm) were deployed in January 1991 and sampled in March, June, September 1991, and January 1992. Significant temporal changes in abundance (% cover) and species dominance were observed during each sample period. Initially (within 5 mo after immersion), significantly lower abundances occurred on panels with the 1 mm scale compared with panels without this scale. Changes in diversity appeared to be related mainly to the 100 mm scale of heterogeneity regardless of the complexity level: diversity values found on panels which included the 100 mm crevices were initially low, but exceeded that of all other panels by January (1 yr after immersion). In summary, panel complexity was not the major factor influencing community structure, but the scale of heterogeneity (1 mm for abundances and 100 mm for diversity) had important and significant effects. These results indicate the specific importance of the 1 mm scale not only during the larval settlement phase but also during the development of the community. We compared these results with laboratory experiments using inert particles and similar panels, whose results suggest that larval behaviour is involved in the selection of settlement sites. KEY WORDS: Substratum heterogeneity · Substratum complexity · Epibenthic marine community · Larval behaviour · Intertidal Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 189. Publication date: November 26, 1999 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1999 Inter-Research.

Effects of chemical cues on settlement behavior of blue crab Callinectes sapidus postlarvae

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 154:143-153 (1997) - doi:10.3354/meps154143 Effects of chemical cues on settlement behavior of blue crab Callinectes sapidus postlarvae Welch JM, Rittschof D, Bullock TM, Forward RB Jr Settlement of blue crab Callinectes sapidus Rathbun postlarvae (megalopae) was examined in the field in the presence and absence of chemical cues from settlement habitats and potential megalopal predators. Megalopae in premolt preferentially settled on collectors containing seagrasses Zostera marina and Halodule wrightii, but not on collectors with salt marsh cordgrass Spartina alterniflora. Settlement of megalopae was reduced by up to 40% in the presence of predators from several different habitats, including crabs Uca pugilator, U. pugnax and Panopeus herbstii, and grass shrimp Palaemonetes pugio. Laboratory predation assays showed that each of these potential predators ate C. sapidus megalopae if they encountered them. Megalopae avoided odors of U. pugilator in chemotaxis assays, and showed no reaction to odors from Z. marina and S. alterniflora. Settlement of megalopae was unaffected by the presence of adult C. sapidus or brown shrimp Penaeus aztecus, neither of which consumed megalopae in laboratory predation assays. Megalopae showed no reaction to fouled shells of oyster Crassostrea virginica, but avoided live C. virginica. Thus, settling blue crab megalopae can distinguish among settlement sites using chemical cues, and their discrimination ability increases in the premolt stage. Chemical cues · Settlement site selection · Callinectes sapidus · Megalopae · Post-<\n>larvae · Eelgrass · Predators · Chemotaxis · Blue crab Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 154. Publication date: July 31, 1997 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1997 Inter-Research.

Factors affecting spatial preferences in settlement site selection in migratory pastoralism

Factors affecting spatial preferences in settlement site selection in migratory pastoralism

Effects of selective settlement and of aggression by residents on distribution of young recruits of two tropical damselfishes

The reef fishes that settled on an array of experimental corals at Lizard Island, Queensland, Australia, were counted during a pulse of recruitment in December 1986. NeitherPomacentrus sp. norP. amboinensis showed any evidence that harassment by residentDascyllus aruanus caused a decrease in persistence during the first day after settlement. LarvalPomacentrus sp. settled selectively on corals without residentD. aruanus. The results forP. amboinensis were ambiguous. Settlers of both species positioned themselves closer to the sand on corals with residentD. aruanus than on unoccupied corals. This could reduce access to planktonic food and increase the risk of predation. Adult aggression may be less important and active selection of settlement sites by larvae may be more important to the distribution of recruits than is suggested by the literature. The presence or absence of particular species should be included among the cues that larval reef fishes use to choose settlement sites.