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Open Access
Impact of climate change on the temporal and spatial distribution of the Indian Peafowl (Pavo cristatus) in Kerala
(Academy of climate change education and research, Vellanikkara, 2016) Sanjo Jose, V; KAU; Nameer, P O
It has been of great importance for the researchers in finding the factors which influenced the species distributions. They are keen to know the current and future distribution patterns of endangered species for implementing the conservation strategies. Some invasive species are expanding their territory into new areas and it have to identify accurately. Avian species are regarded as a good bio-indicator of these devastating changes in the environment. This study was done based on the spatial and temporal distribution of the Indian Peafowl in Kerala, which would be supportive to establish the changes happening in the environment at various places. During the recent decades, rapid expansion in the distribution of the Indian Peafowl was occurred. The hypothesis of this study was that, this expansion is due to the climatic changes. To delineate species distributions and habitat associations, MaxEnt program was used. Using the current presence data acquired from e-Bird data source and 19 bioclimatic variables from WorldClim v1.4 the distribution of the Indian Peafowl had been modelled. Using the current distribution analysis, it would project the distribution of Indian Peafowl into the future by converging it to the maximum entropy probability distribution. Only the uncorrelated variables were used for the study, selected by checking for its percent contribution, permutation importance and R2 value. The study revealed the current (1950-2015) and projected distribution pattern of the Indian Peafowl for the years 2050 and 2070 under different RCP projections. The projected models tells about the increasing spatial distribution of the Indian Peafowl throughout Kerala except in Alappuzha and western slopes of Wayanad. The central part of Kerala is the hotspot of the Indian Peafowl currently and it will be the same in the future. The combined effects of precipitation and temperature variation have an indispensable role in this projected distribution of the Indian Peafowl.
Open Access
Dendroclimatic analysis of teak (Tectona grandis L. f.) from central India to evaluate the potential for climate reconstruction
(Academy of Climate Change Education and Research Vellanikkara, 2016) Reji Mariya, Joy K; KAU; Anoop, E V
Paleoclimatology is the study of climate prior to the instrumental record. Instrumental records are available for a period nearly 100-150 years, which is inadequate for explaining the climate variability and climate change in past millennial time scale. Paleoclimatic data helps in testing the hypothesis about the causes of climate change. When the past climate fluctuations are understood, the climate variations in the future could possibly be anticipated. The science of reconstruction past climate by using tree rings is known as Dendroclimatology. In the present dendroclimatic study, 96 teak core samples have been used from Allapalli (Ggadchiroli, 26 cores), Nagzira (Bhandra, 26 cores) of Maharashtra and Edugurapalli (Bhandrachalam, 18 cores), and Thatibanda (Visakapattanam, 26 cores) of Andhra Pradesh by IITM. Samples were precisely cross dated and ring width was measured using stereo microscope and measurement setup along with the software ‘TROPMET RINGS’, after proper mounting, sanding, polishing and skeleton plotting. COFECHA program was used for checking the quality of corssdating and measurement accuracy. Standardization of the tree ring series is an important aspect of dendroclimatology for removing the non-climate signals from tree ring series and to improve the climate signals. The computer program ARSTAN was used for this specific purpose. Common period statistics produced by ARSTAN show moderately high values of common variance and signal to noise ratio for each chronology, which suggests a high dendroclimatic potential of the chonologies. Climate of site is very important to understood tree-growth climate relationship. Monthly, seasonal and annual climatic conditions over the sampling sites were analyzed by calculating climatology of stations using the data collected from nearby IMD stations. CRU TS (time-series) 3.20 data (0.5-0.5 degree resolution) of monthly gridded temperature and rainfall over a period of 1901-2011 was also used along with IMD data for analyzing the growth climate relationship, since the data showed good correlation with station data. Masulipatnam and Hanamkonda climate is influenced by both Southwest and Northeast monsoon whereas Chandrapur and Nagpur climate is influenced overall warming for all stations. Seasonal rainfall does not have a common trend for all stations. The various response function analyses carried out over study sited in central India clearly indicate the crucial role played by the summer climate in tree growth. All the four cases, for which the relationships between tree growth and climate have been studied, show more or less similar behavior of the growth responses to summer climate (pre-monsoon). The significant negative response of summer temperature associated with the positive response of summer precipitation is mainly related to the availability of moisture which is a function of both temperature and precipitation. The study highlights the importance of moisture availability during beginning of tree growth and the potential of teak for the reconstruction of summer climate.
