Creation Of Patches Research Articles

Anthropogenic pressure in Czech protected areas over the last 60 years: A concerning increase

This article focuses on the evolution of anthropogenic pressure across Czech large-scale protected areas (protected landscape areas and national parks, n = 30) over the last 60 years. In four periods (1960s; 1990; 2004; between 2016 and 2020) we analysed the development of artificial structures (built-up areas, recreational areas, roads, dirt roads, and streets) and their impact on landscape fragmentation. These spatial data were derived from topographic maps and aerial imageries and then statistically compared. Principally, built-up and recreational areas have increased; however, intensity varied across protected areas (PAs). Built-up areas have grown more in PAs close to large towns, especially after 1990 as protection did not prevent suburbanization in the PAs. Furthermore, PAs with more built-up areas also have more buildable areas; therefore, further ongoing development is expected. Recreational areas are present the most in some mountainous areas, such as ski resorts, and near large towns and spa towns (e.g. golf courses). The density of roads was more or less stable during the study period. Dirt road density differed within PAs according to the prevalent type of landscape: growth or stagnation in forested areas due to recreation and logging purposes and a decline in agricultural land, mainly as a consequence of collectivization in 1950 s followed by landscape unification and the creation of large patches of agricultural land. To sum up, anthropogenic pressure increased with landscape fragmentation, but these impacts are different across Czechia; in peripheral, attractive or peri-urban areas, which is important from landscape management point of view.

Trophic position determines the persistence of neotropical understory birds after forest disturbance.

Habitat loss and degradation are key drivers of the current biodiversity crisis. Most research focuses on the question of which traits allow species to persist in degraded habitats. We asked whether a species' trophic position or niche width influences the resilience of species in degraded habitats and to what extent habitat degradation affects trophic interactions between species. We used nitrogen isotope ratios (15N:14N, expressed as δ15N value) to quantify and compare trophic positions and niche widths of understory birds inhabiting old-growth and young secondary forests in the Pacific lowlands of Costa Rica. We found that a species' trophic position rather than its trophic niche width determined its persistence in secondary forests. Species feeding at lower trophic levels in old-growth forests were less likely to persist in secondary forests than those occupying a higher trophic position in old-growth forests. This pattern is likely induced by the occurrence of relatively large-bodied habitat specialists with a flexible and high-trophic level diet in secondary forests. These habitat specialists likely caused generalist bird species to lower their trophic position relative to conspecifics in old-growth forests. Regarding trophic niche widths, species in secondary forests tend to have larger niche widths than old-growth forest species. However, as old-growth forest specialists and generalists did not differ in their niche widths, no systematic effect of trophic niche width on species persistence after forest disturbance was found. This is the first study that shows a systematic effect of trophic position on the persistence of a wide range of bird species in a disturbed forest ecosystem. It therefore provides important insights into species' responses to habitat degradation and the conservation value of secondary forests. To improve habitat quality for old-growth forest birds and facilitate avian seed dispersal, the creation of large contiguous forest patches should be prioritised when implementing reforestation measures.

Optical creation and annihilation of skyrmion patches in a chiral magnet

Optical creation and annihilation of skyrmion patches in a chiral magnet

A Comprehensive Review on the Development of Transdermal Patches for Sustained Release of Medication in Migraine Therapy

This extensive review study focuses on the developments and difficulties in the creation of transdermal patches for the treatment of migraines. Migraine is a common neurological condition marked by crippling headaches and frequently need early and effective treatment. A potential method for sustaining medication administration, transdermal patches provide regular dose and boost patient compliance. The composition of transdermal patches, the method of drug release, benefits, drawbacks, and potential applications in the treatment of migraines are all covered in this article.

