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Conservación de los Recursos Naturales/legislación & jurisprudencia , Diplomacia , Cooperación Internacional/legislación & jurisprudencia , Vida Silvestre , Aclimatación , Altitud , Animales , Biodiversidad , China , Conservación de los Recursos Naturales/economía , India , Negociación , Plantas , TransportesRESUMEN
Invasive plants are known to alter the soil microbial communities; however, the effects of co-occurring native and invasive congeners on the soil bacterial diversity and their predictive metabolic profiles are not known. Here, we compared the rhizosphere bacterial communities of invasive Prosopis juliflora and its native congener Prosopis cineraria using high-throughput sequencing of the 16S rRNA gene. Unweighted Pair Group Method with Arithmetic mean (UPGMA) based dendrogram revealed significant variation in the communities of these co-occurring Prosopis species. Additionally, Canonical Correspondence Analysis (CCA) based on microbial communities in addition to the soil physiochemical parameters viz. soil pH, electrical conductivity, moisture content and sampling depth showed ~ 80% of the variation in bacterial communities of the rhizosphere and control soil. We observed that Proteobacteria was the predominant phylum of P. juliflora rhizosphere and the control soil, while P. cineraria rhizosphere was dominated by Cyanobacteria. Notably, the invasive P. juliflora rhizosphere showed an enhanced abundance of bacterial phyla like Actinobacteria, Chloroflexi, Firmicutes and Acidobacteria compared to the native P. cineraria as well as the control soil. Predictive metagenomics revealed that the bacterial communities of the P. juliflora rhizosphere had a higher abundance of pathways involved in antimicrobial biosynthesis and degradation, suggesting probable exposure to enemy attack and an active response mechanism to counter it as compared to native P. cineraria. Interestingly, the higher antimicrobial biosynthesis predicted in the invasive rhizosphere microbiome is further corroborated by the fact that the bacterial isolates purified from the rhizosphere of P. juliflora belonged to genera like Streptomyces, Isoptericola and Brevibacterium from the phylum Actinobacteria, which are widely reported for their antibiotic production ability. In conclusion, our results demonstrate that the co-occurring native and invasive Prosopis species have significantly different rhizosphere bacterial communities in terms of composition, diversity and their predictive metabolic potentials. In addition, the rhizosphere microbiome of invasive Prosopis proffers it a fitness advantage and influences invasion success of the species.
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Microbiota , Prosopis , ARN Ribosómico 16S/genética , Rizosfera , Suelo , Microbiología del SueloRESUMEN
A novel strain of Planctomycetes, designated JC670T, was isolated from a high altitude (~ 2900 m above sea level) soil sample collected from Garhwal region in the Western Himalaya. Colonies of this strain were observed to be light pink coloured with spherical to oval shaped cells having crateriform structures distributed all over the cell surface. The cells divide by budding. Strain JC670T was found to grow well at pH 7.0 and pH 8.0 and to tolerate up to 2% NaCl (w/v). MK6 was the only respiratory quinone identified. The major fatty acids of strain JC670T were identified as C18:1ω9c, C18:0 and C16:0, and phosphatidylcholine, two unidentified phospholipids and six unidentified lipids are present as the polar lipids. The polyamines putrescine and sym-homospermidine were detected. Strain JC670T shows high 16S rRNA gene sequence identity (95.4%) with Paludisphaera borealis PX4T. The draft genome size of strain JC670T is 7.97 Mb, with G + C content of 70.4 mol%. Based on phylogenetic analyses with the sequences of ninety-two core genes, low dDDH value (20.6%), low gANI (76.8%) and low AAI (69.1%) results, differential chemotaxonomic and physiological properties, strain JC670T (= KCTC 72850T = NBRC 114339T) is recognised as the type strain of a new species of the genus Paludisphaera, for which we propose the name Paludisphaera soli sp. nov.