Open Access
Climate change adaptation through improved water use efficiency in rice (Oryza sativa L.)
(Academy of Climate Change Education and Research Vellanikkara, 2016) Anjaly, C Bose; KAU; Santhoshkumar, A V
The food security of more than half of the world population depends on rice. Studies suggest that global climate change is going to affect the food production through temperature and water stress and this affect the rice production around the globe. The present study tried to elucidate the influence of varying soil moisture status on rice productivity and evaluate the strategies for increased water use efficiency in a climate change adaptation strategy. The study was conducted during May 2016-September 2016 at RARS, Pattambi in variety Jyothi. The treatment combination included the presence or absence of hydrogel along with 4 different levels of irrigation (IW/CPE=2, IW/CPE=1.5, IW/CPE=1 and IW/CPE=0.5). The results showed that the various irrigation levels and hydrogel application had a significant impact on the physiology of rice. Hydrogel application improved the soil moisture availability and increased plant establishment. The maximum plant height was observed for the treatment IW/CPE=2 (105.30 cm) without hydrogel. The hydrogel effect on plant height was significant only up to the booting stage. Hydrogel had its significance on number of tillers only at the vegetative stage of the plant, while, interaction was significant at the vegetative, reproductive and ripening stages. The higher value (19.67) of tiller number was recorded for the treatment IW/CPE=1.5 with hydrogel. LAI was not affected by the application of hydrogel. Only the irrigation treatments had a significant effect on LAI, of which the treatments IW/CPE=2 (2.72) and IW/CPE=1.5 (2.61) recorded the maximum LAI. Higher number of primary branches per panicle was recorded for plants with hydrogel (10.25). The number of panicle per hill was more for the treatment IW/CPE=1.5 without hydrogel (9.20). The number of filled grains produced per panicle is more for plants with hydrogel (86.00). 1000 grain weight observed was higher for the treatment IW/CPE=2 (27.23 g) without hydrogel. Hydrogel did not have any significant effect on the plants physiological parameters like booting, heading, flowering, number of days taken for active tillering and panicle initiation. The more stressed plants took the maximum number of days to booting, heading, flowering and panicle initiation. For the treatment IW/CPE=0.5, there seen no sign of 50 percent flowering and consequently, it did not attained physiological maturity. Hydrogel and irrigation had a significant impact on grain yield. Even though the higher yield (7014.63 kg ha-1) was observed for the irrigation level IW/CPE=2 without hydrogel, the mean average value of grain yield of plants treated with hydrogel is higher than plants treated without hydrogel (4455.03 kg ha-1 and 3951.80 kg ha-1 for with and without hydrogel). It can be concluded that hydrogel had significance only when the irrigation level was low (IW/CPE=1.5 and IW/CPE=1). However, at extreme low water level (IW/CPE=0.5) and high water level (IW/CPE=2), hydrogel failed to exhibit any beneficial role. Under the projected climate scenario using RCP 4.5, it was found for the year 2030 the maximum yield was observed for the treatment IW/CPE=2 (6010 kg ha-1), followed by comparable yield in the treatment IW/CPE=1.5 (5997 kg ha- 1 ). The production was found to be less in the treatment IW/CPE=1 (3504 kg ha-1) and nil to the treatment IW/CPE=0.5. For the year 2050 and 2080, the maximum yield was for the treatment IW/CPE=2.
