scholarly journals Effects of drainage on the botanical richness of peat grassland.

1987 ◽  
Vol 35 (2) ◽  
pp. 103-111
Author(s):  
A.J. van Strien ◽  
T.C.P. Melman

Data on botanical composition from 3 studies involving drainage of peat grasslands in 1940-75 were reanalysed by means of analysis of variance using total number of plant species, number of quality-indicating species and a system in which species were weighted according to rarity and rate of decline. Alopecurus geniculatus, Glyceria fluitans and Phalaris arundinacea were used as moisture indicators, and Dactylis glomerata and Poa pratensis as drought indicators. On extensively exploited grasslands drainage alone had considerable adverse effects on species richness whereas on intensively managed grasslands the N supply had the dominant effect. Results indicated that there was little or no advantage to nature conservation in omitting drainage where grassland was intensively managed. (Abstract retrieved from CAB Abstracts by CABI’s permission)

1967 ◽  
Vol 15 (2) ◽  
pp. 127-140
Author(s):  
M. Hoogerkamp ◽  
J.J. Woldring

In periods with a precipitation excess and in many springs the grass yield of old grassland and leys on a heavy river-clay soil was highest on the deepest drained plots. In dry periods the yield decreased with increasing depth of drainage. In the wet periods yields were affected by differences in N supply; in dry periods water supply was the main limiting factor. With grazing, grass growth and utilization were unfavourably affected by high groundwater levels in wet periods. The botanical composition of the sward changed gradually under the effect of groundwater level, but true moisture or drought indicators did not occur. (Abstract retrieved from CAB Abstracts by CABI’s permission)


1981 ◽  
Vol 96 (1) ◽  
pp. 89-97 ◽  
Author(s):  
J. H. McAdam

SUMMARYExperiments to determine the effects of a range of applied lime and phosphate treatments on the establishment of species and the subsequent herbage production in the first and second seasons following sowing on four sites in the Falkland Islands are described and the results discussed.Festuca rubra, Dactylis glomerata, Phleum pratense and Poa pratensis established, successfully yielding up to 4·5 t D.M./ha per year with inputs of 55 kg N, 50 kg P and 20 kg K/ha. Applied P increased the yield of herbage and produced a small, though significant, increase in P status of the soil.The lowest level of applied lime (0·63 t/ha) increased the soil pH to 5·0 and although this did not affect the yield or botanical composition of the grass component of the sward it did affect the presence and nodulation of white clover.The problems of establishing white clover are presented in view of the severe limitations on the use of lime and fertilizer in the Islands. The implications of grazing this improved pasture are discussed in relation to increased pasture production and improved soil fertility.


1983 ◽  
Vol 63 (1) ◽  
pp. 267-276 ◽  
Author(s):  
R. L. NICHOLS ◽  
R. A. PETERS

Birdsfoot trefoil (Lotus corniculatus L. ’Viking’) was seeded directly into a predominantly orchardgrass (Dactylis glomerata L.) sward following overall or banded applications of paraquat (1,1′-dimethyl-4, 4′-bipyridinium ion, as dichloride salt) or glyphosate [N-(phosphonomethyl)glycine, as isopropylamine salt] to determine the degree of sward control necessary for stand establishment without tillage. Effects of the herbicide treatments and the seeding on botanical composition and dry matter production were determined by a vertical intercept technique and by hand separations of harvests into botanical components. Trefoil establishment was proportional to the degree of sward control during the seeding year. Little trefoil was established by direct seeding without herbicides. The banded herbicide treatments were less effective than overall herbicide applications for trefoil establishment. Trefoil yield obtained following overall application of paraquat was approximately 65% of that obtained following overall glyphosate treatment.Key words: Dactylis glomerata, glyphosate, Lotus corniculatus, herbicide, no-tillage, paraquat


1983 ◽  
Vol 61 (8) ◽  
pp. 2186-2194 ◽  
Author(s):  
Roy Turkington

Replicates of two genotypes of Trifolium repens L., collected from a Poa pratensis dominated sward and a Dactylis glomerata dominated sward, respectively, were grown in swards composed of various proportions of P. pratensis and D. glomerata. These swards represented a range of environments of neighbours; an increasing proportion of P. pratensis was considered as an increasingly alien environment for individuals of T. repens collected from the D. glomerata dominated site, and vice-versa for the individuals from the P. pratensis dominated site. The individuals of T. repens were harvested on five occasions over a period of 27 months. Both genotypes responded to increasingly alien environments by producing more inflorescences and by distributing proportionately more dry matter to inflorescence production. Some evidence is also presented which suggests that allocation to stolons and inflorescences are alternatives and the balance of the trade off is dependent on the advantages of possibly producing new, better adapted offspring from seed, against the chances of a wandering stolon encountering a less hostile environment. Results are discussed in the context of environmental alienness, a major source of which is the different relative proportions of neighbours. The various genotypes of organisms which a relatively mobile plant species encounters are a major source of this environmental, or biotic, alienness.


