Introduction

Climate change has pushed around one million animal and plant species to the brink of extinction, with many facing this threat within the next few decades. Since 1900, the average abundance of native species in most major terrestrial habitats has declined by at least 20%. The number of invasive alien species per country has surged by approximately 70% since 1970. Additionally, more than 500,000 terrestrial species, representing roughly 9% of the world’s estimated 5.9 million species, lack sufficient habitat for long-term survival without restoration efforts1. Of the over 300,000 known plant species, 40% assessed by the IUCN are at risk of extinction2.

Among the ecosystems affected by climate change, the mountain ecosystems of the Himalaya are considered highly vulnerable3. The Himalaya is experiencing a warming rate three times higher (0.06 °C/year) than the global average, exposing it to significantly higher temperatures4. Recent reports have noted the greatest warming rate of 0.3–0.5 °C per decade in Northwestern Himalaya5. Rapid warming poses the greatest threat to the survival of high elevation, narrow niche species by limiting the space available for colonization. The challenge is further compounded by the region’s complex biogeography6. Therefore, understanding the population distribution and predicting the habitat suitability of these endangered high elevation, narrow niche species under changing climate conditions is essential for developing effective conservation strategies7,8.

Aconitum heterophyllum Wall. ex Royle, locally known as Atis, Patis, Patish, or Patrees is a rare, endangered, endemic, terrestrial medicinal herb, widely used and distributed across the sub-alpine to alpine open slopes at elevations ranging from 2400 to 4500 m asl9,10,11. The genus, belonging to the Ranunculaceae family, comprises over 250 species, most of which are popularly known as the “Queen of all poisons”12. A. heterophyllum grows well in moist soil and shady habitats. However, its slow growth rate and low seed germination exacerbate the effects of climate change.

Aconitum heterophyllum is renowned for its diverse bioactive compounds, including alkaloids such as heterophyllisine, heterophylline, heterophyllidine, atisine, isoatisine, hetidine, hetsinone, and benzoylheteratisine13. Additionally, the species contains saponins and flavonoids, contributing to its therapeutic properties14. Distinguished as the only non-toxic member of the genus, A. heterophyllum is noted for its extensive pharmacological properties, including hepatoprotective, analgesic, diuretic, antipyretic, astringent, aphrodisiac, antioxidant, alexipharmic, anodyne, anti-atrabilious, anti-flatulent, anti-periodic, carminative, antibacterial, antifungal, insecticidal, antiviral, anticancer, anti-inflammatory, brine shrimp cytotoxic, and immune-stimulant activities15,16,17,18.

The secondary metabolites of this species are used to treat ailments related to the immune, digestive, and nervous systems, playing a crucial role in traditional medicine systems in India, China, Nepal, and Bhutan14,19. Its tuberous roots are traditionally used to treat various conditions, including dyspepsia, abdominal pain, diabetes, diarrhea, gastric disorders, worm infestations, cirrhosis, respiratory tract infections, fever, vomiting, skin disorders, anemia, joint disorders, hysteria, throat and urinary infections, inflammation, cough, toothache, general debility, reproductive disorders, and as a substitute for quinine20,21,22.

In Ayurveda, A. heterophyllum is a key component in formulations such as Balachaturbhadra Churna, Sudarshana Churna, Panchatiktaka, Guggulu, Ghrta, and Rasnerandadi Kwatha. As a result, the current market price of this herb in India is extremely high, over 204 USD. The species is at high risk due to overexploitation in the Himalayan region.

Climate change has had a considerable impact on the population and distribution of Aconitum heterophyllum. As a narrow-niche species, it is predicted to experience a significant reduction in suitable habitats due to climate change and anthropogenic pressures22,23,24. Over the past 100 years, the species has exhibited significantly earlier flowering by 17–25 days (P < 0.01)25. Increased temperature has led to earlier flowering, occurring 26 days earlier for every 1000 m elevation25. These shifts in flowering times indicate environmental disruptions, which could negatively impact the species’ survival and reproduction. Therefore, assessing suitable habitats for A. heterophullum is crucial.

While sveral studies have highlighted the impact of climate change on the distribution and medicinal value of species like A. heterophyllum26,27, Trillium govanianum28,29, and others within the Indian Himalayan Region (IHR), most assessments of climate change impact on A. heterophyllum have been conducted at larger scales, such as in the western Himalaya, or regionally in Kashmir Himalaya. There is a critical gap in understanding the species’ specific distribution and habitat suitability in Himachal Pradesh. Furthermore, the ecological and phenological responses of this species to climate change, including its current and projected population status, have not been comprehensively examined at a region-specific level.

This study provides a pioneering, focused assessment of A. heterophyllum’s population dynamics and habitat suitability within Himachal Pradesh. By utilizing a combination of Species Distribution Modeling (SDM) based on the MaxEnt algorithm and climate change projections (SSPs 126, 245, and 585), this study not only evaluates the current habitat suitability but also models the potential future distribution under various climate scenarios, providing valuable insights into how climate change will shape its future survival. The integration of bioclimatic variables, phenology, and ecological dynamics unique to Himachal Pradesh makes this study novel and relevant for conservation strategies tailored to this region.

The current study aims to: (a) Conduct an ecological assessment of Aconitum heterophyllum in its natural habitat to understand its current distribution and ecological dynamics, (b) Evaluate how suitable habitats for A. heterophyllum may change under present and future climate scenarios using the MaxEnt modeling approach, and (c) Identify and prioritize suitable habitats for targeted conservation efforts.

