Exotic Forest Plantations Research Articles

The relative importance of local versus regional habitat structure variation on the abundance of two generalist mutualists along a forest disturbance gradient

Mutualistic interactions are key to biodiversity generation and maintenance, being pollination and seed dispersal interactions essential for plant reproduction. However, anthropogenic habitat disturbance can alter these interactions. We studied the regional and local effects of habitat disturbance on two generalist mutualist animals of southern Chile temperate rainforests: the hummingbird Sephanoides sephaniodes and the marsupial Dromiciops gliroides, which perform key roles as pollinator and seed disperser, respectively. We sampled 12 sites corresponding to four disturbance conditions (mature native forest, secondary forest, native forest under selective logging, and exotic forest plantations) in which we estimated the number of S. sephaniodes and D. gliroides records (as a proxy of relative abundance) using camera traps. We measured seven habitat structure variables at each site, known to influence their occurrence. Specifically, we examined S. sephaniodes and D. gliroides abundance variation at (i) a regional scale (among disturbance conditions) and (ii) at a local scale (among sampling sites). Dromiciops gliroides abundance decreased as disturbance increased, but S. sephaniodes abundance was highly variable. At the local scale, S. sephaniodes and D. gliroides abundances were largely variable among sites, influenced by habitat structural features, such as bamboo and shrub cover and woody debris. Our results show that although habitat disturbance may influence mutualist abundances, they can tolerate disturbance if minimum structure and resource requirements are met, but respond idiosyncratically to local conditions. Examining local-scale variability may provide valuable information on ecological processes, which often goes unnoticed when local sites are considered as replicates in landscape-level studies.

Exploring freshwater stream bacterial communities as indicators of land use intensity

BackgroundStream ecosystems comprise complex interactions among biological communities and their physicochemical surroundings, contributing to their overall ecological health. Despite this, many monitoring programs ignore changes in the bacterial communities that are the base of food webs in streams, often focusing on stream physicochemical assessments or macroinvertebrate community diversity instead. We used 16S rRNA gene sequencing to assess bacterial community compositions within 600 New Zealand stream biofilm samples from 204 sites within a 6-week period (February–March 2010). Sites were either dominated by indigenous forests, exotic plantation forests, horticulture, or pastoral grasslands in the upstream catchment. We sought to predict each site’s catchment land use and environmental conditions based on the composition of the stream bacterial communities.ResultsRandom forest modelling allowed us to use bacterial community composition to predict upstream catchment land use with 65% accuracy; urban sites were correctly assigned 90% of the time. Despite the variation inherent when sampling across a ~ 1000-km distance, bacterial community data could correctly differentiate undisturbed sites, grouped by their dominant environmental properties, with 75% accuracy. The positive correlations between actual values and those predicted by the models built using the stream biofilm bacterial data ranged from weak (average log N concentration in the stream water, R2 = 0.02) to strong (annual mean air temperature, R2 = 0.69).ConclusionsFreshwater bacterial community data provide useful insights into land use impacts on stream ecosystems; they may be used as an additional measure to screen stream catchment attributes.

Land use intensity is a major driver of soil microbial and carbon cycling across an agricultural landscape

Soil carbon (C) storage is a critical ecosystem function that underpins human health and well-being. The acceleration of human-driven land use change, such as agricultural intensification, is a major driver of soil C loss globally. Developing sustainable land use practices that enhance agricultural productivity whilst protecting essential ecosystem functions such as soil C storage is vital. The soil microbiome has a critical role in regulating soil biogeochemical cycling processes, including soil C cycling. Examining the impacts of land use intensity on the soil microbiome enables us to assess the potential effects on long-term soil C stocks. Using metagenomic DNA sequencing and phospholipid fatty acid analysis, we investigated differences in the activity, diversity, and function of the soil microbiome associated with five contrasting land uses across an agricultural landscape. The land uses covered a gradient of disturbance intensities and included remnant native forest, regenerating native bush, exotic plantation forest, dryland pasture, and irrigated pasture. We identified pronounced differences in the soil microbiome associated with each land use, including the diversity and abundance of microbial C and nitrogen (N) cycling genes. Notably, intensive agricultural land uses had a significantly higher diversity and abundance of microbial C-degrading genes, whilst land uses of remnant native forest had the lowest diversity and abundance of microbial C-degrading genes. Our findings suggest that intensive agricultural land use may increase the functional potential of the soil microbiome to mineralize soil C, potentially resulting in a greater loss of soil C as respired CO2 into the atmosphere. This research may be used to support the development of sustainable management practices that promote the persistence of soil C across agricultural landscapes, such as the protection of remnant native forest fragments and greater incorporation of regenerating native vegetation.

