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ThesisItem Open Access Assessment of the Impacts of selected extreme Climatic events on the Marine fisheries along Kerala and Tamil Nadu Coast(Academy of Climate Change Education and Research,Vellanikkara, 2019) Punya, p; KAU; Kripa, VGlobally, one of the most severe impacts of climate change has been identified as the increase in the number of extreme events. The impact of two extreme events, the South India Flood 2015 in Tamil Nadu (TN) and tropical cyclone Ockhi which hit the Kerala and south TN coast in 2017 on the marine fisheries was studied. Analysis of impact on 13 craft-gear combinations in the five flood affected districts of TN indicated that the impact on catch, effort and catch per unit effort (CPUE) varied between districts and gears. Overall, the impact on catch and effort was highly negative in out-board motorised sectors with 64 to 97% reduction. Reduction / absence in pelagic fishes like sardine, Indian mackerel, Stolephorus, and Thryssa was evident and indicating the impact of flood waters in near-shore fishing grounds. Increase in catch of penaeid prawns, lobsters and crabs were observed in some areas indicating disturbance in benthic regions which was beneficial for Mechanized trawlers. The impact of tropical cyclone Ockhi was very high with more than 90% reduction on the marine fisheries of Thiruvananthapuram (TVM), Kollam, Alappuzha and Ernakulam districts. Along TN coast, Kanyakumari, Tuticorin and Thirunelveli were affected and the most impacted was Kanyakumari with more than 85% decline in catch for almost all major gears. The SIMPER test revealed that the species constituting a community were almost the same, but with either low abundance or complete absence. During Ockhi chlorophyll concentration increased by 27% (0.42 to 0.54 mg m-3), the velocity of the surface current increased (0.08 to 0.25 ms-1), SST reduced, there was change in current direction along the Kerala coast. In Kerala, total economic loss from loss in fishing days due to cyclone Ockhi was estimated as ₹107.29 crores with maximum loss at Kollam (₹22.98 crores) followed by TVM (₹16.84 crores). In TN coast, estimated economic loss was 12.5 crores. The study clearly indicated the increased vulnerability of marine fishers and the communities to climate change especially extreme events. The loss in human lives, fishing craft and gear due to Ockhi which was an unexpected event had a deep impact on the coastal communities making the recovery time from impact longer and stressful. The study points out that though the ecological system based changes were low due to tropical cyclone, the socio-economic impact was high and there is a need to develop early warning and vessel tracking systems to increase the preparedness of fishers to unexpected extreme events. Targeted research programs to assess the impact of environmental variations of extreme events on eggs, larvae and juveniles would help to identify the reasons for fishery fluctuations if any and help in fishery predictions.ThesisItem Open Access Growth dynamics and physiological response of selected forestry species to CO2 enriched atmosphere(Academy of Climate Change Education and Research,Vellanikkara, 2019) Anusha, R M; KAU; Nameer, P OTerminalia arjtma, Terminalia bellirica and Terminalia chebula are important medicinal plants and part of Triphala, there is less study about the adaptation and mitigation of these species to elevated CO2. This study is helpful to understand about the adaptive and miligative and biochemical efficiency of these plants. Under elevated these three species are showed a belter response in elevated CO2 SOOppm over ambient 400ppm. The plant height, leaf length and width, stem diameter, number leaves and branches, root length, are higher in elevated SOOppm CO2 over ambient 400ppm as well as the biochemical properties like total chlorophyll and carotenoids, ascorbic acid, protein, proline, total sugar are increased dramatically at SOOppm over 400ppm. The photos>Tithetic rate was higher in elevated CO:in all seasons (winter, spring, and summer), stomatal conductance was higher in SOOppm spring and lower at summer. The intercellular CO2 concentration was higher in plants grown in SOOppm T.chebula in winter in the summer season. Transpiration rate was higher in winter and reduced over ambient in summer. Night respiration is less in T.arjuna compared to ambient, and there is a fluctuation concerning seasonality and species. Carbon sequestration, carbon partitioning, carbon mitigation and carbon stocks are high in elevated CO2 growing plants except for T.bellirica. Organic carbon was higher in elevated CO2 than ambient. Potassium, phosphorous and total nitrogen they with species and change in concentration according to elevated CO2. The plants grown in elevated CO2 are healthier than ambient condition and increases the health-promoting characters. These species are more adaptive and show mitigation efficiency and good biochemical efficiency. In future more studies needed to know about the response of plants towards elevated CO2.ThesisItem Open Access Species richness and carbon stock of Sharngakavu