2019 ◽  
Vol 65 (No. 6) ◽  
pp. 307-312 ◽  
Author(s):  
Jadwiga Wyszkowska ◽  
Agata Borowik ◽  
Jan Kucharski

Resistance of common European grasses to diesel oil and petroleum pollution is not well-known. Therefore, this study aimed at determining the level of resistance of selected grasses to pollution by diesel and petroleum using the pot experiment. The achieved results were compared with those determined for grasses grown on the non-polluted soil. Soil pollution with the tested products was found to significantly decrease the yield of all grasses, with the decrease being lower upon soil pollution with petroleum than with diesel oil. The most resistant to the pollution with diesel oil and petroleum were Phleum pratense L., Lolium perenne L. and Lolium × hybridum Hausskn. The degradation of particular groups of polycyclic aromatic hydrocarbons (PAHs) depended on their chemical properties, on the type of pollutant and grass species. The greatest degradation was determined in the case of BTEX, C<sub>6</sub>–C<sub>12</sub> benzines as well as 2- and 3-ring hydrocarbons, whereas the lowest in the case of 5-and 6-ring hydrocarbons and C<sub>12</sub>–C<sub>25</sub> oils. The most useful species in the remediation of soils polluted with diesel oil and petroleum turned out to be: Lolium perenne L., Lolium × hybridum Hausskn and Phleum pratense L., whereas the least useful appeared to be: Festuca rubra, Dactylis glomerata L. and Poa pratensis L.


2009 ◽  
Vol 6 (1) ◽  
pp. 59-66 ◽  
Author(s):  
M. Mattsson ◽  
B. Herrmann ◽  
S. Jones ◽  
A. Neftel ◽  
M. A. Sutton ◽  
...  

Abstract. Species diversity in grasslands usually declines with increasing input of nitrogen from fertilizers or atmospheric deposition. Conversely, species diversity may also impact the build-up of soil and plant nitrogen pools. One important pool is NH3/NH4+ which also can be exchanged between plant leaves and the atmosphere. Limited information is available on how plant-atmosphere ammonia exchange is related to species diversity in grasslands. We have here investigated grass species abundance and different foliar nitrogen pools in 4-year-old intensively managed grassland. Apoplastic pH and NH4+ concentrations of the 8 most abundant species (Lolium perenne, Phleum pratense, Festuca pratensis, Lolium multiflorum, Poa pratensis, Dactylis glomerata, Holcus lanatus, Bromus mollis) were used to calculate stomatal NH3 compensation points. Apoplastic NH4+ concentrations differed considerably among the species, ranging from 13 to 117 μM, with highest values in Festuca pratensis. Also apoplastic pH values varied, from pH 6.0 in Phleum pratense to 6.9 in Dactylis glomerata. The observed differences in apoplastic NH4+ and pH resulted in a large span of predicted values for the stomatal NH3 compensation point which ranged between 0.20 and 6.57 nmol mol−1. Three species (Lolium perenne, Festuca pratensis and Dactylis glomerata) had sufficiently high NH3 compensation point and abundance to contribute to the bi-directional NH3 fluxes recorded over the whole field. The other 5 grass species had NH3 compensation points considerably below the atmospheric NH3 concentration and were thus not likely to contribute to NH3 emission but only to NH3 uptake from the atmosphere. Evaluated across species, leaf bulk-tissue NH4+ concentrations correlated well (r2=0.902) with stomatal NH3 compensation points calculated on the basis of the apoplastic bioassay. This suggests that leaf tissue NH4+ concentrations combined with data for the frequency distribution of the corresponding species can be used for predicting the NH3 exchange potential of a mixed grass sward.


1990 ◽  
Vol 68 (5) ◽  
pp. 1080-1085 ◽  
Author(s):  
Roberta Parish ◽  
Roy Turkington ◽  
Elena Klein

An artificial pasture was established using a forage seed mixture commonly used in the Fraser Valley of British Columbia. For five growing seasons, the plots were subjected to all combinations of two fertilizer levels, four frequencies of mowing, and the removal or not of small divots to create small gaps. All species were still present at the end of the study, but only Dactylis glomerata was found in all treatments; the abundance of ryegrasses (Lolium spp.) and clovers (Trifolium spp.) declined considerably, and there were significant [Formula: see text] between-year differences for all species. Mowing [Formula: see text] and fertilization [Formula: see text] had significant impacts on the abundance of all species, and there was a significant [Formula: see text] fertilization × mowing interaction effect on all species except Festuca sp. Divot removal had little impact. The number of species per plot and species diversity were highest, but the abundance of species was lowest, in unfertilized and frequently mown plots. The results are discussed in the context of tolerance to shading, nutrient application and growth rates, and competitive exclusion. Key words: mowing, fertilization, disturbance.


