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Forage patch use by grazing herbivores in a South African grazing ecosystem

100%

Venter J. A., Nabe-Nielsen J., Prins H. H. T., Slotow R.

Acta Theriologica

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2014

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tom 59

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nr 3

Understanding how different herbivores make forage patch use choices explains how they maintain an adequate nutritional status, which is important for effective conservation management of grazing ecosystems. Using telemetry data, we investigated nonruminant zebra (Equus burchelli) and ruminant red hartebeest (Alcelaphus buselaphus subspecies camaa), use of burnt patches in a landscape mosaic of nutrient-poor, old grassland interspersed with young, recently burnt, nutrient-rich grass patches. The Mkambati Nature Reserve landscape on the east coast of South Africa provided large grazers with a challenge in finding and using appropriate patches in which to forage to meet their nutritional requirements. In Mkambati, grassland fires, mostly ignited by poachers, induce regrowth of young nutrient-rich grass, which subsequently attract grazers. We tested if the study animals foraged more in burnt patches than in the unburned grassland and whether burnt patch use was related to the distance to the previously visited burnt patch, burnt patch size, burnt patch age, and distance to areas with high poaching risk using MANOVA. In general, zebra moved faster than red hartebeest, and both species moved faster in unburnt grassland than in burnt patches. Red hartebeest and zebra patch selection were influenced by interpatch distance, patch age, patch size, and poaching risk. A limited set of intrinsic traits, i.e., body mass, digestion strategy, and muzzle width, yielded different patch use rules for the two species. Large ungulates patch use behaviour varied among species and across conditions and was influenced by anthropogenic impacts such as poaching and changed fire regimes. This could potentially affect biodiversity negatively and needs to be factored into management of conservation areas.

2

The effect of grazing on the population of Plantago coronopus L.

100%

Sotek Z.

Folia Universitatis Agriculturae Stetinensis. Agricultura

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1999

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tom 80

3

Effect of long-term abandonment and spring grazing on floristic and functional composition of dry grasslands in a Central Apennine farmland

86%

Catorci A., Casaretti S., Gatti R.

Polish Journal of Ecology

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2013

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tom 61

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nr 3

Semi-natural dry grasslands host some of the most valuable habitats in Europe, due to their biodiversity heritage. Nevertheless, a strong decline in their extension, due to the cessation of traditional management, has been observed in the last decades. The aim of the study was to assess plant community changes due to abandonment and the effect of spring grazing in sub-Mediterranean dry grasslands, focusing on the plant functional traits involved in this turnover. The study area is located in the central Apennines (Italy), where grasslands were grazed by sheep in late winter and spring until 1980 and are nowadays abandoned. Relevés sampled (using the Braun-Blanquet method) in different years, namely in 1976–1980 (grazed pasture) and again in 2010 (abandoned pasture) were compared. Results indicated that abandonment leads to the increase of species richness. Traits and strategies indicator sets were: therophyte for the grazed pasture; geophytes, flower palatability, early flowering strategy, clonal ability and presence of storage organs for the abandoned ones. Traits related to low levels of stress (tolerance strategies) are heavily reduced in grazed systems, and thus the functional composition of plant community is mostly characterised by traits promoting avoidance strategies. In abandoned conditions a higher number of species can co-exist thanks to the micro-scale variation of soil features and niche diversification. The research findings also revealed grazing timing as a key factor for understanding changes of plant functional trait patterns and spring grazing as a threat for orchid species.

4

Plant functional trait response to habitat change and grazing in a semiarid grassland: unravelling species turnover and intraspecific variation effects

86%

Zhang J., Zuo X., Lv P., Zhao S., Zhao X.

