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Open access

Ilie Covrig and Mădălina Florina Presecan

Abstract

The research we have undertaken seeks to clarify some aspects concerning the specific characteristics of aforest microclimate. Spot measurements were carried out for 12 hours/day, on certain days that are typical for the period of vegetation and, respectively, for the period of vegetative rest. Measurements regarding the intensity of light were conducted across surfaces where progressive felling had been applied. The research findings about the light regime are presented below: 1. Surfaces subjected to the progressive felling treatment I - seeding fellings that create cut block sites in the mature stand canopy u. a. 74 B, UP III, Nirajul Mic, the Sovata Forestry. In these regeneration areas appear noticeable changes of the light regime, caused by the intensity of the fellings, the size of the cut block sites and the position of each cut block site sector. Thus, in clear cut block sites, having an elliptical shape of 0.5 H3 X 0.75 H*, in which seedlings have not yet been planted, the amount of light that reaches the soil surface, in relation to the open field solar radiation, is approx. ¼ - 1/3 in the eastern and southern sectors, 2/3 in the central sector and, respectively, 2/5 - ½ in the western and northern sectors. In the case of elliptical cut block sites, with diagonals of 1.0 H X 1.5 H, we have found some variations, in the sense that the eastern and the southern sectors receive, at ground surface, approx. 1/5 - 2/5 of the light from an unforested area, the central sector receives a little over 2/3, while the western and the northern sectors receive 4/5 -1/1 of the light from an unforested area, which is also the area with relatively maximum light availability. 2. Surfaces subjected to the progressive felling treatment II - fellings for expandingcut block sites UP VI, Valea Soveții, u.a 127,the Sovata Forestry. Thus, in an elliptical cut block site (1.0 H X 1.5 H) from UP VI, u.a. 127, at1 p.m.,when the sky was overcast, 50% of full light reached the eastern sector, 40% reached the southern sector, approx. 80-90% reached the center of the cut block site, and 75-85% of the amount of light from an unforested area reached the western and the northern sectors at soil surface level. Forest ecosystems are characterized by a great capacity of solar radiation absorption. As a result of selective processes of absorption, reflection and transmission, carried out at the level of the “active surface”, the light regime inside the forest presents a series of distinct features. Light intensity decreases from the top of the canopy to the ground. The decrease is accentuated in the canopy and much slower in the space underneath the canopy, all the way to the ground. Thus, while an average of 66-67% is recorded at the level of the canopy (2/3 of full light), underneath the canopy it reaches 9% (under 1/10 of full light) and only 6-7% of the light from an unforested area is recorded at ground level. Differences are found from one measurement point to another, within the same level, as a result of the foliage structure and the different thickness of the foliage mass located above the measurement point.

Open access

Antonia Odagiu, Ilie Covrig, Camelia Oroian and Mădălina Florina Presecan

Abstract

A particularly important determining factor for the installation and development of seedlings during the early years is their ability to withstand deviations from the normal regime of the climatic elements. Beech seedlings have poor resistance to extreme climate changes. The development of seedlings during the first years can be strongly affected by extreme temperatures. During the research, it was noticed that the frosts which may occur during the second half of April and in early May, before foliation, can cause significant injuries to the plantlets. A large part of the beech seedlings appear in early spring, approximately 7 - 10 days before the foliation of beech trees. The effects of these frosts have also been felt in the nurseries located in the area of the Sovata Forestry, in the case of crops sown in the autumn of the previous year in the Isuica Nursery, situated at an altitude of 520 - 530 m, in the vicinity of Săcădat Creek, and in the case of Solar II Nursery, situated in the village Câmpul Cetaţii, at an altitude of 610 m. The latter nursery is neighbored by the trout farm from Câmpul Cetăţii to the south, by the secondary school to the west, by private residences and estates to the east and by the village road of Câmpul Cetăţii to the north. In both nurseries the emergence percentage of the crops at the end of April was over 90%. Based on the average number of seedlings emerged per area unit, the losses recorded as a result of the frosts from 3-4 May were, in the case of the Isuica Nursery, 89% on 10 May, reaching 97% towards the end of the month. Unlike in the Isuica Nursery, in the Solar II Nursery the losses due to the frost of 3 May were not uniform. The area that was least affected by frost was situated in the immediate proximity of the larch curtain and the secondary school building, where the percentage of losses did not exceed 2%. Moving away from the larch curtain, the percentage increased progressively, reaching, at about 24 m (on the diagonal of the plot), as high as 87%. This percentage was close to that of the (uniform) losses registered in the Isuica Nursery. Thus, the maximum protective effect was recorded up to a distance of about 9 km (0.75 H), where H represents the height of the larch curtain). From this distance, the protective effect exerted by the larch curtain (and the secondary school building with a height of 8 m) started to decrease. While at a distance of about 1 H, the percentage of losses was 17 %, at 1.5 H it reached 61 %, and at approx. 2 H it neared 90 %.

Open access

Ilie Covrig and Valentin Năstăsescu

Abstract

The analysis and drafting of a conclusion regarding the current state of the anthropogenic influence on the forests were conducted by the study of forest planning and other documents that serve the purpose of the research. By following the paths in the forests of Mureş county, several remarks were noted on the state of private and state-owned forest areas: the forester’s intervention in the woods, in terms of the application of silvicultural treatments and forest regeneration and promotion of the basic natural type of forest, the mapping of anthropogenically damaged areas, remarks on the planning of guarding activities and preventing illegal actions in the woods. The actions that cause damage to the forest and the general stock of wood are identified especially in terms of illegal felling. The damages caused though illegal felling during the analyzed period (1970 - 2013), enable us to assert that this kind of damages were recorded throughout the entire analyzed interval. The causes determining a high anthropogenic pressure on the forests are easily identified by the legislative gaps, social poverty of the Romanian society, the influence of the political factor on the national forest strategy, impairment of the forester’s authority in the forests, the dependence of local communities to the forests etc. All these require identification of immediate solutions for the recovery of the anthropogenically damaged areas by afforestation, provision of a sole, coherent and efficient legislative framework, approach of a new concept in terms of supervision and control in the forests.