By addressing these objectives, the research seeks to fill a critical gap in knowledge regarding the impact of climate change on this endangered species and provide valuable insights for developing restoration strategies in the region.

The findings of this study will provide a robust foundation for prioritizing key conservation areas and adaptive management strategies that can mitigate the impacts of climate change on A. heterophyllum, ensuring the protection and sustainable use of this important medicinal species in the face of global environmental changes. Relevant institutional, national, and international guidelines and legislation were complied during this study. No plant part(s) or seeds were collected from the field. Permission from Himachal Pradesh state forest department was obtained for field study.

Material and methods

Study area

This study was undertaken in the alpine region (locally known as Thatch or meadows) of Himachal Pradesh above 3000 m. The state is located in the northwestern parts of the Indian Himalayan Region, the area stretches from 30° 22′ N to 33° 12′ N latitude and 75° 45′ E to 79° 04′ E longitude (Fig. 1). It covers an area of 55,673 km2 and approximately 10.43% of the total of the Indian Himalayan Region. The elevational range of Himachal Pradesh varies from 300 to 7000 m asl. The average temperature in the state varies from 28 to 32 °C (82–90 °F). Most of the state lies at the foothills of Dhauladhar range. The soils of Himachal Pradesh are grouped into alluvial soils, Brown hill soils, Brown earth, Brown Forest soils, Grey wooded or Podzolic soils, grey, brown podzolic soils, Panasonic soils, Humus and iron Podzols and Alpine humus mountain skeletal soils. The climate varies from hot and sub-humid tropical (450–900 m) in the southern low tracts, warm and temperate (900–1800 m), cool and temperate (1900–2400 m), and cold glacial and alpine (2400–4800 m) in the northern and eastern high elevated mountain ranges. The vegetation varies from dry scrub forests at lower elevations to alpine pastures at higher elevations. Major forest types found in Himachal Pradesh are mixed deciduous forests, such as bamboo, chir pine, oak, deodar, kail, fir, and spruce forests. In Himachal Pradesh, 15.90% of total forest cover is dominated by sub-alpine forests and alpine pastures30. Himachal Pradesh covers 51,589.34 km2 of high-elevation area, with sub alpine (2800–3200 m) area at 2407.91 km2 and above 3200 m area at 24,133.81 km2, accounting for 51.44% of the total high-elevation area.

Fig. 1
figure 1

Study area map showing the elevational distribution in Himachal Pradesh. ArcMap 10.8 (https://unikassel-its.maps.arcgis.com/home/).

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Species description

Morphology and phenology for identification

Aconitum heterophyllum is an erect, and tuberous herb of 15–20 cm in height31. The vegetative development starts in May, while flowering and fruiting occur between August and October in the second or third year of growth. Flowers are white-violet32, with amplexicaulis, heteromorphic, spirally arranged dark green leaves with long petioles and tubers are whitish-grey in color with tapering ends33 (Fig. 2).

Fig. 2
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Aconitum heterophyllum in alpine habitats of Himachal Pradesh.

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Distribution and nativity

The species is distributed in grassy meadows and upper oak/coniferous forests34. It can also be found in glacial rivers, rocky, damp places, alpine dry scrub, open grass, alpine slopes, shady moist alpine slopes, and forest borders. It is commonly found in Carex nubigena-Kobresia duthiei habitats. This species is found in the Rhododendron Forest and the Quercus-Abies Forest borders35.

Aconitum heterophyllum is native to India, Nepal, and Pakistan. In the Indian Himalayan Region, the species is restricted to the northwestern Himalayan states of Jammu and Kashmir, Himachal Pradesh, and Uttarakhand, as well as Sikkim and Arunachal Pradesh in the east36,37 (Table 1). Thirty-three species of Aconitum can be found in the Great Himalayas, extending from Afghanistan in the west to Myanmar (Burma) in the east27. These are also found in Europe and Asia, where they are used as indigenous and traditional medicine because of their alkaloid content (aconite)22.

Table 1 Distribution of Aconitum heterophyllum across the Hindu Kush Himalaya.
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Population assessment

Population assessment of A. heterophyllum in the alpine region was conducted from 2018 to 2024 during the peak flowering season in Himachal Pradesh. Populations of A. heterophyllum were found in 06 meadows, and the population was estimated using a stratified random sampling method along the elevational gradient. 1 \(\times\) 1 m quadrats were used for estimating the population of herbs across major habitat types. Twenty plots were laid at each site where the Number of individuals of A. heterophyllum were counted from each occurrence site and standard ecological methods were followed for population estimation53 (Fig. 3).

Fig. 3
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Design of sampling plot for population assessment of Aconitum heterophyllum.

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Species data

Data on species occurrence was primarily collected through extensive research conducted in Himachal Pradesh. Species occurrence points from published literature, online herbariums, national herbarium records, and the Global Biodiversity Information Facility54 were collected. To prevent autocorrelation and enhance the credibility of data, the occurrence points were gathered, verified for redundancy, and processed using Google Earth Pro (version 7.3.6.9796) and ArcGIS. Any occurrence points that were superfluous or unreasonable were eliminated. Using R55 (version 4.2.2), spatial thinning along 5 × 5 km grid cells was carried out using the Sp thin package on Wallace (v2.0.5)56,57. A 5 km spatial thinning was applied to ensure spatial independence of sample points, accounting for ecological variation and dispersal patterns of Aconitum heterophyllum in the rugged terrain of Himachal Pradesh. This distance prevents spatial autocorrelation and maintains adequate representation of habitat conditions. Spatial thinning reduced the number of A. heterophyllum occurrences to 47 from a total of 59 occurences. These rarefied locations were used to create species distribution models (SDMs).

