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Науковий в!сн и к НЛТУУкраТни Scientific Bulletin of UNFU http://nv.nltu.edu.ua https://doi.org/10.15421/40280101
Article received 24.01.2018 р. Article accepted 28.02.2018 р.
УДК 630*116:582.475:631.62
ISSN 1994-7836 (print) ISSN 2519-2477 (online)
1 EE3 Correspondence author V. Yu. Yukhnovskyi yukhnov@ukr.net
V. Yu. Yukhnovskyi, R. M. Prokopchuk
National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
HYDROLOGICAL REGIME AND GROWTH OF PINE STANDS IN CONDITIONS OF DRAINAGE RECLAMATION SYSTEMS
A retrospective analysis of the formation and development of drainage reclamation in Volyn Polissya was carried out. The growth of pine plantations within the controlled drainage system and under the control was simulated. The data of samples and materials of the database of plantations growing on drained and control plots were used for modelling of height dynamics and changes in stocks with age. Dynamics of heights and stocks are described by the models of the polynomials of the second degree and the exponent equations. It was established that by the middle of the 3rd age class, the height of plantations on drained areas exceeds the height of plantations under the control of 2.1 m. Starting from the 3rd age class, pine stands on drained areas sharply increase the growth and at the age of quantitative ripeness, the difference in heights reached 3.0 m. Pine plantations in land reclamation areas pass into the upper class of productivity. The difference between the average heights in the 5th age class is 2.7 m. The effect of drainage is traced after 30 years, when the root system penetrates deeper horizons. The growth of roots on the control sites close to the surface of the water table is inhibited. At the same time, the soil saturated with oxygen stimulates the growth processes of the wood plants between the drainage channels, which lead to an increase in the productivity of the plantings. Comparative analyses of changes in planting stock shows that in the fourth age class the stock of pine stands on drained areas exceeds 15 %, and at the age of quantitative maturation this difference reaches 21 %, which makes 89 m3-ha-1 and is a significant argument for the use of drainage reclamation in the wetlands of Volyn Polissya. The analysis of the hydrological regime of the drainage system "Strashevo" for the 14-year period showed that the water table during 2010-2017 sharply decreased reaching a stable value of 124-140 cm, whereas by 2009 it had fluctuated within the limits of 61-83 cm. The prolonged and significant decrease in water table leads to the declining of plantations, therefore, to ensure optimal hydrological regime of forest areas it is necessary to sluice channels or reconstruction of the drainage system in the system of bilateral action.
Keywords: reclamation; drainage channels; water table; pine stands; productivity; height.
Introduction. Free encyclopaedia interprets the hydro-logical regime as a natural change in the hydrological elements of the water object in time, due to physical, geographical and, primarily, climatic conditions of the basin (Free Encyclopedia, n.d.). Hydrological regime includes perennials (years with increased or lowered water content), annual or seasonal (flood, middle of summer, inundate) and daily fluctuations of water level of a water object. The hydrological regime of rivers, lakes, reservoirs, and wetlands is distinguished depending on the type of water object.
The natural hydrological regime often changes substantially under the influence of human economic activity. The use of drainage reclamation has the greatest impact on the hydrological regime of wetlands, because it radically changes the water-air regime of the roots-saturated soil layer over a long period of time. Therefore, the study of changes in the hydrological regime in time is necessary to find out the growth processes of wood species, increase the biologi-
cal stability and productivity of forest stands.
Most scientists (Kostyakov, 1925; Tyulenev, 1926; Pro-kopowicz, 1926 et al.) explain the positive effect of drainage reclamation by the fact that during the drainage process root systems are released from excessive soil moisture, thereby increasing the area of plant nutrition. The Chief of the Western Expedition on the drainage of wetlands J. I. Zhi-linsky believed that drainage is a positive factor, since water from the marshes will flow to the rivers rather than evaporate (Zhilinsky, 1899). The point of view of I. I. Zhi-linsky was supported by a prominent hydrologist and clima-tologist E. V. Oppokov, who proved the absence of a year between drainage and wateriness of the rivers on the basis of conducting many years of observation (Dokuchayev, 1876).
