CONTENTS
H. Najdenski
3-4
I. MAN
AND BIOSPHERE
Possibilities and
limitations on the use of carbon dioxide in
the industry
S.
Turmanova, G.
Peeva
5-10
Green rocket engines for
civil purposes
N.
Siveva, K.
Krumov, G.
Krumov, S.
Venkova, H.
Skandaliev
11-16
A.
Sotirov, D.
Malwood, N.
Pistalov, S.
Savova, N.
Siveva, H.
Skandaliev, T.
Skandaliev, V.
Sotirov, K.
Sotirov
17-24
Fundamental ideas on
ecology and biophysics development
I.
Christov 25-29
II. FOREST
BIOLOGY
Natural disasters in Bulgarian forests
A.
Alexandrov, Z.
Bakalov 30-34
Soil
assessment of gray forest soils in Northwest Bulgaria
S. Bogdanov
35-43
Forest fires in
Bulgaria for the 2009-2018 decade
H.
Tsakov, A.
Alexandrov, O.
Roeva, D.
Zoteva
44-49
III. ECOLOGICAL AND SUSTAINABLE AGRICULTURE
Assessment of
biochar and vermicompost
and effect of
compost
mixtures
S. Marinova, N.
Kathijotes, E.
Zlatareva
50-57
Determination of
economically feasible thickness
of the reed
roof of
building for laying hens
V.
Dimova, D. Georgiev 58-64
M.
Mladenov
65-71
IV. SCIENTIFIC
FORUMS
16th World
conference on
anaerobic biodegradation
23-29
June
2019., Delft, The
Netherlands
72-75
In Memoriam
Assoc. Prof. Dencho
Denchev (1940 – 2019)
76
POSSIBILITIES AND
LIMITATIONS ON THE USE OF CARBON
DIOXIDE IN THE INDUSTRY
Sevdalina
Turmanova, Gergana Peeva
Abstract: The carbon dioxide is a
greenhouse gas causing. It absorbs heat causing raising of
Earth average
temperature. In
2003, the European Parliament and the Council of the EU
identified climate
change as a priority area of action.
On
the other hand, carbon dioxide has been used in industry for
over a century.
Carbon dioxide can be used and used in two main ways:
through biological and
chemical transformation (the production of synthetic and
designer fuels,
polymers, plastics, organic chemistry) and direct use (the
production of food,
oils).
The
main strategies for reducing of carbon dioxide emissions
aiming capture and storage of
CO2. Bulgaria is
also
implementing measures to reduce carbon dioxide emissions.
Neli Siveva, Kalin
Krumov, Goro Krumov, Silvia Venkova, Hristofor Skandaliev
Abstract: A substantial need for
replacement
of the currently used construction materials of the latest
generation aircraft
based on polymers and composites of petroleum products is existed. The aim of the study is
fire tests in a real working environment of a new generation
of environmentally
friendly solid rocket
propellant engines,
completely degradable in the
nature.
Test results including internal engine ballistics and
thermo-mechanical
characteristics of composite materials after burning of rocket fuel are
presented.
Anton Sotirov, Dana
Malwood, Nikola Pistalov, Siana
Savova, Neli Siveva, Hristofor Skandaliev,
Tomislav Skandaliev, Viktor
Sotirov, Krasimir Sotirov
Abstract. It
is suggested that despite the small population in the
region, the pressure on
the river ecosystem by the local population is very
strong. The biggest
ecological problem of the river is the non-observance of
environmental
standards by the local population. According to
unpublished data, number of
natural and legal persons carrying out gold mining, and
with non-organic
methods and means – using of mercury amalgam for extraction
of gold on site, prospecting, extraction, enrichment
without approved projects
and without recultivation of the terrain,
etc. The region is rich in minerals and in their search,
exploration and
extraction there is nothing wrong, as long as it is legal,
in compliance with
environmental norms, on a scientific basis.
Key words: environment,
Dragovishtitsa river, mining activities
FUNDAMENTAL
IDEAS ON ECOLOGY AND BIOPHYSICS DEVELOPMENT
Ilia Christov
Abstract. The paper deals with a
surveys on the historical development of
basic ideas on the emergence and separation the scientific
knowledge in
physics, biology, chemistry, ecology, etc. The general
structure of biophysics
is presented. The significance of methodology and
achievements in biophysics
for solving the global and regional problems of ecology are
emphasised.
NATURAL DISASTERS IN BULGARIAN
FORESTS
Abstract: The natural hazards
include cosmic, geological,
water, fire, meteorological and health disasters. Some
data about them though
partial exist as far back as ancient times, while they
were described more
detailed and precisely during XIX and XX century and
particularly in the last
decades. From meteorological disasters in Bulgarian
forests badly distractive
are windfalls and tornado. A windfall at Rila monastery
forests in the year
1893 affected 4,000 dka with growing stock of about
200,000 m3 and over again in 2011 uprooted some
thousand beech trees. A tornado in
1961 destroyed valuable coniferous forests in the Western
Rhodopes in a strip
with length of approximately 40 km and width to 1 km
spreading all over a
territory of 28,000 dka as trees with growing stock of 1
million m3 were rooted out and broken off. A
tornado at Vitosha Mt. in 1956
affected 2,000 dka while 750 dka of Norway spruce stands
were fallen down in
2001. The most damages over forest ecosystems however
cause fires. Particularly
affected by fires were forests in the Rila-Rhodope massif.
