Coupled ecological-social dynamics in a forested landscape: spatial interactions and information flow

We develop an agent-based model for forest harvesting to study how interactions between neighboring land parcels and the degree of information flow among landowners influence harvesting patterns. We assume a forest is composed of a number of land parcels that are individually managed. Each parcel is either mature forested, just-harvested, or immature forested. The state transition of each parcel is described by a Markov chain that incorporates the successional dynamics of the forest ecosystem and landowners' decisions about harvesting. Landowners decide to cut trees based on the expected discounted utility of forested vs. harvested land. One landowner's decision to cut trees is assumed to cause the degradation of ecosystem services on the downstream forested parcels. We investigated two different scenarios: in a strongly-connected society, landowners are familiar with each other and have full information regarding the behavior of other landowners. In a weakly-connected society, landowners do not communicate and therefore need to make subjective predictions about the behavior of others without adequate information. Regardless of the type of society, we observed that the spatial interaction between management units caused a chain reaction of tree harvesting in the neighborhood even when healthy forested land provided greater utility than harvested land. The harvest rate was higher in a weakly-connected society than that in a strongly-connected society. If landowners employed a long-term perspective, the harvest rate declined, and a more robust forested landscape emerged. Our results highlight the importance of institutional arrangements that encourage a long-term perspective and increased information flow among landowners in order to achieve successful forest management.     

The role of economic incentives and social norms in forest resource management

Forests are experiencing increasing pressure from human activities, which is leading to rapid deforestation and loss of ecosystem services. Although deforestation occurs for a wide range of reasons, one important reason is that landowners lack a long-term management view. I suggest that both economic incentives and social norms will work differently to reduce landowners’ motivation to deforest and to help landowners identify the long-term benefits that will be obtained by sacrificing short-term gain.     

土地利用/景观生态学研究中的马尔可夫链统计性质分析

马尔可夫链在土地利用和景观生态学研究中得到了广泛应用,而应用中通常假设土地利用变化为满足马尔可夫性的一阶时齐马尔可夫链,对马尔可夫链的统计性质是否成立却很少进行检验.本文以北京市土地利用变化监测数据为算例,提出了马尔可夫链统计性质的皮尔逊χ² 拟合优度检验方法.检验结果表明,土地利用研究中通常假设的时齐性和马尔可夫性(一阶性)在统计学上并不成立,即北京土地利用演变过程为非时齐的高阶马尔可夫链.相对于马尔可夫统计性质的似然比检验中转移概率大于零的要求,皮尔逊χ²检验对转移概率的要求相对宽松,允许转移概率为零,所以应用的范围较似然比检验更为广泛.     

Landscape dynamics and their effect on the functional connectivity of a Mediterranean landscape in Chile

Land use and cover changes have been identified as a major factor contributing to shape landscape structure and biodiversity patterns, particulary in areas with a long history of human occupation and habitat fragmentation, such as the Mediterranean landscapes. However, the existing studies on landscape change indicators for Mediterranean areas have mostly focused in Europe, while for other Mediterranean zones, and especially for South America, there is a serious lack of knowledge concerning the impact of landscape dynamics on ecological processes. Further research on this topic is urgently needed, given the high biodiversity levels and the rapidly increasing rates of human modification in the Mediterranean landscapes of South America. For this purpose, we investigated the dynamics of a landscape in the semiarid region of the Mediterranean zone of Chile, and measured the effect of those dynamics on functional connectivity, during a period of about four decades (1975–2011). Landscape connectivity indicators were extracted from a series of Landsat images. The Equivalent Connnected Area index (ECA) was used as indicator of connectivity trends, and was evaluated for three representative distances of seed dispersal in the study area (150 m, 500 m and 1000 m). In addition, the patches that most contribute to maintain the present connectivity, and their roles as connectivity providers, were identified through a set of commensurable indicators: betweenness centrality and the fractions (intra, flux connector) of the Integral Index of Connectivity. We found that these indicators were useful to detect and summarize a number of previously unreported trends in these Mediterranean landscapes. First, population growth and economic development were compatible with an increase in functional connectivity for forest habitats, mainly because the abandonment of marginal agricultural lands and their subsequent conversion to espinals (Acacia caven) triggered vegetation succession towards secondary forests. Second, increased forest connectivity was not associated to a decrease in the characteristic heterogeneity of Mediterranean landscapes. Third, many patches of espinal, despite being commonly regarded as of poor conservation value, were crucial to promote connectivity by acting as stepping stones among other patches with higher habitat quality. The approach here presented provides a combined assessment of landscape structure, function and change that should be valuable and applicable to deliver operational indicators in dynamic landscapes in South America and other Mediterranean regions.     

