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1.
BMC Plant Biol ; 24(1): 234, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561674

RESUMO

Parthenium hysterophorus L. (Asteraceae) is a highly prevalent invasive species in subtropical regions across the world. It has recently been seen to shift from low (subtropical) to high (sub-temperate) elevations. Nevertheless, there is a dearth of research investigating the adaptive responses and the significance of leaf functional traits in promoting the expansion to high elevations. The current study investigated the variations and trade-offs among 14 leaf traits (structural, photosynthetic, and nutrient content) of P. hysterophorus across different elevations in the western Himalayas, India. Plots measuring 20 × 40 m were established at different elevations (700 m, 1100 m, 1400 m, and 1800 m) to collect leaf trait data for P. hysterophorus. Along the elevational gradient, significant variations were noticed in leaf morphological parameters, leaf nutrient content, and leaf photosynthetic parameters. Significant increases were observed in the specific leaf area, leaf thickness, and chlorophyll a, total chlorophyll and carotenoid content, as well as leaf nitrogen and phosphorus content with elevation. On the other hand, there were reductions in the amount of chlorophyll b, photosynthetic efficiency, leaf dry matter content, leaf mass per area, and leaf water content. The trait-trait relationships between leaf water content and dry weight and between leaf area and dry weight were stronger at higher elevations. The results show that leaf trait variability and trait-trait correlations are very important for sustaining plant fitness and growth rates in low-temperature, high-irradiance, resource-limited environments at relatively high elevations. To summarise, the findings suggest that P. hysterophorus can expand its range to higher elevations by broadening its functional niche through changes in leaf traits and resource utilisation strategies.


Assuntos
Parthenium hysterophorus , Plantas , Clorofila A , Himalaia , Água , Folhas de Planta
2.
Photosynth Res ; 159(1): 29-59, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38270813

RESUMO

Species distributed across a wide elevation range have broad environmental tolerance and adopt specific adaptation strategies to cope with varying climatic conditions. The aim of this study is to understand the patterns of variation in leaf eco-physiological traits that are related to the adaptation of species with a wide distribution in different climatic conditions. We studied the variability in eco-physiological traits of two co-occurring species of Western Himalaya (Rumex nepalensis and Taraxacum officinale), along elevational gradients. We conducted our study in elevations ranging from 1000 to 4000 m a.s.l. in three transects separated in an eco-region spanning 2.5° latitudes and 2.3° longitudes in the Western Himalaya. We hypothesized substantial variation in eco-physiological traits, especially increased net rate of photosynthesis (PN), Rubisco specific activity (RSA), and biochemicals at higher elevations, enabling species to adapt to varying environmental conditions. Therefore, the photosynthetic measurements along with leaf sampling were carried out during the months of June-August and the variations in photosynthetic performance and other leaf traits were assessed. Data was analyzed using a linear mixed effect model with 'species,' 'elevation' as fixed and 'transect' as random factor. Elevation had a significant effect on majority of traits. It was found that PN and maximum carboxylation rate of Rubisco (Vcmax) have unimodal or declining trend along increasing elevations. High RSA was observed at higher elevations in all the three transects. Trends for biochemical traits such as total soluble sugars, total soluble proteins, proline, and total phenolics content suggested an increase in these traits for the survival of plants in harsh environments of higher elevations. Our study reveals that although there is considerable variation in the eco-physiological traits of the two species across elevational gradients of different transects, there are certain similarities in the patterns that depict their high adaptive potential in varying climatic conditions.