Climatic data and other environmental variables

The climate data were downloaded from WorldClim database version 2.1 (https://www.worldclim.org/). 19 Bioclimatic variables derived from monthly temperature and precipitation data and one topographic variable (elevation) from Shuttle Radar Topographic Data (SRTM) at a spatial resolution of 30 arc-second were downloaded58. ArcGIS was used to extract aspect and slope information from the SRTM elevation data. Global land cover data at 300 m resolution was obtained and analyzed in R using the ‘geodata’ package. Soil cover data was obtained from the Harmonized World Soil Database (HWSD) on the Food and Agricultural Organization of the United Nations (FAO) soil portal (https://www.fao.org/soils-portal/data-hub/soil-maps-and-databases/harmonized-world-soil-database-v12/en/). Land cover and soil cover data were resampled to 30 arc-second spatial resolution for bioclimatic variables using the R package ‘raster’. To eliminate multicollinearity, Pearson’s correlation coefficient for variable pairs was determined with the R package ‘VIF’. Variables with strong multicollinearity (> 0.7) were deleted to improve model predictability. SDMs were generated using ten variables: Mean Diurnal Range (Bio2), Isothermality (Bio2/Bio7) (× 100), Mean Temperature of Wettest Quarter (Bio8), Precipitation Seasonality (Coefficient of Variation) (Bio15), Precipitation of Coldest Quarter (Bio19), elevation (meters above sea level), slope, aspect, soil cover, and land cover. Topographic variables (elevation, slope, and aspect) were treated as static; hence the same topographic layers were used for current and future datasets.

Model design and species distribution modelling

The expected change in species distribution was estimated using the Global Climate Model (GCMs), Hadley Global Environment Model 2-Earth System, (HadGEM3-GC31-LL), under three Shared Socioeconomic Pathways (SSPs); SSP1: (Sustainability—Taking the green road); SSP2 (Middle of the road) and SSP 3 (Regional rivalry—A rocky road) climatic conditions through periods of 2041–2060, and 2061–2080. SSP1 assumes that the emphasis on equity and the de-emphasis of economic growth as an end in high-income countries drives industrialized countries to support developing countries in their development goals. SSP2 illustrates a moderate development tendency, with the world, on average, facing moderate mitigation and adaptation problems but with significant heterogeneity among and within countries. While SSP3 illustrates increasing resource use intensity and fossil fuel dependency, the difficulty of gaining international collaboration and the slow pace of technical progress imply significant hurdles to mitigation. Limited progress in human development, slow income growth, and a lack of functional institutions, particularly those that can act across regions, imply substantial hurdles to adaptation for many populations in all regions59. The model used for future projections are derived from Coupled Model Intercomparison Project 6 (CMIP6) statistically downscaled and calibrated future climate projections. The CMIP 6 model simulate weather at ~ 111 km spatial resolution which is downscaled and interpolated to ~ 1 km spatial resolution for the GCMs using monthly mean values for minimum temperature, maximum temperature, and precipitation60. The selection of the HadGEM3-GC31-LL model was based on its improved spatial resolution (~ 111 km, downscaled to ~ 1 km) and its proven ability to simulate key climatic variables such as temperature and precipitation in complex terrains like the Indian Himalayan Region. This model has been validated in similar studies for the region, demonstrating accuracy in simulating monsoon patterns and temperature gradients, critical factors for Aconitum heterophyllum habitat. Additionally, the HadGEM3-GC31-LL model is part of the CMIP6 ensemble, providing future climate projections under multiple Shared Socioeconomic Pathways (SSPs), which allowed for a comprehensive evaluation of potential climate scenarios affecting the species63. In the MaxEnt model (version 3.4.4 k), land cover and soil cover were incorporated as categorical variables, with each class represented by a distinct integer value corresponding to specific categories. These raster layers were formatted accordingly and specified as categorical within MaxEnt’s environmental settings, ensuring appropriate interpretation by the algorithm without imposing ordinal relationships. MaxEnt version 3.4.4 k natively supports such categorical predictors in its logistic regression framework. The algorithm is particularly well-suited for species with limited or sparse occurrence data, making it ideal for modeling the distribution of A. heterophyllum64,65. MaxEnt algorithm uses presence only data and is suitable for rare species with restricted distribution or niches64,66,67. With ten replicates, the model was trained at the tenth percentile. In the replicated model, cross-validation techniques were applied, with samples separated into replicate folds and each fold used for test data. The maximum number of background points were 10,000. To reduce model overfitting and overprediction, the regularization multiplier was set to one, with a maximum iteration of 500. 75% of the data was used for model training and 25% for model testing. Model performance and accuracy were evaluated using receiver operator characteristic (ROC) area under the curve (AUC) scores, which range from 0 to 1, with 1 indicating a perfect model. The model with the highest AUC value was considered the best performer68,69. The relative value of each predictor was assessed using the jackknife test’s percentage contribution64. The models were run for the year 2050 (2041–2060) and 2070 (2061–2080).

