A floristic survey across three coniferous forests of Kashmir Himalaya, India – a checklist

: This study presents a checklist of the flora of three coniferous forests of the Himalayan biodiversity hotspot in Kashmir: low-level blue pine (BP), mixed coniferous (MC) and subalpine (SA) forests. The list includes altitudinal distribution and conservation status of 272 vascular plant species representing 196 genera and 64 families. Excluding neophytes (70 taxa, 62 genera, and 27 families), Magnoliophyta comprised 190 taxa, 139 genera, and 50 families; Pinophyta seven taxa, six genera, and three families; and Pteridophyta three taxa, three genera, and two families. Most speciose families from Magnoliophyta include Compositae, Apiaceae, and Rosaceae. Genera such as Artemisia , Potentilla , Viola , and Saussurea contributed the maximum number of species. In case of Pinophyta, the principal families are Pinaceae with four taxa followed by Cupressaceae (2 taxa), whereas genus Juniperus comprised two species. In Pteridophyta, Pteridaceae (2 taxa) formed the most speciose family. The herbs contributed 177 taxa, followed by tress (15 taxa), shrubs (8) and subshrubs (2). The maximum number of taxa belongs to SA (136 taxa) followed by MC (134 taxa) and BP (83 taxa) forests. The species distribution reveals 20, 30, and 46 taxa are exclusive to BP, MC, and SA forests. More than 16% of taxa are categorized in the International Union for Conservation of Nature (IUCN) Red List, and 24 taxa are endemic to the Himalayan landscape. The checklist provides a roadmap for research, protection and conservation of plant diversity, especially the threatened taxa.


INTRODUCTION
Research on biodiversity became an essential aspect of biological research immediately after the Convention on Biological Diversity (CBD), with the goal of determining the implications of rapid depletion, management and climate change on species composition and diversity. Biodiversity-related data provide a foundation for species conservation and habitat protection (Cadotte 2006). With only 2.2% of global land area, India houses over 18,000 plant species, including 5,000 endemic flora, and is recognized among the 17 global mega-biodiverse countries (Nayar 1996;Singh et al. 2015). About half of the biodiversity hotspots representing 25% of the known biota are reported from mountain ecosystems (Wester et al. 2019). However, until recently, mountains acquired the attention of researchers, policy-makers, and conservationists.
Currently, diverse habitats supporting distinct flora are experiencing the threat of destruction due to fragmentation, rapid human population growth and climate change (Janssen et al. 2016;IUCN 2017). Consistent reductions in plant diversity call for continuous exploration of the population status of flora using systematic (IUCN) criteria, as this is acknowledged as the most rigorous strategy/technique for evaluating the global status of biodiversity and categorizing plants based on their projected risk of extinction (Maes et al. 2015;Orsenigo et al. 2018;Nowak et al. 2020).
The Himalaya, extending from Afghanistan to Myanmar, is one of 36 biodiversity hotspots harbouring a diverse range of flora and fauna, resulting from the phytogeographical complexity of the region (Zachos & Habel 2011). About half of the known biodiversity in India, particularly endemics, is contributed by the 13% land area of the Indian Himalayan Region (IHR). The phytogeographical complexity in the present Jammu & Kashmir, located on the northwestern side of the Himalaya, contributes significantly to various life forms. On account of its floristic status, the Kashmir Himalaya is a part of Himalayan biodiversity hotspot, and it is also considered to be vulnerable to climate change and thus species extinction (Rashid et al. 2015).
Several scholars over the course of time have made significant contributions to floristic knowledge of the Himalayan region: Hooker (1872Hooker ( -1897; Lambert (1933); Javeid (1966Javeid ( , 1978Javeid ( , 1979; Hajra (1983); Polunin & Stainton (1984); Kachroo (1993); Singh & Kachroo (1994); and Malik et al. (2010). However, critical taxonomic knowledge about the Kashmir Himalaya is still poor. In addition, a detailed study on the altitudinal distribution of taxa across the forest types is lacking. Consequently, the present study was undertaken to document the floristic diversity of the area, and to highlight its conservation significance.

