Pavel V. Krestov

Forest Vegetation of Easternmost Russia (Russian Far East)

The forest vegetation of the Russian Far East, an area of more than 3 million square kilometers in northeastern Asia, has been well studied by Russians but has remained unknown to most vegetation scientists outside Russia. The region is important because it represents natural vegetation processes and their environmental relationships over a huge territory, from polar deserts to cool-temperate forests, from the Pacific coast to the continental interior. These landscapes are among the best preserved forest ecosystems in the world. This chapter includes the first overview in English of eastern Siberian forest vegetation in its basic types, with a focus on phytogeography, ecosystem structure and dynamics, and developmental trends. Special attention is paid to the zonal forest types, including mixed broadleaf-Pinus koraiensis forests, dark-conifer (evergreen) forests of Picea ajanensis, deciduous light-conifer forests of Larix dahurica, broad-leaved deciduous forests of Betula ermanii, and the unique dwarf forests of Pinus pumila and Alnus fruticosa.

Succession following the catastrophic eruption of Ksudach volcano (Kamchatka, 1907)

Ksudach Volcano, southern Kamchatka Peninsula, erupted in 1907 and impacted over 2000 km2 of forests with air-fall pumice deposits. We identified three impact zones. In Zone I, deposits deeper than 100 cm destroyed all vegetation. Two early successional stages occur, a lichen-dominated desert and isolated patches of a pioneer herb stage. Zone II is defined by pumice deposits 30 to 100 cm deep. Deposits of 70 to 100 cm destroyed all vegetation, but left scattered snags. Here primary succession dominates recovery, but its rate varies. Isolated trees survived in deposits of 30 to 70 cm and primary and secondary successional stages form a complex mosaic termed an intermediate succession. In Zone II, the primary stages found in Zone I are joined by a dwarf shrub-herb stage and a secondary birch forest stage. Zone III occurs where thinner deposits permitted some vegetation to survive in all locations. Secondary succession dominates in deposits of 10 to 30 cm. Trees suffered damage, but survived deposits of 20 to 30 cm, while other vegetation layers were eliminated. Deposits of 10 to 20 cm eliminated mosses and lichens and but only reduced the number of dwarf shrubs and herbs. Deposits of less than 10 cm damaged herb, moss and lichen layers but did not eliminate any species. All sampled vegetation remains in a pre-climax state, having yet to recover fully from earlier eruptions. Reconstructed vegetation maps for before 1907 and for ca. 1925 are compared to the map of vegetation in 1994. Based on degree of soil formation, vegetation recovery and colonization rates at different pumice depths, and the current vegetation, we estimate that full recovery of the soil-vegetation system will take more than 2000 years.

Understorey vegetation in boreal Picea mariana and Populus tremuloides stands in British Columbia

Abstract We compared the species composition and species density of vascular plants in the understorey vegetation of boreal forest between Picea mariana (Black spruce) and Populus tremuloides (Trembling aspen) stands in British Columbia, Canada, and related differences in species composition and species density between the two forest types to dominant canopy tree species as well as a wide variety of environmental factors. We analysed 231 stands, distributed in three different climatic regions representing drier, wetter, and milder variations of montane boreal climate. Of these stands 118 were dominated by P. mariana and 113 by P. tremuloides. P. tremuloides stands had higher species density than P. mariana stands in all climatic regions, but species density of each dominance type varied among climatic regions. The floristic composition of the understorey vegetation was markedly different for P. mariana and P. tremuloides dominated stands. A detailed study on the effect of canopy dominance and local environmental factors on the understorey vegetation of the boreal forest was conducted using 88 stands from one of the three climatic regions. Using a combination of ordination and variation partitioning by constrained ordination we demonstrated a small but unique effect of canopy dominance type on the understorey vegetation, while a larger amount of compositional variation was shared with other factors. Our results accord with a scenario in which differences in primary environmental factors and humus form properties, the latter accentuated by the canopy dominants themselves, are the most important causes of higher species density in P. tremuloides stands than in P. mariana stands, as well as differences in species composition among the two canopy dominance types. Processes and time scales involved in the small but significant direct and indirect effects of the canopy dominant on understorey species composition are discussed. Nomenclature: Qian & Klinka (1998). Abbreviations: DMB = Drier montane boreal; MMB = Mild montane boreal; WMB = Wetter montane boreal.

