Experimental evaluation of the initial effects of large-scale thinning on structure and biodiversity of river red gum (Eucalyptus camaldulensis) forests

2018 ◽  
Vol 45 (5) ◽  
pp. 397 ◽  
Author(s):  
Leroy Gonsalves ◽  
Bradley Law ◽  
Rachel Blakey

Context Multi-use management of global forests has seen even-aged, high-stem density regrowth represent >50% of the world’s forest cover. Large areas of river red gum (Eucalyptus camaldulensis) forests have declined in ecological condition. Thinning has been promoted as a tool to reduce competition in dense, young stands of E. camaldulensis regrowth, yet responses of forest structure and fauna to large-scale thinning are largely unclear. Aims To establish a before-after-control-impact experiment to assess responses of forest structure and fauna to large-scale (compartment-level; ~440 ha) silvicultural thinning. Methods We measured immediate (<2 yrs) responses of forest structural components (living, dead and hollow-bearing stem densities, coarse woody debris (CWD) density and volumes and ground cover) and components of biodiversity (bats, birds, volant insects and non-volant mammals) before and after thinning within five control and three impact compartments. Key results Thinning reduced stem density by approximately two-thirds and was associated with a substantial increase in activity and richness of bats and a change in bat species composition. There was no change in richness for birds and non-volant mammals, nor insect biomass in relation to thinning. However, thinning affected composition of non-volant mammals, with the common brushtail possum (Trichosurus vulpecula) and red fox (Vulpes vulpes) less active post-thinning at impact plots relative to control plots. Thinning reduced the density of dead stems, though these were predominantly small (~13 cm diameter at breast height over bark, or dbhob) and mostly lacked hollows. Hollow-bearing tree density was not affected by thinning. Although thinning increased CWD densities, volume of CWD did not change, indicating that thinning contributed small-sized CWD. Thinning did not affect densities of hollow- and fissure-bearing CWD or ground cover, which was low (<7%) in control and impact plots. There were no other negative effects on biodiversity detected. Conclusions Short-term fauna responses to thinning were generally neutral or positive. Implications Ongoing monitoring is required to detect long-term changes that may result from colonisation or altered breeding success after thinning. We recommend that some unthinned stands should be retained throughout the landscape to provide a mosaic forest structure suitable for a diverse fauna.

Author(s):  
С. Л. Подвальный ◽  
О. А. Сотникова ◽  
Я. А. Золотухина

Постановка задачи. В настоящее время формирование современной комфортной городской среды приобретает особое социально-экономическое значение и выдвигается в число приоритетных государственных масштабных программ. В связи с этим необходимо разработать концепцию благоустройства ключевого общественного пространства, а именно: определить основные и сопутствующие функции данной территории, создать эскизное предложение проекта благоустройства с учетом всех необходимых норм и стандартов, внедрить современные технологии. Результаты. Выполнен эскизный дизайн-проект «Аллеи архитекторов» по ул. Орджоникидзе г. Воронеж, включающий в себя основные элементы по зонированию территории, проектированию акцентных объектов и внедрению инновационных технологий «умного города», позволяющих повысить уровень комфорта горожан. Выводы. Благоустройство населенных мест приобретает особое значение в условиях дискомфорта среды. С выполнением комплекса мероприятий, направленных на благоустройство, и с внедрением современных технологий значительно улучшается экологическое состояние, внешний облик города. Оздоровление и модернизация среды, которая окружает человека в городе, благотворно влияет на психофизическое состояние, что особенно важно в период интенсивного роста городов. Statement of the problem. Currently the formation of the modern comfortable urban environment is gaining a special social and economic value and moving forward in the priorities of state large-scale programs. The purpose of development of the concept of improvement of public space is definition of the main and accompanying functions of this territory, design of the outline offer of the project of improvement considering all necessary norms and standards and implementation of modern technologies. Results. The conceptual project of “Alley of Architects” includes the basic elements of territory zoning, design of accent objects and implementation of technologies of a “smart-city”. These elements allow one to increase the level of comfort of inhabitants. Conclusions. Improvement of the inhabited places is of particular importance in the conditions of discomfort of the environment. Carrying out a complex of the actions directed to gardening and improvement, introducing modern technologies, the ecological condition, the physical appearance of the city considerably improves. Improvement and modernization of the environment which surrounds the person in the city influences a psychophysical state well that especially important during intensive growth of the cities.