Assuntos
Folhas de Planta , Ribulose-Bifosfato Carboxilase , Himalaia , Fenótipo , Folhas de Planta/fisiologia , Plantas
3.
Mol Phylogenet Evol ; 193: 108023, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342159

RESUMO

The Himalaya-Hengduan Mountains (HHM), a renowned biodiversity hotspot of the world, harbors the most extensive habitats for alpine plants with extraordinary high levels of endemism. Although the general evolution pattern has been elucidated, the underlying processes driving spectacular radiations in many species-rich groups remain elusive. Corydalis DC. is widely distributed throughout the Northern Hemisphere containing more than 500 species, with high diversity in HHM and adjacent regions. Using 95 plastid genes, 3,258,640 nuclear single nucleotide polymorphisms (SNPs) and eight single-copy nuclear genes (SCNs) generated from genome skimming data, we reconstructed a robust time-calibrated phylogeny of Corydalis comprising more than 100 species that represented all subgenera and most sections. Molecular dating indicated that all main clades of Corydalis began to diverge in the Eocene, with the majority of extant species in HHM emerged from a diversification burst after the middle Miocene. Global pattern of mean divergence times indicated that species distributed in HHM were considerably younger than those in other regions, particularly for the two most species-rich clades (V and VI) of Corydalis. The early divergence and the recent diversification of Corydalis were most likely promoted by the continuous orogenesis and climate change associated with the uplift of the Qinghai-Tibetan Plateau (QTP). Our study demonstrates the effectivity of phylogenomic analyses with genome skimming data on the phylogeny of species-rich taxa, and sheds lights on how the uplift of QTP has triggered the evolutionary radiations of large plant genera in HHM and adjacent regions.


Assuntos
Corydalis , Filogenia , Himalaia , Biodiversidade , Ecossistema , Plantas
4.
Environ Sci Technol ; 58(1): 459-467, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38152050

RESUMO

Atmospheric phosphorus is a vital nutrient for ecosystems whose sources and fate are still debated in the fragile Himalayan region, hindering our comprehension of its local ecological impact. This study provides novel insights into atmospheric phosphorus based on the study of total suspended particulate matter at the Qomolangma station. Contrary to the prevailing assumptions, we show that biomass burning (BB), not mineral dust, dominates total dissolved phosphorus (TDP, bioavailable) deposition in this arid region, especially during spring. While total phosphorus is mainly derived from dust (77% annually), TDP is largely affected by the transport of regional biomass-burning plumes from South Asia. During BB pollution episodes, TDP causing springtime TDP fluxes alone accounts for 43% of the annual budget. This suggests that BB outweighs dust in supplying bioavailable phosphorus, a critical nutrient, required to sustain Himalayas' ecological functions. Overall, this first-hand field evidence refines the regional and global phosphorus budget by demonstrating that BB emission, while still unrecognized, is a significant source of P, even in the remote mountains of the Himalayas. It also reveals the heterogeneity of atmospheric phosphorus deposition in that region, which will help predict changes in the impacted ecosystems as the deposition patterns vary.


Assuntos
Poluentes Atmosféricos , Biomassa , Poluentes Atmosféricos/análise , Fósforo , Ecossistema , Himalaia , Poeira/análise , Material Particulado/análise , Minerais , Proteínas de Ligação a DNA , Monitoramento Ambiental , Aerossóis/análise
5.
Mol Biol Rep ; 51(1): 75, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38175298

RESUMO

BACKGROUND: Aconitum species, belonging to Ranunculaceae, have high medicinal importance but due to their overexploitation come under IUCN (International Union for Conservation of Nature) red list. The precise identification of the Aconitum species is equally important because they are used in herbal formulations. The present study aimed to develop an efficient DNA barcode system for the authentic identification of Aconitum species. METHODS AND RESULTS: A set of 92 barcode gene sequences (including 12 developed during the present study and 80 retrieved from NCBI) of 5 Aconitum species (A. heterophyllum, A. vialoceum, A. japonicum, A. napellus, and A. stapfianum) were analyzed using three methods (tree-based, distance-based, and similarity-based) for species discrimination. The PWG-distance method was found most effective for species discrimination. The discrimination rate of PWG- distance ranged from 33.3% (rbcL + trnH-psbA) to 100% (ITS, rbcL + ITS, ITS + trnH-psbA and rbcL + ITS + trnH-psbA). Among DNA barcodes and their combinations, the ITS marker had the highest degree of species discrimination (NJ-40%, PWG-100% and BLAST-40%), followed by trnH-psbA (NJ-20%, PWG-60% and BLAST-20%). ITS also had higher barcoding gap as compared to other individual barcodes and their combinations. Further, we also analyzed six Aconitum species (A. balfourii, A. ferox, A. heterophyllum, A. rotundifolium, A. soongaricum and A. violaceum) existing in Western Himalaya. These species were distinguished clearly through tree-based method using the ITS barcode gene with 100% species resolution. CONCLUSION: ITS showed the best species discrimination power and was used to develop species-specific barcodes for Aconitum species. DNA barcodes developed during the present study can be used to identify Aconitum species.