Results and discussion

Research findings at the global and regional level

Research on A. heterophyllum encompasses a range of topics including phytochemical screening14,70,71, pharmacological evaluations22,70, traditional usage72, conservation initiatives18, and toxicological assessments73. In India, research has concentrated on identifying and quantifying bioactive chemicals, particularly diterpene alkaloids, using advanced techniques such as UHPLC-DAD-QTOF/IMS39,74,75. Pharmacological studies have corroborated its traditional ayurvedic uses, emphasizing its analgesic, anti-inflammatory, antipyretic, antibacterial, anthelmintic, antitussive, and antidiarrheal effects43. Conservation efforts have included micropropagation, in vitro seed germination, genetic uniformity validation, and habitat modelling to assess climate change impacts76,77,78. International research, particularly in China and Nepal, has explored traditional medicinal uses, phytochemical properties, and methods for reducing root toxicity, highlighting the plant’s significance in Traditional Chinese Medicine50,51. Given its extensive medicinal uses and significant role in traditional practices, A. heterophyllum has become increasingly important and relevant for conservation efforts. The conservation of this species is crucial not only for preserving its ecological and medicinal value but also for maintaining the traditional practices and benefits it provides across different cultures.

Additionally, Aconitum heterophyllum faces severe threats and its commercially available products (raw tubers, tablets, powder and oil) are available under the trade name, “Ativisha” and the cost of these products range from Rs.360 for 10 tablets to upto Rs.2000 for 100 g tubers/powders/oil. In India, increased commercial demand of more than 200 metric tons and market value of approx. 7500 rs/Kg in the pharmaceutical industry has resulted in overexploitation, habitat degradation, and loss of natural populations in the wild49,79,80. The decreasing population size has also resulted in illegal collection and marketing. During the collection, the whole plant is uprooted for tuber harvesting contributing to the decreasing availability in the natural habitats. In the Himalaya, the natural population of the species is not sufficient to meet the increasing market demand22. The species’ erratic distribution, poor density, low seedling survival and regeneration capabilities, slow growth, high medicinal values, and anthropogenic pressure may eventually lead to extinction without an efficient conservation action program81. The high likelihood that A. heterophyllum will become extinct in the near future as a result of recent, current, and future threats emphasizes the importance of assessing the population of A. heterophyllum in the Himalayas, as well as identifying its current and future habitat suitability and environmental variables influencing its distribution.

Distribution, population structure and habitat preference of Aconitum heterophyllum

In Himachal Pradesh, A. heterophyllum was found in six habitats ranging from 3000 to 3700 m. The species was identified with the help of expert consultation (Dr. K. Chandrasekar, Plant taxonomist) and also with the help of type specimens of the species available in the herbarium facility of G.B. Pant National Institute of Himalayan Environment, Almora, Uttarakhand, India. No voucher specimens were collected from the field due to the endangered status of the species in Himachal Pradesh and as per the regulations of Himachal Pradesh Forest Department. Within the designated habitats, individual counts (n) for A. heterophyllum varied from 1 to 16 in occurrence sites, with frequencies and abundance ranging from 5 to 25 (%) and 1–15, respectively (Table 2). The habitat assessment for A. heterophyllum in several occurrence points revealed associations with a total of 91 species of trees, shurbs and herbs from 71 genera and 35 families. The species was found in habitats dominated by tree species such as Abies pindrow, Betula utilis and Pinus wallichiana at lower elevations. Berberis glaucocarpa, Rhododendron anthopogon, Rhododendron campanulatum, and Rhododendron lepidotum were the most common shrubs found in A. heterophyllum habitat. Among herbs, species such as Bistorta affinis, Fragaria nubicola, Trifolium repens, and Anemonastrum polyanthes were major associates (Table 3). Of the total associated species, dominant taxa were herbs representing (84%), shrubs (10%), trees (2%) and ferns (2%). Among the dominant group of plant families associated with A. heterophyllum, Asteraceae was the dominant herb family, followed by Rosaceae and Polygonaceae. Similarly, the dominant tree family was represented by Pinaceae. The associated dominant shrub families were Ericaceae and Rosaceae.

Table 2 Site characteristics of the selected populations of Aconitum heterophyllum.
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Table 3 Phytosociological attributes of Aconitum heterophyllum in different location.
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Significant variables under the current scenario

The jackknife test for A. heterophyllum indicates that elevation is the most significant variable, contributing 28.2%, followed by Bio15; Precipitation seasonality, contributing 16.6% to habitat suitability. Bio8; Mean Temperature of Wettest Quarter contributing 16.04%, Bio19; Precipitation of Coldest Quarter contributing 15.12%, Bio2; Mean Diurnal Range contributing 14.32% to habitat suitability. Slope is the least important variable, contributing 0.04% to the habitat suitability (Fig. 4).

Fig. 4
figure 4

Result of jackknife test for evaluating the relative contribution of the predictor environmental variables to the habitat model of Aconitum heterophyllum.

