1. KAUTIR (Kerala Agricultural University Theses Information and Retrieval)
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Item Technology assessment and refinement in coastal homegardens of Kerala: linkages with biodiversity and household livelihoods(Department of Agricultural Extension Education, College of Agriculture , Vellayani, 2024-01-15) Roshni Thampi; KAU; Allan Thomas; Joy, MThe study entitled “Technology assessment and refinement in coastal homegardens of Kerala: Linkages with biodiversity and household livelihood” conducted from 2019 to 2023 focused on the primary objectives to assess crop diversity, identify the dominance of crops, delineate technology needs, sorter dimensions of technologies and analyze the adoption and technology gaps through action research for sustainable coastal home garden systems. The study also examined the social anthropogenic variables of coastal home garden farmers and explored the linkages between biodiversity and household livelihoods in terms of perceptions and practices by farmers. Constraints in the coastal home garden farming system as perceived by farmers and extension personnel were also studied. The study was conducted in homegardens of three coastal Agro Ecological Units (AEU 1- Southern coastal plains, AEU 3- Onattukara Sandy Plains and AEU 4- Kuttanad) of southern Kerala. 35 farmer respondents were chosen from the home gardens of selected panchayats, comprising 15 participants and 20 non-participants who had at least 25 cents. The total numbers of respondents for the study were 165 comprising 105 coastal home garden farmers, 30 Agricultural Officers and 30 Scientists. Within the framework of Participatory Technology Assessment and Refinement, a collaborative effort was made to select appropriate technology for the primary crops within specific AEUs. This encompassed the evaluation of technology for bittergourd in AEU 1, chilli in AEU 3, and cowpea in AEU 4. Furthermore, Front Line Demonstrations (FLDs) were conducted to showcase and validate KAU-proven technologies that were deemed suitable for these specific crops. The structural configuration in terms of dominance-biodiversity profile of crops in coastal home gardens of southern Kerala was studied under two aspects viz., numerical and economic dominance and the diversity profile of coastal homegardens in Kerala. The study revealed that in AEU 1, out of the 82 identified crops, the most dominant one was coconut (5.90) followed by bittergourd (5.81) whereas in AEU 3 a total of 78 crops were identified, of which the maximum dominance was noted with black pepper (5.65) followed by chilli (5.26). In AEU 4 a total of 85 crops were identified of which the maximum dominance was noted with cowpea (5.24). The study compared the mean diversity index across different AEUs and found that AEU 4 exhibited the highest diversity index at 1.547, followed by AEU 3 at 1.159, and AEU 1 at 1.058. When examining the crop-wise diversity profile of coastal AEUs, fruits had the highest diversity index at 0.998, followed by vegetables at 0.878, and spice crops at 0.850. Conversely, the lowest biodiversity index was recorded for tubers at 0.360 and ornamental plants at 0.357. In AEU 1, the maximum diversity index was observed for spices at 0.801, followed by vegetables at 0.770, and medicinal crops at 0.741, with tubers having the lowest diversity index at 0.350. In AEU 3 and AEU 4, the highest diversity index was noted for fruit crops at 1.181 and 1.164, respectively, while the lowest diversity index was recorded for medicinal plants at 0.225 and 0.226 respectively. One-way ANOVA analysis revealed no significant difference in crop diversity among selected AEUs, but there was a significant difference in crop-wise diversity for plantation crops, multipurpose trees, medicinal plants, tubers, and ornamental plants. In terms of region-wise biodiversity, the mid-regions had the highest diversity index at 1.433, while the courtyard of coastal home gardens had the lowest diversity at 1.117. The study on vertical diversification of crops in different coastal AEUs revealed that in AEU 1 maximum diversification was seen for banana with six levels of diversification whereas in AEU 3 maximum diversification was seen for banana and coconut with five levels of diversification. In AEU 4 the maximum diversification was seen for coconut and banana with four levels followed by cowpea and black pepper with two levels of diversification. The extent of horizontal diversification