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Effects of clump spacing on nutrient distribution and root activity of Dendrocalamus strictus in the humid region of Kerala,peninsular India

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Journal of Forestry Research 2017年第6期28卷 1133-1144页

作者： B. H. Kittur K. Sudhakara B. Mohan kumar T. K. Kunhamu P. Sureshkumar Department of Silviculture and Agroforestry College of Forestry Kerala Agricultural UniversityVellanikkara Thrissur Kerala 680656 India School of Ecology and Environment Studies Nalanda University Rajgir District Nalanda Bihar 803116 India Department of Soil Science and Agricultural Chemistry Radio-tracer Laboratory College of Horticulture Kerala Agricultural University Vellanikkara ThrissurKerala 680656 India

The humid agroclimatic conditions of Kerala,India permit the cultivation of an array of bamboo species of which Dendrocalamus strictus Roxb.(Nees.) is an important one on account of its high growth rate and multiple uses. Stand density, a potential tool in controlling the productivity of woody ecosystems, its effect on growth and root distribution patterns may provide a better understanding of productivity optimization especially when bamboo-based intercropping options are *** attributes of 7-year-old bamboo(D. strictus) stands managed at variable spacing(4×4 m, 6×6 m, 8×8 m,10×10 m, 12×12 m) were studied. Functional root activity among bamboo clumps were also studied using a radio tracer soil injection method in which the radio isotopeP was applied to soil at varying depths and lateral distances from the clump. Results indicate that spacing exerts a profound influence on growth of bamboo. Widely spaced bamboo exhibited higher clump diameters and crown widths while clump heights were better under closer spacing. Clump height was 30% lower and DBH 52%higher at the widest spacing(12×12 m) compared to the closest spacing(4×4 m). With increasing soil depth and lateral distance, root activity decreased significantly. Root activity near the clump base was highest(809 counts per minute, cpm; 50 cm depth and 50 cm lateral distance) at 4×4 m. Tracer study further showed wider distribution of root activity with increase in clump spacing. It may be concluded that the intensive foraging zone of bamboo is within a 50-cm radius around the clump irrespective of spacing. N, P and K content in the upper 20 cm was 2197,21, and 203 kg/ha respectively for the closely spaced bamboo(4×4 m) which were significantly higher than corresponding nutrient content at wider spacings. About 50% of N, P and K were present within the 0–20 cm soil layer, which decreased drastically beyond the 20 cm *** results suggest that stand management practices through planting density regula

关键词： Bamboo Clump spacing Functional root activity Radio tracer 32P Soil nutrients

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Tree assemblages and diversity patterns in Tropical Juri Forest,Bangladesh

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Journal of Forestry Research 2015年第1期26卷 159-169页

作者： Swapan kumar Sarker Muhammad Nur-Un-Nabi Md.Mohasinul haque Mahmuda Sharmin Sanjay Saha Sonet Sourav Das Niamjit Das Department of Forestry and Environmental Science Shahjalal University of Science & Technology

Juri is a biodiversity-rich primary forest in Bangladesh, which remains ecologically unexplored. We identified tree species and examined the richness, alpha（a）diversity and floristic similarity patterns within the identified communities. Vegetation and environmental data were sampled in 120（0.04 ha） study plots. Tree communities were delimited by two-way indicator species analysis（TWINSPAN）. In total, 78 tree species of 35 families and58 genera were identified. TWINSPAN identified six tree communities： A—Tricalysia singularis; B—Kydia calycina-Castanopsis tribuloides; C—Polyalthia simiarum-Duabanga grandiflora; D—Ficus roxburghii; E—Artocarpus lacucha; F—Artocarpus lacucha. Mean richness, Shannon and Gini-Simpson indices were highest for the Polyalthia simiarum-Duabanga grandiflora community, while Ficus roxburghii showed lowest diversity. Significant differences（p = 0.05） in three diversity indices were recorded between Polyalthia simiarum-Duabanga grandiflora and Ficus roxburghii. Tree compositional similarity was greatest between Kydia calycina-Castanopsis tribuloides and Polyalthia simiarum-Duabanga grandiflora（0.712）.