However, the founder of soil science V. V. Dokuchaev adhered to other views. He believed that the bogs in Polissya were the main source of river filling, and their draina-
1нформащя про aBTopiB:
Юхновський Василь Юршович, д-р с.-г. наук, професор, завщувач кафедри люовоТ мелюрацп i опти1^зацп люоаграрних
ландшаф^в. Email: yukhnov@ukr.net, yukhnov@nubip.edu.ua Прокопчук Роман Миколайович, астрант кафедри люовоТ мелюрацп i опти1^зацп люоаграрних ландшаф^в. Email: lisromeo90@gmail.com
Цитування за ДСТУ: Yukhnovskyi V. Yu., Prokopchuk R. M. Hydrological Regime and Growth of Pine Stands in Conditions of Drainage
Reclamation Systems. Науковий вюник НЛТУ Укра'ши. 2018, т. 28, № 1. С. 9-13. Citation APA: Yukhnovskyi, V. Yu., & Prokopchuk, R. M. (2018). Hydrological Regime and Growth of Pine Stands in Conditions of Drainage Reclamation Systems. Scientific Bulletin of UNFU, 28(1), 9-13. https://doi.org/10.15421/40280101
ge would lead to the shallowing of rivers and their streams (Oppokov, 1909).
Reclamation works on the drainage of Volyn Polissya began to take place in the pre-revolutionary period. The first drainage channels began to run in Polissya and in separate areas of the Carpathian and Transcarpathian regions. During the work of the Western Expedition on the drainage of the Volyn marshes (1873-1898), the Zamyslovtsy Canal was constructed. It allowed the drainage of about 10,000 hectares of wetlands (Tolstoy, 1990; Kuksin, 1991).
During the period of 1899-1908, the land reclamation works on drainage was carried out in insignificant amounts, and since 1909 the land reclamation works on drainage began to be given more attention. Land reclamation was carried out by zemstvo and land management commissions. In the pre-revolutionary period, reclamation works were carried out on an area of 454 thousand hectares (Shainin, 1990; Bozhok, 1976).
Beginning from the second half of the twentieth century the drying reclamation in the area of the enterprise was carried out on large volumes on the area of 10,000 ha of forest plots. The deployment of drainage works in the 60th of the last century required the development of a scientific basis for drainage. In 1965 a collection was published devoted to the drainage and development of bogs in the Polissya zone of Ukraine. One of these publications, which covered the history of the Sarny Research Station, was the work of I. O. Khmara (1965). The history of drainage of the lands of the Zhytomyr region has published a significant volume by the article P. T. Bozhok (1976). On multi-year statistical material, the author analyzed the dynamics of drainage works, distinguishing their periods of activation and collapse. Only ten years (1966-1976) in the Rivne region, drainage systems were constructed and reconstructed on an area of 169.000 hectares. Subsequently, the land reclamation works were carried out in larger volumes and to date, the area of drained lands has been brought to 374.400 hectares, which is 11 % of the land reclamation fund of the region.
The problems of environmental change in Polissya related to drainage works are devoted to the works of N. I. Tyulenev (1926), V. E. Alekseevsky, Yu. I. Bakhmachuk (1992) et al.
Since the beginning of large-scale forest-reclamation works more than half a century has passed, and in the past 15-25 years almost no works on the care and operation of drainage systems has been carried out, which has led to the re-watering of previously drained lands (Alekseyevsky, & Bakhmachuk, 1992).
According to (Ustskiy, Mykhailychenko, & Rum-yantsev, 2016), the results of studying changes in the hydrological regime on the condition of forest plantations are ambiguous. The research of forest ecosystems state has shown that after drainage reclamation in wet types of forest vegetation, the moisture level is reduced, while the trophi-city increases by 1-2 units of the scale of the Alekseev-Pogrebnyak edatic grid (Ustskiy, Mykhailychenko, & Rum-yantsev, 2016). At the same time, no significant changes were observed in very wet pine forests on the poor and podzol soils.
The purpose of the research is to trace the changes in the hydrological regime of reclamation forest areas during the reconstruction of the drainage system, to determine the causes of a sharp fluctuation of groundwater levels, to determine the impact of drainage on the state and productivity of pine plantations in the conditions of Volyn Polissya.
Material and methods of research. The research was carried out in pine stands of the II-VII classes of the age, which grow on the drainage reclamation system "Strasho-vo" of the State Enterprise "Sarny Forestry" of Volyn Regional Forestry.
