Suitability of Agricultural Land for Irrigation on the Territory of Istria County

The County of Istria, with an area of 2.813 km2, covers about 90 % of the Istrian peninsula. It contains 145.350 ha of agricultural land, which is 51,7 % of the county\u27s area. Most of it, or 56,4 %, is unused or neglected agricultural land, and the remaining part, or 43,6 %, is used for various purposes. Of the total area of agricultural land in certain geomorphological units, 87 % area of White Istria, 60 % of Gray Istria, and 45 % of Red Istria is unused. The aim of this paper is to show the suitability of soil for irrigation on agricultural land of Istria County. Soil characteristics are presented based on a Soil Suitability Map of the Republic of Croatia at a scale of 1:300.000. The suitability of pedosystematic units for irrigation was assessed according to the FAO Land Evaluation Method. A total of 19 pedosystematic units were found in the county, which is shown on the map in 22 soil mapping units. The total area of soils suitable for irrigation in the Istrian County is 78.584,8 ha (68,4 % of the total agricultural area), of which 2.900,7 ha (2,5 %) belong to the S-1 good suitability class, 53.916,1 ha (46.9%) belong to the S-2 moderate suitability class, while 21.768,0 ha (19,0 %) belong to the S-3 limited suitability class. There are 36.362,0 ha of unsuitable soils for cultivation (31.6 % of the total agricultural area), of which 4.906,5 ha (4.3 %) belong to the class U-1 temporarily unsuitable soils, while 31.455.5 ha (27.3 %) belong to the class U-2 permanently unsuitable soils. Considering the area of S-1 and S-2 suitability classes for irrigation, and the fact that 46 % of these soils are located on unused agricultural land, it can be stated that in Istria there are very valuable land resources suitable for planning of intensive and sustainable agricultural development in conditions of irrigation

Temporal Changes in Soil Water Content and Penetration Resistance under Three Tillage Systems

This study aims to evaluate the impact of different tillage systems on water conservation and penetration resistance in Stagnosols on slopes. Three tillage systems were evaluated during a long-term experiment in Central Croatia in a period from 2011 to 2014, in order to identify sustainable land management practices: control treatment (CT), ploughing and other seedbed layer preparation up and down the slope; ploughing across the slope (PA) – to 30 cm, other operations depending on the crop, also across the slope; and ploughing across the slope (30 cm) with subsoiling (SUB) to 50 cm. Penetration resistance and soil water content were measured each investigated season during five terms to a depth of 60 cm. Tillage systems significantly influence soil water content and penetration resistance, but the results showed great temporal and vertical variation in each investigated season. The results also showed that in low quality Pseudogley deep loosening is required because of the inability of these soils to recover naturally. The hardness of these soils decreases after tillage, or when the moisture content increases, so the period with potentially limiting soil impedance is shorter in systems with subsoiling than in conventionally tilled soils. Fallow has been effective in reducing soil strength in non-traffic areas and increasing soil moisture content. When comparing cropping variants it was established that only a system including subsoiling ensures higher moisture content. Results indicate that since soil water content and penetration resistance were adversely affected, subsoiling should be applied continuously in Pseudogley sites in the hills. Generally, soil resistance increased with time from the date of primary tillage. Although penetration resistance values increase after tillage, the differences were attributed to temporal variation of soil water content. In this study soil moisture condition is presented as a more important factor for soil resistance than the time between primary tillage and measurements