was also recorded and found that 40 % of the homegardens in AEU 1 had 5 tier diversification whereas in AEU 3, 60 % of the home gardens had 6 tier or more diversification. In case of AEU 4, 73.33% of the homegardens were having 6 and more tiers of diversification. The study revealed that a significant percentage (53.33%) of homegardens in all AEUs had six or more tiers of diversification. This study involved assessing the technology requirements for the top dominant crops in the selected AEUs. The study identified that in AEU 1, the maximum technology need was recorded with production practices of bittergourd (6.83), whereas in AEU 3, the highest technology need was noted with protection practices (leaf curl disease management) in chilli (6.67). In AEU 4, highest technology need was noted for production practices in cowpea (6.50). Based upon the technology needs of the dominant crops in different AEUs, FLDs were conducted in selected three homegardens on production aspects of bittergourd (AEU 1) and cowpea (AEU 4) and protection aspects for chilly (AEU 3). The FLD in all the AEUs of study clearly highlights that scientific approach in farming and correct use of technology in accordance to KAU POP will help the farmer to derive more profit through improved production. The B:C ratio for FLD studies on bittergourd cowpea was found to be higher (1.96 and 1.78) compared to farmers practices (1.37 and 1.42). Research showed that using scientific methods like KAU practices reduced leaf curl disease in chilli by 48.19%, emphasizing the importance of adopting these techniques. The study also examined how farmers adopted KAU practices. It was found that 77.14% of AEU 1 farmers had low adoption, while 74.29% of AEU 4 farmers had high adoption. In AEU 3, 51.43% had low adoption. The study also categorized farmers as innovators (0.95%), early adopters (16.19%), early majority (34.29%), late majority (32.38%), and laggards (16.19%). In the study, a reliable scale was developed to assess technology-related aspects in Kerala's coastal home gardens. The Single ANOVA tool helped choose indicators with a mean value below 4.49, resulting in 26 variables across 8 dimensions. For reliability, the odd-even split-half method was used, yielding a strong correlation of 0.846 for the half-test and 0.917 for the full test. Pearson's correlation coefficients also confirmed the scale's validity by exceeding 0.25 at a 0.05 significance level. The scale was administered to respondents and the results showed that participating farmers perceived economic dimensions (4.62), environmental dimensions (4.30), and psychological dimensions (4.31) as the most important. Non-participating farmers, on the other hand, considered economic dimensions (4.61), psychological dimensions (4.14), and human resource dimensions (4.12) to be significant. Extension personnel, in their evaluation, rated economic dimensions (4.28), human resource dimensions (4.04), and political dimensions (4.03) as the most important factors. Cluster analysis was done for different dimensions for different categories of respondents and it invariably shows interaction effects of different dimensions of technology. The analysis was done using Ward linkage with 26 indicators, representing 8 dimensions of technology in coastal homegardens. For participant farmers 3 clusters were identified. The first cluster comprised of 10 indicators viz., profit, sustainability, technical efficiency, interpersonal relationship, initial cost, bureaucratic support, perception of technology, coordination, supply chain and acquisition of information that showed strong association. The second cluster encompassed 12 indicators that demonstrated proficiency in areas such as credit access, effective decision-making, keen observability, viability, adept resource management, resource recycling capacity, reasonable price expectations, local resource utilization, ready availability, utilization of family labour, dependable delivery reliability, and skilled labour requirements. The third cluster, comprised of four dimensions, exhibited characteristics related to flexibility, strong social networking, effective budgeting abilities, and openness to utilizing open-source technology. Analysis of livelihood assets revealed that social assets scored the highest mean value (239.3) followed by human assets (227.3), physical assets (185.6), natural assets (172.3) and financial assets (176). ANOVA confirmed that there is significant difference