Afforestation Process Research Articles

Street trees reduce the negative effects of urbanization on birds.

The effects of streets on biodiversity is an important aspect of urban ecology, but it has been neglected worldwide. Several vegetation attributes (e.g. street tree density and diversity) have important effects on biodiversity and ecological processes. In this study, we evaluated the influences of urban vegetation—represented by characteristics of street trees (canopy size, proportion of native tree species and tree species richness)—and characteristics of the landscape (distance to parks and vegetation quantity), and human impacts (human population size and exposure to noise) on taxonomic data and functional diversity indices of the bird community inhabiting streets. The study area was the southern region of Belo Horizonte (Minas Gerais, Brazil), a largely urbanized city in the understudied Neotropical region. Bird data were collected on 60 point count locations distributed across the streets of the landscape. We used a series of competing GLM models (using Akaike's information criterion for small sample sizes) to assess the relative contribution of the different sets of variables to explain the observed patterns. Seventy-three bird species were observed exploiting the streets: native species were the most abundant and frequent throughout this landscape. The bird community's functional richness and Rao's Quadratic Entropy presented values lower than 0.5. Therefore, this landscape was favoring few functional traits. Exposure to noise was the most limiting factor for this bird community. However, the average size of arboreal patches and, especially the characteristics of street trees, were able to reduce the negative effects of noise on the bird community. These results show the importance of adequately planning the urban afforestation process: increasing tree species richness, preserving large trees and planting more native trees species in the streets are management practices that will increase bird species richness, abundance and community functional aspects and consequently improve human wellbeing and quality of life.

Distribuição atual e potencial de espécies do género Acacia Mill. (Fabaceae) na Ilha da Madeira e implicações para a diversidade florística em contexto de invasão

As espécies mais comuns de Acacia que ocorrem na Ilha da Madeira foram introduzidas durante os séculos XIX e XX, como ornamentais ou para uso florestal, tendo-se tornado espécies invasoras. De forma a avaliar os impactes associados à invasão por estas espécies, neste trabalho procede-se à i) caracterização da distribuição atual de espécies do género Acacia Mill. na Ilha da Madeira, com base na recolha de presenças em campo a partir de um processo de amostragem sistemática e estratificada, assegurando que todo o gradiente ambiental da ilha é amostrado; ii) avaliam-se os impactes na diversidade florística das áreas invadidas, com base na comparação de inventários florísticos de comunidades nativas climácicas (laurissilva, zambujal) com os de áreas invadidas por acácia-austrália (Acacia melanoxylon R. BR.) e acácia negra (Acacia mearnsii De Willd.), as espécies que apresentam distribuição mais ampla na ilha; iii) avalia-se a distribuição potencial destas espécies, com base em modelos de base estatística, suportados no conceito de nicho ecológico; e iv) confirma-se o caráter invasor da acácia negra, através da avaliação da dinâmica a longo prazo com recurso a técnica de refotografia (Repeat Landscape Photography Technique). Em termos de resultados, tendo em conta o evidente empobrecimento florístico que os acaciais representam em co mparação com as comunidades nativas clímax que encabeçam as séries climatófilas, considerando a importância das áreas que são potencialmente adequadas à presença das espécies em análise, e dado o seu caráter invasor, confirmado no caso da acácia negra, podem considerar-se estas espécies como verdadeiras ameaças à diversidade na Ilha da Madeira.https://doi.org/10.14195/0871-1623_35_6

Long‐term Effects of Pine Plantations on Soil Quality in Southern Spain

AbstractThis work evaluated how pine plantations established on old fields and degraded lands influence soil properties in comparison with adjacent unplanted areas that undergo into secondary succession, and native forests, analysing the effects of abiotic variables and stand characteristics in the afforestation process. Thirty‐two paired sites (pine plantations versus unplanted areas) and 10 native forests were selected in the SE Spain. In total, 74 soil profiles were studied, and 222 composite soil samples were collected at three different depths. Soil organic carbon, cation exchange capacity, and C : N ratio showed significantly greater values in pine plantations in relation to the unplanted areas (0–5 cm), and the mean values of soil organic carbon, nitrogen (N), C : N ratio, and cation exchange capacity in these pine plantations were similar to those found under native forests. Only K+ concentrations were clearly higher in the native forests than in the other land uses for all depths analysed. Pine plantations in the drier and warmer areas showed lower soil quality in relation to the paired unplanted areas, as well as the younger and denser ones; it may be because under these situations, more time is needed to produce an improvement. In fact, the paired net variations increased with the stand age and/or tree size. In conclusion, pine plantations were in general more efficient in improving parameters related to soil quality, especially in locations with high soil water retention capacity, which in our study area were found at higher and cooler elevations. Copyright © 2016 John Wiley & Sons, Ltd.

