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Results for “Spatial niche”

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PubMed2004

Ecophysiological interaction between nitrifying bacteria and heterotrophic bacteria in autotrophic nitrifying biofilms as determined by microautoradiography-fluorescence in situ hybridization.

Ecophysiological interactions between the community members (i.e., nitrifiers and heterotrophic bacteria) in a carbon-limited autotrophic nitrifying biofilm fed only NH(4)(+) as an energy source were investigated by using a full-cycle 16S rRNA approach followed by microautoradiography (MAR)-fluorescence in situ hybridization (FISH). Phylogenetic differentiation (identification) of heterotrophic bacteria was performed by 16S rRNA gene sequence analysis, and FISH probes were designed to determine the community structure and the spatial organization (i.e., niche differentiation) in the biofilm. FISH analysis showed that this autotrophic nitrifying biofilm was composed of 50% nitrifying bacteria (ammonia-oxidizing bacteria [AOB] and nitrite-oxidizing bacteria [NOB]) and 50% heterotrophic bacteria, and the distribution was as follows: members of the alpha subclass of the class Proteobacteria (alpha-Proteobacteria), 23%; gamma-Proteobacteria, 13%; green nonsulfur bacteria (GNSB), 9%; Cytophaga-Flavobacterium-Bacteroides (CFB) division, 2%; and unidentified (organisms that could not be hybridized with any probe except EUB338), 3%. These results indicated that a pair of nitrifiers (AOB and NOB) supported a heterotrophic bacterium via production of soluble microbial products (SMP). MAR-FISH revealed that the heterotrophic bacterial community was composed of bacteria that were phylogenetically and metabolically diverse and to some extent metabolically redundant, which ensured the stability of the ecosystem as a biofilm. alpha- and gamma-Proteobacteria dominated the utilization of [(14)C]acetic acid and (14)C-amino acids in this biofilm. Despite their low abundance (ca. 2%) in the biofilm community, members of the CFB cluster accounted for the largest fraction (ca. 64%) of the bacterial community consuming N-acetyl-D-[1-(14)C]glucosamine (NAG). The GNSB accounted for 9% of the (14)C-amino acid-consuming bacteria and 27% of the [(14)C]NAG-consuming bacteria but did not utilize [(14)C]acetic acid. Bacteria classified in the unidentified group accounted for 6% of the total heterotrophic bacteria and could utilize all organic substrates, including NAG. This showed that there was an efficient food web (carbon metabolism) in the autotrophic nitrifying biofilm community, which ensured maximum utilization of SMP produced by nitrifiers and prevented buildup of metabolites or waste materials of nitrifiers to significant levels.

Autoradiography↗

PubMedDate not supplied

[The ecology of the sibling species Microtus arvalis Pallas, 1779 and Microtus rossiaemeridionalis Ognev, 1924 (Rodentia, Cricetidae) in the Tsimlianskie sands].

Ecological features and circadian activity of the common vole sibling species were studied upon joint and separate occurrences. Both species had a similar abundance but different biotopical distribution. Microtus arvalis--chromosome form "obscurus" populated the studied territory more uniformly the studied territory. M. rossiaemeridionalis tended to occur in humid coenoses. In case of joint occurrences, the sibling species occupied different regions of biotopes and the rhythms of their activity change, as a rule, in antiphase. Separation of the spatial and temporal niches of these species is considered as possible avoidance of competition between the closely related species.

Animals↗

PubMed2003

Direct visualization of transplanted hematopoietic cell reconstitution in intact mouse organs indicates the presence of a niche.

OBJECTIVE: The temporal and spatial behavior of transplanted hematopoietic stem cells (HSCs) within bones remains to be clarified. Our goal is to examine in vivo reconstitution processes and candidate niches in all bones in the mouse body using a new visualization method. MATERIALS AND METHODS: Using bone marrow cells from green fluorescent protein (GFP) transgenic mice, the reconstitution processes of transplanted hematopoietic cells (HCs) under myeloablative or nonmyeloablative conditions were observed sequentially from outside the bones with a fluorescent stereomicroscope. RESULTS: In case of myeloablative transplantation, GFP(+) spots were first detected at the epiphysis of femurs, and in some ribs and vertebrae among all intact bones. Thereafter, engrafted cells proliferated and spread into other bones. In case of nonmyeloablative transplantation with lin(-)Sca-1(+)c-kit(+) cells into W/Wv neonates, characterized by vacant niches because of stem cell defects, GFP(+) cells localized at the epiphysis of femurs and in some vertebrae and ribs, but not in all bones even 4 months after transplantation. CONCLUSION: Our findings show that transplanted HSCs or their immature progenies engraft preferentially at the epiphysis of the femurs or short and flat bones such as ribs and vertebrae. The transplanted cells remain quiescent for at least 4 months under nonmyloablative conditions, which implies the presence of stem cells in a niche. Our approach for the first time graphically demonstrates the kinetics of HCs in vivo and should facilitate analysis of HSC behavior in a three-dimensional mode.