Comparing diversity of the terrestrial mammal communities inhabiting native forests and exotic plantations in southern Chile

The mammal community of the Coastal Range of southern Chile has been little studied even though they inhabit an environment under severe threats due to anthropic disturbance. During the spring-summer seasons of 2020–2021 and 2021–2022, we characterized the communities of wild terrestrial mammals in a native forest (NF) and an exotic plantation of Eucalyptus (PL) of the Coastal Range of Osorno province by phototrapping. We used 1,060 camera-trap days in the NF and 960 camera-trap days in the PL to explore the effect of habitat type on wild mammal diversity in two localities (L-1 and L-2). We quantified the species richness, abundance, community similarity and daily distribution of mammal communities. Species richness was higher in the NF (7–8 spp) than in the PL (3–4 spp). Two community similarity index (CSI) was significantly higher between native forests (CSI = 0.728 ± 0.088) than between Eucalyptus plantations (CSI = 0.211 ± 0.097) (95% CI). Mean abundance was also higher in the NF than in the PL (L-1: 0.011 vs. 0.004 occurrence/camera-trap day (OCT); L-2: 0.008 vs. 0.004 OCT). In L-1, the most abundant mammals in the NF were Leopardus guigna (45.3% of relative occurrence (RO)) and Pudu puda (18.9% RO), and in the PL, they were Lycalopex culpaeus (50% RO) and L. guigna (37.5% RO). In L-2, the highest abundances in the NF were for P. puda (34.5% RO) and Puma concolor (27.6% RO), while in the PL, P. puda was predominant (66.7% RO). In NF of both localities, 22.2% of melanic L. guigna individuals were observed. The highest frequency of occurrences in both locations was between 12:00 and 23:59 hours, with 60% and 76.9% of detections, respectively. The species richness found in native forest is in accordance with studies carried out in other temperate rainforests of southern Chile. In addition, native forests support a richer and more similar community of terrestrial mammals than exotic forest plantations, which indicates that native forests are the main habitat for most mammals detected and that exotic plantations function as a complementary habitat for some species.

Identifying a green infrastructure to prioritise areas for restoration to enhance the landscape connectivity and the provision of ecosystem services

IntroductionHabitat fragmentation is one of the major causes of the loss of biodiversity that our planet is experiencing. This has affected the ecosystems functioning and, consequently, the provision of ecosystem services (ES). Therefore, the European Commission, in a 2013 communication, established the concept of Green Infrastructure (GI), which is a strategically planned network of multifunctional areas with the aim of protecting biodiversity and ES supply, as well as improving ecological connectivity. Ecological restoration is an essential element to achieve the objectives of the GI, which if well targeted, could reverse widespread ecosystem degradation and improve landscape connectivity.ObjectiveIn this study, we propose a methodology to prioritise areas to restore by identifying a GI in the Urdaibai Biosphere Reserve (UBR), in the north of the Iberian Peninsula, where forest plantations of exotic species abound.MethodsIn order to identify the elements of the GI (core areas and corridors) we integrated a multispecies approach based on the movement of key species and an ES-based approach based on multifunctionality. Subsequently, to prioritise areas to restore we identified sectors in the GI, where connectivity is particularly vulnerable (pinch points) using the circuit theory. Thus, forest plantations around the pinch points were prioritised for a future restoration plans depending on their aim: (1) Improve corridors of high importance and low quality for the multispecies approach (2) Improve corridors of high importance and low quality for the ES-based approach, and (3) Improve the connectivity of the GI for the species movement.ResultsThe resultant GI included 36% of the UBR surface. We identified 34 pinch points for the corridors of the three especies in the multispecies approach and 64 in the ES-based approach. We prioritised 149 ha of exotic forest plantations around the pinch points to convert into native forest in order to improve the corridors and 167 ha to improve GI connectivity.ConclusionThis information could be useful for organizations and institutions carrying out restoration actions for the recovering of native forests in the territory.