between AEUs in case of all assets except human assets and Pearson correlation analysis was conducted to examine the strength and significance of the relationship between these variables. The results showed a moderate positive correlation (r = 0.311, p < 0.05) between total assets and biodiversity. This suggests that as the total assets of the communities increase, the level of biodiversity also tends to increase. The study delved into gender roles within various coastal home gardens, with a focus on dominant crops. In AEU 1, particularly in bittergourd cultivation, men were predominantly engaged in labour-intensive tasks like land preparation (54.29%) and drain preparation (85.71%). Women, conversely, played more active roles in activities such as weeding (51.43%), kitchen gardening (57.14%), and harvesting (51.43%). Both genders actively participated in operations like irrigation (62.86%), plant protection activities (57.14%), and post-harvest tasks (51.43%). In AEU 3, where chilli cultivation was highlighted, men took on tasks like drain preparation (62.86%) and fencing (74.29%), while women were prominently involved in sowing seeds (68.57%), planting seedlings (57.14%), plant protection (57.14%), kitchen gardening (54.29%), harvesting (74.29%), and post-harvest operations (62.86%). Both men and women contributed to activities like applying manure (62.86%) and fertilizers, as well as weeding (54.29%). In AEU 4, centered on cowpea cultivation, men primarily handled land preparation (60%). Interestingly, women took on most responsibilities related to cowpea cultivation including, applying manure (57.14%), sowing seeds (51.43%), planting seedlings (51.43%), applying fertilizer (57.14%), weeding (51.43%), kitchen gardening (57.14%), and harvesting (60%). Both genders were involved in applying irrigation (54.29%). A chi-square test assessed the significance of gender differences in home garden activities, revealing a strong association between gender and agricultural tasks. The calculated chi-square statistic was 192.78, surpassing the table value of 33.92 at a 0.05% significance level, affirming the substantial gender differences in home garden activities. The study identified a total of 22 constraints within coastal home gardens, which were rated by respondents. The most significant challenges reported by coastal home garden farmers were, lack of scientific knowledge (1031) followed by salinity issues (rated at 1010), flooding concerns (1008), ineffectiveness of plant protection methods at recommended dosages (rated at 969), insufficient knowledge about plant protection chemicals (960), the impact of climate change (948), and the absence of proper drainage systems (916), listed in descending order of importance. Key suggestions to improve coastal home gardens as perceived by farmers and extension personnel were, the creation of customized packages of practices tailored to the coastal home garden system, enhanced on-going support and guidance from extension agencies for the adoption of recommended scientific practices and the promotion of Farmer Producer Organizations (FPOs) to enhance post-harvest handling and marketing Social anthropogenic variables of coastal home garden farmers like age, education, gender, occupation, economic motivation, extension contribution, irrigation potential, information source utilization, credit orientation, training need, market orientation and adoption were also studied. In essence, the research revealed a multifaceted profile of dominance and diversity within the coastal home garden community. Furthermore, it outlined specific technology requirements, adoption patterns, and dimensions conducive to the development of coastal home gardens. Additionally, the study delved into aspects related to livelihood assets, gender roles, constraints, and provided valuable suggestions to promote the sustainability of coastal home gardens in the Kerala region.Item Species richness and carbon stock of Sharngakavu sacred grove, Chengannur Kerala(Academy of Climate Change Education and Research,Vellanikkara, 2019) Kavya Jeevan; 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).Item Identification of the population genetic structure of Carcharhinus longimanus (oceanic white tip shark or brown Milbert's shark) using mitochondrial DNA markers(Department of Plant Biotechnology, College of Agriculture, Vellayani, 2019) Sreelekshmi, S; Sandhya SukumaranEven though sharks are the largest fishes in the world with their