The Spatiotemporal Changing Dynamics of Miombo Deforestation and Illegal Human Activities for Forest Fire in Kundelungu National Park, Democratic Republic of the Congo

In the Kundelungu National Park (KNP), southeast of the Democratic Republic of Congo, illicit human activities including recurrent bushfires contribute to constant regression of forest cover. This study quantifies the landscape dynamics and analyses the spatio-temporal distribution of bushfire occurrence within KNP. Based on classified Landsat images from 2001, 2008, 2015 and 2022, the evolutionary trend of land cover was mapped and quantified through landscape metrics. The spatial transformation processes underlying the observed landscape dynamics were identified based on a decision tree. Finally, the spatio-temporal fire risk assessment was carried out after defining the burnt areas for each year between 2001 and 2022. The obtained results, expressed by the process of dissection and attrition of patches, show that the forest cover has regressed from 2339 km2 to 1596 km2 within the PNK, with an annual deforestation rate varying from 0.8% to 3.4% between 2001 and 2022. Over the same period, the average distance between forest patches has increased significantly, indicating fragmentation and spatial isolation. On the other hand, savannahs as well as field and fallow mosaics have expanded within KNP through the creation of new patches. In addition, several active fires affected more savannahs between 2001 (70 km2 in Integral Zone, 239 km2 in Annex Zone and 309 km2 in KNP) and 2022 (76 km2 in Integral Zone, 744 km2 in Annex Zone and 819 km2 in KNP), limiting their capacity to evolve into forests. Overall, anthropogenic pressure is higher in the Annex Zone of the KNP. Illegal agricultural development and vegetation fires have thus doubled the level of landscape disturbance in 21 years. Our observations justify the need to strengthen protection measures for KNP by limiting repeated human intrusions.

A multi-staged drift sand geo-archive from the Netherlands: New evidence for the impact of prehistoric land use on the geomorphic stability, soils, and vegetation of aeolian sand landscapes

The drift sand area near Hilversum, the Netherlands, holds a geo-archive with multiple drift sand phases and intercalated palaeosols. We studied this area to test earlier theories on the development of podzols in such aeolian sands, the occurrence of sand drifting, and the contemporary vegetation development, and to gain insight into the early human impacts on these fragile ecosystems. Based on OSL and radiocarbon datings, palaeoecological studies, and soil chemical analyses, the age and origin of the drift sand phases and palaeosols were established. Sand drifting started around 6000 BCE (Late Mesolithic), the drift sand covering a distinct podzol in the Younger Cover Sand II. A second Late Mesolithic drift sand phase dated from ca. 4900–4500 BCE. Three later drift sand phases were distinguished of which the last is the classic Late Medieval (and younger) phase, while the first two date from the Neolithic. All intercalated palaeosols exhibited more or less prominent podzolisation. The palaeocological data showed that, prior to the Neolithic, in the forest open patches had developed with non-arboreal vegetation, dominated by Poaceae and Ericaceae. This changed during the Neolithic, most probably linked to the introduction of crop farming, the vegetation gradually acquiring the characteristics of the classic heathland with patches of trees/shrubs. The early sand drifting, podzolisation and opening of the forest are attributed to Mesolithic land use, with intentional burning as major factor. We conclude that the local destruction of the deciduous forests by fire and associated creation of open patches with bare sand were essential for the early sand drifting and podzolisation to occur. The results shed new light on the origin of drift sands, heathlands, and podzols in the Netherlands, and on the environmental impacts of Mesolithic people, and testify to the fundamental instability of these dry inland dune ecosystems.

You Reap What You Sow: A Botanical and Economic Assessment of Wildflower Seed Mixes Available in Ireland

Planting wildflower seed mixes has become popular with individuals and community groups aiming to promote wildlife and enhance local biodiversity. Recently, however, these seed mixes have been criticized with respect to the origin of the seeds and the species they contain. There is a growing awareness that the unintended planting of exotic species may disrupt native ecological networks, introduce aggressive weeds, or facilitate the establishment of invasive species in new localities. In this study, we purchased two packets of twelve brands of wildflower seeds available in Ireland from stores or online suppliers. In total, the 24 packets contained 69,409 seeds weighing 304 g, and represented 92 plant species in 23 families. Only 25% of the seed packets purchased in Ireland originated from Ireland, and only 43% of the plant species we identified are considered native to Ireland. To reinforce this point, the most frequent species, Phacelia tanacetifolia, which occurred in nine of the twelve brands, is not a native Irish plant species. Multivariate analysis identified no obvious grouping of seed mixes based on their intended target group (e.g., bees, butterflies, wildlife), which might be expected had manufacturers followed scientific guidance describing which plants are preferred by which pollinator group. The creation of patches of diverse floral habitats in gardens and urban settings can significantly benefit wildlife and human wellbeing. Our results, however, reinforce the need for caution before using wildflower mixes in attempts to restore or recreate natural or semi-natural plant communities.

