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Progress of gene conservation of Norway spruce (Picea abies Karst.) in Russia Andrey Prokazin, Elena
Mochalova, Iliodor Routkowsky and Ivan Popivshchy Introduction Norway spruce (Picea abies (L.) Karst.) is one of the main forest species in the European part of Russia and there are hundreds of studies on its diversity. In the previous report (Routkovsky et al. 1997) very general data were given about the state of activities on Norway spruce genetic resources conservation in Russia. This paper aims to provide a more detailed analysis of the species' intraspecific diversity and activities for its conservation. Natural conditions in the distribution range As it can be seen in Fig. 1, Norway spruce extends in the forests of the European part of the country, from Karelia to the north (north taiga) to the forest and steppe regions of the south, and from the western boundaries of the country (coniferous-broadleaved forests) to the taiga forests of the Urals in the east. Thus, all forestry regions of European part of Russia are represented in the species' range. The corresponding climatic conditions of distribution regions of Norway spruce are extremely varied. For example, climatic data characterizing the climate of north (Karelia), central (Vologda province) and south (Bryansk province) parts of the species range may be given for such traits as averagelength of vegetation, mean annual temperature and the quantity of precipitation in a year. For Karelia they amount respectively (on average) to 130 days, +1° C, 440 mm; for Vologda province, 159 days, +2.3° C, 580 mm; for Bryansk province, 185 days, +4.7° C, 580 mm. (The forest seeds regionalization 1982). No less different are the soil conditions of regions of growth of Norway spruce forests (The forest encyclopaedia 1985). To the north of the range this is the combination of podzol ferrugineous humus with mire-podzol soils (Karelia) and also combinations of mire-podzol, peat-mire and gley-podzol soils (Arkhangelsk province and Komi Republic). The central part of the range (south of 64° north latitude and north of 55° north latitude) is occupied by podzol and turf-podzol soils in combination with marshy and marshy-podzol soils. Further to the south (from Tula province in the west to the Bashkortostan Republic in the east) - grey forest soils are changed by different types of chernozyom in the far southern parts of the range. Some geographical peculiarities of the stands The above mentioned diversity of climatic and soil conditions had to be reflected on diversity of spruce forest types and their composition. For example, in the spruce groves of Karelia that are swamped for 50-70 % of the time, the number of bilberry spruce forest type is 56-59%, the bog-moss types is 14-15% and red bilberry forest to 5-9%. Farther to the south lies a great portion of green-moss and bog-moss forest types (south of Arkhangelsk, Vologda, Kostroma, Kirov, Bryansk, Leningrad, Novgorod, Pskov provinces) and also oxalis and bilberry spruce forests (Moscow and Tver provinces).
Fig. 1. Picea abies (L.) Karst. (1, 3), Picea obovata Ledeb.(2, 3) and Picea fennica (Regel.) Kom. (3) ranges. Depending on forest growth conditions, the composition of the forest stands changes. Pure spruce stands and also stands with the a mixture of birch, aspen and pine are characteristic of the taiga forests in the northern and eastern parts of the range. Further to the south in the mixed forest zone, oak, lime, and aspen are included in the spruce forests structure. From the south to the north the site quality of spruce stands is decreasing (The atlas of USSR forests, Fig.2). So, in the north of Karelia the average site quality of spruce forests is IV.6, in the south of Karelia - III.9, in Kostroma province - II.5, in Yaroslavl province - II.0, in Tula province - I.2. To a large degree low productivity of north and middle taiga forests is dependent on early frosts, which may be observed here in any month of vegetation, and also on the soil temperature in the rhizosphere. According to N. Kazimirov, 1983, the maximum value of this characteristic in the plain regions of the European part of Russia reaches 15-16 ° C but in the regions of north taiga it only reaches 5-6 ° C in June, which is insufficient for root growth. Respectively, in the north taiga the main root mass is concentrated at a depth of 20-30 cm, in the