Long-distance Dispersal Research Articles

Construction of CuCoCe ternary catalyst via a porous organic polymer template approach for efficient CO-PROX with wide operating temperature window

Preferential CO oxidation (CO-PROX) is a promising approach for removing trace CO from hydrogen-rich streams, effectively preventing Pt anode poisoning in proton-exchange membrane fuel cells (PEMFCs). To effectively eliminate CO within the PEMFC operating temperature range, catalysts must exhibit high CO conversion and O2 selectivity. Expanding the operating temperature window of these catalysts is crucial. This study presents the synthesis of a CuCoCe ternary catalyst (CuCo/Ce-P) using an imidazole-functionalized porous organic polymer as a sacrificial template. Compared to the CuCoCe ternary catalyst prepared without a template (CuCo/Ce), CuCo/Ce-P exhibits significantly enhanced catalytic activity, with a T50 reduction from 85 °C to 55 °C and an expanded operating temperature window of approximately 40 ℃. Characterization results indicate that the imidazole-functionalized porous organic polymer facilitates improved dispersion of active species by anchoring metal ions through electron-rich groups, enhances intermetallic interactions, promotes electron transfer, and significantly improves the oxygen-deficient capacity of the CuCoCe ternary catalyst. Consequently, the catalyst exhibits a greater number of active interfaces, leading to enhanced catalytic activity and a wider operating temperature window.

Influence of habitat management and selected environmental parameters on the ground-living communities of harvestmen (Opiliones) in the historical park in Rusovce (Slovakia)

City parks serve as valuable refuges for invertebrates in the urban environment, which are constantly exposed to human influence caused by management practices in the parks. Many harvestman species are suitable bioindicators for monitoring ecological change; however, their effective use in environmental assessment necessitates to expand the insufficient knowledge of ecological environmental specificities of their communities. We studied the diversity and dynamics of harvestman (Opiliones) communities in the historical park in Rusovce, situated in the southwestern part of Bratislava (Slovakia). Seven study sites were investigated, representing areas subjected to different management practices. The research was conducted from March 2019 to April 2020, using pitfall traps. We evaluated the impact of microclimatic variables (soil and air temperature), environmental characteristics (plant diversity and cover of vegetation layers, age of forest stands, thickness of the litter layer), and management practices on the structure of harvestman communities. The study revealed the response of specific harvestman species to temperature variations, emphasizing the importance of microclimatic conditions. Environmental variables, such as the richness of plant species in the shrub layer, the cover of the herb and shrub vegetation layers, and the age of the forest stands, were identified as key factors that influence the dispersal of harvestman species. Furthermore, management practices, especially the presence of monoculture tree plantations, significantly affected the species composition of harvestmen. Examining the sensitivity of Opiliones, important bioindicators, to these factors is crucial for implementing effective conservation strategies in urban green spaces and anthropogenically influenced ecosystems.

Likelihood Ratio Test For The Multivariate Normal Generalized Variance

An interesting measure of variability in multivariate populations is the determinant of the covariance matrix Σp×p, denoted as |Σ|, commonly referred to as generalized variance. This measure succinctly captures the dispersion of a multivariate population into a single value, while accounting for inter-variable dependencies. Consequently, it finds applications across various domains concerned with assessing dispersion within multivariate populations of interest. In this study, we introduce a likelihood ratio test for the generalized variance of multivariate normal distributions, accompanied by a theoretical exposition on the distribution theory of sample generalized variances. We propose both the Likelihood Ratio Test (LRT) and the Bartlett-Corrected Likelihood Ratio Test (BCLRT) for assessing the hypothesis that the generalized variance equals a parameter η, where η ∈ R. The development of these tests is purely theoretical. Our recommendation is to employ the BCLRT test primarily in scenarios where p = 2, particularly when n > 30. As for the LRT test, we suggest its application in cases where p = 2 or p = 3, provided that n > 30, and for p = 5 when n > 50.

