Main Problem Zones and Challenges

Up one level

2. MAIN PROBLEM ZONES AND CHALLENGES

 

Over the last years, a mixed economy has been formed within agrarian-industrial complexes of Ukraine and Russia, the majority of enterprises have been re-organized, productive and land relations have been reformed and land use boundaries have changed. These changes have affected economic and commercial activities, planning of territories, cultivation area composition, farming and agricultural production systems in general. The application of mineral fertilizers and pesticides has reduced tenfold, the use of organic fertilizers – by several times.

 

All of the above factors combine in changing the environmental situation in agrarian landscapes, undermine the ecosystem stability and, thus, necessitate the development of new approaches to environmental protection and conservation. In this respect, the Dnipro Basin deserves special attention.

 

The conducted analysis testifies that soil landscape is used unsustainably in the Dnipro Basin. On the one hand, specialization of agricultural production characteristic of the former planned economy that tended to ignore environmental implications of unsustainable land use is still in place in many regions. The specialization presupposed an intensive development of one or several branches of plant growing or cattle breeding, which limited the use of environmentally friendly planning of territories by agricultural enterprises, administrative districts and oblasts.

 

On the other hand, following the deep crisis in agriculture, the system of controlling the activities of agricultural producers and land planning services collapsed. Therefore lands within water-protecting zones and riversides have been used unsustainably for household farming, building summer cottages and small processing enterprises, as well as for organizing small farms. The planting of water protecting forest and shrub belts has stopped.

 

In view of the above, approaches to agricultural practices and land use planning in the Dnipro Basin should be urgently revised and reformed.

 

The Dnipro Basin total area in the territories of Ukraine, Russia and Belarus is 511.8 thousand square kilometers. Agricultural land occupies 31,082.6 thousand hectares (60.7% of the total basin area, see Table 2.1 and Figure 2.1), of which 22,925.3 thousand hectares are plough lands (44.8%, Figure 2.2).

 

Table 2.1. Agricultural development rate of the Dnipro Basin lands

 

 

These lands have a relatively high natural fertility rate, the majority of them can be used for effective land farming and cattle breeding. At the same time, the agricultural development and ploughing-up rates of the Dnipro Basin territory (especially in Ukraine) are extremely high, exceeding by many times the corresponding indicators found in the developed countries of the world. Since these lands are intensively ploughed up, the biological diversity in the region is adversely affected, the anthropogenic load on the landscapes is growing, which, in its turn, leads to the degradation of the latter.

 

In terms of global environment, the alleviation of anthropogenic load (pressure) is viewed as a sought outcome of conservation activities, as one of strategic objectives of environmental stabilization and safety. Understandably, the reduction of agricultural activity scopes can only be auspicious if the lands are used in a sustainable manner and natural biological and geographical sites typical for the region in question are formed.

 

Weakened state control of ecosystems is one of the factors contributing to depletion of species composition and extinction of numerous species. The exhaustion of ecosystems, reduction of their species diversity is harmful for their stability. Short-term consequences of reduced species diversity may not be quite obvious, yet in the long run they can cause environmental disasters.

 

The fact often overlooked in analyzing environmental challenges is that the ecosystem stability factor depends, to a great extent, on the volumes of primary production per area unit, i.e. on the gross photosynthesis production. It is commonly believed that the gross photosynthesis production for the Earth is, in general, relatively stable, although this stability can be threatened, given the growing СО2 concentrations in the atmosphere.

 

This matter may seem to be of a theoretical rather than practical nature. Yet this is the first impression. A deeper insight will reveal that the amount of bound solar energy determines the quantity of organic substance received by soil. The decreased receipt part in the balance of organic substance can lead to the reduction of humus content in the soil and, thus, reduction of soil fertility. The loss of soil fertility inevitably entails soil degradation, diminished stability of functioning ecosystems, and their replacement with less valuable ones having a lower energy balance (see Figure 2.2).

