0158-B1
Leonid Kondrashov 1
Formed under influence of specific nature conditions of the northern-east periphery of Asia, climate severity and contrast, complex mountain relief, permafrost availability as well as active volcanic processes, the vegetation, wildlife and soil cover of the Sea of Okhotsk surroundings (Priokhotie) are highly peculiar and have no counterparts in the world. Washing 10 ths km of Russia, the Sea of Okhotsk has a crucial impact on the environment of surrounding territories. In its turn, the vegetation of these areas have a special soil and fish protective significance, together with positive affect on conservation and productivity raise of many other types of biological resources.
Priokhotie is characterized by extremely unstable, hardly restorable, ecological systems and high burning ability of forests growing on cryosolic soils. The forests are a core of regional ecological balance. Even small disturbance of ecological balance here can lead to irreversible negative consequences. In connection with such factor as permafrost, the impact of disturbances on ecosystems is deeper, more complex and diverse than in the regions without permafrost. This can provoke not only evolutional but even revolutional changes, the elimination of which frequently due to different reasons could appear impossible. The spread of the Sea of Okhotsk influence on terrestrial ecosystems is determined by the mammoth object itself (1.5 million km2): the greater part of its waters washes the coast of Khabarovski Territory and Sakhalin, Kamchatka and Magadanskaya regions.
There are several proposals to arrange wide-spread study of this Sea and surrounding area including concrete directions of research work, since the impact of these ecosystems is felt even in many countries. The most important issues should imply a demonstration of sound results, methodology and research techniques.
Priokhotie natural conditions are considerably differ from that of southern part of the Far East and, together with this, they are very inhomogeneous in various parts of this vast area.
The main factors, determining the distribution of vegetation in Priokhotie are the following:
Severe climatic conditions in coastal and continental parts, greatly differing in precipitation regimes, air humidity, heat availability, etc (Chandler, 1991). The annual average precipitation in the continental part is twice lower than in coastal one and vegetation period is longer for two weeks. Dzhugdzhur range is the most severe zone with the moving snow caps and vast spread of valley ice. Freezing thaw intensity strongly fluctuates year to year. The availability of cryosolic soils influences the exposition of solifluctational processes and thermokarst. Mountainous-valley relief impacts the soil and hydrologic conditions, and significantly converts the action of climatic factors, determining the demonstration of mezo- and microclimatic peculiarities even in the restricted territory (Conservation..., 2000). Dzhugdzhur is a natural barrier for humid cool sea air masses. Traces of forest fires and other disturbances are encountered everywhere (pined burned stands, marks of fire on stems, dead stands, etc.)
The severity of nature greatly influences soil formation and biological turnover and determines the predominance of larch forests, wide spread occurrence of Pinus pumila and mountainous tundra.
The coastal forest protects extent areas from the influence of strong winds. Latitudinal zonening of vegetation is clearly exposed in all parts of the territory, though in many cases the vegetation and even habitat are strongly changed by fires (Ostroshenko V.V., 2000). In the continental part of the region, the vegetation is schematically presented by the following belts: 1. Larch and pine forests; 2. Ayanski spruce forests; 3) Betula Ermanii forests; 4) Pinus pumila overgrowth and 5) mountain tundras.
In the coastal part of the region, there are no pine forests; the share of Ayanski spruce and Betula Ermanii forests is larger. The alteration sequence of vegetation latitudinal belts sometimes is broken. For example, in vegetative stripes with severe wind regime, there are comparatively large areas of stone taluses and Pinus pumila overgrowth. On the coast, such habitats sometimes have specific elfin woodlands of larch, while on the ice fields; the composition of vegetation groups depends on the time of ice thawing. The valley areas, early freeing themselves from ice, are characterized by groups of Salix saxatilis with participation of bog bilberry, Kurile tea, Betula exilis and other species. On separate ice fields, Salix alaxensis is met in spots and stripes. Along active water ways, free from ice, there can be met Rheum compactum, Epilobium, Carex and some other species; Carex prevails on weakly drained areas. The ice formation on zones, occupied by wood vegetation, is accompanied by trees shrinking; the areas of dead stands also increase with the progressive increase of ice.