黄土高原小流域景观多样性动态分析

以纸坊沟为例,在地理信息系统支持下获得计算景观多样性的有关参数,运用斑块大小及数量、平均分维数、多样性指数、优势度、均匀度、破碎度和聚集度等指标,对黄土高原小流域40年来景观多样性动态变化进行了分析．结果表明,40年来,在以人类活动干预和植被内源演替为主要驱动力的共同作用下,该流域斑块总数增加,旱地基质逐渐被林地、草地等其它景观基质所取代,景观格局趋于破碎,景观类型多样性和均匀度增加,且后20年景观多样性的变化幅度远远大于前20年的变化幅度．目前流域已经由1958年以旱地为基质的高度均质化的景观生态系统转化为与当地地带性景观相适应的以草地和林地为基质的高度异质化的景观生态系统,生态系统结构、功能已具有较强的稳定性．     

Best of both worlds: Combining ecological and social research to inform conservation decisions in a Neotropical biodiversity hotspot

Conservation decision is a challenging and risky task when it aims at prioritizing species or protected areas (PAs) to prevent extinction while ensuring fair treatment of all stakeholders. Better conservation decisions are those made upon a broader evidence base that includes both ecological and social considerations. However, in some of the most biodiverse ecosystems on Earth — tropical forests, for instance — multicriteria decision-making has been constrained by the following (i) ecological and social datasets available have been obtained in an independent, non-integrated manner, with social data typically more scarce than ecological ones, and (ii) capacity in social and/or interdisciplinary data analysis among decision-maker is limited. We describe a conservation prioritization exercise that combined findings from independent ecological and social research conducted in the Brazilian Atlantic Forest, and propose methods to integrate, analyze and visualize data. We found that the outcomes based on combined ecological and social research findings were, in some cases, different from those based on any of these lines of evidence alone. Indeed, the input from relatively basic social research significantly changed the outcomes of decision-making based on the results of ecological research. Results corroborate the importance and cost-effectiveness of broadening the interdisciplinary evidence base for conservation decision-making, even when social data is scarce and analytical capacity is limited.     

Expanding temporal resolution in landscape transformations: Insights from a landsat-based case study in Southern Chile

Understanding temporal and spatial dimensions of land cover dynamics is a critical factor to link ecosystem transformation to land and environmental management. The trajectory of land cover change is not a simple difference between two conditions, but a continuous process. Therefore, there is a need to integrate multiple time periods to identify slow and rapid transformations over time. We mapped land cover composition and configuration changes using time series of Landsat TM/ETM+ images (1985–2011) in Southern Chile to understand the transformation process of a temperate rainforest relict and biodiversity hotspot. Our analysis builds on 28 Landsat scenes from 1985 to 2011 that have been classified using a random forests approach. Base on the high temporal data set we quantify land cover change and fragmentation indices to fully understand landscape transformation in this area. Our results show a high deforestation process for old growth forest strongest at the beginning of the study period (1985–1986–1998–1999) followed by a progressive slowdown until 2011. Within different study periods deforestation rates were much larger than the average rate over the complete study period (0.65%), with the highest annual deforestation rate of 1.2% in 1998–1999. The deforestation resulted in a low connectivity between native forest patches. Old-growth forest was less fragmented, but was concentrated mainly in two large regions (the Andes and Coastal mountain range) with almost no connection in between. Secondary forest located in more intensively used areas was highly fragmented. Exotic forest plantation areas, one of the most important economic activities in the area, increased sevenfold (from 12,836 to 103,540 ha), especially during the first periods at the expense of shrubland, secondary forest, grassland/arable land and old grown forest. Our analysis underlines the importance of expanding temporal resolution in land cover/use change studies to guide sustainable ecosystem management strategies as increase landscape connectivity and integrate landscape planning to economic activities. The study is highlighting the key role of remote sensing in the sustainable management of human influenced ecosystems.     