 

Soil in the Dnipro Basin is highly eroded. The areas of eroded plough land expand from the upper flows of the river southwards (see Table 2.2 and Figure 2.3). Among the natural and agricultural regions most affected by water erosion are the steppe and forest-steppe zones of Ukraine.

 

Table 2.2. Erosion rate of the Dnipro Basin lands

 

 

* – Eroded and erosion-susceptible lands

 

 

 

A reversed regularity is observed in respect of the areas of waterlogged lands. In the Upper Dnipro Basin, waterlogged lands, naturally, occupy larger areas (Table 2.3 and Figure 2.4). Part of them was drained, but they have not been used effectively over the last years.

 

Table 2.3. Bogginess of the Dnipro Basin territory

 

 

As for the current state of ameliorated systems, it can hardly be characterized as satisfactory. No new systems are being set up, the old ones being in need of urgent and comprehensive reconstruction. 15% of irrigated lands suffer from flooding in spite of the dramatic reduction in watering caused by the shortage of sprinkling equipment, high cost of fuel, lubricants and electricity. Secondary salinization is observed in 7%-8% of total area of irrigated lands, while soil alkalinization – in 25%-35% of their area. Almost universally, irrigation has resulted in de-humification and soil disturbance.

 

Approaches to land drainage have two essential aspects to them. On the one hand, until the 1990s, the areas of drained land were expanded to a maximum possible size, often with no regard of double regulation of water regime or of a special role waterlogged ecosystems have to play in conserving wildlife habitats and natural flora, as well as in regulating hydrological regime of the territory. Deep irreversible drainage, unreasonably big share of intertilled crops in the crop composition and minimum share of perennial herbs lead to an unusually rapid mineralization of peat formation coupled with the loss of peat layer, susceptibility to deflation, surfacing of infertile, sometimes even toxic gley soil (with high content of ferric oxide).

 

Looking critically at the current practices of involving waterlogged lands in agricultural use, one cannot deem them expedient for a number of reasons [5]. The majority of these lands are adjacent to Polessye (forest) zone, with its specific landscapes constituted by intermingling marshy lowlands and sandy upland accumulations. The lowland periphery is represented by semi-hydromorphic, light texture soils that, when in their natural condition, are the most productive. As a rule, drainage of waterlogged territories leads to the change in the overall hydrology of such landscapes, the ground water depression curve often going beyond the perimeter of intended drainage. The soil moisture level on the lowland periphery drops significantly, and the soil there, having light texture, and, consequently, low moisture-holding capacity, loses fertility. Thus, the economic effect of drainage proves much less than initially estimated. The above applies to economic aspects of drainage, which, in every particular case, should take into account the character of ameliorated landscapes, including their hydrological indicators, and the correlation between the area of waterlogged lands and that of lands with peripheral semi-hydromorphic soils, as well as the soil qualities, fertility and prospects of further use (following drainage). In environmental terms, it seems essential that Polessye zone is a basin (trough) where the amount of water depends on the accumulation of snowmelt of the last glacierization. The discharge of sub-surface water in the course of drainage, which in some cases is not sufficiently substantiated, can be detrimental to the overall humidification of Polessye landscapes and, given the hydro-physical soil characteristics, to the productivity of those landscapes at large. Under the circumstances, irreparable harm is done to biodiversity.

 

Bogs and marshes are specifically positioned between the minor biogenous and major biological circulation of substances; they transfer CO² from biogenous circulation into biological one and remove it from the atmosphere 7-15 times as effectively as forests do. When drained, peat bogs, instead of removing CO² from the atmosphere, start polluting it, thus aggravating the greenhouse effect [6,7].

 

Secondary bogging-up, observed in some areas and caused by the worsened functioning of the existing drainage systems, can be considered favorable for the environment, since it is usually accompanied with the decrease in river basin contamination with agro-chemicals, reduction of eutrophication scope, restoration of the population and species composition of water fauna, etc. Unfortunately, these processes have not been studies lately, although research in this area is critical. According to the findings of fragmental environmental monitoring, in spite of the reduced contamination from agricultural production, the general contamination with chemical toxicants remains high, and sometimes even grows. The reason lies in the renewed operation of local industrial enterprises, in particular of chemical ones, and in the transboundary toxicant transport with atmospheric masses, coming from the industrially developed European countries.

