Research Methods

2. Research Methods

possible to classify them to a valorization class The performed investigations comprised the according to O świt [11] as follow: following communities differing with respect to the

Natural

Range of average

rate (index) site conditions in which they occur: Phalaridetum

valorisation class Natural value

< 1.4 arundinaceae (KOCH 1926 n.n.) Libb. 1931,

I Very small

II Average small 1.5-1.8 Alopecuretum pratensis (REGEL 1925) Steffen 1931,

III Small 1.9-2.2 with Deschampsia caespitosa Horvati

IV Moderate ć 1930, 2.3-2.6

V Medium moderate Holcetum lanati Issler 1936, Lolio-Cynosuretum R.Tx. 2.7-3.0 VI Moderate huge 3.1-3.4

1937, with Poa pratensis-Festuca rubra Fija łk. 1962 VII Huge 3.5-3.8

pro ass. They were identified on the basis of the VIII Very huge 3.9-4.2 analysis of about 450 phytosociological reléves taken

IX Outstanding 4.3-4.6

X Unique > with the assistance of the Braun-Blanquet method. 4.6 Phytosociological reléves were performed in the time

(5) fodder value score (FVS) after Filipek [12]— between the middle of May and the middle of July from

adopts a system of numbers of fodder value ranging the area of 75-100 m 2 . After assigning reléves to the

from 10 to 3 and the sward fodder value is calculated as phytosociological system the following parameters

a quotient of percentage share of a species and its FVN were assessed:

and is classified as:

(1) Total species number as well as mean number of Fodder value score

Sward

very good

8.1-10.0

species in a phytosociological reléve;

good

6.1-8.0

(2) Shannon-Wiener diversity index (H’) [9] bad 3.1-6.0 H’ = – ∑ (pi * log pi) (1)

poor < 3.0

where Site wetting was determined based on the F index pi = n / ∑n

[13] as well as on the level of ground waters. n: number of occurrences of a given species in a

These investigations were established on ten community; ∑ n: number of all species in a community.

representative areas that differed as to the level and (3) Geographic-historic spectrum, (according to

intensity of utilisation. It investigated phytocenoses Jackowiak) [10] that divides plant species according to

developed in the conditions of: lack of utilisation (A), their response to human activities into:

occasional cutting (B), occasional alternating

a: non-synanthropic spontaneophytes (Sp)—native meadow-pasture utilisation (C), pastures with uncut species which developed in a given area or came from

left-overs (D), 2 cuts and light grazing of the sward by other areas and can exist without human assistance;

cattle (E) and 2-3 cuts (F).

The Effect of Utilisation on the Floristic Composition of Meadow Communities

3. Results

of the botanic composition as a result of domination of such common plant species as: Potentilla reptans,

Utilization possibilities, its type and intensity as well Agropyron repens, Deschampsia caespitosa, Urtica as the accuracy of the performed maintenance

dioica, or Rumex acetosa.

treatments of grass communities depended on site

A small decline in the number of plant species in the wetting and affected their floristic composition.

sward was also observed in patches of Phalaridetum Strong wetting of sites (F index exceeded 8.5)

Alopecuretum pratensis, throughout the vegetation season made sward cutting

arundinaceae,

Lolio-Cynosuretum or Poa pratensis-Festuca rubra impossible; limited sporadic mowing was impossible

communities when they were utilised intensively, i.e., either among the evaluated communities such

cut or grazed twice or three times. In such conditions, conditions favoured the occurrence of Phalaridetum

species of sown cultivated grasses and legumes arundinaceae phytocenoses only. Decreasing site

wetting (F from 6.6 to 8.4) made utilisation possible exhibited the highest share and, therefore, both in the and the number of cuts as well as the performed

case of sporadic utilisation as well as when such areas maintenance treatments of red canary grass meadows

were managed intensively the proportion of depended on the duration of flooding. At prolonged

synanthropic species increased to over 80%. Their periods of flooding (F about 6.3) sward systematic

presence influenced negatively, among others, natural utilisation and maintenance were difficult.

values of plant communities in the assessed research Shortening of flooding and protracted high levels of

points (Table 1).

ground waters (F from 6.6 to 5.0) resulted in the However, unfavorable natural changes associated development of communities from the with the utilisation intensity turned out to be positive Molinio-Arrhenatheretea class and made it possible to

from the point of view of agriculture. This is perform 2 or even 3 sward cuts or to allow animal

corroborated by the calculated values of the sward grazing. With decreasing site wetting (F below 6), the

fodder value that increased when it was utilised number of cuts on meadows as well as rotations on

intensively.

pastures declined. Their number or frequency It was observed that regular cutting of the sward of depended on the levels of precipitation as it communities that had earlier been utilised only preconditioned sward regrowth after cutting.

accidentally resulted in the restoration of their fodder The employed type of meadow utilization and

value score.

cutting did not only affect the floristic composition of