A survey of mountain pasture topsoil was undertaken first to set up field experiment in karst region on effects of applied P on minerals concentration in herbage. Content of SOM, C, N, CEC of soil ...and its base saturation are presented in the article. Great variability in depth, pH value and K level was found in soil. Low base saturation and high deficit of P was more common for all soil samples. Six different plant species presenting a great portion of herbage available for grazing and browsing at different occasions during grazing season were sampled and analysed for macro- and some microminerals. Concentration of P was very low in perennial grasses (1.1 g P kg−1 of DM). In leaves of common hazel (Corylus avellana L.) and common beech (Fagus silvatica L.) the concentration of P was identical as in white clover (Trifolium repens L.) and the level was high enough to cover animal needs when intake of herbage was sufficient. Leaves of woody plants were high in Mn concentration, but still below the levels that reduced growth rate in lambs. Application of P fertilizer had only small effect on increase of P in herbage, but large one on decrease on concentration of Ca in herbage. There was not clear effect of added P on concentration of Zn, Mn, Fe and Cu. Higher yield of DM induced with added fertilizer had not have any dilution effect on concentration of those minor elements in herbage.
Predstavljeni so rezultati 7-letne raziskave o vplivu dodanega P na njegovo dostopnost v tleh, na vsebnost P v zelinju kraškega pašnika in na povečanje mase razpoložljivega zelinja pri stopnjujočem ...se odmerku uporabljenega gnojila (0, 90, 270 in 540 kg P2O5 ha-1 skupno v 3 letih). Koncentracija dostopnega P v tleh je bila v obravnavanju nizek odmerek (30 kg P2O5 ha-1 letno) večja za 2,4 mg P2O5 100 g-1 tal od kontrolnega obravnavanja. S trikrat večjim odmerkom gnojila je bila vsebnost P v tleh povečana za 4,4-krat. Vzorčenje zemlje do dveh globin (0 - 3 cm in 3 - 6 cm) je pokazalo, da je večji del razpoložljivega P za rast rastlin v vrhnji, zelo plitvi plasti zemlje. V petih rastnih sezonah po zadnjem gnojenju s P se je zmanjšala koncentracija dostopnega P v tleh od 0,4 mg do 3,6 mg P2O5 100 g-1 tal, odvisno od skupno uporabljenega gnojila. Zaradi izredne siromašnosti zemlje kraškega pašnika s P, je tudi njegova vsebnost v zelinju ruše zelo nizka. Zadošča le za polovično pokritje potreb pašnih živali po tej rudnini, zato je povečanje vsebnosti P v zelinju pri gnojenju s fosfati pomembnejše od povečanja pridelovalne zmogljivosti zemljišča. Z letnim odmerkom 90 kg P2O5 ha-1 se je v treh rastnih sezonah v povprečnem vzorcu zelinja koncentracija P povečala na 2,1 g P kg-1 SS. Uporabljen P je imel na maso zelinja razpoložljivega za pašo in na delež izkoriščenosti ruše majhen vpliv, najverjetneje zaradi kisle reakcije tal in počasnega izboljšanja floristične sestave ruše.
In the work described in this paper, the effects of sulphur (S) fertilizers in combinations with nitrogen (NP) and phosphorus (P) fertilizers on herbage production were investigated. Results from the ...first three years of experiment carried are reported. Field experiment was carried out at mountain sheep pasture Vremščica. Sulphur was added at a rate of 60 kg ha-1. Same was for nitrogen. Phosphorus was applied at 90 kg ha–1 each year. As a result of more balanced supply of nutrients to plants, and the sheep grazing, the similar herbage mass was obtained few days earlier during each consecutive year. Most efficient on average was the combined application of NPS which gave 24 % higher yield of herbage than control treatment. Statistically significant differences were found (P=0.05) further for NP, NS and NPK treatments too. Clover content showed a trend for a slight decline on treatments where N was applied. This small decrease in clover content was probably a result of the shading of clovers by grasses. Amount of herbage utilised during two rotations was 3.5 t ha –1 DM for NPS treatment, and this was for 67 % higher from what was achieved on control treatment.
Proučevan je bil vpliv gnojenja z žveplom (S) v kombinaciji z dušikom (N) in fosforjem (P) na pridelek zelinja kraškega pašnika. Prikazani so rezultati dela prvih treh let. Poljski poskus je bil izveden na planini Vremščica, na pašniku za ovce. Z žveplom je bilo gnojeno 60 kg ha-1. Enako je bilo z dušikom. Fosfor je bil dan vsako leto v odmerku 90 kg ha –1. Učinek uporabljenih gnojil in pašne rabe ruše se je pokazal v ranejšem pričetku rasti ruše vsako naslednje leto. V povprečju je bila najbolj učinkovita uporaba NPS gnojil skupaj, ki je dala za 24 % večjo maso razpoložljivega zelinja v primerjavi z negnojenim postopkom. Statistično značilne razlike (P=0,05) so bile ugotovljene tudi za postopke gnojenja NP, NS in NPK. Delež bele detelje se je nekoliko zmanjšal na postopkih, kjer je bil uporabljen dušik. To zmanjšanje je bilo verjetno posledica senčenja detelje zaradi višje rastočih trav. Skupna masa zelinja, ki so ga ovce izkoristile v dveh obhodih je znašala na postopku NPS 3,5 t ha–1 SS, kar je za 67 % več kot je bilo ugotovljeno za kontrolni postopek.
