http://www.uni-koblenz.de/~odsbcg/baeume97/bsterb.htm
Forest-dies or " new forest damage "
Martina Keber
Introduction
Causes of the forest dying
Damage levels
Forest damage in Rhineland-Palatinate
Forest damage in Europe
Is the forest dying to be still stopped?
Introduction
By forest dying one understands, if wide damage in forest stocks is present, which lead to becoming extinct Nadel-und deciduous trees.
Already for approx. 250 years a fir dying periodically occurring by insufficient ecological conditions is observed. Already since that 19. Century are well-known forest damage by exhaust gases of industrial plants. This sucked. Smoke damage was limited however to close range of industrial plants. Due to the increase of the chimneys in and the 70's 60's, the pollutants do not arrive any longer in the direct proximity of the Emitten at the ground, but can hundreds of kilometers be transported before them are abgeregnet.
Causes of the forest dying
From where the damage comes is still investigated, which leads up to the death of the trees, and how different harming influences and effects are chained. As proven it is considered however that the immissions (air pollution) disturb the alive system tree surface-to-air lastingly. Most dangerous pollutant is the sulfur dioxide. It originates mainly from force and district heating plants and from the industry. At the secondarymost dangerous group of pollutants, which is nitrogen oxides, to more than 55% the motor vehicle exhaust gases taken part. Sulfur dioxide and nitrogen oxides will affect particularly by the connection with oxygen in air and water to strong sulfuric acid and nitric acid and only these acids as heavy poisons the plants. Under influence of sunlight additionally from the nitrogen oxides ozone, a strong plant poison forms. The acids, ozone and other sauerstoffverbindungen develop only if the primary pollutants sulfur dioxide and nitrogen oxides already are one while in air. It explains also that e.g. the forest is healthier in the industrial area, as in the Bavarian forest. Acids and ozone destroy the protecting layer of wax on needles and pages. They prevent also that the gap openings at the needles can close and regulate the water regime. Thus the tree evaporates in warm weather vitally necessary humidity. Acids and heavy metals at the same time attack also the soil. The Bodenversauerung damages the roots; the ill roots take up fewer waters. Metal salts in the soil are washed, poisonous metal connections to develop. They damage the soil organisms, which are indispensable for the food intake of the tree roots. The nutrients in the soil are reduced at the same time. The upper and underground of poisons thus enough food and water cannot take up attacked tree, evaporated however more than in the healthy status. A so weakened tree resists a particularly dry summer or a long with snow break and frost damages hardly still.
Also different, immission-conditioned harming factors, e.g. extreme Witterungs-und of climatic events, forest-structural errors, mushrooms, bacteria, viruses, harming insects, are consulted for clarifying the causes of the forest dying. It has itself however put out that these cannot be the primary causes, however as a causer of secondary damage to occur or the effect of the pollutants to strengthen be able.
Forestry differentiates between the following damage levels , after which the statistics of the Federal Republic of Germany are raised:
Harming level 0: Trees with fewer needles lost as 10% or damaged pages are considered still than healthy.
Schadstufe1: weakly damaged, ailing, between 10 and 20% of the needles or pages were lost. With coniferous trees bald places in master proximity, since old needle classes dropped. With deciduous trees weakly branches outside at the crown and vergilbtes leaves beblaetterte.
Harming level 2: medium strong damaged, ill, between 25 and 60% of the needles or pages are missing. With coniferous trees: Branches at the trunk bald, trunk well visibly, with firs close branches around the point spread (" stork nest "), with spruces hanging branches, vergilbte brownish needles. With deciduous trees: Early sloping, waved bent, partly braunraendrige pages, dry of branches and branch points.
Harming level 3/4: strong damage, seriously ill to died, more than 60% needle or page loss. With coniferous trees: Fir with " stork nest " and increasingly bald, spruce with died treetop, frequently with brown needles. With deciduous trees: Sections of the crown die.
Forest damage in Rhineland-Palatinate
After that newest forest damage report submitted by the government from Rhineland-Palatinate only 40 of 100 trees on harming level 0. the proportion of the clearly damaged trees (level 2-4) is increased in the comparison to the previous year 2 per cent points and amounts to now 24%, whereby the proportion of the weak-damaged trees (Stufe1) decreased/went back on 38 per cent. The proportion of the oaks with clear damage has this year with 54% a new highest level achieved after it 1993 with 27%, 1994 bei38% and 1995 were about 50%. The proportion almost remained the same clearly more damaged for Fichten(14%), Kiefern(7%) and beeches (35%).