2003 ◽  
Vol 79 (1) ◽  
pp. 132-146 ◽  
Author(s):  
Dennis Yemshanov ◽  
Ajith H Perera

We reviewed the published knowledge on forest succession in the North American boreal biome for its applicability in modelling forest cover change over large extents. At broader scales, forest succession can be viewed as forest cover change over time. Quantitative case studies of forest succession in peer-reviewed literature are reliable sources of information about changes in forest canopy composition. We reviewed the following aspects of forest succession in literature: disturbances; pathways of post-disturbance forest cover change; timing of successional steps; probabilities of post-disturbance forest cover change, and effects of geographic location and ecological site conditions on forest cover change. The results from studies in the literature, which were mostly based on sample plot observations, appeared to be sufficient to describe boreal forest cover change as a generalized discrete-state transition process, with the discrete states denoted by tree species dominance. In this paper, we outline an approach for incorporating published knowledge on forest succession into stochastic simulation models of boreal forest cover change in a standardized manner. We found that the lack of details in the literature on long-term forest succession, particularly on the influence of pre-disturbance forest cover composition, may be limiting factors in parameterizing simulation models. We suggest that the simulation models based on published information can provide a good foundation as null models, which can be further calibrated as detailed quantitative information on forest cover change becomes available. Key words: probabilistic model, transition matrix, boreal biome, landscape ecology


2004 ◽  
Vol 31 (1) ◽  
pp. 22-29 ◽  
Author(s):  
CURTIS D. HOLDER

Concern about increasing rates of deforestation of tropical forests has resulted in investigations into the viability of local land-use practices and communal forms of governance. The majority of people in Guatemala live in regions where primary forests are absent. Several secondary forests in the highly populated highlands of Guatemala are communally managed forests, and people depend on forest products from these secondary forests for their livelihood. This study examines changes in forest structure and coverage of a native Pinus oocarpa Schiede communally managed forest in San Jose La Arada, Chiquimula in eastern Guatemala from 1954–1996. The pine forest is a municipal-communal property. The municipality has title to the land, however the forests are communal property. Neither forest committees in the villages nor municipal government regulations establish communal management of the pine forest; instead there are customary rules in the villages that guide forest extraction. People from the surrounding villages extract fuelwood, ocote (resin-rich wood harvested from the tree trunk and used for kindling) and timber from the pine forest. The P. oocarpa forest is situated in a seasonally dry region with nutrient-poor and highly eroded soils. Aerial photographs from 1954 and 1987 were compared to estimated changes in forest cover. Changes in forest structure are based on data collected from stand inventories conducted in 1987 and 1996. The pine forest was reduced in area by 14.4%, from 12.39 km2 in 1954 to 10.61 km2 in 1987. Additionally, stand density and basal area were reduced by 12% and 41%, respectively, from 1987–1996. Fuelwood and timber for domestic use were not extracted at a sustainable rate between 1954 and 1996 from the communally managed pine forest in this study. A sustainable-use management plan, in which all villages surrounding the forest participate, is recommended to provide future forest products for the villages.


2021 ◽  
Author(s):  
Yupan Zhang ◽  
Yuichi Onda ◽  
Hiroaki Kato ◽  
Xinchao Sun ◽  
Takashi Gomi

&lt;p&gt;Understory vegetation is an important part of evapotranspiration from forest floor. Forest management changes the forest structure and then affects the understory vegetation biomass (UVB). Quantitative measurement and estimation of&amp;#160; UVB is a step cannot be ignored in the study of forest ecology and forest evapotranspiration. However, large-scale biomass measurement and estimation is challenging. In this study, Structure from Motion (SfM) was adopted simultaneously at two different layers in a plantation forest made by Japanese cedar and Japanese cypress to reconstruct forest structure from understory to above canopy: i) understory drone survey in a 1.1h sub-catchment to generate canopy height model (CHM) based on dense point clouds data derived from a manual low-flying drone under the canopy; ii) Above-canopy drone survey in whole catchment (33.2 ha) to compute canopy openness data based on point clouds of canopy derived from an autonomous flying drone above the canopy. Combined with actual biomass data from field harvesting to develop regression models between the CHM and UVB, which was then used to map spatial distribution of&amp;#160; UVB in sub-catchment. The relationship between UVB and canopy openness data was then developed by overlap analysis. This approach yielded high resolution understory over catchment scale with a point cloud density of more than 20 points/cm&lt;sup&gt;2&lt;/sup&gt;. Strong coefficients of determination (R-squared = 0.75) of the cubic model supported prediction of UVB from CHM, the average UVB was 0.82kg/m&lt;sup&gt;2&lt;/sup&gt; and dominated by low ferns. The corresponding forest canopy openness in this area was 42.48% on average. Overlap analysis show no significant interactions between them in a cubic model with weak predictive power (R-squared &lt; 0.46). Overall, we reconstructed the multi-layered structure of the forest and provided models of UVB. Understory survey has high accuracy for biomass measurement, but it&amp;#8217;s inherently difficult to estimate UVB only based on canopy openness result.&lt;/p&gt;


2007 ◽  
Vol 67 (3) ◽  
pp. 403-411 ◽  
Author(s):  
WG. Silva ◽  
JP. Metzger ◽  
S. Simões ◽  
C Simonetti