Open Access
Landslide hazard zonation of Nilambur taluk using remote sensing
(Academy of Climate Change Education and Research Vellanikkara, 2016) Asla, K; KAU; Vishnu, B
Present study aims at the preparation of a landslide hazard zonation map for Nilambur Thaluk of Malappuram district, Kerala and to suggest mitigation measures for controlling landslides. Landslide Hazard zonation is achieved using spatial multi criteria evaluation (SMCE) module of ILWIS 3.31 RS-GIS software. SMCE is based on the Analytical Hierarchical Process (AHP) developed by Saaty (1980). Different parameters contributing to landslides were identified. Thematic maps of various parameters like slope, aspect, soil, geology, landuse, rainfall and elevation were prepared. These thematic layers were standardised and overlaid with appropriate weights to generate landslide hazard zones of Nilambur Taluk. The study area was divided into three zones namely low, medium and high hazard zones. Landslide Hazard Zonation (LHZ) map of the Nilambur Thaluk was prepared using the SMCE module of ILWIS software. According to the LHZ map, 12.4 km2 (0.94%) is located in the low hazard zone, 1080.8 km2 (81.68) % in the medium hazard zone and 230 km2 (17.38%) in high hazard zone. Study found that most of the areas fall under medium hazard zone followed by high hazard zone. Analysis of the LHZ map, revealed that the Western regions of the study area including Akampadam, Kalikavu and Karuvarakundu and areas along the Kozhikode - Nilambur - Gudallur Highway are highly unstable. The probability of occurrence of debris flow in this region is high. These regions have steeply sloping topography and with heavy rainfall during the monsoon season it can cause heavy landmass movement. Some of the tourist spots are concentrated around Akampadam and Karuvarakundu regions like Adyanpara waterfalls and Keralakund waterfalls. Mampad rubber estate, Ariyani rubber estate and areas along Kanjirappuza fall under high hazard zone. Some of the reserved forest area is also coming under high hazard zone. Landslide mitigation measures like slope stabilization, drainage, control of plantations, afforestation, stabilization of roads and avoiding constructional activity in high hazard area have been suggested. The LHZ map was validated by overlaying with previous landslide points.
Open Access
Carbon dynamics in teak planted laterite soils of Kerala
(Academy of Climate Change Education and Research Vellanikkara, 2016) Binsiya, T K; KAU; Kurien, E K
Global warming due to increased concentration of greenhouse gases (GHGs) is one of the important concerns of mankind today. The global soils store about 2500 Gt of carbon which is approximately 3.3 times the atmospheric carbon pool (760 Gt) and 4.5 times than that of the biotic pool (560 Gt) . Kerala has a rich forest cover of which 10 per cent is occupied by forest plantations. Among the plantation species, teak occupies the most prominent position both in acceptance and coverage. However, continuous teak rotation affects the quantity and stability. Hence the present study was taken up to assess the changes in carbon fractions and carbon stability under continuous teak rotations in midland laterites of Kerala. Soils were collected to a depth of 1 m with a depth interval of 20 cm in a chronosequence from 16 plantations at Nilambur, Kerala. Basic soil parameters such as pH, electrical conductivity, bulk density, mean weight diameter, texture, available nitrogen, potassium, phosphorus, iron, calcium, copper, manganese, magnesium, zinc and boron content were analyzed using standard protocols. The carbon fractions were assessed with respect to active, slow, passive and total carbon in soil as well as macro and micro aggregates. The study also assessed the rate kinetics, thermal stability and cumulative CO2 efflux of soil carbon decomposition in these soils by batch incubation experiments at different temperatures. The results showed a reduction of soil basic characters below critical levels with continuous teak rotations. In general, the carbon content was found to decrease depth wise with rotation. However, in plantations without felling organic carbon was found distributed equally in all the layers which may be due to the unhindered transportation and translocation of humic materials with time in these plantations. The carbon stocks in the plantations do not have significant difference between the age groups in their carbon storage capacity. This indicated that carbon losses from the teak plantation are readily replenished and the changes may be expected only in the quality of the stored carbon. Macroaggregates were found to store more organic carbon than the microaggregates. The correlation between carbon and aggregate stability was found to decrease with rotation. Plantation that was grown continuously showed a relatively lower proportion of active carbon than slow and passive carbon fractions. This indicated that even though there was a total carbon increase in plantations under continuous growth, the entire carbon may not be in a labile form to support ecosystem services. Thermal stability studies showed that microaggregates provided better protection to organic carbon by a greater complex mechanism compared to macroaggregates. With temperature, there was an increased conversion of active carbon to passive forms and this conversion could lead to higher carbondioxide evolution once the threshold energy levels were attained. Carbon dioxide efflux studies confirmed these results as higher cumulative CO2 evolution was obtained at 40°C than 25°C in all soils. Further, cumulative CO2 evolution from continuous plantation without felling didn‘t get affected with temperature indicating a dynamic equilibrium with atmosphere. The present study concluded that continuous teak rotation destabilizes carbon in soil and shows the potential to revert to a carbon source than sink if not managed sustainably.
