Flowering Calendar of the Macrophytes of Keibul Lamjao National Park, Loktak Lake, Manipur, India

Seasonal variations in the water quality of a tropical wetland dominated by floating meadows and its implication for conservation of Ramsar wetlands

Keibul Lamjao National Park (KLNP), Loktak lake Manipur, north-east India which is one of the 25 Ramsar sites of international importance and the biggest fresh water Lake in India. Macrophytes of the floating Phumdi mat environment of KLNP play an important role in the aquatic environment. An investigation was planned during the period of about three years from March, 2010 to December 2012, to study the diversity pattern of habitats of macrophytes available in six study sites of KLNP viz., 1.Kumbi, 2.Khordak, 3.Keibul, 4.Toya, 5. Nongmaikhong and 6. Sargam. All total 85 dominant plant species were recorded. Maximum plant species (49) was observed in Site-1 Kumbi (Altitude-780m) and minimum (27) in Site-3 Keibul (Altitude-772). The variation of plant species may be because of the slight variation of altitude. As the six study sites are distributed as floating aquatic environment in KLNP Loktak Lake, there is favourable place of the plants in higher altitude and altitude represents a complex gradient along which many environmental variables change concomitantly. In all the six study sites, common distribution of ten dominant plant macrophytes viz., Ageratum conizoides, Hedychium coronarium, Leersia hexandra, Oenanthe javanica, Phragmites karka, Polygonum sagittatum, Saccharum munja, Thelypteris interrupta and Zizania latifolia was noticed. Individual dominant plant was recorded in other sites also viz., Azola piñata in site-6; Xanthium atrumarium, Polygonum orientale, Dichrocephala latifolia and Cymbopogon citratus in site-2; Arundo plinii, Cuscuta reflexa, Gnaphalium luteo-album, Hydrilla verticillata, Marsilia minuta, Saccolepis interrupta, Selvenia cuculata and Utricularia spp. in site-1. Variation of IVI value of dominant plant species was observed in this study. Even though 85 dominant plants were selected for all the 6 sites, however, maximum plant richness expressed in IVI was recorded in case of Zizania latifolia (Site-5, IVI-87.5) and minimum IVI in case of Xanthium strumarium (Site-2, IVI-1.13). The diversity pattern and habitats of macrophytes in KLNP Phumdi environment might be due to water availability along the altitudinal gradient and other environmental factors suited in the study sites and expected to be an important factor affecting the survival and fecundity of plant population. We need to conserve the natural habitat of KLNP thereby maintaining the luxuriant growth of the seasonal and perennial, macrophytes, so as to maintain the natural flora and fauna of the park. These plants are the food of man and animal therefore, it needs a proper care and attention to protect them from over exploitation. Considering the diversity pattern of habitats of Macrophytes in KLNP, a floating mat Phumdi environment with high floral diversity and unique vegetation assemblage, it has been suggested that this track and adjoining sites should be declared as ecologically sensitive area not only the World Heritage Site.

Loktak Lake is the largest fresh water Lake in the North-eastern India. Keibul Lamjao National Park (KLNP) is a floating-mat (Phumdi) park inside the Lake. Study deals with the inter-related approaches: micobiological study, free-listing, participant observation and preference ranking of the six study sites of KLNP. Generally, plant collection per day was about 600 kg of Hedychium coronarium J. Koenig which were extracted from the park and found to be the most preferable species; while Persicaria sagittata (L.) H. Gross, as the least among the selected plants. Microbiological analysis of water for the six study sites recorded high pollution as evidenced by high values of Standard Plate Count (SPC) for bacteria ranging from 73,500-96,500 and microbial analysis of MPN (Most Probable Number) of coliform bacteria varies between100 and 320/100 ml and faecal coliform 95 and 200/100 ml. Free CO2 concentrations varied at the surface from 2-60 mg/l and 6-70 mg/l at the bottom of the park. In the KLNP environment the higher CO2 and lower concentrations of dissolved oxygen (DO) might be due to the floating mat (Phumdi) nature, in which light and exchange of gases does not occur as it does in the natural water bodies.