Several studies suggest that, on a large scale, relief conditions influence the Atlantic Forest cover. The aim of this work was to explore these relationships on a local scale, in Caucaia do Alto, on the Ibiúna Plateau. Within an area of about 78 km², the distribution of forest cover, divided into two successional stages, was associated with relief attribute data (slope, slope orientation and altitude). The mapping of the vegetation was based on the interpretation of stereoscopic pairs of aerial photographs, from April 2000, on a scale of 1:10,000, while the relief attributes were obtained by geoprocessing from digitalized topographic maps on a scale of 1:10,000. Statistical analyses, based on qui-square tests, revealed that there was a more extensive forest cover, irrespective of the successional stage, in steeper areas (>10 degrees) located at higher altitudes (>923 m), but no influence of the slope orientation. There was no sign of direct influence of relief on the forest cover through environmental gradients that might have contributed to the forest regeneration. Likewise, there was no evidence that these results could have been influenced by the distance from roads or urban areas or with respect to permanent preservation areas. Relief seems to influence the forest cover indirectly, since agricultural land use is preferably made in flatter and lower areas. These results suggest a general distribution pattern of the forest remnants, independent of the scale of study, on which relief indirectly has a strong influence, since it determines human occupation.


Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1542
Author(s):  
Nadezhda V. Genikova ◽  
Viktor N. Mamontov ◽  
Alexander M. Kryshen ◽  
Vladimir A. Kharitonov ◽  
Sergey A. Moshnikov ◽  
...  

Bilberry spruce forests are the most widespread forest type in the European boreal zone. Limiting the clear-cuttings size leads to fragmentation of forest cover and the appearance of large areas of ecotone complexes, composed of forest (F), a transition from forest to the cut-over site under tree canopy (FE), a transition from forest to the cut-over site beyond tree canopy (CE), and the actual clear-cut site (C). Natural regeneration of woody species (spruce, birch, rowan) in the bilberry spruce stand—clear-cut ecotone complex was studied during the first decade after logging. The effects produced by the time since cutting, forest edge aspect, and the ground cover on the emergence and growth of trees and shrubs under forest canopy and openly in the clear-cut were investigated. Estimating the amount and size of different species in the regeneration showed FE and CE width to be 8 m—roughly half the height of first-story trees. Typical forest conditions (F) feature a relatively small amount of regenerating spruce and birch. The most favorable conditions for natural regeneration of spruce in the clear-cut—mature bilberry spruce stand ecotone are at the forest edge in areas of transition both towards the forest and towards the clear-cut (FE and CE). Clear-cut areas farther from the forest edge (C) offer an advantage to regenerating birch, which grows densely and actively in this area.


Author(s):  
A. Sokolov

This paper analyzes the patterns of anthropogenic transformation of landscapes in the Brest region, as measured by value indicators such as forest cover (and geo-ecological coefficient based on it), the density of rural population, the share of residential landscapes. Correlation between nature properties of landscapes underlying their classification, and these indicators was detected. It was found that the genera of landscapes, which represent the maximum disturbance, are secondary-moraine and moraine-outwash landscapes, the subgenera of landscapes are with a cover and a discontinuous cover of glacial sandy loams. The least disturbance is distinctive for secondary water-glacial and alluvial terraced landscapes and among genera – with superficial cover of water-glacial sands and with superficial bedding of peat and sand. The necessity of protected areas network optimization is shown. The results showed a significant imbalance between the ecological condition of the landscape which belong to certain classification groups and their representation in the protected areas system of the region. Landscapes with the worst ecological situation, as a rule, occupy a small proportion among all landscapes of protected areas. This case does not allow carrying out fully the tasks of protection and restoration of the diversity of ecosystems of the region. Among genera share of protected areas is much greater than the share of the region generally occupy wetland and floodplain landscapes. Moraine-outwash landscapes, characterized by a critical environmental condition are not represented in the protected areas system. Among subgenera areas in protected territories are far larger than in the region are characterized for landscapes with superficial stratification of peat and sand, considerably smaller – for landscapes with a cover of water-glacial sandy loams and loams, ecological condition of which is estimated as critical. Thus, the existing network of protected areas in Brest region needs to be optimized be including those genera and subgenera of landscapes, which are characterized by the worst environmental condition and restore these areas to natural communities.


2020 ◽  
Author(s):  
Szewczyk Grzegorz ◽  
Krzysztof Lipka ◽  
Piotr Wężyk ◽  
Karolina Zięba-Kulawik ◽  
Monika Winczek

As a result of environmental changes, assessment indexes for the agricultural landscape have been changing dramatically. Being at the interface of human activity and the natural environment, hunting is particularly sensitive to environmental changes, such as increasing deforestation or large-scale farming. The classical categorisation of hunting grounds takes into account the area, forest cover, number of forest complexes, fertility of forest habitats, lack of continuity of areas potentially favourable to wild animals. Landscape assessment methods used in architecture often better reflect the actual breeding and hunting value of a given area, especially in relation to fields and forests. The forest-field mosaic, large spatial fragmentation as well as interweaving of natural environment elements with buildings do not have to be the factors that limit the numbers of small game. Identification of the constituents of architectural-landscape interiors: content and significance assessment, determination of the functional role or assessment based on the general environmental values being represented take into account factors important for the existence of game, in particular small game.


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