ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat ... more ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat straw (WS), potato plant (PP), and mustard stover (MS) were prepared with or without fish pond bottom sediment to investigate the compost maturity and their suitability for field application. The composting process was monitored through the changes in physico‐chemical parameters and germination index (GI) at every 7 days interval of the composting process. All the composts were dark brown and smelled like forest soil within 56 days of composting, which reflected its matured status. On the basis of the physico‐chemical parameters (bulk density: 0.84 g/cm3; pH 7.05; electrical conductivity: 3.52 mS/cm; cation exchange capacity:82.4 cmol/kg; total carbon:321.4 g/kg; total nitrogen: 16.9 g/kg; As: 6.8 mg/kg; Cd: 2.96 mg/kg; Cr: 29.6 mg/kg, Cu: 243.6 mg/kg; Hg: 0.019 mg/kg; Ni: 24.3 mg/kg; Pb: 62.1 mg/kg and Zn: 812 mg/kg) and GI (89–96%), it could be concluded that RS/WS/PP/MS, 1:1:2:1 v/v/v/v with fish pond sediment produced better compost in accordance with the Indian compost standard. Application of a combined randomized block design analysis revealed that there is a significant difference in the responses of the five composts, in relation to the time of composting. Hierarchical clustering algorithm was applied with a view to form homogeneous groups of five different composts on the basis of different physico‐chemical parameters. Therefore, the ratio of waste incorporation is an important decision for composting and addition of pond sediment can improve the quality of compost.
Additional file 1: Table S1. Distribution and density (no. of individuals ha-1) of vegetation acr... more Additional file 1: Table S1. Distribution and density (no. of individuals ha-1) of vegetation across various sampling stations of the wetland and Kruskal-Wallis test with habitat conditions under different sampling stations as the main effect variable; Table S2. One-way analyses of variance for micro-topography, water flow regime and vegetation attributes in the wetland with flood phases as the main effect variable; Table S3. Importance Value Index (IVI) of vegetation across various sampling stations of the wetland and Kruskal-Wallis test with habitat conditions under different sampling stations as the main effect variable; Table S4. Carbon stock (Mg ha-1) of vegetation in different sampling stations of the wetland and Kruskal-Wallis test with habitat conditions under different sampling stations as the main effect variable; Table S5. Detailed results of multiple regression analysis (using backward method) for carbon stock in wetland vegetation against the micro-topographic parameter...
Additional file 2: Figure S1. Flood-phase wise variations in species richness (a), Shannon-Wiener... more Additional file 2: Figure S1. Flood-phase wise variations in species richness (a), Shannon-Wiener diversity index (b), Simpson dominance index (c), Buzas and Gibson's evenness index (d), and Taxonomic distinctness (e) of the wetland vegetation; Figure S2. Flood phase wise dominance–diversity curve of wetland vegetation in different sampling stations; a- Early flood phase, b- Mid-flood phase, c- Late flood phase; Station 1- inlet point 1; Station 2- middle point 1; Station 3- inlet point 2; Station 4- middle point 2 and Station 5- outlet point; Figure S3. Flood-phase wise variations in micro-topography and water flow regime of the wetland; depth (a), width (b), cross-sectional area (c), water velocity (d), and water discharge (e); Figure S4. Flood-phase wise variations in carbon stock in wetland vegetation
A preliminary investigation was carried out in Fulbari 'anuo ', Cachar, Assam during 20... more A preliminary investigation was carried out in Fulbari 'anuo ', Cachar, Assam during 20 I0, in order to gather information on the presence of phytoplankton and zoopl ankton communities and their habitat conditions. The study showed that Fulbari 'anua ' is relatively in satisfactory conditions in terms of physico-chemical properties of water and its planktonic communities. Dominance of Bacill ariophyceae and Chlorophyceae amongst phytoplankton and Calanoida amongst zoopl ankton indicate oligotrophic to mesotrophic status of the 'anua '. The study also revealed the prospect offishery like pan and cage cultures in some of its patches. Besides, this study suggests initiation ofsome management measures especially in relation to the dense aquatic macrophytes. This study also highlights the prospect of this oxbow lake for enhancing the socio-economic status of the riparian people by proper management measures and sustainable utilization ofits resource.