Mitochondrial DNA patterns describe the evolutionary history of the bonnethead shark Sphyrna tiburo (Linneus 1758) complex in the western Atlantic Ocean.

The apparent lack of physical barriers in the marine realm has created the conception that many groups have a constant gene flow. However, changes in ocean circulation patterns, glacial cycles, temperature, and salinity gradients are responsible for vicariant events in many fish species, including sharks. The bonnethead shark, Sphyrna tiburo, is an endangered small coastal shark species. Although considerable efforts have recently been undertaken, little remains known about the possible biogeographic scenario that can explain its actual distribution within the western Atlantic (WA). Here, we used 599 mitochondrial sequences to assess the phylogeographic structure and implement Bayesian phylogenetic analyses to obtain divergence times and reconstruct the ancestral geographic range. This allowed us to infer processes responsible for the diversification of S. tiburo into major divergent lineages. Our results indicated that S. tiburo in the WA represents three independent lineages, with Brazilian samples differentiated into a distinct genetic cluster. The posterior probability of ancestral range analysis indicated that the species likely originated in the northern region (Carolina Province and the southern Gulf of Mexico), where it colonized southward through the uplifting of the Central American Isthmus (CAI). The Northern and Caribbean genetic clusters appear to have arisen from the intensification of the Loop Current, which currently flows northward passing the Yucatan Peninsula, Gulf of Mexico, and east Florida. Following initial colonization, the Northeastern Brazil group differentiated from the Caribbean region due to the sediment and freshwater discharge of the Amazon-Orinoco Plume. Thus, the evolutionary history of the S. tiburo complex can be explained by a combination of dispersal and vicariance events that occurred over the last ~5 million years (MY). We established and confirmed the species and population limits, demonstrating that the Amazon-Orinoco Plume constitutes a significant dispersal barrier for coastal sharks. Finally, we discuss some recommendations for the conservation of the bonnethead shark.

Confidence Interval Estimating the Mean of Normal Distribution and Skewed Distribution

The confidence interval is an important statistical estimator of population location and dispersion parameters. The purpose of this paper is to comprehend CI utilising various techniques. This includes classical CI, percentile bootstrap method, bootstrap-t and proposed bootstrap-t decile mean method. Distributions that are skewed and normal are used to generate data. The efficiency of the proposed method is evaluated on the basis of an extensive simulation study. The simulation findings show that the performance of the Student-t and three bootstrap approaches varies dramatically depending on sample size and skewness type. The coverage probability and length of the proposed confidence interval are compared with certain existing and widely used confidence intervals. For illustrative purposes, two real-life data sets are analysed, which, to some extent, support the simulation study conclusions. This paper's findings will be useful to a variety of researchers with practical experience in the fields of science and social sciences.

Prevalence and Genetic Diversity of Deer Tick Virus (Powassan Virus, Lineage II) in Ixodes scapularis Ticks in Five Habitats at a Nature Reserve in Southern Maine, United States.

Deer tick virus (DTV), also known as Powassan virus lineage II, is a rising health concern due to increased recognition as a cause of human encephalitis. Since European tick-borne encephalitis virus persists in nature in enzootic foci (i.e., higher prevalence rates in small pockets in nature), we sought to determine whether DTV is also focally maintained in relation to habitat type, to better understand factors leading to human risk of exposure. From 2018 to 2021, questing Ixodes scapularis ticks were collected from five habitats at the Wells National Estuarine Research Reserve (WNERR) in Wells, ME: forest with invasive vegetation in the understory, edge, shrub, forest with native vegetation in the understory, and open field. Deer tick virus prevalence was greater in adult ticks (2.0%) than in nymphs (0.5%). Deer tick virus prevalence in adult ticks collected from forest with invasive vegetation was 3.2% compared to 0 to 1.7% in other habitat types. A hot spot analysis revealed a higher number of infected adults collected per hour on one of the transects located in forest with invasive vegetation. Phylogenetic analysis of 37 full-length DTV genomes sequenced in this study revealed four major clades from the WNERR, and there was high genetic diversity within each transect, suggesting frequent, short-range dispersal between habitats. Analysis of DTV sequences from other New England counties and states also indicated long-distance dispersal to and/or from the WNERR. This study provides preliminary evidence that DTV is focal and that the risk of encountering DTV-infected ticks in forest with invasive vegetation may be greater than in other habitat types.

