Production of organic matter and interference of two grasses at different levels of water supply

1982 ◽  
Vol 7 (4) ◽  
pp. 277-292 ◽  
Author(s):  
Susanne Salinger ◽  
Reinhard Bornkamm
Keyword(s):  
Organic Matter ◽  
Water Supply ◽  
Different Levels

Organic matter transport in New York City drinking-water-supply watersheds

2006 ◽  
Vol 25 (4) ◽  
pp. 912-927 ◽  
Author(s):  
Louis A. Kaplan ◽  
J. Denis Newbold ◽  
David J. Van Horn ◽  
C. L. Dow ◽  
A. K. Aufdenkampe ◽  
...  
Keyword(s):  
New York ◽  
New York City ◽  
Drinking Water ◽  
Organic Matter ◽  
Water Supply ◽  
York City ◽  
Drinking Water Supply ◽  
Matter Transport ◽  
Organic Matter Transport

scholarly journals Priming and substrate quality interactions in soil organic matter models

2013 ◽  
Vol 10 (3) ◽  
pp. 2089-2103 ◽  
Author(s):  
T. Wutzler ◽  
M. Reichstein
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Balance Model ◽  
Levels Of Abstraction ◽  
Substrate Quality ◽  
Substrate Limitation ◽  
Energy Limitation ◽  
Bare Fallow ◽  
Different Levels

Abstract. Interactions between different qualities of soil organic matter (SOM) affecting their turnover are rarely represented in models. In this study, we propose three mathematical strategies at different levels of abstraction to represent those interactions. By implementing these strategies into the Introductory Carbon Balance Model (ICBM) and applying them to several scenarios of litter input, we show that the different levels of abstraction are applicable at different timescales. We present a simple one-parameter equation of substrate limitation that can straightforwardly be implemented into other models of SOM dynamics at decadal timescale. The study demonstrates how substrate quality interactions can explain patterns of priming effects, accelerate turnover in FACE experiments, and the slowdown of decomposition in long-term bare fallow experiments as an effect of energy limitation of microbial biomass. The mechanisms of those interactions need to be further scrutinized empirically for a more complete understanding. Overall, substrate quality interactions contribute to both understanding and quantitatively modelling SOM dynamics.

scholarly journals Intake, digestibility, and ruminal parameters of Nellore bulls supplemented with increasing levels of crude glycerin in Brachiaria Brizantha pastures

2017 ◽  
Vol 18 (4) ◽  
pp. 518-529 ◽  
Author(s):  
Adriano Jorge Possamai ◽  
Joanis Tilemahos Zervoudakis ◽  
Luciana Keiko Hatamoto-Zervoudakis ◽  
Lucien Bissi da Freiria ◽  
Pedro Ivo José Lopes da Rosa Silva ◽  
...  
Keyword(s):  
Organic Matter ◽  
Latin Square ◽  
Serum Glucose ◽  
Nutrient Digestibility ◽  
Crude Glycerin ◽  
Brachiaria Brizantha ◽  
Mineral Mixture ◽  
Organic Matter Digestibility ◽  
Four Levels ◽  
Different Levels

SUMMARY We evaluated the effects of increasing levels of crude glycerin in multiple supplements for grazing beef cattle on intake, nutrient digestibility, pH, ruminal ammoniacal nitrogen, and serum glucose. Five Nellore steers (initial BW of 480 kg [SD 15]), grazing a tropical pasture, were used in a 5 × 5 Latin square design. The treatments used were control (no supplementation; only a mineral mixture ad libitum) and four levels of crude glycerin (0, 80, 160, 240 g/kg of supplements). Supplementation type had no impact (P > 0.05) on pH at 0 and 4 h after supplementation. Animals supplemented with different levels of crude glycerin showed higher N-NH3 values (P < 0.05) at 4 h after supplementation. Crude glycerin supplementation did not reduce pasture intake (P > 0.05), increasing dry matter intake (P > 0.05) due to increased organic matter digestibility (P > 0.05). Supplementation of 4 kg/animal with crude glycerin (240 g/kg supplement) did not reduce pasture intake and organic matter digestibility.

scholarly journals Growth of Three Rice (Oryza sativaL.) Cultivars under Upland Conditions with Different Levels of Water Supply

2006 ◽  
Vol 9 (4) ◽  
pp. 422-434 ◽  
Author(s):  
Yoichiro Kato ◽  
Akihiko Kamoshita ◽  
Junko Yamagishi ◽  
Jun Abe
Keyword(s):  
Water Supply ◽  
Upland Conditions ◽  
Different Levels

scholarly journals Computational modelling methods for assessing the risks from lead in drinking water

2010 ◽  
Vol 8 (3) ◽  
pp. 532-542 ◽  
Author(s):  
Colin R. Hayes
Keyword(s):  
Risk Assessment ◽  
At Risk ◽  
Drinking Water ◽  
Water Supply ◽  
Computational Modelling ◽  
Worst Case ◽  
Lead Pipe ◽  
Modelling Methods ◽  
Very High ◽  
Different Levels

Computational modelling methods have been used to predict the risks from lead in drinking water across a simulated supply zone, for a range of plumbosolvency conditions and a range of extents of occurrence of houses having a lead pipe, on the basis of five risk benchmarking methods. For the worst case modelled (very high plumbosolvency and 90% houses with a lead pipe) the percentage of houses at risk in the simulated zone ranged from 34.1 to 73.3%. In contrast, for a simulated phosphate-treated zone and 10% houses with a lead pipe, the percentage of houses at risk in the simulated zone ranged from 0 to 0.4%. Methods are proposed for using computational modelling for different levels of risk assessment, for both water supply zones and individual houses. These risk assessment methods will inform policy, help to set improvement priorities and facilitate a better understanding of corrective options.

Effects of shelter, exposure and level of feeding over winter on the productivity of Welsh Mountain ewes and lambs

1973 ◽  
Vol 17 (1) ◽  
pp. 21-32 ◽  
Author(s):  
W. I. Robinson ◽  
W. Brown ◽  
I. A. M. Lucas
Keyword(s):  
Weight Loss ◽  
Body Weight ◽  
Organic Matter ◽  
Live Weight ◽  
Outdoor Exposure ◽  
Wool Growth ◽  
Digestible Organic Matter ◽  
Maintain Body Weight ◽  
Fourth Experiment ◽  
Different Levels

SUMMARYPregnant Welsh Mountain ewes were kept over winter on a hill. All were penned individually, either in a shed or out of doors. In Experiments 1 and 2 different levels of digestible organic matter (DOM) were given in each environment and in Experiment 3 only a single level was offered. In Experiment 2 all ewes were grazed together after lambing; in Experiment 3 some from each treatment were moved to a shed after lambing and their milk yields recorded between 10 and 15 days later.In a fourth experiment on low land, pregnant ewes were either housed or kept in an exposed or a sheltered paddock. All were grazed together after lambing.The results indicated that the requirement of indoors penned sheep to maintain body weight and produce a single lamb is 9·5 g DOM/kg live weight per 24 hr at 16 weeks pre-partum, rising to 15·0 g DOM/kg live weight per 24 hr at 1 week pre-partum. A 10% weight loss during pregnancy would be expected in ewes receiving 75 to 80 % of these requirements. Low intakes during pregnancy reduced wool growth and lamb birth weights.Outdoor exposure reduced pre-partum ewe weight by about 1·5 kg, and so was equivalent to a 10% reduction in daily DOM intake. The magnitude of this effect was not changed significantly by level of feeding. Exposure did not affect wool growth and its influence on lamb birth weight and growth was variable.

Sign in / Sign up

Export Citation Format

Share Document