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This study elucidates the distribution of plants in Great Himalayan National Park (GHNP), India, in current and different future climate change scenarios. The distribution of plants and habitat suitability in GHNP due to climate change was analyzed by MaxEnt, species distribution model (SDM) algorithm. In this study, species presence records were retrieved through field survey and published literature. We have projected the distribution of 44 plant species using MaxEnt and tested whether GHNP is performing well in conserving the plant species. Initially, we have constructed a model for each species and created the habitat suitability map from average of ascii files and later we added the maps of all species in order to make binary map to show the species richness in the selected climate scenarios. The model was created using the HADGEM-2 global circulation model in 2050 and 2070 years by using climate change situations of RCP 2.6 and RCP 8.5. The area under curve (AUC) values in the final models of 44 plant species were in the range 0.70-0.97 that indicates statistically significant results. The model identified precipitation of driest month followed by altitude and annual mean temperature as most determining variables in the distribution of plants of GHNP in selected climate scenarios. In the present study, we found that overall suitable habitat increased for nine species, decreased for thirty-four, and unchanged for one plant species in terms of percent area change from current to future scenarios. So these nine species were found to be more adaptable towards changing climate than the other plant species in this study. The species richness was high in western and southwestern parts of GHNP in the current scenario, however under future climatic scenarios, species richness shows a decreasing trend. Based on our findings, it can be concluded that GHNP should be prioritized for conserving the plant species., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The estuaries provide the key pathway for travelling carbon across the land-ocean interfaces and behave as both source and sink of greenhouse gases (GHGs) in water-atmosphere systems. The sink-source characteristics of estuaries for GHGs vary spatially. The primary driving factors are adjacent ecologies (agriculture, aquaculture, etc.) and proximities to the sea. To study the sink-source characteristics of estuaries for GHGs (methane (CH 4 ), nitrous oxide (N 2 O) and carbon dioxide (CO 2 )), the water samples were collected from 53 different locations in the estuaries for estimation of dissolved GHGs concentration and air-water GHGs exchanges. The locations represent five zones (Zone I, II, III, IV and V) based on the type and degradation status of mangroves (degraded and undisturbed), anthropogenic activities, and distance from the sea. Zone I, III, V represents to the degraded mangroves far from sea, whereas, Zone II, IV surrounded by undisturbed mangroves and nearer to sea. The average dissolved CH 4 concentrations were higher in the estuaries which were adjacent to degraded mangroves (154.4 nmol L -1 ) than undisturbed mangroves (81.7 nmol L -1 ). Further, the average dissolved N 2 O concentrations were 48% higher in the estuaries nearer to degraded mangroves than that of undisturbed ones. Among the degraded mangrove sites, the dissolved CO 2 concentrations were higher at Zone I (30.1 μmol L -1 ) followed by Zone III and IV, whereas in undisturbed sites, it was higher in Zone IV (22.3 μmol L -1 ) than Zone II (17.6 μmol L -1 ). Among the 53 locations, 36, 51 and 33 locations acted as a sink (negative value of exchanges) for CH 4 , N 2 O and CO 2 , respectively. The higher sink potential for CH 4 was recorded to those estuaries adjacent to undisturbed mangroves (-791.69 μmol m -2  d -1 ) than the degraded ones (-23.18 μmol m -2  d -1 ). Similarly, the average air-water N 2 O and CO 2 exchanges were more negative in the estuaries which were nearer to undisturbed mangroves indicating higher sink potential. The pH, and salinity of the estuary water were negatively correlated with air-water CH 4 and N 2 O exchanges, whereas those were positively correlated with CO 2 exchanges. Significantly lower dissolved GHGs and air-water GHGs exchange was observed in the estuaries adjacent to the undisturbed mangrove as compared to the degraded mangrove. The reason behind higher sink behaviours of estuaries nearer to undisturbed mangroves are higher intrusion of seawater, less nutrient availability, higher salinity, low carbon contents and alkaline pH compared to estuaries adjacent to degraded mangroves and far from sea., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The present study focuses on the spread of rubber monoculture in the state of Tripura during past three decades (1990-2021) in the northeast region of India which is known for its rich biodiversity, shifting cultivation, and extensive forest dynamics. Earth observation (EO) data of seven time periods from Landsat missions (1990, 1995, 2000, 2004, and 2009) and Sentinel-2 (2016 and 2021) were the main source for mapping and were supplemented with MODIS-EVI temporal spectral profiles, GEDI-derived vegetation heights (2019), and Google Earth high-resolution historical images for additional cues to support discrimination, mapping, and accuracy assessment. The methodology for rubber used its unique phenology from spectral-temporal profile and multi-year comparison of patches and their dynamics for age-class mapping. The results indicate that in the state of Tripura (geographic area 1.08 Mha), the area under rubber increased from 0.3% in 1990 to 8.9% of the geographic area in 2021. The overall classification accuracy for the maps created for the years 1990, 1995, 2000, 2004, 2009, 2016, and 2021 was 84.2%, 83.9%, 84.8%, 88.0%, 86.0%, 86.7%, and 89.5%, respectively. New areas under rubber originated from various land cover classes including open forests, shifting cultivation lands, and scrub. Recent expansion has resulted in 84.3% of rubber plantations under the 10-year age class. Implications of this transformation of the natural landscape, biodiversity and biomass, and carbon pool assessment are discussed., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The main focus in biodiversity is to conserve species diversity with specific emphasis on endemic species. This study has analysed the distribution of endemic floral and faunal species and their representativeness in protected areas of India. The number of endemic species has been estimated as 29787 (30.35%) and 12696 (26.33%) of Indian fauna and flora respectively. Overall, 2055 animal species and 1983 plant species were discovered from India from 2009 to 2018. The number of new distributional records to India reported during the last decade is 1242 species of plants and 1086 species of animals. The species discovery data indicate that there are more species yet to be described. According to the Cramer coefficients, the elevation was strongly correlated with endemism, followed by precipitation, temperature, land cover, and biogeographic zone. The study of endemic floral and faunal species including new species and protected areas provides the first prototype national gap analysis in assessing the representativeness of coverage of protected areas. The patterns of geographic distribution of endemic species and the gap analysis present a novel finding for conservation priorities. The highest number of new species was discovered from protected areas i.e. Periyar, Mundathurai, Khangchendzonga, Mehao, Thattekadu Bird, Eravikulam, Mukurthi, Saddle Peak, Malabar, and Anamalai. Although the total area protected is significant in India, their geographic coverage is almost the contrary to patterns of endemism. The results provide a valued direction for the advancement of management strategies for biodiversity conservation.