regions of middle taiga at a depth of 30-40 cm, and in the zone of coniferous-broadleaved forests at a depth of 40-50 cm. The shallow root system of Norway spruce on the north is the main cause of wind throws. In light of this, average volume of Norway spruce stands lowers naturally from the north to the south and from the west to the east, m3/ha (The forest fund of Russia 1995): North region - 114.2; Northwest region - 154.3; Central region - 179.1; Volgo-Vyatsky region - 135.9; Central-Chernozyom region - 195.3; Povolzhsky region - 178.9; Ural region - 151.2. With that the volume of mature stands, measured by their high density, may be more than nearly twice as large as the average characteristics mentioned. So, according to Lositsky and Chuenkov 1980, in Ivanovo province (Central region) 80 aged stands have occurred with a volume of 528 m3/ha. In Karelia and Arkhangelsk provinces (North region) in the mature spruce stands the volume may reach 450-550 m3/ha. The fruit bearing periodicity of Norway spruce decreases from the north to the south: 5-10 years in Karelia and Arkhangelsk province, 3-7 years in Vologda, Kostroma, Kirov and Perm provinces, 2-4 years in other regions of the range of the European part of Russia (The forest seeds regionalization 1982). With this, the average value of fruit bearing abundance in the natural stands of Norway spruce do not fluctuate much in different administrative regions (Provinces and Republics) which are included in its range - from 0.9 to 1.4 (to a maximum of 5.0). The study of genetic diversity by means of traditional methods The most important publication devoted to the problems of Picea abies diversity in Russia is the work of L. Pravdin "Norway spruce and Siberian spruce in the USSR" 1975. He defined 4 main factors which have caused the modern intraspecific differentiation of Picea abies: disjunctivity of its range into small islands (refugia) for long time geologic periods during the ice age; the natural selection of genotypes in the changing environment; the introgressive hybridization by the meeting of primary isolated populations during their migration from refugia; continuing mutagenic process. He noted the high probability of spruce refugia dating back to the mounting conditions: the East Carpathians, the foot of the south and east Alps, the Western Forural (east of the Kostroma city), the Scandinavian peninsula western sea coast. According to L. Pravdin, in the Pleistocene Siberian spruce ( Picea obovata L.) dominated the Russian plain all the way to Moscow, and then was replaced by Norway spruce. According to K. Rubner 1960, the Russian part of the Norway spruce range belongs to one of three isolated parts, the north Baltic (Nordisch-Baltisches Gebiet). The original investigations of L. Pravdin, based on the analysis of 324 samples of cones, seeds and leaves from 324 points of the European part of the former USSR (size of cones, the shape of seed scales, the length of the seeds and the leaves were measured), allowed him to come to the conclusion that, on this territory, practically everywhere there are spontaneous hybrids from introgressive hybridization of Norway spruce with Siberian spruce. This could explain why hybrid forms with the expressed traits of Siberian spruce are common to the Ural region. In the literature hybrids, described as Picea fennica (Regel) Kom. - the Finnish spruce, are mentioned. L. Pravdin 1975 has reviewed the available literature data about the participation of different species and hybrid forms of Norway and Siberian spruce in the spruce stands on the territory of the former USSR, using the forest zones and subzones distribution according to V. Sochava, 1956 (Fig.3). Below is a short summary of some basic thesis of this work. According to M. Shcherbakova (1973), in the north taiga subzone - in Murmansk province and in the Republic of Karelia, north of 64° of north latitude - spruce is represented mostly by hybrid forms and by Siberian spruce. South of the above mentioned latitude the representation of Norway spruce and its related hybrids with the Siberian spruce is increasing. According to L. Pravdin,on the whole, the north taiga forests are represented mostly by Picea fennica (Regel) Kom. In the middle taiga subzone - from the west to the east Norway spruce is gradually being replaced by Siberian spruce, as shown in the works of V. Panin (1959, 1960a, b, c, 1962) applied to the Vologda