 

The outcomes of the above environmental monitoring testify that the soils of the basin, especially on the Dnipro flood lands near Dorogobuzhsky industrial complex in Smolensk Oblast and in Dnipropetrovsk Oblast, are contaminated very considerably [8, 9].

 

Over the last ten years, the content of many contaminants in the water of the Dnipro and its tributaries has risen noticeably and exceeded the established maximum admissible concentrations. Among such contaminants are ammonium (exceeding MAC by 22 times), nitrates (76 times), oil products (12-42 times), phenols (14-71 times), heavy metals (5-134 times) and organochlorine pesticides (2-72 times).

 

The general level of the Dnipro water mineralization has increased, if slightly. The concentrations of copper and zinc in water are fairly high along the whole river. High concentrations of iron and manganese have been registered in the river water near Dnipropetrovsk. Phenol concentrations surpass the admissible levels on the entire basin area. In the zones of intensive agricultural production (especially in the southern part of the Basin) the Dnipro suffers from man-caused contamination with chemicals released into the river together with surface flows and wastewater discharges from water treatment facilities of agricultural enterprises that are, for the most part, inefficient. Great amounts of nutrients and pesticides have accumulated in bottom sediment of the Dnipro water reservoirs. In summer months of low flow, these contaminants return to the river water and are carried down the flow. Thus, high metal concentrations in the bottom sediment were registered in samples from the Konoplianka, Vorskla and Mokraya Moskovka Rivers. Pesticide contamination of various concentrations was observed in water and bottom sediment samples from estuary parts of fourteen Dnipro tributaries. In more than half of the Dnipro tributaries, the concentration of organochlorine pesticides exceeded the MAC established for fisheries.

 

As mentioned above, plough lands cover 44.8% of the total basin area. Disproportionately high rates of their agricultural development and ploughing-up contribute a lot to the destabilization of environmental situation in the Dnipro Basin.

 

 

Agro-landscape environmental stability is known to depend directly on how well preserved its natural phyto-coenoses are. Environmental stability and territorial anthropogenic load factors were used to assess the state of land resources as regards their potential and actual susceptibility to anthropogenic loading (pressures). The latter factor¹⁾ is a calculated indicator reflecting the shares of lands with different environmental stability (forests, shrubs, meadows, pastures, marshes, reserve land, etc). Based on this factor, the northern and western parts of the Dnipro Basin can be assessed as relatively stable, whereas the southern part is the most vulnerable (susceptible).

 

Figure 2.5. Environmental stability factor of the Dnipro Basin territory (as of 2002)

 

 

Land composition analysis, particularly in what concerns agricultural land, reveals an imbalanced composition harmful for the land quality and fertility.

 

On the other hand, the share of plough lands is gradually decreasing, while the area of forage grasslands and forest plantations (i.e. environmentally stabilizing lands whose ecosystems function like natural ones, under the minimum anthropogenic impact) is growing, which can be considered a sign of an improving environmental situation. So, a broad-scale re-naturalization of the environment seems to be under way in the region, conducive to the environmental optimization of land use.

 

Since natural-climatic conditions in the Dnipro Basin are varied, it is necessary to develop an environmentally optimized land composition at the most representative territorial level characterized by uniform natural and economic conditions. The unit meeting these requirements is natural agricultural district (zone) – the smallest taxonomic unit of the natural-and-agricultural zoning [10].

 

Ukraine seems to have a land reserve composition, categorized by all land users and land owners for different natural agricultural zones (districts), which is the most destabilizing for the Dnipro Basin biodiversity (Table 2.4,% of total area). Tables 2.5, 2.6 and 2.7 show environmental stability and ecological load factors of the land reserves in the Ukrainian, Russian and Belorussian parts of the Dnipro Basin.