Respuesta hidro-sedimentaria en dos cuencas mediterráneas representativas afectadas por el cambio global

El abandono de tierras de cultivo marginales durante la segunda mitad del siglo XX ha supuesto un proceso de forestación en la Europa mediterránea. Paralelamente, esta mayor disponibilidad de biomasa ha incrementado la superficie afectada por incendios forestales. Con el objetivo de establecer el efecto de estos procesos de cambio global en la respuesta hidrosedimentaria, se comparan dos cuencas de drenaje mediterráneas forestadas cuyas laderas fueron usadas intensamente por la agricultura mediante aterrazamiento hasta los años 60 del siglo XX. Una de ellas, además, afectada periódicamente por incendios forestales. Dicha comparación se llevó a cabo mediante la monitorización del caudal y del transporte de sedimento en suspensión durante un período de estudio representativo (i.e., enero-septiembre 2014). Los valores de escorrentía y producción de sedimento en suspensión muestran una diferencia de dos o más órdenes de magnitud entre ambas cuencas, siendo mayor en aquella no afectada por incendios forestales (i.e., 469 mm y 14 t km-2 frente a 1 mm y 0,003 t km-2). Este hecho es propiciado por una contrastada dinámica pluviométrica debido a la ubicación de las cuencas en distintas áreas de afinidad de precipitación en la isla de Mallorca. Por ende, los valores de producción de sedimento en suspensión fueron bajos o muy bajos (i.e., <15 t a-1 km-2) si se comparan con valores de la Europa mediterránea. Aquí, la masiva presencia de bancales y litologías carbonatadas reducen significativamente la conectividad ladera-cauce, limitando la transferencia de agua y sedimento.

Linkages of C:N:P stoichiometry and bacterial community in soil following afforestation of former farmland

Ecological stoichiometry (C:N:P ratios) in soil plays an important role in ecosystem dynamics and functioning; however, its relationship with below-ground microbial diversity following afforestation remains poorly understood. To illustrate the linkage of C, N, and P in soil and microbial biomass, and the effect on the soil bacterial community, soil samples were collected from farmland and from three afforested land, namely Robinia pseudoacacia L., Caragana korshinskii Kom, and abandoned land, which have been arable for the past 40years. Quantitative PCR and Illumina sequencing of the 16S rRNA genes were used to analyze soil bacterial abundance, diversity, and composition. Additionally, soil properties and C, N, and P levels in soil and microbial biomass were estimated. The results revealed that C, N, and P levels in soil and microbial biomass increased following afforestation, with a significant correlation observed, especially for the N:P ratio. Additionally, a rise in 〈alpha〉- and 〈beta〉-diversity of soil bacteria was observed in response to afforestation, and was linked to soil C:P and N:P ratios. Soil bacterial phyla with high relative abundance (relative abundance>1%) across all samples showed inconsistent directional trends in the composition response after afforestation. An increased abundance of Proteobacteria, Acidobacteria, and Nitrospirae were observed, while the abundance of Chloroflexi was opposite (P<0.05) following afforestation. Those were largely influenced by changes in the N:P ratio in soil and microbial biomass. Taken together, significantly increased N:P ratio in soil reflected the deficient P that would be limited for increased microbial biomass and diversity. Thus, P status should be an important factor for sustainable restoration of the forest during the process of afforestation.

CHANGE IN LAND USE IN HALOZE IN THE PERIOD 2000-2015 WITH SPECIAL REFERENCE TO WINE-GROWING AREAS

Haloze is among demographically most vulnerable Slovenian regions. The unfavorable demographic and economic development is also reflected in the revised land use. The processes of change in land use over the past decade indicate extensification of agricultural production due to a significant process of greening and afforestation. The article presents changes in land use between 2000 and 2015. Having in mind that Haloze, especially its eastern part, was already in the Middle Ages known for the best vineyard sites, a high share of winegrowing areas and good wine, we paid special attention to changes of winegrowing areas and utilization of wine-growing potential.