Parallel to the observation of the forest ecological system (crown status, soil status,
Growth...) also measurements of the environmental condition (emission measurements become,
Deposition measurements, meteorological measurements) executed. These put
to light that since 1988 the sulfur dioxide concentration of air clearly back
laeufig is, itself however since beginning of the measurements the nitrogen dioxide concentrations
and also the ozone concentrations noticeably did not reduce. Altogether are appropriate the acid and nitrogen entries as well as the ozone concentrations over as ecological system compatible for regarded threshold values clearly.
Forest damage in Europe
According to the specification from " data to the environment 1990/91 " is white Russia with 54% that
Pollutant level 2-4 most strongly affected by the forest dying, followed of that
Czechoslovakia (46,6%), Great Britain (39 %), Poland (38,4%) and Lettland (36%)
scarcely before the new countries of the FRG (35,9%). It is remarkable that the new Lands of the Federal Republic
more than doubly as much proportion of forest damage of the levels 2 -4 register than those
old Lands of the Federal Republic with 15,9%. To few by the forest dying in Europe those are affected
Countries Austria (3,9%) and Spain (3,8%).
Is the forest dying to be still stopped?
- possible measure
Quotation from the forest damage report 1996: " For the protection of the forest soils before further Versauerung and nutrient depletion a location-referred modified limewashlimewashing limewashing is necessary and humuspflegliche forest management apart from a further emission reduction. "
In addition, by some scientists recommended limewashing of the forest soil to
Balancing of the Bodenversauerung is disputed. In an attempt, in which by way of one period of a surface limewashed by 6 years artificial acid rain was supplied, it turned out that the sickerwasser contained much higher nitrate contents (scarcely 200 mg per l) below the limewashed surface than under the ungekalkten surface (70 mg per litre). That applies also to heavy metals such as iron, lead and copper, which are mobilized by limewashing. From these results the scientists derive the urgent advice to deal with the so-called compensation limewashing carefully.
Since it seems almost impossible thus to recover the already available damage of the forest effectively we must try to work against the causes of the forest dying:
the air pollutants! Quotation dia.dia. dia. Martini: " Their reduction remains still therefore the most important forest preventive measure. "
Here I would like the demands, those the protective association German forest
(SDW) places regarding the reduction of the air pollutants, list:
- traffic avoidance is by town development measures, those the integration of living and operating and the organization of the spare time and the lebensbeduerfnisse foedern to grant highest priority.
- an increase of the oil tax around approx. 25 Pf. per year tied for the development of the public local passenger traffic, in particular in the surface.
- a legal regulation with the target that at the latest starting from the turn of the century
average fleet consumption for each motor vehicle at the most 5 l per 100 km/h amounts to.
- the intensified development of the rail-bound goods traffic network, in order to reduce the pollutant output of strongly expanding LKW traffic.
- a stretch-referred transnational heavy traffic delivery, which considers the strong environmental impacts of the road haulage apart from the way costs also.
- the European-wide abolishment of the tax exemption on kerosene as well as the introduction of the value added tax obligation for international flugtickets.
Additionally each particular of us has the possibility of reducing the pollutants:
Energy savers reduce by smaller consumption also the emissions, e.g. by technically perfect heating systems, economical household appliances, use of public means of transport, union to driving communities, voluntary speed limit and low-pollution auto this list are arbitrarily extendable and by conscious behavior can to everyone a small contribution for the reduction of the air pollutants make and thus also for the preservation of our forests, which serve so many of us regularly for the relaxation and recovery. Because that the forest is able to regenerate by the reduction of the air pollutants an attempt showed, with which only by pollutants released water on the forest soils was sprayed, whereupon the soil clearly fewer ammonium, nitrate, indicated sulfate and aluminum. Also the fine root recovered and increased by approximately 1/3 in mass, and the magnesium supply improved clearly. Efforts toward a reduction of the pollutant entries from air, then close the researchers of this project, were thus possibly already soon recompenced. then the results of the forest damage research show, would benefit that not only the forests, but also the water and of the *** TRANSLATION ENDS HERE *** Atmosphä re.