province. Hybrids related to Siberian spruce, are mostly found in the worst conditions of growth. In the south taiga subzone - the same tendency is apparent. Based on the study of cone morphology and seed scales structure, M. Shcherbakova 1973 concludes that, in the spruce stands of the southern taiga Norway spruce and Finnish spruce are exclusively representedand Siberian spruce are absent. According to A. Karpenko (1968,1972) and D. Danilov (1943), Norway spruce occupies about 12 %, Siberian spruce approximately only 1 %, Norway spruce related forms 68 % and Siberian spruce related forms 15 % of the spruce stands of the Udmurtia Republic and Kirov province. Siberian spruce, related forms and hybrids are the most represented on the east and southeast of the studied region. According to P. Popov 1971, in the southern taiga forests of Perm province the clearest border between the ranges of Norway and Siberian spruces can be seen. The wide zone of the introgressive hybrids of these species is there. In the zone of broadleaved-spruce forests (to the south of taiga zone) according to some authors, Norway spruce and its related hybrids with the Siberian spruce are mostly present. In particular, L. Milutin 1963, judging by the seed scale forms of spruce in Bryansk province, came to the conclusion that the absence in Siberian spruce stands was due to the high representation of Norway spruce and its hybrid forms. In fact, the author noted that by the end of the X1X century Siberian spruce near Bryansk city totaled only 5% of the total number of spruce trees. The same author hypothesized that the disappearance of Siberian spruce in this region is connected with the droughty period from 1938-1939, when the majority of the Siberian spruce confined to the lowlands died out. Phenotypical diversity From the north to the south, the length of cones, the mass of seeds and their germinability increases. If in the north of the range (in the northern taiga subzone) the middle cones length amounts to 6.1 cm, in the south (in the coniferous-broadleaved forests zone), it amounts to 9.8 cm. The mass of 1000 seeds amounts respectively to 3.2 g in the North and 5.3 g in the South, their germinality reaches 32 % and 69 % respectively (M. Shcherbakova 1975, G. Tishkevich 1962). According to M. Shcherbakova 1973, a considerable variation of the cone length and the seed scale numbers of Picea abies in the European part of the Russia have been noted. A great number of Russian scientists investigated the discoloration of the female strobila of Norway spruce (Albensky 1930, Kharitonov 1937, Voychal 1955, Pchelin 1957, Yurkevich 1958, Chernyavsky a.o. 1959, Panin 1960a, b, c, Moskvitin 1962, Milutin 1963, Bakshayeva 1966, Nekrasov 1966, Mamaev 1973, Shcherbakova 1973, Kazimirov 1983). The presence of forms with red, green and pink cones in the same population were noted and attention was paid to the extremely complicated diversity pattern of the phenotypic characteristic dependent on the ecological conditions. The same authors isolated the phenological forms of Norway spruce with a mean difference of 10 days in end of the dormancy period. There is information on the variability of Norway spruce for shoot fluffiness (Lindquist 1948, Pravdin 1975, Bakshayeva 1962) and extensive data about the variability of spruce crown forms and branching types in the former USSR (Sukachov 1928, Yurre 1939, Molchanov 1947, 1950, 1967, Voychal 1955, Shishkov 1956, 1957, Vilikainen 1957, Albensky 1959, Bakshayeva 1959, 1966, Lange 1960, Milutin 1963, Zaykov 1965, 1968, Shcherbakova 1973, Kazimirov 1983): columnar, widecrown, snakear, twigar, bristlear, combar, flat, a.o. The considerable differences in the colour (reddish and grey) and structure (smooth, rough, pity, curly, cracky, a.o.) of the Norway spruce bark surface were also noted (Fyodorov a.o. 1962). It is necessary to mention that various authors have introduced their own names of the spruce bark surface structure, for example, smooth-crusty and scale-crusty (Yurkevich, 1970). So, in spite of the abundance of publications (Sukachov 1928, Kapper 1954; Moskvitin 1957, 1959, 1962, Yurkevich 1958, Albensky 1959, Golod 1960, 1961; Grozdov 1960, Rostovtsev 1962, Milutin 1963, Ronis 1966, Yurkevich, Golod, Parfyonov 1970, Kazimirov 1983) currently there is no generally accepted classification of the Norway spruce forms for this character or for the crown form either.
