The suitability of agricultural land for irrigation and the water deficit in the soil in the cultivation of important agricultural crops in the Međimurje County area

Cilj rada je ukazati na nedovoljno iskorištene agroekološke potencijale u razvoju poljoprivrede Međimurske županije u uvjetima aktualnih klimatskih promjena. Resursi poljoprivrednog zemljišta utvrđeni su na temelju postojeće karte poljoprivrednog zemljišta RH mjerila 1:50.000. Pogodnost poljoprivrednog zemljišta za natapanje prikazana je na temelju Namjenske pedološke karte Međimurske županije mjerila 1:50.000. Osnovne značajke klime te manjak vode u tlu prikazani su za kukuruz, kupus, krumpir i jabuku, a utvrđeni su zasebno za prvo razdoblje 1981.-1999., te za drugo razdoblje 2000.-2021. Pri tome je referentna evapotranspiracija utvrđena prema Penman-Monteith metodi, a bilanca oborinske vode u tlu prema Palmer metodi korištenjem programa Hidrokalk. Manjak vode u tlu utvrđen je iz razlike potencijalne evapotranspiracije kultura i aktualne evapotranspiracije. Od ukupnih 48.882,0 ha poljoprivrednog zemljišta Međimurske županije, koristi se oko 82 % a ne koristi oko 18 %. Korištenog zemljišta u privatnom je vlasništvu 89,2 %, u državnom 4,8 %, a u mješovitom 6 %. Nekorištenog zemljišta u privatnom je vlasništvu 86,4 %, u državnom 11,9 %, a u mješovitom 1,7 %. Na korištenom poljoprivrednom zemljištu najviše je zastupljeno tala P-2 klase pogodnosti za natapanje (72,5 %), potom N-1 klase (18,4 %), P-3 klase (9,0 %) i P-1 klase (0,1 %). Kod nekorištenog zemljišta dominiraju tla P-2 klase (50,8 %), potom N-1 klase (35,3 %) te P-3 klase (13,9 %). Višegodišnja prosječna godišnja količina oborina u drugom klimatskom razdoblju bila je za 56,6 mm manja, a temperatura zraka za 0,9 ºC viša u odnosu na prvo klimatsko razdoblje. U vegetacijskom razdoblju (IV-IX mjesec) drugog klimatskog razdoblja prosječna količina oborina bila je također manja i to za 24,5 mm a temperatura zraka viša za 0,9 ºC u odnosu na prvo klimatsko razdoblje. U sušnim godinama, odnosno kod 75 % vjerojatnosti oborina, višegodišnja prosječna godišnja količina oborina u drugom klimatskom razdoblju bila je za 108,7 mm manja a temperatura zraka za 0,9 ºC viša u odnosu na prvo klimatsko razdoblje. U vegetacijskom razdoblju prosječna količina oborina u drugom klimatskom razdoblju bila je manja za 74 mm, dok je temperatura zraka bila viša za 0,6 ºC u odnosu na prvo klimatsko razdoblje. U drugom klimatskom razdoblju tijekom vegetacije utvrđeni je veći manjak vode u tlu u odnosu na prvo razdoblje. U prosječnim godinama najveća razlika u manjku vode između dva razdoblja, utvrđena je kod jabuke (48,7 mm) a najmanja kod kupusa (38,5 mm). Kod sušnih godina najveća je razlika manjka vode između dva razdoblja utvrđena također kod jabuke (129 mm), dok je kod ostalih kultura utvrđena podjednaka razlika (oko 116 mm). Kako bi se nadoknadio manjak vode u tlu nužno je na području Međimurske županije planirati primjenu natapanja.The aim of the paper is to point out the insufficiently used agroecological potentials in the development of agriculture in the Međimurje County under the current climate change conditions. The resources of agricultural land were determined on the basis of the existing map of agricultural land of the Republic of Croatia in scale 1:50,000. The suitability of agricultural land for irrigation is shown on the basis of the „Dedicated Pedological Map of Međimurje County in scale 1:50,000“. The basic climate properties and the water deficit in the soil were shown for corn, cabbage, potatoes and apples, and were determined for the first period 1981-1999 and for the second period 2000-2021, separately. At the same time, the reference evapotranspiration was determined according to the Penman-Monteith method and the balance of precipitation water in the soil according to the Palmer method using the Hidrokalk program. The soil water deficit was determined from the difference between potential evapotranspiration of crops and actual evapotranspiration. Of the total 48,882.0 ha of agricultural land in Međimurje County, about 82% was used and about 18% was unused. 89.2% of the used land is privately owned, 4.8% is state-owned, and 6% is mixed owned. Unused agricultural land is privately 86,4%, state 11.9%, and mixed owned 1,7%. On the used agricultural land, the most represented soil is P-2 class suitable for irrigation (72.5%), followed by N-1 class (18.4%), P-3 class (9.0%) and P-1 class (0.1%). Unused land is dominated by P-2 class soils (50.8%), followed by N-1 class (35.3%) and P-3 class (13.9%). The long - term average annual precipitation in the second climate period was 56.6 mm lower, and the air temperature was 0.9 ºC higher compared to the first climate period. In the vegetation period (IV-IX months) of the second climatic period, the average amount of precipitation was also lower by 24.5 mm and the air temperature was higher by 0.9 ºC compared to the first climatic period. In dry years, with a 75% probability of precipitation, the long-term average annual precipitation in the second climate period was 108.7 mm lower and the air temperature was 0.9 ºC higher compared to the first climate period. In the vegetation period, the average amount of precipitation in the second climatic period was lower by 74 mm, while the air temperature was higher by 0.6 ºC compared to the first climatic period. In the second climatic period during the crop vegetation, a greater soil water deficit was found compared to the first period. In average years, the highest difference in soil water deficit between the two periods was found in apple (48.7 mm) and the lowest in cabbage (38.5 mm). In dry years, the highest difference in water deficit between the two periods was also found in apple (129 mm), while the same difference was found in other crops (about 116 mm). In order to compensate for the soil water deficit, it is necessary to plan the application of irrigation process in the Međimurje County area