Assuntos
Aconitum , Animais , Aconitum/genética , Código de Barras de DNA Taxonômico , Himalaia , DNA , Espécies em Perigo de Extinção
6.
J Sep Sci ; 47(1): e2300795, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38234031

RESUMO

Swertia species are common ingredients in numerous herbal remedies. It is also used to treat a wide range of illnesses and possess diverse therapeutic activities. The aim of the study is to elucidate the comprehensive metabolomics profile of Swertia chirayita and the role of various extraction methods in the phytochemical compositions of the extracts of S. chirayita, and their antioxidant and enzyme inhibitory activities. Extraction of the stems, leaves, and flowering tops of S. chirayita was performed by maceration, infusion, and soxhlation using methanol and water as solvent. Extracts were subjected to phytochemical profiling by a liquid-chromatographic system. Antioxidant and enzyme inhibitory activity was carried out. The metabolomics profiling showed that a diverse range of specialized metabolites were present in the stems and leaves & flowering tops of the plant. All the extracts showed substantial antioxidant and enzyme inhibitory activities further confirmed by molecular docking studies. This study appraised the use of S. chirayita aerial parts as a potential antioxidant and its therapeutic application in various chronic illnesses including Alzheimer's disease, diabetes, and other skin-related disorders.


Assuntos
Antioxidantes , Swertia , Antioxidantes/farmacologia , Antioxidantes/química , Swertia/química , Extratos Vegetais/química , Himalaia , Simulação de Acoplamento Molecular , Compostos Fitoquímicos
7.
Indian J Med Res ; 159(2): 241-245, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517219

RESUMO

BACKGROUND OBJECTIVES: High-altitude headache (HAH) and headache in acute mountain sickness (AMS) are common among lowlanders ascending to the high altitude and are often confused with one another. A pilot study was undertaken to analyze HAH and AMS cases in Indian lowlanders ascending to Leh city (3500 m) in western Himalayas. METHODS: A total number of 1228 Indian lowlanders, who ascended (fresh and re-inductees) by air and acclimatized, participated in this pilot study. The intensity of headache was assessed by the Visual Analogue Score. The parameters of HAH as per the International Classification of Headache Disorders-3 and 2018 Revised Lake Louise Questionnaire (LLQ) were used to differentiate HAH and AMS. RESULTS: Out of 1228 cases, 78 (6.4%) cases had headache, of which 24 (1.95%) cases were HAH only, 40 (3.25%) cases AMS only and 14 (1.14%) cases were defined as both HAH and AMS. There was a significant difference in heart rate [F (2,51) = (4.756), P =0.01] between these groups. It also showed a difference in the correlation between the parameters within the groups. The Odd's Ratio of AMS in fresh and re-inductees was found to be 4.5 and for HAH it was 4.33. INTERPRETATION CONCLUSIONS: The findings of this study suggest that LLQ has a tendency of overestimating AMS by including HAH cases. Furthermore differential parameters exhibit differences when AMS and HAH are considered separately. Re-inductees showed a lower incidence of HAH and AMS.


Assuntos
Doença da Altitude , Humanos , Doença da Altitude/complicações , Doença da Altitude/diagnóstico , Doença da Altitude/epidemiologia , Altitude , Himalaia , Projetos Piloto , Doença Aguda , Cefaleia/epidemiologia , Cefaleia/etiologia , Inquéritos e Questionários
8.
Chem Biodivers ; 21(2): e202301656, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38217357