关键词： Two-way indicator species analysis(TWINSPAN) Richness index Shannon index Gini-Simpson index Tropical forest Conservation

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Integrated Approach of Universal Soil Loss Equation (USLE) and Geographical Information System (GIS) for Soil Loss Risk Assessment in Upper South Koel Basin, Jharkhand

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Journal of Geographic Information System 2012年第6期4卷 588-596页

作者： Reshma Parveen Uday kumar University Department of Geology Ranchi University Ranchi India

Soil erosion is a growing problem especially in areas of agricultural activity where soil erosion not only leads to decreased agricultural productivity but also reduces water availability. Universal Soil Loss Equation (USLE) is the most popular empirically based model used globally for erosion prediction and control. Remote sensing and GIS techniques have become valuable tools specially when assessing erosion at larger scales due to the amount of data needed and the greater area coverage. The present study area is a part of Chotanagpur plateau with undulating topography, with a very high risk of soil erosion. In the present study an attempt has been made to assess the annual soil loss in Upper South Koel basin using Universal Soil Loss Equation (USLE) in GIS framework. Such information can be of immense help in identifying priority areas for implementation of erosion control measures. The soil erosion rate was determined as a function of land topography, soil texture, land use/land cover, rainfall erosivity, and crop management and practice in the watershed using the Universal Soil Loss Equation (for Indian conditions), remote sensing imagery, and GIS techniques. The rainfall erosivity R-factor of USLE was found as 546 MJ mm/ha/hr/yr and the soil erodibility K-factor varied from 0.23 - 0.37. Slopes in the catchment varied between 0% and 42% having LS factor values ranging from 0 - 21. The C factor was computed from NDVI (Normalized Difference Vegetative Index) values derived from Landsat-TM data. The P value was computed from existing cropping patterns in the catchment. The annual soil loss estimated in the watershed using USLE is 12.2 ton/ha/yr.

关键词： Universal Soil Loss Equation (USLE) Remote Sensing & GIS Soil Loss

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Integrative assessment of biomarker responses in teleostean fishes exposed to glyphosate-based herbicide(Excel Mera 71)

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Emerging Contaminants 2016年第4期2卷 191-203页

作者： Sukhendu Dey Palas Samanta Sandipan Pal Aloke kumar Mukherjee Debraj Kole Apurba Ratan Ghosh Ecotoxicology Lab Department of Environmental ScienceThe University of BurdwanGolapbagBurdwan 713104West BengalIndia Division of Environmental Science and Ecological Engineering Korea UniversityAnam-dongSungbuk-guSeoul 02841Republic of Korea Department of Environmental Science Aghorekamini Prakashchandra MahavidyalayaSubhasnagarBengaiHooghly 712611West BengalIndia P.G.Department of Conservation Biology Durgapur Govt.CollegeDurgapur 713214West BengalIndia

Present study deals with the effects of glyphosate-based herbicide,Excel Mera 71 on Anabas testudineus,Heteropnestes fossilis and Oreochromis niloticus in field conditions(1.85 kg/ha)based on anti-oxidative,metabolic and digestive *** this study following biomarkers viz.,acetylcholinesterase(AChE),lipid peroxidation(LPO),catalase(CAT),glutathione-S-transferase(GST),alkaline phosphatase(ALP),aspartate aminotransferase(AST),alanine aminotransferase(ALT),amylase,lipase and protease were investigated in gill,stomach,intestine,liver,kidney,brain,muscle and spinal cord of the concerned fish *** activities were significantly altered by glyphosate exposure after 30 days,these activities were tissue as well as species *** results suggested that these biomarkers could be used to assess the ecological risks of glyphosate on *** factor(BAF)studied in different aquatic natural macrophytes showed order of Alternanthera philoxeroides>Azolla pinnata>Lemna sp.(Minor)>Lemna sp.(Major)>Pistia stratiotes,while transfer factor(TF)showed the order of Pistia stratiotes>Alternanthera philoxeroides>Lemna *** factor(BCF)study showed maximum accumulation of glyphosate in liver,kidney or intestine,and minimum either in bone or stomach irrespective of fish *** integrated biomarker response(IBR),which uses a battery of biomarkers to calculate the standardized scores for each biomarker responses ranging from physiological to biochemical/molecular responses,was evaluated by combining the multiple biomarkers into a single value to evaluate quantitatively the toxicological effects of *** general,the multiple indices exhibited variations and *** was more affected than other fish species;maximum IBR value was observed for LPO and minimum in case of *** order of integrated biomarkers caused by glyphosate treatment was recorded as follows:LPO>Amylase>CAT>AST>Protease>Lipase>ALP>GST>AChE>ALT for ***,LP

