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Floristic composition, diversity, dominance and distribution pattern of species and tree population structure were studied in three stands of a sub-tropical wet hill broad-leaved forest of Meghalaya, India, along a disturbance gradient. Tree species diversity declined with increasing disturbance. Disturbed stands showed low equitability or high dominance and the undisturbed stand exhibited high equitability or low dominance. Contagious distribution among the tree species increased with increasing intensity of disturbance. Species showing regular distribution were restricted only to the undisturbed stand. Effect of disturbance on tree population structure was analysed using density-diameter curves. In the disturbed stands tree species showed reverse J-shaped and/or negative exponential curves, while those in the undisturbed stand exhibited sigmoid to bimodal mound shaped curves.

The tribal communities of Meghalaya in northeast India—Khasis, Garos, and Jaintias—have a tradition of environmental conservation based on various religious beliefs which have been passed on from one generation to the other. Based on these beliefs, certain patches of forests are designated as sacred groves under customary law and are protected from any product extraction by the community. Such forests are very rich in biological diversity and harbor many endangered plant species including rare herbs and medicinal plants. Seventy‐nine sacred groves were located, denoted on a geographical map of Meghalaya, and studied for their biodiversity value, status, and vegetation characteristics. A baseline floristic survey revealed that at least 514 species representing 340 genera and 131 families were present in these sacred groves. The status of sacred groves was ascertained through canopy cover estimate. A little over 1.3% of total sacred grove area was undisturbed, 42.1% had relatively dense forest, 26.3% had sparse canopy cover, and 30.3% had open forest. The vegetation characteristics and species diversity of an undisturbed sacred grove were compared with that of an unprotected disturbed forest. The species diversity indices were higher for the sacred grove than for the disturbed forest. The species composition and community characteristics differed significantly between the two forests. Sociocultural aspects of sacred grove conservation were analyzed, and views of the local people were enlisted. Based on the findings, conservation strategies for sacred groves were suggested.

Lists of species underpin many fields of human endeavour, but there are currently no universally accepted principles for deciding which biological species should be accepted when there are alternative taxonomic treatments (and, by extension, which scientific names should be applied to those species). As improvements in information technology make it easier to communicate, access, and aggregate biodiversity information, there is a need for a framework that helps taxonomists and the users of taxonomy decide which taxa and names should be used by society whilst continuing to encourage taxonomic research that leads to new species discoveries, new knowledge of species relationships, and the refinement of existing species concepts. Here, we present 10 principles that can underpin such a governance framework, namely (i) the species list must be based on science and free from nontaxonomic considerations and interference, (ii) governance of the species list must aim for community support and use, (iii) all decisions about list composition must be transparent, (iv) the governance of validated lists of species is separate from the governance of the names of taxa, (v) governance of lists of accepted species must not constrain academic freedom, (vi) the set of criteria considered sufficient to recognise species boundaries may appropriately vary between different taxonomic groups but should be consistent when possible, (vii) a global list must balance conflicting needs for currency and stability by having archived versions, (viii) contributors need appropriate recognition, (ix) list content should be traceable, and (x) a global listing process needs both to encompass global diversity and to accommodate local knowledge of that diversity. We conclude by outlining issues that must be resolved if such a system of taxonomic list governance and a unified list of accepted scientific names generated are to be universally adopted.

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Applied Ecology. Summary 1. The subtropical humid forest of Meghalaya, India, has been exposed to various kinds of cultural disturbance of varying magnitude during recent years. In order to analyse the effect of disturbance on natural regeneration of a few dominant and commercially important tree species, viz. Schima khasiana and the oaks Lithocarpus dealbatus and Quercus griffithii, a study on seed production, dispersal and germination was carried out in three stands, differing in degree of disturbance, during the years 1988-91. 2. Seed production in L. dealbatus and S. khasiana varied significantly between the three stands and increased with increasing disturbance. It increased with increase in d.b.h. of the trees in all three species. Heavy seeding occurred in different years in different species. 3. Lithocarpus and Quercus spp. produced heavier seeds in the disturbed stands than in the undisturbed stand. 4. The number of seeds dispersed from the trees decreased with distance from the parent tree. The dispersal distance for Lithocarpus and Quercus was greater in the disturbed stands than in the undisturbed stand. However, the dispersal distance in the forest was very low irrespective of degree of disturbance. 5. Seed predation decreased and germination increased with distance from the parent tree in all three stands, suggesting that distance-related seed predation was not influenced by disturbance. 6. In an experiment with four treatments the greatest germination of seeds was observed on the moss layer, irrespective of species and forest stand. The presence of litter inhibited germination of seeds to a great extent in all the species. Germination of Lithocarpus and Quercus was better in the undisturbed stand than in the disturbed stands, while that of Schima khasiana was better in the disturbed stands.7. An analysis of the fate of seed populations of the oak species revealed that loss of seeds caused through consumption by rodents and insects and transportation by various agents accounted for more than 98 % of the seeds, while fewer than 1% of them germinated. 8. The findings of the study are discussed in relation to their potential application in management of the disturbed subtropical forests.