Open Access
Effect of weather on leaf blast incidence in rice and predicting potential epidemics under various climate change scenarios
(Academy of Climate Change Education and Research Vellanikkara, 2016) Aswathi, N R; KAU; Sunil, K M
The rate of global warming is expected to continue increasing if no mitigation efforts take place to reduce the carbon intensity of the world economy and the consequent emission of green-house gases (Raupach et al., 2007). Agricultural production, and thus global food security, is directly affected by global warming (Ainsworth and Ort, 2010). Rice production plays an essential role in feeding the world’s population and will continue to be in the future, because rice is the most important global staple food in many countries. The production of rice, along with other agricultural crops, will be impacted by climate change. There is still great uncertainty about how climatic and atmospheric changes will affect the future productivity of food crops. Major future impacts of climate change are expected on food security and agricultural incomes, including shifts in production areas across the world. In addition to affecting rice production, climate change may alter pathogen dissemination and development rates, and modify the resistance, growth and metabolism of host plants. The geographical distributions of pathogens are very likely to change, and losses can be expected, in part due to altered effectiveness of control strategies. Thus climate change is a serious threat to agriculture because it can lead to significant changes in the occurrence and severity of plant diseases. All phases of the disease cycle, from the germination of spores to the development of lesions, are considerably influenced by climatic factors. The most important climatic factors are temperature and precipitation. These factors may be modified by the coming climate changes. Recent research indicates that the monsoon has changed in two significant ways during the past half-century: it has weakened (less total rainfall during June– September; Ramanathan et al. 2005; Dash et al. 2007), and the distribution of rainfall within the monsoon season has become more extreme (Goswami et al. 2006; Dash et al. 2009). Rice blast caused by Pyricularia oryzae an important disease of rice worldwide is known to cause severe yield losses in rice production area where high inputs of nitrogen fertilizer and favourable climatic conditions occur. Sometimes the yield losses reach as high as 50% in upland cultivations. Objectives of the study were to Study the effect of various weather parameters and climate change on incidence and development of leaf blast disease of rice and evaluation of disease forecasting models for leaf blast of rice. The field experiments were conducted during May 2016 to October 2016 at the Regional Agricultural Research Station of the Kerala Agricultural University at Pattambi, Palakkad district, Kerala. Crops sowing June showed a higher disease incidence compared to other dates of sowing. It was also noticed that variety Kanchana is more susceptible to Leaf blast incidence compared to Jyothi. The effect of weather on LAI significantly varied with varieties. The effect of weather on grain yield was significant. Under upland condition the sheath blight disease incidence was not observed even after artificial inoculation.The effects of weather and varieties on leaf blast incubation period were significant. EPRICE model developed by Savary et al., (2012) was used to forecast the disease severity of leaf blast disease in rice after transplanting. The model works on daily weather parameters particularly rainfall, maximum and minimum temperature, morning and afternoon relative humidity. RMSE for Kanchana prediction is 0.265. This shows that the predicted leaf blast severity was in good agreement with the observed values. So this model can be used for forecasting the rice blast severity under Kerala conditions. The future climatic projections have taken from Ensemble of 17 General Circulation Models (GCMs). The future carbon dioxide concentrations and climate data has been incorporated into disease simulation model-EPIRICE and predicted the future disease incidence possibility of blast for the years 2030, 2050 and 2080 in all the 14 districts of Kerala. The climate data for the years 2030, 2050 and 2080 under different RCPs. The impact of climate change on leaf blast severity in the various districts of Kerala showed a varying trend. Except in the northern districts (Malappuram, Wayanad, Kannur and Kasaragod) the disease severity showed a decreasing trend.