State Enterprise is located in the central part of Volyn Polissya. Vegetation period is 156 days; average annual rainfall is 624 mm. Climatic factors that negatively affect the growth and development of forest vegetation include early autumn and late spring frost. The predominant types of soils are soddy-podzolic, sandy and clay-sandy varieties; along the lowland there are peat-gley soils, which have a peat layer on the surface.
The predominant forest type in the Sarny Forestry is the moist pine site, which covers an area of 10428.5 hectares (24.5 %) of forest lands, then fresh pine forest -6129.3 hectares (14.4 %) and fresh pine completed site -5274.2 ha (12.4 %). Dry pine sites are occupied 2799.9 hectares (6.6 %).
By degree of humidity, most of the soils refer to raw -35.8 % and moist - 30.5 %. The share of lands with excessive humidity accounts for 26.9 % of the area covered with forest vegetation. The swamps cover an area of 1433.2 hectares. The territory of the Sarny Forestry is located in the Sluch and Goryn river basin.
The area of the lands of the forestry fund of the state enterprise "Sarny Forestry" is 49561 hectares, of which 73.6 % are exploitation forests. The coniferous species occupy an area of 31040.9 ha (72.9 %), hardwood - 1383.7 ha (3.3 %), softwood - 10126.8 ha (23.8). The predominant species is pine (Pinus silvestris L.), which covers an area of 30,762.9 hectares (72.3 %). The distribution of the main forest species in the age groups is not optimal. Thus, young plantations make up 21.1 %, middle-aged stands - 61.7 %, pre-mature plantings - 7.9 %, mature and over mature stands - 9.3 % of forest covered area.
Control objects were chosen far beyond the dehumidifi-ers, where the plantings were not exposed to drainage reclamation. To investigate the effect of drainage on the growth and development of pine stands in drained areas, hydrologi-cal transects were laid within them, wells were laid for measuring the level of ground water table during the growing season, and 14 temporary samples were laid down according to the generally accepted methods of forest measurement (Yaschenko, Korus & Turich, 2006).
Results and discutions. Creation of drainage systems has led to an increase in arable land in the region, and the reclamation of the forest stands directly linked to drainage systems on agricultural land. The main water intakes in the area of the enterprise are the Sluch and Goryn rivers, then the Pripiat and the Dnieper. Selected plantations are close in composition, grow in similar forest plant sites (wet and fresh pine sites) and differ in the biometric indices and sanitary conditions (Table 1).
Data Table 1 indicates a significant effect of drainage on the growth and productivity of pine plantations. For the sake of visualization, simulation of heights dynamics and changes in stock of plantations with age was developed. For simulation of heights, the data of test areas and materials of the database of plantations that grow on drained and outside the territory were used. Dynamics of heights of pine plantations growing within the drainage system and on the control are described respectively by the model of the polynomial of the second degree (1) and the exponent equation (2).
Number of samples Stand ■ ■ composition ; Variant of experience Age, years Average Site index Density Stock, m^ha"1 Stock of density 1.0, m3-ha-1
D, cm H, m dry part growing trees
1 7Ps3Bp Experience 29 12,4 12,9 I 0,85 15 186 236
2 7Ps1Q2Bp Control 25 9,1 9,6 I 0,71 20 121 199
3 7Ps3Bp Experience 31 13,3 13,4 I 0,68 20 122 209
4 8Ps2Bp Control 35 14,8 12,1 II 0,79 10 159 214
5 10Ps+Bp Experience 48 20,2 18,5 I 0,74 35 252 388
6 8Ps2Bp Control 49 17,6 17,4 II 0,65 10 214 345
7 8Ps2Bp Experience 57 24,2 22,8 Ia 0,7 25 308 476
8 10Ps+Bp Control 57 19,1 20,3 I 0,65 15 264 429
9 8Ps2Bp+Pt Experience 64 27,5 28,3 Ib 0,71 20 403 596
10 8C32En+Oc Control 63 26,1 24,4 Ia 0,72 30 286 439
11 10Ps+Bp Experience 73 29,5 28,5 Ia 0,64 20 352 581
12 10Ps+Bp Control 72 28,4 26,4 Ia 0,66 15 323 512
Ps - Pine (Pinus sylvestris L.); Bp - Birch (Betulapendula Roth.); Aspen - (Populus tremula L.).