关键词： Excel Mera 71 Biomarker Bioaccumulation factor(BAF) Bioconcentration factor(BCF) Transfer factor(TF) Integrated biomarker response(IBR)

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Crop productivity,soil health,and energy dynamics of Indian Himalayan intensified organic maize-based systems

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International Soil and Water Conservation Research 2021年第2期9卷 260-270页

作者： Raghavendra Singh Subhash Babu R.K.Avasthe Gulab Singh Yadav Anup Das K.P.Mohapatra Amit kumar Vinod K.Singh Puran Chandra ICAR-National Organic Farming Research Institute GangtokSikkim737102India Division of Agronomy ICAR-Indian Agricultural Research InstituteNew Delhi110012India ICAR Research Complex for NEH Region Tripura CentreLembucherraTripura799210India ICAR-National Bureau of Plant Genetic Resources New Delhi110012India

The sustainability of prevailing maize-fallow system in rainfed ecosystems of the Eastern Himalayan region(EHR)of India is often questioned due to poor economic return and negative impact on soil ***,the six cropping systems,maize-fallow(M-F),maize t cowpea-rapeseed(M t C-Rs),maize t cowpea-buckwheat(M t C-Bw),maize t cowpea-barley(M t CeB),maize t cowpea-garden pea(M t C-GP)and maize t cowpeaerajmash(M t C-R)in the main plot and three soil moisture conservation measures,no-mulch(NM),maize stover mulch(MSM)and maize stover t weed biomass mulch(MSM t WBM)in sub-plot were evaluated for four consecutive years(2014-18)at a Research Farm in fixed plot *** indicated that cowpea co-culture with maize and inclusion of winter crop increased maize yield by 6.2e23.5%over *** the systems,the M t C-GP recorded the highest crop *** residual effect of MSM t WBM increased maize grain yield by 19.1%over *** of maize t cowpea-winter crops significantly improved the available N(3.2e12.9%),P(3.6 e12.7%),K(1.9e26.3%),organic carbon(9.2e16.8%),microbial biomass carbon-MBC(15.2e43.9%)and dehydrogenases-Dha(17.2e42.3%)in soil at 0e15 cm depth as compared to *** M t C-GP also recorded maximum net return(US$2460 ha1),benefit:cost(B:C)ratio(2.86)and energy use efficiency(7.9%).The MSM t WBM recorded higher net return(US$1680 ha1)and B:C ratio(2.46)over ***,cowpea t maize-garden pea(M t C-GP)along with the application of MSM t WBM is a sustainable production practice to intensify the organically managed maize-fallow system in rainfed regions of the EHR of India and other similar ecosystems.

关键词： Crop intensification Energy productivity Gross return Soil health Water productivity

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Liquid-Liquid Extraction of V(IV) from Sulphate Medium by Cyanex 301 Dissolved in Kerosene

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International Journal of Nonferrous Metallurgy 2013年第1期2卷 21-29页

作者： Ranjit kumar Biswas Aneek Krishna Karmakar Department of Applied Chemistry and Chemical Engineering Rajshahi University Rajshahi Bangladesh

The equilibrium of extraction of V(IV) in the V(IV)- SO42- (H+, Na+)-Cyanex 301 (ha)-kerosene system has been studied. Significant extraction occurs above pH 1 within 10 min. CD (extraction ratio at constant pH(eq) and [ha](o,eq)) value is slightly decreased with increasing [V(IV)](ini). CD is found to be directly proportional to [H+]-n (n ≤ 2), [ha] 2 and (1+1.58 [SO42-]). The process is endothermic (DH = 16 kJ/mol). Apparent Kexvalues at 303 K are 10-1.419 and 10-0.94 in 0.10 and 1.50 mol/L SO42- medium, respectively. The loading capacity is calculated to be7.87 gV(IV) per100 g Cyanex 301. Kerosene appears as the best diluent. Stripping to the extents of 100%, 94% and 97.7% are possible in single stage by 1 mol/L H2SO4, HCl and HNO3, respectively. Separations of V(IV) from Cu(II) (at pH 0), Zn(II) (at pH 0.5) and Fe(III) (at pH 1.0) by Cyanex 301 are possible.