Study area
The study area spans over five districts of the Kashmir valley (33.513-34.659 Peel et al. 2007) with four distinctive seasons, i.e., spring, summer, autumn, and winter. Climate data from the last 38 years revealed that Kashmir valley experiences an annual mean minimum and maximum temperature of 5.4 ± 0.4 °C and 17.6 ± 0.8 °C (Dad et al. 2021). Furthermore, the mean annual rainfall is 1005.5 ± 197.6 mm (Dad et al. 2021. About 46% of precipitation occurs during pre-monsoon, followed by south-west monsoon (27%), winter monsoon (25%), and post-monsoon (8%). Disturbances posed by the Mediterranean Sea during winter lead to frequent rain and snowfall in the valley. The period of snowfall extends from October-March. Geologically, the study area consists of rocks chiefly composed of slates, phyllites and quartzites (Krishnan 1982). The predominant soil orders are entisols, inceptisols, alfisols, and mollisols (Mahapatra et al. 2000;Sidhu & Surya 2014).
Mixed coniferous (MC) forest, commonly referred to J TT  (Dar & Sundarapandian 2016). Epiphytic moss and lichen cover the trunk and lower branches of emergent tree species. Activities such as grazing, extraction of plants and plant materials of economic and medicinal value, firewood collection, illegal logging, etc., contribute to forest degradation. The subalpine forest (SA) forms a transition between MC forest and alpine scrub or grassland from 2,900-3,500 m. Abies pindrow is a characteristic and dominant species intermixed with Betula utilis D.Don. Rhododendron spp. occur as undergrowth or form individual stands. The species of Primulaceae, Ranunculaceae, and Compositae constitute the main understory herbaceous vegetation. The subalpine forest is equally subjected to anthropogenic disturbances like the other forest types besides heavy winter snowfall as a natural disturbance (Gairola et al. 2009).

Sampling, herbarium preparation, and data analysis
A reconnaissance floristic survey was undertaken in the landscape between the elevation gradient of 1,500 m and 3,800 m to understand the forest types and composition. Three coniferous forests of Kashmir Himalaya: BP, MC, and SA (Champion & Seth 1968) were identitifed in the region. Botanical explorations were undertaken during 2019 (March-July) and 2020 (May-August) by employing a random sampling approach considering the accessability and forest types. During the survey, plants such as trees, shrubs and herbs were documented and voucher specimens were collected. Specimens were processed (pressing, drying, chemical treatment, and mounting) following recommended standard techniques (Rao & Sharma 1990), and examined and identified at the Centre for Biodiversity

J TT
and Taxonomy, University of Kashmir. The voucher specimens were deposited at the Department of Ecology and Environmental Sciences Herbarium, Pondicherry University. The Plant List (TPL; http://www.theplantlist. org/) was referred for updated binomial nomenclature and the author names. Angiosperm Phylogeny Group III (APG III) Classification (2009) and Chase & Reveal (2009) for angiosperms and Gymnosperms were followed for categorizing families. Khuroo et al. (2007) was referred for the origin and alien status of flora. Various information sources were explored to acquire Himalayan and global records of inventoried taxa, including Himalayan flora literature (Hooker 1872(Hooker -1897Polunin & Stainton 1984), Tropicos (http://www.tropicos.org/), India Biodiversity Portal (https://indiabiodiversity.org/), Flowers of India (http://www.flowersofindia.net/) and Plants of the World online (http://www.plantsoftheworldonline. org/).
Three families in Magnoliophyta with greater contribution to species richness include Compositae (28 taxa, 13.86%) and Apiaceae and Rosaceae (13, 6.44% each). Families with ten or more species (besides above three) include Lamiaceae, Leguminosae, Poaceae (11, 5.45% each), and Ranunculaceae (10, 4.95%) ( Figure  2). Species-rich genera, i.e., Artemisia, Potentilla, Viola, and Saussurea contributed 16 (7.92%) taxa. Majority of families (26, 47.27%) and genera (108, 72.97%) are monotypic with a single taxon. Among Pinophyta, Pinaceae (four taxa) and Cupressaceae (two taxa) are predominant families, whereas Juniperus is the principal genus contributing two taxa. Pteridophyta is represented by Pteridaceae (two taxa) and Equisetaceae (one taxon), and all the three genera (Adiantum, Equisetum, and Pteris) contributed equally, i.e., one species. In contrast to tree and understory herb vegetation, all shrub families and genera contributed one species each. The number of taxa varied among the forest types and corresponding elevation due to the uneven distribution of taxa (