They were set on
fire by shifting livestock-breeding in order to open new
grazing grounds. The
forest fire statistics in the country during XX century
presents some peaks
(burned down 270,000 dka in 1903 and 172,640 dka in 1993)
but at the beginning
of XXI century is observed
a sharp increasing of forest
areas destroyed by fire: 574,000 dka (2000), 201,500
dka (2001), 430,000 dka (2007) and 127,300 dka
(2012). The next in turn disasters in Bulgarian forests
are result of
withering, pest attacks and diseases. The diseases and
drying of forest
plantations and stands in recent years are increasing,
reaching 247,531 dka
during the year 2017 while damages from beetle calamities
affect 174,049 dka.
Methods for management of forests in order to reduce the
natural hazards are
investigated and recommended.
Key words: windfalls, tornado,
forest fires, calamities,
torrents.
SOIL
ASSESSMENT OF GRAY FOREST SOILS IN NORTHWEST BULGARIA
Simeon
Bogdanov
Abstract.
Soil assessment is important for environmentally friendly
use of forest
resources and their sustainable development. It provides a
basis for
optimization of forest stand composition in order to
effective use of soil
fertility and maximum economic effect in the forestry
activities. The paper
presents results from experience to soil assessment on Gray
Forest soils (Gray
Luvisols) in Northwest Bulgaria. The soils are situated in
the Lower forest
vegetation zone (0 – 600 m a.s.l.) of the Misian forest
vegetation area. Soil
assessment is consisted on differentiation of researched
soils according to
their silvicultural properties. They are determined on the
base of soil depth,
content of humus, total N, and soil available water. The
bonitet of stands and
the composition of tree species have been analyzed as
indicators of the soil
silvicultural effect. Conformity between soil silvicultural
properties and soil
silvicultural effect has been established.
Key
words: gray forest
soil, soil assessment, soil silvicultural properties, forest
stands.
Hristo Tsakov,
Alexander Alexandrov, Olympia Roeva,
Dafina Zoteva
Abstract: Forest
fires annually affect large areas in Bulgaria, cause
changes in forest
ecosystems and cause unpredictable environmental
consequences. At the
same time, forest
fires are one of the biggest pollutants of the
environment. After the burning
of the plant organics, the structure, nutrient and humus
stock of the soil are
changed. Water run-off changes, microclimate and
business conditions
deteriorate.
For
2009-2018, 4366 forest fires
occurred and 493480 decares of forests were destroyed.
Frequently repeated
drought periods in the last decade (2009-2018) have led
to an increase in the
number of forests fires, a reduction in species
diversity, as well as the
natural restoration of the burnt areas.
In 2018,
222 fires were recorded in
forests. In the autumn season, forests fires were 139.
There is a new moment of
increase of the fires at the beginning of winter, as
well as a year-round
change of the fire activity with two maximums: in the
spring – February, March
and mid April, and in the summer – in July, August and
September.
The article
discusses issues related
to the dynamics, seasonal distribution, burnt areas by
type of property, the
causes of the occurrence and the material damage caused
by the forest fires for
the decade 2009-2018. The analysis of the fire situation
in Bulgaria is based
on the data published in the annual reports of the
Executive Forest Agency by
regional directorates in chapter “Forest protection from
fires” (2009-2018).
Svetla Marinova, Nicholas
Kathijotes, Elena Zlatareva
Summary. There are natural
products that are
add to the soil to
stimulate the growth of plants. These are biochar and vermicompost. The
low
content of the basic
macronutrients in
biochar
requires composting with
nutrient - rich materials such as
vermicompost, manure, sludge, mineral fertilizers, etc. The
aim of the study is
to evaluate vermicompost
and biochar and to prepare compost
variants
with the participation of individual
products in different proportions depending on their
qualities. To determine
their effect as soil improvers in pot experiments. The values
of essentially
biogenic elements are
higher in vermicompost, while in biochar they are significantly
lower.
The studied heavy
metals are below the MAC.
Three compost
mixtures were prepared with different participation of the
two starting
products, depending on
their properties and their effect in growing experiments
on 2 soils with
indicator lettuce culture was
established. The yield of the various compost mixtures shows
that regardless of
the
soil on which
the lettuce is
grown, the best yield is obtained with the mixture with equal
percentages
of vermicompost and biochar.
The chemical characteristics
of the lettuce
plant production show that
as the rate if mixtures
increases, the basic
macronutrients and trace elements
increase. The
highest values of the N, P and K elements
in lettuce are observed at
50% vermicompost:
50% biochar
on both soils.
V. Dimova, D. Georgiev
Abstract: The aim of the recent study is to evaluate the
economically feasible thickness
of the roof of laying hens building using thermal
insulation from
reed and different
fuel
for heating (pellets and Donbass coal). To achieve this, six variants of
10-, 15-, 20-, 25-, 30- and
35-cm-thick roof reed
plates have been
developed. The price of a reed plate is calculated and
includes only the
construction work for its workpiece. The construction value of the
finished roof (incl. VAT and transport) was obtained by
adding to the value of
the workpiece the value of the construction works on the
site, the labor cost,
the performance of the wooden siding, the waterproofing
and the slats. The
presented methodology determines the annual energy losses
per 1 m2
of the roof construction. The cited annual costs for
thermal insulation are
calculated as the sum of the annual energy costs and
depreciation charges. The
condensation of water vapor on the inner surface of the
reed roof was checked.
The results obtained show that the most appropriate
thickness of thermal
insulation is 25 cm when using fuel pellets and 30 cm when
using Donbass coal.
All the variants of the reed roof under study meet the
hygiene requirements for
preventing condensation of water vapor on its inner
surface.
Keywords: Reeds roofs of buildings, laying hens,
pellets, coals, energy
losses, annual costs
OBSERVATIONS
ON
CHANGES IN THE PARAMETERS OF THE “HOME” COMPOSTING PROCESS. PART 1 -
PHYSICAL PARAMETERS
Metodi K. Mladenov
Key
words: composting; physical
parameters;