关键词： Extraction Equilibrium Vanadium(IV) Cyanex 301 Kerosene Sulphate

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Equilibrium of the Extraction of V(IV) in the V(IV)-SO42-(H+, Na+)—Cyanex 302-Kerosene System

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International Journal of Nonferrous Metallurgy 2012年第3期1卷 23-31页

作者： Ranjit kumar Biswas Aneek Krishna Karmakar Department of Applied Chemistry & Chemical Engineering Rajshahi University Rajshahi Bangladesh

The title system has been investigated from the equilibrium point of view. Significant extraction occurs above pH 2. Equilibration time is 20 min. The extraction ratio (D) remains constant with increasing [V(IV)] of at least 0.50 g/L. It is inversely proportional to [H+]2, [H+] and [H+]0.3 in the lower pH (2;and [SO42-]0 and [SO42-]-1 in the lower [SO42-] (42-] (>1 mol/L) regions, respectively. The apparent extraction equilibrium constant (Kex) in 0.02 mol/L SO42- medium and at 303 K is found to vary from 10-3.447 to 101.508 with increasing equilibrium pH from 2.25 to 4.00. Various sulphated, hydrolyzed, hydrated and mixed sulphated hydrolyzed species of V(IV) have been considered at different extraction conditions to propose the extraction equilibrium reactions to form always [VO(ha2)2] as the extractable species. The system is highly temperature dependent with ?H value of ~90 kJ/mol and ~25 kJ/mol in lower and higher temperature regions, respectively. The calculated loading capacity is low (4.05 g V(IV)/100 g Cyanex 302). Kerosene is a better diluent over CHCl3, Cyclo-C6H12 and CCl4;but much better solvents are C6H6, C6H5CH3, n-C7H16,C6H4(CH3)2, petroleum benzin, 1,2-C2H4Cl2, C6H5Cl. Mineral acids (1 mol/L) are able to strip off V(IV) from the organic phase in a single-stage. Using Cyanex 302, almost complete separations of V(IV) from Cu(II) at pH 1.0 and from Ni(II) at pH(eq) 4.5 are possible in a single-stage of extraction;whereas, its separation from Zn(II) at pH(eq) 2.5, Co(II) at pH(eq) 3.5, Fe(III) at pH(eq) 2.0 and Ti(IV) at pH(eq) 2.5 will require counter-current multi-stage extractions.

关键词： Extraction Equilibrium Vanadium(IV) Cyanex 302 Kerosene Sulphate

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New Agri-Silvo-Pastoral Model Utilizing Terrace RiserEnhancing Crop and Livestock Production Developed inNepal

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Journal of Agricultural Science and Technology(A) 2019年第6期9卷 371-389页

作者： Barakoti Tanka Prasad Sah Raj kumar Agricultural Research Station Nepal Agricultural Research CouncilDhankuta 56800PakhribasNepal