A preliminary study of kea (Nestor notabilis) habitat use and diet in plantation forests of Nelson, New Zealand

ABSTRACT Kea (Nestor notabilis) are nationally endangered, large endemic parrots in the South Island of New Zealand. In recent years, anecdotal evidence and sightings from forestry workers have confirmed that kea use exotic plantation forests in the Nelson/Tasman region. We documented kea habitat use and movements in Nelson plantation and neighbouring native forests. GPS-VHF units were used to track kea movements through the plantation-native forest matrix. All birds tracked in this study spent a notable proportion of their time in plantation forests, which included feeding, roosting and nesting. Feeding observations and faecal analysis were used to determine kea diet in plantation forests. In the summer, Pinus radiata seeds were commonly observed being eaten by kea, as was cambium tissue stripped off newly harvested Pseudotsuga menziesii logs. Of the items identified through faecal analysis, the most common group was invertebrates. This research was a preliminary study of kea activity in plantation forests and suggests the value of extending research to cover at least a full calendar year to record seasonal patterns in kea diet, habitat use and movements in and out of this habitat type.

High vulnerability of coastal wetlands in Chile at multiple scales derived from climate change, urbanization, and exotic forest plantations

Coastal wetlands are considered one of the most vulnerable ecosystems worldwide; the ecosystem services they provide and the conservation of their biodiversity are threatened. Despite the high ecological and socioenvironmental value of coastal wetlands, regional and national vulnerability assessments are scarce. In this study we aimed to assess the vulnerability of coastal wetlands in Chile from 18°S to 42°S (n = 757) under a multiscale approach that included drivers associated with climate change and land cover change. We assessed multiple drivers of vulnerability at three spatial scales (10 m, 100 m, and 500 m) by analyzing multiple remote sensing data (16 variables) on land cover change, wildfires, climatic variables, vegetation functional properties, water surface and importance for biodiversity. We constructed a multifactorial vulnerability index based on the variables analyzed, which provided a map of coastal wetland vulnerability. Then we explored the main drivers associated with the vulnerability of each coastal wetland by performing a Principal Components Analysis with Agglomerative Hierarchical Clustering, which allowed us to group coastal wetlands according to the drivers analyzed. We found that 42.6 ± 9.2 % of the coastal wetlands evaluated have high or very high vulnerability, with higher vulnerability at the 500 m scale (51.4 %). We identified four groups of coastal wetlands: two located in central Chile, mainly affected by climate change-associated drivers (41.9 ± 2.1 %), and one in central Chile which is affected by land cover change (52.8 ± 6.2 %); the latter has a lower vulnerability level. The most vulnerable coastal wetlands were located in central Chile. Our results present novel findings about the current vulnerability of coastal wetlands, which could be validated by governmental institutions in field campaigns. Finally, we believe that our methodological approach could be useful to generate similar assessments in other world zones.

Occupancy patterns of two contrasting carnivores in an industrial forest mosaic

Normally, industrial forest landscapes are mosaics of different exotic and native vegetation patches, and, depending on their structural and functional diversity, they may be able to support potentially important biodiversity. In Central Chile, there are 3.1 million hectares of exotic forest plantations, and these environments are included as habitat, among others, of two contrasting carnivores: the generalist culpeo fox (Lycalopex culpaeus) and the kodkod (Leopardus guigna), a forest specialist cat. For this study, we sampled a large area (∼350 km2) in the coastal range of Central Chile with camera traps (n = 500) for three consecutive years to observe the summer occupancy patterns of these two carnivores. We used single season occupancy models with covariates at landscape and local scales. The main results showed that, for the culpeo fox, the proportion of harvested area had a positive influence on its occupation, whereas for the kodkod the proportion of bare soil and leaf litter had a negative and positive influence, respectively. Since both species occupy the landscape mosaic created by the forestry industry, it would be valuable to integrate the observed occupancy patterns into conservation plans at both local and landscape levels for these species.

