Influence of Human Activities and Demographic Trends on the Environment of Grdelicka Gorge (South...

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BALWOIS 2010 - Ohrid, Republic of Macedonia - 25, 29 May 2010 1

Influence of Human Activities and Demographic Trends on the Environment of Grdelicka Gorge (South Serbia)

Miodrag Zlatić1, Milena Lakićević1, Jelena Tomićević1

1Faculty of Forestry of Belgrade University, Serbia

Abstract

As worldwide the major factor in provoking degradation of natural resources in Serbia is the anthropogenic. Special attention in the paper is given to the soil degradation emphasising example of Grdelicka Gorge, being one of the areas most endangered by erosion in Europe in the mid fifties of the last century.The development of erosion processes can be devided into the period until 1950s and from the mid 1950s to the present day (Zlatić, 1998 ). The first period was characterized by the highest agrarian pressure and accelerated erosion. The basic demographic-economic problematics of hilly-mountainous area of Grdelicka Gorge is being reduced to the disproportion between the number of the agricultural population and the soil areas at disposal, i.e. the manner of agricultural production. This disproportion has resulted also in others, such as: the population – number of livestock, the areas – number of livestock, etc. It is however the man to soil, i.e. land use disproportion , that remains as the most important one.

The second period was characterized by population migration, large extent of erosion control works, changes in the structure of agriculture production and, as the consequence, the decline of erosion intensity. The high agrarian pressure in investigated area was primarily reduced by migrations. As younger household members migrated, arable fields were left uncultivated, invaded by weeds, and converted into pastures which contributed to diminishing erosion. This cannot be called development. The revival of degraded regions should be based on people remaining in the area and being able to have decent livelihoods. Participation of all stakeholders in sustainable land management and decision making can make it possible.

Paper presents demographic trends and influence of anthropogenic factor on the state of erosion processes in the area of Grdelicka Gorge.

Key words: agrarian pressure, erosion, migrations, sustainability

INTRODUCTION The main cause of soil loss in the world is poor soil husbandry. In Serbia, the main factor in provoking soil erosion are human activities. The hilly and mountainous regions of Serbia is predisposed to accelerated erosion. About 70 % of its area is steeply sloping. The basic demographic-economic problem of Serbia is the relationship between the size of the agricultural population and the area of soil at their disposal for agricultural production. METHODS OF RESEARCH The representative watersheds selected for study are: Repinska reka, Kalimanska reka and Lještarska dolina.The current status by these watersheds is compared with their condition of five decades ago, when high agricultural pressure was present. The method of Gavrilovic has been utilized for estimation the degree of erosion. The impact of socio-economic factors upon the state of the erosion in the study areas was examined by the statistics data refered to the examined watersheds. These data were supplemented by The Archives of Serbia and Statistical office of the Republic of Serbia.The statistics data obtains necessary informations about the household, number of inhabitans, their sex, age and economic structures, thereafter about those moving in and away, their business outside the household, the state of the livestock funds etc. RESULTS OF RESEARH Regarding the development of erosion in the examined area, these processes can be divided into two periods: up to mid fifties and sixties of 20th century, the period of greatest agrarian overpopulation when erosion was accelerating, and after the mid-fifties and sixties until now, when erosion was decelerating. The Period up to mid-fifties and sixties of 20th century

This period was characterized by a continuous increase in population and household numbers (Tables 1 and 2). One general trend was a relatively great increase in the number of households, compared to the number of inhabitants, enacted mostly by division of the households.The period is characterized by significant changes in the utilization of the agricultural soils. Throughout the valley, hilly and mountainous regions of the examined watersheds, changes encountered included large increases of the arable, meadow, orchard and vineyard areas at the expense of forest and pasture.

Table 1. Number of inhabitants for selected villages of Grdelicka Gorge, 1900-2002 Number of inhabitants

Region Village 1900 1910 1921 1948 1953 1961 1971 1981 1991 2002

Zebince 285 316 382 420 414 424 380 285 190 121 Kukavica . . . 101 121 118 111 53 42 20

Ostrovica . . . 448 399 384 269 166 106 39

Tegovište 248 297 315 387 381 368 295 257 222 183

Oblička Sena . . . 355 350 330 302 216 115 52

Gornje Jabukovo 262 474 465 650 679 614 571 437 296 154 Donje Jabukovo 425 525 499 673 670 561 466 368 219 152