Graphic interpretation of the obtained models is shown in Fig. 1.
y = -0,0011x2 + 0,480x, R2 = 0,975, (1)
y = 0,3702x°'9967, R2 = 0,960, (2)
where x - age of stands, years; v - height, m.
35 30 25
Ë
20
od
o 15 K
10
value of the latter was transferred to the density of normal stands.
2 2 (3)
(4)
where: x - age of stand, years; yi - stock of stands, m3-ha-1.
y1 = -0,058x2 + 14,934x - 175,24, R2 = 0,963, y = 7,9003 x0'9722, R2 = 0,951,
1 • ___ -e
1 • •
• — • -- 0
f1
Ag e, years
700 600 500 ~s 400 ■i 300 ê, 200 100
—«
l
•
Age, years
20
30
40
50
60
70 80
20
30
40
50
60
70
80
Fig. 1. Dynamics of heights of pine forest stands on the drainage system (1) and on the control (2)
Fig. 1 indicates that by the middle of the third age class, the height of plantings on drained areas exceeds the height of plantations at a control of 2.1 m. Starting from the third age class, pine trees on drained areas dramatically increase the growth and at the age of quantitative ripeness the difference in heights reaches 3.0 m. Pine plantations in land reclamation areas pass into the highest site class. The difference between the average heights in the 9th age class is 2.7 m.
The dynamics of changes in the stocks of pine stands growing within the drainage system and on the control characterize respectively models 3 and 4, and their graphical interpretation is depicted in Fig. 2. It should be noted that the researched stands are multiplied, close to the modal ones. Therefore, to obtain the laws of stock build-up, the
Fig. 2. Dynamics of stocks of pine stands on the drainage system (1) and on the control (2)
The effect of drainage can be traced after 30 years, when the root system penetrates deeper horizons. It's inhibited the growth of roots on the control sites close to the surface of the water table. At the same time, the soil, saturated with oxygen, stimulates the growth processes of the tree plants between the drainage channels, which lead to an increase in the productivity of the plantings. Comparative characteristics of changes in planting stock are presented in Table. 2.
In the fourth age class the stock of pine stands on drained areas exceeds 15 %, and in the age of quantitative maturation, this difference reaches 21 %, which makes 89 m3-ha-1 and is a significant argument for the use of drainage reclamation in the wetlands of Volyn Polissya.
Age, years Stock of stands, m^ha"1 The difference in the stock of stands on the drained system and control
on drained areas on control plots m^ha"1 %
20 100 145 -45 -31,0
30 221 216 5 2,3
40 329 285 44 15,5
50 426 354 72 20,4
60 512 423 89 21,0
70 586 491 95 19,2
80 648 560 89 15,9
At the same time, nowadays, there has been a decrease in ground water level throughout the Polissya, which, according to scientists, is one of the reasons for the massive and partial decline of forest stands (Sarny Forestry, 2014).
It was significant changes in the climate in the region for the last two decades. This usually affects the hydrologi-cal regime of forest areas. The data for the period 20042017 on the change in the hydrological regime and water
table of the drainage system "Strashovo" are reflected in the table 3.
The analysis of data (Table 3) shows that the level of water table drops sharply from 2011, reaching a stable value of 124-140 cm. If the water table in 2006 was 61 cm, then in 2016 the average annual water table reached 140 cm. That is, the difference is 79 cm.
Years Water table, cm Average annual water table, cm
IV V VI VII VIII IX X
2004 71 n.d. n.d. n.d. n.d. 94 n.d. 82
2005 62 49 54 74 45 75 87 64
2006 57 66 60 58 58 48 81 61
2007 73 86 81 49 75 88 93 78
2008 51 n.d. n.d. 76 65 34 45 54
2009 61 86 73 83 95 92 90 83
2010 83 99 110 87 115 123 75 99
2011 124 140 145 89 152 151 115 131
2012 160 130 110 114 110 129 n.d. 124
2013 164 137 122 127 146 167 119 140
2014 143 133 131 128 143 120 119 131
2015 145 132 145 129 147 125 128 136
2016 149 139 141 141 138 129 n.d. 140
2017 140 168 142 149 130 129 115 139
Since the water table decreases, which, in turn, leads to the drying of plantations, it is necessary to apply the sluice of drainage channels. A progressive moment is the reconstruction of drainage systems in a two-way system, or the so-called drainage and humidifying systems, which for the intensive growth of plants during the vegetation period provide an optimal hydrological regime of forest areas.