Animals↗

PubMed2026

Advancing the Deciphering of Host-Microbe Crosstalk with Spatial Omics: A Mini-Review.

Host-microbe crosstalk refers to the reciprocal influences between a host and its resident or invading microorganisms. This crosstalk plays important roles in maintaining host health, regulating physiological functions, and coordinating responses to infection. The rapid rise of spatial omics is transforming how this crosstalk is studied in both animals and plants. Unlike traditional bulk omics, which homogenize tissues and erase spatial context, spatial methods preserve in situ organization and can simultaneously capture molecular information from hosts and microbes. As a result, researchers can characterize the spatial organization of colonization and infection, identify spatial associations between microbial niches and host cell states, and visualize local host response gradients across intact tissues. Current spatial omics technologies encompass sequencing-based, imaging-based, and hybrid platforms. Spatial multi-omics approaches enable the joint measurement or integration of gene expression, protein abundance, and metabolite distributions. Although spatial association alone does not establish causality, spatial omics provides a high-resolution framework for characterizing host-microbe relationships within intact tissues and generating spatially constrained, testable hypotheses. When combined with perturbation experiments and complementary experimental evidence, these hypotheses can contribute to mechanistic interpretation of host-microbe crosstalk. Here, we review spatial omics technologies, compare their suitability and major trade-offs for host-microbe studies, and discuss computational strategies, analytical challenges, and future prospects.

Multiomics↗

PubMed2005

Competition and coexistence between Streptococcus mutans and Streptococcus sanguinis in the dental biofilm.

The human mucosal surface is colonized by the indigenous microflora, which normally maintains an ecological balance among different species. Certain environmental or biological factors, however, may trigger disruption of this balance, leading to microbial diseases. In this study, we used two oral bacterial species, Streptococcus mutans and Streptococcus sanguinis (formerly S. sanguis), as a model to probe the possible mechanisms of competition/coexistence between different species which occupy the same ecological niche. We show that the two species engage in a multitude of antagonistic interactions temporally and spatially; occupation of a niche by one species precludes colonization by the other, while simultaneous colonization by both species results in coexistence. Environmental conditions, such as cell density, nutritional availability, and pH, play important roles in determining the outcome of these interactions. Genetic and biochemical analyses reveal that these interspecies interactions are possibly mediated through a well-regulated production of chemicals, such as bacteriocins (produced by S. mutans) and hydrogen peroxide (produced by S. sanguinis). Consistent with the phenotypic characteristics, production of bacteriocins and H2O2 are regulated by environmental conditions, as well as by juxtaposition of the two species. These sophisticated interspecies interactions could play an essential part in balancing competition/coexistence within multispecies microbial communities.