Open Access
Energy use and emission reduction in dairy farm
(Academy of Climate Change Education and Research Vellanikkara, 2016) Athira, P Ratnakaran; KAU; Shaji James, P
Dairy farms use more energy than other agricultural sectors and hence climate change mitigation strategies have a major focus on use of renewable energy along with adoption of energy efficient and environment friendly management methods to improve the profitability of dairy farms. It is widely believed that livestock is contributing largely to the emission pool. The methane emission from enteric fermentation and improper manure management is often the focus of criticism. India being figured fourth in the list of largest emitters, it is imperative that the Indian dairy sector need to be monitored in order to evolve mitigation strategies. Hence this study was intended to investigate the energy use pattern in a medium dairy farm as well as the extent of GHG emission with a view to analyze the economic and environmental advantage of producing renewable energy from anaerobic digestion of cattle dung. The study was conducted at the Permangallur Dairy Farm at Pattambi, Palakkad district. The energy use pattern in different sections of the dairy farm was observed using standard techniques and an energy analysis was done. The total GHG emissions from cattle (enteric fermentation and manure management) were analyzed by using the GLEAM-i model of FAO. In the present study the total average input and output energy were calculated as 37392.3 MJ and 5062 MJ per 1000 L of milk produced. Feed intake had the highest share (97%) from total input energy, followed by electricity (2%). The CH4 emission per cow was found as 322 g/day in the farm. The total CH4 emission from manure management was found to be 41.36 g / head/ day. The total GHG emission from electricity usage in the farm was 87.45 kg CO2 eq /cow/ year. The potential biogas production was 27.8 m3 per day and only 8.6 m3 was used presently. It was inferred that production of electricity with the available balance biogas of 19.2 m3 per day could save electrical energy. Out of the total GHG emission of 3039.7kg CO2 eq /cow/ year it was found that GHG emission can be reduced to 2952.2kg CO2 eq / cow/ year by producing electricity from biogas.
Open Access
Assessment of portable biogas plants for their energy production and emission reduction potential
(Academy of Climate Change Education and Research Vellanikkara, 2016) Iwin, K Augastian; KAU; Shaji James, P
Climate change is one of the serious issues faced currently by humanity. The uncontrolled emission of Green House Gases play a major role in global warming, which eventually leads to climate change. The unscientific methods of waste disposal has serious environmental impacts by continuous emission of GHGs leading to global warming. Households constitute the basic unit in urban energy consumption and waste generation. Anaerobic digestion of the organic fraction of household wastes in a decentralised manner using biogas plants offers great scope in waste management and generation of cheap renewable energy for domestic cooking. The investigations revealed that average amount of organic waste generated per household was 5.28 kg (5 member family) and that of a hostel mess was 24.9 kg (40 inmates). Kitchen wastes in Kerala had a major fraction as liquids and per capita food waste generation in households and hostel mess were 42 g and 153 g, respectively. Average TS of kitchen waste was found as 82 gL-1 and the average pH was found as 3.86. Average C: N ratio of the kitchen waste was found as 53.88:1. The minimum ratio of kitchen waste and inoculum required for a successful start-up of anaerobic system was 1:5. Biogas productivity of kitchen waste was found as 57.57 LL-1and the average specific biogas production from kitchen waste was estimated as 989.05 L kgTS -1. 80-90 % of the potential of kitchen waste to generate biogas can be utilized if the HRT was in range of 40-50 days. Thus it is preferable to have a HRT in the range of 40-50 days for domestic biogas plants working on kitchen wastes. Average methane content in biogas produced from kitchen waste was enumerated as 62.18%. The preliminary biomethanation studies revealed the high potential of kitchen waste to generate biogas. Portable biogas plants are easily shifted and installed, require less space and can be placed conveniently in urban conditions. The four types of portable biogas models used in the study were floating gas holder type (PBP1), floating gas holder type with water seal (PBP2), fixed gas holder type (PBP3) and KAU portable split biogas plant (PBP4). The four portable biogas plants (PBPs) were evaluated by operating them at 50 and 40 day HRT. An increase in mean volumetric biogas production was observed in 40-day HRT compared to 50 day HRT in all PBPs. The maximum increase in biogas production was in PBP4 (34.4 %) and the minimum increase (4.0 %) was in PBP3. This indicated that PBP4 was more suitable for energy production from domestic