Varstvo ekosistemov / Protecting ecosystems

author: Gorazd Urbanič, Biotechnical Faculty, University of Ljubljana
produced by: Videofon d.o.o.
published: June 30, 2010,   recorded: October 2008,   views: 3521
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Varstvo ekosistemov s trajnostno rabo predstavlja nov pristop varstva, ki poleg ohranjanja vključuje tudi revitalizacije (izboljšave) ekosistemov in rabo, ki bo trajnostna.

Potrebe po varovanju so se pojavile, ko smo začeli okolje intenzivno spreminjati, kar vključuje tako onesnaževanje kot fi zično spreminjanje. Površina zaščitenih območij je v devetdesetih letih 20. stoletja dosegala manj kot 4 % svetovnega ozemlja. Tudi zato so v razvitejših delih sveta sprevideli, da zavarovanje le nekaterih območij ob trenutnem trendu spreminjanja narave ne bo omogočilo trajnostnega razvoja. Zato so si za izziv postavili najprej pripraviti smernice in kasneje tudi načrte upravljanja, ki bodo omogočali trajnostno rabo ekosistemov. Naravni ekosistemi so ogroženi zaradi vpliva delovanja človeka, ki izhaja predvsem iz rasti prebivalstva in njegovih potreb. Najpomembnejše obremenitve, ki jih povzročamo in s katerimi vplivamo na ekosisteme, so sprememba habitata, fragmentacija habitata, čezmerno izkoriščanje ekosistemov in vrst, vnos tujerodnih vrst, onesnaževanje, odvzemi vode in klimatske spremembe. Ob sedanjem trendu zmanjševanja ekosistemske pestrosti celinskih voda in povečevanju pritiskov na ekosisteme bomo kmalu dosegli raven, ki bo skrajno zaskrbljujoča, posledice pa bodo katastrofalne. Tudi zaradi tega potrebujemo ekosistemski pristop varstva. Ekosistemski pristop varstva pomeni upravljanje naravnih dobrin z uporabo sistemsko širokih konceptov, ki zagotavljajo, da so rastline in živali v ekosistemu ohranjene v dobrem stanju v izhodiščnih – naravnih habitatih in delovanje ekosistemov ni moteno. Za uspešno varstvo je zelo pomembno, da pri tem sodelujejo tako država kot tudi regionalna in lokalna oblast. Del ekosistemskega varstva je tudi ekonomija okolja. Vrste, združbe in ekosisteme moramo ovrednotiti, da jih bomo lahko neposredno primerjali z vrednostjo projektov, ki bi povzročili njihovo izginotje.

Koraki v ekosistemskem pristopu varstva so:
1. izbor območja zanimanja oz. ekosistema in vključitev déležnikov;
2. opis značilnosti izhodiščnega (naravnega) ekosistema;
3. opis značilnosti sedanjih ekonomskih, okoljskih in socialnih razmer in trendov;
4. razvoj skupne vizije želenega stanja in določitev okoljskih ciljev;
5. razvoj in implementacija načrta upravljanja;
6. spremljanje stanja in vrednotenje rezultatov;
7. dopolnitev načrta upravljanja oz. ukrepanje, če je treba.

Varujemo lahko primarne – naravne ali sekundarne – delno spremenjene ekosisteme. Naravni ekosistemi, ki jih najdemo na določenem območju, so rezultat delovanja naravnih abiotskih in biotskih dejavnikov in so optimalna rešitev. Za varovanje spremenjenih ekosistemov se po navadi odločimo takrat, ko od teh ekosistemov koristimo posebne usluge (npr. pridobivanje električne energije). Če ekosistemi ne dosegajo želenega stanja, ekosistem obnovimo. Opravimo lahko popolno obnovitev (renaturacijo) ekosistema ali vzpostavimo le stanje, podobno izhodiščnemu, in opravimo izboljšanje (rehabilitacijo) ekosistema. Ko na degradirano območje naselimo povsem drugačno združbo, opravimo nadomestitev. Ker je dojemanje ekosistemov in ekosistemskih uslug različno, rabimo zakonodajo. Zakonodaja, ki vključuje ekosistemski pristop varstva, omogoča izkoriščanje ekosistemskih uslug, vendar le tistih, ki bodo ohranjale osnovno zgradbo in delovanje naravnega ekosistema. V Sloveniji imamo temeljna izhodišča varstva okolja vključena že v ustavo Republike Slovenije, ki nam nalaga skrb za ohranjanje naravnega bogastva in možnosti za skladen civilizacijski in družbeni razvoj. Ekosistemski pristop varstva je vključen tudi v politiko Evropske unije. Vendar na evropski ravni sprejemamo le smernice, države članice pa morajo v skladu s smernicami ukrepe za doseganje ciljev direktiv popolno in pravilno prenesti v svojo zakonodajo. V Sloveniji imamo več zakonov, ki neposredno obravnavajo varstvo ekosistemov. To so Zakon o varstvu okolja, Zakon o ohranjanju narave, Zakon o gozdovih, Zakon o kmetijskih zemljiščih in Zakon o vodah. Poleg zakonov smo sprejeli tudi številne podzakonske akte, kot so uredbe in predpisi, ki podrobneje določajo pravila varstva in upravljanja ekosistemov. Zakon o varstvu okolja je krovni zakon, ki ureja varstvo okolja pred obremenjevanjem kot temeljni pogoj za trajnostni razvoj. Namen varstva okolja je spodbujanje in usmerjanje takšnega družbenega razvoja, ki omogoča dolgoročne pogoje za človekovo zdravje, počutje in kakovost njegovega življenja ter ohranjanje biotske raznovrstnosti. Zakon o ohranjanju narave določa ukrepe ohranjanja biotske raznovrstnosti in sistem varstva naravnih vrednot z namenom prispevati k ohranjanju narave. Vendar pa zakon ne predvideva le ohranjanja, kot bi lahko sklepali iz imena, ampak v primerih spremenjene naravne vrednote predvideva najprej vzpostavljanje izhodiščnega stanja in šele nato ohranjanje. Ekosistemska raven je v zakonu zajeta tako v biotski raznovrstnosti (raznovrstnost ekosistemov) kot tudi v naravnih vrednotah. Za ohranjanje biodiverzitete na ekosistemski ravni zakon nalaga ohranitev habitatnih tipov, določitev ekološko pomembnih območij, določitev posebnih varstvenih območij – območja Natura 2000 in varstvo naravnih vrednot.

