Članak istražuje određene aspekte značenja i konceptualizacije fenomena kompleksnosti kao složene cjeline senzacija koje pridonose uspješnosti otvorenih prostora. Problematika rada obuhvatila je ...kritičko preispitivanje definiranja i dimenzija procjenjivanja složenosti otvorenih prostora te preispitivanje indikatora „optimalne razine složenosti“ parkova. Rad je uključio kombiniranje tri metode - strukture analize složenosti, metodu opservacije uz metodu brojanja te anketiranje. Metode su primijenjene na istom području rada – dva suvremena parka, a korisnici tih parkova našli su se u trojnoj ulozi – kao objekt promatranja i metode brojanja te kao ispitanici u anketnoj metodi. Provedeno istraživanje jasno ukazuje na to da je koncept složenosti važna komponenta uspješnosti parkova te da su složeniji dijelovi parkova posjećeniji i više cijenjeni od onih manje složenih. Također, pokazalo se da je za cjelovito praćenje kompleksnosti otvorenih prostora potrebno okupljati i vizualne i funkcionalne indikatore složenosti kao i dinamične dimenzije složenosti otvorenih prostora. Pri tome smatramo, a i rezultati tako govore, da je kod oblikovanja otvorenih prostora stanje velike složenosti optimalnije od stanja srednje ili male složenosti parkova.
Task difficulty is an important but complex phenomenon in Applied Linguistics, for which there is relatively little empirical research. This article discusses approaches to defining task difficulty ...and focuses on objective task difficulty derived from ratings of performances and on difficulty derived from an error count in the performances, thus taking errors as indicators of writing task difficulty. Errors are described in terms of the Scope–Substance error taxonomy in writing performances from the Slovene General Matura examination in English. The most frequent errors are located at word and phrase level. Generally, error frequency decreases as writing proficiency increases, but some error types do not conform to this trend. This is the case for punctuation errors, which gain prominence at higher levels of mastery. The results of this study are relevant for assessment, particularly for rating scale development or revision, and for rater training. They are equally relevant for teaching, since knowing sources of difficulty in tasks is a prerequisite for effective pedagogical action. More generally, if applied to performances based on a wider range of tasks, viewing errors as indicators of difficulty can lead to a better understanding of difficulty‐generating task features.
Povzetek
Težavnost nalog je pomemben, a zapleten pojav v uporabnem jezikoslovju, o katerem je razmeroma malo empiričnih raziskav. Prispevek obravnava pristope k opredeljevanju zahtevnosti nalog pri preverjanju pisnega sporočanja. Osredinjen je na njihovo objektivno zahtevnost, ki izhaja iz točkovnih ocen pisnih izdelkov in iz števila napak v izdelkih, kar pomeni, da napake obravnava kot kazalec zahtevnosti nalog. Napake opredeli po taksonomiji obseg‐vsebina in jo uporabi za ocenjevanje pisnih izdelkov na izpitu iz angleščine na slovenski splošni maturi. Najpogostejše napake se pojavljajo na ravni besed in besednih zvez; večinoma se njihova pogostnost zmanjša z naraščanjem pisne zmožnosti, vendar nekatere vrste napak ne sledijo temu trendu. Tak je primer napak v rabi ločil, ki so pogostejše na višjih ravneh znanja. Rezultati študije so pomembni za ocenjevanje, predvsem za razvoj in prenovo ocenjevalnih lestvic, pa tudi za usposabljanje ocenjevalcev. Dognanja so pomembna tudi za poučevanje, saj je razumevanje razlogov za zahtevnost predpogoj za učinkovito pedagoško delo. Širše gledano lahko napake uporabimo kot kazalec zahtevnosti tudi pri drugih vrstah nalog in s tem izboljšamo prepoznavanje in razumevanje tistih lastnosti nalog, ki prispevajo k njihovi zahtevnosti.