Adaptation, Biological↗

PubMed2026

Multi-omics identification and functional validation of signal regulatory protein gamma as a prognostic biomarker and immune regulator in head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) comprises biologically diverse tumors, and durable responses to immune-checkpoint blockade are achieved by only a subset of patients. There remains a need for markers that connect clinical outcome with malignant-cell phenotypes and tissue-level immune organization. METHODS: We integrated The Cancer Genome Atlas HNSCC cohort (TCGA-HNSC), five Gene Expression Omnibus (GEO) validation cohorts, single-cell RNA sequencing, Visium spatial transcriptomics, cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq)-informed protein-potential inference, pharmacogenomic screening, genetic-risk analysis and experimental validation. A reconstructed 296-pipeline survival modelling framework was used to prioritize prognostic hub genes across validation-cohort-specific analyses. RESULTS: SIRPG was repeatedly ranked among the top ten selected genes in all five validation cohorts. At single-cell resolution, SIRPG-high tumor cells showed stronger malignant-cell features, immune-inhibitory and metabolic programs, Scissor-positive risk association, CLCA2/P53-related perturbation signals and inferred SIRPG-CD47/signal regulatory protein (SIRP) communication. Spatial analyses placed this axis within an immune-checkpoint-coupled niche, supported by Maxspin/multiview intercellular spatial modelling (MISTy) spatial coupling, communication analysis by optimal transport (COMMOT)-inferred CD47-SIRPG communication and scProTrans-inferred CD47/SIRPG protein-potential overlap. Functionally, SIRPG knockdown reduced HNSCC cell viability and increased apoptosis, whereas re-expression of short hairpin RNA (shRNA)-resistant SIRPG restored the CLCA2-BAX/BCL2 protein response. CONCLUSION: Together, these findings identify SIRPG as an immune-related prognostic hub and context-dependent tumor-cell regulator associated with apoptosis, immune communication and spatial microenvironmental organization in HNSCC.

Humans↗

PubMed1997

Potential and distribution of transplanted hematopoietic stem cells in a nonablated mouse model.

Increasingly, allogeneic and even more often autologous bone marrow transplants are being done to correct a wide variety of diseases. In addition, autologous marrow transplants potentially provide an opportune means of delivering genes in transfected, engrafting stem cells. However, despite its widespread clinical use and promising gene therapy applications, relatively little is known about the mechanisms of engraftment in marrow transplant recipients. This is especially so in the nonablated recipient setting. Our data show that purified lineage negative rhodamine 123/Hoechst 33342 dull transplanted hematopoietic stem cells engraft into the marrow of nonablated syngeneic recipients. These cells have multilineage potential, and maintain a distinct subpopulation with "stem cell" characteristics. The data also suggests a spatial localization of stem cell "niches" to the endosteal surface, with all donor cells having a high spatial affinity to this area. However, the level of stem cell engraftment observed following a transplant of "stem cells" was significantly lower than that expected following a transplant of the same number of unseparated marrow cells from which the purified cells were derived, suggesting the existence of a "nonstem cell facilitator population," which is required in a nonablated syngeneic transplant setting.

Animals↗

PubMed2006

Using niche-based models to improve the sampling of rare species.

Because data on rare species usually are sparse, it is important to have efficient ways to sample additional data. Traditional sampling approaches are of limited value for rare species because a very large proportion of randomly chosen sampling sites are unlikely to shelter the species. For these species, spatial predictions from niche-based distribution models can be used to stratify the sampling and increase sampling efficiency. New data sampled are then used to improve the initial model. Applying this approach repeatedly is an adaptive process that may allow increasing the number of new occurrences found. We illustrate the approach with a case study of a rare and endangered plant species in Switzerland and a simulation experiment. Our field survey confirmed that the method helps in the discovery of new populations of the target species in remote areas where the predicted habitat suitability is high. In our simulations the model-based approach provided a significant improvement (by a factor of 1.8 to 4 times, depending on the measure) over simple random sampling. In terms of cost this approach may save up to 70% of the time spent in the field.

Algorithms↗

PubMed2026

Cardiomyocyte-Specific Plakophilin-2 Loss Is Sufficient to Induce Aging and Senescence of Nonmyocytes: Relevance to Arrhythmogenic Cardiomyopathy.