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Species response to environmental variables

The species response curve to different variables used for modelling reveals the relationship between environmental variables and suitable habitat. Based on the acquired species response curves of single variables, Suitability remains relatively stable (~ 0.75) across most aspect values. This suggests that Aconitum heterophyllum can grow on a wide range of slopes, with no strong preference for a specific direction. The habitat remains suitable across many orientations, indicating adaptability to various microclimates. A slight decline occurs between 200° and 300° (southwest-facing slopes). This means that southwest-facing slopes are slightly less favorable for the species compared to other orientations. Warmer and drier conditions (southwest-facing slopes receive more afternoon sunlight) and higher evaporation rates, reducing moisture availability. A sharp increase is observed at ~ 320° (northwest-facing slopes). Northwest-facing slopes provide better habitat conditions, leading to a sudden increase in suitability. These slopes may retain more moisture and have moderate temperatures, creating a favorable environment. Suitability drastically drops at ~ 360° (north-facing slopes). North-facing slopes receive the least sunlight. This may lead to colder, more shaded environments, which could be less optimal for Aconitum heterophyllum’s growth. Soil conditions or frost accumulation on north-facing slopes might further reduce suitability. High suitability (~ 1.0) for low diurnal temperature ranges (~ 7 to 8 °C) is indicated by Bio2. A sharp decline in suitability as temperature variation increases beyond 9 °C. Habitat Suitability gradually increases with rising isothermality and peaks at ~ 35% isothermality (Bio3) and remains stable. Species response to Bio8 shows high suitability (~ 1.0) for temperatures below 10 °C. A steep decline as temperatures exceed 10–15 °C, reaching near zero at 30 °C. It indicates A. heterophyllum prefers cooler, moist conditions in the wettest season. High temperatures during the wettest quarter are detrimental, possibly leading to heat stress or increased evapotranspiration.This response aligns with the species’ occurrence in high-altitude regions where monsoon temperatures remain low.The species prefered moderate Precipitation seasonality (Bio15) upto 40 mm. The response curve of Bio19; Precipitation of Coldest Quarter indicates that the species can thrive in areas with substantial winter precipitation.The response curve for elevation indicated that the species remains relatively stable upto ~ 3500 to 4000 m and declines steeply at higher elevations. The response cirve for slope indicates that the species thrives in relatively flat or mildly sloped areas. Increasing slope negatively impacts habitat suitability (Fig. 5).

Fig. 5
figure 5

Response curves for environmental predictors (A) Bio2; mean diurnal range, (B) Bio3; isothermality, (C) Bio8; mean temperature of wettest quarter, (D) Bio15; precipitation seasonality, (E) Bio19; precipitation of coldest quarter, (F) elevation, (G) slope, (H) landcover, (I) soil cover (J) Aspect in the species distribution model for Aconitum heterophyllum.

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Current and future predictions of A. heterophyllum

The AUC value of the current model is 0.874 for A. heterophyllum indicating that the environmental variables used in the model effectively explain the distribution of A. heterophyllum. The AUC value for the current model was above 0.5, indicating good model performance. It confirms that the model is better than random guessing at distinguishing between presence and absence (or pseudo-absence) locations of the species. The steeper curve suggests that the model has high sensitivity (ability to correctly predict presence locations) and low false positive rates (Fig. 6). The model maintains a balance between sensitivity and specificity—it does not overpredict or underpredict suitable habitats excessively. The low omission rate at lower thresholds suggests that most true presences are captured, making it a robust prediction model (Fig. 7).

Fig. 6
figure 6

Receiver operating characteristic curve with area under curve (AUC).

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Fig. 7
figure 7

Model representing the omitted and predicted area.

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The current potential habitat for A. heterophyllum is shown in Fig. 8. Dark blue areas represent areas with values less than the 10-percentile training presence, i.e., unsuitable areas for A. heterophyllum. In the current scenario, a suitable potential habitat for A. heterophyllum is in Dhauladhar ranges, Killar Pass of Chamba, alpine regions of Great Himalayan National Park and a few sites in Khoksar and Spiti valleys. Under the current climate, the habitat suitability model delineated and exhibited the predominance of the highest suitability in the alpine and sub-alpine regions of Himachal Pradesh. The species distribution probability increased with elevation up to 3300 m with steep slopes. Of the total current suitable habitat, only 29.66% was of medium habitat suitability. Similarly, only 21.13% of the total current suitable habitat is of high habitat suitability (Table 4).

Fig. 8
figure 8

Current habitat suitability of A. heterophyllum. Maxent 3.4.3 (https://biodiversityinformatics.amnh.org/open_source/maxent/); ArcMap 10.8 (https://unikassel-its.maps.arcgis.com/home/).

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Table 4 Predicted suitable areas (km2) under both current and future climatic conditions.
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Contrary to the current climate conditions, habitat suitability for A. heterophyllum decreased for all SSPs. Under SSP 126, signifying moderate development and environmental degradation, the suitable habitat decreased to 51.28% in 2070. Under SSP 245, signifying moderate development and environmental degradation, the suitable habitat decreased to 53.64% in 2070. In contrast, SSP 585, often associated with high-emission development and challenges to mitigation, the suitable habitat decreased to 54.61% in 2070 from the current suitable habitats. Contrary to SSP 585, total habitat suitability increased from 2050 to 2070 for SSPs 126 and 245. Overall, the species will undergo decline in habitat suitability in future climate scenarios. The probable distribution of suitable habitats in the future is shown in Table 4 (Fig. 9).