RESUMO

Aconitum spp. are important medicinal plants mentioned in Ayurveda as Ativisa or Vatsanabha. The present study aims to evaluate anti-rheumatic potential in seven Aconitum species and correlation with aconitine and hypaconitine content. Anti-rheumatic potential was analyzed through in vitro xanthine oxidase inhibition, anti-inflammatory and ROS scavenging assays; and quantification of aconitine and hypaconitine with RP-HPLC method validated as per ICH guidelines. The findings reveal that A. palmatum possessed the most promising response (IC50 =12.68±0.15 µg/ml) followed by A. ferox (IC50 =12.912±1.87 µg/ml) for xanthin oxidase inhibition. We observed a wide variation in aconitine and hypaconitine content ranging from 0.018 %-1.37 % and 0.0051 %-0.077 % respectively on dry weight basis. Aconitine and hypaconitine showed moderate positive correlation (r=0.68 and 0.59 respectively) with anti-rheumatic potential. The study identifies potential alternative species of Aconitum that can help in sustainable availability of quality raw material.


Assuntos
Aconitina/análogos & derivados , Aconitum , Medicamentos de Ervas Chinesas , Aconitina/farmacologia , Aconitina/análise , Siquim , Himalaia , Cromatografia Líquida de Alta Pressão/métodos , Índia
9.
J Basic Microbiol ; 64(3): e2300461, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38115562

RESUMO

Fungal communities colonizing Ophiocordyceps spp. plays a crucial ecological role in their natural habitat, contributing to infect the host larvae, and influencing their occurrence. Although associated fungi with the newly described Ophiocordyceps indica, from the Indian Western Himalaya remains unclear. Therefore, we untangled the culturable fungal communities associated with O. indica and soil adhered to it, collected from low-height areas of Himachal Pradesh, India. The study resulted in the identification of 111 fungal isolates representing 17 families, with maximum fungal isolates (36.03%) within Cordycipitaceae. Interestingly, a total of 24 genera were found associated with O. indica and adhered soil, of which 12 were common, 8 were exclusive to O. indica and 4 were only limited to soil. Additionally, the influence of soil physicochemical parameters on fungal diversity indices revealed a positive correlation with humidity and available nitrogen and a negative correlation with pH and available phosphorus. These findings provide insights into the culturable fungal diversity of O. indica and the soil adhering to it, thus can contribute to the understanding of host-microbial interactions. Furthermore, these associations can be explored as a source of bioactive metabolites to combat the unending industrial demands.


Assuntos
Hypocreales , Micobioma , Humanos , Himalaia , Ecossistema , Solo , Microbiologia do Solo
10.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396942

RESUMO

Environmental stress at high altitudes drives the development of distinct adaptive mechanisms in plants. However, studies exploring the genetic adaptive mechanisms of high-altitude plant species are scarce. In the present study, we explored the high-altitude adaptive mechanisms of plants in the Himalayas through whole-genome resequencing. We studied two widespread members of the Himalayan endemic alpine genus Roscoea (Zingiberaceae): R. alpina (a selfing species) and R. purpurea (an outcrossing species). These species are distributed widely in the Himalayas with distinct non-overlapping altitude distributions; R. alpina is distributed at higher elevations, and R. purpurea occurs at lower elevations. Compared to R. purpurea, R. alpina exhibited higher levels of linkage disequilibrium, Tajima's D, and inbreeding coefficient, as well as lower recombination rates and genetic diversity. Approximately 96.3% of the genes in the reference genome underwent significant genetic divergence (FST ≥ 0.25). We reported 58 completely divergent genes (FST = 1), of which only 17 genes were annotated with specific functions. The functions of these genes were primarily related to adapting to the specific characteristics of high-altitude environments. Our findings provide novel insights into how evolutionary innovations promote the adaptation of mountain alpine species to high altitudes and harsh habitats.