The Okhotski region's rate of forest coverage is 18-25% with the average rate for Magadanskaya region about 25% having fluctuations from 5% (Anadyr) to 30-38% in the south; Kamchatka's figure is - 25 to 35%. Behind these average levels there are completely or almost completely huge treeless areas located in middle and upper belt of mountains and hidden sharp fluctuations of rate of forest coverage in the separate watersheds (Artsybashev, 1998).
Quality of locality and stem wood growth estimations give the following picture of Priokhotie forests productivity. Larch forests in the north continental regions of V and Va classes of quality of locality take 80%, III-V classes - 16%, the rest (mainly III class) take about 2% of the area covered with larch stands; in the upper part of Kolyma river basin and Priokhotie regions of Magadanskaya region, the stands of V and Va classes take about 60%, IV class - about 30%, III and higher - about 10%, but stands of I-II classes are encountered very rare on small sites. Similar distribution is in larch stands of Okhotski region taking into account the fact that the share of V and VA classes is more than 70%.
In Kamchatka there are 13% of coniferous stands of V and VA classes of quality of locality. IV class takes more than 60%. Betula Ermanii forests by 75% consist of wood stands of V-Va classes and about 25% - IV class. In white birch stands more than 70% of the area is taken by the stands of IV class, about 20% - III class and higher and the rest part - V and lower classes.
Valley forests, mainly poplar and Chosenia arbutifolia, have higher productivity. Stands of III and higher classes of quality of locality take 30-35% (Kamchatka) to 60-70% (continental regions of their area). The rest part of these forests is presented by the stands of lower classes.
The decumbent forests of Pinus pumila and Alnus have average closeness in the limits of 0.3-0.4. Open woodlands with stands density 0.3 and lower are highly spread in the North and East having natural and fire origin. On continental part they are almost fully formed by larch but in Kamchatka - mainly by Betula Ermanii. The larger part of natural larch open wood lands are pre-tundra and sub-goletz forests. Betula Ermanii open wood lands of Kamchatka cover mountain slopes of various exposition and elevation. Open wood lands of fire origin extend very wide under various conditions and frequently resemble natural ones.
Priokhotie of Khabarovski Territory, for example, includes four forestry enterprises Okhotski, Ayanski, Chumikanski and Nikolaevski with the forested area more than 21 million ha and 1.9 billion cubic meters of timber volume. The predominant species is larch covering 88.2% of forested land. The share of pine is 5.7%, spruce - 6.1%. Region forests have diverse habitat conditions (I-Va classes of quality of locality) and in general not a high productivity (84-180 m3/ha). The share of mature trees is 61%, including 37% - overmature trees. Young growths take 14.3%, middle aged - 14.5%, ripening - 10.2% of forested land. General average growth of coniferous species in Priokhotie is 21.7 million m3.
Nature-climatic and forest pyrological peculiarities of Priokhotie are significantly different from south and central parts of Khabarovski Territory. In particular, in the south of Far East two peaks of burning seasons are predominant - in spring and autumn. But Priokhotie has the only peak of fires - in summer (June-July). Here, the droughty and fire risk periods happen together with strong west winds and high temperature but low humidity of air supported by lightning activities. Larch stands predominance in the forest fund as well as the great number of open wood lands, burned areas, ramped cuttings, dead standing trees and windfalls with grass cover predetermine a high natural forest fire danger. 25% of the territory has I-III classes of fire danger which means a higher forest fire risk. Hence, Priokhotie fire danger coefficient is 0.6-1.2, while for the majority of the Far East; it is in the range of 0.5-0.8. The period of fire risk, according long-term data, is 140-160 days (Sheshukov, 1992). It increases with moving from west to east. In Priokhotie running ground fires (18.2%) and stable litter-humus fires (76.4%) prevail. The share of crown and peat fires is not high, correspondingly 4.3 and 1.1%. This resembles the situation for the whole Far East, where, according to data for last 30 years, the tension of fire risk is characterized by the following way: I class of fire risk is 21% of days, 2 class - 16.3%, 3 class - 25%, 4 - 27% and 5 - 11% of days.