Conclusions. Hydrotechnical melioration is a powerful means of increasing the productivity of forest plantations, since in the beginning of the growing season root plant systems are released from excessive moisture, which leads to an increase in the feeding area of tree species. Since the time of the forest reclamation in Polissya, the productivity of forests has increased on average on the one class of productivity.
The analysis of the hydrological regime of the drainage system "Strashovo" during the 14-year period showed that the water table sharply decreases, reaching a stable value of 124-140 cm for the last 6 years, whereas during 20042009 it varied within 61-83 cm.
Prolonged and significant decrease of water table leads to the drying of plantations, therefore, in order to ensure optimal hydrological regime of forest areas, it is necessary to use sluice of channels or reconstruction of the drainage system in a two-way system.
By modelling the growth of pine plantations it was found that by the middle of the 3rd age class the height of plantations on drained areas exceeds the height of plantations at the control of 2.1 m. Starting from the 3rd age class, pine stands on drained areas dramatically increase the growth and in the age of quantitative ripeness the difference in heights reaches 3.0 m. Pine plantations in land reclamation areas pass into the highest class of productivity. The difference between the average heights in the 9th class of age is 2.7 m.
nepe^iK BHKopHeraHHx g»epe.n
Alekseyevsky, V. (Ed.), & Bakhmachuk, Yu. (1992). Environmental aspects of land reclamation in Volyn. Lutsk - Kiev: Lybid. 235 p.
Bozhok, P. (1976). Development of works on drainage of land in Zhytomyr region. Scientific works of the Ukr. Agr. academy, 173, 3-12.
Dokuchayev, V. (1876). Probable restriction of the rivers of the European plain. In the book. Meeting of the St. Petersburg rural masters, 7. St. Petersburg.
Free Encyclopedia. (n.d.). Wikipedia. Retrieved from: https://uk.wiki-pedia.org/wiki/Пдролоriчний режим.
Khmara, I. (1965). Brief works of the Sarny Research Station on the development of the Marshland of the Polessya zone of the USSR. Kyiv. Harvest, 3-10.
Kostyakov, A. (1925). The prospects of land reclamation in the USSR (European part). Moscow. The publication of the State Planning Committee of the USSR. 269 p.
Kuksin, I. (1991). Polissya research party E. Oppokova. Reclamation and water management, 2, 57-58.
Oppokov, E. (1909). On the Hydrological Role of Marshes. Agriculture and Forestry, 9, 37-57.
Prokopowicz, M. (1926). Meljoracje w Polsce wraz z odnosnem usta-wodawstwem oraz ustawa wodna. Torun. 339 p.
Sarny Forestry. (2014). Project of the organization and development of forestry of the state enterprise "Sarny Forestry". Irpin. Ukrderzhlisproekt. 206 p.
Shainin, L. (1990). Land-reclamation legislation and policy in Russia at the turn of the Х1Х-ХХ centuries. Reclamation and water management, 11, 59-60.
Tolstoy, M. (1990). From the History of the Water Economy of Russia. Reclamation and Water Management, 4, 58-59.
Tyulenev, N. (1926). History of occurrence, tasks, program and the first achievements of Rudnia-Radovelskaya Marsh Experimental Station. Publ. by Korosten land department. Issue I. 65 p.
Ustskiy, M., Mykhailychenko, O., & Rumyantsev, M. (2016). Influence of drainage reclamation on radial growth of pine and oak stands in the conditions of Zhytomyr Polissya. Scientific bulletin of UNFU, 26(4), 142-147. https://doi.org/10.15421/40260422
Yaschenko, P., Korus, M., & Turich, V. (2006). Estimation of the effect of melioration on the change of biometric indices of pine forest stands of Shatskyi National Park. Scientific Bulletin of UNFU, 16(1), 19-26.
Zhilinsky, I. (1899). Essay on the work of the Western Expedition on the drainage of swamps (1873-1898). Kiev Publishing house of the Ministry of Agriculture and State Enterprises. 744 p.
