Comparison of commonly used ecological scales with the Belgard Plant Ecomorph System

There are several ecological scales developed both for phytoindication of ecological factors and plant ecomorphs. Among them, the scales of Ellenberg and Tsyganov are the most commonly used. L. G. Ramensky and P. S. Pogrebnyak had developed a phytoindication method; they also were founders of first ecological scale of plant species in relation to various environmental factors. One of first ecomorph systems was developed by Alexander Lyutsianovich Belgard. In 1947, Belgard presented a tabular ecomorph system in his doctoral dissertation, and later in monograph “Forest vegetation of the South-East of Ukraine”. In the system he used abbreviated Latin names applying terminology proposed in the late 19th century by Dekandol, Warmin and other authors. He considered ecomorphs as adaptations of plants to environmental conditions in forests of the steppe zone of Ukraine where forest cenoses are exposed to processes of steppization, prairification, swamping, salinization, and thus clarification of relationships between forest, meadow, steppe, marsh and weed plant species was essential. Therefore, development and introduction of cenomorph terms as “adaptation of plant species to phytocenosis as a whole” were an absolutely new contribution to the concept of ecomorph system. In environmental factor scales of Ellenberg and other authors, environment characteristics based on phytoindication were underlined; in the Belgard Plant Ecomorph System, ecomorphs reflect ability of plant species to grow within certain ranges of a given factor. These approaches are quite comparable, and ecomorphs of the Belgard system correspond to certain grades of the Ellenberg and Tsyganov scales. The Belgard ecomorph system has been applied in a number of fundamental and applied works on plant ecology and phytocenology. It is convenient for characterizing ecological features of plant species growing in the steppe zone with a wide range of environment factors such as lighting, humidity, and soil richness. Other authors have expanded and supplemented the Belgard Plant Ecomorph System based on its strategy. A number of ecomorphs was introduced; they reflect intermediate or extreme gradations of factors. A new cenomorph – silvomargoant – has been proposed by the authors of this paper.


History of phytoindication scales and ecomorph systems
A large number of environmental scales currently exist.On the one hand, they are intended for phytoindication of ecological factors, and on the other, as a system of plant ecomorphs (Dіduh & Pljuta, 1994).One of first ecomorph systems was developed by Alexander Lutsianovich Belgard on the basis of concepts of D. I. Mendeleev, V. V. Dokuchaev, V. N. Sukachev.Together with his teacher G. N. Vysotsky, Belgard developed a new branch of science "Steppe Forestry".The Belgard Ecomorph System was presented by the author in his doctoral dissertation "Forests of South-Eastern Ukraine" in 1947, and then in his monograph "Forest Vegetation of South-Eastern Ukraine" (1950).In development of the ecomorph system he applied known terminology and abbreviated Latin plant names (Belgard, 1950).For nearly 70 years, this ecomorph system has been successfully applied in survey and characteristics of cenoses of both specific biotopes and landscapes.The Belgard Ecomorph System was developed in a number of fundamental works on plant ecology and phytocenology.It can be quite wide ranging: in assessment of phytocenotic structure, in ecological characteristics of flora on supracenotic levels, as well as in assessing the state of the environment with the main physical and chemical parameters.
Other authors have expanded and supplemented the Belgard Plant Ecomorph System based on its strategy.A number of ecomorphs reflecting intermediate or extreme gradations of factors have been introduced into the system.A new cenomorph -silvomargoant -has been proposed by the authors of this paper.There is a practical need for expanding the Belgard Plant Ecomorph System and further introduction of additional ecomorphs.The objective of this work was characterization of the peculiarities of the Belgard Plant Ecomorph System (including its supplemented version) and its advantages in comparison with the scales of Ellenberg and Tsyganov.Ramensky was founder of the phytoindication method that is based on the use of species composition of vegetation.He was also originator of the first ecological scale of plant species in relation to various environmental factors (Ramenskiy, 1929).According to Tsyganov (1983), "works of Pogrebnyak and Ramensky are sources of European scoreand-scale methods in ecological analysis.The first scientific work of Pogrebnyak including justification of his methodology was published in 1927.The first scientific work of Ramensky where he justified and applied in detail an ordinary coordination method was published in 1929, i.e. much earlier than similar works of Ellenberg and other European researchers." Pogrebnyak (1955) proposed an ecological scale of tree species, Ramensky (1956) developed detailed ecological scales of soil humidity, richness and salinity of meadow plant communities.
The scales are divided into point and amplitude scales.The point scale indicates the ecological range of plant species by a particular environmental factor.The amplitude scale determines the coordinate of plant species on the axis of environmental factor.