Already for nearly three decades, Mass Customization (MC) has been described as a viable business model for companies in diverse sectors. Nonetheless, the introduction and the successful operation of ...an MCapproachis a challenging endeavor for companies of all sizes. In this article,special attention is givento small and medium-sized enterprises (SMEs), which increasinglycollaborate in networks to successfully develop complex, mass-customized products. Whilecollaboration allows for pooling several areas of expertise,the cross-organizational development poses challenges in manifold regards. To study these challenges, we set up a network business process model developed with four SMEs from the German high-tech textile industry. Based on the current literature on capabilities for MC, we evaluate the challenges of MC in SME networks detected in our network business processmodel to underpin the need for further research.In our study, we detail the conceptualanalysisof such network-based scenarios along our process model for three focal areas: (1) co-creation, (2) solution space development, and (3) information systemdesign. We construe the need for further research and derive implications for both academia and practice.
Specifične, kompleksne i problematične situacije koje se javljaju u postupku ovrhe na brodu radi naplate novčane tražbine zahtijevaju podrobniju analizu svih problematičnih pitanja.Takve situacije su ...odraz nedovoljno utvrđenih odredbi, odnosno nepostojećih odredbi koje je zakonodavac propustio utvrditi, a reguliraju ovakav postupak naplate tražbina. Intencija ovoga rada je unificirani i sustavni prikaz takve problematike kroz sve faze postupka. U provedbi ovrhe su evidentni složeni međusobni odnosi neposrednih sudionika na koje se odnose uzrok i posljedice postupka, te posrednih sudionika koji imaju neki pravni interes, pa na njih mogu (ali i ne moraju) utjecati posljedice postupka. Pri tome valja naglasiti da se sustavno iznose pravne dvojbe o statusu neposrednih i posrednih sudionika postupka, te problematika postupovnih radnji cjelokupnog postupka, a ne samo faze provedbe ovrhe na brodu. Svaka faza postupka je opterećena manjom ili većom problematikom, bez iznimke, od podnošenja prijedloga za ovrhu do naplate vjerovnika. Isto tako, mogući su slučajevi zlonamjernih raspoložbi s krajnjim ciljem da se obustavi ovrha i spriječi prodaja broda koji je predmet ovrhe. Zakonodavac je propustio kvalitetno utvrditi ovu materiju, pa rješenja nekih inozemnih pravnih sustava, koja se odnose na postupak ovrhe, mogu poslužiti kao putokaz u nadopuni postojećih odredbi Pomorskog zakonika.
Specific, complex and problematic situations that may arise in a foreclosure procedure to collect a cash claim require a more thorough analysis of all problematic issues. Such situations are a reflection of insufficiently defined provisions that is nonexistent provisions that the legislature has failed to determine, and regulate this procedure for collecting claims. The intention of this paper is to present a unified and systematic account of such issues throughout all stages of the procedure. This can also be compounded by the complex interrelationships between the direct participants involved in the cause and effect of the proceeding, as well as the indirect participants who have a legal interest, and may and may not be affected by the consequences of the proceeding. It should be emphasized that legal doubts are systematically raised about the status of direct and indirect participants in the procedure, as well as the issues of procedural actions of the whole procedure, and not just the enforcement phase on board. Each stage of the proceedings is burdened with more or less problems, without exception, from the submission of a writ of foreclosure to the payment of creditors. Likewise, there may be cases of malicious mischief with the ultimate goal of suspending foreclosure and preventing the sale of the foreclosed ship.The legislature has failed to qualitatively determine this matter, so the solutions of some foreign legal systems, related to the enforcement procedure on board, can serve as a guide in addition to the existing provisions of the Maritime Code.