Contrasting nutrient exports from a forested and an agricultural catchment in south-eastern Australia

Dissolved organic carbon (DOC) and total and inorganic nitrogen and phosphorus concentrations were determined over 3 years in headwater streams draining two adjacent catchments. The catchments are currently under different land use; pasture/grazing vs plantation forestry. The objectives of the work were to quantify C and nutrient export from these landuses and elucidate the factors regulating export. In both catchments, stream water dissolved inorganic nutrient concentrations exhibited strong seasonal variations. Concentrations were highest during runoff events in late summer and autumn and rapidly declined as discharge increased during winter and spring. The annual variation of stream water N and P concentrations indicated that these nutrients accumulated in the catchments during dry summer periods and were flushed to the streams during autumn storm events. By contrast, stream water DOC concentrations did not exhibit seasonal variation. Higher DOC and NO₃ ⁻ concentrations were observed in the stream of the forest catchment, reflecting greater input and subsequent breakdown of leaf-litter in the forest catchment. Annual export of DOC was lower from the forested catchment due to the reduced discharge from this catchment. In contrast however, annual export of nitrate was higher from the forest catchment suggesting that there was an additional NO₃ ⁻ source or reduction of a NO₃ ⁻ sink. We hypothesize that the denitrification capacity of the forested catchment has been significantly reduced as a consequence of increased evapotranspiration and subsequent decrease in streamflow and associated reduction in the near stream saturated area.     

Spatial pattern analysis in forest dynamics: deviation from power law and direction of regeneration waves

Grid-based models have been used to understand spatial heterogeneity of the vegetation height in forests and to analyze spatio-temporal dynamics of the forest regeneration process. In this report, we present two methods of identifying lattice models when spatio-temporal data are given. The first method detects directionality of regeneration waves based on the timing of local disturbance events. The second evaluates the forest pattern by recording the fraction of high and low vegetation areas at multiple spatial scales. We illustrate these methods by applying them to patterns generated using three simple stochastic lattice models: (1) two-state model, distinguishing sites with high and low vegetation, (2) three-state model, in which sites can be in an additional disturbed state, and (3) Shimagare model, which considers a continuous range of states. The combination of the two methods provides efficient means of distinguishing the models. The first method has a more direct ecological meaning, while the second is useful when forest data are limited in time.     

Hydrochory,seed banks,and regeneration dynamics along the landscape boundaries of a forested wetland

Following the environmental sieve concept, the setting in which the recruitment of Taxodium distichum occurs in, becomes increasingly restrictive from the seed to seedling stage in an impounded forested wetland. Although a wide elevational band of dispersing seed moves across the boundary of a swamp-field in the water sheet, the zone of germination is relegated to that portion of the forested wetland that draws down during the growing season. Seedling recruitment is further restricted to the uppermost zone of the winter water sheet. These patterns are likely applicable to other species of dominant swamp species, e.g., Cephalanthus occidentalis crossed the boundary of a forested wetland and abandonded field in winter flooding (November–December and November–March, respectively) in Buttonland Swamp. The elevation of the boundary was 101.3 m NGVD. While the seeds of at least 40 swamp species were dispersed across the boundary, few viable seeds were dispersed after the winter season. Kriged maps showed seeds of T. distichum and C. occidentalis dispersed in patches in the water depending on the position of the water sheet. Most species of both water- and gravity-dispersed species had a localized pattern of seed distribution (either spherical or exponential) and this indicated that seeds may not be dispersed for great distances in the swamp. Water-dispersed T. distichum and C. occidentalis had larger dispersal ranges (A ₀=225 and 195 m, respectively) than Bidens frondosa and B. discoidea (A ₀=14 and 16 m, respectively). Seed dispersal varied with season depending on the availability of seeds. In Buttonland Swamp, viable seeds typically were dispersed for T. distichum in November–June, and for C. occidentalis in November-July. Low water occurred in August 1993 and high in February 1994 (99.8 and 101.6 m NGVD, respectively). The seed banks along the landscape boundary varied in species composition according to elevation (r ² = 0.996). While the similarity of species richness between water-dispersed seeds and the seed bank at elevations that flooded (during June 1993 through May 1995) was high (10–17%), it was low between water-dispersed seeds and the seed bank at elevations that did not flood (5%). T. distichum seeds had a short germination window in that seeds germinated within a year following their production in zones that were flooded in the winter followed by drawdown during the next growing season. After 1 year, less than 5% of the T. distichum seeds remained viable on the surface of the soil. Germination of T. distichum was confined to specific elevations (above 99.3 but below 101.6 m NGVD) during this study with 4.1% of the seedlings surviving for more than 2 years at a mean of 101.4 m NGVD. All seedlings below this elevation died. To maximize natural regeneration along the boundaries of swamps in abandoned farm fields targeted for restoration, this study suggests a flood pulse regime consisting of high water in the winter to maximize dispersal of live seeds followed by low water in the summer to facilitate seed germination and seedling recruitment. Hydrologic restoration could assist in the natural recovery of damaged wetlands if a seed source exists nearby.     