The suspended algal life forms (SALF) were studied in the high altitude rice fields (WRF) coverin... more The suspended algal life forms (SALF) were studied in the high altitude rice fields (WRF) covering five randomly selected sites of Apatani Plateau in Arunachal Pradesh, India. The samples were collected fortnightly from WRF in three inundated phases viz. water accumulation (April- May), flooding (June-July) and early recession (August –September) during the rice growing season of 2013. A total of 62 taxa of SALF belonging to the classes Chlorophyceae, Bacillariophyceae and Cyanophyceae were recorded. Closterium sp., Spondylosium sp., Scenedesmus sp., Ulothrix sp., Zygnema sp., Spirogyra sp., Docidium sp. of Chlorophyceae, Navicula sp., Pinnularia sp., Rhizosolenia sp., Tabellaria sp. of Bacillariophyceae and Oscillatoria sp., Nostoc sp., Phormidium sp. of Cyanophyceae were in high abundance in WRF. The study also revealed that Chlorophyceae was the most dominant and diverse class of SALF followed by Bacillariophyceae and Cyanophyceae which was ensued for concurrent existence of rice...
Traditional ecological knowledge (TEK) systems illustrate various ways and means of natural resou... more Traditional ecological knowledge (TEK) systems illustrate various ways and means of natural resource utilization and management, which has come into being through keen observations as well as the age-old trial and error methods. However, such knowledge systems are gradually eroding due to various reasons. Proper documentation, characterization, scientific validation, and popularization of such knowledge systems would help in preserving them for posterity. The present study characterizes the ecological attributes of a traditional rice farming system called Asra in Karimganj district of Barak Valley, Assam. The objective was to investigate the water properties and community composition of plankton and rice stem epiphyton of the water logged Asra rice field agro-ecosystem. The substantial contribution of Asra rice field ecosystems in maintaining the overall biodiversity of the system has been highlighted in the present study. The study revealed the presence of 77 genera of phytoplankto...
Wetlands store an enormous amount of carbon in its different biophysical components, namely veget... more Wetlands store an enormous amount of carbon in its different biophysical components, namely vegetation, soil, and sediment, thus playing an important role in mitigating climate change. Floodplain wetlands cover substantial area in northeast India. They are seasonally inundated by nutrient-rich floodwater that facilitates luxuriant growth of shrubs, herbs, and pteridophytes. High productivity and rapid turnover of such plants may play an important role in carbon-stocking and sequestration in such wetlands. We tested this proposition in Chatla, a seasonal floodplain wetland in Assam, Northeast India by estimating the carbon stock and sequestration of vegetation and soil. The estimated total carbon stock was 21.75 Mg C ha−1. Of this, the vegetation component contributed 3.18 Mg C ha−1 (14.62%), saturated soil contributed 8.53 Mg C ha−1 (39.22%), and unsaturated soil contributed 10.04 Mg C ha−1 (46.16%). The carbon sequestration potential of Chatla was estimated to be 6.36 Mg C ha−1 yea...
Plankton composition and abundance in aquatic systems is determined and regulated naturally by th... more Plankton composition and abundance in aquatic systems is determined and regulated naturally by the prevailing environmental conditions, and are expected to be at equilibrium. However, human induced environmental factors such as land use change putatively disturb such equilibrium leading to change in the composition, abundance and dominance patterns. Therefore, it is important to study how planktonic communities are affected by the change in the aquatic environmental parameters. In the present study, we studied the community composition of plankton in the aquatic bodies formed in agricultural lands as a result of excavation of soil for brick making. We also characterized the aquatic environment through analysis of water properties of selected aquatic bodies. We recorded a total of 48 genera of phytoplankton and 27 genera of zooplankton communities. Amongst phytoplankton, Bacillariophyceae was the most dominant class with 20 numbers of genera, followed by Chlorophyceae (11) and Cyanop...