Determination of phytogeographic distribution and taxa status
The distribution of most of the recorded taxa is confined to the northern temperate regions. However, 24 taxa restricted their distribution to the Himalayan landscape (

DISCUSSION
The floristic survey revealed 272 taxa from 196 genera and 64 families categorized in three life-forms, i.e., trees and understorey shrubs and herbs (Table 1 & 2). The number of taxa reported in the present study was greater than most of the floristic studies in temperate Kashmir Himalaya (Shaheen et al. 2012;Mir et al. 2019;Malik et al. 2021) and other Himalayan studies (Ahmad et al. 2020;Asif et al. 2020;Tiwari et al. 2020) and also elsewhere (Bai et al. 2011). Compositae and Apiaceae constituted species-rich families in this survey. These families were also well represented in other studies of the Kashmir Himalaya: Asif et al. (2020) Betula forests in northwestern Kashmir Himalaya; Dar & Sundarapandian (2016) forests of western Himalaya, and elsewhere Devi et al. (2014) northwestern Himalaya. Variation in species distribution among the forest types/altitudinal zones could be due to micro-climatic heterogeneity resulting from a change in elevation, slope, and other ecological gradients (Körner 2007), besides evolutionary     effects (Qian et al. 2015). The variation in microclimate would have enabled the taxa to adjust to a wide range of niches along elevation and a variety of pre-adapted lineages to colonize in the mountain ranges. Therefore, it can be considered that climatic factors differentiate taxa as indicated by resilience developed over their evolutionary past, with these phylogenetic variations, in turn, deciding species heterogeneity (Wiens & Donoghue 2004;Rana et al. 2019). One of the prerequisites for biodiversity conservation is to determine the areas of particular importance in the context of taxa vulnerability and characteristic habitats and critically evaluate the same, thus enabling them to prioritize these areas for further consideration (Spehn 2011). In the present study, the situation for seven (2.57%) taxa categorized under threatened, i.e., Saussurea costus & Aconitum chasmanthum (CR), Trillium govanianum, Aconitum heterophyllum, Taxus wallichiana, & Atropa acuminata (EN), and Cypripedium cordigerum (VU) were found occasionally in the present study and requires immediate conservational priorities across the landscape. Besides climate change and overgrazing, the species in high demand for traditional medicinal and pharmaceutics has led to their extensive collection and illegal trading, thus pushing them closer to extinction (Devi et al. 2014;Nowak et al. 2020). The sustainability of such flora is imperative across the landscape. Ecological rehabilitation, site-specific in particular should be accomplished by re-vegetating degraded sites with natural vegetation. Existing management regulations must be examined in order to adopt strict guidelines to enhance efficiency in decisionmaking and avoid fraud. Extensive quantitative plant diversity inventories and biogeographical explorations ought to be directed on the threatened flora to identify its abundance and frequency. Additionally, ex situ management methods must be in place in addition to the in situ conservation programmes. Overall, from our study we infer that all three types of coniferous forests are rich in flora, demonstrating their importance for conservation. We hope that our results will serve as a benchmark for potential future studies on plant ecology of the area. With notable plant diversity, Kashmir Himalaya is probably a suitable site for further investigations. Moreover, because Kashmir Himalayan forests face threats due to various anthropogenic activities, qualitative data of documented flora will help