size varying size and behaviour, they were over exploited and most of them were at the fear of extinction. Among these Carcharhinus longimanus, an epipelagic bottomless shark considered as at the point of extinction were IUCN Red list points out this shark as a “vulnerable” species at global level. In order to implement the management measures for these species which require the information regarding its population in interoceanic regions. Population genetics can be characterized as the study of how hereditary variance is dispersed among the species and population on a very basic level (Hansen, 2003). Assessment of genetic makeup and variability of fish stock is important for scientific management of fishery, conservation and rejuvenation of endangered species. Mitochondrial DNA (mtDNA), which in general possess a five to ten times greater variability than single copy nuclear genes hence, served as a powerful tool for elucidating population structures studies. Among the 150 specimens of C. longimanus sequenced, we obtained sequences ranging from 720 base pairs were obtained 12 polymorphic sites yielding 13 haplotypes. Genetic differentiation among the populations of C. longimanus from Indian Ocean was revealed as a non-significant statistical analysis. Vital insights were gained from this study indicating lack of significant substructuring and its capability to migrate across large expanses of Open Ocean. The capability to migrate may provide it with some buffering against habitat loss and climate change, but excessive fishing is a danger to its populations. Globally sharks are in danger due to their inherent vulnerabilities like long gestation time and reduced number of offsprings coupled with over fishing. Our study also corroborated the findings of shark decline, as decline in genetic diversity is an indicator of decrease in resilience capacity. The present study calls for restrictions on its fishery so that populations will get sufficient time to replenish and consequently their resilience is ensured in the face of changing oceans.Item Impact of invasive alien Plants on understorey vegetation in Tholpetty range of Wayanad Wildlife Sanctuary(Department of Natural Resource Management, College of Forestry, Vellanikkara, 2019) Harilal, K; Gopakumar, SA study titled “Impact of invasive alien plants (IAP) on understorey vegetation in Tholpetty Range of Wayanad Wildlife Sanctuary” was undertaken to understand the distribution characteristics of selected invasive alien plant species (IAPS) viz., Lantana camara L., Senna spectabilis (DC.) H.S. Irwin and R.C. Barneby and Chromolaena odorata (L.) R.M. King & H. Robin in the three vegetation types (Plantation, NF, and Vayal) of WS I part of the WWLS. The additional objective was to assess the impact of these IAPS on the native plant communities in these vegetation types. In the WS I area, L. camara invasion was rampant, except in the southern regions. Higher invasion was seen in the Kaimaram and Thirulkunnu forest sections. C. odorata invaded all the four sections viz. Kaimaram, Dasanghatta, Thirulkunnu and Bavali. S. spectabilis invasion was heavy in the Kaimaram section near the boundary of Thirunelli RF, and in the boundaries between Nagarhole TR and Kaimaram section. In all the three vegetation types, the density of Chromolaena was high, while it was lowest for Senna. The density of Chromolaena in NF, Plantation and Vayal was respectively 3734.11 ± 5.65, 8457.64 ± 27.52 and 7761.17 ± 9.74 stems/ha. The density of Lantana in NF, plantation and Vayal was respectively 1061.17 ± 2.75,334.11 ± 1.02and 215.29 ± 0.50stems/ha. The density of Senna in NF, plantation and Vayal was 414.11 ± 1.55, 589 ± 2.67 and 34.11 ± 0.21stems/ha respectively. In the Vayals, Senna invasion, though minimal, could be noticed. Chromolaena had the highest percentage cover in both plantation (24.58 ± 3.06) and Vayal (46.19 ± 4.03). In NF, Lantana (19.46± 3.43) had the highest percentage cover. In all the three vegetation types, Chromolaena had the highest frequency and abundance. Out of the total 140 plant species identified from the WS I region, number of species recorded in each weed category types like L, C, S, LC, CS, LS, LCS and Control were 67, 96, 20, 64, 9, 7, 14 and 113 respectively. Vis-a-vis the impacts of IAPS in NF, highest MSR (Mean Species Richness) was seen in Control (weed-free area), followed by L (Lantana invaded) and C (Chromolaena invaded) regions. The lowest MSR was in LCS (Lantana, Chromolaena, and