Industrial forestry negatively affects small-farms honey production in south-central Chile: evidence from a landscape scale

Land use and cover change have a high influence on bee species, where honey bees (Apis mellifera) could be affected in terms of resources, dispersal, and habitat. However, the influence of landscape context on honey productivity has been scarcely explored in comparison with population parameters, which is an essential topic for the economic development of rural communities based on apiculture. Here, we tested the hypothesis if honey production decreases with the increase of exotic forest plantations in the landscape as the cover of native forest decreases, vegetation and soils become increasingly degraded. We compiled data on honey productivity for two years (2018 and 2019) of small-scale honey production in 17 landscapes of 1 km radii (Curanilahue state in south-central Chile). Then, the landscapes were characterized by using remote sensing techniques, including biophysical and compositional landscape variables. Finally, Generalized Linear Mixed Models were implemented to explore the relationship between landscape variables and honey productivity. We identified a positive relationship between honey productivity with built cover and grassland cover. On the other hand, a negative relationship was found between honey production and net primary production, exotic forest plantations, and tree senescence index. Our results provide new insights into the landscape-scale drivers of hive productivity in rural landscapes of south-central Chile.

Unraveling the Differences in Landcover Patterns in High Mountains and Low Mountain Environments within the Valdivian Temperate Rainforest Biome in Chile

The Valdivian temperate rainforest (VTR) is a biome on the South American continent with high endemism that has experienced an intensive land-cover change in recent decades due to the expansion of agriculture, plantations of introduced forests, and urban growth. Today, the biome hosts key parts of the country’s agricultural and forestry industries. Previous studies focused on quantifying native forest and plantation cover area and exotic forest plantation area, among others. However, the importance of mountain areas as refuge of native forest in Chile remains unexplored. The aim of this research is to highlight the role of latitude and slope on land cover in the VTR. A new methodological approach was used combining global classified datasets. Our results indicate that high mountain areas are the core location of the remaining primary forests and endemism whereas low mountain areas are dominated by exotic forest plantations. Between 40–48° S (The Los Ríos, Los Lagos, and Aysén Regions and high-mountain areas), in general, serve as a natural reservoir where human-induced land-cover change has not occurred on a large scale. Most public and private conservation areas are in high mountain areas, whereas low mountain areas and plain areas lack conservation schemes and are more prone to land cover change towards forestry. Considering geomorphological features in land cover change analysis can reveal interesting new perspectives in this research area.

Conversion of Andean montane forest to exotic forest plantation modifies soil physicochemical properties in the buffer zone of Ecuador's Podocarpus National Park

Conversion of Andean montane forest to exotic forest plantation modifies soil physicochemical properties in the buffer zone of Ecuador's Podocarpus National Park

Hydrophysical characteristics in water-repellent tropical Eucalyptus, Pine, and Casuarina plantation forest soils