Ponašanje polikloriranih bifenila (PCB) u zagađenom tlu na podrčju Zadra

This study analysed PCB-contaminated natural soil excavated from an area adjacent to an electrical transformer station in Zadar, Croatia. For one year, PCB concentrations were measured in the soil and leachate water under natural climatic conditions. After 12 months, a negligible quantity of Aroclor 1248 (0.024 % in average) and a total of seven key PCB congeners (IUPAC No: PCB-28, PCB-52, PCB-101, PCB-118, PCB-138, PCB-153, and PCB-180) were leached through the soils into water collected under lysimeters (0.032 % in average). Although the amounts of leached PCBs were relatively small, their range 2 µg L-1 to 15 µg L-1 substantially exceeds the maximal allowed concentration of total PCBs in fishponds which is 1 ng L-1. Soil samples were taken on two occasions from three depths from each lysimeter. The distribution of total PCBs as Aroclor 1248 equivalents and seven individual PCB congeners was determined within soil layers before and after planting seeds. In all soil plots the content of total seven PCBs and some individual PCB congeners in the surface soil layers significantly decreased. The total content of the seven PCB congeners in the surface soil layer of all soil plots decreased between 19.0 % (soil plot 2) and 47.6 % (soil plot 1) and in the middle soil layer between 8.1 % (soil plot 4) and 37.4 % (soil plot 1). PCB-28 and PCB-52 showed the highest percent of removal in all soil plots after 12 months of the experiment. The most important mechanism of removal of “lighter” congeners may be evaporation from the soil surface. Generally, our results showed that the PCBs accumulated in the deepest level of the soil, probably due to vertical transport and decreased evaporation. Some of the PCB content was lost to their degradation in the rhizosphere of the plants growing on the analysed soil plots.U ovom radu korišteno je prirodno tlo zagađeno s PCB-ima. Tlo je iskopano oko uništenog kondenzatora trafostanice Zadar (ETS 110/35 kV). Eksperiment je proveden pod prirodnim klimatskim uvjetima tijekom jedne godine, kako bi se mjerila razina PCB-a u tlu i procjednim vodama. Pokusna površina sastoji se od 4 gredice. Na svakoj gredici postavljena su tri lizimetra. Nakon 12 mjeseci (12 perioda u sakupljanju procjednih voda) relativno male količine Aroclora 1248 (prosječno 0,024 %) i sume 7 ključnih kongenera PCB-a (IUPAC No: PCB-28, PCB-52, PCB-101, PCB-118, PCB-138, PCB-153 i PCB-180) nađene su u procjednoj vodi (prosječno 0,032 %). Međutim, ukoliko se uzme u obzir da su maksimalno dopuštene razine PCB-a u ribogojilištima 1 ng L-1, razine izmjerene u procjednim vodama u rasponu od 2 µg L-1 do 15 µg L-1 su više nego značajne. Tijekom dva uzorkovanja analizirano je tlo sa svakog lizimetra na tri dubine. Prije i poslije sijanja biljaka istraživana je raspodjela ukupnih PCB-a tj. sadržaj Aroclora 1248 i pojedinačnih sedam ključnih PCB-a unutar analiziranih slojeva. U površinskom sloju tla svih gredica uočeno je značajno smanjenje sume sedam ključnih PCB-a i pojedinih kongenera PCB-a. Nakon 12 mjeseci, najveći postotak smanjenja zagađivala određen je u tlu gredice br. 1. Rezultati ukazuju da se sadržaj sume sedam ključnih PCB-a u površinskom sloju tla svih gredica smanjio i taj gubitak je u rasponu od 19,0 % (gredica br.2) do 47,6 % (gredica br.1). U srednjem sloju tla gubitak sume sedam ključnih PCB-a je u rasponu od 8,1 % (gredica br.4) do 37,4 % (gredica br.1). Tijekom pokusa u tlu svih gredica uočen je najveći gubitak PCB-28 i PCB-52. Jedan od glavnih mehanizama odgovornih za gubitak niže kloriranih kongenera PCB-a iz površinskog sloja tla je hlapljenje. Općenito, rezultati ukazuju na povišene razine PCB-a u dubljim slojevima tla u odnosu na površinski sloj, vjerojatno zbog vertikalnog transporta PCB-a i manjeg hlapljenja. Osim toga, određeni gubitak PCB-a sigurno je i posljedica njihove razgradnje u rizosferi nađenog biljnog pokrova istraživane zemljišne pokusne površine

Hydropedological Map of the Republic of Croatia

The project Hydropedological Map of the Republic of Croatia was implemented using the ESRI program package. It includes the Basic Hydropedological Map with the attribute database of hydropedological mapping units, pedological and hydropedological profi les and hydrological and hydropedological parameters. The cartographic attribute database of the Basic Hydropedological Map comprises hydropedological units – types of moistening by surface water and/or ground water. The soil water retention capacity of particular hydropedological units varies from 248 to 635 mm/m, water infiltration into soil ranges from 0.01 to 7.32 m/day, hydraulic conductivity for 1 m soil depth is from 0.01 to 6.84 m/day, and from 0.01 to 15.6 m/day for 2 m depth. Annual effective precipitation of 25% occurrence probability varies from 551 to 2294 mm, and that of 75% occurrence probability is between 272 and 1180 mm. Maximum one-day runoff coefficient in the conditions of different soil texture and different vegetative cover ranges from 0.24 to 0.94 (25% probability) and from 0.02 to 0.89 (75% probability). Water deficit in soils of different texture (25% occurrence probability) varies annually from 0.0 to 513 mm/m, and deficit of 75% occurrence probability varies from 30 to 857 mm/m. Water surplus in soils of different texture (25% occurrence probability) varies annually from 57 do 1686 mm/m, and surplus of 75% occurrence probability ranges from 0.0 to 606 mm/m. The Applied Hydropedological Map of the Republic of Croatia comprises priority amelioration units for agricultural land reclamation and management