Tropical mangrove represents one of the most threatened ecosystems despite their huge contribution to ecosystem services, carbon (C) sequestration and climate change mitigation. Understanding the system in light of seasonal fluctuations on greenhouse gases (GHGs) emissions due to human interferences and the tidal effect is important for devising site-specific real-time climate change mitigation strategies. In order to capture the seasonal variations, the three modes of transport of GHGs through pneumatophore, ebullition as bubbles and water-soluble diffusion was quantified. The three unique techniques for the gas collection were used to estimate the GHGs [methane (CH 4 ), nitrous oxide (N 2 O) and carbon dioxide (CO 2 )] emission, at three degraded-mangrove sites in Sundarban, India. We identified three degraded mangrove ecologies based on the remote sensing data of 1930 and 2013 (mangrove-covered area in Sundarban; 2387, 2136 km 2 , respectively). Samples were collected and analyzed for four seasons [winter (November-January), summer (February-April), pre-monsoon (May-June) and monsoon (July-October)], at three representative sites (Sadhupur, Dayapur, and Pakhiralaya). Monsoonal CH 4 and CO 2 fluxes (0.353 ± 0.026 and 64.5 ± 6.1 mmol m -2 d -1 , respectively) were higher than winter and summer. However, the soil labile C pools showed the opposite trend i.e. more in summer followed by winter and monsoon. In contrast, the N 2 O fluxes were more during summer (54.2 ± 3.2 μmol m -2 d -1 ). The stagnant water had higher dissolved GHGs concentration compared to tidewater due to less salinity and a long time of stagnation. The mode of transport of GHGs through pneumatophore, ebullition, and water-soluble diffusion was also significantly varied with seasons, soil‑carbon status and tidewater intrusion. Therefore, seasonal fluctuations of GHGs emission and tidal effect must be considered along with soil labile C pools for GHG-C budgeting and climate change mitigation in the mangrove ecosystem., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The land, oceans, and atmosphere are tightly linked and form the most dynamic component of the climate system. Studies on terrestrial and ocean science enhance the understanding on the impacts of climate change. Across India and the world over, human-driven land use and climate changes are altering the structure, function, and extent of natural terrestrial ecosystems and in turn regional biogeochemical feedbacks. In this special issue, we present 29 manuscripts; those discuss wide-ranging aspects of terrestrial and oceanic characterization and dynamics. These contributions are based on selected presentations made at the 2nd International Workshop on Biodiversity and Climate Change (BDCC-2018) held on 24-27 February 2018 at the Indian Institute of Technology Kharagpur, India. The manuscripts are arranged in five sections such as Ecological Assessment, Plant Invasion, Carbon Dynamics, Ecosystem Characterization, and Ocean Dynamics. We realized that the utility of satellite remote sensing data has been emerging as a dominant trend in environmental monitoring and assessment studies in India.