Removal of competitive native species combined with tree planting can accelerate the initial afforestation process: an experiment in an old field in Japan invaded by dwarf bamboo and kudzu

Restoring natural forests after field abandonment is a land management objective that fosters the recovery of forest biodiversity. We performed seeding and transplanting of native tree species 40 years after the abandonment of an arable field that became dominated by a dwarf bamboo (Pleioblastus chino (Franch. et Sav.) Makino) and by kudzu (Pueraria lobata (Willd.) Ohwi). By permutation tests, the removal of competing vegetation (gap creation) significantly increased the survival of three seeded species of Fagaceae and of eight transplanted species. In contrast, intact vegetation prevented most individuals of all species from surviving for 1 year after planting. The lack of natural recruitment of Fagaceae in the nonseeded subplots indicated that seed limitation was a cause of the slow afforestation. Although litter accumulation in gaps at the time of seeding slightly increased survival for late-germinating Quercus myrsinifolia Blume and Castanopsis sieboldii (Makino) Hatus. ex T. Yamaz. et Mashiba, the effect was not consistent among plots and was not statistically significant. Our results suggest that for successful afforestation using native trees in abandoned fields, it will be necessary to remove competitive native species to avoid severe limitations on microsite availability and that simultaneous tree establishment by seeding or transplanting should be implemented to accelerate the establishment of native tree species.

Assessment and illustration of cultural ecosystem services at the local scale – A retrospective trend analysis

There is a need to develop non-monetary methods for the assessment of cultural ecosystem services, in order to integrate them into the ES framework in a more balanced way. With this in mind, an adequate and comprehensive indicator base and mapping methods are required to communicate and discuss cultural ecosystem services, for it to be understood holistically. Referring to land use changes as an important driver for ES changes, we demonstrate the analysis of cultural ecosystem services trends, in a retrospective, as a supporting tool to better understand social and natural interactions as drivers behind land use changes, which are reflected in the landscape scene. There are two main outcomes of this study: (1) first, we developed and tested a catalogue of indicators as an approach to evaluate cultural ecosystem services trends at the local scale and (2) we established a mapping method for cultural ecosystem services trends in parallel with land use changes. This we did following the example of the afforestation processes which had taken place since the 19th century in the suburban area of Göttingen (Lower Saxony/Germany), called Hainberg. Our main conclusion is that cultural ecosystem services trends can indicate the reasons and drivers for land use changes that can be beneficial to forest/landscape management issues by means of the restoration of lost services. The proposed assessment method can be integrated into the development of future landscape plans, e.g. by providing information on historical guiding principles.

A half-century analysis of landscape dynamics in southern Québec, Canada

We studied landscape dynamics for three time periods (<1950, 1965, and 1997) along a gradient of agricultural intensity from highly intensive agriculture to forested areas in southern Québec. Air photos were analyzed to obtain long-term information on land cover (crop and habitat types) and linear habitats (hedgerows and riparian habitats) and landscape metrics were calculated to quantify changes in habitat configuration. Anthropogenic areas increased in all types of landscapes but mostly occurred in the highly disturbed cash crop dominated landscape. Perennial crops (pasture and hayfields) were largely converted into annual crops (corn and soybean) between 1965 and 1997. The coalescence of annual crop fields resulted in a more homogeneous agricultural landscape. Old fields and forest cover was consistently low and forest fragmentation remained stable through time in the intensive agriculture landscapes. However, forest cover increased and forest fragmentation receded in the forest-dominated landscapes following farm abandonment and the transition of old fields into forests. Tree-dominated hedgerows and riparian habitats increased in areas with intensive agriculture. Observed changes in land cover classes are related to proximate factors, such as surficial deposits and topography. Agriculture intensification occurred in areas highly suitable for agriculture whereas farm abandonment was observed in poor-quality agriculture terrains. Large-scale conversion of perennial crops into annual crops along with continued urbanization exerts strong pressures on residual natural habitats and their inhabiting wildlife. The afforestation process occurring in the more forested landscapes along with the addition of tree-dominated hedgerows and riparian habitats in the agriculture-dominated landscapes should improve landscape ecological value.