Ekogeografske karakteristike lokacija lokalnih populacija crvene djeteline na području sjeverozapadne Hrvatske

Red clover, although primarily used for dairy cow feeding, can also repair soil structure, fix atmospheric nitrogen and prevent soil erosion. Until recently, the traditional cultivation of red clover in Croatia prevailed in suitable habitats. Abandoning of agricultural production is the reason of meadows succession process which can cause genetic erosion and threatens the survival of local population of red clover. Determining of sites according to their ecogeographical characteristics could help to improve the direction of action aimed at conservation of biological diversity of species in its natural habitats as well as the preservation of genetic resources and their use in breeding purposes. The aim of this research was to classify the sites of natural habitats of red clover local populations (under extensive agricultural production) in north-western part of Croatia on the basis of their ecogeographical characteristics. Data of geographical, pedological and climatological characteristics and floristic composition were collected at 18 sites and subjected to multivariate analysis. The main differences among sites were detected in geographical, pedological and climatological characteristics. Floristic structure of investigated sites were consisting of 151 plant species, including a large number of species of ruderal vegetation.Iako se crvena djetelina prvenstveno koristi za hranidbu mliječnih krava, ona može popraviti strukturu tla, uz pomoć kvržičnih bakterija fiksirati atmosferski dušik i spriječiti eroziju tla. Donedavno je u Hrvatskoj prevladavao tradicionalni uzgoj crvene djeteline. Napuštanje poljoprivredne proizvodnje razlog je procesa pojave sukcesije livada koji može uzrokovati genetsku eroziju i ugroziti opstanak lokalnih populacija crvene djeteline. Utvrđivanje lokacija lokalnih populacija crvene djeteline, prema njihovim ekološkim karakteristikama, moglo bi pomoći u pronalaženju smjera djelovanja u cilju očuvanja biološke raznolikosti vrsta u njenim prirodnim staništima, kao i očuvanja genetskih resursa i njihove uporabe u oplemenjivačkim programima. Cilj ovog istraživanja bio je klasificirati lokacije lokalnih populacija crvene djeteline, koje su pod ekstenzivnom poljoprivrednom proizvodnjom, na području sjeverozapadne Hrvatske na temelju njihovih ekogeografskih karakteristika. Podaci o geografskim, pedološkim i klimatskim karakteristikama i florističkom sastavu prikupljeni na 18 lokacija podvrgnuti su multivarijatnoj analizi. Glavne razlike između lokacija utvrđene su u geografskim, pedološkim i klimatskim karakteristikama. Floristički sastav istraživanih lokacija, čije su lokalne populacije crvene djeteline sastavni dio, sadrži 151 biljnih vrsta, među kojima je veliki broj vrsta ruderalne vegetacije

Content of Mineral N in Soil and Tomato Yields Considering Fertigation and Mulch

The objective of this study was to determine the effect of application of different amounts of N fertilizer added by fertigation and different mulches on the total mineral N in the plough soil layer and yield of tomatoes. The two-year study (2007 and 2009) was conducted on hydromeliorated deep Terra Rossa near Pula. In two-factor experiment, set in a split-plot design, the main factor was N fertilization (NF) in three levels: 60 (NF1), 120 (NF2), and 180 (NF3) kg N ha-1. Subfactor was soil mulch (M), also in three levels: without mulch (WM), straw mulch (SM), and mulch with black polyethylene film (BPM). Different NF significantly affected the amount of N min in the soil. Only in 2009, mulch as well as interaction between NF and DAT had significant impact on the amount of N min in soil. Nitrogen fertilization did not significantly affect the total yields of tomatoes, except the application of NF2 and BPM that generated significantly higher yields of tomatoes in 2007. Recommended technology is application of NF2 and BPM, but with ecological point of view it would be justified to use the nitrogen fertilization with only 60 kg N ha-1