Highly Dispersed Pd@ZIF‐8 for Photo‐Assisted Cross‐Couplings and CO2 to Methanol: Activity and Selectivity Insights

AbstractOur study unveils a pioneering methodology that effectively distributes Pd species within a zeolitic imidazolate framework‐8 (ZIF‐8). We demonstrate that Pd can be encapsulated within ZIF‐8 as atomically dispersed Pd species that function as an excited‐state transition metal catalyst for promoting carbon–carbon (C−C) cross‐couplings at room temperature using visible light as the driving force. Furthermore, the same material can be reduced at 250 °C, forming Pd metal nanoparticles encapsulated in ZIF‐8. This catalyst shows high rates and selectivity for carbon dioxide hydrogenation to methanol under industrially relevant conditions (250 °C, 50 bar): 7.46 molmethanol molmetal−1 h−1 and >99 %. Our results demonstrate the correlations of the catalyst structure with the performances at experimental and theoretical levels.

The Final Pliocene and Early Pleistocene Faunal Dispersals from East to Europe and Correlation of the Villafranchian Biochronology between Eastern and Western Europe

The Villafranchian stage in the mammal fauna evolution in Eurasia (ca. 3.6/3.4 Ma—ca. 1.2 Ma) is associated with the beginning of the formation of the modern appearance of the mammal megafauna of today’s Palaearctic. The cooling and the aridification starting with the beginning of the Early Pleistocene gradually eliminated the quasi-tropical appearance of the Late Neogene landscapes and fauna of Europe. The time from the Mid-Piacenzian (ca. 3.3–3.0 Ma) to the end of the Early Pleistocene was a time of particularly intense dispersal of species, of faunal exchange between Eurasia and Africa, and of the entry of new mammals into Europe from the East. That is why the correlation of the biochronology of the Villafranchian fauna between Eastern and Western Europe is of particular interest. Accumulated data make possible a more precise correlation of these faunas today. A correlation of selected Eastern European localities with established faunal units and MNQ zones is made in the present work. Usually, the dispersal from Asia or from E. Europe to W. Europe is instantaneous from a geological point of view, but in a number of cases, reaching W. Europe happens later, or some species known to be from Eastern Europe do not reach Western Europe. The main driving forces of the faunal dispersals, which are the key bioevents in the faunal formation, are climate changes, which in turn, affect the environment. We can summarize the following more significant Villafranchian bioevents in Europe: the End Pliocene (Early Villafranchian: MNQ16) turnover related to the first appearance of a number of taxa, for example, felids, canids, proboscideans, and ungulates; the Quaternary beginning turnover. Correlated with this are the beginning of the Middle Villafranchian, which should be placed at about 2.6 Ma; the Coste San Giacomo faunal unit turnover (Senèze and Slivnitsa localities should be included here, and the FU itself, at the very beginning of the late Villafranchian (=MNQ18a)); the Pachycrocuta event at the very beginning of the Olivola FU; and the events related to the Late Villafranchian/Epivillafranchian bounfary.

Diversity, divergence time, and biogeography of the genus Albatrellus (Agaricomycetes, Russulales)