The Slovenian Karst Plateau is presented in the article and reviewed are the possibilities for the development of sustainable grassland utilisation with livestock grazing. This can have positive ...impact on the biodiversity of the region and on well kept appearance of the landscape. Limestone and dolomite rocks form karstic character of land, which is expressed through geomorphological, hydrographical as well as floristic and vegetational, soil, agricultural, and settlement pattern. The key indicator for a land stability and productivity is succession. It is the process of change and development in entire communities; soil, micro-organisms, animals and plant life. To understand the nature of the forces that influence individual plants within the Karst pasture sward, we need to consider what happens in the sward from the plant's point of view. To maintain karst grassland and prevent it from bush encroachment, the grazing of livestock is of vital importance. Grazing livestock greatly affects the composition of pasture plant communities. With proper grazing management animals always cause pasture to be a more complex mixture of plants than it otherwise would be. This is because animals graze selectively and in patches, and the effects vary in time and space. They do collect the nutrients from wider area and return them more concentrated to the soil. This has great influence on site fertility and vitality of the ecosystem. All this has an effect on sward development, which contains a wide variety of plants adapted enough to survive their different local conditions. It is quite logical that throughout the process of evolution, the pasture plants and animals have adapted to each other and that grazing is not harmful to those plants.
V prispevku je predstavljen slovenski kraški plato s stališča ohranjanja travnatega sveta za potrebe pašne reje domačih živali, večanje biodiverzitete in vzdrževanja negovanega izgleda pokrajine. Apnenci in dolomiti tvorijo tipičen kraški karakter, ki ga označujejo raba tal, gemorfološke, hidrografske, vegetacijske in talne značilnosti. Ključni indikator stabilnosti in proizvodne sposobnosti kraškega travnatega sveta je sukcesija. To je proces sprememb in razvoja v sistemu tal, mikroorganizmov, rastlin in živali. Da bi razumeli naravo in vpliv posameznih rastlin v travni ruši moramo preko meritev in opazovanj prepoznati najbolj tekmovalne rastlinske vrste. Za vzdrževanje kraškega travinja in preprečevanje širjenja grmovne zarasti je lahko paša eno izmed pomembnih orodij. S pravilno vodenim sistemom nadzorovane paše lahko povečamo raznolikost in obilnost rastlinskih vrst, ki naseljujejo določeno območje. Pomen živali na paši v razmerah kraškega travinja je tudi zbiranje in vračanje rudnin, ki so pomembne za rodovitnost zemlje ter življensko moč ekosistema. V tem je pomembnost njihovega značilnega vpliva na smer razvoja rastlinske združbe obravnavanega območja.
V raziskavi smo proučevali učinek ovcam in kozam v obrok dodanega izvlečka taninov lesa pravega kostanja (Castanea sativa Mill.), ki vsebuje 74 % pretežno hidrolizirajočih taninov. V poskus smo ...vključili 21 jagnjic in 10 koz, ki so se pasle na kraškem pašniku. Trinajstim jagnjicam in petim kozam smo vsake tri dni peroralno dajali pripravek kostanjevih taninov v odmerku 0,5 g kg–1 telesne mase. Osem jagnjic in pet koz smo spremljali kot kontrolni skupini. Živali so se pasle skupaj v ogradah na istem pašniku. Poskus je trajal 68 dni. Jagnjice poskusne skupine so na paši priraščale v povprečju 37 g dan–1, jagnjice kontrolne skupine pa 18 g dan–1. Razlike v dnevnih prirastih jagnjic niso bile statistično značilne. V prvem obdobju (35 dni) je bilo v iztrebkih jagnjic poskusne skupine manj SS (189–217 g kg–1 vs. 195–229 g kg–1), več SB (177–157 g kg–1 SS vs. 170–142 g kg–1 SS) in več taninov (0,77–0,61 % v SS vs. 0,73–0,52 % v SS) kot v iztrebkih jagnjic kontrolne skupine. Povezava med vsebnostjo taninov in surovih beljakovin v iztrebkih jagnjic je bila statistično značilna (r = 0,92, P < 0,05). Rezultati kažejo, da dodani kostanjevi tanini vplivajo na sestavo blata, kar je verjetno posledica mesta prebave zaužitih hranil. Obe skupini koz sta v poskusu hujšali (–79 g dan–1). V iztrebkih koz je bilo več suhe snovi (192–297 g kg–1) in manj surovih beljakovin (108–144 g kg-1 SS) ter taninov (0,24–0,48 % v SS) kot v iztrebkih jagnjic.