Istraživanje predstavlja teorijsku i empirijsku analizu birokratskih i ne-birokratskih alata za rješavanje problema u organizacijama koje se smatraju kompleksnim adaptivnim sustavima. Polazeći od ...Stacyine teorije kreativne kompleksnosti, osmislili smo istraživački okvir sastavljen od pet indikatora (dimenzija): dezintegracija, nepravilnost, nestabilnost, disrupcija te devijacija (svaki od indikatora dalje je operacionaliziran u šest pitanja u upitniku). Imajući na umu istraživačku hipotezu, analizirali smo sklonost donošenju odluka slijeđenjem birokratske logike (linearnoga okruženja) s jedne strane, te logike kreativne kompleksnosti s druge. Razina sklonosti analizirana je u usporedbi s učinkovitošću rješavanja problema korištenjem metode ponovljene mjere MANOVA – (intersubjektivni faktor – UČINAK: 1. uspješan, 2. neuspješan). Sudionici istraživanja bila su 743 zaposlenika različitih organizacija. U istraživanju je korištena metoda upitnika K-T-1. Rezultati analize pokazali su da se stupanj uspjeha u rješavanju problema značajno razlikuje u tri dimenzije: nepravilnost, nestabilnost i devijacija. Veća sklonost kreativnoj kompleksnosti pronađena je u dvije dimenzije: devijacija i pravilnost. Veći uspjeh u rješavanju problema slijedeći birokratsku logiku pronađen je u dimenziji nestabilnost.
Spoznanje, da je družba postala kompleksna, pomeni, da resnica o družbenih zadevah kot o tem, kaj je skupno dobro ali kako uspešno je njegovo doseganje, ni več ena sama, tista na oblasti, ampak o ...pomembnih stvareh obstaja več do- bro utemeljenih in enako veljavnih resnic. Zadeve iz domene javnega upravljanja so kompleksne, zato različni pogledi nimajo skupnega imenovalca in jih je treba obravnavati kot nesomerne oziroma globoke in nepremostljive. Družbene pojave je zato treba proučevati v zlatem rezu njihove dvojnosti, razpenjajoči se med razlago primarnih pomenov, ki so za sistem konstitutivni, vendar na nesomeren in razdvajajoč način, in razlago sekundarnih pomenov, ki edini podajajo celovit pogled na vrednoteni pojav, vendar le v vsebinah, ki za nikogar niso bistvene.
Spoznanje, da je družba postala kompleksna, pomeni, da resnica o družbenih zadevah, kot o tem, kaj je skupno dobro ali kako uspešno je njegovo doseganje, ni več ena sama, tista na oblasti, ampak o ...pomembnih stvareh obstaja več dobro utemeljenih in enako veljavnih resnic. Zadeve iz domene javnega upravljanja so kompleksne, zato različni pogledi nimajo skupnega imenovalca in jih je treba obravnavati kot nesomerne oziroma globoke in nepremostljive. Družbene pojave je zato treba proučiti v zlatem rezu njihove dvojnosti, razpenjajoči se med razlago primarnih pomenov, ki so za sistem konstitutivni, vendar na nesomeren in razdvajajoč način, in razlago sekundarnih pomenov, ki edini podajo celovit pogled na vrednoteni pojav, vendar le v vsebinah, ki za nikogar niso bistvene.
Provider: - Institution: - Data provided by Europeana Collections- Previous studies have found that during aging a large number of biological structures such as tissues and organs loses its ...complexity and that such loss leads to reduced ability to adapt to physiological stress. However, so far there is no information on whether similar structural changes occur in individual cells and their genetic material. Structural complexity can be quantified in several ways. Recent studies have determined that the chromatin, as well as many other biological structures exhibit fractal characteristics in their morphology. The concept of fractals is based on the principle of self-similarity, or the fact that the lower parts of a physical or biological system resemble the system as a whole. The complexity of fractal structures can be measured by determining the fractal dimension and lacunarity as the two most important parameters of fractal analysis. In addition to the fractal analysis, textural analysis as a method is also frequently used. Textural analysis can determine the parameters of textural heterogeneity and disorganization (i.e. entropy) of biological structures. In our study, on the mouse experimental model, we studied age-related changes in chromatin structural complexity in the total of 10 cell populations in the thymus, spleen, kidney and liver. Also, we described changes in the complexity of the nuclear structure in a cell culture after the induction of DNA damage by UV radiation. The study was conducted on 80 male mice, originating from the experimental animal vivarium of the Institute of Medical Physiology, Faculty of Medicine, Belgrade. The pilot study was conducted on a group of 16 mice in which the first animal was a newborn, and each of the following animals was 30 days older than the previous