Assuntos
Altitude , Zingiberaceae , Himalaia , Genômica , Evolução Biológica , Adaptação Fisiológica/genética
11.
J Fish Biol ; 104(2): 497-504, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37278092

RESUMO

A total of 40 specimens of the genus Schizothorax (Cyprinidae: Schizothoracinae), including 10 matured males, 19 matured females and 11 juveniles, were captured from the Kirong Tsangpo River in China, which is located in the southern slope of the Central Himalayas. These specimens are identified as Schizothorax richardsonii (Grey, 1832) based on morphological characters and molecular analyses using mitochondrial Cyt b gene sequences. The Kirong population of S. richardsonii is relatively isolated from other populations in the Himalayas and has low genetic diversity. This is the first record of the genus Schizothorax fish in rivers of the Central Himalayas in China. As S. richardsonii is a vulnerable species on the IUCN Red List, a protection plan should be conducted to reduce the impact of anthropogenic disturbance by monitoring the natural population dynamics and assessing the ecological determinants of its distribution.


Assuntos
Cyprinidae , Rios , Animais , Himalaia , Filogenia , China , Cyprinidae/genética
12.
Environ Monit Assess ; 196(5): 441, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598137

RESUMO

Since treelines are generally fire-free, the trees growing there are expected to have thin bark, unless adaptation to other factors than fire results in the selection of a thick bark. Related to this is also higher proportional investment in inner bark in such an environment of infrequent fire. This study has considered stem bark thickness both in absolute and relative terms and also in the frame of the composition of outer and inner bark components of 20 tree species along an elevation transect (2100-3300 m) in high ranges of the Central Himalaya leading to treelines. The study species varied from 2.1 to 16.2 mm for total bark thickness and from 1.2 to 18.85% for relative bark thickness. The average absolute total bark thickness across the tree species decreased with elevation from forest to treeline, both when trees of all diameters (10.2 ± 0.84 mm for forest and 6.9 ± 1.79 mm for treeline) and those of the same stem diameter range (18-20 m) were compared (9.10 ± 1.30 mm for forest species and 6.38 ± 1.31 mm for treeline species). Nevertheless, the treeline bark thickness was similar to those of several forest communities considered to have comparatively thick bark. Like many other biological structures, bark carries out multiple functions; therefore, its thickness could be affected by more than one environmental factor. We suggest that the requirement of mechanical resistance to the snowfall, rainstorms, wind and adaptation to a high sunlight and UV radiations or storage of water, and non-structural carbohydrates could affect total, outer and inner bark thickness. Studies on these aspects in similar ecosystems may help understand the multi-functional attributes of the bark. For trees of comparable sizes (trees with 18-20 cm diameter at breast height) treeline species also had lower relative bark thickness (< 6%) than trees of forest below it (> 7%). The median proportion of inner bark of the total bark (70.5%) for our 20 species was more than that for savannas (~ 50%), exposed to frequent fire regime and similar to those of in cool sclerophyllous forests and temperate rain forests where fire return time is > 100 years. However, it was lower than the inner bark proportion reported for tropical rain forests. To conclude, in spite of a fire-free environment, the Himalayan treeline and adjoining forest species show mixed bark characters.


Assuntos
Ecossistema , Árvores , Himalaia , Casca de Planta , Monitoramento Ambiental
13.
Environ Monit Assess ; 196(3): 305, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407661

RESUMO

Identifying hydrochemical fingerprints of groundwater is a challenge in areas with complex geological settings. This study takes the Gilgit-Baltistan, a complex geological area in west high Himalayas, Pakistan, as the study area to get insights into the hydrochemcial genesis and quality of groundwater in complex geological mountainous regions. A total of 53 samples were collected across the area to determine the hydrochemical characteristics and formation of groundwater. Results revealed groundwater there is characterized by slightly alkaline and soft fresh feature. Groundwater is dominated by the hydrochemical facies of HCO3·SO4-Ca·Mg type. The factor method yields three components (PCs) of principal component analysis, which together explain 75.71% of the total variances. The positive correlation of EC, TDS, Ca2+, SO42-, K+ in PC1, and NO3-, Cl- in PC2 indicate that a combination of natural and anthropogenic activities influences groundwater hydrochemistry. Water-rock interaction is the main mechanism governing the natural hydrochemistry of groundwater. The negative correlation of Cl-, SO42-, Ca2+, and Na+ with NDVI attributes to inorganic salt uptake by plant roots. Groundwater chemical composition is also affected by the type of land use. Groundwater is characterized as excellent and good water quality based on the entropy-weighted water quality index assessment, and is suitable for drinking purposes except for very few samples, while aqueous fluoride would pose potential health threats to water consumers in western high Himalayas, and infants are most at risk compared to other populations. This study will help to deepen the hydrochemial formation mechanism and exploitation suitability of groundwater resources in the mountainous areas that undergone the combined actions of nature and human activities, and provide insights into the characteristics of water environmental quality in western Himalayas area.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Lactente , Humanos , Himalaia , Transporte Biológico , Efeitos Antropogênicos
14.
Environ Monit Assess ; 196(2): 194, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265534