sacred grove, Chengannur Kerala(Academy of Climate Change Education and Research,Vellanikkara, 2019) Kavya Jeevan; KAU; Gopakumar, SGlobal warming and biodiversity loss are the major environmental issues faced by the planet today. The “sacred groves” are repositories of woody vegetation that successfully and efficiently conserve these “trees outside the forests”. Documentation of the species present in such C sinks will help to document the native species that are conserved here. Estimation of carbon locked up in these vegetated areas will help to further understand the potential of these sacred natural sites in mitigating climate change. With this background, a study titled “Species richness and carbon stock of Sharngakavu sacred grove, Chengannur, Kerala” was attempted on Sharngakavu sacred grove, Aalapuzha during 2018- 2019. The objectives of the study were to document the floristic wealth of the grove, enumerate the carbon stock of the grove and to understand the people’s perception on the role of conservation of this sacred grove in combating climate change. The grove was delineated into core zone and buffer zone for detailed vegetation analysis and estimation of carbon stock. Fifty three plant species were recorded from the core zone of the grove, while from the buffer zone, 37 species could be identified. Actinodaphne malabarica and Xanthophyllum arnottianum which is endemic to Western Ghats were observed in the core region. Other species identified, included some major evergreen and semi- evergreen species such as, Aphanamixis polystachya, Ardisia pauciflora, Carallia brachiata, Cinnamomum malabatrum, Cinnamomum verum, Lagerstroemia microcarpa, Morinda citrifolia, Pongamia pinnata and Strebles asper. Some deciduous tree species such as Alangium salvifolium, Grewia tillifolia and Boswellia serrata were also found. The Shannon Weiner index value of the core was about 1.9, which suggests the grove inhabits a fairly good number of species. The core zone was dominated by Xanthophyllum arnottianum while the buffer was dominated by Caryota urens. The carbon stock of the soil was found to be decreasing with depth. The carbon stock of the standing vegetation was found to be the highest in the core which could be attributed to the species richness. The total carbon stock was also found to be the highest in the core zone (456.71 Mg ha-1), while 344.36 Mg ha-1was recorded total C of the buffer zone, even though in terms of area, this constituted the major portion of the grove. Perception studies revealed that majority of the respondents are strongly interested in the conservation of the grove. They also considered deforestation and exploitation of nature as the major causes of climate change. It was also clear that the people’s perception on the causes and impacts of climate change was highly influenced by their age, gender, education and occupation. Among the local residents, people’s interest to conserve the grove was influenced by their age, while among non-resident devotees, education levels was observed to influence their attitude. Traditional beliefs certainly had an influence on the existence of the grove. Even though the grove has been conserved as a part of cultural belief, its role in biodiversity conservation was well understood by the people. Strengthening the people’s knowledge on the importance of value of the grove in both biodiversity conservation and climate change mitigation will help to conserve this Important Plant Area (IPA).ThesisItem Open Access Quantify the temporal carbon, water and energy fluxes in selected land use systems in Himalayas(Academy of Climate Change Education and Research,Vellanikkara, 2019) Arya, M S; KAU; Nameer, P OAn investigation entitled “Quantify the temporal carbon, water and energy fluxes in selected land use system in Himalayas” was conducted at Forest Research Institute (FRI), Dehradun, during 2018 December to May 2019. The experiment was conducted in two seasons winter (December-February) and summer (March-May) with four land use i.e.; mixed forest, pine forest, grassland and bamboo forest. Soil physical properties are also considered at the depth of 015cm and at 15-30cm. The study aimed to give an insight of carbon, water and energy flux variations along micrometeorological observations. The results revealed that during summer season (air temperature increased) all the respective observed fluxes significantly rose, among selected land use. Grassland showed high flux release from the system to the atmosphere. While mixed forest, soil experienced gradual rise in flux exchange, but pine forest system stores greenhouse gases like carbon dioxide in a long time period in a safe manner. Apart from flux, soil temperature and soil moisture were also examined and obtained data showed a decrease in moisture and increase in soil temperature with air temperature rise except leaf shedding months. As the study show that different land use had evident impact on variability in climatic conditions and hence more than considering the green covers, specific land use flux exchange monitoring is required for all terrestrial land use.ThesisItem Open Access Segregating the impact