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A set of structural criteria to differentiate among types of a heterogeneous woodland landscape that are shaped by goat and
cattle grazing was studied in northern Israel. The landscape was described with relation to the “human scale” of the observer,
by mapping the dimensions, basic shapes, and distribution of gaps between individual plants on sites with various grazing
management systems. The shapes of the trees and the bushes were drawn in situ and the ratio between plant height and the width
of the adjacent open space was measured in order to define the various structural profiles of the vegetation. All the structural
criteria clearly and significantly differentiated among grazing systems that created closed (no grazing), half-open (cattle
and modern goat grazing) and open (traditional goat grazing) landscapes. The diversity of plant shapes was highest under the
cattle and modern goat grazing management systems. In the ungrazed treatment, more than 60% of the gaps were defined as ‘inaccessible’
compared with only 10–15% under cattle grazing and modern goat grazing. The diversity of gap proportions was high, but their
absolute number was low. Under traditional heavy goat grazing, there were only wide and open gaps. Under cattle grazing and
modern goat-grazing management systems, a relatively large number of wide and open gaps were found, with small numbers of
narrow and closed gaps. Overall, the various grazing systems were differentiated most clearly according to their transparency,
accessibility, height of Quercus calliprinos, and gap distribution. We conclude that structural criteria provide an efficient and objective methodology for evaluating
the effects of grazing on different components of Mediterranean woodland mosaic landscapes.
Nomenclature follows Feinbrun-Dothan and Danin (1991) 相似文献
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Zalmen Henkin Avi Perevolotsky Arik Rosenfeld Arieh Brosh Fred Provenza Nissim Silanikove 《Livestock Science》2009,126(1-3):245-251
The aim of the present study was to determine the effect of polyethylene glycol (PEG) supplementation on grazing behaviour of beef cattle and on utilization of the woody components of a Mediterranean shrubland. Two experiments were conducted on two different sites in Northern Israel, Ramat Hanadiv (RH) and Hatal. On each site, the study area was divided into two paddocks, in one cattle were supplemented with 50 g PEG day− 1 per cow, while the other served as a control, with no PEG supplementation. In RH site the cows had free access to Prolix and in Hatal to poultry litter, both serving as a nitrogen supplement during the experiment. In the RH site, the consumption of Pistacia lentiscus, a shrub whose leaves contain high concentration of tannins, was found higher (P = 0.001) in the PEG group diet than in the control group. In Hatal site PEG increased foraging time by 18%, daily foraging distance by 15% and reduced the use of supplementary feed (poultry litter) by 20%. However, PEG did not affect the average cow body weight or water consumption on either site. It is concluded that PEG influences grazing behaviour of beef cattle on shrubby rangeland and increases the use of woody species with high tannin concentrations. 相似文献
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A grazing trial was conducted over 10 years to determine the feasibility of using beef cattle to graze a Mediterranean oak scrub forest that for millennia had been grazed by mixed herds of domestic ruminants dominated by goats. After initial thinning of the woody vegetation, two large paddocks were stocked with cross-bred beef cows, one at a relatively heavy stocking rate (0.67 cows ha–1) and the other at a lighter rate (0.48 cows ha–1). During the summer and autumn, the herds were given free access to supplementary feed composed mainly of poultry litter. Despite the higher grazing pressure, mean weaning weight per cow in the heavily grazed paddock was similar to that in the moderately grazed paddock and required a similar investment of supplementary feed per kg of weaned liveweight. Consequently, weaned calf weight production per unit area was higher under the heavier grazing regimen. A shift in calving season from autumn to spring improved herd performance. In comparison with beef cattle husbandry on herbaceous range in the region, animal performance with autumn calving was inferior even though supplementation levels were similar; with spring calving, animal performance was similar on both range types, but much less supplementation was required on the herbaceous range. An open park-like landscape was maintained especially under heavy grazing where, after the initial thinning, the regrowth from the bases of the oak trees was browsed down to 0.5 m. Herbaceous cover increased steadily over the years under both heavy and moderate stocking rates, but more so in the heavily grazed paddock. Whereas a large degree of control of the woody scrub was attained by heavy cattle grazing, maintaining performance of moderately heavy cross-bred cows involved relatively intensive supplementary feeding. In addition, for sustained management of such systems, recurrent technological intervention was necessary to prevent excessive encroachment of the dwarf-shrub vegetation. However, it is evident that with further improvement in herd management, especially by development of hardier, better adapted animals, it is possible to improve feasibility of beef cattle husbandry under such Mediterranean woodland conditions.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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Intensive chronic plasmapheresis in dogs 总被引：1，自引：0，他引：1
N Orentreich S Ettinger R J Tashjian E Stanislowski R Henkin 《American journal of veterinary research》1968,29(10):1929-1933