 

These are baseline data for developing the optimized structure of land resources use, their distribution by lands and environmentally sustainable territory planning.

 

Table 2.4. Land composition in the Ukrainian part of the Dnipro Basin, %

 

 

 

Table 2.5. Environmental stability and anthropogenic load factors in the Ukrainian part of the Dnipro Basin (as of 2002)

 

 

 

Table 2.6. Environmental stability and anthropogenic load factors in the Russian part of the Dnipro Basin (as of 2002)

 

 

Table 2.7. Environmental stability and anthropogenic load factors in the Belorussian part of the Dnipro Basin (as of 2002)

 

 

Thus, steppe and forest-steppe zones within Ukraine’s territory appear to be the most unstable ones in respect of conserving biodiversity on agricultural lands (see Table 2.5).

 

The total area of agricultural lands in the Dnipro Basin adversely affected by water erosion is 4.9 million hectares, including 4.0 million hectares of plough lands (constituting 26% of the total area of these lands). 1.7 million hectares of eroded lands have medium and highly eroded soils. Of special concern are the erosion scale and intensity on black and other fertile soils.

 

The area of eroded plough lands in the basin expands by 30-50 thousand hectares per year, the expansion rate of the area of medium and highly eroded soils being especially high. Annual losses of fertile continuum of plough land in the Dnipro Basin amount, on the average, to 14 thousand hectares. In a number of territories in the forest-steppe zone, these losses are even higher, at 20 thousand hectares per year. In general, 220 million tons of soil, with over 9 million tons of humus and 5 million tons of nutrients, are annually washed off the plough lands (on the average, 6 centners of humus and 3 centrners of nutrients are washed off from every hectare of plough land). Erosion products are partly accumulated in the gully network, partly are transmitted into the Dnipro and its tributaries, thus causing the silting of water bodies and their contamination with organic compounds and agro-chemicals.

 

Analysis of the change in soil humus content over time testifies that over the last 20 years the (absolute) humus content in plough land reduced, on the average, by 0.3%, in the steppe zone sometimes by 0.4%-0.6%.

 

Erosion of pastures is slower and less intensive. However, the unrestricted cattle grazing leads to grass sod depletion, which, in its turn, catalyzes erosion processes.  Alongside flat land erosion, intensive processes of linear corrosion and gully-formation are under way.

 

The area of active gullies approaches 100 thousand hectares. The waterfront of the Dnipro water reservoirs extends for over 3 thousand kilometers, 1100 kilometers of which are eroded escarpments in need of urgent stabilization, as over 6 thousand hectares of land have already been lost to bank erosion, accompanied with the inflow of 400 million cubic meters of bank erosion products into the water reservoirs.

 

Over 3 million hectares of land are systematically subject to wind erosion, while up to another 10 million hectares – to dust storms. Dust storms annually occur in Donetsk, Zaporizhzhia and Kharkiv oblasts.

 

Other quality indicators of land reserves (salinization, alkalinity, excessive moisture content, etc) also tend to deteriorate. Thus, according to the State Committee of Ukraine for Land Resources, in the Dnipro Basin 4.8 million hectares of plough land (24.7%) have acid soil, 1.1 million hectares (5.7%) have alkaline soils and 675 thousand hectares (3.4%) have saline soil. Besides, 829 thousand hectares of agricultural lands have soil with excessive moisture content, 904 thousand hectares have waterlogged soil and 170 thousand hectares have stony soil.

 

While in 1985-1990 lime was annually applied at over 1.5 million hectares of acid soil, average doze being 5 tons per hectare, nowadays lime application has practically ceased.

 

The monitoring findings testify that a long-term agricultural use of lands with especially valuable soil accelerates dramatically (due to increased microbiological activity) the bio-geo-chemical cycle processes, changing (i.e. speeding up) the soil-formation rhythm (see Table 2.8). As a result, soil needs to be constantly supplied with energy material. Absence of such supplies on fallow lands and their shortage on plough land were offset by mobilizing all other available resources, which has eventually led to depletion and drop in fertility of ploughed land, as well as to the break down of the initial biodiversity balance in these soils.