Thinking Outside the Continent and Outside the Box: Cross-Continental Comparative Studies Can Enrich Studies of Pre-Columbian Raised-Field Agriculture

Despite an attempt at intercontinental synthesis by Denevan and Turner (1974) almost 50 years ago, studies of agricultural raised fields (RF) in the Neotropics and in Africa and New Guinea are separate research traditions, with almost no communication between them. Neotropical studies refer to “raised-field agriculture” and almost exclusively concern archaeological systems in wetlands. Studies in Africa and New Guinea refer to “mound” or “ridge” cultivation and concern mostly present-day systems (in Africa) or both present-day and archaeological systems (in New Guinea) in both uplands and wetlands. Ethnographic studies of present-day systems provide insights into questions about past systems that are inaccessible using archaeological methods alone. Our review suggests that the Neotropical focus on RF agriculture as an exclusively wetland adaptation is misleading. We argue that the most widespread purpose of building RF, in both wetland and upland environments, is to concentrate topsoil and organic matter, enabling creation of fertile patches in infertile and low-biomass grassland environments. Avoiding flooding is an important function of RF built in wetlands and wetland margins. We further show that Old World RF are often not perennial, but are short-lived structures that rotate over the landscape, being torn down and rebuilt nearby in successive cycles. Short fallow periods are allowed (or even favored) by methods of managing fertility. Finally, we argue that the restriction—on all continents—of archaeological raised fields to wetland and wetland-margin environments is, in part, a result of their better preservation from erosion in wetland than in upland environments.

Eco-cultural Restoration of Riparian Wetlands in California: Case Study of White Root (Carex barbarae Dewey; Cyperaceae)

This study defines the cultural and ecological significance of white root (Carex barbarae Dewey; Cyperaceae), and presents a template for eco-cultural restoration, drawing from both Traditional Ecological Knowledge and Scientific Ecological Knowledge. Carex barbarae is an herbaceous perennial understory plant in valley oak riparian woodlands, endemic to California and southern Oregon. Referred to as white root, C. barbarae is an indicator species of both cultural and ecological health. Two-thirds of the California Indian tribes within the range of white root historically tended and managed these sedges for basketweaving. Traditional management by Indian groups resulted in the creation and maintenance of homogeneous patches throughout low-elevation riparian forests of California, maintaining a lawn-like understory and a park-like physiognomy. Gathering and tending practices significantly influenced the distribution, quality and abundance of white root beds on species, community, and landscape scales. Understanding how indigenous people shaped their environment using Traditional Resource Management practices and related ecological effects is integral to successful contemporary restoration of riparian habitats. Understanding the reciprocal relationships between California Indians and their sovereign landscape is important to contemporary indigenous cultures and their identity, resilience, and vitality.

Automatic surface mesh generation for discrete models – A complete and automatic pipeline based on reparametrization

Triangulations are an ubiquitous input for the finite element community. However, most raw triangulations obtained by imaging techniques are unsuitable as-is for finite element analysis. In this paper, we give a robust pipeline for handling those triangulations, based on the computation of a one-to-one parametrization for automatically selected patches of input triangles, which makes each patch amenable to remeshing by standard finite element meshing algorithms. Using only geometrical arguments, we prove that a discrete parametrization of a patch is one-to-one if (and only if) its image in the parameter space is such that all parametric triangles have a positive area. We then derive a non-standard linear discretization scheme based on mean value coordinates to compute such one-to-one parametrizations, and show that the scheme does not discretize a Laplacian on a structured mesh. The proposed pipeline is implemented in the open source mesh generator Gmsh, where the creation of suitable patches is based on triangulation topology and parametrization quality, combined with feature edge detection. Several examples illustrate the robustness of the resulting implementation.

Species traits, patch turnover and successional dynamics: when does intermediate disturbance favour metapopulation occupancy?