Polish Journal of Ecology

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2019

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tom 67

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nr 1

Plant community assembly is determined by species turnover and intraspecific trait variations (ITV) controlled by environment changes. However, little is known about how species turnover and ITV affect the responses of plant community to habitat changes and grazing disturbance in semiarid grasslands. Here, we measured five functional plant traits in four typical grassland habitats under fencing and grazing disturbance in a semiarid grassland, Northern China, including plant height, specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen content (LNC) and leaf carbon: nitrogen ratio (C:N). We also calculated the community weighted means (CWM) and non-weighted means (CM) of all traits and examined the relative roles of species turnover and ITV in affecting the responses of community traits to habitat changes and grazing disturbance. Our results showed that the CWM and CM values of five functional traits differed with grassland habitat changes. As compared to other grasslands, the Stipa steppe had the higher plant height, the sandy grassland had the higher SLA and lower LDMC, and the meadow had the lower LNC and higher C:N. Grazing decreased plant height across grassland habitats, as well as decreased SLA and increased LDMC in meadow. The responses of all community-level traits to habitat changes were driven by species turnover, while the responses of phenotypic traits (height, SLA and LDMC) to grazing were determined by both species turnover and ITV. So, we argue that ITV should be considered when understanding plant community assembly under grazing disturbance regime in semiarid grasslands.

5

Constitutive and induced chemical defenses against insect grazing on leaves of forest understory shrubs

86%

Zmuda M., Karolewski P., Giertych M. J., Oleksyn J.

Acta Physiologiae Plantarum

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2007

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tom 29

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nr 1 Suppl.

6

Rotational and continuous grazing of heifers in the upland of the Jizerske Hory Mountains

86%

Pavlu V., Gaisler J., Auf D., Mrkvicka J., Santrucek J., Vesela M.

Zeszyty Naukowe Akademii Rolniczej w Krakowie. Sesja Naukowa

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2000

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tom 73

7

The response of small mammal communities to cattle grazing on a coastal meadow

86%

Schmidt N. M., Olsen H.

Polish Journal of Ecology

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2003

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tom 51

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nr 1

The response of small mammals to cattle grazing on a coastal meadow with three different grazing intensities was evaluated. Grazed areas tended to hold fewer small mammals than the ungrazed control area, though the variation was high. The negative effect of grazing increased with grazing intensity. Small mammals were caught almost exclusively in patches of high, dense vegetation, and it is suggested that the negative effect of grazing results from the reduced number of such patches. Grazing also affected small mammal species richness, where richness was generally lower in the area of high grazing intensity than in areas with low grazing intensity or without grazing.

8

Plant traits response to grazing exclusion by fencing assessed via multiple classification approach: a case from a subalpine meadow

72%

Li W. J., Liu S. S., Li J. H., Zhang R. L., Rang K. Z. C., Zhou H. K., Yao B. Q., Wang J. F.

Polish Journal of Ecology

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2019

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tom 67

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nr 1

Using multiple classification approach to examine plant traits response to grazing and fencing (as without access to grazing) is rare. Here we used multiple classification approach to examine plant diversity, productivity and species traits response to grazing and fencing over a three-year period on the eastern part of the Qing-Hai Tibetan Plateau. The results showed that most common species response to the fence was poorly noticeable. The fencing meadows compared to those under long-term free grazing are characterized by significantly higher total species richness, but species richness declined with sampling years gradually, regardless of grazing or fencing. The correlation showed that species richness was negatively associated with mean annual temperature significantly, suggesting that abiotic factors (e.g. annual temperature) could also play important roles in driving species richness in this subalpine meadow. Total aboveground biomass was not associated with mean annual temperature and rainfall. The fencing meadow demonstrated higher community aboveground biomass relative to the grazing ones, especially the abundance of legume and graminoids increased, while the proportions of sedge decreased, suggested that grazing disturbance favours the increase of reproductive success of sedge (e.g. Kobresia humilis) in this subalpine meadow. Growth form-based analyses combined with canopy height categories should be recommended to reveal general rules and mechanisms relating to grazing.

9

Spatial heterogeneity of soil seed banks in sandy grasslands under fencing and grazing in Horqin sandland, Northern China

72%

Zuo X., Zhao X., Zhao H., Zhang T., Wang S., Knops J., Kochsiek A.