1959 ◽  
Vol 7 (3) ◽  
pp. 232-236
Author(s):  
D.M. De Vries ◽  
B.J. Hoogers

A survey of 1647 old permanent grasslands was carried out using 25-sq. cm. samples [see Herb. Abstr. 29, p. 1] and the frequency of dominance of each species in the samples (DF), the frequency of occurrence of each species (PF), and the dominance tendency (Dt=DF/PF X 100) was calculated for each field. Tussock-forming species showed a non-uniform distribution of tillers within the sward and the value of Dt for these species was higher than that for uniformly distributed species. Of the 29 species studied, Deschampsia caespitosa, Festuca arundinacea, Lolium perenne, Dactylis glomerata, Holcus lanatus and F uncus effusus showed high average values for Dt, while rhizomatous species such as Poa pratensis and Agropyron repens [Elymus repens], stoloniferous species such as Trifolium repens, Poa trivialis and Ranunculus repens, and species spreading by means of seed, such as R. acris, Bromus mollis and Rumex acetosa, had low average Dt values. From values of Dt calculated for fields used for hay, hay-pasture (aftermath grazed), alternate pastures (mown for hay in some years only) and pure pastures, it was shown that D. caespitosa, L. perenne, D. glomerata and J. effusus were more regularly distributed in hay-fields than in pastures. In alternate pastures, J. effusus had a low Dt value, F. arundinacea a high Dt. Species having a preference for hayfields showed higher Dt values than elsewhere, owing to their growth not being restricted by grazing. Typical pasture species which spread by means of runners, such as P. pratensis, Agrostis stolonifera and T. repens, were more homogeneously distributed in hayfields; their increased Dt values in pastures was due to their concentration in the spaces between tussocks of other species.-R.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)


2011 ◽  
Vol 48 (No. 11) ◽  
pp. 499-504
Author(s):  
J. Šantrůček ◽  
M. Svobodová ◽  
V. Brant

A&nbsp;field trial with Bromus catharticus Vahl. cv. Tacit, Arrhenatherum elatius (L.) P. Beauv. ex J.S. et K.B. Presl cv. Median, Festuca pratensis Huds. cv. Otava and Dactylis aschersoniana Graebn. cv. Tosca sown in rows 125 mm, was established in the year 1996 in Prague (chernozem, altitude 281 m a.s.l., average precipitation 472 mm per year, average year temperature 9.3&deg;C). The stands were cut one or three times per year. The mass was removed or once or twice mulched. The share of the botanical species (by weight method), number of present species and agrobotanical groups (grasses, legumes, other dicotyledonous) coverage were measured from the third to the sixth year of vegetation. The results were evaluated by the analysis of variance (Tukey&nbsp;&alpha;&nbsp;= 0.05) and by time series analysis (forecasting) by the Statgraphics Plus programme, version 4.0. The species number increased rapidly with the three times cut variant during the four years, from 4 to 25 species, under the other management it was in average from 7 to 14 species, in the sixth year. The highest share of the sown species with the lowest reduction during the years was at Arrhenatherum elatius (41&ndash;72% in the sixth year). Bromus catharticus was extinct in the fifth year. The species chosen had a&nbsp;higher importance for conserving of the original botanical composition than the way of harvest. There was the significantly lower ground cover with the variant&nbsp; one cut per year (on average less than 70%). Mulch covered 15&ndash;64% of the surface in dependence on the dry mass yield and mulching frequency. The plants coverage was highest on the two or three times harvested variants (75&ndash;80%D).


Author(s):  
B.E. Ruz-Jerez ◽  
P.Roger Ball ◽  
R.E. White ◽  
P.E.H. Gregg

This paper compares a herbal ley (of particular interest to farmers involved in the 'organic' branch of agriculture) with a conventional pasture (ryegrass-white clover) and a more intensive system (pure ryegrass receiving 400 kg fertiliser N/ha/yr) in a study lasting 2 years. The herbal ley seeds mixture was prepared following the pioneering ideas of Robert Elliot in his "Clifton ~~ ~~~~~Park"mixture,-whichbasically-included~a-group of 'non-aggressive' grasses, forage legumes and herbs. Pasture production (average of 2 years) from Herbal ley was 15 t DM/ha/yr, representing approximately 90% of the yield from the intensively managed pure ryegrass pasture receiving 400 kg N/ ha&r and some 2530% more than from ryegrassclover. A major feature of the herbal ley was substantialproductionduringlate.springandsummer, when chicory (the most dominant herb), and red clover and white clover made a major contribution to herbage yield. In winter the total yield was similar tothatI?omthegrass-cloverpasture.L.egumecontent was 23 and 3 1% (averaged over the year) for Grassclover and Herbal ley pastures respectively. In spite of this difference, symbiotic N fixation was similar. So fixation efficiency on a legume yield basis was 50.3 and 3 1.6 kg N fixed/t legume DM harvested, respectively. These results could reflect a different pattern of utilisation of soil N, as a consequence of the different botanical composition of the swards. In summary, the performance of the herbal ley offers the promise of an alternative, 'specialist' pasture and would be highly beneficial if quality feed is required in summer. Keywords herbal ley, biological fertility, nitrogen, symbiotic nitrogen fixation, pasture mixtures


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