RESUMO

Interpretation of a fossil pollen data for the vegetation and climate reconstruction of any region needs a modern pollen-vegetation analogue for its calibration. We analyzed the surface sediments and moss polsters for the pollen and microcharcoal records to understand the modern pollen-vegetation relationship and human activities in the Baspa Valley, Kinnaur, Himachal Pradesh. Presently, valley is occupied by the arboreal and non-arboreal vegetation of temperate to subalpine habitats and land use activities. The recovered pollen assemblages showed variability in the dispersal behavior of pollen of taxa growing along the valley transect and also captured the signals of human activities over land use. The overall dominance of arboreal pollen in the recovered pollen assemblage corresponds with the dominant growth of conifers and broadleaf tree taxa and represents the valley vegetation at a regional scale. However, the profuse pollen production of a few arboreal taxa and long distance pollen transport from one vegetation zone to other by the strong upthermic valley winds could bias the pollen representation of in-situ vegetation. The high pollen frequency of non-arboreal taxa in the open meadows represents the near vicinity to their plant source. Human activities like fire burning and cultivation by the local population are evident by the recovery of microcharcoal particles and pollen of plants belonging to Cerealia Poaceae, Asteraceae, Amaranthaceae, Polygonaceae, Rosaceae, Juglandaceae, etc. The dataset taken as modern pollen-vegetation analogue is useful to assess past changes in the vegetation and land cover in relation to climate and human factors for future sustenance.


Assuntos
Meio Ambiente , Monitoramento Ambiental , Humanos , Himalaia , Pólen , Clima
15.
Environ Monit Assess ; 196(3): 241, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38324063

RESUMO

Phytochemicals are broadly acknowledged for their health-promoting effects owing to the fact of their capacity to counteract free radicals (e.g., superoxide anion radical, hydroxyl radical, hydroperoxyl radical, singlet oxygen, hypochlorite, and nitric oxide) and shield against oxidative stress induced by environmental factors. This study aimed to investigate the relationship between altitude, morphology, soil parameters, in vitro antioxidant potential and phytochemical composition of Phlomis cashmeriana collected from four different locations of Kashmir Himalaya characterized by diverse habitats and elevations. Various factors, such as extraction method, solvent polarity, and habitat conditions, can impact the quantity and efficacy of phytochemicals in plants. The aim of current study was to analyze phytochemical composition and antioxidant activity of P. cashmeriana, an important medicinal plant found in the Kashmir Himalaya region. The antioxidant activity was accessed using several assays and the plant populations were selected based on their diverse habitat features and altitudes. HR-LCMS was conducted for both below-ground and above-ground parts. Some important compounds such as, catechin, vinainsenoside, acutilobin, and kaempferol were reported for the first time from P. cashmeriana. Results showed that methanol was the most efficient solvent for extracting phytochemicals. During the current study, it was also found that the below-ground parts exhibited superior antioxidant activity compared to the above-ground parts. Notably, Site IV demonstrated the highest antioxidant potential; a positive correlation between altitude and antioxidant activity was also found. In conclusion, present research identified specific elite populations having highest antioxidant potential and are well-suited for large-scale cultivation of P. cashmeriana.