Is rewetting enough to recover Sphagnum and associated peat-accumulating species in traditionally exploited bogs?

When restoring ecosystems, the simple removal of stresses causing degradation may seem preferable over other more costly and time consuming approaches. However, some restoration techniques can be implemented at reasonable cost and with increased efficiency in certain cases. We examined the successional trajectories of vegetation within abandoned block-cut peatlands in a major peat-producing region of Eastern Canada to evaluate whether the use of rewetting as a restoration technique can assist in the recovery of a typical bog plant community dominated by Sphagnum compared to spontaneous recolonization alone. We surveyed a total of 55 trenches in 6 peatlands twice, ~25 and ~35 years after the cessation of peat extraction. Canonical ordinations evidenced a generalized process of afforestation during the decade studied, partially driven by agricultural drainage in the surrounding landscape. Plant communities were dominated by ericaceous shrubs that hampered the spontaneous recovery of a Sphagnum-dominated system typical of bogs in the short and medium-term. Three of the six peatlands surveyed were partially restored by blocking drainage ditches. There, we surveyed plant composition in rewetted (28) and non-rewetted (26) trenches and observed that rewetting mitigated the increase in tree dominance, decreased the dominance by ericaceous shrubs, and favored the spread of non-vascular species with a wet habitat preference (notably Sphagnum species from the Cuspidata section). We conclude that the use of low intervention restoration techniques in block-cut bogs, such as the blockage of former drainage ditches, can re-orient undesired vegetation trajectories driven by spontaneous recolonization alone.

The perception of abandoned farmland by local people and experts: Landscape value and perspectives on future land use

Abandonment of agricultural land is a common feature of areas undergoing a range of urbanisation and marginalisation processes across Europe and beyond. This is also the case in Latvia, particularly in the period since 1990, when after regaining independence from the Soviet Union land was restored to its previous owners or their descendants. Many of these people have moved to cities and lack the interest in or the necessary capital for starting farming enterprises. As a result, large areas of land were abandoned, leading to spontaneous afforestation and with associated changes in landscape structure, ecological function and aesthetic value. While there has been an increase in research interest in the processes associated with abandoned farmland, there are still very few studies on people's perception of such areas. The aim of this study was to extend previous research on the ecological aspects of the afforestation processes by assessing the opinions of rural residents and of land use experts about recent landscape change and potential solutions for the re-use of abandoned agricultural land. The results confirmed earlier research showing that in general attitudes towards abandoned agriculture land are rather negative, it being mainly associated with insufficient use and desolation, while very few respondents perceive it positively for its naturalness. Nevertheless, when asked to evaluate four different forest colonisation patterns, respondents expressed a preference for a mosaic pattern as being better for the appearance of the landscape as well as for biodiversity.

Land Cover Changes along the Iron Curtain 1990–2006

The article analyses land cover changes along the Iron Curtain in the period 1990–2006. CORINE land cover state and land cover change datasets are used to evaluate differences in land cover structure in 1990 and in land cover changes between the eastern (from former German Democratic Republic to Hungary) and western (former Federal Republic of Germany and Austria) border sections along the Iron Curtain. The results confirm different representation of individual land cover categories on the eastern and western sides. Different intensity of changes at the eastern and western border sections has been confirmed, too. More intense land cover changes were detected in the “East” after 1990. The highest intensity of changes was recorded at the Czech border sections where rather strong process of afforestation took place, together with retreat of intensive agriculture (changes on more than 8% of the area between 1990 and 2000). On the contrary, the Austrian border section was the most stable area (changes only on 0.13% of the area).