Polish Journal of Ecology

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2013

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tom 61

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nr 2

Understanding composition, structure and spatial heterogeneity in soil seed banks is important for the management of grassland ecosystem. Although the effect of fencing and grazing on vegetation composition is widely known, information on species composition, seed density and spatial heterogeneity of soil seed banks in sandy grasslands under fencing and grazing is still lacking. We measured the species composition and seed density of soil seed banks in fenced grassland, grazed grassland and grazed shrubby grassland in Horqin Sand Land, Northern China. By applying the geostatistical methods, we assessed how fencing and grazing affected spatial heterogeneity of soil seed banks in sandy grasslands. Total seed density and species richness in soil seed banks were lower in fenced grassland than in either grazed grassland or grazed shrubby grassland. Seed density and species richness of annual species in soil seed banks were also lower in fenced grassland than in either grazed grassland or grazed shrubby grassland, while those of perennial species showed a reverse trend. The analysis of spatial autocorrelation ranges, fractal dimensions and distribution pattern maps from geostatistical methods showed that spatial heterogeneity of seed density and species richness in soil seed banks were also lower in fenced grassland than in either grazed grassland or grazed shrubby grassland. Continuous fencing increases the seed density and species richness of perennial species in soil seed banks, as well as results in a decrease in spatial heterogeneity of seed density and species richness in soil seed banks. So, continuous fencing should be considered to restore the degraded sandy grasslands in management of semiarid grassland ecosystems.

10

Distribution of the nurse species Pycnophyllum molle J.Remy and P. weberbaueri Muschl. in the Andean dry puna (Arequipa district - Southern Peru): role of topographic-soil variability and disturbance regime

72%

Catorci A., Piermarteri K., Tardella F. M.

Polish Journal of Ecology

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2014

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tom 62

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nr 2

The dry Puna is the widest pastoral ecosystem of the tropical alpine Andes, characterized by harsh environmental conditions (long and intense drought stress periods and unfertile soils) and grazed by wild and domestic camelids. In these conditions, facilitation is of key importance in plant diversity conservation. Indeed, facilitation is a positive plant-plant interaction by which the so called nurse species provide environmental amelioration of harsh conditions and/or refuge to other plants (beneficiary species), which otherwise might fail to establish. The research aims were to understand which ecological variables affect the distribution of the potential nurse cushion species Pycnophyllum molle J. Rémy and P. weberbaueri Muschl., and if these species are affected by grazing disturbance. The study area (4000–4900 m a.s.l.) is located in the southern Peruvian Andes. Data of species cover, topographic and soil features, besides type of disturbance were collected along transects. We used canonical redundancy analysis to understand the relations between the cover of the two Pycnophyllum species and the above mentioned constraining variables. Results indicate that both the Pycnophyllum species grow on sandy loam, moderately acid soils, with low organic matter and very poor nitrogen content, and avoid high disturbance intensities. P. molle is more sensitive than P. weberbaueri to disturbance, and grows on relatively more fertile soils, also at higher altitudes and on steeper slopes characterized by greater rockiness.

11

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Dependence between temperature and clearance rate of Balanion comatum Wulff

72%

Rychert K.

Oceanologia

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2011

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tom 53

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nr 2

The dependence between temperature and clearance rate of the ciliate Balanion comatum Wulff 1919 was assessed in the coastal zone of the southern Baltic Sea. Five in situ experiments were carried out with the use of wheat starch as a surrogate of food particles. The clearance rate rose from 1.4 to 7.0 μl cell−1 h−1 with a temperature rise from 8 to 19◦C. B. comatum preferred particles of size 1.9–4.4 μm, and the clearance rates calculated for the preferred particles were consistently higher than those measured for the whole range of particles ingested (Wilcoxon’s signed rank test, p = 0.04). The exponential dependence between temperature and clearance rates for preferred particles was statistically significant (R2 = 0.86, p = 0.02) and enabled the Q10 coefficient to be calculated. This amounted to 2.9 and lay within the range of typical values. The linear dependence (also drawn for preferred particles) demonstrated a higher significance (R2 = 0.91, p = 0.02), indicating the linear dynamics of the process.

12

Benefits of low-intensive grazing: co-occurrence of umbelliferous plant (Hladnikia pastinacifolia Rchb.) and opilionid species (Phalangium opilio. L) in dry, calcareous grassland

72%

Sajna N., Kusar P., Slana Novak L., Novak T.