Assuntos
Antioxidantes , Phlomis , Himalaia , Monitoramento Ambiental , Compostos Fitoquímicos , Solventes
16.
Environ Monit Assess ; 196(5): 469, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656433

RESUMO

The potential of soil organic carbon fractions for agroforestry systems (AFSs) is not well understood. Five distinct AFSs were tested for its impact on soil organic carbon fractionation, carbon index, and microbial activity in North Eastern Himalayas, India. The mean labile carbon (LC) ranged from 4.55 to 5.43 kg soil-1 across the land use systems. Napier system observed the lowest very labile carbon (VLC) 12.36 kg soil-1 in 60-75-cm depth. The mean non labile carbon (NLC) ranged from 15.67 to 16.83 g kg soil-1 across the land use. Highest less labile carbon (LLC) was observed in agri-horti-silviculture (AHS) followed by agri-silvi-horticulture (ASH) land use system. The black gram + mandarin + Alnus nepalensis land use recorded higher lability index (1.66) followed by maize + Schima wallichii (1.65) in 0-15-cm depth. Among the different land use systems, carbon pool index increased in all the depths over buckwheat + mandarin. The mean carbon management index (CMI) value ranged from 167.02 to 210.12 among the land use system. The mean CMI was highest in black gram + mandarin + Alnus nepalensis (210.12) followed by soybean + Ficus hookerii + guava (191.56), maize + Schima wallichii (281.71), and lowest in buckwheat + mandarin (167.02). Among the AFSs, black gram + mandarin + Alnus nepalensis showed greater amount of carbon pool index, lability index, and carbon management index and, hence, considered the best sustainable agroforestry system to sequester more carbon in the Sikkim Himalaya. Such system also retained more different organic carbon fractions. The mean CMI value ranged from 167.02 to 210.12 among AFSs. Acid phosphatase activity was more during the rainy season followed by winter and summer season. Similar trends were followed by the urease activity in all the three seasons. Overall conclusion from this investigation is that SOC fractions, carbon index, and microbial activity levels are strongly influenced by the prevailing agroforestry systems.


Assuntos
Agricultura , Carbono , Monitoramento Ambiental , Microbiologia do Solo , Solo , Índia , Carbono/análise , Solo/química , Agricultura Florestal , Himalaia
17.
Environ Monit Assess ; 196(10): 928, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39266934

RESUMO

Sediment loss and export pose significant global environmental issues, profoundly affecting water quality, soil fertility, and ecosystem stability, particularly in vulnerable mountain ecosystems like the Indian Himalayas. The present study used remote sensing data and the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) sediment delivery ratio (SDR) model to analyze spatial-temporal variations in soil loss (SL), sediment export (SE), and sediment retention (SR) capabilities in the South Shimla watershed, Himachal Pradesh, India, from 1993 to 2023. The findings showed significant changes in land use and land cover (LULC): evergreen forest and scrub land decreased sharply by 11.53% and 36.43%, respectively, while agricultural areas and built-up areas increased notably by 71.16% and 215.76%, respectively. Despite a decline of 19.18% in SL and 24.43% in SE, sediment loss and export varied across the study area, highlighting the heterogeneous nature of sediment dynamics. The overall retention capacity increased by 2.59%, with scrub forests playing a critical role in SR, while built-up areas showed the lowest retention. Northern and central sub-watersheds (SWs) experienced a significant decrease in retention capacity (from - 1.92 to - 11.6%), whereas those in the southern and eastern regions saw an increase in SR (from 3.69 to 28.24%). These results underscore the complex interactions between LULC changes, sediment dynamics, and retention services, highlighting the importance of preserving natural ecosystems and informing policy for landscape-based conservation and development planning in the vulnerable Himalayan region.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Índia , Sedimentos Geológicos/química , Solo/química , Agricultura , Florestas , Himalaia
18.
Environ Monit Assess ; 196(10): 925, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264478