Spatial and temporal deforestation dynamics in protected and unprotected dry forests: a case study from Myanmar (Burma)

Tropical dry forests are more threatened, less protected and especially susceptible to deforestation. However, most deforestation research focuses on tropical rain forests. We analyzed spatial and temporal changes in land cover from 1972 through 2005 at Chatthin Wildlife Sanctuary (CWS), a tropical dry forest in Myanmar (Burma). CWS is one of the largest protected patches of tropical dry forest in Southeast Asia and supports over half the remaining wild population of the endangered Eld’s deer. Between 1973 and 2005, 62% of forest was lost at an annual rate of 1.86% in the area, while forest loss inside CWS was only 16% (0.45% annually). Based on trends found during our study period, dry forests outside CWS would not persist beyond 2019, while forests inside CWS would persist for at least another 100 years. Analysis of temporal deforestation patterns indicates the highest rate of loss occurred between 1992 and 2001. Conversion to agriculture, shifting agriculture, and flooding from a hydro-electric development were the main deforestation drivers. Fragmentation was also severe, halving the area of suitable Eld’s deer habitat between 1973 and 2001, and increasing its isolation. CWS protection efforts were effective in reducing deforestation rates, although deforestation effects extended up to 2 km into the sanctuary. Establishing new protected areas for dry forests and finding ways to mitigate human impacts on existing forests are both needed to protect remaining dry forests and the species they support.     

The integration of crop rotation and tillage practices in the assessment of ecosystem services provision at the regional scale

The provision of ecosystem services at the landscape level can be significantly influenced by land management practices. Within an agriculturally dominated case study area in Saxony, Germany, a more detailed land use classification, which includes differentiated information on agricultural management practices, was utilized within the raster-based planning support tool GISCAME. “Management” refers to typical, regional crop rotations and soil tillage practices.The focus of this research was based on an indicator-based approach to assess ecosystem services and the development of land use change (LUC) and land management change (LMC) scenarios. The EuroMaps Land Cover data set was specifically developed for the case study and included remote sensing information for the general land use classification and terrestrial mapping information. Furthermore, statistical data on detailed regional agricultural land management were included. The raster-based planning support tool GISCAME was then used to simulate scenarios and visualize results. The LUC and LMC scenarios showed that the more detailed land use classification provided better output for the prioritization of planning alternatives. Further it enabled a refined assessment of the provisioning services (i) food and fodder provision, (ii) biomass provision, the regulation services, (iii) soil erosion protection, (iv) drought risk regulation, (v) flood regulation, (vi) returns from land-based production (i.e. the market value of biomass provision), and (vii) ecological integrity. The results of this study support the view that the application of improved management measures, such as conservation tillage, can significantly enhance the provision of ecosystem services (e.g. soil erosion protection and drought risk regulation) at the landscape level. The study also indicates that a combination of strategic LUC, such as afforestation and LMC, might be an effective way to enhance regulating services with acceptable trade-offs regarding provisioning services. Our approach presents a refined foundation for ecosystem services assessment, which is designed to better support regional planning and the provision of information to non-experts in the participatory processes. For transfer into other regions, standardized land use and land management classification will have to be defined.     