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Brosh A Henkin Z Ungar ED Dolev A Orlov A Yehuda Y Aharoni Y 《Journal of animal science》2006,84(7):1951-1967
This study with grazing beef cows on the range was designed to explore the possibility of determining incremental energy expenditure (EE) in standing, traveling, and grazing relative to that in lying down, by means of continuous monitoring of EE, location, and activity by the heart-rate method, with Global Positioning System (GPS) collars, and by motion sensors in the GPS collars, respectively. Cows were observed on Mediterranean foothill rangeland covered with herbaceous vegetation through 4 seasons of the year. There were 2 stocking rate treatments, and 14 statistical models were evaluated, including one that was a stepwise model. Total daily EE (TEE) was affected by many interdependent factors apart from activity, including season, stocking rate, herbage quality, standing biomass, and reproductive state of the cow. Each model included all activity variables, plus some of the other factors. Across seasons and treatments TEE, in kJ/(kg of BW(0.75) . d), ranged from 469 in densely stocked, nonlactating cows in June to 1,092 in sparsely stocked, lactating cows in April. The cows' daily vertical and horizontal movements ranged from 75 to 174 m and from 1.5 to 4.2 km, respectively. Within a day, time spent traveling (without grazing) ranged from 0 to 32 min, and grazing time ranged from 4.4 to 12.1 h. Cows spent less time grazing (P < 0.001) in the summer, when herbage quality was low, than in winter and spring. Relative to the baseline EE while lying down, the daily increment incurred by grazing ranged from 13 to 48 kJ/(kg of BW(0.75) . d), and that incurred by grazing, standing, and traveling combined ranged from 38 to 74 kJ/(kg of BW(0.75) . d) or 5.8 to 11.4% of TEE. In conclusion, the estimates of activity costs yielded by 11 of the models were similar to one another, whereas those yielded by the stepwise model and the remaining 2 models were 20% smaller. The cost of grazing activity was estimated to be 6.14 J/(kg of BW(0.75) . m), and that of locomotion during grazing was 6.07 J/(kg of BW(0.75) . m), which agree with values obtained for animals and humans by means of a treadmill. The experimental and statistical approach tested here yielded fairly reliable estimations of energy costs of activities in grazing cows. 相似文献
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Rui Zhang Yanfu Bai Tao Zhang Zalmen Henkin A. Allan Degen Tianhua Jia Cancan Guo Ruijun Long Zhanhuan Shang 《Strength and Conditioning Journal》2019,72(2):396-404
Soil carbon and sugars play key roles in carbon (C) cycling in grassland ecosystems. However, little is known about their changes in quantity and composition in degraded alpine meadows in the Tibetan plateau. We compared vegetation C density, soil organic carbon (SOC) density, and soil sugars in nondegraded (ND), degraded (DA; following artificial restoration), and extremely degraded (ED) grasslands and analyzed the relation among these parameters by redundancy analysis (RDA) and structural equation models (SEMs). Belowground biomass, soil microbial biomass C, soil microbial biomass nitrogen (N), belowground biomass C density, SOC density, and soil sugars were lower in DA and ED grasslands than in ND grasslands. In addition, the ratio of belowground biomass to aboveground biomass (BAR) decreased with an increase in degradation. The ratio of belowground biomass to aboveground biomass was identified as the main indirect driving force of ecosystem C density by affecting total vegetation C and SOC densities. Soil dissolved organic carbon (DOC), microbial biomass carbon (SMBC), neutral sugars (NS), and total nitrogen (TN) were identified as main direct driving forces. The ratio of belowground biomass to aboveground biomass altered DOC, SMBC, NS, and TN and, consequently, was the primary driving force for the alpine meadows’ ecosystem C density. It was concluded that land management in alpine meadows should include practices that maintain a relatively high BAR in order to curb degradation and increase ecosystem C density. 相似文献
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Z. Henkin E. D. Ungar L. Dvash A. Perevolotsky Y. Yehuda M. Sternberg H. Voet S. Y. Landau 《Grass and Forage Science》2011,66(4):516-525
The main objective of this study was to determine to what extent grazing pressure and timing modulate the seasonal progression of herbage quality in hilly Mediterranean grassland systems. The study was conducted during six consecutive years between 2003 and 2008 at the Karei Deshe experimental farm, in eastern Galilee, Israel, dominated by rich hemicryptophytic grassland. Treatments included two different grazing intensities, heavy and moderate, with 1·1 and 0·55 cows ha?1, respectively, and management that included a continuous and a seasonal stocking system that was divided at both intensities into early and late grazing. Herbage samples were analysed for digestibility, crude protein, neutral detergent fibre and acid detergent fibre contents. Significant differences in herbage quality were found between seasons and years. Herbage quality was significantly higher in paddocks grazed continuously or early in the season. Herbage quality increased with increasing grazing intensity as younger herbage and continued re‐growth were maintained during the green season. The greater difference between herbage qualities was found at the peak of the growing season. The significant differences found in herbage quality emphasize the importance of the decision‐making process aimed at improving cattle grazing management in Mediterranean rangelands and its consequences for the sustainability of the system. 相似文献
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