one (the oldest animals were 450 days old). The main part of the study in laboratory animals, was conducted on a total of 64 animals which were divided into 8 age groups (n = 8): 0, 10, 20, 30, 120, 210, 300 and 390 days old. The experimental protocol was designed according to the following procedure: measurement of body mass, sacrifice by cervical dislocation, extirpation of the thymus, spleen, kidney and liver, fixation in Carnoy fixative, embedding in Paraplast, making of slices of thickness 5 microns. Slices of all four organs were then stained by hematoxylin / eosin and toluidine blue technique. Spleen and thymus was further stained by Gimza technique and kidney tissue with Azo carmine aniline blue (AZAN) method. After staining, we made digital micrographs of the tissues using the Olympus C-5060 Wide Zoom camera mounted on Olympus BX41 light microscope (1000x magnification, 100x immersion lens). Digital micrographs of tissue were made and processed similarly to our previous study (Pantic & Pantic, 2012). For all examined tissues, with the help of special software ImageJ of the National Institutes of Health (USA) and integrated plugins, we determined the mean value of fractal dimension, lacunarity, entropy, variance, angular second moment, textural contrast, textural correlation and inverse difference moment. We measured the structural complexity of chromatin in the following cell populations stained with hematoxylin / eosin technique: in thymus cortical and medullar lymphocytes and stromal cells; spleen follicular lymphocytes, and spleen erythroid precursor cells of the subcapsulary haematopoietic tissue; hepatocytes in the liver; kidney cells of proximal and distal tubules , collecting duct cells as well as macula densa cells. Analysis of individual nuclei was performed on the model of a similar protocol described in our previous studies (Pantic et al. 2012a, Pantic et al. 2012b). In the in vitro part of the study, cell line U251 was treated with UVB rays of wavelength 312 nm with a total duration of 15 minutes. A sample of 32 individual cells (paired sample) was monitored in 12 time points: before UV treatment, immediately after UV treatment, and 30min, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h and 5h after the treatment. The first time point (immediately before UV treatment) was the control. With the help of ImageJ software for each cell and its nucleus at each time point the following parameters were determined: fractal dimension, lakunarnosti, entropy, angular second moment, textural contrasts, textural correlation, variance and inverse difference moment, in accordance with the above text. The results of our study indicate that the fractal complexity of nuclear chromatin decreases in postnatal development and aging in the cell populations of cortical and medullar thymic lymphocytes, epithelial cells of the proximal renal tubules, macula densa cells and in hepatocytes in the liver. Disorder of nuclear chromatin in spleen erythroid precursor cells, measured by textural entropy increased with age. In postnatal development and aging significant reduction of tissue architecture complexity (measured by fractal dimension) was detected in the cortex and medulla of thymus, the cortex and medulla of the kidney, spleen hematopoietic tissue and liver lobuluses. The fractal dimension of tissue architecture was significantly correlated with the fractal dimension of chromatin in most examined tissues, and cell populations. After the induction of DNA damage in vitro, in cell culture, there was a significant decrease in cellular fractal dimension and chromatin lacunarity. These findings indicate that the intrinsic factors associated with the aging of cells, such as the accumulation of DNA damage and changes in the epigenetic regulation of chromatin play an important role in the aging of the investigated cell populations and tissues.- Prethodne studije su utvrdile da tokom starenja veliki broj bioloških struktura kao što su tkiva i organi gubi svoju kompleksnost i da takav gubitak vodi smanjenoj sposobnosti adaptacije na fiziološki stres. Međutim, za sada nema podataka da li se slične strukturne promene dešavaju na individualnim ćelijama i njihovom genetskom materijalu. Strukturna kompleksnost se može kvantifikovati na nekoliko načina. Skorašnje studije su utvrdile da hromatin, kao i mnoge druge biološke strukture u svojoj morfologiji ispoljavaju karakteristike fraktala. Koncept fraktala se u osnovi bazira na principu samosličnosti, odnosno na činjenici da manji delovi nekog fizičkog ili biološkog sistema nalikuju sistemu kao celini. Kompleksnost fraktalnih struktura se može meriti određivanjem fraktalne dimenzije