Water in rice fields of mountain valley of Ziro, Arunachal Pradesh was investigated for physico-c... more Water in rice fields of mountain valley of Ziro, Arunachal Pradesh was investigated for physico-chemical characterization during rice fish farming season (Kharif) of 2013. Water temperature, dissolved oxygen, biological oxygen demand, free carbon dioxide, nitrate-nitrogen, phosphate-phosphorus, chloride, total hardness, calcium hardness, alkalinity, pH, total dissolved solids, specific conductivity and water depth were studied. This study revealed that the physical parameters of water in rice fields like water temperature, pH, total dissolved solids, specific conductivity and water depth were 23.5-31.3 degrees C, 5.9-6.9, 250.34-370.5 mgl(-1), 437.75-660.33 μScm(-1) and 3.72-16.9 cm respectively. The chemical features like dissolved oxygen, biological oxygen demand, free CO2, nitrate-nitrogen, phosphate-phosphorus, chloride, total hardness Ca hardness, alkalinity were 2.4-12.9 mgl(-1), 1.5-11.1 mgl(-1), 9.7-23.35 mgl(-1), 1.28-3.9 mgl(-1), 0.005-0.539 mgl(-1), 16.6-46.8 mgl(-1), 13....
Assam University Journal of Science and Technology, 2011
A preliminmy investigation was carried out in Fulbari ' anua', Cachar, Assam during 2010,... more A preliminmy investigation was carried out in Fulbari ' anua', Cachar, Assam during 2010, in order to gather information on the presence of phytoplankton and zooplankton communities and their habitat conditions. The study showed that Fulbari 'anua' is relatively in satisfactory conditions in terms of physicochemical properties of water and its planktonic communities. Dominance of Bacillariophyceae and Chlorophyceae amongst phytoplankton and Calanoida amongst zooplankton indicate oligotrophic to mesotrophic status of the 'anua '. The study also revealed the prospect of fishery like pan and cage cultures in some of its patches. Besides, this study suggests initiation of some management measures especially in relation to the dense aquatic macrophytes. This study also highlights the prospect of this oxbow lake for enhancing the socio-economic status of the riparian people by proper management measures and sustainable utilization of its resource.
Assam University Journal of Science and Technology, 2010
A study on the biomass and productivity of riparian vegetation along Dikrong river system compris... more A study on the biomass and productivity of riparian vegetation along Dikrong river system comprising three rivers, Pare, Pachin and Dikrong in Arunachal Pradesh was carried out. Both the biomass and productivity of the riparian vegetation was greater along river Pare and was least along river Pachin. It was observed that the intensity of disturbance along the riparian zone played a significant role in decreasing both the biomass and productivity of the riparian vegetation. Hence proper management initiatives should be taken to maintain the riparian vegetation as it plays a significant role in the functioning of riverine systems.
ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat ... more ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat straw (WS), potato plant (PP), and mustard stover (MS) were prepared with or without fish pond bottom sediment to investigate the compost maturity and their suitability for field application. The composting process was monitored through the changes in physico‐chemical parameters and germination index (GI) at every 7 days interval of the composting process. All the composts were dark brown and smelled like forest soil within 56 days of composting, which reflected its matured status. On the basis of the physico‐chemical parameters (bulk density: 0.84 g/cm3; pH 7.05; electrical conductivity: 3.52 mS/cm; cation exchange capacity:82.4 cmol/kg; total carbon:321.4 g/kg; total nitrogen: 16.9 g/kg; As: 6.8 mg/kg; Cd: 2.96 mg/kg; Cr: 29.6 mg/kg, Cu: 243.6 mg/kg; Hg: 0.019 mg/kg; Ni: 24.3 mg/kg; Pb: 62.1 mg/kg and Zn: 812 mg/kg) and GI (89–96%), it could be concluded that RS/WS/PP/MS, 1:1:2:1 v/v/v/v with fish pond sediment produced better compost in accordance with the Indian compost standard. Application of a combined randomized block design analysis revealed that there is a significant difference in the responses of the five composts, in relation to the time of composting. Hierarchical clustering algorithm was applied with a view to form homogeneous groups of five different composts on the basis of different physico‐chemical parameters. Therefore, the ratio of waste incorporation is an important decision for composting and addition of pond sediment can improve the quality of compost.
ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat ... more ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat straw (WS), potato plant (PP), and mustard stover (MS) were prepared with or without fish pond bottom sediment to investigate the compost maturity and their suitability for field application. The composting process was monitored through the changes in physico‐chemical parameters and germination index (GI) at every 7 days interval of the composting process. All the composts were dark brown and smelled like forest soil within 56 days of composting, which reflected its matured status. On the basis of the physico‐chemical parameters (bulk density: 0.84 g/cm3; pH 7.05; electrical conductivity: 3.52 mS/cm; cation exchange capacity:82.4 cmol/kg; total carbon:321.4 g/kg; total nitrogen: 16.9 g/kg; As: 6.8 mg/kg; Cd: 2.96 mg/kg; Cr: 29.6 mg/kg, Cu: 243.6 mg/kg; Hg: 0.019 mg/kg; Ni: 24.3 mg/kg; Pb: 62.1 mg/kg and Zn: 812 mg/kg) and GI (89–96%), it could be concluded that RS/WS/PP/MS, 1:1:2:1 v/v/v/v with fish pond sediment produced better compost in accordance with the Indian compost standard. Application of a combined randomized block design analysis revealed that there is a significant difference in the responses of the five composts, in relation to the time of composting. Hierarchical clustering algorithm was applied with a view to form homogeneous groups of five different composts on the basis of different physico‐chemical parameters. Therefore, the ratio of waste incorporation is an important decision for composting and addition of pond sediment can improve the quality of compost.
Additional file 1: Table S1. Distribution and density (no. of individuals ha-1) of vegetation acr... more Additional file 1: Table S1. Distribution and density (no. of individuals ha-1) of vegetation across various sampling stations of the wetland and Kruskal-Wallis test with habitat conditions under different sampling stations as the main effect variable; Table S2. One-way analyses of variance for micro-topography, water flow regime and vegetation attributes in the wetland with flood phases as the main effect variable; Table S3. Importance Value Index (IVI) of vegetation across various sampling stations of the wetland and Kruskal-Wallis test with habitat conditions under different sampling stations as the main effect variable; Table S4. Carbon stock (Mg ha-1) of vegetation in different sampling stations of the wetland and Kruskal-Wallis test with habitat conditions under different sampling stations as the main effect variable; Table S5. Detailed results of multiple regression analysis (using backward method) for carbon stock in wetland vegetation against the micro-topographic parameter...
Additional file 2: Figure S1. Flood-phase wise variations in species richness (a), Shannon-Wiener... more Additional file 2: Figure S1. Flood-phase wise variations in species richness (a), Shannon-Wiener diversity index (b), Simpson dominance index (c), Buzas and Gibson's evenness index (d), and Taxonomic distinctness (e) of the wetland vegetation; Figure S2. Flood phase wise dominance–diversity curve of wetland vegetation in different sampling stations; a- Early flood phase, b- Mid-flood phase, c- Late flood phase; Station 1- inlet point 1; Station 2- middle point 1; Station 3- inlet point 2; Station 4- middle point 2 and Station 5- outlet point; Figure S3. Flood-phase wise variations in micro-topography and water flow regime of the wetland; depth (a), width (b), cross-sectional area (c), water velocity (d), and water discharge (e); Figure S4. Flood-phase wise variations in carbon stock in wetland vegetation
A preliminary investigation was carried out in Fulbari 'anuo ', Cachar, Assam during 20... more A preliminary investigation was carried out in Fulbari 'anuo ', Cachar, Assam during 20 I0, in order to gather information on the presence of phytoplankton and zoopl ankton communities and their habitat conditions. The study showed that Fulbari 'anua ' is relatively in satisfactory conditions in terms of physico-chemical properties of water and its planktonic communities. Dominance of Bacill ariophyceae and Chlorophyceae amongst phytoplankton and Calanoida amongst zoopl ankton indicate oligotrophic to mesotrophic status of the 'anua '. The study also revealed the prospect offishery like pan and cage cultures in some of its patches. Besides, this study suggests initiation ofsome management measures especially in relation to the dense aquatic macrophytes. This study also highlights the prospect of this oxbow lake for enhancing the socio-economic status of the riparian people by proper management measures and sustainable utilization ofits resource.