ABSTRACT The genus Albatrellus is an important group of stipitate terrestrial fungi in the order Russulales. Some species in the genus form ectomycorrhizae, mostly with trees of Pinaceae; some are well-known edible mushrooms. However, its diversity and biogeography are unclear. Taxonomic and phylogenetic studies on Albatrellus were carried out by morphological examination, which included detailed observations of the fruiting body, spore shape and size, and other key features, together with potential hosts. These observations were then compared and analysed using multi-locus molecular phylogenetic analyses, including the internal transcribed spacer regions (ITS), the large subunit nuclear ribosomal RNA gene (nLSU), the translation elongation factor 1-α gene (tef1), the largest subunit of RNA polymerase II (rpb1), the second largest subunit of RNA polymerase II (rpb2), the small subunit mitochondrial rRNA gene (mtSSU), and the small subunit of the nuclear ribosomal RNA gene (nucSSU). The results demonstrated that the species of Albatrellus formed eight clades. Nine new species are described and illustrated, and two new combinations are proposed. A total of 38 species are accepted in Albatrellus worldwide. Of those species, 26, 7, and 8 species are distributed in Asia, Europe, and North America, respectively. The divergence time indicated that the maximum crown age of Albatrellus was approximately 70.5 million years ago, and East Asia and North America are the likely ancestral areas. Dispersal and differentiation to other continents occurred during the late Paleocene and Miocene. Three kinds of dispersal routes are proposed: East Asia and Europe, East Asia and North America, and Europe and North America.

Developing a Calculation Workflow for Designing and Monitoring Urban Ecological Corridors: A Case Study

Urban ecological corridors play a crucial role in biodiversity conservation, connecting fragmented habitats in highly anthropized areas and generating benefits in terms of the sustainability of urban environments. These corridors mitigate the effects of habitat fragmentation, such as reduced genetic diversity and limited species dispersal, while improving the ecological health of urban environments and the well-being of citizens. This study proposes a calculation workflow for the identification of the necessary and most suitable ecological corridors to be planned in the urban-environmental planning phase and identifies some of the existing innovative technologies to evaluate and improve their functionality, enabling the real-time monitoring of habitat conditions and providing valuable information to optimize the design and management of these peri-urban natural areas. Urban ecological corridors also improve human well-being by contributing to cleaner air, better water quality and recreational opportunities to the point that the costs incurred for their construction are much lower than the economic and social benefits for the area.

Evidence of a European seed dispersal crisis.

Seed dispersal is crucial for ecosystem persistence, especially in fragmented landscapes, such as those common in Europe. Ongoing defaunation might compromise effective seed dispersal, but the conservation status of pairwise interactions remains unknown. With a literature review, we reconstructed the first European-wide seed dispersal network and evaluated the conservation status of interactions by assessing each interacting partner's IUCN (International Union for Conservation of Nature) conservation status and population trends. We found that a third of the disperser species and interactions face potential extinction and that 30% of the plant species have most of their dispersers threatened or declining. Our study reveals a developing seed dispersal crisis in Europe and highlights large knowledge gaps regarding the dispersers and conservation status of zoochorous plants, urging further scrutiny and action to conserve the seed dispersal service.

Avian diversity across guilds in North America versus vegetation structure as measured by the Global Ecosystem Dynamics Investigation (GEDI)

Avian diversity, a key indicator of ecosystem health, is closely related to canopy structure. Most avian diversity models are based on either optical remote sensing or airborne lidar data, but the latter is limited to small study areas. The launch of the Global Ecosystem Dynamics Investigation (GEDI) instrument in 2018 has opened new avenues for exploring the influence of vegetation structure on avian diversity. To examine how direct measurements of canopy structural characteristics explain bird diversity across North America, we analyzed 18 GEDI metrics from 2019 to 2022, along with corresponding Breeding Bird Survey (BBS) counts and AVONET morphological data, analyzing effects across broad regions and at varying spatial extents. We grouped 440 bird species into 20 ecological guilds under six guild categories and employed random forest algorithms to model avian diversity across eight spatial extents (1, 2, 3, 4, 5, 10, 20, and 39.2 km). The models predicted six diversity indices, including species richness (sRich), functional richness (fRich), evenness (fEve), dispersion (fDis), divergence (fDiv), and redundancy (fRed) across eight spatial extents. The best-predicted guilds varied for each diversity index. The most accurate models were sRich (pseudo-R2 = 0.71, RMSE = 4.28) and fRed (pseudo-R2 = 0.60, RMSE = 0.13) for forest specialists guilds; fRich (pseudo-R2 = 0.55, RMSE = 0.18) for urban guilds; fEve (pseudo-R2 = 0.28, RMSE = 0.08) for insectivore guilds; and fDiv (pseudo-R2 = 0.38, RMSE = 0.12) and fDis (pseudo-R2 = 0.53, RMSE = 0.87) for short distance migrants guilds. Our results highlight the critical role of canopy structure, including its horizontal and vertical distribution and variation, in predicting avian diversity, as measured by the mean number of detected modes (num_detectedmodes), the standard deviation of foliage height diversity (FHD), num_detectedmodes, canopy cover, and plant area index (PAI) across the spatial extents centered on BBS routes. Therefore, we recommend incorporating the GEDI metrics into avian diversity modeling and mapping across North America, thereby potentially enhancing bird habitat management and conservation efforts.