 

Table 2.8. Microbial coenoses of natural and agricultural ecosystems

 

 

Another evidence of reduced biodiversity in the region is the fluctuation in bird populations in the biosphere reserve “Askaniya Nova”. Located close to virgin lands under special protection treatment, this reserve has been used over the last forty years as a site for observing changes in biodiversity in the zone of man-made landscapes where forest and wetland biotopes have been formed resulting from large-scale irrigation. The introduction of semi-natural biotopes into steppe habitats is conducive to a growing species diversity, the tendency having been revealed at the early stages of avifauna study in the reserve [11,12]. Analysis of findings at those stages and their comparison with the contemporary data show that at the early stages the number of species grew, while later certain species were extinct. A dramatic change in the populations of bird species has also been observed. Anthropogenic factors had a great impact on bird populations that immigrated to the steppe zone from other natural zones, since they started settling in the new territory, which was often limited in space. Two contrary processes have been observes over the last 10 years: re-naturalization, on the one hand, and destruction, on the other, both being fairly pronounced. Since the early 1990s, agricultural production in the region has declined, which has affected the condition of plough lands. At the same time, direct impact on wildlife has intensified because of biotope transformation and uncontrolled hunting. Moreover, natural factors, including climatic ones, have contributed noticeably to periodical substantial biotope changes, which, in their turn, distress avifauna. Birds are one of the most sensitive indicators of the environmental situation. Several observations have been made of their ability to differentiate protected territories from those were hunting was allowed. In humid years, for example, qualitative and quantitative characteristics of bird populations commonly improve. Thus, before describing the most essential changes in the avifauna of “Askaniya Nova”, it seems appropriate to give a brief outline of the factors that have caused the said changes. Among these factors, directly or indirectly linked with human activities, are the following:

 

- shrinkage of irrigated land acreage leading to the decreased fertility and productivity of agricultural lands, reduced amount of crop residue and concentration of some bird species within a limited areas under crop, the latter experiencing excessive loading;

- reduction of rice-growing areas resulting in dry-up of waterlogged territories and, thus, in decreased waterfowl populations or their stopping to nestle in the region;

- total burn-down of stub-land destroying nestling places;

- annual massive burn out of forest belts damaging protective and nutritious properties of these biotopes and affecting both settlements of passerine and predatory birds in the nestling period and their stop-over sites during migrations;

- ploughing-up of the remaining virgin land along Lake Sivash coast bringing about the change in biotopes of steppe species.

- Factors relating to re-naturalization processes seem to be as follows:

- increased acreage of weed-grown lands;

- unstable weather conditions and their direct or indirect impact; increased or decreased atmospheric precipitation;

- raised annual precipitation rate;

- flooding of some lands because of drainage systems breakdown, etc.

 

In some years, certain species may actively settle in the area, their populations growing for two-three years and then going down, almost to extinction.

The available data testify that the qualitative composition of biodiversity on agricultural lands is rapidly deteriorating in entire territory of the Dnipro River Basin. Its current condition can be assessed as pre-critical, tending towards progressive aggravation.

 

 

^{______________________________}

1)       Environmental stability (ES) is calculated based on the agro-landscape stability criterion and on assessment of different types of land against this criterion. A system of factors, reflecting the environmental importance of each land type and ranging from 0 for developed lands to 1 for forests, has been designed [12]. The ES level of each specific area is determined by calculating mean weighed ES factor on the basis of the current land composition. If the obtained value is less than 0.33, the territory is assessed as environmentally unstable; if it varies within the range 0.33-0.5, the territory is stable-to-unstable; if it does not exceed 0.5-0.66, the territory is of medium stability; the territory is considered environmentally stable if the obtained value is 0.66 and more.