India is home of the largest remaining population of the Asian elephant (Elephas maximus L.) in the South and Southeast Asia. The forest loss and fragmentation is the main threat to the long-term survival of Asian elephants. In the present study, we assessed forest loss and fragmentation in the major elephant ranging provinces in India, viz., north-eastern, north-western, central, and southern since the 1930s. We quantified forest cover changes by generating and analyzing forest cover maps of 1930, 1975, and 2013, whereas fragmentation of contiguous forest areas was quantified by applying landscape metrics on the temporal forest cover maps. A total of 21.49% of the original forest cover was lost from 1930 to 1975, while another 3.19% forest cover was lost from 1975 to 2013 in the elephant ranges in India. The maximum forest loss occurred in the southern range (13,084 km 2 ) followed by north-eastern (10,188 km 2 ), central (5614 km 2 ), and north-western (4030 km 2 ) elephant ranges in the past eight decades. The forests in the central range were the most fragmented followed by southern, north-eastern, and north-western elephant ranges. The forest fragmentation in the southern range occurred at the fastest rate than central, north-eastern, and north-western ranges. The core forest areas shrunk by 39.6% from 1930 to 2013. The causative factors of forest change and situation of elephant-human conflict have been discussed. Study outcomes would be helpful in planning effective conservation strategies for Asian elephants in India.

Forest fire is considered as one of the major threats to global biodiversity and a significant source of greenhouse gas emissions. Rising temperatures, weather conditions, and topography promote the incidences of fire due to human ignition in South Asia. Because of its synoptic, multi-spectral, and multi-temporal nature, remote sensing data can be a state of art technology for forest fire management. This study focuses on the spatio-temporal patterns of forest fires and identifying hotspots using the novel geospatial technique "emerging hotspot analysis tool" in South Asia. Daily MODIS active fire locations data of 15 years (2003-2017) has been aggregated in order to characterize fire frequency, fire density, and hotspots. A total of 522,348 active fire points have been used to analyze risk of fires across the forest types. Maximum number of forest fires in South Asia was occurring during the January to May. Spatial analysis identified areas of frequent burning and high fire density in South Asian countries. In South Asia, 51% of forest grid cells were affected by fires in 15 years. Highest number of fire incidences was recorded in tropical moist deciduous forest and tropical dry deciduous forest. The emerging hotspots analysis indicates prevalence of sporadic hotspots, followed by historical hotspots, consecutive hotspots, and persistent hotspots in South Asia. Of the seven South Asian countries, Bangladesh has highest emerging hotspot area (34.2%) in forests, followed by 32.2% in India and 29.5% in Nepal. Study results offer critical insights in delineation of fire vulnerable forest landscapes which will stand as a valuable input for strengthening management of fires in South Asia.