Identification of invasion hotspots that support multiple invasive alien species (IAS) is a pre-requisite for control and management of invasion. However, till recently it remained a methodological challenge to precisely determine such invasive hotspots. We identified the hotspots of alien species invasion in India through Ecological Niche Modelling (ENM) using species occurrence data from the Global Biodiversity Information Facility (GBIF). The predicted area of invasion for selected species were classified into 4 categories based on number of model agreements for a region i.e. high, medium, low and very low. About 49% of the total geographical area of India was predicted to be prone to invasion at moderate to high levels of climatic suitability. The intersection of anthropogenic biomes and ecoregions with the regions of 'high' climatic suitability was classified as hotspot of alien plant invasion. Nineteen of 47 ecoregions of India, harboured such hotspots. Most ecologically sensitive regions of India, including the 'biodiversity hotspots' and coastal regions coincide with invasion hotspots, indicating their vulnerability to alien plant invasion. Besides demonstrating the usefulness of ENM and open source data for IAS management, the present study provides a knowledge base for guiding the formulation of an effective policy and management strategy for controlling the invasive alien species.

Nodules of Chamaecrista pumila growing in several locations in India were sampled for anatomical studies and for characterization of their rhizobial microsymbionts. Regardless of their region of origin, the nodules were indeterminate with their bacteroids contained within symbiosomes which were surrounded by pectin. More than 150 strains were isolated from alkaline soils from the Thar Desert (Rajasthan), wet-acidic soils of Shillong (Meghalaya), and from trap experiments using soils from four other states with different agro-ecological regions. Molecular phylogenetic analysis based on five housekeeping (rrs, recA, glnII, dnaK andatpD) and two symbiotic (nodA and nifH) genes was performed for selected strains. Chamaecrista pumila was shown to be nodulated by niche-specific diverse strains of either Ensifer or Bradyrhizobium in alkaline (Thar Desert) to neutral (Tamil Nadu) soils and only Bradyrhizobium strains in acidic (Shillong) soils. Concatenated core gene phylogenies showed four novel Ensifer-MLSA types and nine Bradyrhizobium-MLSA types. Genetically diverse Ensifer strains harbored similar sym genes which were novel. In contrast, significant symbiotic diversity was observed in the Bradyrhizobium strains. The C. pumila strains cross-nodulated Vigna radiata and some wild papilionoid and mimosoid legumes. It is suggested that soil pH and moisture level played important roles in structuring the C. pumila microsymbiont community.

The continuous use of silver nanoparticles (AgNPs) induces drug-resistance in pathogenic bacteria, resulting in the recurrence of biofilms, making them difficult to eradicate. AgNPs in higher concentrations are also toxic to cells. Therefore, an approach that can modulate bacterial quorum sensing (QS) signaling–NP interactions, thereby reducing the production of bacterial pathogenicity traits and minimizing the dose of NPs to suppress bacterial adhesion and colonization, is upmost welcomed. The present work follows an approach where AgNPs are decorated with endolichenic fungus-derived anti-QS chrysophanol (CP-AgNPs) that increases chrysophanol bacterial QS signaling interactions. The advantage of this approach lies in enhancing and long-term preventing bacterial adhesion and subsequent colonization of urinary catheters (UCs) mediated by CP-AgNPs through the inhibition of QS signaling as compared to that with citrate-capped AgNPs (Cc-AgNPs) alone. The anti-adhesion and anti-biofouling effects of CP-AgNPs-coated UC surfaces were assessed for the growth of Pseudomonas aeruginosa PAO1 and Escherichia coli under both static and flow conditions. The CP-AgNPs-coated latex and silicone surfaces showed greater than 9-fold anti-adhesion and anti-biofouling effects than the Cc-AgNPs-coated UCs, which shows the practical applicability of this strategy. These effects of CP-AgNPs influenced the surface hydrophobicity, eDNA content, lipopolysaccharide (LPS) production, and virulence gene expression of bacterial biofilm cells, which reduced biofilm invasion and formation. The CP-AgNPs-coated UCs did not induce toxicity in human bladder fibroblast cells, indicating massive biocompatibility. Eventually, the CP-AgNPs system was successfully applied to prevent bacterial biofilm formation in vivo. Thus, the CP-AgNPs reveal their strong use as anti-adhesion and anti-biofouling coating materials, demonstrating their great potential to prevent UC-associated urinary tract infections.