Abstract Soil water repellency (SWR) reduces the rates of wetting in dry soils and is known to interfere with water movement into as well as within the soils. The objective of this study was to investigate the hydrophysical characteristics of three water-repellent tropical exotic plantation forest soils in wet and dry seasons. The study sites were Eucalyptus grandis (EG), Pinus caribaea (PC), and Casuarina equisetifolia (CE) plantation forest soils located in the up-country intermediate zone (EG and PC), and low-country dry zone (CE). Field experiments were conducted to measure the infiltration rate, unsaturated hydraulic conductivity (k), water sorptivity (S W). Laboratory experiments were conducted to measure the potential SWR and water entry value (h we). All three soils showed higher SWR in the dry season, where CE soils showed the highest. The EG soils showed the highest SWR in the wet season. Although SWR in all soils decreased with increasing depth in the wet season, only CE soils showed a significant decrease in SWR with soil depth in the dry season. Compared with the wet season, the k(–1 cm) was lower and h we was higher in the dry season. However, S W did not show a significant difference between wet and dry seasons. Initial infiltration rate and k(–1 cm) showed a negative correlation with contact angle in all three soils. Soils showed positive linear correlations between k(–1 cm) and S W, and negative linear correlations between S W and h we showing that surface water absorption is related to both subsurface unsaturated water flow and surface water entry pressure. It was clear that the water entry into soils and the subsurface water flow were hindered by the SWR. High water entry values in the dry season predict high potentials for intensified surface runoff and topsoil erosion. Future research will be required on the interactions between soil biology and soil properties such as pore structure that would influence water flow into and within soils.

Linking sedimentological and spatial analysis to assess the impact of the forestry industry on soil loss: The case of Lanalhue Basin, Chile

Soil loss has become one of the main problems associated with global change over the last decades. New assessments are needed in order to improve our understanding of the real impacts of human productive activities on the natural dynamics linked to erosion in lake basins. We analyzed the recent and historical dynamics of soil loss in a coastal lake basin of central Chile (Lanalhue lake), evaluating land use impacts and proposing management changes to control erosion and restore the soil. We implemented two approaches: A) Using a high-resolution sedimentological proxy and a high-accuracy chronology of cores to determine the sediment accumulation rate, organic/inorganic matter and granulometry for the last 120 years; and B) applying the Universal Soil Loss Equation to estimate erosion of soil from hills during the last 32 years, considering a combination of satellite, climate, soil, and land-cover topographic data. We found that the sedimentation rates, as well as the concentration of organic matter in lake sediments, were relatively constant from 1900 to 1950; after that, they experienced a significant increase. The same pattern of rapid increase was found for sand content. We found that erosion during the last 30 years has been high and constant, especially in bare soil (mainly clear-cutting areas) and exotic forest plantations. Erosion has been significantly higher within exotic forest plantations, reaching 31 ton/ha/yr in clear-cutting areas. Three industrial forestry companies accounted for 61.5% of the basin surface where urgent erosion control is needed. Our findings support the indication that industrial forestry is the main activity affecting erosion dynamics in the basin; secondarily, earthquakes have been important modulators of the sediment dynamics in Lanalhue during these last 120 years.

Effect of Forest Cover on Raptor Abundance in Exotic Forest Plantations in Chile

Habitat specialists, such as forest raptors, are generally more likely to suffer from the impacts of large-scale forestry. One of the most characteristic and controversial aspects of many industrial plantation systems is the use of clearcutting as a harvesting method, which generates a mosaic of highly contrasting land cover types, such as wooded areas adjacent to zones practically devoid of vegetation. We explored the effect of forest cover on the abundance of habitat-generalist and forest-specialist raptors in South-central Chile. During the 2016 to 2018 breeding seasons, we conducted 584 playback surveys at 149 sampling points centred on 3×3km plots within 9×9km squares. The Rufous-legged Owl Strix rufipes, a forest specialist, showed a positive relationship with forest cover at the local scale. However, we found no significant relationships for other forest specialists in this study. Most habitat-generalist species showed a negative or non-linear relationship with forest cover, with greater species abundances observed in landscapes with intermediate levels of forest and open areas. Interestingly, the models with the highest statistical support included total forest cover (native forest + plantations) as a predictor, suggesting that the habitat-generalist species did not significantly discriminate between natural and artificial forests. Our results show that both generalist and forest-specialist raptors can use landscapes dominated by exotic plantations in South-central Chile.—Santander, F., Alvarado O., S. & Estades, C.F. (2021). Effect of forest cover on raptor abundance in exotic forest plantations in Chile. Ardeola, 68: 391-408.