The influence of the ecological characteristics of phytocoenoses on the percentage proportions of zoogeographical elements in the malacocoenoses of land snails (Mollusca: Gastropoda terrestria)

The influence of 11 forest phytocoenoses in a single area (the Medvednica Mountain in north-western Croatia) on the composition of the zoogeographical elements of the land malacofauna was analysed. It was established that malacocoenoses in different plant associations of the same phytogeographical and zoogeographical area have different compositions in respect to the zoogeographical elements of the land snail fauna. Zoogeographical elements located on borders of the range display the widest divergences in their percentage representation in the malacocoenoses of the forest phytocoenoses of a single area. This is due to varying ecological conditions in the phytocoenoses under investigation.Abbreviations as. = association - subas.= subassociation     

Primary production, nutrient dynamics, and accretion of a coastal freshwater forested wetland assimilation system in Louisiana

This study reports on the response of a tidal, freshwater forested wetland ecosystem to long-term input of secondarily treated municipal effluent from the City of Mandeville, LA. Measurements of hydrology, nutrients, and aboveground net primary productivity were made from September 1998 through March 2002. Accretion measurements were made in October 2000 and October 2004. The major hydrologic inputs to the system were the effluent, precipitation, and back water flooding from Lake Pontchartrain. Nutrient levels were generally low except in the immediate vicinity of the outfall. Mean net primary production of the freshwater forest system was significantly higher downstream of the effluent discharge (1202 g m⁻² yr⁻¹) compared to the control site (799 g m⁻² yr⁻¹). Downstream of the outfall, accretion rates were double the rate of relative sea level rise in the area. Removal efficiencies of N and P were as high as 75% and 95%, respectively. The relatively constant flow of secondarily treated municipal effluent buffered the downstream area from salinity intrusion during a region-wide drought. Re-direction of nutrient-enhanced effluents from open water bodies to wetland ecosystems can maintain plant productivity, sequester carbon, and maintain coastal wetland elevations in response to sea-level rise in addition to improving overall surface water quality, reducing energy use, and increasing financial savings.     

Implications of seasonal variation in nitrate export from forested ecosystems: a review from the hydrological perspective of ecosystem dynamics

In recent decades, the seasonal variation in NO₃ ^? discharge from forest ecosystems has been used increasingly by ecologists and hydrologists as a diagnostic indicator of the nutrient status of ecosystems. Major factors underlying the seasonal patterns of stream NO₃ ^? concentration include seasonal variations in (1) ecosystem nutrient demand, (2) solute transport capability of the hydrological condition, and (3) in-stream nutrient usage and supply. In this article I show how case studies have helped elucidate the dominant controlling factors by comparing data from Japanese catchments with previously compiled data from studies in North America and Europe. Moreover, I explain the different influences that hydrological and biogeochemical controls exert in regions with rainy (Japan) and dry (northeastern United States and Europe) summers. The seasonal variation in hydrological conditions is the predominant controlling factor in Japanese forests, whereas nutrient demand may predominate in the northeastern United States and Europe. I emphasize the importance of comparing seasonal patterns among regions with differing climates to obtain more universal explanations of seasonal variations in NO₃ ^?-related biogeochemical and hydrological dynamics in a forest ecosystem. In addition, multi-scale investigations will be needed to provide insight into the relative contributions of hillslope biogeochemical effects and in-stream biological activities.     

Improving the assessment of species compositional dissimilarity in a priori ecological classifications: evaluating map scale,sampling intensity and improvement in a hierarchical classification

Question: Can species compositional dissimilarity analyses be used to assess and improve the representation of biodiversity patterns in a priori ecological classifications? Location: The case study examined the northern‐half of the South‐east Queensland Bioregion, eastern Australia. Methods: Site‐based floristic presence–absence data were used to construct species dissimilarity matrices (Kulczynski metric) for three levels of Queensland's bioregional hierarchy – subregions (1:500 000 scale), land zones (1:250 000 scale) and regional ecosystems (1:100 000 scale). Within‐ and between‐class dissimilarities were compiled for each level to elucidate species compositional patterns. Randomized subsampling was used to determine the minimum site sampling intensity for each hierarchy level, and the effects of lumping and splitting illustrated for several classes. Results: Consistent dissimilarity estimates were obtained with five or more sites per regional ecosystem, 10 or more sites per land zone, and more than 15 sites per subregion. On average, subregions represented 4% dissimilarity in floristic composition, land zones approximately 10%, and regional ecosystems over 19%. Splitting classes with a low dissimilarity increased dissimilarity levels closer to average, while merging ecologically similar classes with high dissimilarities reduced dissimilarity levels closer to average levels. Conclusions: This approach demonstrates a robust and repeatable means of analysing species compositional dissimilarity, determining site sampling requirements for classifications and guiding decisions about ‘lumping’ or ‘splitting’ of classes. This will allow more informed decisions on selecting and improving classifications and map scales in an ecologically and statistically robust manner.     