i lakunarnosti kao dva najznačajnija parametra fraktalne analize. Kao dodatak fraktalnoj analizi, danas se često koristi i teksturalna analiza uz pomoć koje se mogu odrediti parametri teksturalne heterogenosti i neuređenosti biološke strukture kao što je entropija. U našoj studiji, na mišijem eksperimentalnom modelu, ispitivane su starosne promene u strukturnoj kompleksnosti nukleusnog hromatina na ukupno 10 ćelijskih populacija u timusu, slezini, bubregu i jetri. Takođe su opisane promene u kompleksnosti nukleusne strukture na kulturi ćelija nakon indukcije DNK oštećenja UV zračenjem. Istraživanje je obavljeno na 80 miševa muškog pola, poreklom iz Vivarijuma za eksperimentalne životinje Instituta za Medicinsku fiziologiju Medicinskog fakulteta u Beogradu. Pilot istraživanje je obavljeno na grupi od 16 miševa u kojoj je prva životinja bila novorođena, a svaka sledeća životinja je bila 30 dana starija od prethodne (najstarija životinja je bila stara 450 dana). Glavni deo istraživanja na eksperimentalnim životinjama je sproveden na ukupno 64 životinje podeljene u 8 starosnih grupa (n=8): 0, 10, 20, 30, 120, 210, 300 i 390 dana. Eksperimentalni protokol je dizajniran po sledećoj proceduri: merenje telesne mase, žrtvovanje životinja cervikalnom dislokacijom, ekstirpacija timusa, slezine, bubrega i jetre, fiksiranje u Carnoy fiksativu, kalupljenje u Paraplastu, pravljenje isečaka debljine 5 μm. Isečci tkiva sva četiri organa su potom obojeni tehnikama Hematoksilin/Eozin i Toluidin plavo. Tkivo slezine i timusa je dodatno obojeno Gimza metodom, a tkivo bubrega Azo carmine aniline blue (AZAN) metodom. Nakon bojenja, pristupilo se pravljenju digitalnih mikrografa tkiva uz pomoć Olympus C-5060 Wide Zoom kamere postavljene na Olympus BX41 svetlosni mikroskop (uveličanje 1000x, imerzioni objektiv 100x). Digitalni mikrografi tkiva su napravljeni i obrađeni po uzoru na našu prethodnu studiju (Pantic & Pantic, 2012). Za svako ispitivano tkivo, uz pomoć specijalnog softvera ImageJ Nacionalnog instituta za zdravlje (SAD) i specijalnih integrisanih podprograma određena je srednja vrednost fraktalne dimenzije, lakunarnosti, entropije, varijanse, angularnog drugog momenta, teksturalnog kontrasta, teksturalne korelacije i inverznog momenta razlike. Za merenje strukturne kompleksnosti hromatina korišćene su sledeće ćelijske populacije obojene hematoksilin/eozin tehnikom: u timusu kortikalni i medularni timociti i stromalne ćelije; u slezini limfociti folikula, i eritroidne prekurzorske ćelije subkapsularnog hematopoeznog tkiva; u jetri hepatociti; u bubregu ćelije proksimalnih i distalnih tubula, ćelije sabirnih kanalića kao i ćelije macule dense. Analiza pojedinačnih jedara je obavljena po uzoru na sličan protokol opisan u našim prethodnim studijama (Pantic et al. 2012a, Pantic et al. 2012b). U in vitro delu studije ćelije linije U251 su tretirane UVB zracima talasne dužine 312 nm u ukupnom trajanju od 15 minuta. Uzorak od 32 individualne ćelije (vezani uzorak) je praćen kroz 12 vremenskih tačaka: pre UV tretmana, odmah nakon UV tretmana, kao i 30min, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h i 5h nakon tretmana. Prva vremenska tačka (neposredno pre UV tretmana) predstavljala je kontrolu. Uz pomoć ImageJ softvera za svaku ćeliju i njeno jedro u svakoj vremenskoj tački određena je vrednost fraktalne dimenzije, lakunarnosti, entropije, angularnog drugog momenta, teksturalnog kontrasta, teksturalne korelacije, varijanse i inverznog momenta ra
The goal of this work is to present the application of system dynamics and system thinking, as well as the advantages and possible defects of this analytic approach, in order to improve the analysis ...of complex systems such as population and, thereby, to monitor more effectively the underlying causes of migrations. This methodology has long been present in interdisciplinary scientific circles, but its scientific contribution has not been sufficiently applied in analysis practice in Croatia. Namely, the major part of system analysis is focused on detailed complexity rather than on dynamic complexity. Generally, the science of complexity deals with emergence, innovation, learning and adaptation. Complexity is viewed according to the number of system components, or through a number of combinations that must be continually analyzed in order to understand and consequently provide adequate decisions. Simulations containing thousands of variables and complex arrays of details distract overall attention from the basic cause patterns and key inter-relations emerging and prevailing within an analyzed population. Systems thinking offers a holistic and integral perspective for observation of the world.