RESUMO

This is the first report on high pesticide tolerance displayed by the microbiota isolated from the sediments of two high-altitude lakes, located in the Singalila National Park, Singalila Ridge of the Himalayas. Given the remote location of these lakes, direct exposure to chemical pesticides is highly unlikely. However, the high tolerance to commonly used pesticides exhibited, i.e. up to 250 mg/ml, suggests repeated exposure and contamination of the lakes. Microbial growth in the presence of varying concentrations of the pesticides, namely, emamectin benzoate, thiamethoxam, quinalphos, deltamethrin, spiromesifen, flubendiamide, monocrotophos, fipronil, fenazaquin and phorate, was tested. Results showed resistance to all pesticides except fenazaquin and fipronil, up to 250 mg/ml. For the latter two, tolerance was displayed up to a concentration of 40 mg/ml. Tolerance may potentially result from the transport and deposition of pesticides from nearby locations, particularly the tea plantations of Darjeeling and Eastern Nepal. This may create great ecological risks as these lakes are an important water source for endemic wildlife of this protected area. They also hold great significance to the religious sentiment of the local tribes who worship these lakes as sacred. The study highlights the need for monitoring pesticide contamination in such pristine high-altitude environments and the mechanisms of long-range pollutant transport.


Assuntos
Altitude , Monitoramento Ambiental , Lagos , Praguicidas , Poluentes Químicos da Água , Lagos/microbiologia , Lagos/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Nepal , Nitrilas/toxicidade , Microbiota/efeitos dos fármacos , Piretrinas , Himalaia , Ivermectina/análogos & derivados
19.
Zoo Biol ; 43(2): 183-187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38234126

RESUMO

The ability of females to store sperm for extended periods in their reproductive tracts (termed long-term sperm storage, LTSS) has been reported across a diversity of vertebrate taxa. The evolutionary, ecological, and physiological significance of LTSS is wide-ranging and includes the ability to produce offspring when mates may be temporally scarce by way of decoupling copulation from ovulation, inbreeding avoidance, and the generation and maintenance of genetic diversity in progeny. Among vertebrate lineages, nonavian reptiles exhibit a remarkable capacity for LTSS, with the production of viable offspring reported after periods exceeding 6 years since prior contact with a potential mate. Given that female reptiles are able to store viable sperm for prolonged periods, it is important to disentangle LTSS from that of facultative parthenogenesis (FP), a reproductive trait which appears widespread among all reptile lineages. The implications of this distinction are particularly important in the context of the development and management of captive breeding programs. To accurately determine between the two reproductive strategies, genomic screening is highly recommended. Following a period of isolation for 13 months from a potential male mate, a female Himalayan Mountain Pitviper (Ovophis monticola) produced a clutch of three male offspring. Here, through genome-scale analyses of the female and her progeny, we document the first record of LTSS in this genus and exclude FP as the alternative hypothesis.


Assuntos
Animais de Zoológico , Sêmen , Masculino , Animais , Feminino , Himalaia , Reprodução/fisiologia , Espermatozoides
20.
Waste Manag Res ; 42(10): 901-910, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39069718

RESUMO

Non-governmental organizations (NGOs) play a critical role in addressing solid waste management (SWM) challenges in remote mountain communities, including the ecologically fragile Himalayan region. This study evaluates the impact of Healing Himalayas, an NGO, in Rakchham village, Himachal Pradesh, India. The objectives were to evaluate the effectiveness of Healing Himalayas' decentralized SWM model in promoting stakeholder engagement and resource recovery, assess the role of collaborations between local authorities and the NGO in financing waste management practices, investigate the influence of tourism and seasonal variations on solid waste generation patterns and waste management practices in Rakchham, and material recovery facilities, followed by glass (36.7%), paper/cardboard (18.4%) and metal (4.1%). A fee-based system involving the local village council funded waste operations. Waste generation exhibited significant seasonal fluctuations, with tourism influxes driving increased volumes. Healing Himalayas' initiatives promoted community participation, with over 15 awareness workshops conducted. Key challenges included limited financial resources, inadequate infrastructure, lack of advanced treatment facilities and need for context-specific solutions like efficient wet waste management in cold climates. The study highlights Healing Himalayas' decentralized model's success in fostering stakeholder engagement, behavioural change and resource recovery. The findings inform effective strategies for NGO-led waste management initiatives tailored to remote Himalayan communities.


Assuntos
Resíduos Sólidos , Gerenciamento de Resíduos , Índia , Resíduos Sólidos/análise , Gerenciamento de Resíduos/métodos , Organizações , Eliminação de Resíduos/métodos , Himalaia
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