Table 1
General characteristics of ecological scales (by Diduh & Pljuta, 1994) Author Total score in the scale Hd fH Tr Rc Nt Gm Ar Tm Om Kn Cr Lc Dg Ellenberg 12 -3 9 9 --9 -9 -9 -Landolt 5 4 2 5 5 5 5 5 -5 -5 -Zoiomi 11 --6 ---7 -2 ---Frank & Klotz 12 2 3 9 9 --9 -9 -9 -Zazhitskii* 6 -3 6 5 5 5 5 -5 -5 - Belgard presented his ecomorphic system of vascular plant species in relation to the main environmental factors with the purpose of classifying ecological characteristics of forest communities in the steppe zone of Ukraine (Belgard, 1950).In 1947, A. L. Belgard presented a tabular ecomorphic system in his doctoral dissertation, and then in his monograph "Forest vegetation of the South-East of Ukraine" (1950).The author developed an ecomorphic system using terminology proposed in the late 19th century by Decandol (Dekandol, 1956), Warming (Warming, 1903), and by other authors.The Tabular Belgard Plant Ecomorph System was compiled for the main environmental factors: light intensity (heliomorphs), temperature (termomorphs), humidity (hygromorphs), soil richness (trophomorphs).The author designated names of ecomorphs with abbreviated Latin names of environmental factors.Tabulated ecomorphic analysis of plant species within a community or system of supra-cenotic level (ecological certification of species) gives insight into the ecological structure of flora (Table 2).Note: plant species names are given in accordance with the nomenclature of Mosyakin & Fedoronchuk (1999) Alexander Grossheim, famous botanist, author of Angiosperm Phylogeny Group Classification (1946), emphasized the following: "The advantage of the ecological analysis method proposed by A. L. Belgard resides in the fact that it covers all the most important environmental factors affecting the existence of plant species in a phytocenosis.
Usually, a more vivid impression is obtained on application of the ecomorphic method in a phytocenosis.According to A. L. Belgard, the characteristic of cenose is multisided in this case.In application of the author's formulae and graphs, interrelations existing in nature have many-sided coverage, due to which maximum approximation to the truth is obtained in comparison with the use of other, usually one-sided methods".

Correspondence of the Belgard Plant Ecomorph System to other environmental scales
Ecomorphs are considered by Belgard (1950) as adaptations, adjustments to environmental conditions (Belgard, 1950).Belgard's scheme "was made specifically for forest survey in the steppe zone of Ukraine, where forest cenoses are often exposed to processes of steppization, prairification, swamping, salinization, spread of weeds, and where it is important to find out the relationships between forest, meadow, steppe, marsh and weed species" (Belgard, 1950).
Choice of ecological scale largely depends on geographical area, biotopes studied and survey specificity.Environmental characteristics associated with phytoindication form the basis of scales of primary factor regimes developed by Ellenberg and other authors.But in the Belgard system, one or another ecomorph reflects the ability of plant species to grow in certain ranges of factors' influence, i.e. it serves as an ecological characteristic of the species.These approaches are quite comparable, and ecomorphs of the Belgard system correspond to certain gradations of the Ellenberg and Tsyganov scales (Table 3-6).Differences in these systems concerning the meaning of soil richness are based on specificity of geographical areas for which the scales have been developed.Authors apply concept of nitrogen richness to the forest zone when soils are characterized by low level of mineralization and a large amount of slowly biodegradable organic matter.For the steppe zone, the concept of soil richness reflects its total nutrient content because soils with greater mineralization and decomposition of organic matter are formed within this zone.And the presence of highly mineralized soils is reflected by the cenomorph of high salinity (alkotrophs).
The systems of Ellenberg and Tsyganov were developed for phytoindication of forest plant communities within the forest zone.And Belgard's system of ecomorphs was developed for survey of forest plant communities in the steppe zone.On the one hand, it meets the requirements of these ecosystems, and on the other hand, it is more suitable for phytoindication of different types of plant communities (forest, steppe, meadow, marsh, aquatic, etc.).The Belgard Plant Ecomorph System has a wider range of environmental factors in forest phytocenoses of the steppe zone.It is particularly convenient and can be successfully applied for data processing in ecological analysis both of individual plant communities and flora in large areas (supracenotic level) having considerable species richness.For a more convenient analysis, Matveev suggested a numerical equivalent of ecomorphs (Matveev, 2006).

