Interannual variations of above-ground biomass and nutritional quality of Mediterranean grasslands in Western Spain over a 20-year period

2008 ◽  
Vol 59 (8) ◽  
pp. 769 ◽  
Author(s):  
B. R. Vázquez-de-Aldana ◽  
A. García-Ciudad ◽  
B. García-Criado
Keyword(s):  
Nutritional Quality ◽  
Fibre Content ◽  
Annual Precipitation ◽  
Total Biomass ◽  
Interannual Variations ◽  
Above Ground Biomass ◽  
Neutral Detergent Fibre ◽  
Acid Detergent Fibre ◽  
Western Spain

The ‘dehesas’ are savannah-like semi-arid grasslands typical of western Spain, which are subject to strong inter-annual variations in biomass production. Over a 20-year period, from 1986 to 2005, above-ground biomass and the nutritional quality of these grasslands in the province of Salamanca (western Spain) were evaluated to determine the relationships between interannual variations in grassland parameters and climate variables (precipitation and temperature). Herbage samples were collected from several sites, along a topographic gradient that differentiated two types of herbaceous communities on the upper and lower part of the slope. Nutritional quality was assessed on the basis of protein, acid detergent fibre, neutral detergent fibre, lignin and digestibility. On both the upper and lower zones, total biomass and biomass of grasses were correlated with annual precipitation calculated from the previous October to the current June. Biomass of legumes and forbs, on the upper zones, was correlated with spring precipitation. Step-wise multiple regression analysis provided different models for grasses, legumes, forbs, and total biomass for the upper and lower zones. Protein concentration was negatively correlated with annual precipitation in both zones of the slope. The number of days in spring with precipitation (≥1 mm or ≥10 mm) was a good predictor of the lignin content and digestibility in both zones of the slope, and of the acid detergent fibre content on the upper zones and the neutral detergent fibre content on the lower zones.

scholarly journals Yields, plant characteristics, total N and fibre composition of timothy cultivars grown at two latitudes

1996 ◽  
Vol 5 (4) ◽  
pp. 461-473 ◽  
Author(s):  
H. Tapani Kunelius ◽  
Pertti Pärssinen ◽  
Seppo K. Pullli
Keyword(s):  
Nutritional Quality ◽  
Prince Edward Island ◽  
Dry Matter ◽  
Phleum Pratense ◽  
Yield Stability ◽  
Total N ◽  
Acid Detergent Fibre ◽  
Plant Characteristics ◽  
Phleum Pratense L

Timothy (Phleum pratense L.) cultivars of southern (45°N) and northern (≥60°N) origin were grown in Charlottetown, Prince Edward Island, Canada (46° N) and Jokioinen, Finland (61° N) in two years. Timothy was harvested twice a season and nitrogen applied at 100 or 150 kg/ha. Dry matter yields were higher in Charlottetown than in Jokioinen and northern cultivars outyielded southern cultivars. Nitrogen at 150 kg/ha increased total yields an average of 1.4 t/ha over the 100 kg N/ha rate. The stems and panicles of timothy were longer in Charlottetown. Northern cultivars had longer panicles. The leaf content of cultivars ranged from 139 to 230 g/kg. Northern cultivars had greater N concentrations (22.1 g/kg) in cut 2 than southern timothies (19.7 g/kg). Concentrations of neutral detergent fibre (NDF) and acid detergent fibre (ADF) in cut 1 were lower in Jokioinen, In conclusion, northern cultivars performed well in Charlottetown but there were differences in yield stability among cultivars. Nutritional quality of timothy cultivars varied among the sites and the significance of differences in NDF and ADF in relation to animal performance require further study.

scholarly journals Influence of different grazing intensity on above-ground biomass in Mongolian rangeland