Dupljane 350 416 308 338 362 482 369 300 210 161

Kunovo 933 1015 951 1099 1124 1044 943 810 662 532

Mazarać . . . 382 375 411 282 261 212 197

Manajle 172 211 197 219 216 242 152 113 78 60

Urvič 126 139 98 144 132 122 119 116 87 71

Repince 222 255 271 279 276 281 412 625 790 972 Bresnica 160 181 174 236 241 249 257 308 372 410

Ribnice . . . 238 241 209 213 238 366 471

Source: The Archives of Serbia (data of 1990-1921); Statistical office of the Republic of Serbia (data of 1948-2002)

Table 2. Number of households for selected villages of Grdelicka Gorge, 1900-2002 Number of households

Region Village 1900 1910 1921 1948 1953 1961 1971 1981 1991 2002

Zebince 62 67 70 72 72 77 75 76 70 57 Kukavica . . . 20 22 20 19 16 17 10

Ostrovica . . . 81 74 74 67 49 44 25

Tegovište 49 52 57 65 68 72 73 73 67 66

Oblička Sena . . . 50 49 55 56 54 43 27

Gornje Jabukovo 44 68 83 106 110 112 116 106 99 78 Donje Jabukovo 59 72 76 106 112 108 114 100 81 60

Dupljane 61 72 58 67 64 139 86 85 74 68

Kunovo 133 147 162 194 197 210 211 207 186 165

Mazarać . . . 62 67 130 70 77 70 74

Manajle 28 32 34 42 42 72 42 38 30 27

Urvič 18 23 20 20 22 26 27 28 27 23

Repince 35 36 42 46 50 59 103 168 216 293 Bresnica 32 36 34 47 46 52 66 67 109 123

Ribnice . . . 37 35 39 42 57 92 130

Source: The Archives of Serbia (data of 1990-1921); Statistical office of the Republic of Serbia (data of 1948-2002)

When these changes are observed in parallel with the change in the number of agricultural households and population, the increase in arable and meadow areas in all the three regions is found to be several times higher than the increase of number of households and inhabitants.

As regards livestock, until the mid- fifties, increases were recorded, resulting in increased grazing pressure on the land during the largest agrarian overpopulation. The arable areas and meadows increased by several times over the period between 1895 and 1955 at the expense of forests and steeplands, which were converted for ploughing. Add to this the increase in cattle, sheep and goats, it is clear that such trends had to be reflected in soil erosion. Traditional cattle husbandry here was based upon free grazing in the forests, weak meadows and pastures. Uncontrolled grazing by cattle and goats massively degraded the forests. Following this perturbation of the environmental balance, accelerated erosion stepped up. In all three examined watersheds (Table 3), strong erosion prevailed during high agrarian pressure, and soil removal amounted from to 608 m3·km-2·year-1 (Kalimanska river), 518 m3·km-2·year-1 (Repinska river) and 696,3 m3·km-2·year-1 (Ljestarska valley).

Table 3. State of erosion and soil loss in the researched watersheds

State of Erosion (coefficient Z) Soil Loss (m3 . km-2 .year-1) Y E A R

Watershed

1955 1991 1955 1991 Kalimanska river 1.25 0.36 608 89.30 Repinska river 0.90 0.37 518 50.80 Ljestarska valley 1.10 0.52 696.3 280.20

Source: Original

Period after the mid-fifties of 20th century

During this period, the region was characterized by population migration (Graphic 1, 2 and 3) and changes in the structure of agricultural production. The three factors were significant in bringing about migration: (1) the first was farm incomes, which in this hilly-mountainous region were very low; (2) the second was poor infrastructure; the region is being abandoned. Housing surface areas per capita are small, road connections are weak, especially in the mountainous region, (3) the third and most important factor were the changed socio-economic relations in the country. This resulted in an explosive emigration of the population from this hilly-mountainous region to nearby towns and villages in the valley region. This “down-climbing”, descending into lower regions, was a

response to the better conditions for agricultural production, and because of better access to the market due thanks to a more developed road network.

Another category of migrants is represented by those working outside the household. Out of the labour-active members of the interviewed households, 31.2 % work outside the household, either part-time (seasonally) or permanently, 8.7 % of the workforce is engaged in the education system. Thus, about 40 % of the workforce is either being educated or working outside the household.

Accordingly, the high pressure on the land descreased, primarily due to migrations. The reduction of the population did not result from natural causes or because the natural population increment in this region is small. Graphic 1. Migration balance of population for the villages of mountainous region, 1971-2002.

Source: Statistical office of the Republic of Serbia

Migration balance of the mountainous region of the investigated area was positive only in the Ostrovica village in the period 1971-1990. In the period 1991-2002 migration balance was negative in all villages of mountainous region. In period 1971-1980 average migration balance was -47,4, in the 1981-1991 it was -59,8 and in the 1991-2002 it was -29,6.