Zakon o gozdovih predvideva nacionalni gozdni program, v katerem se določijo nacionalna politika trajnostnega, sonaravnega in večnamenskega gospodarjenja z gozdovi in usmeritve za ohranitev in razvoj gozdov ter pogoji za njihovo izkoriščanje oziroma večnamensko rabo. Cilj zakona je trajnostno upravljanje gozdov ter ohranitev in izboljšanje življenjskih razmer za živali, ki prosto živijo v gozdu. Za doseganje ciljev uporabljamo gozdnogospodarske in lovskoupravljavske načrte območij. Kljub temu da skoraj 60 % Slovenije poraščajo gozdovi, dejanska drevesna sestava obstoječih gozdov v precejšnji meri odstopa od potencialne vegetacije. Na mnogih območjih so prevladujoče vrste, ki so bile tja zasajene ali so posledica gospodarjenja z gozdovi v preteklosti. S tem smo v mnogih primerih gozdne ekosisteme vsaj delno spremenili. Kmetijska zemljišča so močno degradirani gozdni ekosistemi, ki so spremenjeni zaradi kmetijske rabe. Zakon o kmetijskih zemljiščih ureja tako rabo kmetijskih zemljišč kot njihovo varstvo predvsem pred onesnaževanjem. Ekosistemski pristop varstva je vključen tudi v politiko Evropske unije do voda. Leta 2000 je bila objavljena t. i. Vodna direktiva – Direktiva 2000/60/ES, ki smo jo v slovensko zakonodajo prenesli z Zakonom o vodah. Izhodišče za upravljanje voda je določitev t. i. za tip značilnih referenčnih razmer, pri čemer v izhodišče postavimo naravne razmere in jih opišemo s štirimi skupinami organizmov: fi toplanktonom, fi tobentosom in makrofi ti, bentoškimi nevretenčarji ter ribami. Na vseh teh vodah lahko izkoriščamo različne ekosistemske usluge, vendar le v taki meri, da bistveno ne poslabšamo stanja voda. Vsaka država Evropske unije mora zagotoviti doseganje dobrega ekološkega stanja vseh površinskih voda do leta 2015. Kljub temu da je v Vodni direktivi postavljeno v izhodišče naravno stanje, pa direktiva dopušča tudi izjeme. Vodnim telesom z rabo, ki je za državo ekonomsko pomembna (npr. hidroelektrarne, zajetja pitne vode), kot izhodišče ne določimo naravnih razmer, ampak razmere, ki so optimalne ob obstoječi rabi. V teh primerih varujemo sekundarne ekosisteme. Ekosistemsko varstvo je kompleksen proces, v katerem se soočajo različni interesi. Pogosto lahko trajnostno rešitev dobimo le s širokim soglasjem.


Ecosystem protection by sustainable use is a new approach to environment protection. Beside ecosystem conservation, this approach includes ecosystem revitalization (improvement) and sustainable use.