Polish Journal of Ecology

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2011

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tom 59

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nr 4

The impact of grazing has been discussed in many organisms, and it has been shown that it has considerable influence on the structural variation of vegetation, resulting in its tussocky appearance. Such spatial heterogeneity results in plants formations that facilitate other species by providing safe sites against predation and physical stress. On the Trnovski gozd plateau in western Slovenia, a secondary habitat of the rare, monotypic endemic umbelliferous species, Hladnikia pastinacifolia, was colonized by a relatively isolated population of the wide spread opilionid species, Phalangium opilio. We hypothesized that in this stony pasture, the impact of the structurally heterogenous vegetation that results from low-intensity grazing benefits both species on hot summer days. For this purpose, we classified vegetation formation types (VFT) and measured temperature and relative humidity in places settled by Ph. opilio individuals during their daily rest. According to the predominant species, we recognized six VFTs: Carlina acaulis, Ruta divaricata, Koeleria pyramidata, Juniperus communis, understory vegetation and grazed turf. Only the spiny C. acaulis and unpalatable R. divaricata facilitated H. pastinacifolia, while also acting as nurse plants. On the other hand, Ph. opilio preferred the understory, but also settled on the other VFTs, except Ruta. During the highest daily temperature of about 38°C, Ph. opilio avoided the grazed turf. Temperature preferences refer to frequencies of individuals rather than to absolute temperature values. The frequencies were independent of sex and the VFTs. emales were more frequently found in tussocks showing higher temperature profiles (Juniperus, Koeleria). During the hot daytime, Ph. opilio was most sensitive to relative humidity, and less so to temperature, whilst the height of settlement varied in adjusting these two environmental factors. The distribution of males significantly differed between the subsequent morning, midday and evening series, but not between the morning and evening ones, while in females it differed between all the three time series. In habitats, such as stony dry pastures, low grazing intensity can maintain persistent populations of H. pastinacifolia and Ph. opilio even in extremely hot weather. Such grazing is the most convenient measure for protecting both species, especially the highly endangered Hladnikia. The major threat to such habitats is afforestation by Pinus nigra, which deserves additional management. We found that in stony pastures, low grazing intensity assures the structural heterogeneity of vegetation required to maintain persistent populations, of both H. pastinacifolia and Ph. opilio.

13

Influence of grazing exclusion on soil macro-invertebrate diversity in degraded sandy grassland (Inner Mongolia, China)

72%

Liu R.-T., Zhao H.-L., Zhao X.-Y.

Polish Journal of Ecology

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2012

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tom 60

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nr 2

In arid and semi-arid areas, heavy grazing combined with climate change cause land degradation (e.g., desertification). Grazing management is essential for ecosystem recovery and desertification control in these areas, including Northern China’s Horqin Sandy Land. However, the recovery of soil faunal community during grazing exclusion is unknown. We examined plant and soil macro-invertebrate community structure together with soil properties in three treatments in a representative degraded Horqin sandy grassland: exclosure for 15 and 10 years (15EX and 10EX) and long-term continuous grazing (CG). The vegetation cover and height increased significantly and soil bulk density decreased significantly along the gradient from CG to 15EX, but there were no significant differences in soil pH, electrical conductivity, organic carbon and total nitrogen. Soil macro-invertebrate abundance, group richness and diversity increased along the gradient from CG to 15EX, with significant differences in invertebrate abundance and group richness between CG and 15EX; there was no significant differences between CG and 10EX. There were no significant differences in soil macro- invertebrate diversity and evenness between these three treatments. These results suggested that grazing exclusion for at least 15 years might be necessary for the recovery of these fauna. The vegetation height and the soil electrical conductivity, organic carbon, and total nitrogen determined the distribution and community structure of soil macro-invertebrates. Some faunal groups lived in specific habitats due to strong adaptation to different management practices. For example, the Thomisidae, Philodromidae, Salticidae, and Rhopalidae tended to live in habitats with tall vegetation. The Lygaeidae, Miridae, Teneberionidae, and Linyphiidae adapted to live in soil with low soil organic carbon and nitrogen (ungrazed grassland).

14

Dynamics of Theileria orientalis genotype population in cattle in a year-round grazing system

72%

Masatani T., Yoshihara S., Matsubara A., Gotoh T., Takahashi H., Tanaka T., Andoh M., Endo Y., Matsuo T.