Graphic 2. Migration balance of population for the villages of hilly region, 1971-2002.

One village with positive migration balance in 1991-2002 is Mazarać. In all other villages in the researched time, migration balance was negative. In period 1971-1980 average migration balance was -95,1, in the 1981-1991 it was -56,6 and in the 1991-2002 it was -29,9.

Graphic 3. Migration balance of population for the villages of valley region, 1971-2002.

Opposite to the villages of mountainous and hilly region, in the all villages of valley region migration saldo was positive in researched period. In period 1971-1980 average migration balance was 82,7, in the 1981-1991 it was 70,3 and in the 1991-2002 it was 84,7.

Similarly, the number of cattle in the region has declined (Table 4). In all three regions it is evident decline of beeves as well as decline in swines which made bad life conditions in the economic point of view.

Table 4. Livestock fund for selected villages of Grdelicka Gorge, 1981-2002.

Livestock fund beeves swines poultry Region Village

1981 1991 2002 1981 1991 2002 1981 1991 2002

Zebince 260 194 87 212 209 140 308 951 801 Kukavica 61 65 20 36 37 10 8 209 133

Ostrovica 153 137 25 73 173 7 372 492 798

Tegovište 126 84 60 75 77 66 15 793 574

Oblička Sena 199 172 70 129 48 19 433 631 508

Gornje Jabukovo 325 269 137 248 266 100 271 1295 1170Donje Jabukovo 226 139 77 177 114 71 52 827 681

Dupljane 145 121 78 69 90 62 9 721 601

Kunovo 505 388 242 392 358 233 148 2105 2029

Mazarać 159 82 57 139 50 46 108 634 419

Manajle 82 46 21 34 50 25 0 396 304

Urvič 62 56 29 60 76 42 4 272 241

Repince 112 70 47 91 101 69 4 898 949 Bresnica 115 96 54 74 116 84 0 712 973

Ribnice 90 74 42 167 96 57 403 754 881

It is evident the drastic reduction of numbers of sheep and goats (Graphic 4). It has been influenced also by administrative measures: prohibition of goat raising, prohibition of trimming young leafy branches for winter cattle fodder, etc.

Graphic 4. Livestock fund – Number of sheep and goats for researched area, 1981-2002.

Total number of sheep and goats in 1981 was 1973, in 1991 was 656, and in 2002 was 134. The number of sheep and goats was reduced in researched period as following: in mountainous region was reduced from 974 to 58, in hilly region from 486 to 12, and in valley region from 407 to 64. So, total number of sheep and goats in villages of all regions of investigated area had decreased for 93,2% in researched period.

The reduction of the agrarian pressure, as well as numerous biological engineering and administrative measures, contributed to a decrease in the intensity of erosion in the region. Where once strong erosion prevailed in all the three examined watersheds, now weak erosion prevails in Kalimanska and Repinska reka, and moderate in Ljestarska dolina.

The soil removal is reduced from 608 m3·km-2·year-1, 518 m3·km-2·year-1 and 693 m3·km-2·year-1 to amounts ranging to 89.3 m3·km-2·year-1, 50.8 m3·km-2·year-1 and 280.2 m3·km-2·year-1in the researched watershed, respectively (Table 3). Socio-economic prospects

Socio-economic changes over last decades favoured the reduction of the erosion processes. The high agrarian pressure was reduced primarily by emigration. As people moved out, elderly households remained – as a result many arable fields fell from cultivation, becoming weedy or reconverted into pastures. In the graphics 5,6 and 7 are presented average age of inhabitants trough the mountainous, hilly and valley region.

Graphic 5. Average age of inhabitants for the villages of mountainous region, 1981-2002.

Source: Statistical office of the Republic of Serbia Average age of population in mountainous region in the period 1981-1991 had increased from 40,6 to 41 (for 0,99%). There is a significant increase of population average age in 2002. Average age of population in 2002 (60,4) is 47,3% higher than in 1991 or 48,8% higher than in 1981. Compared to

population average age of Serbia (40,3), the average ages in the mountainous area of Grdelicka klisura and Vranjska kotlina is 49,9% higher.

Graphic 6. Average age of inhabitants for the villages of hilly region, 1981-2002.

In hilly region population average age had continually increased as following: 39 in 1981, 44,1 in 1991 and 50,9 in 2002. It means that population average age in 1991 increased for 13,1% compared to 1981 and for 15,4% in 2002 compared to 1991. Population average age in hilly region in 2002 is 18,7% less than in the mountainous region, and for 26,3% higher than population average age on all Serbian theritory.