of climate change Vis-A-Vis fishing effort on Inter-Annual variability of selected small Pelagic fishes using numerical models(Academy of Climate Change Education and Research,Vellanikkara, 2019) Pooja, A S; KAU; Grinson GeorgeMarine capture fisheries are subjected to anthropogenic pressures and impact from climate change. These two factors result in the inter-annual variability of marine fish species. In this study, we have tried to nullify the anthropogenic effect in the form of fishing effort by subjecting the fish catch data to a standardization procedure which provided us with the standardized catch per unit effort (SCPUE). The candidate species selected is Indian Oil Sardine which is the dominant and most commercially harvested species. SCPUE of Indian Oil Sardine data and six major climate variables viz., sea surface temperature, precipitation, chlorophyll-a concentration, upwelling, sea-level anomaly and wind speed were subjected to a simulation analysis using regression model with Autoregressive integrated moving average (ARIMA) noise. The lead/lag duration for different climate-related variables used in forecasting the fish biomass was estimated using a Cross-correlation function (CCF) and the model enabled forecast was made for the year 2014 and 2015. The suitable model for the best Akaike Information Criterion (394.13) enabled with a good fit for the output was used for the prediction. On the basis of AIC values and best fit obtained during the study we have arrived at the best combination of variables among the 31 models tested. The variables used in this study was predicted using the approved IPCC models and RCP 4.5 and 6.0 scenarios. Thus we could achieve (i) standardization of fishing effort which segregated the variability in inter-annual fluctuations in Indian Oil Sardine due to effort changes (ii) Scenarios generated for the variables relevant to model studies and predicting them for different RCPs and (iii) Model for forecasting the Indian Oil Sardine biomass using the predicted variables. The study calls upon the need for integrating climatic variables into biomass forecasting with more refined protocols to ascertain the future of Indian marine fisheries in a climate change scenario. Keywords: ARIMA, simulation, climate variables, inter-annual variability, fisheries, Indian Oil sardineThesisItem Open Access Climate envelope modelling of hard corals(Academy of Climate Change Education and Research,Vellanikkara, 2019) Anakha Mohan; KAU; Sreenath, K RThe global climate change is pushing marine ecosystems towards extinction. The sensitive ecosystems like coral reefs will be the first few to take the imminent impacts of an increase in temperature. Unlike any other oceans, Northern Indian Ocean(NIO) is thought to be highly vulnerable due to its typical topography with the massive Eurasian Continent in the north. The Indian Ocean is the warmest among all tropical oceans and more vulnerable in the era of climate change. The ecosystems of this landlocked sea will not permit the migration of the organisms to cooler waters as the years' progress. Scleractinians, the Hard Corals, are sessile and are very sensitive to the shifts in biogeochemical variables. The hard corals in the northern Indian Ocean are increasingly susceptible to elevated anthropogenic stressors, including impacts from climate change, overfishing, runoff, and ocean acidification. In order to study the precise impact of such stressors, the knowledge about the existing extent of hard coral distribution is necessary. The wider distribution and their growth in the oceanic remote islands and ridges makes their complete distribution unknown to science. With the emergence of new powerful statistical techniques and GIS tools, the development of predictive habitat distribution models has become easier. In this study, climate envelope modeling is carried out using maximum entropy principle (MaxEnt) to predict the occurrence of five hard coral species viz., Acropora mitricaUi. Favia pallida. Plaiygyra ckieckilea, Pocillopora damicorms and Porites Itttea by correlating their point observations of data with gridded environmental variables. The statistical model that expresses the correlation and the species threshold to different independent variables is thus employed to create maps of predicted occurrence by applying the model to maps of the environmental parameters. The future distribution of each species was delineated using the IPCC emission scenarios, RCP 4.5, RCP 6.0, and RCP 8.5 for the period of 2040-50 and 2090-2100. The study unveils possible distribution areas of these hard-coral species' in the northern Indian Ocean and their vulnerability towards elevated greenhouse gas emissions in the future decades. Much of future estimates of occurrences, all these corals are noted in new areas that are now devoid of coral reefs mainly the entire Indian coast and the east African coast. A. muricuta is found to be most vulnerable species under all the three RCPs. It is also found that the Red Sea, Persian Gulf and Indian coasts are found to be more exposed to the vagaries of climate change regarding coral distribution. Tlie nature of the