В. Ю. Юхновський, Р. М. Прокопчук
Нацюнальний утверситет бюресурав i природокористування Украши, м. Кшв, Украта
ПДРОЛОГ1ЧНИЙ РЕЖИМ I Р1СТ СОСНОВИХ НАСАДЖЕНЬ В УМОВАХ ОСУШУВАЛЬНИХ МЕЛ1ОРАТИВНИХ СИСТЕМ
Здшснено ретроспективний аналiз становлення i розвитку осушувально! мелюрацп у Волинському Полка. Змодельова-но рют соснових насаджень у межах регульовано! осушувально! системи i на контроле Встановлено, що до середини III кла-су вжу висоти насаджень на осушених дшянках перевищують висоти насаджень на контролi на величину 2,1 м. Починаючи з III класу вжу, сосна на осушених дшянках стрiмко збшьшуе прирют й у вщ кшьюсно! стиглост рiзниця у висотах сягае
3,0 м. Cochobí насадження на мелюративних дiлянках переходять у вищий клас 6oHÍTeTy. Рiзниця мiж середнiми висотами у VII класi вжу становить 2,7 м. Поршняльний аналiз змш запасiв соснових насаджень показуе, що в IV клас в1ку запаси сосни на осушених дшянках перевищують 15 % вiд контролю, а у вщ кшьюсно! стиглоста ця рiзниця сягае 21 %, що становить 89 м3та"' i е вагомим аргументом застосування осушувально1 мелюрацп на надмiрно зволожених землях Волинського Полю-ся. Аналiзуючи пдролопчний режим осушувально1 системи "Страшево" за 14^чний перiод, з'ясовано, що рiвень Грунтових вод упродовж 2010-2017 рр. с^мко знижуеться, сягаючи стабшьно! величини 124-140 см, тодi як до 2009 р. вш змшювався в межах 61-83 см. Тривале i значне пониження рiвня Грунтових вод призводить до всихання насаджень, тому для забезпе-чення оптимального пдролопчного режиму лiсових дшянок потрiбно застосовувати шлюзування каналiв або реконструкцiю осушувально! системи у систему двосторонньо1 дп.
Ключовi слова: мелюращя; осушувальнi канали; ршень Грунтових вод; сосновi насадження; продуктившсть; висота.
В. Ю. Юхновский, Р. Н. Прокопчук
Национальный университет биоресурсов и природопользования Украины, г. Киев, Украина
ГИДРОЛОГИЧЕСКИЙ РЕЖИМ И РОСТ СОСНОВЫХ НАСАЖДЕНИЙ В УСЛОВИЯХ ОСУШИТЕЛЬНЫХ МЕЛИОРАТИВНЫХ СИСТЕМ
Осуществлен ретроспективный анализ становления и развития осушительной мелиорации в Волынском Полесье. Смоделирован рост сосновых насаждений в пределах регулируемой осушительной системы и на контроле. Установлено, что к середине III класса возраста высоты насаждений на осушенных участках превышают высоты насаждений на контроле на величину 2,1 м. Начиная с III класса возраста, сосна на осушенных участках резко увеличивает прирост и в возрасте количественной спелости разница в высотах достигает 3,0 м. Сосновые насаждения на мелиоративных участках переходят в более высокий класс бонитета. Разница между средними высотами в VII классе возраста составляет 2,7 м. Сравнительный анализ изменений запасов сосновых насаждений показывает, что в IV классе возраста запасы сосны на осушенных участках превышают 15 % от контроля, а в возрасте количественной спелости эта разница достигает 21 %, что составляет 89 м3та"' и является весомым аргументом применения осушительной мелиорации на избыточно увлажненных землях Волынского Полесья. Анализируя гидрологический режим осушительной системы "Страшево" за 14-летний период, установлено, что уровень грунтовых вод в течение 2010-2017 гг. резко снижался, достигая стабильной величины 124-140 см, тогда как в 2009 г. он колебался в пределах 61-83 см. Продолжительное и значительное понижение уровня грунтовых вод приводит к усыханию насаждений. Поэтому для обеспечения оптимального гидрологического режима лесных участков необходимо применять шлюзование каналов или реконструкцию осушительной системы в систему двустороннего действия.
Ключевые слова: мелиорация; осушительные каналы; уровень грунтовых вод; сосновые насаждения; производительность; высота.