The need for protection first arose as the environment was being intensively altered, which includes both pollution and physical alterations. In the 1990s, the total area of protected ecosystems comprised less than 4 % of the Earth’s surface area. This was one of the reasons the developed countries realized that protecting isolated areas with the current trends of changes in nature will not enable sustainable development. They therefore set a goal of preparing directives and after that management plans that will enable sustainable use of ecosystems. Natural ecosystems are endangered as a consequence of human actions that stem mostly from the needs of rapidly growing population. The most important burdens we impose on ecosystems are habitat changes and fragmentation, over exploitation of ecosystems and species, introduction of alien species, pollution, water removal and climate change. With the present-day trend of reducing the diversity of freshwater ecosystems, we will soon reach an alarming level and can expect catastrophic consequences. This is an important reason why an ecosystem approach to protection is imperative. The ecosystem approach signifies management of natural goods by using broad concepts that ensure that plants and animals are kept in good condition in their original (natural) habitats and that ecosystem functioning is not impaired. For protection to be efficient, it is very important to have the cooperation of national, regional and local authorities. Part of ecosystem protection is also environmental economics. Species, communities and ecosystems have to be evaluated so that it is possible to compare them with the value of projects that would cause their loss.

The steps in the ecosystem approach are the following:
1. Selection of the area of interest or ecosystem and inclusion of stake-holders;
2. Description of the original (natural) ecosystem;
3. Description of current economic, environmental and social conditions and trends;
4. Development of joint vision of the desired state and establishment of environmental goals;
5. Development and implementation of the management plan;
6. Monitoring and evaluation of results;
7. Supplementation of the plan or action, if necessary.

The object of protection can be either natural or secondary (partially altered) ecosystems. Natural ecosystems are the result of the functioning of natural abiotic and biotic factors and are the optimum solution in the given environment. The protection of altered ecosystems is usually decided upon when the ecosystems provide us with certain ecosystem services (e.g. obtaining electrical energy). If ecosystems do not reach the desired state, they need to be restored. This can either be complete renaturation of the ecosystem or restoration of the state similar to the original one (ecosystem rehabilitation). When a degraded area is populated with a completely different community, this is called substitution. The perception of ecosystems and ecosystem services is very variable and therefore requires legislation. A legislation that includes the ecosystem approach of protection enables exploitation of ecosystem services, but only those that retain the original structure and function of natural ecosystems. In Slovenia the basic points of environment protection are included in the Constitution of the Republic of Slovenia, which charges us with protecting natural wealth and possibilities for harmonious development of the civilization and society. The ecosystem approach to protection is included also in the politics of the European Union. However, at the European level, only directives are passed and the member countries have to integrate the measures for reaching the goals set by the directives completely and correctly into their own legislation. There are several legal acts in Slovenia that directly deal with the topic of ecosystem protection. These are the Environment Protection Act, the Nature Conservation Act, the Act on Forests, the Agricultural Land Act and the Water Act. Beside these acts, there are also several decrees and regulations that define in more detail the policy of ecosystem protection and management. The Environment Protection Act is the main law that defines protecting the environment form loads as the basic condition for sustainable development. The aim of environment protection is encouraging and directing such a way of social development that enables long-term conditions for human health and quality of life and preservation of biodiversity. The Nature Conservation Act defines the measures for preserving biodiversity and the system of protecting natural values with the intention of contributing to preserving the natural environment. However, despite its name, this law does not only envisage conservation but in the cases of altered natural values requires first the reestablishment of the natural conditions and only then conservation. The ecosystem level in the law is comprised both in the biodiversity (ecosystem diversity) as well as in natural values. For preserving biodiversity on the ecosystem level, the Act dictates the preservation of habitat types, the establishment of ecologically significant sites, the establishment of special protection areas – Natura 2000 sites and the protection of natural values.

The Act on Forests defines the national forest program wherein the national policy of sustainable and multipurpose forest management is delineated, as well as the guidelines for the preservation and development of forests and the terms of their exploitation or multipurpose use. The aims of the Act are sustainable forest management, preservation of forests and amelioration of the living conditions for animals living freely in forests. To achieve these aims, regional forest and hunting management plans are set. Forests grow over almost 60 % of the Slovene territory. Nonetheless, the actual tree composition of these forests is largely different from the potential vegetation. The prevalent species in many areas are those that have been planted or are the consequence of forest management in the past. Many forest ecosystems have been at least partially altered in this way. Farmlands are severely degraded forest ecosystems that had been altered for the purposes of farming. The Agricultural Land Act manages the use of farmlands as well as their protection against pollution. The ecosystem approach to protection is included also in the water policy of the European Union. In the year 2000 the EU passed the Water Framework Directive (Directive 2000/60/EC) which has been incorporated into the Slovene legislation with the Water Act. The starting point of water ecosystem management is the defining of the so-called type specific reference conditions. This is done by starting form natural conditions and describing them with four groups of organisms: phytoplankton, phytobenthos and macrophytes, benthic invertebrates and fi sh. Ecosystem services can be used in all waters but only insofar as they do not significantly impair the conditions of these ecosystems. Each EU member is required to ensure good ecological state of all its surface waters by the year 2015. Although the Water Framework Directive sets the natural conditions as the starting point, it allows for certain exceptions. For water bodies being used in a way that is of national economic importance (e.g. hydroelectric power plants, drinking water impounds) the starting point are not natural conditions, but those that are optimal for the existing use. In these cases, secondary ecosystems are protected. Ecosystem protection is a complex process where different interests are confronted. The sustainable solution can often only be achieved by a wide consensus.

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