Application and development of Belgard's Plant Ecomorph System
The Belgard Plant Ecomorph System was applied in several fundamental and applied scientific works on plant ecology and phytocenology (Tarasov, 1981(Tarasov, , 2012;;Matveev, 1995Matveev, , 2006;;Baranovsky, 2000;Еko-flora Ukrajiny, 2000;Brygadyrenko, 2016;Baranovsky et al., 2017).Belgard's scale is applied to characterize the environmental features of plant species in the steppe zone with a wide influence range of environmental factors such as moisture, soil richness, mineralization.
Vascular plant species of forest clearings present a special ecomorph due to the specificity of natural conditions in this biotope.This is especially true of forest clearings of the steppe zone where the lack of moisture as a limiting factor is more significant and manifests itself in more distinct gradations.Vegetation of forest margins and clearings had previously been allocated in a separate group (Rastenija lesnih poljan i opuschek, 1986).Previously, in ecomorphic analysis the authors attributed these plants to steppe or forest species (Baranovsky, 2000;Matveev, 2006;Tarasov, 2012).However, the majority of these species classified as stepants are not typical representatives of steppe biotopes, and species classified as sylvants almost never occurred in the undergrowth.

Conclusion
The Belgard Plant Ecomorph System has its own characteristics, but it corresponds to the more widespread systems of Ellenberg and Tsyganov.It includes fewer gradations of environmental factors, so it is more applicable for phytoindication of different plant associations, especially for large areas.Its advantage is that the letter designation of ecomorphs gives the possibility to tabulate calculation of ratio between plant species of different habitats.The Belgard Plant Ecomorph System is especially suitable for characterizing ecological features of higher plant species in biotopes of the steppe zone with a wide range of such factors as moisture and mineralization.The Belgard scale covers specifically a wide range of influence of environmental factors.In his ecomorph system, A. L. Belgard first used the term "cenomorph" which indicates the confinedness of a species to a particular phytocenosis.Multi-year studies and analysis of reported and archival scientific materials allow us to propose new ecomorphs for extreme values of factors and separate a new cenomorph -sylvomargoant -in the context of development of the Belgard Plant Ecomorph System.Botanists and ecologists of Oles Honchar Dnipro National University are successors of Belgard's scholarly traditions.Currently, "ecological passports" have been developed for almost 2,000 vascular plant species of the steppe zone of Ukraine.In this paper, we set ourselves the task of acquainting our colleagues and revealing as fully as possible the essence of Belgard's Plant Ecomorph System.Application of the methodology of this system, as well as the ecomorph system itself, can be useful and applicable by our foreign colleagues.

Table 3
Light intensity factor according to Belgard's Plant Ecomorph System in comparison with other ecological scales Note: ** -amendments ofMatveev (2006).

Table 6
Trophicity factor according to Belgard's Plant Ecomorph System in comparison with other ecological scales

Table 7
Cenomorphs according to Belgard's Plant Ecomorph System in comparison with other ecological scales