Senna invaded) and LS (Lantana and Senna invaded) regions. In plantation, highest MSR was seen in Control (weed-free area) and the lowest in L (Lantana invaded) area. In Vayal too, highest MSR was observed in control, followed by C (Chromolaena invaded) and lowest in LC (Lantana and Chromolaena invaded) areas. All three IAPS negatively influenced the native species richness, although no specific declining trend in species richness could be observed. Among the three IAPS, C. odorata had the biggest impact on the species richness of native species in both NF and Vayal. In the plantations, L.camara had the biggest impact on species richness. Canopy openness and percentage cover of IAPS were found to be positively correlated. In NF and Vayal, Lantana showed highest correlation with canopy openness, while in plantation, Chromolaena showed highest correlation with canopy openness. In plots where Senna and Lantana occurred together, plant species richness decreased from 67 to 7. Similarly, when Senna and Chromolaena came together, species richness dropped from 96 to 9. This probably indicates a dominating interference of Senna on the recruitment of native species which needs research attention. Left unmanaged, Senna will soon become a major “biological pollutant” of Wayanad WLS.Item 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; 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.Item Evaluation of fragrant vandaceous orchids for ornamental traits(Department of Floriculture and Landscaping, College of Horticulture, Vellanikkara, 2017) Deepa, T; Geetha, C KTwenty five fragrant vandaceous orchids were evaluated in the Department of Floriculture and Landscaping during the period from June 2016 to May 2017 with the objective of classifying them based on aesthetic and economic parameters for commercial exploitation as value added plants. The varieties exhibited wide variation in both vegetative and floral characters. Considering quantitative characters, Vasco Crownfox Red Gem recorded the maximum plant height (68.73cm), spread (52.23cm), internodal length (1.95cm) and leaf length (33.83cm). V. Pranerm Prai x V. tessellata showed maximum shoot girth (4.99cm), leaf area (105.54cm2), leaf number (37) and root length (181.75cm). The least values for all these characters were for Neostylis Lou Sneary. Duration from spike emergence to opening of florets was the maximum in Ascda Peggy Foo x Rhyn. Coelestis Blue and minimum in Neostylis Lou Sneary. Maximum spike longevity was recorded in V. Rothschildiana (29.30 days) whereas it was minimum in Rhy Sri Siam x Rhy gigantia (7.50 days). Interval of spike production was also the longest in Ascda. Peggy Foo x Rhyn. coelestis Blue and the minimum in Rhynchorides Bangkok Sunset. Spike production was the maximum in Neostylis Lou Sneary, followed by Ascda Srichai and Vasco Crownfox Red Gem. The varieties/ hybrids varied with regard to blooming period. The peak flowering was from May to July. Longer spike and rachis were noticed in Aerides quinque Vulnera Rhy. Coelestis. Vasco Blue Bay Pink had the highest number of florets/ spike and the shortest internodal length. Largest flowers were observed in V. Rothschildiana. Petal and labellum of the varieties also exhibited different colour patterns such as uniform, spotted, netted, tessellated and shaded. All the evaluated varieties were fragrant and were categorized based on different notes such as floral, fruity, spicy, green, sweet and miscellaneous. Fragrance was very faint in V. Rothschildiana whereas it was musty in Darwineria Cream Puff. With respect to the post-harvest characters longevity (vase life) was the maximum in V. JVB X Ascda Yip Sum Wah (17.30 days) and individual floret life (8.13 days) in V. Rothschildiana. Colour and pigmentation, texture, shape, pattern and size of florets as well as arrangement of florets on the spike were considered for the visual evaluation of a variety for use as cut flower. Considering the overall qualitative and quantitative attributes, Vascostylis Crownfox Red Gem, Vasco Blue Bay Blue, Rhynchorides Bangkok Sunset, V. Mimi Palmer, V. JVB X Ascda Yip Sum Wah and Vasco Blue Bay Pink were excellent for cut flower production. Plant quality evaluation was done based on fullness, growth and visual appearance, flower colour and pigmentation, spike longevity, shape and arrangement of foliage during the growth period. Fragrance scoring was also done based on intensity and diffusiveness, newness and beautifulness of