BACKGROUND: Pathogenic variants in PKP2 are the most common cause of familial arrhythmogenic right ventricular cardiomyopathy. This study tests whether plakophilin-2 (PKP2) deficiency only in cardiomyocytes is sufficient to provoke premature aging and proinflammatory senescence in nonmyocyte, cardiac resident cells. METHODS: We studied mice with cardiomyocyte-specific, tamoxifen-activated loss of PKP2 (cardiomyocyte-specific conditional knockout of plakophilin-2) using conventional and multiplex imaging, cytokine arrays, epigenetic clocks, spatial transcriptomics, expansion and structured illumination microscopy, and correlative data analysis. We examined nonmyocytes and cardiomyocytes for premature aging and senescence. RESULTS: We observed senescence-associated heterochromatin foci in nonmyocytes, predominantly in cells positive for α-smooth muscle actin staining. Cytokines in media of nonmyocyte cells were consistent with senescence-associated secretory phenotype. Epigenetic clocks identified premature aging. Multiplex immunohistochemistry showed nonmyocyte cells in niches, intermingled with cardiomyocytes. Spatial transcriptomics showed overrepresentation of senescence-associated secretory phenotype-related transcripts, predominantly in myocyte-rich areas of the left ventricle. Senescence-associated heterochromatin foci and increased epigenetic age were not found in cardiomyocytes from cardiomyocyte-specific conditional knockout of plakophilin-2 hearts, although we observed structural features associated with premature aging. Cross-reference analysis showed correlation between the cardiomyocyte-specific conditional knockout of plakophilin-2 cardiac proteome and that of mice 5 or 6 times their chronological age, as well as transcriptional signatures of neurodegenerative diseases. CONCLUSIONS: Loss of PKP2 expression only in adult cardiac myocytes is sufficient to induce proinflammatory senescence in nonmyocytes, and overall premature cardiac aging. This is the first study to intersect cellular senescence and premature aging with desmosomal arrhythmogenic cardiomyopathies. We speculate that cell-agnostic molecular signatures, biomarkers, and pharmacology of senescence and of neurodegenerative diseases may be relevant to diagnose or treat PKP2 arrhythmogenic right ventricular cardiomyopathy.

Animals↗

PubMed2026

GPNMB-directed CAR T cell therapy against MiT/TFE-family fusion-driven solid tumors.

Chimeric antigen receptor (CAR) T cell therapy for solid tumors is constrained by the scarcity of safe, uniformly expressed cell-surface targets. Here we identify glycoprotein NMB (GPNMB)-an MiT/TFE-family fusion-driven protein-as being highly, homogeneously and stably expressed in primary and relapsed alveolar soft-part sarcoma (ASPS) and translocation renal cell carcinoma. We develop a GPNMB-directed CAR T cell product, GCAR1, which demonstrates potent activity against patient-matched cells, organoids and xenograft models. Post hoc interim analysis of a first-in-human open-label, individual-participant trial ( NCT07104682 ) for a participant with relapsed/refractory, metastatic ASPS showed that GCAR1 induces stable disease for up to 3 months, accompanied by resolution of many nontarget lesions (primary endpoint), and is well tolerated. GCAR1 T cells expand in peripheral blood as a polyclonal population and remain detectable for 1 month. Spatial transcriptomics identified immunosuppressive niches in a treatment-resistant lesion and immune checkpoint blockade synergized with GCAR1 in a xenograft model. Altogether, our data provide a proof of concept for treating GPNMB-expressing solid tumors with GCAR1 and more broadly targeting surface antigens driven by oncogenic gene fusions with CAR T cell therapies.

Animals↗

PubMed2006

Nitrite concentration influences the population structure of Nitrospira-like bacteria.

Chemolithoautotrophic nitrite oxidizers of the genus Nitrospira are a monophyletic but diverse group of organisms, are widely distributed in many natural habitats, and play a key role in nitrogen elimination during biological wastewater treatment. Phylogenetic analyses of cloned 16S rRNA genes and fluorescence in situ hybridization with newly developed rRNA-targeted oligonucleotide probes revealed coexistence of uncultured members of sublineages I and II of the genus Nitrospira in biofilm and activated sludge samples taken from nitrifying wastewater treatment plants. Quantitative microscopic analyses of their spatial arrangement relative to ammonia oxidizers in the biofilm and activated sludge flocs showed that members of the Nitrospira sublineage I occurred significantly more often in immediate vicinity to ammonia oxidizers than would be expected from random community assembly while such a relationship was not observed for Nitrospira sublineage II. This spatial distribution suggested a niche differentiation of these coexisting Nitrospira populations with respect to their preferred concentrations of nitrite. This hypothesis was tested by mathematical modelling of nitrite consumption and resulting nitrite gradients in nitrifying biofilms and by quantifying the abundance of sublineage I and II Nitrospira in activated sludge during incubations with nitrite in different concentrations. Consistent with the observed localization patterns, a higher nitrite concentration selected for sublineage I but suppressed sublineage II Nitrospira.

Ammonia↗

PubMed2003

[Niches analysis of three aphid populations on spring sowing maize].