Twelve fodder species with maize (Zea mays) and millet (Eleusine coracana) were evaluated under agri-silvo-pastoral system along the Terrace risers (T-risers) of cropping land in the Agricultural Research Station Pakhribas, Nepal. Major aim of innovative agroforestry experiment designed and tested first time in Nepal was to utilize one-third land in risers of cropping terraces due to limited lands of smallholders to produce green fodders needed for livestock. Trees were planted at 1.5 m on the terrace edges and ground fodders at 30-50 cm on the risers. Trees were not allowed to grow tall to avoid shade effect on crops grown in terraces. They were felled at breast height in second year growing coppices for fodder. The results showed higher survival (76% to 100%), growth (1-3 m high) and yield of improved forages and fodder trees indicating potential for cultivation on T-risers. Dry matter (DM) of tree fodders varied 31%-49%, and ground fodders 19%-32%. DM yields ranged 3.0 t/ha (Stylosanthes guanensis) to 26.5 t/ha (Pennisetum purpureum). Combined effects of fodder species on major hill crops, maize and finger millet growth, yield and other attributes were monitored in the terraces. Most mean data were significant and at par between the treatments. Better combinations of tree and ground fodders for higher grain and stover yields (3.1 t/ha and 3.4 t/ha, respectively) of maize were Grewia optiva/Thysalonaema maxima, Desmodium intortum, Ficus auriculata/Setaria anceps, D. intortum (2.7 t/ha and 3.3 t/ha, respectively). Promising combinations for finger millet growth and yields (2-3 t/ha) were G. optiva/T. maxima, Bauhinia purpurea/S. anceps, F. semicordata/P. cetaceum. Soil analysis result showed positive impact of fodders on the risers where organic matter was highly increased after three years. Farmers and stakeholders also evaluated this technology that has been successful and recommended for similar ecological regions.

关键词： Terrace riser fodder trees forage species maize and millet agri-silvo-pastoral system new model.

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EVALUATION OF EROSION PRODUCTIVITY IMPACT CALCULATOR (EPIC) MODEL FOR MIDDLE MOUNTAIN REGION OF NEPAL

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International Journal of Sediment Research 2004年第2期19卷 106-122页

作者： Sohan kumar GHIMIRE,Mukand Singh BABEL Civil Engineer Department of Irrigation Ministry of Water Resources Kathmandu Nepal Associate Professor Water Engineering and Management Asian Institute of Technology P.O. Box 4 Klong Luang

This study verifies the applicability of EPIC model for an erosion plot （61 .2 m2） and an uplandterraced watershed （72 ha） using a total of 94 rainfall events over a study period of two years. Inorder to analyze the effect of storm size on runoff and soil loss processes, rainfall events aredivided into three groups: small （50mm）. Resultsindicate that the model could predict reasonably well the runoff and soil loss from the erosion plotand the watershed for the moderate and large rainfall events. However, the runoff and soil lossprediction for the small rainfall events is found to be poor. On annual basis, both surface runoff andsoil loss predictions match well the observations. In ligh of the importance of the moderate andlarge rainfall events in producing most of the annual runoff and soil loss in the study area, the EPICmodel is applied to assess the impacts of erosion on agricultural productivity and to evaluatemanagement practices to protect watersheds in the

关键词： EPIC Watershed modeling Surface runoff Terraces Erosion plot Soil loss Productivity Nepal

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Carbon stock of trees along an elevational gradient in temperate forests of Kedarnath Wildlife Sanctuary

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Forestry Studies in China 2013年第2期15卷 137-143页

作者： Jahangeer A. BhaT Kaiser IQBAL Munesh kumar A. K. NEGI N. P. TODARIA Department of Forestry and Natural Resources H.N.B. Garhwal University Srinagar (Garhwal)Uttarakhand 249161 India

The estimation of carbon density of high altitude forests was carried out at five different sites along an elevational gradient from 1550 m to 3550 m in a part of Kedarnath Wildlife Sanctuary, which is one of the largest protected areas of the Garhwal Himalaya, India. Among the study sites the above ground biomass density （AGBD） ranged from 202.72 Mg·ha^-1 （Site 5） to 718.75 Mg·ha^-1 （Site 1） and below ground biomass density （BGBD） from 61.00 Mg·ha^-1 （Site 5） to 203.04 Mg·ha^-1 （Site 1）. The total biomass density （TBD） also followed similar trend, where the lowest value （263.73 Mg·ha^-1） was observed at Site 5 and the highest （921.79 Mg·ha^-1） at Site 1. The total carbon density （TCD） ranged from 131.86 Mg·ha^-1 （Site 5） to 460.89 Mg·ha^-1 （Site 1）, which indicates that the carbon density of forests reduces with increasing elevation.

关键词： carbon density Himalaya elevation sanctuary

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