Fig. 9
figure 9

Future habitat suitability of A. heterophyllum based on future climate conditions; Blue region indicates no habitat suitability, green indicates poor habitat suitability, red indicates fair habitat suitability, purple indicates good habitat suitability. Maxent 3.4.3 (https://biodiversityinformatics.amnh.org/open_source/maxent/); ArcMap 10.8 (https://unikassel-its.maps.arcgis.com/home/).

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Discussion

The phytosociological analyses using primary data revealed that the maximum density of A. heterophyllum was recorded in the tree community of Abies pindrow at 3306 m asl in Parvati valley of Kullu district, making it the most suitable site. At this site, the low density was accompanied by a high frequency, which indicates its dispersal abilities contradicted by curative significance and soaring market value, unsustainable harvesting of whole plant for its tubers coupled with other factors such as reproductive constraints and climate change, etc.82,83. The restricted occurrence associated with a tree community (Abies pindrow and Betula utilis) might indicate its upward shifting in near future. Other dominant species associated with A. heterophyllum were Potentilla fulgens, Fragaria vesca, Poa alpina, Carex nivalis, Taraxacum officinale, Bergenia stracheyi, Potentilla astrosanguinea, Persicaria nepalensis, Rhodiola quadrifolia, Carex nubigena and Polygonum paronychioides. The marginalized distribution of species depicted localized distribution, prolonged seed dormancy, high seedling mortality and poor regeneration in natural habitats, with opportunities to include local communities in its conservation and management38,47,84.

While the MaxEnt modeling indicates likely shifts in habitat suitability, the projected habitat loss under future climate scenarios poses significant threats to both the species and the local communities who depend on it. The MaxEnt Species Distribution Modelling mapped the distribution of A. heterophyllum under current and future climate conditions. A. heterophyllum is considered an indicator species because of its susceptibility to small climatic changes18. The current study found that elevation and precipitation seasonality are the most important variables determining the current distribution of A. heterophyllum in Himachal Pradesh. The results are consistent with earlier research indicating the distribution of A. heterophyllum in high elevation environments with cooler temperatures and precipitation25. Change in precipitation patterns is directly linked to changes in the physiological and ecological response of the species at various scales such as ecosystem functional traits and species diversity that eventually influences biodiversity1,85,86,87,88. The findings suggest that elevation and precipitation seasonality must be considered while conserving A. heterophyllum wild populations.

Also, the species preferred northwest facing slopes, shady moist habitat conditions at the recorded sites. The species shows moderate adaptability but has a preference for northwest-facing slopes, possibly due to favorable microclimatic conditions (moisture retention and moderate temperature). Southwest and north-facing slopes are less suitable, likely due to excess heat stress (SW) or excessive shade and cold stress (N). Additionally, gentle slopes (< 20°) are ideal, but habitat suitability declines as slopes become steeper. Understanding this pattern helps in identifying potential conservation sites and predicting how climate change may shift the species’ distribution based on aspect and slope related microclimatic changes. Other preferred habitat types were grasslands, meadows, and alpine ecosystems. Thus, along with the target species, the study identified habitat types, plant community types and non-target species that coexist with A. heterophyllum, emphasizing that conservation management and restoration efforts should include both target and non-target species in the identified habitat types. The identified suitable areas in Dhauladhar ranges, alpine regions of Pin valley National Park, the Great Himalayan National Park of Himachal Pradesh, Inderkilla National Park, and Killar ranges should develop a targeted conservation plan for A. hetereophyllum and other associated alpine species in the preferred habitats.

The species’ response to environmental variables indicated that narrow width species such as Aconitum heterophyllum, support a certain elevation range (~ upto 3500–4000 masl) and stable temperature conditions with minimal daily fluctuations. High temperature variability (> 9 °C) reduces suitability, possibly due to increased stress on the plant. This suggests A. heterophyllum is adapted to moderate, stable thermal environments found at mid to high altitudes. A. heterophyllum prefers areas where diurnal temperature fluctuations are consistent with annual trends, suggesting climatic stability. High suitability at ~ 35% isothermality indicates moderate climate stability is ideal for its growth. Extremely low isothermality (< 28%) is unsuitable, likely due to extreme seasonal or diurnal variations with moderate precipitation seasonality upto 40 mm89. This suggests that the species prefers relatively stable precipitation patterns rather than extreme seasonal variations. Dad and Rashid45 and Chandra et al.90 reported similar results for A. heterophyllum, Fritillaria cirrhosa, Meconopsis aculeata, Rheum webbianum and Picrorhiza kurrooa in Kashmir Himalaya and Kumaun Himalaya. The species probability presence also increased with an increase in isothermality constant, indicating that the species favors constant temperature ranges across elevations. High species probability presence during extremely low temperature ranges depicted by Mean Diurnal Range (Bio 2) from 7 to 8 °C and Mean Temperature of Wettest Quarter (Bio 8) from − 17 to – 5 °C indicates the species’ high survival ability in harsh winter conditions with moderate precipitation. The species is highly dependent on specific soil types and shows increasing preference as soil properties change. The species likely requires stable terrain with favorable soil conditions, avoiding steep and unstable areas It indicates species preference for high elevational ranges and certain specific ecological conditions, promoting phenotypic plasticity and enhancing its adaptive capacity91. Given that A. heterophyllum is narrow width species, changing climate conditions may affect the species’ adaptive capacity at present and in the near future.