BackgroundIn fragmented landscapes, natural and anthropogenic disturbances coupled with successional processes result in the destruction and creation of habitat patches. Disturbances are expected to reduce metapopulation occupancy for species associated with stable habitats, but they may benefit species adapted to transitory habitats by maintaining a dynamic mosaic of successional stages. However, while early-successional species may be favoured by very frequent disturbances resetting successional dynamics, metapopulation occupancy may be highest at intermediate disturbance levels for species with mid-successional habitat preferences, though this may be conditional on species traits and patch network characteristics. Here we test this ‘intermediate disturbance hypothesis’ applied to metapopulations (MIDH), using stochastic patch occupancy simulation modelling to assess when does intermediate disturbance favour metapopulation occupancy. We focused on 54 virtual species varying in their habitat preferences, dispersal abilities and local extinction and colonization rates. Long-term metapopulation dynamics was estimated in landscapes with different habitat amounts and patch turnover rates (i.e. disturbance frequency).ResultsEquilibrium metapopulation occupancy by late-successional species strongly declined with increasing disturbance frequency, while occupancy by early-successional species increased with disturbance frequency at low disturbance levels and tended to level-off thereafter. Occupancy by mid-successional species tended to increase along with disturbance frequency at low disturbance levels and declining thereafter. Irrespective of habitat preferences, occupancy increased with the amount of habitat, and with species dispersal ability and colonisation efficiency.ConclusionsOur study suggests that MIDH is verified only for species associated with mid-successional habitats. These species may be particularly sensitive to land use changes causing either increases or decreases in disturbance frequency. This may be the case, for instance, of species associated with traditional agricultural and pastoral mosaic landscapes, where many species disappear either through intensification or abandonment processes that change disturbance frequency.

Relative importance of landscape and species characteristics on extinction debt, immigration credit and relaxation time after habitat turnover

AbstractHabitat turnover concomitantly causes destruction and creation of habitat patches. Following such a perturbation, metapopulations harbor either an extinction debt or an immigration credit, that is the future decrease or increase in population numbers due to this disturbance. Extinction debt and immigration credit are rarely considered simultaneously and disentangled from the relaxation time (time to new equilibrium). In this contribution, we test the relative importance of two potential drivers of time‐delayed metapopulation dynamics: the spatial configuration of the habitat turnover and species dispersal ability. We provide a simulation‐based investigation projecting metapopulation dynamics following habitat turnover in virtual landscapes. We consider two virtual species (a short‐distance and a long‐distance disperser) and five scenarios of habitat turnover depending on net habitat loss or gain and habitat aggregation. Our analyses reveal that (a) the main determinant of the magnitude of the extinction debt or immigration credit is the net change in total habitat area, followed by species dispersal distance and finally by the post‐turnover habitat aggregation; (b) relaxation time weakly depends on the magnitude of the immigration credit or of the extinction debt; (c) the main determinant of relaxation time is dispersal distance followed by the net change in total habitat area and finally by the post‐turnover habitat aggregation. These results shed light on the relative importance of dispersal ability and habitat turnover spatial structure on the components of time‐delayed metapopulation dynamics.

Amplification of Anthropogenic Pressure Heavily Hampers Natural Ecosystems Regeneration within the Savanization Halo Around Lubumbashi City (Democratic Republic of Congo)

Located in the south-east of the Democratic Republic of Congo (DR Congo), Lubumbashi city is surrounded by a belt of savanna, referred to as “savanization halo†, where rare miombo woodland patches could be spotted. This study evaluated the impact of anthropogenic activities on changes in the spatio-temporal pattern within that savanization halo between 2002 and 2017. A mapping approach coupled with landscape ecology analysis tools enabled highlighting both the diagnosis of land cover changes and the processes underlying the spatio-temporal dynamics. Results globally attested that the savanization halo was in constant mutation from 2002 to 2017. Importantly, it was apparent that the dissection, fragmentation and attrition of miombo was amplified by the creation and aggregation of savanna and built-up-bare land complex. Wetland attrition was found to be an additional manifestation of natural ecosystem degradation, with the resulting bare soils suggested as being flooded through the creation of waterbody patches. Agricultural and infrastructural development, supported by rapid population growth, no longer allows natural formations (forest and wetland) to recover from disturbances. It is important to reverse the current trend towards complete anthropization within the savanization halo through selective protection of natural ecosystems according to their values.

Gene Regulation of BMP Ligands in Drosophila.