Acta Parasitologica

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2016

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tom 61

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nr 2

15

Microbial plankton communities in the coastal Southeastern Black Sea: biomass, composition and trophic interactions

72%

Aytan U., Feyzioglu A. M., Valente A., Agirbas E., Fileman E. S.

Oceanologia

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2018

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tom 60

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nr 2

16

Grazing preference of Ceratophysella sp. 1 (Collembola) for Pseudoperonospora cubensis - fungal pathogen of Cucumis sativus

72%

Chlebicki A., Radwanski J. M.

Acta Mycologica

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2014

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tom 49

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nr 1

Grazing preferences of collembolans Ceratophysellasp. 1 were noted. The collembolans feed on the sporangia of Pseudoperonospora cubensisgrowing on plants Cucumis sativusin greenhouses in Esfahan province in Iran. Sporangia of Pseudoperonospora cubensiswere the preferred food of all fungal species noted in the alimental tract of the springtails. All digestive tracts of the springtails contained sporangia of P. cubensis.

17

Protozoan impact on bacterial biofilm formation

72%

Rychert K., Neu T. R.

Biological Letters

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2010

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tom 47

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nr 1

18

Ramet recruitment from different bud types along a grassland degradation gradient in Inner Mongolia, China

72%

Qian J., Busso C. A., Wang Z., Liu Z.

Polish Journal of Ecology

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2015

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tom 63

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nr 1

Since the contribution of total belowground bud bank and different bud types to community regeneration has rarely been explored, the vegetative offspring recruited from different belowground bud types was investigated in four plant communities along a grassland degradation gradient in northeastern China (Inner Mongolia). This gradient, between 1000 and 1500 m a.s.l., has been caused by overgrazing. It is a Leymus chinensis steppe which occupies about 3.0×10⁵ ha. Recruitment from tiller buds was dominant (>80%) in determining the total vegetative offspring density along the whole grassland degradation gradient. However, the proportional contribution of tiller-ramets to total ramet recruitment was significantly greater (P <0.05) during earlier than later stages of grassland degradation, while that of rhizome-ramets showed an opposite pattern. While the percentage contribution and density of root-derived ramets to total ramet density increased significantly (P <0.05) during the late stages of grassland degradation, those of bulb-ramets kept relatively constant along the whole grassland degradation gradient. The relative contribution of hemicryptophytes [i.e., Achnatherum sibiricum, Cleistogenes squarrosa, Festuca ovina, Koeoleria cristata, Poa annua, Stipa grandis] to total plant species richness decreased, while that of geophytes [i.e., Agropyron cristatum, Carex korshinskyi. Leymus chinensis, Allium anisopodium, A. bidentatum, A. tenuissimum, Astragalus galactites, Cymbaria dahurica, Iris tenuifolin, Potentilla acaulis, P. bifurca, Pulsatilla turczaninovii, Serratula chinensis, Thalictrum aquilegifolium] increased with the increases of grassland degradation. Our results showed that as grassland degradation increased, changes in the proportion of tiller-, rhizome- and root-derived ramets with respect to total ramet density determined in turn changes in the proportion of hemicryptophytes and geophytes in the study plant communities.

19

Fractal features of soil particle size distributions and their implications for indicating enclosure management in a semiarid grassland ecosystem

72%

Chen W., Chang H., Liu R.

Polish Journal of Ecology

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2020

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tom 68

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nr 2

20

Field and molecular evaluation of anthelmintic resistance of nematode populations from cattle and sheep naturally infected pastured on mixed grazing areas at Rio Grande do Sul, Brazil

72%

Ramos F., Marques C. B., Zamperete Raginato C., Braunig P., Osmari V., Fernandes F., Sangioni L. A., Vogel F. S. F.

Acta Parasitologica

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2020

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tom 65

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nr 1

Ograniczanie wyników

Forage patch use by grazing herbivores in a South African grazing ecosystem

The effect of grazing on the population of Plantago coronopus L.

Effect of long-term abandonment and spring grazing on floristic and functional composition of dry grasslands in a Central Apennine farmland

Plant functional trait response to habitat change and grazing in a semiarid grassland: unravelling species turnover and intraspecific variation effects

Constitutive and induced chemical defenses against insect grazing on leaves of forest understory shrubs