Systematic analysis of aphid populations and niches patterns on spring sowing maize was carried out during 1998-1999 in the suburbs of Chongqing. The results indicated that there were three aphid populations Rhopalosiphum maidis Fitch., Rhopalosiphum padi Linn. and Sitobion avenae Fabricius distributed on the spring sowing maize. The mixed aphid populations traded off during the growth period of spring sowing maize, and two peaks of quantitative counts were shown at the mid and last ten days of May and the last ten days of June. In addition, the niches of aphid population were also discussed from one dimension (i.e., temporal or spatial) to two dimensions (i.e., temporal and spatial). Through the quantitative analysis of niche breadth and niche overlap, the highly temporal differentiation of M. avenae and the highly gathering character of R. maidis were all indicated. R. padi showed an indistinct differentiation, while R. maidi was a dominated population on the spring sowing maize.

Animals↗

PubMed2026

An integrated single-cell and spatial proteotranscriptomics atlas of fibroblast-driven immunoregulation within the human adult oral cavity.

The immunoregulatory architecture of human oral tissues remains poorly defined. We present an integrated single-cell and spatial proteotranscriptomic atlas profiling >250,000 single-cell transcriptomes and >4 million spatially resolved cells across 13 niches. Using our AI-enabled AstroSuite, we defined neighborhoods and interaction modules, revealing peri-epithelial fibroblast-centered hubs enriched in effector cytokines. We harmonized fibroblast subtypes (universal, immune, peri-epithelial, peri-vascular, peri-neural, antigen-presenting cell [APC]-like, stress responsive, and myofibroblasts) with stress-responsive subtypes partitioning between mucosae and glands (type I and II). Spatial multiomics mapped ligand-receptor programs and identified mucosal stress-responsive fibroblasts as putative immunoregulatory hubs. Niche-aware integration of healthy and diseased datasets revealed fibroblast rewiring into inflammatory and reparative niches. Disease neighborhoods exhibited expansion of major histocompatibility complex (MHC)-I+, MHC-II+, and programmed cell death ligand 1 (PD-L1)+ fibroblasts and predicted spatial engagement with T cells at tertiary lymphoid structures. Together, this atlas identifies fibroblasts as central regulators of structural immunity and provides a scalable framework to target stromal-immune interactions across barrier organs.

Journal Article↗

PubMed2006

GIS-based niche modeling for mapping species' habitat.

Ecological "niche modeling" using presence-only locality data and large-scale environmental variables provides a powerful tool for identifying and mapping suitable habitat for species over large spatial extents. We describe a niche modeling approach that identifies a minimum (rather than an optimum) set of basic habitat requirements for a species, based on the assumption that constant environmental relationships in a species' distribution (i.e., variables that maintain a consistent value where the species occurs) are most likely to be associated with limiting factors. Environmental variables that take on a wide range of values where a species occurs are less informative because they do not limit a species' distribution, at least over the range of variation sampled. This approach is operationalized by partitioning Mahalanobis D2 (standardized difference between values of a set of environmental variables for any point and mean values for those same variables calculated from all points at which a species was detected) into independent components. The smallest of these components represents the linear combination of variables with minimum variance; increasingly larger components represent larger variances and are increasingly less limiting. We illustrate this approach using the California Gnatcatcher (Polioptila californica Brewster) and provide SAS code to implement it.

Animals↗

PubMed1991

The niche of Salsuginus thalkeni, a gill parasite of Fundulus zebrinus.

Distribution of a monogenean parasitic helminth Salsuginus thalkeni on the gills of the fish Fundulus zebrinus is described by calculation of mean positions and niche breadths on the linear spatial resource gradients gill filament length, gill arch length and arch number. All distributions are given for parasites in the presence and absence of various combinations of potential competitors, namely the 6 other parasite species that occupy the same host species. Filament niche breadth was narrowest in the absence of potential competitors; breadth on arch was widest in the presence of potential competitors. Breadth on both resources was correlated positively with mean number of parasites per individual. Arch breadth exhibited cyclic seasonal changes, being lowest in early to mid-summer. Mean position exhibited no repeated pattern of variation on either resource. The results are considered consistent with predictions about the niche structures of species in unsaturated noninteractive specialist communities.

Analysis of Variance↗

PubMed2026

Novel immunotherapeutic strategies for colorectal cancer treatment: Advances, challenges, and future directions.