제주도 난대림에서 노루 뿔의 성장과정에 의한 어린나무 박피에 관한 연구

산림에서 나무껍질이 벗겨지는 피해는 노루를 비롯한 사슴과에 속하는 포유류에 의해 발생하며 먹이 부족이 주요 원인이다. 그러나 제주도에서는 뿔이 녹각으로 되는 과정에서 벨벳을 벗겨내는 행동에 의해 나무껍질이 벗겨지는 피해가 발생하여 이들을 살펴보았다. 국립산림과학원 한남시험림내의 해발 400m에서 500m 사이에 위치한 6km구간의 임도 주변 5m지역을 대상으로 2011년 9월 9일부터 10월 4일까지 맑은날을 택하여 본조사를 실시하였다. 노루가 뿔로 긁은 피해목은 총 25종, 267본이었으며 낙엽활엽수가 18종 134본, 상록활엽수가 5종 71본, 나머지 2종 62본은 침엽수였다. 뿔 긁기로 가장 선호하는 수종은 굴거리나무(Daphniphyllum macropodum), 삼나무(Cryptomeria japonica), 비목(Lindera erythrocarpa), 누리장나무(Clerodendrum trichotomum), 산초나무(Zanthoxylum schinifolium) 순이었다. 피해목은 주로 3~4년생의 어린나무이며 평균 수고는 <TEX>$120.7{\pm}42.4cm$</TEX>이었고, 지상 5cm 높이에서의 직경은 <TEX>$1.5{\pm}0.5cm$</TEX>, 피해 시작점(최저점)은 지상에서부터 평균 <TEX>$22.1{\pm}10.1cm$</TEX> 지점이었고, 피해길이는 평균 <TEX>$27.5{\pm}10.6cm$</TEX>이었다. 나무껍질이 벗겨지면 이차적으로 균류의 침입을 받게 되며 이로 인해 어린나무의 외형이 변하거나 죽게 되어 난대림의 향후 종 구성에 영향을 야기할 수 있다. 기후변화에 따른 제주도 산림의 식생변화가 예견되는 시점에서 노루의 뿔에 의한 피해는 난대림의 자연 갱신은 물론 조림과 묘목생산 그리고 지속적인 산림경영에 영향을 미칠 것으로 판단된다. Peeling damage of trees is usually caused by Cervidae such as deer, roe deer because of the lack of food in forests. However, it happens as part of the developing of antlers in Jeju Island when the roe deer try to remove the Velvet-the skin of the antlers. The research area is the Hannam experimental forest (400 m up to 500 m above sea level) of Korea Forest Research Institute in Jeju Island, and the survey was carried out along the 6 km long of forest road with 5 m width on both sides. Twenty five tree species (total 267 stands) are damaged by peeling; 18 (134 stands) deciduous broad-leaved species, 5 (71 stands) in evergreen broad-leaved species, 2 (62 stands) coniferous species. The most common damaged species are in order of Daphniphyllum macropodum, Cryptomeria japonica, Lindera erythrocarpa, Clerodendrum trichotomum, Zanthoxylum schinifolium. Mainly damaged trees are approximately 3~4 years old saplings, and they show the mean height <TEX>$120.7{\pm}42.4cm$</TEX>, diameter measured at 5 cm height <TEX>$1.5{\pm}0.5cm$</TEX>. The Lowest peeling beginning height is <TEX>$22.1{\pm}10.1cm$</TEX>, and the mean length of peeling is <TEX>$27.5{\pm}10.6cm$</TEX>. Once the peeling damage happens, the saplings are infected by fungi secondly, and are distorted or dead, therefore the future structure of warm-temperate forests could be in influenced in species. Warm-temperate forest landscape and species change related to the climate change is a rising issue in Jeju Island. However the changes caused by peeling damage also could be an important issue in the natural process of forest environment, afforestation, local nursery and sustainable forest management of Jeju Island.

Climate warming and vegetation response after Heinrich event 1 (16 700–16 000 cal yr BP) in Europe south of the Alps