Keibul Lamjao National Park (KLNP), a floating park in Loktak Lake, Manipur (India) was studied from Winter (WIN) to Post Monsoon (POM) for its zooplankton composition and some selected water parameters. The resultant data were subjected to multivariate techniques–Principal Component Analysis (PCA) and Canonical Correspondence Analysis (CCA). Analyses of water parameters with PCA revealed that the first PC axis (PC1) accounts for maximum variance in the seasonal data, explaining a variability of 91%. The PCA revealed that the seasonal variability in water parameters was due to the wet and dry cycle of seasons and the stations were distinguished on the basis of transparency and turbidity. Zooplankton abundance was dominated by copepods followed by cladocerans. Temporally, abundance of copepods reached a maximum during Post-monsoon (POM) (3 880 ind./L). Spatially, S6 was found to be most abundant of the other stations in zooplankton. Copepodites and nauplii larvae were the major components of zooplankton. The Rotifera were the least abundant among the three zooplankton groups. Brachionus formed the major component of Rotifera zooplankton at all the stations during the study period. In the Cladocera, Macrothrix was present during all the four seasons, while Pleuroxus, Oxyurella, Kurzia and, Diaphanosoma were rare. The CCA shows that maximal temporal variability in zooplankton abundance was explained by temperature and rainfall. ANOVA revealed no significant diff erence in mean zooplankton abundance among the seasons, but there was a statistically significant diff erence among the sites.

<div><p><em>Flowering calendar of a particular area will give the information of the period and duration of flowering among plants. The purpose of the study is to investigate the presence of the habitat of some dominant macrophytes in Keibul Lamjao National Park (a Ramsar site) which have ethnobotanical relationships with human beings (the lake dwellers in particular and tourist in general) and wild animals. Flowering calendar of six study sites viz., Keibul, Nongmaikhong, Kumbi, Khordak, Sargam and Toyaching were studied and monthly flowering calendars were taken for two year period (2010 to 2011). Flowering calendars of the macrophytes were surveyed by following standard methodologies and comparison of the stages of flowering period of 6 study sites was incorporated. Maximum number of flowering plants (44) was recorded in Sargam, Khordak (32), Kumbi (30), Nongmaikhong (29) during the period September to November. Whereas, Toyaching reached 35, Keibul recorded lowest plant numbers (14) during the period June to August. Four plant species viz., Ageratum conyzoides, Alternanthera philoxeroides, Leersia hexandra and Hedychium coronarium were found throughout the year in all the 6 sites. From the findings, it can be concluded that flowering calendar will give the information of plants which are used as fodder for the wild animals like Sangai (Rucervus eldii eldii McClelland), an endangered deer species in this globe and ethnobotanically important plants of the lake dwellers as food, medicinal plants and allergens, thereby maintaining health status of man and animals. Conservation is required by controlling the human anthropogenic harassments, thereby maintaining the luxuriant growth of the seasonal and perennial, macrophytes observed during the study of flowering calendar, so as to maintain and conserve the natural flora and fauna of the park.</em></p></div>

The presence of floating islands is a unique characteristic of Loktak Lake. Floating islands play a significant role in ecosystem services and ecological processes and functioning. Rapid urbanization, industrialization, and a demand for more resources have led to changes in the landscape patterns at Loktak Lake in past three decades, thereby degrading and threatening the fragile ecosystem. The aim of the present study is to assess the changes in land use practices of the Phumdis by analyzing data from the past 38years with remote sensing techniques. Landsat images from 1977, 1988, 1999 and an Indian remote sensing image from 2015 were used to assess the land use/land cover changes. The methodology adopted is a supervised classification using the maximum likelihood technique in ERDAS software. Five land used classes were employed: open water bodies, agricultural areas, Phumdis with thick vegetation, and Phumdis with thin vegetation and settlements. The results indicate that the highest loss of land used class was in Phumdis with thin vegetation (49.38km2) followed by Phumdis with thick vegetation (8.59km2), while there was an overall increase in open water bodies (27.00km2), agricultural areas (25.33km2), and settlement (5.75km2). Our study highlights the loss of floating islands from the Loktak as a major concern that will lead to the destruction of the only "floating national park in the world." There is a high probability of extinction of the Sangai, an important keystone species found in the Indo-Burma biodiversity hotspot, if floating islands are not protected through sustainable development.