fragrance. Based on the flowering phenology, four phenophases, namely, November – January, February – April, May – July and August – September were recorded and the varieties were categorized accordingly. Side-runs with different colour combinations were observed within a phenophase. The varieties were also categorized on the basis of flower colour, number of florets/ spike and floret size, longevity of spike on the plant , number of spikes produced / year and fragrance. Considering overall quantitative and qualitative characteristics, the evaluated varieties/ hybrids were categorized for cut flower, indoor and outdoor gardens for commercial exploitation as value added plants. The fragrance also makes it a novelty in landscaping to create a peaceful, relaxing environment.Item Evalulation of soil and water quality in potta watershed of pazhayannur block in Thrissur district(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2017) Raghunath, H N; Betty BastinAn investigation entitled ‘Evaluation of soil and water quality in Potta watershed of Pazhayannur Block in Thrissur district” was undertaken in the department of Soil Science and Agricultural Chemistry, College of Horticulture, Kerala Agricultural University during the Year 2016-17. An intial survey was carried out in the different reaches of the watershed to identify the water resources, crops. Vegetation, manures, fertilizers and pesticides used. Based on the data generated, thirty Soil samples were samples were collected from each reach. Soil samples were collected only during the pre-monsoon season (April to May, 2016) and post-monsoon November to December, 2016) season. The soil samples were characterized for texture, bulk density, particle density, water holding capacity (WHC), pH, electrical conductivity (EC), organic carbon (OC), cation exchange capacity (CEC), available nutrients (N, P, K, Ca, Mg, S, Fe, Mn, Zn, and Cu) and heavy metals (Pb, Ni, Cr, and Cd) and heavy metals (Pb,Ni,Cr and Cd). Water samples were analyzed for chemical properties like pH, EC, TSS, cations, (Na+ , Ca2+ , K+, Mg2+) anions (CI-1, SO42-, CO32-, HCO3- and NO3- )heavy metals Cd, Pb, Cr, and Ni). The texture of soils in all the three reaches were found to be sandy loam. Soils from all the reaches were acidic and the pH varied from 3.47 to 6.80 with very low electrical conductivity(0.021 to 0.170 dS m-1). Cation exchange capacity of the soil samples varied between 4.15 to 8.97 c mol (p+) Kg-1. in the soil samples of upper reach was deficient in soil OC. Deficiency of available N in all reaches and that of P in upper and lower reaches was observed. The highest deficiency of K was noticed in the soil samples of upper reach. All the reaches were deficient in secondary nutrients (Ca and Mg). The available heavy metals in the soil was found to be below toxic level and their contents decreased in the order of Pb > Ni > Cr > Cd. Micronutrients (Fe, Mn, Zn and Cu) were found to be sufficient and their contents followed the order Mn > Fe>Cu > Zn Significant differences were observed between upper and middle reached in the content of soil available N, P and K. The association of soil properties showed that the soil organic carbon (SOC) was significantly and positively correlated with soil water holding capacity and available nitrogen in all the reaches, whereas it was negatively correlated with the bulk density of soil. During both pre and post – monsoon periods, PH of the water samples ranged between acidic to neutral values (5.62 to 7.47). electrical conductivity of water samples ranged from 0.14 to 0.54 dS m-1 . The content of cations, viz.,Ca and Mg were high in post-monsoon season while Na and K were high in pre-monsoon season. Analysis of anionic composition of water samples showed that the content of anions viz., bicarbonates, chlorides and nitrates were higher in post monsoon compared to pre-monsoon. The heavy metals like lead, chromium and cadmium were found to be below detectable level in all the water samples collected during both pre and post –monsoon seasons. Water samples registered significant differences in the contents of Ca, Mg, HCO3- between pre and post –monsoon seasons . The quality of water from all the reaches can be rated as good and suitable for irrigation. Further studies can be focused on the assessment of the impact of different soil conservation measures on the soil health. Soil test based fertilizer recommendations including various organic resources have to be adopted by the farmers.