Provider: - Institution: - Data provided by Europeana Collections- Agricultural intensification and associated farming practices are among the most significant human impacts on the global ...environment. Increase in agricultural land-use area and the intensification of crop management are causing numerous environmental problems, including loss of biodiversity and degradation of some key ecosystem services, such as biological control. Numerous studies have emphasized the importance of landscape scale effects in these processes. To determine how agricultural intensification affects agrobiodiversity and accompanied ecological service (biological control), we examined effects of key landscape features on aphid–parasitoid complex in winter wheat agroecosystems in Pančevački rit region. Study was organized in three parts. Aim of the first part was to determine effect of landscape compositional heterogeneity defined through proportion of crop vs. non-crop land in landscape sectors. Two broadly contrasting classes were selected: complex landscapes, characterized by more than 50% of non-crop land cover (forests, fallows, pastures, hedgerows and shrubs), and simple landscapes, with much less than 30% of non-crop land. Total of 50 landscape sectors were sampled in course of four years (2008-2011). In the second part of the study, effects of configurational landscape heterogeneity of crop habitats were tested through contrasting landscape sectors dominated by small fields (field size averaging less than 3 ha) and landscape sectors dominated by large fields (field size averaging more than 20 ha). Total of 24 sectors were sampled in two years (2008-2009). In the third part, aim was to analyze edge effects of field margin types on aphid–parasitoid interactions. Two markedly different margin types were selected: one bordering on irrigation canal with permanent semi-natural shrub vegetation, and the other close to service road without semi-natural vegetation. Total of 12 fields were sampled in two years (2008-2009). Additionally, changes in aphid population growth and parasitism rates between phases were monitored to determine parasitism threshold value for effective biological control. In total, 4 aphid species, 7 parasitoid species and 9 hyperparasitoid species were found. Results show that complex landscapes with higher proportion of non-crop land support larger aphid populations and higher parasitism rates, as well as higher diversity of both parasitoids and hyperparasitoids. Second part of the study revealed non-significant landscape effects on overall aphid abundances and parasitism rates. Contrary to initial expectation, no differences in analyzed parameters between small- and large-field landscapes were detected. Only detected effect was differential change during season in aphid population growth (stronger in small-field landscapes) and in parasitism rate (higher in large-field landscapes). Results of the third part show that larger aphid population are found near field margin, especially near margin bordering on permanent semi-natural shrub vegetation. Contrary to initial expectations, field margin type had no effect on parasitoids. Parasitism threshold value for effective biological control was estimated to be in 19-27% range. Values above this range regularly resulted in drop of aphid population densities. It was observed that there is temporal variability in the strength of landscape effects on aphid–parasitoids complex, but that general trends and conclusion how different landscape features affect model system can be proposed.