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  • Different agrotechnical mesures on the ecology and conservation in a wet meadow
    3-15
    Views:
    69

    In grassland management systems, the various agrotechnical elements have to be used in many cases on "primitive grasslands", where the coordination of agricultural and nature conservation tasks is necessary. Here, animal husbandry is the main aspect, which includes the long-term preservation of the quality of the pasture, as well as the most economical use of the pasture and keeping the animals as cheap as possible. The tests were carried out on a grassy area on the border of the settlement of Aba. We examined the vegetation of 8 plots of the same size in the area and the quantitative and qualitative composition of the biomass produced there. In this thesis, we provide data on the vegetation composition and evaluation of the following treatments. The plots and treatments were as follows: I. plot-ventilated; II. parcel-relaxed; III. plot loosened and ventilated; ARC. parcel control; V. plot-ventilated and 15 t/ha manure; VI. plot loosened and 15 t/ha manure; VII. plot loosened, ventilated and 15 t/ha manure; VIII. plot loosened, ventilated and 30 t/ha manure. In each plot, 5 ceenological recordings were made using 4 x 4 m quadrats. The estimated coverage of each species was given in %, taking into account the proportion of grasslands and other species. Among Borhidi's plant ecological indicators, the species were evaluated based on the NB (relative values of nitrogen demand) and WB (relative soil water and soil moisture indicator numbers). The social behavior types (SZMT) were also defined based on Borhidi's work, and the nature conservation value categories (TVK) were defined according to Simon. The lifestyle analysis was performed based on Pignatti's lifestyle types.

    Based on the data, the composition of the vegetation of each plot changed significantly compared to the data of the control plot IV. A direct proportionality can be discovered between the increase in the cover value of the dominant lawn grasses, primarily Festuca arundinacea, Dactylis glomerata, Alopecurus pratensis, and Fabaeceae species (e.g. Lathyrus tuberosus, Lotus corniculatus) and the amount of applied nutrients. Based on the coenological survey of the eight examined areas, the control area (IV.) showed the most natural state, which was confirmed by the species composition and number of species. The IV. plots are close to I., II. and III. for plot recordings, which proves that aeration and loosening do not worsen the condition of the lawn, but rather promote the preservation of its natural state. The VII-VIII. plots have the smallest number of species, but based on the life form spectrum, naturalness indicators, nature conservation value categories and social behavior types, they are not very disturbed habitats.

    No significant difference can be detected between the effect of lawn loosening and lawn aeration, but III. plot, where both treatments were carried out, was closer to the control area. Regarding the effect of the lawn management methods, it was possible to produce a starting data set in the long term (with the same environmental conditions). Overall, the study gave valuable results regarding the age of change occurring during the application of different lawn management methods, and was also effective from an economic point of view.

  • The effects of fertilization on a 6 years old established grassland
    19-30
    Views:
    67

    The effect of different N, P and K supply levels and their combinations were examined in the 33rd year of a long-term fertilization experiment on the yield and mineral element content of a 6 years old established all-grass sward in 2006, with seed mixture of eight grass species. The trial was established on a calcareous chernozem soil. The soil of the growing site contained around 3% humus, 5% CaCO3, 20-22% clay in the ploughed layer and was originally moderately well supplied with available K, Mg, Mn and Cu and poorly supplied with P and Zn. The trial included 4N×4P×4K=64 treatments in 2 replications, giving a total of 128 plots. The fertilizers applied were Ca-ammonium nitrate, super phosphate and potassium chloride. The groundwater table was at a depth of 13-15 m and the area was prone to drought. The 1st cut was made on 08th June, the 2nd one on 11th September. During the vegetation period of 8.5 months in 2006, the site had a total of 397 mm precipitation. The lay-out, method and main results of the trial were published earlier (Kádár, 2004, 2008; Kádár és Győri, 2004, 2005). Main conclusions of this study are as follows:

    1. The 1st cut hay yield gave the ¾ of the total yield. Highest yields were reached with the 200 kg/ha/year N-fertilization on soil well supplied with P (Ammonium-lactate soluble P2O5: 214 mg/kg). The yield of NP control plots increased from 1.5 t/ha to about 7.5 t/ha as a function of the N×P positive interaction. The rising P supply alone was not able to enhance the yield, however the N fertilization gave 3.5 t/ha hay surplus even in the P-control treatments. N and P fertilization together resulted in 6.0-6.5 t/ha yield surpluses. The effect of K fertilization also reached 1 t/ha on the NP levels where the ammonium-lactate soluble K2O content fell below 150 mg/kg.
    2. The 2nd cut hay gave 0.5 t/ha on the NP-control plots unfertilized for 33 years, and 2.5 t/ha on the 300 kg/ha/year N treatment with well P-supply. The two cuts together resulted in yield levels between 2-10 t/ha according to the extreme NPK supply. In this year, with relatively good amount of precipitation, the hay yield surpluses for 1 kg N were 47-33-23 kg for the 100-200-300 kg/ha treatments.
    3. The C/N ratio of the 1st cut was narrowed (from 52 to 24) with N-supply and the concentration of N as well as most of the cations increased with the rising N fertilization. In the low yield of the 2nd cut the elements, metals were accumulated. The P, S and Sr were enriched in hay as a result of rising P supply, as superphosphate contains these elements. Antagonistic effect of P predominated in the uptake of other elements, metals (Na, Zn, Cu, Mo, Cr, Co). K content of the hay was lifting while other elements were dropping with the increasing K fertilization partly as a result of dilution effect (N, P, S) and mainly because of cation antagonism (Ca, Mg, Na, Sr). K-B antagonism also appeared.
    4. The N×K interactions resulted in 2-fold Sr and 18-22 fold Na content changes while N×P caused 18-22 fold changes in Mo contents, especially at the 2nd cut. As it can be seen, fertilization can have drastical effects on soil and crops. The induced element deficiencies or oversupplies can lead to diseases, disturbances in the metabolism of animals, so the soil and fodder analyses are necessary.
    5. Considering the leaf diagnostical data, the satisfactory level will be at 200 kg/ha/year N supply and 150 mg/kg ammonium-lactate soluble P2O5 and K2O level or above. The S, Ca, Mg, Fe, Mn supply were satisfactory even at the control plots, while the Zn, Cu and B levels showed deficiency. The P/Zn and K/B ratios became adversely wider in some treatments, as well as the narrowing of the Cu/Mo ratio denotes Cu deficiency and Mo oversupply.
    6. The amount of elements uptaken by hay as a sum of the two cuts and as a function of the supply/yield varied between the following values in kg/ha: 17-163 N; 36-122 K; 9-48 Ca; 6-17 P; 4-15 S; 3-14 Mg; 0,3-8,0 Na; 0,2-1,4 Fe; 0,2-0,9 Al and Mn. The other elements showed the following uptake: Zn 33-194, Sr 28-141, Ba 5-46, Cu 5-39, B 5-26, Mo 3-6 g/ha.
    7. The botanical composition was drastically modified by the aging of the grass and the nutrient supply. Only three species remained out of the eight sown species and one immigrated. Coverage of the tall fescue was between 21-70% according to the N×P supply and 44% as average; coverage of cocksfoot varied between 4-24% depending on the treatment and 18% as an average; coverage of crested wheatgrass was between 0-28% and 9% as an average; the immigrant smooth brome covered 0-24% and 9% as an average; Weed cover was 3-4% as an average at the 1st cut. Weeds thrived mainly on those areas where the grass thinned away (extreme NP-deficiency or oversupply). The total plant coverage on NP-deficient soil was about 50%, while on treatments well supplied with NP it amounted 95-97%.