Specified-Purpose Pedologic Map of the Republic of Croatia at the Scale of 1:300 000

Prvi put u Republici Hrvatskoj izrađena je pedološka karta pogodnosti tla za obradu u mjerilu 1:300 000. Nastala je na temelju podataka Osnovne pedološke karte mjerila 1:50 000 i drugih kartografskih prikaza rađenih u posljednjem 30-godišnjem razdoblju. Pedosustavne jedinice procijenjene su prema pogodnosti za obradu po metodi i kriterijima procjene zemljišta FAO. Karta je izrađena u računalnoj tehnologiji u digitalnom obliku s pripadajućom bazom podataka i prva je digitalna karta s tom tematikom u Hrvatskoj. Bazu podataka čine podaci o kartiranim jedinicama tla (pedološkim konturama), te podaci o pedološkim profilima.First time in the Republic of Croatia was worked out soil suitability map for cultivation purposes at the scale of 1:300 000. The map was done according to Basic Soil Map of the Republic of Croatia at the scale of 1:50 000 and many local detailed soil maps worked out last 30 years. The soil mapping units were assessed according to their farming suitability, in accordance with FAO methods and criteria of land evaluation. The map was done by computer technology in the digital form with the corresponding database, and this is the first digital map covering this subject in Croatia. The database consists of all data referring to soil mapping units – pedological contours, and of the data referring to soil profiles

Agroecological conditions of industrial hemp production in the western Pannonian agricultural subregion and fatty acids composition of hemp seed oil

Konoplja se uzgaja širom svijeta i prilagođena je širokom rasponu agroekoloških uvjeta. Međutim visina prinosa i kvaliteta ulja sjemena konoplje ovisi o varijabilnosti agroekoloških uvjeta, kao i o uzgajanom kultivaru i agrotehničkim mjerama uzgoja. Cilj ovoga istraživanja je utvrditi klimatske i pedološke uvjete uzgoja industrijske konoplje sorte Fedora 17 na dva OPG-a na području zapadno Panonske poljoprivredne podregije koja zauzima oko 18,5% od ukupne površine Hrvatske i gdje se nalazi 555.198 ha poljoprivrednog zemljišta. Određen je i sastav masnih kiselina u ulju sjemena konoplje tijekom vegetacijskih godina 2016. i 2017. Pedološke prilike su određene standardnim terenskim i laboratorijskim metodama, klimatske značajke temeljem analize 30 godišnjeg (1986-2015) niza klimatskih podataka, dok je sastav masnih kiselina u ulju određen plinskom kromatografijom nakon hladnog prešanja sjemena konoplje. Rezultati ukazuju na veliku heterogenost pedoloških prilika na istraživanim lokacijama, dok su se klimatski uvjeti tijekom vegetacijskog razdoblja konoplje značajno razlikovali samo u prosječnim temperaturama zraka. Heterogenost agroekoloških uvjeta, prvenstveno fizikalnih značajki tla, je utjecala na visinu prinosa sjemena konoplje, koji je ovisno o lokaciji i godini istraživanja varirao od 350-1200 kg/ha, ali nije utjecala na sastav masnih kiselina u ulju koje je bilo zadovoljavajuće kvalitete na obje lokacije u obje godine istraživanja.Hemp is cultivated worldwide and it is adapted to a wide range of agroecological conditions. However, the yield level and the hemp seed oil quality depend on their variability, as well as on cultivars and agrotechnical cultivation measures. The objective of this study was determined climatic and pedological conditions of industrial hemp production, cultivar Fedora 17, on two family farms in the area of the western Pannonian agricultural subregion, which occupies about 18.5% of the total area of the Republic of Croatia where 555,198 ha agricultural land is located. It was determined the composition of fatty acids in the hemp seed oil grown during the investigation years 2016 and 2017. Pedological conditions were determined by standard field and laboratory methods, climatic features based on 30-yr analysis (19862015) of climatic data while the composition of fatty acid in hemp seed oil is determined by gas chromatography after seeds cold pressing. Results indicate a great heterogeneity of the pedological conditions at the investigated locations, while climatic conditions during the hemp vegetation differed significantly only in average air temperatures. The heterogeneity of the agroecological conditions, primarily pedophysical characteristics, influenced on hemp seed yield which depending on the location and year in which the study was conducted ranged from 350-1,200 kg/ha, but not infuenced on fatty acids composition in the oil that was of satisfactory quality at both locations and in both years of investigations