Catalytic functionalization of MCM-41 and MCM-48 with copper by modified template ion-exchange method for low-temperature NH3-SCR process: the role of complexing agents for copper dispersion

Mesoporous silicas of MCM-41 and MCM-48 types were synthesized and modified with copper by template ion-exchange (TIE) technique. A high dispersion of deposited copper species was managed by subsequent treatment of the samples with ammonia, urea, or acetonitrile solution. Copper-modified silicas were analysed in terms of their chemical composition (ICP-OES), ordering of porous structure (XRD), textural parameters (low-temperature N2 sorption), dispersion and form of introduced copper species (UV–vis-DR, XRD, H2-TPR, NH3-TPD). Mesoporous silicas modified with copper exhibited promising catalytic efficiency in selective catalytic reduction of NO with ammonia (NH3-SCR). The samples containing dispersed copper species (predominantly monomeric copper cations) presented enhanced catalytic activity compared to catalysts containing CuO aggregates. On the other hand, CuO aggregates showed greater catalytic activity in the side process of direct ammonia oxidation by oxygen present in the reaction mixture. It was demonstrated that TIE post-treatment of the samples with urea resulted in most effective improving dispersion of deposited copper and is less destructive for ordered porous structures of mesoporous silica comparing to treatment with ammonia solution.Graphical abstract

Alasemenia, the earliest ovule with three wings and without cupule.

The ovules or seeds (fertilized ovules) with wings are widespread and especially important for wind dispersal. However, the earliest ovules in the Famennian of the Late Devonian are rarely known about the dispersal syndrome and usually surrounded by a cupule. From Xinhang, Anhui, China, we now report a new taxon of Famennian ovules, Alasemenia tria gen. et sp. nov. Each ovule of this taxon possesses three integumentary wings evidently extending outwards, folding inwards along abaxial side and enclosing most part of nucellus. The ovule is borne terminally on smooth dichotomous branches and lacks a cupule. Alasemenia suggests that the integuments of the earliest ovules without a cupule evolved functions in probable photosynthetic nutrition and wind dispersal. It indicates that the seed wing originated earlier than other wind dispersal mechanisms such as seed plume and pappus, and that three- or four-winged seeds were followed by seeds with less wings. Mathematical analysis shows that three-winged seeds are more adapted to wind dispersal than seeds with one, two or four wings under the same condition.

Alasemenia, the earliest ovule with three wings and without cupule

The ovules or seeds (fertilized ovules) with wings are widespread and especially important for wind dispersal. However, the earliest ovules in the Famennian of the Late Devonian are rarely known about the dispersal syndrome and usually surrounded by a cupule. From Xinhang, Anhui, China, we now report a new taxon of Famennian ovules, Alasemenia tria gen. et sp. nov. Each ovule of this taxon possesses three integumentary wings evidently extending outwards, folding inwards along abaxial side and enclosing most part of nucellus. The ovule is borne terminally on smooth dichotomous branches and lacks a cupule. Alasemenia suggests that the integuments of the earliest ovules without a cupule evolved functions in probable photosynthetic nutrition and wind dispersal. It indicates that the seed wing originated earlier than other wind dispersal mechanisms such as seed plume and pappus, and that three- or four-winged seeds were followed by seeds with less wings. Mathematical analysis shows that three-winged seeds are more adapted to wind dispersal than seeds with one, two or four wings under the same condition.