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Altitud , Planctomycetales/clasificación , Planctomycetales/aislamiento & purificación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos/análisis , Fosfolípidos/análisis , Filogenia , Planctomycetales/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
Despite decades of research, ecologists continue to debate how spatial patterns of species richness arise across elevational gradients on the Earth. The equivocal results of these studies could emanate from variations in study design, sampling effort and data analysis. In this study, we demonstrate that the richness patterns of 2,781 (2,197 non-endemic and 584 endemic) angiosperm species along an elevational gradient of 300-5,300 m in the Eastern Himalaya are hump-shaped, spatial scale of extent (the proportion of elevational gradient studied) dependent and growth form specific. Endemics peaked at higher elevations than non-endemics across all growth forms (trees, shrubs, climbers, and herbs). Richness patterns were influenced by the proportional representation of the largest physiognomic group (herbs). We show that with increasing spatial scale of extent, the richness patterns change from a monotonic to a hump-shaped pattern and richness maxima shift toward higher elevations across all growth forms. Our investigations revealed that the combination of ambient energy (air temperature, solar radiation, and potential evapo-transpiration) and water availability (soil water content and precipitation) were the main drivers of elevational plant species richness patterns in the Himalaya. This study highlights the importance of factoring in endemism, growth forms, and spatial scale when investigating elevational gradients of plant species distributions and advances our understanding of how macroecological patterns arise.
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Biodiversidad , Fenómenos Fisiológicos de las Plantas , Plantas , Altitud , Ecosistema , Geografía , India , Desarrollo de la Planta , Dispersión de las Plantas , TemperaturaRESUMEN
Conservation efforts globally are skewed toward terrestrial ecosystems. To date, conservation of aquatic ecosystems, in particular fish fauna, is largely neglected. We provide a country-wide assessment of Indian river ecosystems in order to identify and prioritize areas for protection and restoration of freshwater fish fauna. Using various biodiversity and anthropogenic attributes, coupled with tools of ecological modeling, we delineated areas for fish fauna conservation and restoration in the 20 major river basins of India. To do this, we used prioritization analyses and reserve selection algorithms to derive conservation value index (CVI) and vulnerability index (VI) of the river basins. CVI was estimated using endemicity, rarity, conservation value, and taxonomic singularity, while VI was estimated using a disturbance index derived from percent geographic area of the basin under human settlements, human population density, predominant land use, and total number of exotic fish species in each basin. The two indices, CVI and VI, were converted into geo-referenced maps, and each map was super-imposed onto species richness and forest cover maps, respectively. After superimposition, areas with high CVI and low VI shade intensities were delineated for conservation, while areas with high CVI and high VI shade intensities were demarcated for restoration. In view of the importance of freshwater fish for human livelihoods and consumption, and ecosystems of India's rivers, we call for urgent attention to the conservation of their fish fauna along with restoration of their degraded habitats.
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Biodiversidad , Conservación de los Recursos Naturales , Peces/fisiología , Ríos , Animales , Ecosistema , Humanos , India , Densidad de PoblaciónRESUMEN
Understanding how species' traits relate to their status (e.g. invasiveness or rarity) is important because it can help to efficiently focus conservation and management effort and infer mechanisms affecting plant status. This is particularly important for invasiveness, in which proactive action is needed to restrict the establishment of potentially invasive plants. We tested the ability of genome size (DNA 1C-values) to explain invasiveness and compared it with cytogenetic traits (chromosome number and ploidy level). We considered 890 species from 62 genera, from across the angiosperm phylogeny and distributed from tropical to boreal latitudes. We show that invasiveness was negatively related to genome size and positively related to chromosome number (and ploidy level), yet there was a positive relationship between genome size and chromosome number; that is, our result was not caused by collinearity between the traits. Including both traits in explanatory models greatly increased the explanatory power of each. This demonstrates the potential unifying role that genome size, chromosome number and ploidy have as species' traits, despite the diverse impacts they have on plant physiology. It provides support for the continued cataloguing of cytogenetic traits and genome size of the world's flora.