Drosophila is a valuable system to study bone morphogenetic proteins (BMPs) due to the high functional conservation of the pathway and the molecular genetic tools available. Drosophila has three BMP ligands, decapentaplegic (BMP2/4), screw, and glass bottom boat (BMP5/6/7/8). Of these genes, the transcriptional regulation of decapentaplegic has been studied, and some of the enhancers directing its spatially specific gene expression have been described. These analyses have used many of the standard tools of molecular biology, but a valuable method of analysis often used in Drosophila is the creation of patches of mutant tissue at any stage and in any location by induced somatic recombination. The ability to create transgenic flies and manipulate the Drosophila genome with recombinases is well established. This method can be used to evaluate the requirements for specific transcription factors to act on enhancer elements in vivo, in stage- and tissue-specific manners. The yeast FLP/FRT recombination system facilitates experiments to interrogate loss- or gain-of-function for transcription factor activity on known enhancers. This chapter will outline the necessary steps to create the tools needed and conduct somatic cell recombination experiments to interrogate the function of transcription factors on BMP enhancers.

Population dynamics and future persistence of the clouded Apollo butterfly in southern Scandinavia: The importance of low intensity grazing and creation of habitat patches

We investigated the population dynamics and future persistence of the last remaining Clouded Apollo butterfly metapopulation in southern Scandinavia. Based on three decades of surveys (1984–2015), we modelled colonization-extinction dynamics and local population sizes using habitat patch characteristics and connectivity, while accounting for imperfect detection and uncertainty in the local population sizes. The colonization probability increased with increasing connectivity and the local extinction probability decreased with increasing local population size in accordance with metapopulation theory. The local population size increased with increasing patch area, and was also affected by grazing intensity. Light grazing resulted in larger local populations compared to heavy grazing or no grazing at all. The butterfly population has decreased considerably during the study period and according to projections of future dynamics the estimated extinction risk within the coming 10years is 17%. However, it is possible to change the negative trends and decrease the extinction risk considerably by conservation actions. By optimizing the grazing pressure in existing patches the extinction risk was reduced to 11% (a reduction with 35% compared to the scenario with no conservation action). If a few new patches are created close to the occupied ones the extinction risk can be reduced further. In conclusion, there is a large risk that the Clouded Apollo butterfly will go extinct from southern Scandinavia within the coming decade. However, conservation measures that are focused to the core area of the current distribution and applied soon can considerably improve the situation for the butterfly.

Formulation Evaluation and Optimization of Proniosome Based Transdermal Patches of Ketorolac

Proniosomes are dry detailing of water-solvent bearer particles that are covered with surfactant and can be apportioned as required and dried out to frame niosomal scattering promptly before use on brief disturbance in hot fluid media inside of minutes. They have potential applications in the conveyance of hydrophobic and hydrophilic medications. Diverse clusters of proniosomes of Ketorolac tromethamine were readied by coacervation stage detachment strategy with distinctive proportions of polymers and surfactants. The physicochemical similarity of the medication and the polymers was considered by FTIR and DSC. The outcomes acquired demonstrated no physical-compound incongruently between the medication and the polymers. The readied frameworks were portrayed for embodiment effectiveness, shape, size and in vitro medication discharge. Release study was completed to research the draining of medication from the proniosomal framework amid capacity. On the premise of results acquired the gel KP 4 was upgraded and further utilized for the creation of transdermal patches with a backing layer (4% PVA) and a suitable rate controlling film. Distinctive rate controlling layers were readied with Eudragit RS-100 (ERS), Eudragit RL-100 (ERL) by mercury substrate method. The formulations were created and subjected to different physicochemical assessments and in vitro study. The patch manufactured with ERS (KTP 1) as rate controlling film was advanced as the best fix and further assessed for in vivo pervasion in rats. Investigation was completed to guarantee the connection between the in vitro and in vivo discharge design. The study exhibited that proniosomal transdermal patch in view of the ERS layer controlled discharge framework has the potential to deliver ketorolac tromethamine.