2019 ◽  
pp. 29-38
Author(s):  
Lkhagvajav Otgontuya ◽  
Asrun Elmarsdottir ◽  
Namdag Lkhagvajav ◽  
Chimed Munkhbat
Keyword(s):  
Block Design ◽  
Grazing Intensity ◽  
Total Biomass ◽  
Above Ground Biomass ◽  
Land Usage ◽  
Ground Biomass ◽  
Cutting Frequency ◽  
Cutting Experiment ◽  
Cutting Height

In the last two decades, the quality of Mongolian rangeland has degraded primarily owing to overgrazing and climate change. This has government challenged to improve land usage and gather information about the tolerance of the rangeland. The aim of this research was to examine the effect of cutting frequency (four, three, two and one), cutting height (0 and 3 cm) and duration of cutting on above-ground biomass at different degradation levels of Fescue-forbs rangeland. Three sites were selected with different degradation levels; slightly, moderately and heavily degraded. The cutting experiment was randomized with complete block design with five replications. Samplings were carried out in 2006, 2007 and 2008. In 2009, all the plots of rangelands were cut at the same time in August and at 0 cm height and the results were analyzed. The results showed that total biomass was influenced by cutting frequency, cutting height and the duration of cutting. Biomass decreased considerably with increasing cutting frequency in most cases when cutting height was 0 cm but small changes were noticed when cutting height was 3 cm. The biomass decreased by 30-54% when cut four times a year at 0 cm in slightly- and moderately-degraded sites. Year of duration influenced biomass significantly at slightly- and heavily degraded sites.

Leaf nutritional quality as a predictor of primate biomass: further evidence of an ecological anomaly within prosimian communities in Madagascar

2012 ◽  
Vol 28 (2) ◽  
pp. 141-151 ◽  
Author(s):  
Bruno Simmen ◽  
Laurent Tarnaud ◽  
Annette Hladik
Keyword(s):  
Nutritional Quality ◽  
Species Abundance ◽  
Basal Area ◽  
Total Biomass ◽  
Leaf Production ◽  
Primate Communities ◽  
Chemical Index ◽  
Closed Canopy ◽  
Primate Biomass

Abstract:The correlation between the biomass of forest primates and a chemical index of the average nutritional quality of leaves in tropical forests has been repeatedly documented since 1990. We tested the role played by protein : fibre on lemur biomass in a gallery forest in southern Madagascar. Plant species abundance was determined based on transect censuses. We calculated an average ratio of protein-to-fibre in leaves and an abundance-weighted ratio, i.e. the mean weighted by the basal area of tree species, to be compared with the figures available for other forest ecosystems in Madagascar and a number of anthropoid habitats. Lemur densities were evaluated through compilation of previous studies made from prior to 1975 and up until 2011 based on strip censuses and/or identification of all groups supplemented with new censuses. A high mean ratio of protein to fibre (> 0.4) supports high folivore biomass at 390 kg km−2 (reaching 630 kg km−2 in the closed-canopy forest area) compared with primate communities in other Malagasy forests (protein : fibre: < 0.5; folivore biomass: < 440 kg km−2), as predicted. However, the data corroborate the finding that the total biomass of lemur communities as well as the biomass of folivorous lemur species are low compared with those of African and Asian primate communities for a given protein : fibre ratio. Tree diversity and leaf production do not consistently explain this pattern. In contrast, the extinction of large folivorous lemurs during the past two millennia presumably allowed too little time for smaller-sized species to evolve equally effective morphological and physiological specializations for processing a large range of fibrous foods.