Disturbance history and tree establishment in old‐growth Pinus koraiensis‐hardwood forests in the Russian Far East

. Dendro-ecological studies were undertaken to document the disturbance history in two old-growth mixed Pinus koraiensis-hardwood forests in the southern part of the Sikhote-Alin mountains in the Russian Far East. Establishment of four common canopy conifers, Abies holophylla, A. nephrolepis, P. koraiensis and Picea ajanensis, and three common canopy hardwoods, Acer mono, Betula costata and Tilia amurensis, were also inferred from population age structures and spatial dispersion patterns. Growth releases on increment cores suggested that peak periods of growth releases indicating partial canopy disturbances have repeatedly occurred over the past 230 yr at intervals from ca. 35 to 100 yr. Slight releases and suppressions other than the peak releases occurred in many years of both histories, suggesting the formation of smaller-scale canopy gaps. Despite the predominance of anthropogenic fires in Primorskiy Kray at present, destructive fires had not affected either forest. Wind disturbances and low intensity fires are likely factors controlling the dynamics of the forests. Under the disturbance regime, P. koraiensis has maintained its populations through its dependence on canopy gaps for establishment. Age distribution and gap dependence of P. ajanensis, A. nephrolepis and A. mono suggested continuous establishment of these species under a closed canopy, whereas occasional establishment of T. amurensis was derived largely from vegetative reproduction. Restricted establishment of A. holophylla and B. costata suggested a variety in kinds of disturbance throughout the histories. Continuous habitation of the study area by P. koraiensis is likely under the disturbance regime without destructive fires.

A phytosociological survey of the deciduous temperate forests of mainland Northeast Asia

This study represents the first survey of the temperate deciduous forests of mainland Northeast Asia on the territories of the Russian Far East, northeast China and Korea. A total of 1200 relevés are used, representing nemoral broadleaved (Fraxinus mandshurica, Kalopanax septemlobus, Quercus mongolica, Tilia amurensis)-coniferous (Abies holophylla, Pinus koraiensis) forests, and broadleaved Quercus spp. forests. The vegetation is classified into 4 orders, 12 alliances, 50 associations, 36 subassociations and 8 variants. One order, Lespedezo bicoloris-Quercetal ia mongolicae, 4 alliances Rhododendro daurici-Pinion koraiensis , Phrymo asiat icae-Pinion koraiensis , Corylo heterophyllae-Quercion mongolicae and Dictamno dasycarpi-Quercion mongolicae, and 14 associations are described for the first time. The communities are placed into two classes. Quercetea mongolicae reflects monsoon humid maritime climate with the amount of summer precipitation higher than winter precipitation and the lack of a period of moisture deficit. They occur in Korea, montane regions of China east of the Lesser Hingan and the Sikhote-Alin. Querco mongolicae-Betuletea davuricae unites forests in conditions of semiarid subcontinental climate with summer precipitation considerably higher than winter precipitation and with the period of moisture deficit in spring and early summer. They occupy mostly the regions of northeast China and eastern Russia west of the Lesser Hingan and in the low elevation belts of the southern Sikhote-Alin.

Phytosociological study of thePicea jezoensis forests of the far east

Forest communities dominated byPicea jezoensis (Yezo spruce) are described from across their entire distributional range in eastern Asia, including the territories of the Russian Far East and Japan. A total of 476 relevés are used representing the following dominant types of spruce forests: pureP. jezoensis, mixedP. jezoensis andAbies sachalinensis, mixedP. jezoensis andAbies nephrolepis, and purePicea glehnii communities. The vegetation is classified into 11 associations, 2 community types, 6 subassociations, 25 variants and 8 subvariants. Nine associations, including theAsaro heterotropoidis-Abietetum sachalinensis, Weigelo middendorffianae-Piceetum jezoensis, Lysichito-Piceetum glehnii, Swido albae-Piceetum obovatae, Oplopanaco elati-Piceetum jezoensis, Philadelpho tenuifolii-Piceetum jezoensis, Vaccinio-Piceetum jezoensis, Rhododendro aurei-Piceetum jezoensis, andMoneseto uniflorae-Piceetum jezoensis, are described for the first time. The ecology and structure of all communities are described and their syntaxonomy discussed. The communities are placed in three alliances,Piceion jezoensis, Abieti nephrolepidis-Piceion jezoensis andPino pumilae-Piceion jezoensis, all. nov. All of the communities described are considered to belong to the orderAbieti-Piceetalia of the classVaccinio-Piceetea.