The projected habitat loss of Aconitum heterophyllum under future climate scenarios poses significant threats to its long-term survival, particularly given its already fragmented and restricted distribution. Ecological management strategies must incorporate these findings by focusing on habitat preservation, restoration, and climate adaptation. One approach could involve the establishment of climate-resilient corridors that link fragmented habitats, facilitating species migration and improving genetic diversity. These corridors should be located within the identified suitable areas in Dhauladhar ranges, alpine regions of Pin valley National Park, the Great Himalayan National Park of Himachal Pradesh, Inderkilla National Park, and Killar ranges. In addition, local communities can be engaged in sustainable harvesting practices, such as the promotion of non-destructive methods for A. heterophyllum’s tubers to prevent overexploitation. High-altitude medicinal plant gardens, focusing on both A. heterophyllum and associated species, could also provide a refuge for the species, contributing to in-situ conservation. Furthermore, the inclusion of adaptive management frameworks in conservation strategies will be essential in addressing both climatic and socio-economic challenges, ensuring long-term ecological resilience. As a high-altitude medicinal plant of substantial ethnopharmacological value, its decline not only represents a loss of biodiversity but also a cultural and economic setback for indigenous and local communities in the western Himalayas who rely on it for traditional medicine and livelihood support. Regions such as Parvati Valley, the Great Himalayan National Park (GHNP), and the Killar Ranges, currently harboring suitable habitats,may witness critical contractions, challenging the resilience of both the species and dependent communities. The decline of A. heterophyllum could erode local knowledge systems passed down through generations, impacting not only the availability of medicinal plants but also the cultural practices tied to their use in healing rituals. If conservation strategies fail to address these dual threats, there is a risk of local extirpation and erosion of traditional knowledge systems. Therefore, region-specific, community-based conservation initiatives such as high-altitude medicinal plant gardens and sustainable harvesting protocols must be integrated into climate adaptation and biodiversity strategies to secure both ecological and socio-cultural resilience.

Aconitum heterophyllum is a late-flowering high-altitude species, typically blooming between September and October. This phenological pattern aligns with the post-monsoon period in the western Himalayas, when cooler temperatures and high soil moisture levels prevail, reaffirming the species’ ecological affinity for moist and cold conditions during the wettest season. Model response curves of key bioclimatic variables—Bio2 (Mean Diurnal Range), Bio3 (Isothermality), and Bio8 (Mean Temperature of Wettest Quarter), indicated that the probability of A. heterophyllum occurrence increases with elevation, peaking around 3300 m. This is consistent with the species’ known altitudinal range and ecological preference for subalpine zones. Climate projections suggest a potential upward shift in the species’ suitable range due to warming trends. Predictions have already been made about the probable shift in suitable habitats of medicinal plants. However, it may increase under certain climatic conditions as depicted by future climate scenarios. The increase in low suitable habitats might be due to zero inclusion of non-biotic interactions in the model. The critical limitation of the model lies in the exclusion of biotic interactions. In natural ecosystems, plant distributions are shaped not only by climatic envelopes but also by complex ecological dynamics. For A. heterophyllum, interspecific competition (e.g., with more thermophilic or invasive species encroaching on higher elevations), herbivory (particularly by ungulates or insect larvae), and pollination networks (involving specific pollinator taxa whose distributions may not shift synchronously with the plant) can all significantly influence its realized niche. The absence of these interactions in correlative models may lead to overestimation of habitat suitability, especially in newly projected zones. To address this, future modeling efforts should incorporate mechanistic or hybrid approaches that embed biotic filters such as dispersal constraints, pollinator availability, or herbivory pressure into species distribution frameworks. This could involve integrating field-derived species interaction data, co-occurrence modeling, or agent-based simulations that represent population dynamics under multiple interacting forces. Such approaches would enhance the ecological realism of projections and inform conservation strategies more effectively.

However, the overall decrease in habitats is an increasing threat of extinction for A. heterophyllum in Himachal Pradesh. Interestingly, projections under the high-emission scenario SSP585 show an increase in marginally suitable habitats, in contrast to moderate scenarios (SSP126 and SSP245). This may reflect the species’ potential plasticity under highly variable and extreme precipitation patterns, as well as longer growing seasons facilitated by elevated temperatures. Furthermore, increased atmospheric CO2 concentrations could enhance photosynthetic efficiency, potentially benefiting alpine herbaceous species in nutrient-limited environments92. The species may benefit from specific local conditions such as microclimate refugia, and reduced competition. However, while this species might thrive upto 2050, the broader impacts of SSP585, including significant global warming and ecosystem shifts, underscore the need for climate mitigation efforts to protect overall biodiversity and ecosystem stability.