Chemical and physical characteristics of grains related to variability in energy and amino acid availabilityin ruminants: a review

1999 ◽  
Vol 50 (5) ◽  
pp. 651 ◽  
Author(s):  
Samantha L. van Barneveld
Keyword(s):  
Nutritional Quality ◽  
Physical Characteristics ◽  
Starch Granules ◽  
Protein Matrix ◽  
Starch Fermentation ◽  
Degradation Rates ◽  
Acid Detergent Fibre ◽  
Ruminant Animals ◽  
The Subject

This paper reviews the carbohydrate, protein, lipid, anti-nutritional, and physical characteristics ofgrains that determine the variability in their nutritional quality for ruminant animals. The amount, rate, and extent of starch fermentation in the rumen have been the subject of many studies, with large variation found between and within grain species. Electron microscopy scanning techniques have shown that the protein matrix limits the microbial colonisation of starch granules in some grain species, whereas in others it may be the structural carbohydrates that affect colonisation. The composition of the different fibre fractions of grains and their interaction with non-fibre carbohydrates requires investigation, since it has been shown that non-starchpolysaccharides, including neutral detergent fibre and acid detergent fibre, may not be specific enough to predict animal response to grain. Fermentation patterns of the non-starch polysaccharide components of legumes are also poorly understood and hence require further investigation. Different varieties of grain and different seasonal conditions show variation in the protein fractions of the kernel. Since these fractions display different solubility and degradation rates in the rumen, rumen solubility values cannot be generalised for grains. The variability in solubility caused by rumen flow rate and pH is a further complication. Finally, the lipid content of grains varies greatly, with high-oil grains potentially contributing to the energy level of the diet, but possibly negatively affecting rumen fermentation. Due to the degree of variability of characteristics discussed in this review, it is clear that the nutritional quality of grains cannot be assessed in a single rapid assay.

Food procurement in English-language Canadian public schools: Opportunities and challenges

2019 ◽  
Vol 6 (1) ◽  
pp. 75-99
Author(s):  
Shawna Holmes
Keyword(s):  
Public Schools ◽  
Food Environment ◽  
Nutritional Quality ◽  
English Language ◽  
Nutrient Content ◽  
Food Environments ◽  
School Food ◽  
Provincial Level ◽  
School Food Environment

This paper examines the changes to procurement for school food environments in Canada as a response to changes to nutrition regulations at the provincial level. Interviews with those working in school food environments across Canada revealed how changes to the nutrition requirements of foods and beverages sold in schools presented opportunities to not only improve the nutrient content of the items made available in school food environments, but also to include local producers and/or school gardens in procuring for the school food environment. At the same time, some schools struggle to procure nutritionally compliant foods due to increased costs associated with transporting produce to rural, remote, or northern communities as well as logistic difficulties like spoilage. Although the nutrition regulations have facilitated improvements to food environments in some schools, others require more support to improve the overall nutritional quality of the foods and beverages available to students at school.

Fluctuations of Annual Precipitation and Water Resources Quality in Ukraine

2016 ◽  
Vol 10 (4s) ◽  
pp. 621-629
Author(s):  
Valentina Pidlisnyuk ◽  
◽  
John Harrington JR ◽  
Yulia Melnyk ◽  
Yuliya Vystavna ◽  
...  
Keyword(s):  
Water Resources ◽  
Surface Waters ◽  
Precipitation Amount ◽  
Ion Concentration ◽  
Annual Precipitation ◽  
Resource Quality ◽  
Phosphate Ion ◽  
Regional Trends

The article focuses on examining the influence of fluctuations in annual precipitation amount on the quality of surface waters. Water quality was estimated with data on BOD, COD and phosphate–ion concentration within five selected regions of Ukraine. Analysis of the precipitation data (1991 – 2010) showed different regional trends. Using the statistics, determination of the interconnection between precipitation amount and water resources quality were done. The obtained regularities and associated uncertainties can be used for prediction of changes in water resource quality and as a guide for future adaptation to possible climate change.

IMPROVING THE NUTRITIONAL QUALITY OF FODDER YEASTS BY ADDING MINERALS

2016 ◽  
Vol 15 (5) ◽  
pp. 1009-1017
Author(s):  
Cristina-Gabriela Grigoras ◽  
Andrei I. Simion ◽  
Livia Manea ◽  
Lidia Favier-Teodorescu ◽  
Lucian Gavrila
Keyword(s):  
Nutritional Quality
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