The suspended algal life forms (SALF) were studied in the high altitude rice fields (WRF) coverin... more The suspended algal life forms (SALF) were studied in the high altitude rice fields (WRF) covering five randomly selected sites of Apatani Plateau in Arunachal Pradesh, India. The samples were collected fortnightly from WRF in three inundated phases viz. water accumulation (April- May), flooding (June-July) and early recession (August –September) during the rice growing season of 2013. A total of 62 taxa of SALF belonging to the classes Chlorophyceae, Bacillariophyceae and Cyanophyceae were recorded. Closterium sp., Spondylosium sp., Scenedesmus sp., Ulothrix sp., Zygnema sp., Spirogyra sp., Docidium sp. of Chlorophyceae, Navicula sp., Pinnularia sp., Rhizosolenia sp., Tabellaria sp. of Bacillariophyceae and Oscillatoria sp., Nostoc sp., Phormidium sp. of Cyanophyceae were in high abundance in WRF. The study also revealed that Chlorophyceae was the most dominant and diverse class of SALF followed by Bacillariophyceae and Cyanophyceae which was ensued for concurrent existence of rice...
Traditional ecological knowledge (TEK) systems illustrate various ways and means of natural resou... more Traditional ecological knowledge (TEK) systems illustrate various ways and means of natural resource utilization and management, which has come into being through keen observations as well as the age-old trial and error methods. However, such knowledge systems are gradually eroding due to various reasons. Proper documentation, characterization, scientific validation, and popularization of such knowledge systems would help in preserving them for posterity. The present study characterizes the ecological attributes of a traditional rice farming system called Asra in Karimganj district of Barak Valley, Assam. The objective was to investigate the water properties and community composition of plankton and rice stem epiphyton of the water logged Asra rice field agro-ecosystem. The substantial contribution of Asra rice field ecosystems in maintaining the overall biodiversity of the system has been highlighted in the present study. The study revealed the presence of 77 genera of phytoplankto...
Wetlands store an enormous amount of carbon in its different biophysical components, namely veget... more Wetlands store an enormous amount of carbon in its different biophysical components, namely vegetation, soil, and sediment, thus playing an important role in mitigating climate change. Floodplain wetlands cover substantial area in northeast India. They are seasonally inundated by nutrient-rich floodwater that facilitates luxuriant growth of shrubs, herbs, and pteridophytes. High productivity and rapid turnover of such plants may play an important role in carbon-stocking and sequestration in such wetlands. We tested this proposition in Chatla, a seasonal floodplain wetland in Assam, Northeast India by estimating the carbon stock and sequestration of vegetation and soil. The estimated total carbon stock was 21.75 Mg C ha−1. Of this, the vegetation component contributed 3.18 Mg C ha−1 (14.62%), saturated soil contributed 8.53 Mg C ha−1 (39.22%), and unsaturated soil contributed 10.04 Mg C ha−1 (46.16%). The carbon sequestration potential of Chatla was estimated to be 6.36 Mg C ha−1 yea...
Plankton composition and abundance in aquatic systems is determined and regulated naturally by th... more Plankton composition and abundance in aquatic systems is determined and regulated naturally by the prevailing environmental conditions, and are expected to be at equilibrium. However, human induced environmental factors such as land use change putatively disturb such equilibrium leading to change in the composition, abundance and dominance patterns. Therefore, it is important to study how planktonic communities are affected by the change in the aquatic environmental parameters. In the present study, we studied the community composition of plankton in the aquatic bodies formed in agricultural lands as a result of excavation of soil for brick making. We also characterized the aquatic environment through analysis of water properties of selected aquatic bodies. We recorded a total of 48 genera of phytoplankton and 27 genera of zooplankton communities. Amongst phytoplankton, Bacillariophyceae was the most dominant class with 20 numbers of genera, followed by Chlorophyceae (11) and Cyanop...