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Cromosomas de las Plantas , Tamaño del Genoma , Genoma de Planta , Especies Introducidas , Ploidias , FilogeniaAsunto(s)
Altitud , Conservación de los Recursos Naturales , Ecología , Ecosistema , Calentamiento Global/prevención & control , Calentamiento Global/estadística & datos numéricos , Conservación de los Recursos Naturales/tendencias , Ecología/tendencias , Actividades Humanas , Humanos , Cubierta de Hielo , India/epidemiología , Lagos , Ríos , Tibet/epidemiologíaRESUMEN
The Himalaya harbors a large number of plant endemics but information on their genome size is largely lacking. This study aims to fulfill this gap by reporting genome sizes for 8 endemic Himalayan plant species (Impatiens devendrae Pusalkar, Impatiens scabrida DC., Impatiens sulcata Wall., Geranium robertianum L., Geranium wallichianum D.Don ex Sweet, Thalictrum cultratum Wall., Thalictrum elegans Wall. ex Royle, Thalictrum foliolosum DC.) from the Western Indian Himalayan state of Uttarakhand. The study involved collecting leaf tissues from each of the 8 plant species, chopping, staining and estimating nuclear DNA content using CyFlow Cube 8 flow cytometer with 532 nm laser light source and an orange-red fluorescence emission (>590 nm). The CyFlow Cube 13 programme was utilised to obtain the median fluorescence value from PI-stained G0/G1 (quiescent phase/first growth phase) nuclei, devoid of cellular debris. The DNA 2C value of each sample was then estimated by comparing the median fluorescence intensity values of both sample and standard (Solanum lycopersicum L.) using the standard scientific formula. The highest DNA 2C-values were observed in Geranium, which ranged from 5.29 ± 0.02 pg to 2.49 ± 0.02 pg. The genome size of Impatiens species varied from 1.49 ± 0.08 pg to 3.14 ± 0.04 pg while the three species of genus Thalictrum had nearly similar genome sizes varying between 1.53 ± 0.01 pg to 1.96 ± 0.06 pg. The coefficient of variation among nuclei varied from 3.52 % to 5.38 % with 103 to 1811 numbers of stained nuclei. The results and framework presented in the current study can serve as a template for future studies that attempt to estimate the genome sizes of endemic plant species in the Himalaya, a global biodiversity epicentre and one of the least studied biodiversity hotspots of the world.
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India is the world's second largest populous nation, fifth largest economy with seventh largest geographical area but experiences high energy poverty. With the lowest per capita energy consumption among world's top ten economies, India ranks at 137 out of 218 nations. Hydropower has the potential to alleviate India's energy asymmetry as well as realize its sustainable growth aspiration of a low-carbon regime. However, hydropower in India has been plagued by debates on human displacement, loss of biodiversity, increased risk of natural disasters, and socio-economic conflicts making it an unpopular energy alternative. Here, we review and address various concerns related to India's hydropower sector, examine scientific evidence, analyze energy policy imperatives, geopolitical considerations, and future directions for a sustainable hydropower policy in India in the context of ongoing climate change. Evidence indicates that besides electricity generation, hydropower infrastructure helps: (i) avert floods, (ii) mitigate the impacts of global warming, and (iii) ensure redistribution of water to arid regions and improve water security. As a part of sustainable hydropower policy, we propose that most of the ecological and social problems associated with hydropower development can be avoided to a great extent through careful planning, proper project design, responsible ownership, and public participation. As short-term measures, we propose: (i) entrepreneurs and planners follow credible and transparent pre-project investigations, (ii) mandatory implementation of environmental management plans, and (iii) better accountability and transparency of statutory bodies as well as hydropower developers. For long-term measures, we suggest: (i) create a 'National Institute of Energy & Environmental Sustainability' to oversee post-project hydropower developmental activities, (ii) streamline various bureaucratic and institutional procedures, and (ii) establish a trans-boundary water management system for seamless and coordinated implementation of hydropower development programs across upstream-downstream nations.
