Effects of illite supplementation on in vitro and in vivo rumen fermentation,microbial population and methane emission of Hanwoo steers fed high concentrate diets

This study was conducted to evaluate the effects of feeding supplemental illite to Hanwoo steers on methane (CH₄) emission and rumen fermentation parameters. An in vitro ruminal fermentation technique was conducted using a commercial concentrate as substrate and illite was added at different concentrations as treatments: 0%, 0.5%, 1.0%, and 2.0% illite. Total volatile fatty acids (VFA) were different (P < 0.05) at 24 h of incubation where the highest total VFA was observed at 1.0% of illite. Conversely, lowest CH₄ production (P < 0.01) was found at 1.0% of illite. In the in vivo experiment, two diets were provided, without illite and with addition of 1% illite. An automated head chamber (GreenFeed) system was used to measure enteric CH₄ production. Cattle received illite supplemented feed increased (P < 0.05) total VFA concentrations in the rumen compared with those fed control. Feeding illite numerically decreased CH₄ production (g/day) and yield (g/kg dry matter intake). Rumen microbial population analysis indicated that the population of total bacteria, protozoa and methanogens were lower (P < 0.05) for illite compared with the control. Accordingly, overall results suggested that feeding a diet supplemented with 1% illite can have positive effects on feed fermentation in the rumen and enteric CH₄ mitigation in beef cattle.     

Monocarpk Senescence in Relation to Yield of Sesamum indicum During Source-Sink Alteration

Defoliation hastens senescence of the capsule wall, increased seed weight/capsule and harvest index, promotes seed filling and decreased the post-flowering contribution and yield/plant. Defruiting delayed senescence of the subtending leaf. Treatment of kinetin on the capsule wall increased its chlorophyll, sugar and dry weight and also increased yield by increasing harvest index, seed weight/capsule compared to seed treatment as well as control, although post-flowering contribution reduced significantly. When treated on the capsule wall ABA defers senescence of both leaf and capsule wall and also increased the yield parameters but seed treatment although defers senescence of both the source organs, decreased the yield parameters. Treatment of urea defers senescence of the source organs and also increased yield and capsule number though harvest index was reduced.
It is concluded that contribution from the capsule wall and deferment of senescence of this organ at the post capsule development period determines yield and in normal condition contribution of source is limited by the sink size.     

Disturbance increases negative spatial autocorrelation in species diversity

Context

Ecological processes that shape diversity and spatial pattern of ecological communities are often altered by disturbance. Spatial patterns (spatial autocorrelation) in species diversity are thus expected to change with disturbance.

Objective

When examining spatial patterns, ecologists traditionally lump positive and negative spatial autocorrelation into the overall spatial autocorrelation. By contrast, here we aim to understand disturbance effects on both positive and negative spatial autocorrelation of species richness and evenness, which may be related to environmental filtering and restricted dispersal, and to competition, respectively.

Methods

For 8 years, we monitored the spatial autocorrelation in species richness and evenness of riparian plant communities in both uncut control and experimentally clearcut sites in the boreal forest of Alberta, Canada. The overall spatial autocorrelation for each of these two indices of diversity was separately decomposed into the components of positive and negative spatial autocorrelations through eigendecomposition of the spatial weighting matrix.

Results

Negative spatial autocorrelation in richness and evenness were more pronounced in the clearcut than uncut sites, although positive spatial autocorrelations in all indices of diversity remained unchanged. Effect of disturbance was not detected on the overall spatial autocorrelation.

Conclusions

Disturbance increases negative spatial autocorrelation in species richness and evenness, with a stronger increase in evenness than richness, which underscores the importance of competition in structuring post-disturbance riparian communities. Our results also highlight the need for assessing positive and negative spatial autocorrelation and different aspects of diversity separately in understanding disturbance effects on the spatial pattern, or identifying processes from patterns.

     

Soil loss tolerance values for different physiographic regions of Central India

In India, a single soil loss tolerance ( T ) value of 11.2 Mg/ha is by default used for formulating land restoration strategies for all soil types, climates and vegetation covers. However, this single 'T' value does not represent a true picture of soil loss tolerance under all land uses. The objective of our study was to develop adjusted ' T ' values for Central India using soil infiltration rate, bulk density, total organic carbon, erodibility and soil pH. Soil state was defined using a quantitative model involving different soil functions which were used to convert soil parameters to a 0 to 1 scale. The normalized values were then multiplied by appropriate weighing factors based on relative importance and sensitivity analysis of each indicator. Based on overall assessment, each soil mapping unit was categorized into soil groups I, II or III. A general guideline of USDA – Natural Resource Conservation Service (USDA-NRCS) was followed to calculate soil loss tolerance for each soil group using effective soil depth. Adjusted ' T ' values for Central India ranged from 2.5 to 12.5 Mg/ha compared with a default value of 11.2 Mg/ha. Use of these values for soil mapping units will improve conservation planning and assist with planning the development of sustainable agriculture.     