Investigation of spruce ecotypes in provenance trials The most important stage of spruce gene pool investigation in the former USSR was the early 1970s. Work began in 1973 with a large-scale experiment for the establishment of the provenance trials network of the main forest-forming species (spruce, pine, larch, oak, fir and Pinus sibirica - "cedar sibirica"). The scope of the experiment is characterized by such items as the number of seed harvest points and the number of provenance trials creation points. For spruce these numbers are 60 and 21, for pine - 126 and 50, for larch - 47 and 21, for oak - 47 and 21, for fir - 23 and 8 and for "cedar sibirica" - 29 and 8 respectively. The stations for spruce seed harvesting are given in Table 1, and the points of provenance trials creation are shown in Fig. 4. The value of the experiment is defined not only by the great number of tested ecotypes and wide network creation points, which cover the ranges of the above mentioned species, but by the unique well-developed methodology of the work (E. Prokazin 1972)). The main hypotheses of the method were the following: the seeds were harvested in the mature natural stands with an area at least from 2 to 3 ha, the most common forest types, normal tree breeding category, distant from the unknown artificial stands, in the stands not passed by several management measures (prethinning timber stands). For the provenance trials, the most favourable clearcutting forest areas for the growth of the respective species and typical for the region of creation were designated?. The provenance trials were created by rectangular blocks of the areas from 0.1 to 0.25 ha according to randomized ecotypes distribution in 3 repetitions. At least 10 years after the provenance trials began, it was foreseen to begin the selection of the best ecotypes for the complex of economically valuable characters and to begin the more detailed study of them. It was planned to test the best ecotype populations from the different forest types by means of creation of a new network/round of provenance trials (testing artificial stands of the best ecotypes) in the different natural conditions.
Table 1. The points of the Picea abies and Picea obovata seed harvest for the provenance trials network creation in the former USSR
11 - 15 - Belarus, 16 - 18 - Ukraine, 54 - 58 - Kazakstan. This ambitious workplan was not completely fulfilled. The created network of the provenance trials provided the possibility to develop (what?) fairly relevant to the forest seeds regionalization of the above mentioned species. At the same time, it was not possible to begin the second stage, i.e.the testing of artificial stands of the best ecotypes. The prepared programme of such activities for all the investigated species has not been realized because of the division of the former USSR and the rapid decline in the possibilities of centralizated funding and coordination. However, the previously created network is not only the monument of the scientists who participated in this experiment, but is also an instrument to gain further knowledge on ecotype’s vitality after their transfer in new ecological conditions.
Fig. 4. Economical regions: 1 - North, 2 - North-West, 3 - Central, 4 - Volgo-Vyatsky, 5 - Ural, 6 - Central-Chernozyom, 7 - Povolzhsky, 8 - North-Caucasus.
The most obvious results of the spruce provenance trials, besides the development of the forest seeds regionalization were the detection/pinpointing of the zone of the optimum growth of Norway spruce i.e. the Republic of Belarus and the new Baltic countries. Even before the provenance trials were created, the author and coordinator of the experiment, E. Prokazin, noted that the spruce seeds from Belarus provided for stands establishment in Sweden were 1.5 times more productive than the native ones and were frost resistant. According to the results of the provenance trials the data showed that some Belarussian and Baltic ecotypes surpassed the native ones in productivity, in Moscow province too. Moreover, data about the better fruit bearing of the north spruce ecotypes by the transfer to the south emerged. The theoretical supposition about the advantage of creating spruce seed orchards to the south of the reproduction sites of the mother stands was confirmed with the establishment of artificial stands using seeds from these orchards in intermediate stations i.e. between the point where the seed orchards were created and the area where the plus-trees were located. In some regions the most valuable ecotypes for productivity and stability in the provenance trials were seen as the base populations and form the basis for the further selection of even more outstanding forms in their seed and vegetative progenies. Investigation of genotypic diversity by means of modern methods Firstly it should be underlined that known circumstances in the 1930s in the former USSR had an extremely negative influence on the development of genetic explorations. Genetics as a science, and forest genetics in particular, were developing much slower than in the most developed Western countries. In fact, the high level of genetic investigation of forest