relationship of coral distribution with the climatic parameters as predicted by this study can also help conservators and marine protected tnea managers well prepared for expected but sudden environmental changes. Prediction of future shifts in the hard-coral occurrence will provide a guideline to the management actions either to decrease the impact or prevent possible extinction events.ThesisItem Open Access Carbon sequestration and crop weather relations in long term fertilizer experiments(Academy of Climete Change Education and Research, Vellanikkara, 2018) Sudhamani, P; KAU; Thulasi, VThe present study entitled “Carbon sequestration and crop weather relations in long term fertilizer experiment was formulated with the objectives of studying the effect of long term application of fertilizers and manures on soil carbon sequestration pattern and crop weather relations under long term fertilizer experiments with rice-rice cropping sequence maintained at Pattambi. The objectives were set out to study the carbon sequestration pattern in long term fertilizer experiment (LTFE), estimation of the SOC sequestration efficiency of different organic manures and to analyze and establish crop weather relations in LTFE. The LTFE consist of 12 treatments viz. T1:50 percent NPK, T2: 100 per cent NPK, T3:150 per cent NPK, T4: 100 per cent NPK + lime CaCO3 @ 600 kg ha-1, T5: 100 per cent NPK, T6: 100 per cent NP, T7: 100 per cent N, T8: 100 percent NPK + FYM @ 5 t ha-1 (to Virippu crop only), T9: 50 percent NPK + FYM @ 5 t ha -1 (to Virippu crop only), T10: 100 percent NPK + in situ growing of Sesbania aculeata (for Virippu crop only) ,T11: 50 percent NPK + in situ growing of Sesbania aculeata (for Virippu crop only), T12: Absolute control (No fertilizers/ manures). The grain yield, straw yield, stubbles left after harvest and unincorporated weed biomass were quantified for calculating the carbon inputs into soil. The soil organic carbon distribution pattern was analysed in different depths. The total carbon inputs and soil organic carbon sequestration rate were plotted to establish the relationship. Crop weather relations were studied through correlation studies and DSSAT modelling. Integrated nutrient management practice T8 (100 Per cent NPK + FYM) recorded higher values for grain yield and growth related parameters followed by T10 (100 per cent NPK + in situ growing of Sesbania aculeata) and T3 (150 per cent NPK).The soil which received 100 per cent NPK+FYM (T8) had higher mass of total organic carbon in top soil followed by T10. A significant positive linear relationship exists between carbon inputs and rate of carbon sequestration. The mean carbon sequestration efficiency was 8.4% in top soil. The average sequestration efficiency for FYM and daincha were 12.18 and 8.58% respectively. The decrease in dose of fertilizers incorporated along with organic manures decreased the carbon sequestration efficiency of the organic amendments. Therefore application of FYM seems to be a preferred strategy for enhancing SOC sequestration in lateritic soils due to its higher carbon sequestration efficiency. Maximum temperature had a positive impact on grain yield in both seasons Virippu and Mundakan, while the effect of minimum temperature was not significant. In general the rainfall and wind speed had negative impact on grain yield. Furthermore, crop weather relations in rice are established by using available long term data using DSSAT. There is perfect concurrence between observed and predicted grain yield of the experiment. So this study will help in planning better and judicious carbon management strategies and recommendations for these soils for sustainable health and crop production.ThesisItem Open Access Modeling rice production in kole lands and its vulnerability to climate change(Academy of Climate Change Education and Research Vellanikkara, 2018) Surabhi, S R; KAU; Sandeep, SRice is the most important staple food crop for more than 2/3rd of India’s population, and is the primary source of food for more than three billion people globally. Hence rice production plays a significant role in food security under a changing climate. The Kole lands is a multiple use wetland ecosystem covering an area of 13,632 ha spread over Thrissur and Malappuram districts, and form one of the rice granaries of Kerala. It is a part of the unique Vembanad-Kole wetland ecosystem. The objectives of the study were to develop crop weather relationship for the predominant rice varieties and assess possible changes in yield due to climate change and to study the impact of abiotic factors and farming practices on rice production using simulation model. Daily weather data for the period 1998-2016 were collected from the India Meteorological Department, Thiruvananthapuram. Information on area, production and productivity of rice in Kole lands was collected from Agriculture Statistics Report - Department of Economics and Statistics, Kerala. The weather data from General Circulation Models based on RCP 4.5 and 8.5 were used for the analysis and projections were made up to 2050. Weather cock v.1.5 was used for converting the daily weather data into standard