Expanding Exotic Forest Plantations and Declining Rural Populations in La Araucanía, Chile

Chile has embraced the expansion of monoculture forest plantations of exotic Monterey pine and eucalyptus as part of its development strategy. While forestry is considered financially successful and meets sustainability objectives, the increase in forest plantations across southern Chile has received harsh critiques for exacerbating conflict over Indigenous land rights, producing negative environmental outcomes, and increasing poverty and inequality. There are also claims that forest plantation expansion has led to an abandonment of the countryside. Migration is viewed as a result of the socioeconomic challenges that forest plantations produce at the local level; however, the linkages have not been explored. We examine the linkages between forest plantations and migration through two questions: Is there a relationship between forest plantation cover change and out-migration from rural areas? If so, what are the factors that explain this process? We use a difference-in-differences method analyzing panel data from the Chilean census and from CONAF, the Chilean National Forest Corporation, complemented by interviews, mapping workshops, and focus groups to answer these questions. Results indicate a statistically significant relationship between expanding forest plantations and population decline in rural areas. Qualitative data show that this expansion led to displacement of residents, declines in employment opportunities, and agriculture difficulties.

An Analysis of the Impact of Forest Policy on Rural Areas of Chile

The relationship between the forest sector and the well-being of people that depend on it for their economic livelihoods in rural areas is of strong interest in forest policy. In this sense, Chile has developed a forest policy that has had positive impacts, particularly on economic and productive aspects, but also negative impacts, such as the reduction of natural forest area, biodiversity, and provision of ecosystem services, as well as the increase in social conflicts and land abandonment. However, there are few studies that have evaluated the impacts of forest policy on rural population and development of the territory. Therefore, the objective of this research is to evaluate the impacts of Chilean forest policy on rural communities, particularly in terms of demographic variables and indicators of community well-being. The study area corresponds to the Bio Bio and Ñuble Regions (Chile), and the analysis includes productive, demographic, socioeconomic, and educational characteristics of population. The results show that the forestry policy implemented was able to generate a significant increase in the proportion of forest area. However, when this increase is mainly of the type of exotic forest plantations, it is associated with a demographic and socio-economic detriment of the population in some counties of the study area.

Remote sensing data for calibrating hydrologic modeling: Hydrological impacts of land use change of the Reventado river sub-basin, Costa Rica

The “Ecological rehabilitation pilot plan of the Irazú Volcano National Park – Prusia Sector” intends to determine an ecological rehabilitation plan for current 54-year unmanaged exotic forest plantation. This study aims to determine water balance impacts on land cover changes over the Reventado river sub-basin. Thus, three scenarios were considered: Current (current cover conditions), Pasture (exotic forest plantations converted to pasture) and Forest (exotic forest plantations to natural forest). No field data was available for calibration; therefore MODIS16A2 product was used to calibrate evapotranspiration from hydrologic modeling using SWAT. An analysis was performed to determine if estimates vary using two models: 1) parameterized but non-calibrated approach(PNCA), and 2) parameterized and calibrated approach (PCA). Overall, using MODIS16A2 for calibration was satisfactory, showing statistically significant differences in ET, PERC, SURQ and GWQ. The PCA was then used for estimating the impact on water balance variables due to land cover change scenarios –previously mentioned. Slightly differences between Current and Forest scenarios were perceived, whereas Pasture showed 5 % annual increment in surface runoff and 3 % annual decrement of ground water contribution to stream. Thus, careful wood extraction and rehabilitation planning is needed in order to assure low impacts in the hydrological behavior of the sub-basin.