| Table 1 - Burning level of Priokhotie |
| Forestry enterprise | Number of forest fires, units | Total area of forest fires, ths ha | Average area of forest fire, ha | Direct wood losses, ths m3 |
Ayanski |
483 |
41.9 |
86.8 |
498.6 |
Okhotski |
416 |
24.2 |
58.3 |
235.9 |
Region total |
1366 |
123.4 |
90.0 |
1154.6 |
Fire dynamics for last 30 years shows that extremely dangerous seasons became more frequent. In 1952-1974 there was only one extreme summer season, while in 1974-1999 such situations occurred 7 times. The shortage of financial and technical means promote the increase of large fire area (more than 100 ha) from 9 to 17%.
Usually postfire regeneration occurs in 2-7 years. But with incoincidence of fires and seed years (reiteration of seed production averagely 5-7 years) as well as with strong ramping of soils in the first 2-5 years after fire, such areas are left unforested and convert into unregenerated burned-out forests (barrens). Burned areas regrow with grassy-bushy vegetation and accumulate undecomposed forest litter interfering with seeds development. On steep slopes after intensive fires, the soils are washed out forming stony areas without any vegetation. In lowered areas as a result of soil temperature raise by 6-11 degrees there observed thawing of permafrost to the depth up to 1.5 m, which leads to their bogging. From total number of investigated burned areas there was no regeneration of main species in 36% of them, 21% were ramped, and 6% converted into stony areas, 9% was bogged. However, burned areas are characterized by powerful growth of small reed and firetop.
Through Priokhotie study, two points became evident. There is a limited understanding of the range and extent of climate change impact in Priokhotie and, as such, there must be a considerable work to refine that understanding and to develop workable adaptation approaches.
Thus, the research work objectives could include the following:
(i) produce a synthesis of our understanding of causes and consequences as well as driving forces of Atmosphere-Ocean-Cryosphere interaction in the Sea of Okhotsk and surrounding environment;
(ii) determine research priorities of environment change and investigate the role land cover and sea as a sink or source of CO2;
(iii) develop a typology database comprising physical, ecological and socio-economic parameters for the Priokhotie zones.
The most important thing is to determine how integrated hydrological, atmospheric, chemical, biogeochemical and ecological components will evolve under rapidly changing conditions of environment, what they reveal under close interaction.
The scope of the investigations could include the following works:
Due to its potential, Prokhotie shall undoubtedly provide for revealing the interaction with global processes, and vice versa. A potent global-regional mutual infusion and effect on such a scale would probably produce new results, thus defining the future directions for a stable development and conditions of the environment, especially in a case of a long-term formation of processes.
Some innovational characteristics can be represented by the following:
The results obtained should be commensurable, provide for their consideration in the aggregate, and yield the data for comparison and gaining of prospective results.
Forest vegetation distribution in Priokhotie is very uneven. Behind general mammoth sizes of forested areas and wood stocks is hidden a shortage of commercial wood, unforested areas.
Severe climatic conditions, mountainous character of the relief, long seasonal freezing, and fires influence the growth peculiarities, composition, and quality structure of wood stands. Region boreal forests implement important ecological functions in forming planet climate (cleaning of air and waters, protection of waters and soils, conservation of wildlife, CO2 sequestration). Violation of the environment balance can give a push to irreversible ecological consequences: change of river water regime, raise of cryosolic soils thawing, increase of fires, change of species, biodiversity decrease, etc.