Abstract. Chironomids preserved in a sediment core from Lago di Origlio (416 m a.s.l.), a lake in the foreland of the Southern Swiss Alps, allowed quantitative reconstruction of Late Glacial and Early Holocene summer temperatures using a combined Swiss–Norwegian temperature inference model based on chironomid assemblages from 274 lakes. We reconstruct July air temperatures of ca. 10 °C between 17 300 and 16 000 cal yr BP, a rather abrupt warming to ca. 12.0 °C at ca. 16 500–16 000 cal yr BP, and a strong temperature increase at the transition to the Bølling/Allerød interstadial with average temperatures of about 14 °C. During the Younger Dryas and earliest Holocene similar temperatures are reconstructed as for the interstadial. The rather abrupt warming at 16 500–16 000 cal yr BP is consistent with sea-surface temperature as well as speleothem records, which indicate a warming after the end of Heinrich event 1 (sensu stricto) and before the Bølling/Allerød interstadial in southern Europe and the Mediterranean Sea. Pollen records from Origlio and other sites in southern Switzerland and northern Italy indicate an early reforestation of the lowlands 2000–1500 yr prior to the large-scale afforestation of Central Europe at the onset of the Bølling/Allerød period at ca. 14 700–14 600 cal yr BP. Our results suggest that these early afforestation processes in the formerly glaciated areas of northern Italy and southern Switzerland have been promoted by increasing temperatures.

Environmental framework to visualize emergent artificial forest ecosystems

We propose an environmental framework for simulation and visualization of woody plant forests. A complex application software system develops and animates a spontaneous afforestation process within this environment. The system considers several environmental properties and combines computer animation with artificial life. The main goal of the presented software system is to use it in computer animation for synthesis of natural environments and visual analysis of their natural look credibility. The afforestation process is modeled as an ecosystem simulation, where trees struggle for survival based on several growth factors. A detailed description of the procedures for simulating tree growth and the factors that might influence tree growth is provided. All the tree growth simulation procedures and factors are biologically inspired. They have been defined mathematically in the paper by designing a bottom-up agent model which emerges the artificial tree distribution by mediating to the simulation.A flexible and adaptable procedural 3D model is used to visualize trees. Also, growth of individual trees is animated, from development of branch complexity to per-leaf precision, which allows a very realistic perception of the emerging ecosystem. The visualization of trees is sped up so that the models of trees have progressively lower-details proportional to the distance from a certain point of view. Locations and maturity of visualized trees are obtained from the ecosystem simulation results, and the afforestation process is animated over several centuries. The natural look of the artificial tree distribution is confirmed visually and statistically. Visually, it is confirmed from rendered sequences, and statistically, from graphs of tree species populations. Several patterns emerge permanently, such as the number of trees in the ecosystem simulation increasing exponentially and trees growing in communities.

Multitemporal analysis of forest fragmentation in the upstream region of the Nenjiang River Basin, Northeast China

The present study investigated the forest transition and fragmentation process using historical topographic maps and multi-temporal satellite images in the upstream region of Nenjiang River Basin, Northeast China from 1954 to 2010. Area-weighted centroid method, associated with the area-weighted mean patch fractal dimension (AWMPFD) and core area percentage of landscape (CPL), were used to estimate the spatial movement of forest as well as its spatial fragmentation process. The forest was further classified into high dense forest, low dense forest, and shrub forest to analyze the forest transition process, among these forest types or between forests and other landscape types. An obvious deforestation was observed during 1954–2000, with two different fragmentation processes in two periods: the first fragmentation process from 1954 to 1976 was mainly observed along the ecotone between forest and other landscape classes while the second fragmentation process from 1976 to 2000 was observed both in the ectone and interior area of forest patches. The afforestation process was observed during 2000–2010 due to the issue of a series of policies by the national and local government. GIS-based landscape index, coupled with socio-economic and political driving forces analysis, proved its unique value and effective in assessing landscape pattern and dynamics.

Effects of an afforestation process on plant species richness: A retrogressive analysis

Effective conservation of biodiversity in the face of increasing human impacts and global environmental changes requires accurate measurement of key trends and alternative management actions at landscape scales. Past ecological conditions are certainly important key factors in determining the present species diversity patterns and the inclusion of such factors (e.g. by historical cartographic data) can dramatically improve the predictive power of ecological models. In this paper we applied a retrogressive approach with the aim of simulating secondary forest regrowth effects on plant species diversity using present field data and historic land-use maps. The field data from an extensive sample were here used to model the temporal species richness change among the forest areas in the last 60 years. In order to rebuild the past species pool matrix using present field data and historical land use map, we applied a nearest neighbour selection using spatial query. Species-based rarefaction curves were derived for the two dates (1954 and 2010); the two datasets have been interpolated using inverse distance weighted algorithm, obtaining two maps showing the distribution of plant species richness for the two dates.The results showed that the cessation of human pressure on semi-natural areas and the consequent forest recovery, resulted in a decrease of vascular plant as a woodland flora replaces the open habitats flora. This study also showed that secondary forest regrowth and its effect on plant species diversity may be revealed by a retrogressive analysis, which represent a valid support in case of high uncertainty or absence of historical data.