ABSTRACTThe assessment of nutrient and heavy metal accumulation in lake sediments is essential for understanding their role in the ecohydrological dynamics of lake ecosystems, as sediments can function both as a sink and source of nutrients, metals and various contaminants aquatic ecosystem. The main objective of this study was to evaluate the concentrations of nutrients and heavy metals and their accumulation in the sediments across different sampling locations of Loktak Lake and to compare them against geochemical background values and sediment quality guidelines. The key findings of the study revealed substantial nutrient accumulation in sediments from the Keibul Lamjao National Park site, which can be attributed to the decomposition of organic matter from dense floating vegetative masses called ‘Phumdis’. Iron concentrations in sediments were significantly high, ranging from 909.83 to 1004 mg/kg and its enrichment is likely due to diffused surface runoff from the iron‐rich soils from the surrounding catchment entering the lake through feeder rivers and other anthropogenic influences. The average metal concentrations were in the order of Fe > Mn > Zn > Cu, and all values were below the average shale concentrations and the Interim freshwater Sediment Quality Guidelines (ISQG) set by the Canadian Council of Ministers of the Environment (CCME). The evaluation of the heavy metal pollution status of the lake sediments based on various pollution indices such as the contamination factor, degree of contamination, modified degree of contamination, geoaccumulation index, pollution load index and potential ecological risk index, suggested an overall low level of metal pollution in the sediments of Loktak Lake. The findings of this study provide a crucial baseline for understanding on the sediment‐associated nutrient and metals dynamics in Loktak Lake which can aid in the formulation of long‐term lake management strategies for preserving the ecological integrity and health of this precious lake ecosystem of the region.

Aquatic insect diversity of a protected area, Keibul Lamjao National Park in Manipur, North East India

Manipur is a biodiversity rich state located in the northeastern part of India that borders Myanmar. Situated within the western portion of the Indo-Burma biodiversity hotspot, the state has a large number of endemic and endangered species. The state is also prone to habitat destruction due to rapid clearing of forest for shifting cultivation, which is a common practice in the hill districts for agriculture and collection of firewood and timber. In the valley districts, the entire forest areas were converted to agricultural fields leaving only a few remaining green spaces, such as the sacred groves locally known as Umang Lais, small hillocks, and Keibul Lamjao National Park.

The Sangai (Rucervus eldii eldii) is found only in the Manipur’s Keibul Lamjao National Park (KLNP). The Sangai is peculiar, being the "only deer to adapt to a floating wetland habitat." The reasons why there is threats to the Sangai's very existence will, for the purpose of this paper, assume that there are efforts to learn more about the basic characteristics that define the deer, regarding its population and approaches to conservation. Despite a population recovery from near-extinction in 1960s, the species remains in danger of extinction due to its habitat deterioration by Loktak Hydro Electric Project, loss of genetic diversity, poaching and disturbance on the overall ecosystem of Loktak Lake by human activities.

The Sangai deer (Rucervus eldii eldii) is an endangered species which is found only in KeibulLamjao National Park, Manipur (India) with an area of 40 km2. Selection of observation point and direct observation method were utilized to record certain behavioral pattern shown by the Sangai deer. Determination of food resources were carried out to identified feed species during the observation hour. The finding of the present study shows that the behavioral activities were notice more in the morning (dawn) than evening (dusk). The most favorable food by Sangai deer were Zizania latifolia (Kambong), Pragmitis karka (Tou), Saccharum munja (Khoimom), Carex cruciata (Humdang), Learsia hexandra (Hup), Alpinanigra (Pullei) and Hydechiumcoronarium (Loklei). Amongst the favorable food species, the most preferable food by the Sangai deer is Zizania latifolia while some of the individuals were seen consuming ashes (Tanggoi) during the observation. Intrusion of domestic animals within the park area may lead to severe calamities which then lead to the spread of many harmful diseases to Sangai deer and its inhabitants. Shyness of animal and sensitive behaviors of Sangai deer was observed. Questionnaire surveys were carried out among 40 respondents. The result suggested that the status of feeding must be taken care so that there should not be any alteration or changes in their behavior due to intrusion, local vegetables collector and disturbances.