The environmental, economic and social costs associated with the impacts and adaptation of current climate in Priokhotie is large and projected changes in climate are expected to increase those costs. As Priokhotie situation is strongly linked to that of its natural ecosystems and water resources, the responses of these to projected climate change will be critical in determining the environmental, economic and social costs and benefits of climate change for Priokhotie. The location, structure and functioning of terrestrial and aquatic ecosystems would be altered as a result of expected changes in relative season length, species distribution, population, habitat and competition between species. Their capacity to adapt would be tested by fast, possibly irregular rate of warming.
The first and main principle of approach to determine the ways of Priokhotie forests use must be admitting their sharply raised protective functions and need to establish raised standards of rate of forest coverage.
To create a rational and sufficiently differentiated system of forests use and reforestation, it is necessary to implement large research and experimental work, since modern information about these forests is completely insufficient to solve many problems.
Northern forests of the Far East extend from Uda river basin (Khabarovski Territory) to Kamchatka and Magadanskaya regions. Practically, there is no valid information about forest resources in the north of Khabarovski Territory: Okhotski, Tuguro-Chumikanski and Ayano-Maiski administrative regions and some othrs. Fragmented investigations of descriptive character do not give a full idea about qualitative and quantitative parameters of the forest fund on the area more than 19 million ha. There is also no concept of these forests management.
Long insufficiently regulated forest use of coniferous species in the long run led to decrease of forests productivity. The main reason for such dynamics, according Vyvodtsev, is intensive commercial cuttings and fires. Such tendency was registered in European part of Russia, where decrease of productivity and growth, change of coniferous species for deciduous, regeneration of areas with genetically weak self-seed after concentrated clear cutting were registered (Vyvodtsev,1996).
With anthropogenic influence on forests increase there appeared stable tendencies for protective functions increase, e.g.; rate of forest coverage decrease by 8.2% will bring up the decrease of annual ground waters flow by 19-20 mm, but areas where coniferous species were changed for deciduous would decrease the period of forests intensive impact cycle on carbon dioxide assimilation.
Significant influence on forests and on general productivity of habitat is made by forest fires. Past fires led to the change and disturbance of greater part of North-East forests and converted millions of hectares into stony areas, bogs on which natural regeneration practically ceased, and artificial - extremely difficult and possible only on small areas. Fires in many cases decreased the upper border of forests and evidently moved to the south the north limit of forests distribution.
There is no doubt that the terrestrial ecosystems of Priokhotie play a very important role, as well as no doubt that this role will likely change over the coming decades as a result of global environmental change. But there is still much uncertainty over and debate about the magnitude and direction that these changes could take. There is a great need to arrange international efforts to investigate this significant even for world ecological problems region (Bakka, Sobolev,1998).
1. Artsybashev, E. S., 1998. Forest Fires Fighting, Sankt-Peterburg, 178 p.
2. Bakka, A.I., Sobolev, N.A., 1998. Prerequisites and Prospects of Northern Eurasia Ecological Network Formation, Nizhniy Novgorod, 82 p.
3. Chandler, C., Cheney, Ph., Thomas, Ph., Trabaud, L., Williams, D. Fire in Forestry. 1991.Krieger Publishing Company, Malabar, Florida, 748 p.
4. Conservation of Biodiversity of Kamchatka and Coastal Waters, 2000. Petropavlovsk-Kamchatski, 156 p.
5. Ostroshenko, V.V., Forest Fires in Priokhotie, 2000. Khabarovsk, 109 p.
6. Sheshukov, M.A., Savchenko, A.P., Peshkov, V.V.,1992. Forest Fires in the North of the Far east. Khabarovsk, 95 p.
7. N.V.Vyvodtsev. Normative basics for forestry in the north of Khabarovski Territory (conceptual aspect). Khabarovsk. 1996.
1 P.O.Box 4/5, Khabarovsk-Centre, 680 000, Russia, tel/fax:7(4212)294983
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