species by methods of electrophoretic isoenzyme analysis was provided by two scientific organizations only, The Institute of General Genetics (IOGen) of the Russian Academy of Sciences in Moscow (scientific leader, U. Altuhov), and the Forestry Scientific Research Institute of the Republic of Belarus - BelNIILH (scientific leader - G. Goncharenko). With the division of the former USSR, plans that existed for organization of large scale genetic research on the main forest-forming species, under the scientific leadership of BelNIILH, through the organization of a network of genetic laboratories including all the forest scientific institutions of the Russia, were lost. Nowadays, far from the scientific problems, the heads of some of the provinces' forestry departments are beginning to recognize the necessity for the above mentioned genetic trials, in order to provide genetic control of the work carried out in the field of tree breeding and seed improvement, while selecting valuable forms for multiplication. However, even in relatively favourable regions the forestry departments are unable to find funds for the organization of such trials. It is impossible to find a solution to this problem on the federal level too. The problem is further complicated by the marked lack of highly qualified specialists in this field. The authors summarize below some results of Norway spruce genetic diversity exploration in Russia, carried out by a group of genetic laboratory specialists led by G. Goncharenko (G. Goncharenko a.o. 1989, V. Potenko a.o. 1993). So, in the Karelia forests, 25 genomes in 7 natural populations were found. of which? more than 60 % of gene loci were polymorphic and every tree was heterozygous for 19 % of genes. The average number of alleles for one locus was 1.95, and the effective number of alleles was 1.34, with 2.2 % excess of heterozygots compared to expected ones, according to Hardy-Weinberg. More than 27 % of diversity was related to the intrapopulation, and 2.5 % only to the interpopulation. It is interesting to compare this data with the results of similar trials conducted in Germany (Hertel, Ewald 1992) with the aim of recovering the native provenances with the help of clones. On the clonal seed orchards in Darmsdorf 36 clones were selected with a high level of expected heterozygosity in the progenies due to a high proportion of rare alleles in the parents. There the middle heterozygosity for 21 gene-ferment loci amounted to 0.22 with an average of 2.48 alleles per locus. Norway spruce is characterized by the following traits of genetic diversity. Polymorphism (P) (the proportion of polymorphic loci): P95 = 0.58; P99 = 0.79, that is somewhat lower than polymorphism than Picea obovata (P95 = 0.67; P99 = 0.83). Mean heterozygosity (H), Ho (H observed) = 0.203, He (H expected) = 0.207. The number of alleles per locus (A) = 2.58 the number of not rare alleles per locus (A1 %) = 2.52. Effective number of alleles (Ne) = 1.32. Comparing the above mentioned data for the whole range with the data received for Karelia, one can say that the Karelian spruce populations are characterized by the less polymorphism (P99 = 0.634), a much lower level of Ho (0.193) and He (0.181) polymorphism, less alleles per locus (A = 1.954), and no rare alleles per locus (A1 % = 1.341). It is also of interest to compare genetic diversity in natural and artificial populations of Norway spruce, because the level of diversity is one of the main characteristics defining the state of populations. The same authors showed, that in the artificial populations (seed orchards) of the species, the genetic diversity appears to be higher than in the natural populations, as with Pinus strobus in North America. It is obvious that this last finding is of importance for use in the work being carried out on the Norway spruce genepool conservation ex situ. Anthropogenic and technogenic influences The spruce forests of Russia, as in Europe on the whole, experience powerful negative antrophogenic and technogenic impacts near cities spreading over dozens of km. The most damaging of all is SO2, abundantly widespread due to the combustion of brown coal at thermal power stations (Cherny 1985). Besides that, mining of useful fossils, t some spots of water and wind erosion, areas with temporary flooding from toxic water, areas where the wastewater from refineries is dumped/stagnates, logged territories, plots with higher surface and ground water mineralization, etc. (Motorina, Izhevskaya 1980). Significant worsening of site conditions has been observed over the years with prevailing north- and north-east wind directions (Lovelius, Lairand, Yacenko-Khmelevsky 1985). In the late 1970s, for the first time around industrial enterprises in the north taiga, 4 zones of disturbed ecosystems were discovered. In 1986, the widening of all the areas of spruce stand degradation from 1-3% yearly was distinguished, and where traces of technogenic impact were not observed, it was necessary to distinguish an additional zone 5, where epiphyte lichens were beginning to die. On the Kolsky Peninsula, during the summer season more than 2000 kg of S and more than a 100 kg of