Assessing seasonal variation of diffusive nitrous oxide emission from freshwater wetland in Keibul Lamjao National Park, Manipur Northeast India

The hog deer (Axis porcinus) is threatened by habitat alteration, fragmentation, and poaching, which have led to a drastic decline of its wild population. Two subspecies of A. porcinus have been described from its distribution range. A. p. porcinus is reported to occur from Pakistan along the Himalayan foothills through Nepal, India and Myanmar, and A. p. annamiticus is found in Thailand, Indo-China, Laos, Cambodia, and Vietnam. However, the current distribution range of A. p. annamiticus is still unclear. We used the partial control region (CR) of mitochondrial DNA (mtDNA) and seven microsatellite loci to investigate the intra-species structure, differentiation, and demographic history of hog deer populations from three landscapes, the Terai Arc, Northeast, and Indo-Burma (Keibul Lamjao National Park (KLNP), Manipur, India) landscapes. We also carried out divergence time estimation using the complete mitogenome. The level of variation was ~4%, and the time of divergence of the KLNP population and the other Indian populations was about 0.22 Mya, i.e., during the last glaciation periods of the Late Pleistocene/Early Holocene. The KLNP haplotypes of the control region were shared with the Southeast Asian subspecies, A. p. annamiticus. The results of the investigations of the microsatellite loci supported the mtDNA results unambiguously. Two genetically distinct lineages are found in India: one is found from the Terai Arc to Assam (A. p. porcinus) and the other in Manipur (A. p. annamiticus). The genetic diversity in KLNP was low and exhibited a higher degree of genetic differentiation compared with major Indian populations. The Bayesian skyline plots indicated that after a long phase of historic demographic stability, the populations of both the lineages of hog deer suffered pronounced declines during the period from ~800 years BP to 5000 years BP. In summary, our finding provided evidence that the KLNP population is probably a prime, isolated and sustaining stock of A. p. annamiticus and should be managed as evolutionarily significant units (ESUs).

An in-depth understanding of carbon dynamics and ecosystem productivity is essential for conservation and management of different ecosystems. Ecosystem dynamics and carbon budget are assessed by estimating net ecosystem production (NEP) across different global ecosystems. An ecological productivity assessment of forest and floating meadow ecosystems in Keibul Lamjao National Park (KLNP), Manipur, North East India, was conducted using the multi-criteria decision-making process namely, gray relational analysis (GRA). The analysis was performed on 24 selected criterions classified either as "higher-the-better" or "lower-the-better" based on their degree of influence on the carbon budget. Floating meadows exhibited a higher production of aboveground and belowground biomass and a higher total mortality and decay. Furthermore, the study found that floating meadows exhibited a higher soil organic carbon (SOC) and net soil organic matter (SOM) than the forest ecosystem. The forest ecosystem showed higher total respiration (RT), heterotrophic respiration (RH), and autotrophic respiration (RA) than floating meadows. Floating meadows exhibited a higher net primary productivity (NPP) of 616.49 ± 33.87 gCm-2year-1 than the forest ecosystem, which has a NPP of 566.64 ± 65.26 gCm-2year-1. Similarly, floating meadows have higher NEP (495.25 ± 36.46 gCm-2year-1) than forest ecosystems (418.39 ± 65.76 gCm-2year-1). These characteristics have a significant influence on the carbon budget in floating meadows as compared to forest ecosystems, as shown by larger values of gray relational coefficient (GRC) in GRA. The floating meadows ecosystem (0.82) obtained 54.72% gain in gray relational grades (GRG) value with the forest ecosystem (0.53). This study might help in improving KLNP and other adjutant areas for conservation and management policies from the vital information given on the importance of wetlands in carbon dynamics and ecosystem productivity.

As a part of the Asian Waterbird Census (AWC), surveys on ducks and geese were made at five (5) major waterbird congregation sites of Keibul Lamjao National Park (KLNP) during 2020-2024. A total of 18 species of ducks and two species of geese belonging to the family of Anatidae were recorded during the period. The duck species includes 14 migratory and 4 resident species and the two migratory geese species. Lesser Whistling Duck Dendrocygna javanica was the most abundant and dominant species in terms of population followed by Gadwall Anas strepera and Red - crested Pochard Netta rufina and minimum value was observed in Greylag Goose Anser anser. The Critically Endangered Baer’s Pochard Aythya fuligula was recorded in the year 2023 at Pabot Chingmang site (2 individuals). Another two globally Near threatened (NT) Ferruginous Pochard Aythya nyroca and Falcated Duck Anas falcata have been recorded here.