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Indian Himalayan basins are earmarked for widespread dam building, but aggregate effects of these dams on terrestrial ecosystems are unknown. We mapped distribution of 292 dams (under construction and proposed) and projected effects of these dams on terrestrial ecosystems under different scenarios of land-cover loss. We analyzed land-cover data of the Himalayan valleys, where dams are located. We estimated dam density on fifth- through seventh-order rivers and compared these estimates with current global figures. We used a species-area relation model (SAR) to predict short- and long-term species extinctions driven by deforestation. We used scatter plots and correlation studies to analyze distribution patterns of species and dams and to reveal potential overlap between species-rich areas and dam sites. We investigated effects of disturbance on community structure of undisturbed forests. Nearly 90% of Indian Himalayan valleys would be affected by dam building and 27% of these dams would affect dense forests. Our model projected that 54,117 ha of forests would be submerged and 114,361 ha would be damaged by dam-related activities. A dam density of 0.3247/1000 km(2) would be nearly 62 times greater than current average global figures; the average of 1 dam for every 32 km of river channel would be 1.5 times higher than figures reported for U.S. rivers. Our results show that most dams would be located in species-rich areas of the Himalaya. The SAR model projected that by 2025, deforestation due to dam building would likely result in extinction of 22 angiosperm and 7 vertebrate taxa. Disturbance due to dam building would likely reduce tree species richness by 35%, tree density by 42%, and tree basal cover by 30% in dense forests. These results, combined with relatively weak national environmental impact assessment and implementation, point toward significant loss of species if all proposed dams in the Indian Himalaya are constructed.
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Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Movimientos del Agua , Animales , Mariposas Diurnas/fisiología , Sistemas de Información Geográfica , India , Magnoliopsida/fisiología , Vertebrados/fisiologíaRESUMEN
As the two largest countries by population, China and India have pervasive effects on the ecosphere. Because of their human population size and long international boundary, they share biodiversity and the threats to it, as well as crops, pests and diseases. We ranked the two countries on a variety of environmental challenges and solutions, illustrating quantitatively their environmental footprint and the parallels between them regarding the threats to their human populations and biodiversity. Yet we show that China and India continue to have few co-authorships in environmental publications, even as their major funding for scientific research has expanded. An agenda for collaboration between China and India can start with the shared Himalaya, linking the countries' scientists and institutions. A broader agenda can then be framed around environmental challenges that have regional patterns. Coordinated and collaborative research has the potential to improve the two countries' environmental performance, with implications for global sustainability.
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Ciencia Ambiental , Biodiversidad , China , Humanos , IndiaRESUMEN
The Himalaya is one of the youngest and the loftiest mountain chains of the world; it is also referred to as the water tower of Asia. The Himalayan region harbors nearly 10,000 plant species constituting approximately 2.5% of the global angiosperm diversity of which over 4,000 are endemics. The present-day Himalayan flora consists of an admixture of immigrant taxa and diversified species over the last 40 million years. The interesting questions about the Himalayan flora discussed here are: how did the Himalaya achieve high endemic plant diversity starting with immigrant taxa and what were the main drivers of this diversity? This contribution aims to answer these questions and raise some more. We review and analyze existing information from diverse areas of earth and climate sciences, palaeobiology and phytogeography to evolve a bio-chronological record of plant species divergence and evolution in the Himalaya. From the analysis we infer the effects of major environmental upheavals on plant diversity in the region. The understanding developed in the following discussion is based on the idea that Himalaya experienced at least five phases of major geophysical upheavals, namely: (i) mega-collision between India and Eurasian plates, (ii) tectonic uplift in phases and progressive landform elevation, (iii) onset of southwest (SW) Indian monsoon, (iv) spurring of arid conditions in Central Asia, and (v) cyclic phases of cooling and warming in the Quaternary. The geophysical upheavals that were potentially disrupting for the ecosystem stability had a key role in providing impetus for biological diversification. The upheavals produced new geophysical environments, new ecological niches, imposed physical and physiological isolation barriers, acted as natural selection sieves and led to the formation of new species. This contribution aims to develop a comprehensive understanding of the plant biodiversity profile of the Himalaya in the context of complex, interconnected and dynamic relationship between earth system processes, climate and plant diversity.
