Uticaj režima vlaženja na karakteristike staništa hrasta lužnjaka (Quercus robur L.) u Ravnom Sremu

Abstract

Nizijske šume lužnjaka u donjem toku reke Save u Ravnom Sremu izložene su negativnim uticajima, kako prirodnih, tako i antropogenih faktora. Značaj vode kao ekološkog faktora, kako biocenoze, tako i biotopa, ogleda se u oblikovanju nizijskih šuma čijim promenama se narušava ekološka ravnoteža i njihova stabilnost. Rad obuhvata istraživanja uslova staništa sa aspekta nedostatka ili viška vode, koji kao faktor stresa utiče na proces propadanja ekološki značajnih i ekonomski vrednih šuma hrasta lužnjaka u Srbiji. Istraživanjima u ovom radu obuhvaćeni su šumski kompleksi zaštićenih površina od plavnih voda Save - Gornji Srem i Donji Srem, koji se nalazi pod neposrednim uticajem plavljenja. Na istraživanom području Gornjeg Srema, izdvojena su i analizirana četiri tipa zemljišta - tri iz reda hidromorfnih (pseudoglej, fluvisol i humoglej) i jedan koji pripada redu automorfnih zemljišta (černozem). U Donjem Sremu analizirana su dva tipa zemljišta iz reda hidromorfnih zemljišta (fluvisol i humoglej). Osnovni ekološki faktor, sadržaj vode u zemljištu analiziran je preko momentalne vlage, čije su oscilacije date u rasponima vodnih konstanti po tipovima zemljišta. Analizirani su sledeći oblici vode: gravitaciona, lakopristupačna kapilarna voda i teže pristipačna kapilarna voda, kao i nepristupačna voda biljkama. Vreme trajanja pomenutih oblika vode u zemljištu analizirano je tokom vegetacionog perioda (2010-2012. god). Zalihe pojedinih oblika vode (gravitaciona-mokra zona; lakopristupačna-vlažna zona; teže pristupačna-umereno vlažna zona i nepristupačna-suva zona) analizirane su po tipovima zemljišta, odnosno genetskim horizontima i predstavljaju pokazatelj količina raspoložive vode tokom vegetacionog perioda. Na osnovu dobijenih rezultata, utvrđene su promene sadržaja vode u zemljištu, kako tokom vegetacionog perioda iste godine, tako i tokom različitih godina. Morfološka i morfometrijska istraživanja korenovog sistema hrasta lužnjaka ukazuju na zone iz kojih se usvaja voda iz zemljišta, kao i na način njegovog prilagođavanja različitim tipovima zemljišta...

Lowland pedunculate oak forests in lower course of the river Sava in Ravni Srem are under negative influences, not only of natural, but also of anthropogenic factors. Water importance as the ecological factor both of biocenosis and biotope could be recognized during the process of lowland forests forming, whose changes cause disordering of ecological balance and its stability, as well. The paper includes researching of habitat conditions from water lack or excess point of view that as a stressing factor affects degradation of ecologically and economically important forests of pedunculate oak in Serbia. In this paper, there are included forest complexes of areas protected from flooding waters of the river Sava – Gornji Srem and Donji Srem, that is located under direct influence of flooding. In Gornji Srem, there are determined and analyzed four soil types: pseudogley, fluvisol and humogley, that belong to hydromorphic soils, and one that belongs to automorphic soils – chernozem. In Donji Srem, there are analyzed two soils types from hydromorphic class – fluvisol and humogley. Basic ecological factor – water content in the soil – was analyzed due to current humidity, whose changes have been shown in different ranges of water constants for each soil type. Analyzed water forms are: gravity, easily-available, hard-available and unavailable water for the plants. Duration time of mentioned water forms in the soil was analyzed during the vegetation period (2010-2012). Supplies of some water forms (gravity - very wet zone; easily-available – wet zone; hard – available – middle-wet zone; unavailable – dry zone) have been analyzed on the base of soil types (on the base of genetic horizons) and they show quantity of available water during the vegetation period. On the base of obtained results, changes of water content in the soil have been recorded, not only during the vegetation period of the same year, but also during the different years. Morphological and morphometric research of the root system of pedunculate oak show zones from which the water has been adopted, and the way of its adaptability to different soil types, as well. Water content in the soil compared to rainfalls quantity and groundwater level shows that there is no connection between rainfalls quantity and current humidity content in the soil during the vegetation period...