Landscape metrics and topographical determinants of large-scale forest dynamics in a Mediterranean landscape

The analysis of land-use and land-cover change has long been a key topic in Landscape Ecology. In particular, forest fragmentation is known to affect species composition and diversity, thus threatening the integrity of forest habitats. This paper examines the forest cover dynamics in a Mediterranean area (the Province of Siena, central Italy), by comparing historical (1933) and recent forest maps (2000). The historical map has been geo-referenced, digitised in a GIS environment, and classified in three forest classes: broad-leaved, conifer and mixed forests. The same classification was used for the recent forest map. Image processing techniques and landscape pattern metrics were applied to quantify the changes in forest cover patterns, while appropriate statistical descriptors were adopted to investigate the relationship between land-cover changes and topographical factors. A general afforestation process was detected in the investigated area over the period 1933–2000, resulting in a high landscape transformation overall considering zones with higher elevation and slope. The forest landscape structure changed in terms of decreased fragmentation and patchiness. The general trend observed in this area was in line with previous results achieved in similar ecological situations, thus reinforcing the need to link landscape change patterns with appropriate management decisions.

The Polish landscape changing due to forest policy and forest management

This paper presents an analysis of policy application in Poland affecting landscape and forest management changes designed for an ecological restoration. “Ecological” policy was introduced in Poland in 1991 (Bill on Forests) and 1995-1999 (Decree 11 and 11A). To analyse the effectiveness of the policy and its impact on landscape change, the study uses five selected indicators: 1) species distribution, 2) methods of final felling, 3) forest functions in terms of protection and economic role, 4) cost structure and 5) wood production. The analysis shows that some of the ecological ideas were applied years before official documents were issued: species composition change, in favour of broadleaves has been carried out since 1945; since 1975, considerable growth in protective areas has been observed, doubling from 22.5 to 47.5% by 2006; timber resources have also grown by 50% in the last 35 years. After 1991, when the new policy was introduced, change in these indicators was more rapid. More direct and visible examples of policy applications in the last 15 years are observed in 1) the reduction of clearcuts: in 2005 this was at its lowest level in comparison with the previous 15 years and amounted to 19.9%; 2) the focus on protection: the cost of forest and fire protection in 2006 was the third largest expense in the State Forests budget, special attention was paid to reconstruction in order to increase water retention, 3) the afforestation process: this has doubled in intensity in the last decade compared with the previous decade. Nevertheless, organised landscape change is also accompanied by natural calamities, of which fires and windbreaks are most severe.

Spatial analysis of rockfall activity, bounce heights and geomorphic changes over the last 50 years – A case study using dendrogeomorphology

Tree-ring series have been used to reconstruct 50 years of rockfall behavior on a slope near Saas Balen (Swiss Alps). A total of 796 cores and 141 cross sections from 191 severely injured conifer trees ( Larix decidua Mill., Picea abies (L.) Karst. and Pinus cembra L.), combined with a series of aerial photographs, were used to investigate the evolution of the forest stand so as (i) to reconstruct past rockfall rates; (ii) to analyze the spatial behavior of maximum bounce heights; and (iii) to analyze the spatial comportment of rockfall activity over the last five decades. Tree-ring analysis permitted the reconstruction of the age distribution at the study site; results were in perfect agreement with the afforestation process shown in the aerial photographs. The oldest are located in the lower, central part of the study site; the youngest individuals at its uppermost lateral boundaries. Reconstructed rockfall rates reveal strong interannual variations and single event years with increased activity, namely in 1960/1961 and 1995. Spatial analysis of the maximum bounce heights indicate highest values at the lateral boundaries and lowest heights in the lower central part of the forest stand, where a big boulder seems to shield trees growing below it. The spatial analysis of past rockfall activity shows high active zones at the uppermost north-facing boundaries of the forest and least active zones in the lowermost central part of the studied stand. The high rockfall activity at the slope is expressed by a mean rockfall rate of > 1 event m − 1 y − 1 .