Active restoration after three decades: Seed addition increases native dominance compared to landscape‐scale secondary succession

Abstract Active restoration often aims to accelerate ecosystem recovery. However, active restoration may not be worthwhile if its effects are overwhelmed by changes that occur passively. Moreover, it can be challenging to separate the effects of passive processes, such as dispersal and natural succession, from active restoration efforts. We assess the 24‐year impact of actively restoring a Minnesota old‐field grassland via seed addition of native tallgrass prairie species. We compared the abundance of four functional plant groups in actively restored plots against abundances in three reference classes: (1) unrestored plots undergoing passive recovery within the same old field, (2) passively recovering plots in two nearby old fields of similar age and (3) a chronosequence of 21 old fields within the same landscape. Active restoration led to a higher abundance of native grasses and forbs in the 36 m2 treatment plots. Seed addition was more effective if the original vegetation was first removed using herbicide, burning and tilling. However, long‐term conclusions about the efficacy of active restoration varied widely depending on the choice of reference class. In our small‐scale restoration experiment, native abundance was similarly high in both the actively restored and reference plots after 24 years, suggesting either (1) passive recovery or (2) local dispersal of native species from nearby treatment plots (i.e. cross‐contamination). In contrast, a comparison with two nearby reference fields suggested active restoration resulted in much higher native abundance relative to passive recovery. A smaller, positive effect was detected when we compared actively restored plots to the chronosequence of old fields. In the chronosequence, many passively recovering old fields had transitioned to native grass dominance naturally, although active restoration appeared to increase native forb abundance. Synthesis and applications: Our findings highlight the importance of using scale‐appropriate references for assessing the efficacy and need for active restoration. Comparing actively restored plots with the surrounding landscape, we found that active restoration and passive recovery led to similar plant communities after 24 years. Because local dispersal from actively restored sites can nearby references, caution should be exercised when evaluating long‐term restoration projects using only small‐scale experiments.

Spatio‐temporal variability in seed production of tree species: implications for restoration in the Cerrado–Amazonia transition zone

The use of propagules collected in ecotonal regions for restoration purposes is challenging because of the mix of species from different vegetation types and reproductive phenological variability. We used a database of the Xingu Seed Network in Brazil, which contains data on 139 native tree species for 8 years (2011–2018) in the Cerrado–Amazonia transition zone, to answer three questions: (1) What is the spatio‐temporal variability in the seed dispersal of tree species, and how does it relate to the species' preferential habitat? (2) Is there a relationship between the seed dispersal period and climate variables? (3) Is the frequency of tree species with different dispersal syndromes equally distributed among biomes and seed‐size classes? Independent of their preferred ecosystem (Amazonia or Cerrado), some species showed substantial spatio asynchrony in fruit dispersal, extending the dispersal period at a regional scale. The seed dispersal period was strongly correlated (rs > 0.6) with precipitation and minimum or maximum air temperature in 41% (n = 57) of the studied species. We showed that three‐quarters of the species (n = 105) dispersed seeds in the late dry and early rainy periods, with little variation among dispersal syndromes. Our findings will enhance the effectiveness of restoration initiatives by increasing the accuracy of predictions of the location and time for collecting seeds in the extensive Cerrado–Amazonia transition zone.

Specialized seed dispersal in Neotropical Vanilla reveals fruit unpalatability to omnivores.