Using soil bacterial communities to predict physico-chemical variables and soil quality

BackgroundSoil ecosystems consist of complex interactions between biological communities and physico-chemical variables, all of which contribute to the overall quality of soils. Despite this, changes in bacterial communities are ignored by most soil monitoring programs, which are crucial to ensure the sustainability of land management practices. We applied 16S rRNA gene sequencing to determine the bacterial community composition of over 3000 soil samples from 606 sites in New Zealand. Sites were classified as indigenous forests, exotic forest plantations, horticulture, or pastoral grasslands; soil physico-chemical variables related to soil quality were also collected. The composition of soil bacterial communities was then used to predict the land use and soil physico-chemical variables of each site.ResultsSoil bacterial community composition was strongly linked to land use, to the extent where it could correctly determine the type of land use with 85% accuracy. Despite the inherent variation introduced by sampling across ~ 1300 km distance gradient, the bacterial communities could also be used to differentiate sites grouped by key physico-chemical properties with up to 83% accuracy. Further, individual soil variables such as soil pH, nutrient concentrations and bulk density could be predicted; the correlations between predicted and true values ranged from weak (R2 value = 0.35) to strong (R2 value = 0.79). These predictions were accurate enough to allow bacterial communities to assign the correct soil quality scores with 50–95% accuracy.ConclusionsThe inclusion of biological information when monitoring soil quality is crucial if we wish to gain a better, more accurate understanding of how land management impacts the soil ecosystem. We have shown that soil bacterial communities can provide biologically relevant insights on the impacts of land use on soil ecosystems. Furthermore, their ability to indicate changes in individual soil parameters shows that analysing bacterial DNA data can be used to screen soil quality.ByKu94ww1-1K9vBDz2Q4_dVideo

Soil microbial diversity in adjacent forest systems - contrasting native, old growth kauri (Agathis australis) forest with exotic pine (Pinus radiata) plantation forest.

ABSTRACTGlobally, the conversion of primary forests to plantations and agricultural landscapes is a common land use change. Kauri (Agathis australis) is one of the most heavily impacted indigenous tree species of New Zealand with <1% of primary forest remaining as fragments adjacent to pastoral farming and exotic forest plantations. By contrasting two forest systems, we investigated if the fragmentation of kauri forests and introduction of pine plantations (Pinus radiata) are significantly impacting the diversity and composition of soil microbial communities across Waipoua kauri forest, New Zealand. Using next generation based 16S rRNA and ITS gene region sequencing, we identified that fungal and bacterial community composition significantly differed between kauri and pine forest soils. However, fungal communities displayed the largest differences in diversity and composition. This research revealed significant shifts in the soil microbial communities surrounding remnant kauri fragments, including the loss of microbial taxa with functions in disease suppression and plant health. Kauri dieback disease, caused by Phytophthora agathidicida, currently threatens the kauri forest ecosystem. Results from this research highlight the need for further investigations into how changes to soil microbial diversity surrounding remnant kauri fragments impact tree health and disease expression.

Landscape-scale management of exotic forest plantations: synergy between deadwood and clear-cutting synchrony modulates saproxylic beetle diversity

Although saproxylic beetles use deadwood in industrial exotic forest plantations, deadwood and historical land use patterns may interact among each other making difficult the implementation sustainable management intended to conserve saproxylic beetle diversity. We assessed the additive and interactive effects of deadwood and landscape-scale variables on alpha (α) and gamma (γ) diversity of saproxylic beetles. We installed 1034 traps in 80 stands of pine/eucalyptus plantations, clear-cuts and native forest distributed in 29 1-km radius landscape units. Deadwood amount/diversity and composition (native vs. exotic) were estimated for each habitat. A 14-year image time series was used to estimate the cover of native forest and the temporal coefficient of variation of clear-cut cover, CV(CC), an indicator of how extensive clear-cut areas have been in each landscape. The amount/diversity of deadwood affected positively the α-diversity of all species, but its effect turned negative in clear cut stands. Exotic deadwood had an overall negative effect on α diversity of fungivores and was more marked as the cover of native forest increased within landscapes. The γ diversity of all species and predators responded negatively to CV(CC), while fungivores responded negatively to the current native forest cover. Deadwood and landscape-scale management had nonlinear effects on γ diversity, with the deadwood composition effect being dependent on clear-cut cover. All species and predators were less diverse as the proportion of exotic deadwood increased, but this effect turned positive within landscapes with high CV(CC). Landscape-scale forest management has long- and short-term effects on saproxylic beetles that are modulated by deadwood and propagate through species functional dimensions.