Characterization of nutrient regimes in some continental subalpine boreal forest soils

To determine whether field-identified soil nutrient regimes (SNRs) can be characterized and segregated by direct soil nutrient measures, we collected samples of forest floor and mineral soil (0 to 30 cm) from a wide range of forest sites throughout the Engelmann Spruce — Subalpine Fir (ESSF) zone of British Columbia. The samples were analyzed for acidity, total C, total N, mineralizable N, and extractable Ca, Mg, K, P, and SO4-S. The study sites were stratified according to an a priori field classification (SNRs) and an a posteriori classification derived from quantitative classification (groups) using all direct measures of nutrients as discriminating variables. The two classification methods had 72% agreement. Regardless of the classification, nitrogen-related variables (C:N ratio, total N, and mineralizable N) in the mineral soil segregated best among SNRs or groups indicating the presence of a steep, N-driven regional soil nutrient gradient. Multiple regression models using SNRs, groups, or direct mea...

Phytogeography of Northeast Asia

Northeast Asia as defined in this study includes the Russian Far East, Northeast China, the northern part of the Korean Peninsula, and Hokkaido Island (Japan). We determined the species richness of Northeast Asia at various spatial scales, analyzed the floristic relationships among geographic regions within Northeast Asia, and compared the flora of Northeast Asia with surrounding floras. The flora of Northeast Asia consists of 971 genera and 4953 species of native vascular plants. Based on their worldwide distributions, the 971 genera were grouped into fourteen phytogeographic elements. Over 900 species of vascular plants are endemic to Northeast Asia. Northeast Asia shares 39% of its species with eastern Siberia-Mongolia, 24% with Europe, 16.2% with western North America, and 12.4% with eastern North America. Species richness and floristic relationships among different regions within Northeast Asia were discussed. The northernmost (Arctic) region shares 64% of its genera and 9% of its species with the southernmost (warm temperate) region. The geographic setting, climate, vegetation, and endemism of each of the eighteen regions of Northeast Asia were described and characterized. The geographic distributions of the 53 most important tree species in Northeast Asia were mapped.

Classification and ecology of the mid-seral Picea mariana forests of British Columbia

Abstract We sampled vegetation and soils of, and classified mid-seral, even-aged, fire-origin, upland Picea mariana ecosystems in the Boreal White & Black Spruce and Sub-boreal Spruce zones of British Columbia, Canada. We applied multivariate and tabular methods to analyse and synthesize the data from 121 plots according to the methods of biogeoclimatic ecosystem classification. We delineated seven basic vegetation units and described their vegetation and environmental features. However, the delineated units could not be related to neither of the taxonomies proposed for the North American boreal forest communities. Although species-poor, the understorey vegetation in the sampled ecosystems provided for a sufficient floristic differentiation, which matched well the major edaphic differences between the units. The classification of mid-seral boreal ecosystems may be more useful that based on old-growth stands that are infrequent or lacking in the landscape due to wildfires. Abbreviations: BC = British Columbia; NMDS = Non-metric multidimensional scaling; SMR = Soil moisture regime; SNR = Soil nutrient regime. Nomenclature: Qian & Klinka (1998).

The subalpine vegetation of Mt. Vysokaya, central Sikhote-Alin

The subalpine vegetation structure of Mt. Vysokaya, the Central Sikhote-Alin, is described. This vegetation consists mainly of subalpine spruce-fir forest, a complex of subalpine meadows, shrubs, groves of Betula lanata (B. ermanii s.l.), krummholz of Pinus pumila and alpine tundras. Significant disturbances in the vegetation structure were noted, especially in the forest-tundra ecotone accompanying a sharp reduction of the belts of Betula lanata and Pinus pumila. The altitudinal level of the upper timberline reaches 1600 m a.s.l. which is 250 m less than the expected altitude calculated by Kiras warmth index. An undergrowth of scattered trees of Picea and Betula are growing up to the mountain top. Based on these data and a review of the literature, we concluded that a catastrophic lowering of the timberline and devastation of the subalpine vegetation belt occurred several centuries ago, probably as result of fires.