week, month and seasonal formats. The rainfall parameters or indices like seasonal and monthly rainfall, rainy days and high rainfall events were calculated. It is also used to compute PET and Thornthwaite water balances. The crop simulation model DSSAT –developed by IBSNAT was used for studying the impact of climate change on these ecosystems. The monthly rainfall of Kole lands indicates that there was an increase in rainfall during the months of June, July and August as per RCP 4.5 and 8.5. According to RCP 4.5 and 8.5 an increasing trend in number of seasonal rainy days was observed during the monsoon seasons. The maximum amount of potential evapotranspiration was observed during the month of May, whereas the minimum in, November December, and January. The months of January, February, March, April, November and December were found to have no surplus. Whereas water deficit is projected to happen during the month of march. The maximum amount of surplus was found to occur in July and the yearly value shows an increase from the current condition. The area under rice production has shown a declining in Kole lands over a period of 2008 – 2017. Results indicates that the productivity of rice in Kole lands during the first cropping season was 2.08 t/ha. By 2030, the second cropping season was projected to have a yield of 3.124 t/ha. By 2050, the third cropping season would surpass the productivity of first two seasons with productivity of 3.424 t/ha.ThesisItem Open Access Impact of climate change on the temporal and spatial distribution of the selected migratory bird species in Kerala(Academy of Climate Change Education and Research Vellanikkara, 2018) Induja, B; KAU; Nameer, P OGlobal warming and climate change are terms for the observed century scale rise in the average temperature of the earth’s climate system and its related effects. The climate change prior to industrial revolution can be explained by natural phenomena. Anthropogenic climate change has a significant role on physical and biological systems all over the globe. The multiple components of climate change are anticipated to affect all the levels of biodiversity, from organism to biome levels. Researches have been done in identifying the factors affecting species distribution and analysing their current and future distribution pattern. Species are affected in a different manner, many are forced to migrate at different rates through fragmented landscapes. The migration of animals and birds is linked to climate factors such as temperature, moisture availability and amount of daylight. These migrations can be considered as a biological indicator of climate change as these species are expected to track the shifting climate. Avian species are one of the best bioindicators and many migrating birds are very sensitive to environmental changes and are already being affected by climate change. Increasing temperatures, changing vegetation and extreme weather conditions lead to significant changes of the birds’ essential habitats. The present study is a supporting element for the above statements. The spatial and temporal distribution of selected migratory species was studied in identifying the changing climate. Certain dry land inhabiting bird species such as Bunting species (Black-headed Bunting), Lapwing species (Gray-headed Lapwing), Wheatear species (Isabelline Wheatear), Bluethroat, Aquila species (Greater-spotted Eagle) and Stonechat species (Common Stonechat) are selected for the study. Recently the Kerala state has been witnessing the increased number in the arrival of certain migratory birds usually inhabiting the drier tracts of warmer countries.It is hypothesised in the study that the increased distribution of these birds could be an indication that the climate in Kerala is changing. For analysing the species distribution, Maxent model was used. Using the current bird data collected from e-bird database and the climate data acquired from the WorldClim v1.4 database, the modelling for the present condition was done. Then utilising the current distribution analysis, it would project the distribution of the bird species into the future by converging it to the maximum entropy probability distribution. The study revealed the current (1950-2015) and projected distribution pattern of the selected migratory bird species for the years 2050 and 2070 under different RCP projections. The current distribution pattern says that the presence of Black-headed Buntingis observed at the northern and southern tips of Kerala, the Bluethroat at the central region, the Grey-headed Lapwing and the Common Stonechat towards the central and southern portions, the Greaterspotted Eagle at the central and southern regions and the Isabelline Wheatear towards the southern regions. The projected modelling results reveal that the distribution of the selected migratory bird species would be expanding more to the entire plains of the Kerala state excepting majority of the high land regions. For the current and future distribution of the given bird species the effect of temperature is more important comparing to precipitation effects.
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