Flowering plants are essentially sessile organisms that disperse their genes through pollination, expanding their areas of occurrence through seed dispersal. In orchids, seed dispersal is commonly mediated by air currents. Conversely, members of several genera have evolved seeds adapted to endozoochory. This is the case for Vanilla, the most economically important genus in the orchid family. The role of indehiscent fruits in the attraction and rewarding of Vanilla seed dispersers was investigated based on field observations, analysis of fragrances, reward substances, and investigation of seed viability through the digestive tract. Indehiscent Vanilla fruits are consumed exclusively by herbivores, i.e. agoutis. Besides providing nutritional rewards, the fruits are rich in polyphenols that are unpalatable to omnivores. The most dominant compound in fruits is attractive only to agoutis. This is the first study showing synzoochory in Orchidaceae and specificity of seed dispersal in orchids. Indehiscent fruits may have evolved early in Neotropical Vanilla in response to selection pressures mediated by large herbivores as the genus emerged ca. 34 Mya in South America, concomitantly with megafauna diversification in the Oligocene. Extinction of the megafauna during the Pleistocene has left agoutis as inheritors of seed dispersal in species with large fleshy fruits. Apart from the effects on omnivores, this study shows that indehiscent fruits of V. chamissonis are consumed exclusively by agoutis, providing the first evidence of target mutualism in orchid seed dispersal.

Cultural rhythms and pulses on MIS 5-3 migration episodes of Homo sapiens dispersal in Northeast Africa

On the one hand, genetic observations suggest one essential migration of anatomically modern humans (AMH) from Africa to Eurasia had taken place around 70-50 ka BP and led to the dispersal of AMH all over the world (Out-of-Africa-II model). On the other hand, given the initial phase of the migration would have been located in East and Northeast Africa, archaeological patterning of cultural traits can, so far, neither support nor contradict such a model within the supposed area of migration, and at the time concerned hereby. This paper addresses the obvious invisibility of the migration in the archaeological record and the reasons for it. We propose the summer/winter rainfall frontier to have caused phases of isolation between East and Northeast Africa, impeding cultural exchange between these areas, either resulting from acculturation or migration. We exclude large scale events of dispersal, only small-scale movements of populations to be admitted. This might explain the lack of archaeological visibility of the migration event.

Exploring Floristic Diversity, Propagation Patterns, and Plant Functions in Domestic Gardens across Urban Planning Gradient in Lubumbashi, DR Congo

Urbanization degrades natural habitats and creates new urban ecosystems like domestic gardens. The plant composition of these gardens varies with socio-economic factors and urban planning levels. However, the diversity and impact of introduced species are often poorly assessed, causing potential ecological imbalances (disruptions in the natural functioning and stability of ecosystems), particularly in Lubumbashi (DR Congo). The objective was to analyze the spatial structure, plant diversity, propagation strategies, and ecological functions of domestic gardens. Three distinct neighborhoods were selected: a planned, unplanned, and residential neighborhood. Twenty avenues (with five plots per avenue) were chosen to represent the diversity within each neighborhood, and stratified random sampling of plots was conducted to analyze gardening practices. Gardens were classified into types, and their vegetation was evaluated based on species origin and ecological impact. The analysis of domestic gardens in Lubumbashi reveals significant variations across different neighborhood types. Residential neighborhoods exhibit larger average garden sizes (315.1 m2), higher species richness (22 species), and larger plot sizes (1032 m2) compared to unplanned and planned neighborhoods, where garden areas and species richness are notably lower. Rectangular gardens dominate in unplanned areas, while planned neighborhoods feature more intentional landscaping elements, such as flowerbeds and hedges. The use of gardens for food production is prominent in planned areas (40.7%), whereas residential neighborhoods prioritize ornamentation (51.4%). The study identified 232 taxa across 68 families, with a predominance of exotic species (80%) in all neighborhoods, particularly in unplanned areas (82.25%). The data revealed that Mangifera indica and Persea americana are abundant in all neighborhoods, illustrating their adaptability to different urban contexts. Herbaceous species are most common, followed by woody plants, with vines being sparse. Species dispersal is primarily driven by human activities (anthropochory), accounting for over 85% in all neighborhoods. These findings highlight the strong human influence on the composition and structure of domestic gardens in Lubumbashi, emphasizing the dominance of exotic species and the importance of anthropogenic factors in shaping urban green spaces. Urban policies should incorporate strategies to minimize the negative impacts of exotic species on native flora.