Landscape effects on jay foraging behavior decrease acorn dispersal services in dehesas

Dehesas are savanna-like, oak woodlands with a high conservation value that are threatened by chronic regeneration failure. Acorn dispersal by Eurasian jays (Garrulus glandarius) is vital for oak recruitment although jay preference for continuous forests may condition this mutualism in dehesas. In this study, we evaluated whether the acorn dispersal services provided by jays to oaks differed between both habitats and assessed factors that could potentially drive such differences. We (1) monitored acorn removal rates at feeders located close to focal trees in a holm oak (Quercus ilex) forest and in a nearby dehesa over a 6-year period; (2) measured the spatial traits of focal trees and their acorn production; and (3) monitored dispersal distances and microhabitat selection for acorn caching during 2012.Our results indicated that jays were able to exploit dehesas located close to forest habitats, but did so infrequently and as a secondary food source (acorn removal rates were six times lower in dehesa than in nearby forests). This likely occurred because dehesas did not offer new or more abundant food sources on a landscape scale. In forests, tree choice was driven by crop traits while in dehesas it was driven by spatial location. Jays preferentially foraged at dehesa trees near forest patches and aggregated to other trees, regardless of crop traits. Acorns were mobilized four times closer in dehesas, and seeds were preferentially cached in unsuitable microhabitats for seedling establishment. Our results suggest that (i) distance to forest habitats and tree isolation effects on jay foraging behavior reduces their dispersal services in dehesas as compared to nearby forests, and (ii) practices designed to enhance acorn dispersal by jays in this habitat should focus on the maintenance or creation of forest patches interspersed within dehesa areas.

Live coral cover may provide resilience to damage from the vermetid gastropod Dendropoma maximum by preventing larval settlement

Dendropoma maximum is a vermetid gastropod (a sessile tube-forming snail) commonly associated with living corals throughout shallow-water reefs of the Indo- Pacific. Recent work suggests that, once established, this species can adversely affect growth and survival of corals. Here, we test the hypotheses that disturbances to live coral substrates (e.g., creation of bare patches) facilitate suc- cessful larval settlement and subsequent population growth of D. maximum, and conversely, that live coral inhibits D. maximum settlement. In the shallow lagoon of Moorea, French Polynesia, we selected patch reefs where D. maxi- mum was either present or absent (to evaluate potential effects of resident adult conspecifics on recruitment) and established focal quadrats on each reef. In each quadrat, we either experimentally removed 50 % of live coral cover or left the quadrat with 100 % live coral cover. In addition, we deployed units of bare substrate (coral rubble) to each reef. We conducted a census of deployed substrates and quadrats after 6 months and found that D. maximum settled irrespective of resident vermetid populations, and only onto nonliving surfaces (i.e., cleared patches in quadrats, coral rubble, and marine epoxy). In laboratory experiments, we exposed larvae of D. maximum to live coral and found species-specific effects on survival of D. maximum larvae. Porites lobata and Pocillopora sp. killed larvae of D. maximum, Porites rus caused weaker mortality, and Millepora sp. had no effect on larval survival. Collectively, these results suggest that D. maximum requires distur- bances that create bare patches to successfully settle onto reefs, and that a high cover of living corals contributes resilience to reefs by limiting settlement opportunities of a species known to reduce coral growth and survival.

Cruciate Fenestration in Ventricular Septal Defect Patch for High-Risk Patients With High Pulmonary Vascular Resistance.

Late presentation of patients with large ventricular septal defect (VSD) and elevated pulmonary vascular resistance (PVR) is not uncommon in developing countries. Surgical VSD closure in these patients carries risks of persistent pulmonary hypertension, right ventricular failure, and mortality. Several techniques for creation of valved patches or fenestrated patches have been developed to address these issues. We have successfully used a simple and easily reproducible technique in which a cruciate fenestration is created in the patch used for VSD closure.

Disturbance accelerates the transition from low- to high-diversity state in a model ecosystem.

The effect of disturbance on a model ecosystem of sessile and mutually competitive species [Mathiesen et al., Phys. Rev. Lett. 107, 188101 (2011); Mitarai et al., Phys. Rev. E 86, 011929 (2012)] is studied. The disturbance stochastically removes individuals from the system, and the created empty sites are recolonized by neighboring species. We show that the stable high-diversity state, maintained by occasional cyclic species interactions that create isolated patches of metapopulations, is robust against small disturbance. We further demonstrate that finite disturbance can accelerate the transition from the low- to high-diversity state by helping the creation of small patches through diffusion of boundaries between species with standoff relations.