scholarly journals Effects of Fire and Large Herbivores on Canopy Nitrogen in a Tallgrass Prairie

2019 ◽  
Vol 11 (11) ◽  
pp. 1364 ◽  
Author(s):  
Bohua Ling ◽  
Edward J. Raynor ◽  
Douglas G. Goodin ◽  
Anthony Joern

This study analyzed the spatial heterogeneity of grassland canopy nitrogen in a tallgrass prairie with different treatments of fire and ungulate grazing (long-term bison grazing vs. recent cattle grazing). Variogram analysis was applied to continuous remotely sensed canopy nitrogen images to examine the spatial variability in grassland canopies. Heterogeneity metrics (e.g., the interspersion/juxtaposition index) were calculated from the categorical canopy nitrogen maps and compared among fire and grazing treatments. Results showed that watersheds burned within one year had higher canopy nitrogen content and lower interspersions of high-nitrogen content patches than watersheds with longer fire intervals, suggesting an immediate and transient fire effect on grassland vegetation. In watersheds burned within one year, high-intensity grazing reduced vegetation density, but promoted grassland heterogeneity, as indicated by lower canopy nitrogen concentrations and greater interspersions of high-nitrogen content patches at the grazed sites than at the ungrazed sites. Variogram analyses across watersheds with different grazing histories showed that long-term bison grazing created greater spatial variability of canopy nitrogen than recent grazing by cattle. This comparison between bison and cattle is novel, as few field experiments have evaluated the role of grazing history in driving grassland heterogeneity. Our analyses extend previous research of effects from pyric herbivory on grassland heterogeneity by highlighting the role of grazing history in modulating the spatial and temporal distribution of aboveground nitrogen content in tallgrass prairie vegetation using a remote sensing approach. The comparison of canopy nitrogen properties and the variogram analysis of canopy nitrogen distribution provided by our study are useful for further mapping grassland canopy features and modeling grassland dynamics involving interplays among fire, large grazers, and vegetation communities.

EDIS ◽  
2013 ◽  
Vol 2013 (11) ◽  
Author(s):  
Michael A. Davis ◽  
Doug R. Sloan ◽  
Gerald Kidder ◽  
R. D. Jacobs

Animal manures have been used as natural crop fertilizers for centuries. Because of poultry manure’s high nitrogen content, it has long been recognized as one of the most desirable manures. Besides fertilizing crops, manures also supply other essential plant nutrients and serve as a soil amendment by adding organic matter, which helps improve the soil’s moisture and nutrient retention. Organic matter persistence will vary with temperature, drainage, rainfall, and other environmental factors. This 2-page fact sheet was written by Michael A. Davis, D.R. Sloan, Gerald Kidder, and R.D. Jacobs, and published by the UF Department of Animal Science, November 2013. http://edis.ifas.ufl.edu/aa205


2019 ◽  
Vol 33 (2) ◽  
pp. 1467-1472 ◽  
Author(s):  
Minh-Tuan Nguyen ◽  
Gerhard D. Pirngruber ◽  
Florian Albrieux ◽  
Fabien Chainet ◽  
Melaz Tayakout-Fayolle ◽  
...  

2005 ◽  
Vol 128 (2) ◽  
pp. 99-103 ◽  
Author(s):  
Alberto Bahillo ◽  
Lourdes Armesto ◽  
Andrés Cabanillas ◽  
Juan Otero

Transformation of hide (animal skins) into leather is a complicated process during which significant amounts of wastes are generated. Fluidized bed combustion has been extended to burn different wastes that have problems with their disposal showing its technical feasibility. Considering the characteristics of the leather waste, especially the heating value (12.5-21MJ∕kg), it is a fairly good fuel. Moreover, leather waste has a high volatile matter, 65%, similar to other biomasses and unusual high nitrogen content, 14%. The aim of this work was to study leather wastes combustion in fluidized bed presenting experimental results regarding NOx and N2O emissions. A series of experiments were carried out in a fluidized bed pilot plant to understand the importance of operating parameters such as furnace temperature, oxygen content in gases, staged combustion and residence time on the NOx and N2O emission level. Despite having high nitrogen content, low conversion of N-fuel to NOx and N2O was measured during the combustion of leather waste in BFB. Bed temperature and oxygen content were found as the most important single parameters on N2O emission and only oxygen content has a significant influence on NOx emission. Leather waste exhibits a great NOx∕O2 trend; NOx emission decreases as the oxygen concentration decreases while the effect of combustion temperature on NOx is insignificant. Staged combustion does not give a reduction in NOx.


1985 ◽  
Vol 65 (4) ◽  
pp. 897-903 ◽  
Author(s):  
D. M. VEIRA ◽  
M. IVAN ◽  
G. BUTLER ◽  
J. G. PROULX

Following weaning at 6–7 mo of age, 36 beef steers were used to determine production responses when grass silage was supplemented with barley or fishmeal. The silage was made from direct-cut, formic- acid-treated grass harvested from a mixed sward and had a high nitrogen content but poor fermentation characteristics. The silage was fed ad libitum for 98 days either alone or supplemented with 500 g fishmeal or 500 g barley per day. Both fishmeal and barley increased total dry matter intake (P < 0.01) by an amount equivalent to the quantity of supplement offered but had no effect on silage intake (P > 0.05). Steers fed the fishmeal grew substantially faster than either the barley (0.53 kg/day) or unsupplemented (0.54 kg/day) groups (P < 0.01). Fishmeal supplementation resulted in a large reduction (35%) in the amount of feed required per kilogram of gain. Key words: Cattle, grass silage, fishmeal, growth


2009 ◽  
Vol 48 (42) ◽  
pp. 7884-7887 ◽  
Author(s):  
Xin Jin ◽  
Veerappan V. Balasubramanian ◽  
Sakthivel T. Selvan ◽  
Dhanashri P. Sawant ◽  
Murugulla A. Chari ◽  
...  

2010 ◽  
Vol 2010 (4) ◽  
pp. 346-353
Author(s):  
V. F. Terent’ev ◽  
I. O. Bannykh ◽  
E. V. Blinov ◽  
M. E. Prutskov ◽  
A. G. Kolmakov ◽  
...  

1970 ◽  
Vol 9 (3) ◽  
pp. 168-172
Author(s):  
NK Karn ◽  
BP Shrestha ◽  
GP Khanal ◽  
R Rijal ◽  
P Chaudhary ◽  
...  

Objective: To see the role of methyleprednisolone succinate in the management of acute spinal cord injury. Methods: A randomized control trial was done including the patients with acute spinal cord injury. They were divided into age and gender matched two groups. Patients with presence of active infection, associated open fracture, those on long term steroid and those who did not give consent to participate in the trial were excluded. One group received methyleprednisolone succinate within 8 hours of injury and another group did not receive the drug. Both the groups were managed nonoperatively. The neurological status of the patients was assessed at presentation, once spinal shock was over, at 6th week and 6th month and after one year according to ASIA scoring. Frankel grading was also assessed in every follow up. Conclusion: Methylprednisolone succinct prevents secondary cord injury to a great extent and hence its administration within 8 hours of injury results in a better functional (motor and sensory) outcome. Keywords: acute spinal cord injury; methyleprednisolone succinate DOI: http://dx.doi.org/10.3126/hren.v9i3.5585   HR 2011; 9(3): 168-172


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