Water in rice fields of mountain valley of Ziro, Arunachal Pradesh was investigated for physico-c... more Water in rice fields of mountain valley of Ziro, Arunachal Pradesh was investigated for physico-chemical characterization during rice fish farming season (Kharif) of 2013. Water temperature, dissolved oxygen, biological oxygen demand, free carbon dioxide, nitrate-nitrogen, phosphate-phosphorus, chloride, total hardness, calcium hardness, alkalinity, pH, total dissolved solids, specific conductivity and water depth were studied. This study revealed that the physical parameters of water in rice fields like water temperature, pH, total dissolved solids, specific conductivity and water depth were 23.5-31.3 degrees C, 5.9-6.9, 250.34-370.5 mgl(-1), 437.75-660.33 μScm(-1) and 3.72-16.9 cm respectively. The chemical features like dissolved oxygen, biological oxygen demand, free CO2, nitrate-nitrogen, phosphate-phosphorus, chloride, total hardness Ca hardness, alkalinity were 2.4-12.9 mgl(-1), 1.5-11.1 mgl(-1), 9.7-23.35 mgl(-1), 1.28-3.9 mgl(-1), 0.005-0.539 mgl(-1), 16.6-46.8 mgl(-1), 13....
Assam University Journal of Science and Technology, 2011
A preliminmy investigation was carried out in Fulbari ' anua', Cachar, Assam during 2010,... more A preliminmy investigation was carried out in Fulbari ' anua', Cachar, Assam during 2010, in order to gather information on the presence of phytoplankton and zooplankton communities and their habitat conditions. The study showed that Fulbari 'anua' is relatively in satisfactory conditions in terms of physicochemical properties of water and its planktonic communities. Dominance of Bacillariophyceae and Chlorophyceae amongst phytoplankton and Calanoida amongst zooplankton indicate oligotrophic to mesotrophic status of the 'anua '. The study also revealed the prospect of fishery like pan and cage cultures in some of its patches. Besides, this study suggests initiation of some management measures especially in relation to the dense aquatic macrophytes. This study also highlights the prospect of this oxbow lake for enhancing the socio-economic status of the riparian people by proper management measures and sustainable utilization of its resource.
Assam University Journal of Science and Technology, 2010
A study on the biomass and productivity of riparian vegetation along Dikrong river system compris... more A study on the biomass and productivity of riparian vegetation along Dikrong river system comprising three rivers, Pare, Pachin and Dikrong in Arunachal Pradesh was carried out. Both the biomass and productivity of the riparian vegetation was greater along river Pare and was least along river Pachin. It was observed that the intensity of disturbance along the riparian zone played a significant role in decreasing both the biomass and productivity of the riparian vegetation. Hence proper management initiatives should be taken to maintain the riparian vegetation as it plays a significant role in the functioning of riverine systems.
ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat ... more ABSTRACT Composts with five different ratios of agricultural wastes, viz. rice straw (RS), wheat straw (WS), potato plant (PP), and mustard stover (MS) were prepared with or without fish pond bottom sediment to investigate the compost maturity and their suitability for field application. The composting process was monitored through the changes in physico‐chemical parameters and germination index (GI) at every 7 days interval of the composting process. All the composts were dark brown and smelled like forest soil within 56 days of composting, which reflected its matured status. On the basis of the physico‐chemical parameters (bulk density: 0.84 g/cm3; pH 7.05; electrical conductivity: 3.52 mS/cm; cation exchange capacity:82.4 cmol/kg; total carbon:321.4 g/kg; total nitrogen: 16.9 g/kg; As: 6.8 mg/kg; Cd: 2.96 mg/kg; Cr: 29.6 mg/kg, Cu: 243.6 mg/kg; Hg: 0.019 mg/kg; Ni: 24.3 mg/kg; Pb: 62.1 mg/kg and Zn: 812 mg/kg) and GI (89–96%), it could be concluded that RS/WS/PP/MS, 1:1:2:1 v/v/v/v with fish pond sediment produced better compost in accordance with the Indian compost standard. Application of a combined randomized block design analysis revealed that there is a significant difference in the responses of the five composts, in relation to the time of composting. Hierarchical clustering algorithm was applied with a view to form homogeneous groups of five different composts on the basis of different physico‐chemical parameters. Therefore, the ratio of waste incorporation is an important decision for composting and addition of pond sediment can improve the quality of compost.
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