Species richness in agroecosystems: the effect of landscape, habitat and farm management

It has been suggested that biodiversity in agroecosystems depends on both landscape heterogeneity and farm management, but at the same time, studies of biodiversity in relation to both landscape variables and farm management are rare. We investigated the species richness of plants, butterflies, carabids, rove beetles and the diversity of spiders in cereal fields, leys (grass and clover crop) and semi-natural pastures at 16 farms in Central East Sweden. The farms were divided into eight pairs of one conventional and one organic farm to enable us to separate the effects of landscape and farm management on biodiversity. The pairing was based on land use, location, and landscape features. Species richness of different taxonomic groups was generally not correlated. There were no differences in species richness between the farming systems, except for carabids that had higher numbers of species on conventional farms. The species richness generally increased with landscape heterogeneity on a farm scale. Habitat type had a major effect on the species richness for most groups, with most species found in pastures and leys. The correlations between species richness and landscape variables on a farm scale, and not on a scale of multiple farms, identify farmers as the important decision-maker in conservation issues for these taxonomic groups. We discuss the role of species richness of pests' natural enemies for biological control and conservation strategies of the more common species in the agricultural landscape.     

Linking species distribution and territorial planning to the management of the endangered Gonopterodendron sarmientoi in native forests of the Chaco region,Argentina

For management and conservation strategies in the long term is necessary to know the species distribution and main biophysical aspects that determine the structure and dynamics of the forest. The aim of this work was to determine the potential and current spatial distribution of Gonopterodendron sarmientoi, an emblematic and endangered tree species of the Dry Chaco. A further aim was to superimpose the distribution of G. sarmientoi, with the zonation in the current Territorial Planning of Native Forests (OTBN, its acronym in Spanish) to provide basic information for conservation and management of the species. For this, a Maxent model was developed to quantify the relationship between G. sarmientoi occurrence and key environmental variables (including water, topography, and climate as a variables). G. sarmientoi’s habitat was mainly influenced by precipitation variables, and secondarily by temperature variables. Considering the OTBN defined by the local forest authority, of the current area of G. sarmientoi (2,477,009 ha), the majority (57.9%) corresponded to the yellow category (forest areas with medium conservation value) and only 10.6% to the red category (high conservation value). It is important to note that around 600,686 ha (24.3%) of native forest with G. sarmientoi is in the green category (low conservation value) subject to change in land use, and 178,107 ha was uncategorized forest (7.2%). For effective management and conservation strategies, the current habitat distribution map of G. sarmientoi provides decision-makers an opportunity to review and adjust the native forests zoning at a provincial scale within the framework of the OTBN, mainly the green category (legal deforestation) with the occurrence of the endangered G. sarmientoi.     

Consistent pattern of habitat and species selection by post-dispersal seed predators in a Mediterranean mosaic landscape

There is still little information on effects of habitat degradation on post-dispersal seed predation at the landscape scale. The aim of this study was to determine the influence of habitat degradation and seed species on the variability of post-dispersal seed-predation rate. Experimental seed removal was investigated in six Mediterranean woody plant species, four trees (Pinus sylvestris, Quercus ilex, Acer opalus ssp. granatense, and Sorbus aria) and two shrubs (Berberis vulgaris and Crataegus monogyna), in an extensively used mosaic landscape on the Sierra Nevada massif (SE Spain). Seed depots were distributed over 2 years in five differently degraded landscape units, each one with three plots: shrubland; native forest; and dense, cleared and fenced reforestation stands. Predation was the highest in native forest, shrubland, and fenced reforestation, and the lowest in dense and cleared reforestation stands, being partially due to a positive correlation between shrub cover and post-dispersal seed predation. However, the main factors driving post-dispersal seed predation were intrinsic to seeds, as species preference explained most of the variance in our model for predation. The plant-species ranking was Quercus > Pinus > Sorbus > Berberis > Acer > Crataegus, the dominant tree species being the most depredated. These findings are novel because they suggest for the first time that species-selection patterns by post-dispersal seed predators tended to remain constant through both study years in all habitats comprising a mosaic landscape, whether native forest, reforestation stands or successional shrubland.