While the present study has illuminated the challenges and complexities facing A. heterophyllum, it also underscores the urgent need for integrated conservation strategies that account for both ecological and socio-economic dimensions. The conservation of this medicinal species is vital, not only for biodiversity but also for the cultural and economic resilience of Himalayan communities. Given the complexities of species-environment interactions and the limitations of current models, future research should focus on incorporating biotic interactions and longitudinal field studies to better predict species responses in a rapidly changing climate. For A. heterophyllum, data availability is limited due to its restricted and fragmented distribution, making it susceptible to sampling bias. Additionally, SDMs often assume that the species–climate relationships observed in the present will remain constant in the future, an assumption that may not hold under rapidly changing or novel climatic conditions. Extrapolation into non-analog climates, particularly under high-emission scenarios such as SSP585—can lead to overconfident or ecologically implausible suitability estimates, especially when the model encounters climate combinations not observed in the training dataset. While key environmental predictors such as elevation, precipitation, temperature, slope, aspect, and soil type were incorporated to improve realism, other dynamic factors such as disturbance regimes, land-use changes, and fine-scale microclimatic variability remain unaccounted for. The MaxEnt algorithm, though widely used and robust, may also underrepresent complex nonlinear responses or synergistic interactions among predictors. While the AUC metric was used to evaluate the model’s performance, we acknowledge the lack of empirical validation. Future research should focus on field-based data collection to empirically validate the model’s predictions, assessing its accuracy in real-world scenarios and refining conservation strategies.Therefore, while the present findings provide a strong basis for conservation planning, they should be interpreted with caution and complemented by future efforts that incorporate ensemble modeling, mechanistic data, and longitudinal field validation to better constrain uncertainties and improve ecological forecasting under climate change.

Furthermore, the phytosociological assessment and distribution of Aconitum heterophyllum significantly contributes to SDG 13 (Climate Action) and SDG 15 (Life on Land) by enhancing the understanding of habitat suitability under changing climate conditions. This research aligns with the objectives of the Kunming-Montreal Global Biodiversity Framework (KMGBF) by supporting the conservation of critical ecosystems, contributing to the global goal of protecting 30% of land and marine areas by 2030. In addition, it strengthens global and national conservation policies, such as the Convention on Biological Diversity (CBD) and India’s National Biodiversity Act of 2002, by promoting sustainable harvesting practices and actively involving local communities in conservation efforts. By identifying climate impacts and suitable habitats for Aconitum heterophyllum, this study aids in the development of focused conservation plans and adaptation strategies. These efforts are in direct alignment with the KMGBF’s emphasis on halting biodiversity loss and addressing the intersection of biodiversity conservation and climate resilience, ultimately supporting both national and international biodiversity conservation and climate action goals.

Conclusion

Despite these extensive studies, significant research gaps exist. Comprehensive toxicological profiles and standardized detoxification processes are required to ensure safe medical use. There is a scarcity of comprehensive pharmacokinetics and pharmacodynamics studies, genetic diversity research, established quality control techniques, and rigorous clinical trials to validate conventional claims. Integrative and multidisciplinary techniques that combine ethnobotany, phytochemistry, pharmacology, and conservation biology are critical for generating comprehensive conservation strategies. Also, studies on public awareness and the development of regulatory frameworks are critical to preventing overexploitation and ensuring the long-term usage of Aconitum heterophyllum.

The present study is the first attempt to assemble all information such as morphology, phenology, distribution, phytochemicals, therapeutic properties, traditional uses and modeling the distribution of A. heterophyllum in Himachal Pradesh. This study concludes that MaxEnt modelling can provide information on prospective habitats for endangered species such as Aconitum heterophyllum, favoring moderate temperature stability, cool, moist conditions, and southwest- to northwest-facing slopes. However, it is difficult to find the primary location of threatened species with restricted distribution. Warming trends may increase BIO8 values, reducing suitable habitat, and deforestation and land-use changes may further impact populations. Future conservation strategies should focus on preserving cool, stable microclimates at mid- to high-altitude areas.

In the current climatic conditions, A. heterophyllum shows a suitable region for conservation in the northwestern, southeast and central parts of Himachal Pradesh, including Dhauladhar ranges, alpine regions of Pin valley National Park, and the Great Himalayan National Park. Thus, these regions can be identified as suitable Medicinal Plant Conservation Areas (MPCAs), including ex-situ and in-situ conservation. According to the study, elevation and precipitation are the factors that influence the distribution of A. heterophyllum the most. The species will lose 45–48% of its current habitat by 2070. It illustrates the importance of including more environmental parameters such as soil temperature, evapotranspiration and vegetation types for modelling and ground truthing surveys, as the individual species count was low in the examined locations. In addition to climate change, the species is threatened by habitat destruction through road constructions in the alpine habitats and increasing anthropogenic pressure through tourism, over-harvesting for medicinal purposes, livestock grazing, and to meet the ever-increasing market demand. A lack of information exists on the population status of A. heterophyllum in the northeast and Trans Himalayan region of IHR. Thus, the study will also help in exploring natural populations in the identified suitable habitats. This emphasizes the need for species-specific conservation methods in identified suitable environments.

Additionally, the development of comprehensive toxicological profiles, standardized detoxification processes, and detailed studies on pharmacokinetics, pharmacodynamics, genetic diversity, and quality control methods are essential for validating the species’ medicinal potential. To address these challenges, a multidisciplinary approach that integrates ethnobotany, phytochemistry, pharmacology, conservation biology, and ecological studies is necessary. This will enable the formulation of robust conservation strategies and sustainable harvesting practices. Innovative propagation techniques, such as tissue culture, hydroponics, and aeroponics, can play a vital role in cultivating new plants, thereby reducing pressure on wild populations and ensuring a consistent supply for pharmaceutical purposes. Rigorous clinical trials are essential to validate the therapeutic efficacy of Aconitum heterophyllum, both in its natural populations and in those cultivated through laboratory propagation. The findings of this study will help conservation agenices such as Forest Department, Biodiversity Boards, Medicinal Plant Boards, Research Organizations, and others for developing conservation strategy for protection of this valuable threatened medicinal plant.