Immunotherapy has reshaped the treatment landscape of colorectal cancer (CRC), with the clearest and most durable benefit established in mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) disease. However, framing CRC immunotherapy simply as "MSI-H responsive versus microsatellite stable (MSS) resistant" is no longer sufficient. Recent studies indicate that a subset of proficient mismatch repair (pMMR) colon cancers, particularly in the neoadjuvant setting, can mount clinically meaningful responses to immune checkpoint blockade, suggesting that disease stage, local immune organization, and treatment timing critically influence immunotherapy sensitivity. In parallel, emerging evidence has expanded the relevant immune landscape beyond the tumor bed itself, showing that spatially organized stromal and adipose niches can actively divert tumor-reactive lymphocytes and promote immune escape. These advances shift the central challenge in CRC immunotherapy from simply identifying new agents to defining when and in whom immune resistance is reversible, and which biological bottlenecks-such as vascular dysfunction, myeloid suppression, and spatial immune exclusion-must be overcome. In this context, alternative checkpoint inhibitors, bispecific antibodies, cellular therapies, vaccines, nanotechnology-enabled platforms, and microbiome-targeted approaches remain important, but their translational maturity and evidentiary support differ substantially. Biomarker development is likewise evolving from static genomic classification toward dynamic and mechanism-informed stratification incorporating circulating tumor DNA (ctDNA), chromosomal instability, immune architecture, and treatment-induced response trajectories. This review synthesizes recent advances in CRC immunotherapy while emphasizing evidence hierarchy, biomarker-guided patient selection, and the mechanistic basis of combination strategies. We argue that the next phase of CRC immunotherapy will depend less on the indiscriminate addition of novel agents and more on the rational deployment of immunotherapy across molecularly, spatially, and temporally defined disease states.

Humans↗

PubMed2001

Towards a cognitive niche: divergent foraging strategies resulting from limited cognitive ability of foraging herbivores in a spatially complex environment.

A model was developed to explain one mechanism whereby differential optimal foraging strategies can occur between species as a result of selection for competition avoidance. This is the primary requirement for niche differentiation to evolve without a difference in the underlying foraging ability or morphology. The model used an individual-based patch choice mechanism, whereby herbivores move from patch to patch seeking food with the highest nutrient intake characteristics. The choice of patch was governed by a parameter, mu, which determined to what extent information in the landscape at different distances from the herbivore was used by it to make foraging decisions. A genetic algorithm was used to optimise the value, mu, in a complex landscape. The value of mu quickly converged to a single value with stabilising selection occurring when there was only a single species foraging. When there was a competing species with a fixed value of mu, the value of mu evolved to be above or below the mean for the single species mean depending on whether the value of mu for the competitor was below, or above the single-species mean, respectively. This was indicative of niche segregation. However mu tended to vary unstably over time when allowed to vary simultaneously in both species, although there was evidence for interaction between the two values. These results indicate that there can be a competitive advantage in choosing a cognitive strategy that is complementary to that used by other species.

Algorithms↗

PubMed2007

Soil nutrients influence spatial distributions of tropical tree species.

The importance of niche vs. neutral assembly mechanisms in structuring tropical tree communities remains an important unsettled question in community ecology [Bell G (2005) Ecology 86:1757-1770]. There is ample evidence that species distributions are determined by soils and habitat factors at landscape (<10(4) km(2)) and regional scales. At local scales (<1 km(2)), however, habitat factors and species distributions show comparable spatial aggregation, making it difficult to disentangle the importance of niche and dispersal processes. In this article, we test soil resource-based niche assembly at a local scale, using species and soil nutrient distributions obtained at high spatial resolution in three diverse neotropical forest plots in Colombia (La Planada), Ecuador (Yasuni), and Panama (Barro Colorado Island). Using spatial distribution maps of >0.5 million individual trees of 1,400 species and 10 essential plant nutrients, we used Monte Carlo simulations of species distributions to test plant-soil associations against null expectations based on dispersal assembly. We found that the spatial distributions of 36-51% of tree species at these sites show strong associations to soil nutrient distributions. Neutral dispersal assembly cannot account for these plant-soil associations or the observed niche breadths of these species. These results indicate that belowground resource availability plays an important role in the assembly of tropical tree communities at local scales and provide the basis for future investigations on the mechanisms of resource competition among tropical tree species.

Ecosystem↗