Nutrient transformations in soil amended with rock phosphate enriched composts for improving productivity of wheat-green gram sequence

The present study focuses on the transformations of nitrogen (N), phosphorus (P), and sulfur (S) in soil amended with rock phosphate (RP) enriched composts prepared using different crop residues under wheat-green gram sequence. Data emanated from the field study revealed that significant buildup in available pools of potassium permanganate (KMnO₄-N), Olsen-P, and calcium chloride (CaCl₂-S) as well as different fractions of N, P, and S were maintained higher under RP enriched composts treated plot than control. The total N, P, and S varied from 979 to 1776, 604 to 1165, and 273 to 464 kg ha^?1, respectively in different treatments. The yield of wheat and green gram was significantly correlated with different fractions of N, P, and S in soil. Results conclude that RP enriched compost could be an alternative and cost-effective option for mitigating the shortage of chemical fertilizers for crop production.     

Physical and mechanical properties of jute, bamboo and coir natural fiber

A systematic study has been carried out to investigate the mechanical and physical properties of jute, bamboo and coir (brown and white) single fibers. The tensile properties (tensile strength, Young’s modulus and strain to failure) were determined by varying span length. Scanning electron microscopic analysis was also carried out to determine the physical properties of fibers in order to correlate with its strength, Young’s modulus and strain to failure. The Young’s modulus and strain to failure were corrected using newly developed equations. The study revealed that with increasing test span length the Young’s modulus increased and tensile strength as well as strain to failure decreased. This is because no extensometer could be used in this test set-up and machine displacement (denoted by α) was used for the modulus determination. It is also attributed that larger span length helps to minimize the machine displacement compared to smaller ones due to the reduced relative effect of slippage in the clamps. Among all fibers, the Young’s modulus of bamboo fiber was the highest. Jute fiber had smoother surface compared to other three examined fibers.     

Evaluation of cotton byproducts as fillers for poly(lactic acid) and low density polyethylene

Polymeric composites based on cotton burr and cottonseed bull have been prepared by melt blending and extrusion. For poly(lactic acid) (PLA) and low-density polyethylene (LDPE), addition of the fillers slightly changed the composite's thermal properties but significantly decreased the composite's mechanical properties. Heat treatment prior to extrusion resulted in composites with better tensile strength and Young's modulus. The use of maleic anhydride and peroxide only slightly improved the physical properties of the LDPE materials, but the effect was less clear for the PLA materials. The PLA-filler composites may be useful for lowering the cost of the materials in applications that can tolerate the decreased properties. In addition, the addition of fillers to LDPE might be beneficial in applications to improve stiffness or to improve biodegradability.     

Nitrogen transformation and carbon sequestration in wetland paddy field of Bangladesh

Paddy and Water Environment - Rice-based cropping systems in Bangladesh have received little consideration of changing nitrogen (N) and carbon (C) in soil. Therefore, this study was conducted at...     

Effect of distillery effluents on plant and soil enzymatic activities and groundnut quality

A field experiment was conducted during the rainy season 2000 to examine the effect of distillery effluents, i.e., biomethanated spent wash (BSW), raw spent wash (RSW), and lagoon sludge (LS) versus recommended NPK+FYM (farmyard manure) on nutritional quality of groundnut (Arachis hypogaea L.) and enzyme activities of plant and soil. The distillery effluents did not affect the oil content (%), crude and true protein contents (%) in groundnut but increased the seed yield and the contents of methionine by 44 % (1.15 g (16 g N)^–1 vs. 0.80 g (16 g N)^–1 in control) and of cysteine by 24 % (1.36 g (16 g N)^–1 vs. 1.10 g (16 g N)^–1 in control). BSW produced the highest seed yield (619 kg ha^–1) followed by RSW (557 kg ha^–1) and LS (472 kg ha^–1). LS recorded the highest total chlorophyll content (2.94 mg (g FW)^–1) in groundnut leaves. Application of BSW and RSW significantly increased the activity of plant peroxidase whereas the plant polyphenol oxidase was higher in BSW only. The application of distillery effluents did not affect the nitrate reductase activity but BSW significantly increased the nitrate content in the rhizosphere soil. The three effluents significantly increased the dehydrogenase and alkaline phosphatase activity more than recommended NPK+FYM.