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Global average temperature increase during the last century has induced species geographic range shifts and extinctions. Montane floras, in particular, are highly sensitive to climate change and mountains serve as suitable observation sites for tracing climate-induced biological response. The Himalaya constitute an important global biodiversity hotspot, yet studies on species' response to climate change from this region are lacking. Here we use historical (1849-50) and the recent (2007-2010) data on temperature and endemic species' elevational ranges to perform a correlative study in the two alpine valleys of Sikkim. We show that the ongoing warming in the alpine Sikkim Himalaya has transformed the plant assemblages. This study lends support to the hypothesis that changing climate is causing species distribution changes. We provide first evidence of warmer winters in the region compared to the last two centuries, with mean temperatures of the warmest and the coldest months may have increased by 0.76±0.25°C and 3.65±2°C, respectively. Warming-driven geographical range shifts were recorded in 87% of 124 endemic plant species studied in the region; upper range extensions of species have resulted in increased species richness in the upper alpine zone, compared to the 19(th) century. We recorded a shift of 23-998 m in species' upper elevation limit and a mean upward displacement rate of 27.53±22.04 m/decade in the present study. We infer that the present-day plant assemblages and community structure in the Himalaya is substantially different from the last century and is, therefore, in a state of flux under the impact of warming. The continued trend of warming is likely to result in ongoing elevational range contractions and eventually, species extinctions, particularly at mountaintops.
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Altitud , Biodiversidad , Clima , Ecosistema , Plantas , Geografía , SikkimRESUMEN
BACKGROUND: Studying diversity and distribution patterns of species along elevational gradients and understanding drivers behind these patterns is central to macroecology and conservation biology. A number of studies on biogeographic gradients are available for terrestrial ecosystems, but freshwater ecosystems remain largely neglected. In particular, we know very little about the species richness gradients and their drivers in the Himalaya, a global biodiversity hotspot. METHODOLOGY/PRINCIPAL FINDINGS: We collated taxonomic and distribution data of fish species from 16 freshwater Himalayan rivers and carried out empirical studies on environmental drivers and fish diversity and distribution in the Teesta river (Eastern Himalaya). We examined patterns of fish species richness along the Himalayan elevational gradients (50-3800 m) and sought to understand the drivers behind the emerging patterns. We used generalized linear models (GLM) and generalized additive models (GAM) to examine the richness patterns; GLM was used to investigate relationship between fish species richness and various environmental variables. Regression modelling involved stepwise procedures, including elimination of collinear variables, best model selection, based on the least Akaike's information criterion (AIC) and the highest percentage of deviance explained (D(2)). This maiden study on the Himalayan fishes revealed that total and non-endemic fish species richness monotonously decrease with increasing elevation, while endemics peaked around mid elevations (700-1500 m). The best explanatory model (synthetic model) indicated that water discharge is the best predictor of fish species richness patterns in the Himalayan rivers. CONCLUSIONS/SIGNIFICANCE: This study, carried out along one of the longest bioclimatic elevation gradients of the world, lends support to Rapoport's elevational rule as opposed to mid domain effect hypothesis. We propose a species-discharge model and contradict species-area model in predicting fish species richness. We suggest that drivers of richness gradients in terrestrial and aquatic ecosystems are likely to be different. These studies are crucial in context of the impacts of unprecedented on-going river regulation on fish diversity and distribution in the Himalaya.