heavy metals fall per km2 of spruce taiga. In the zone of complete destruction of the spruce ecosystems in organogenic (0-10 cm) soil horizon, metal concentrations at a distance of 5 km from the "Severonikel" enterprise (Monchegorsk town), are 30-40 times higher than elsewhere. In the second zone, dying trees prevail in the stands, and the leaf longevity amounts to 2-4 years versus 11-13 years under normal conditions. In the third zone, the leaf longevity amounts to 4-5 years and in the fourth zone, though the visible symptoms of damage are absent, the leaf longevity is, however, lower than the normal 6-7 years (Syroid 1988). The maximum level of pollution was in measured in 1989. Nowadays the enterprises' emissions are sufficiently reduced, but the model forecasts that even if enterprise activity is completely stopped, the spruce stands' degradation and the widening of the area of degradation will continue for some years to come, and only after that will slow recovery begin. At present the degraded areas of of spruce stands are total nearly 90 km (Tarko, Bykadorov, Kruchkov 1995). Technogenic transformation of the volume and the structure of soil cover phytomass of the spruce forest also occurs. So, in the northern part of the Kolsky Peninsula the soil cover phytomass volume in the spruce stands of the background zone reaches 1.7 kg/m2 (0.9 - 1.8 kg). In the buffer zone, where the initial stages of the spruce biocenose destruction occurs, the soil cover phytomass volume is reduced to 0.8 kg/m2 (0.2 - 1.1 kg). It is also reducing the species diversity for many of the green mosses and lichens. But in the zone of the technogene heathland, where spruce dies, the soil cover phytomass falls sharply to 0.1 kg/m2 (Lukina, Nikonov 1988). The negative influence on the spruce forests of the European part of Russia also have recreation functions are also caused by recreation activities. Territories used for recreation, experience a disturbance of the forest floor, the redistribution of its fractions and a strengthening of the destruction process. The reduction of the forest floor volume and its negative redistribution increase with the increase of slope steepness (Marphenina, Goncharova, Rozina 1988). The negative impact on the spruce stands may come to light under the influence of the surface flow of mineral fertilizers from arable land. This is particularly the case with regard to the natural recovery of spruce and the understory in the spruce-oxalis forests. Therefore, in Moscow province, in the middle-density spruce-oxalis forests essential changes in the age structure of secondary stands have been observed, as a consequence of the surface flow of mineral fertilizers form agricultural fields. The abundant grass cover in the zones of flow inhibits the spruce seedlings. Under the influence of N there are increases in interspecific competition, changes in the cenosis structure, and the portion and quantity of some species (Romanko 1980). Common forestry activities may also essentially disturb the spruce stands. The territories damaged by fire are colonized by pine forests, and the spruce seedlings become inhibited or are absent - the pyrogenic succession of the ground cover takes place. The greatest disturbances to the soil cover and the upper soil horizons (up to 90 %) are caused by mechanized timber cuttings in the snowless period of year. The main tracts, the spots of floor strippings and the places of woody waste burning amount on average 50 % of the clearcut area. The rest of the territory of the clearcut happens to be occupied by the slightly disturbed communities (Tishkov 1979). The new danger for the spruce occurred with the shift of the Russian economy to the market system. Foreign firms receive licenses to clearcut the spruce taiga in Karelia, Arkhangelsk province and carry out forest cuttings without considering the forestry requirements. The existing administrative system in the provinces is powerless against the prevailing market forces. The laws governing nature protection and forest genetic resources conservation are not working. Nature protection is more dependent on the good will of enterprises rather than on the the implementation of the law and on society's demands. This problem regards not only Norway spruce but on the whole envelops the largest biome in the World. All this requires coordinated actions for the future (Majewski, Angelstam 1995). The dynamics of changes in spruce forest areas In light of what has been mentioned above, some interesting data has emerged regarding changes in the spruce forest areas in the European part of Russia during the 20th century, when they were most intensively exploited. However, the authors were unable to provide any evidence to prove this. It was a success to find the data of the forest fund inventory for 1952, 1966, 1973, 1983, 1988 (The dynamics of forests 1989) and 1993 (The forest fund of Russia 1995) only, without a division of Picea abies and Picea obovata (Table 2).
Table 2. Changes in spruce forest areas for the main forest regions of the European part of Russia from 1952 to 1993 (thousands ha)
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