Graphic 7. Average age of inhabitants for the villages of vallley region, 1981-2002.

In valley region, the average age of population in 1981 and 1991 was 35,0, and in 2002 was 36,5. One can conclude that the same average age was 1981 and 1991 and it increased for 4,3% in 2002. The average age of population in the valley region is 9,4% less than AAP in Serbia in 2002.

There are differences in the number of labour-active inhabitants (LAI) through the period 1981-2002. It is evident decrease of LAI in the villages of mountainous and hilly region. Contrary to this situation, LAI of the villages in vallley region increased in researched period (Graphics 8, 9 and 10).

Graphic 8. Number of labour-active inhabitants for the villages of mountainous region, 1981-2002.

In the mountainous region there were 677 labour-active inhabitants in 1981, 433 in 1991 and 176 in 2002. The conclusion is that the number of labour-active inhabitants had decreased for 36% in 1981-1991, and for 59,4% in 1991-2002.

Graphic 9. Number of labour-active inhabitants for the villages of hilly region, 1981-2002.

In hilly region there were 1431 labour-active inhabitants in 1981, 1020 in 1991, and 414 in 2002. One can conclude that the number of labour-active inhabitants had decreased for 28,7% during 1981-1991, and for 59,4 during 1991-2002. Total number of labour-active inhabitants in the hilly region in 2002 was 2,35 times higher than in the mountainous region.

Graphic 10. Number of labour-active inhabitants for the villages of valley region, 1981-2002.

Opposite to the villages of mountainous and hilly region, in the villages of valley region the total number of labour-active inhabitants was continually increasing during the observed time as following: 584 in 1981, 796 in 1991 and 890 in 2002. One can conclude that total number of labour-active inhabitants increased for 36,3% in the period 1981-1991 and for 11,8% in the period 1991-2002. The valley region of investigated area had 2,15 times more labour-active inhabitants than hilly region and 5,1 times more than mountainous region of the same area in 2002.

Table 3. Number of active agricultural inhabitants in selected villages of Grdelicka Gorge, 1981-2002.

Active agricultural inhabitants

1981 1991 2002 Region Village

all female all female all female

Zebince 168 95 50 14 31 18

Kukavica 28 15 17 7 2 0

Ostrovica 101 62 45 28 13 6

Tegovište 79 70 10 4 9 4

Oblička Sena 135 70 92 43 41 20

Gornje Jabukovo 167 98 124 86 19 10

Donje Jabukovo 121 76 90 55 14 6

Dupljane 77 68 0 0 0 0

Kunovo 421 280 77 37 14 5

Mazarać 102 73 63 50 13 2

Manajle 41 39 22 19 0 0

Urvič 28 25 2 0 2 0

Repince 89 67 7 3 14 6

Bresnica 75 45 44 20 43 19

Ribnice 50 35 20 3 19 9

CONCLUSIONS The natural conditions in the hilly – mountainous region of Serbia favour erosion processes. However, the main factors of accelerated erosion are anthropogenic. The period up to mid –fifties and sixties was characterized by high agrarian pressure and, its consequence, accelerated erosion. The period after mid – fifties and sixties has been characterized by rural depopulation and changes in the structure of agricultural production. As people have left their households, only elderly people remained and many arable fields fell from cultivation. These circumstances, together with biological and engineering measures, contributed to the reduction of the erosion, but it can not be called development.

Beyond any doubt, further development of these regions must be based upon the people remaining in them. This can be assisted by road construction, better connection of the distant villages with the local markets, and better soil management (Zlatić, 1994). It is in this manner that the conservation of natural resources and environmental value will be supported, while enabling people to stay and survive in these regions. REFERENCES Zlatic M. (1994): Evaluation of Erosion Control Works from the Aspect of Technical and Economic Justification on the Endangered Region of Belgrade. Doctoral Disertation, Faculty of Forestry, Belgrade, pp. 250

Zlatić, M., Dragović, N., (1998): Demographic-Economic Aspects of Erosion Processes and Sustainable Soil Management in Hilly-Mountainous Regions, Serbia, Section F: Sustainable Headwater Management, Proceedings of Headwater ’98, The Fourth International Conference on Headwater Control, Merano, Italy, Editors: Martin J. Haigh, Josef Krecek, G. S. Rajwar, Mariane P. Kilmartin; A.A. Balkema/Roterdam/Brookfield, pp. 391-398

Influence of Human Activities and Demographic Trends on the Environment of Grdelicka Gorge (South...

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