kitchen waste, which could be operated at a higher gas volume availability at the shorter HRT of 40-day. The maximum value of mean biogas productivity was exhibited by PBP2 at 50-day HRT followed by PBP4 at 40-day HRT. Even though the values were higher at 50-day HRT for all the other three PBPs, the value of PBP4 at 40-day HRT was 11% higher than the mean value for all PBPs at 50-day HRT. Average biogas productivity in all the PBPs during the 40-day and 50-day HRT periods were 53.9 LL-1d-1and 62.25 LL-1d-1, respectively. It was noteworthy that PBP4 had a biogas productivity higher than these average values even at the short HRT of 40 days. The specific biogas production at 40-day HRT in PBP4 was 30 % and 28.5 % higher than that of the average biogas production of all the PBPs at HRTs of 50 and 40 days respectively. Specific biogas production is a true indicator of the energy conversion efficiency of the system and hence the results gave a clear testimony to the superiority of PBP4 over the other PBPs. When the feeding of kitchen waste was interrupted for 12 days, maximum reduction was observed in PBP3 (80.80 %) followed by PBP2 (80.62 %) and the reduction was minimum in PBP1 (72.40%). When the feeding was restarted, PBP4 regained its biogas production faster (7th day) compared to other plants. Average N and K content of slurry from kitchen waste fed biogas plant was found to be 4.025 and 1.315 % respectively, which was notably higher than that from cow dung fed plant. However the P content (0.54) was lower in kitchen waste fed plant. From the study it was inferred that by the use of Portable Biogas Plants (PBP4) total emission reductions of 1263.53 tonnes of CO2e can be achieved per annum for 1000 households in the representative urban area of Kerala.
Open Access
Mulching for soil quality, climate stress mitigation and crop productivity in okra
(Academy of Climate Change Education and Research Vellanikkara, 2016) Anjali Mohan; KAU; Usha, K E
Global warming and climate change is the greatest concern of mankind in 21st century. Under changing climatic scenarios crop failures, reduction in yields, reduction in quality and increasing pest and disease problems are common and they render the vegetable cultivation unprofitable. Various crop management practices such as mulching and the use of shelters and raised beds help to conserve soil moisture, prevent soil degradation, and protect vegetables from heavy rains, high temperatures and flooding. These protective coverings reduce evaporation, moderate the soil temperature and reduce soil run-off and erosion. A study entitled “Mulching for soil quality, climate stress mitigation and crop productivity in okra” was carried out at the Academy of Climate Change Education and Research, Kerala Agricultural University, Vellanikkara, Thrissur during 2015-2016. The experiment consisted of 9 treatments. Mulching with leaf litter, paddy straw, coir pith, black and white embossed sheet, black and silver embossed sheet, newspaper, coir chips, un mulched control and live mulch (cow pea). The biometric and phenological parameters were significantly influenced by the treatments. The plots mulched with plastic sheets showed early germination and higher germination percentage. The highest plant height and maximum number of leaves recorded were in plots mulched with black and silver embossed sheet. Plants mulched with paddy straw flowered earlier (38.33 DAS) and the highest number of flowers (25.66) was recorded in plots mulched with black and silver embossed sheet. In general, mulching with plastic sheets promoted early harvesting and highest crop duration. The highest yield (14.41 t/ha) was observed in plots mulched with black and silver embossed sheet. The soil microbial count was significantly influenced by the treatments. The highest population of bacteria (52.33 × 106cfu g-1) and actinomycetes (171.00 × 105cfu g-1) were observed in plots mulched with paddy straw whereas, the highest population of fungi (22.67 × 104cfu g-1) was observed in plots mulched with leaf litter. With regard to the soil microclimate, the peak value of minimum soil temperature at different depths was recorded in the plots mulched with plastic sheets. The peak value of maximum soil temperature at different depths is observed under plots mulched with black and silver embossed sheet followed by mulching with newspaper. The lowest value of maximum soil temperature at different depth was observed under plots mulched with paddy straw (T2). Higher soil moisture content was recorded under plots mulched with paddy straw throughout the crop period. Plots mulched with coir pith and coir chips also maintained higher moisture content at surface. The results of the present study revealed that mulching has significant influence on soil physical, chemical and biological properties. Mulching with black and silver embossed sheet maintained the soil microclimate which inturn helped to improve the growth and yield of okra.

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