Deforestation and fragmentation are important concerns in managing and conserving tropical forests and have global significance. In the Indian context, in the last one century, the forests have undergone significant changes due to several policies undertaken by government as well as increased population pressure. The present study has brought out spatiotemporal changes in forest cover and variation in forest type in the state of Odisha (Orissa), India, during the last 75 years period. The mapping for the period of 1924-1935, 1975, 1985, 1995 and 2010 indicates that the forest cover accounts for 81,785.6 km(2) (52.5 %), 56,661.1 km(2) (36.4 %), 51,642.3 km(2) (33.2 %), 49,773 km(2) (32 %) and 48,669.4 km(2) (31.3 %) of the study area, respectively. The study found the net forest cover decline as 40.5 % of the total forest and mean annual rate of deforestation as 0.69 % year(-1) during 1935 to 2010. There is a decline in annual rate of deforestation during 1995 to 2010 which was estimated as 0.15 %. Forest type-wise quantitative loss of forest cover reveals large scale deforestation of dry deciduous forests. The landscape analysis shows that the number of forest patches (per 1,000) are 2.463 in 1935, 10.390 in 1975, 11.899 in 1985, 12.193 in 1995 and 15.102 in 2010, which indicates high anthropogenic pressure on the forests. The mean patch size (km(2)) of forest decreased from 33.2 in 1935 to 5.5 in 1975 and reached to 3.2 by 2010. The study demonstrated that monitoring of long term forest changes, quantitative loss of forest types and landscape metrics provides critical inputs for management of forest resources.

Twelve hundred rice samples consisting of paddy (675) and milled rice (525) were collected from 20 states across India. These samples were assessed for Aspergillus spp. infection on selective medium and aflatoxin B(1) (AFB1) by indirect competitive ELISA. In this investigation, Aspergillus flavus contamination dominated in all the seed samples. The other major contaminants were Aspergillus niger, Aspergillus ochraceus and Aspergillus parasiticus. Out of 1200 rice samples, 67.8% showed AFB1 ranging from 0.1 to 308.0 microg/kg. All the paddy samples from Chattishgarh, Meghalaya and Tamil Nadu showed AFB1 contamination. Milled rice grains from different states showed below the permissible levels of AFB1 (average 0.5-3.5 microg/kg). Eighty-two percent of samples from open storage that were exposed to rain showed AFB1 contamination followed by one-year-old seed. Out of 1200 samples, 2% showed AFB1 contamination above the permissible limits (>30 microg/kg). This is the first comprehensive report of aflatoxin contamination in rice across 20 states in India.

The rural folk of North Andaman, India use the traditional medicine for their primary health care. Folklore medicinal uses of 72 interesting medicinal plant species along with botanical name, local name, family, habit, part used, disease for which the drug is administrated, mode of administration are presented. These 72 plant species which provide the crude drugs pertain to 67 genera and 43 families of Magnoliophyta from tropical rainforests. These plants used to cure 40 ailments. Most remedies were taken orally, accounting for 76% of medicinal use. Most of the remedies were reported to have been from trees (55.6%) and herb (22.2%) species. The most widely sought after plant parts in the preparation of remedies in the areas are the stem bark (33.8%) and root (23.9%).

An ethnobotanical survey was carried out among the ethnic community (Didayi) in Malkangiri district, Orissa. A total of 53 medicinal plant species belonging to 34 families and 52 different species are described under this study.

Inadequate information about the genetic structure of the polyphagous Rhizoctonia solani has made sheath blight resistance breeding a difficult task. To assess the variability in the Indian populations of sheath blight fungus, 18 isolates were collected from different rice growing regions of India and analyzed for virulence and electrophoretic profiles of 13 isozymes. The virulence spectrum of all 18 isolates was examined on susceptible IR50 and tolerant Swarnadhan varieties, based on which the isolates could be grouped as highly virulent, moderately virulent or avirulent. A total of 11 enzyme systems with 153 electrophoretic phenotypes were applied to characterize the genetic variation among the isolates. Cluster analyses based on isozyme patterns resulted in one major cluster comprising 16 virulent isolates, with two avirulent isolates loosely linked to this at 0.13 similarity. Isozyme systems of esterases (both alpha and beta) and 6-phosphogluconic dehydrogenase could be used to fingerprint the individual isolates.