- Intenzifikacija poljoprivrede predstavlja jedan od globalnih procesa sa izrazito negativnim efektima na biodiverzitet. Održavanje visokog nivoa biodiverziteta neophodno je za obezbeđivanje ekosistemskih usluga, od kojih su neke, poput biološke kontrole štetočina, od velike važnosti u agroekosistemima. Rezultati sve većeg broja studija ukazuju na to da elementi i karakteristike kompozicije i konfiguracije poljoprivrednih predela imaju ključnu ulogu u očuvanju, odnosno, narušavanju agrobiodiverziteta. Predeono-ekološki pristup u agroekologiji proučava uticaj različitih obrazaca i procesa u savremenoj poljoprivrednoj praksi na mehanizme degradacije biodiverziteta i gubitak funkcionalnosti njegovih komponenti. Posebno je značajno upoznati obrazce i trendove u trofičkim interakcijama koje povezuju intenzivno korišćene agroekosisteme i okolna poluprirodna i prirodna staništa. U ovom istraživanju, analizirani su efekti predeonih karakteristika na diverzitet i interakcije model sistema žitne vaši – parazitoidi na području Pančevačkog rita. Istraživanje je bilo podeljeno u tri dela kako bi se ispitali efekti tri različita aspekta predeone heterogenosti. Cilj prvog dela istraživanja bio je određivanje efekta predeone kompleksnosti izražene preko procenta prirodnih i poluprirodnih staništa (heterogenost tipova staništa) na model sistem. Odabrane su dve jasno diferencirane kategorije predela: 1) kompleksni predeli (>50% poluprirodnih staništa) i 2) jednostavni predeli ( 20 ha). Analizirano je 24 predeona sektora u toku dve godine (2008-2009). Treći deo bio je fokusiran na određivanje efekata različitog tipa ivice polja na model sistem. Kontrastirana su dva tipa ivice polja: 1) ivica sa poluprirodnom vegetacijom i 2) ivica bez poluprirodne vegetacije. Analizirano je 12 predeonih sektora u toku dve godine (2008-2009). Dodatno, analizirana je promena brojnosti biljnih vašiju tokom sezona sa namerom da se odredi nivo parazitiranosti koji odgovara efektu uspešne biološke kontrole. U toku celokupnog istraživanja zabeležene su 4 vrste biljnih vašiju, 7 vrsta parazitoida i 9 vrsta hiperparazitoida. Rezultati prvog dela istraživanja ukazuju na to da kompleksni predeli koji sadrže veći procenat prirodnih i poluprirodnih staništa podržavaju veću brojnost biljnih vašiju kao i da imaju veći procenat parazitiranosti, diverzitet parazitoida i diverzitet hiperparazitoida. Uočena povećana brojnost biljnih vašiju u kompleksnim predelima je u suprotnosti sa početnim očekivanjima, ali je potvrđeno da kompleksni predeli podržavaju veću uspešnost parazitoida. Rezultati drugog dela istraživanja pokazuju da ne postoji jasno izražen efekat predeone kompleksnosti izražene preko veličine pojedinačnih polja na proučavani model sistem. Suprotno očekivanjima, nije uočena razlika u brojnosti biljnih vašiju i procentu parazitiranosti između predela sa malim i predela sa velikim poljima. Razlika je uočena jedino u promeni brojnosti biljnih vašiju i procentu parazitiranosti između faza generalno i između faza u zavisnosti od predela što ukazuje da je efekat biološke kontrole izraženiji u jednostavnim predelima sa velikim poljima, a da povećavanju brojnosti biljnih vašiju pogoduju kompleksni predeli sa malim poljima. Rezultati trećeg dela pokazuju da je brojnost biljnih vašiju veća na ivici polja, posebno na ivici sa poluprirodnom vegetacijom, a da tip ivice polja nema nikakav efekat na parazitiranost. Takođe, diverzitet parazitoida nije bio značajno različit u odnosu na tip i udaljenost od ivice polja. Procenjeni nivoi parazitiranosti koji odgovaraju stagnaciji brojnosti biljnih vašiju između faza ukazuju na to da se efekat uspešne biološke kontrole pojavljuje u intervalu 19-27% parazitiranosti. Primećeno je da postoji varijabilnost u stepenu ispoljavanja efekata predela na model sistem na nivou godina, ali da se određeni generalni trendovi mogu uočiti.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
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