Remotely sensed landscape heterogeneity as a rapid tool for assessing local biodiversity value in a highly modified New Zealand landscape

The widespread conversion of natural habitats to agricultural land has created a need to integrate intensively managed landscapes into conservation management priorities. However, there are no clearly defined methods for assessing the conservation value of managed landscapes at the local scale. We used remotely sensed landscape heterogeneity as a rapid practical tool for the assessment of local biodiversity value within a predominantly agricultural landscape in Canterbury, New Zealand. Bird diversity was highly significantly correlated with landscape heterogeneity, distance from rivers and the Christchurch central business district, altitude and average annual household income, indicating that remotely sensed landscape heterogeneity is a good predictor of local biodiversity patterns. We discuss the advantages and limitations of using geographic information systems to determine local areas of high conservation value.     

Remote sensing variables as predictors of habitat suitability of the viscacha rat (<Emphasis Type="Italic">Octomys mimax</Emphasis>), a rock-dwelling mammal living in a desert environment

Identifying high-quality habitats across large areas is a central goal in biodiversity conservation. Remotely sensed data provide the opportunity to study different habitat characteristics (e.g., landscape topography, soil, vegetation cover, climatic factors) that are difficult to identify at high spatial and temporal resolution on the basis of field studies. Our goal was to evaluate the applicability of remotely sensed information as a potential tool for modeling habitat suitability of the viscacha rat (Octomys mimax), a rock-dwelling species that lives in a desert ecosystem. We fitted models considering raw indices (i.e., green indices, Brightness Index (BI) and temperature) and their derived texture measures on locations used by and available for the viscacha rat. The habitat preferences identified in our models are consistent with results of field studies of landscape use by the viscacha rat. Rocky habitats were well differentiated by the second-order contrast of BI, instead of BI only, making an important contribution to the global model by capturing the heterogeneity of the substratum. Furthermore, rocky habitats are able to maintain more vegetation than much of the surrounding desert; hence, their availability might be estimated using SATVI (Soil Adjusted Total Vegetation Index) and its derived texture measures: second-order contrast and entropy. This is the first study that evaluates the usefulness of remotely sensed data for predicting and mapping habitat suitability for a small-bodied rock dwelling species in a desert environment. Our results may contribute to conservation efforts focused on these habitat specialist species by using good predictors of habitat quality.     

Modelling avian biodiversity using raw,unclassified satellite imagery

Applications of remote sensing for biodiversity conservation typically rely on image classifications that do not capture variability within coarse land cover classes. Here, we compare two measures derived from unclassified remotely sensed data, a measure of habitat heterogeneity and a measure of habitat composition, for explaining bird species richness and the spatial distribution of 10 species in a semi-arid landscape of New Mexico. We surveyed bird abundance from 1996 to 1998 at 42 plots located in the McGregor Range of Fort Bliss Army Reserve. Normalized Difference Vegetation Index values of two May 1997 Landsat scenes were the basis for among-pixel habitat heterogeneity (image texture), and we used the raw imagery to decompose each pixel into different habitat components (spectral mixture analysis). We used model averaging to relate measures of avian biodiversity to measures of image texture and spectral mixture analysis fractions. Measures of habitat heterogeneity, particularly angular second moment and standard deviation, provide higher explanatory power for bird species richness and the abundance of most species than measures of habitat composition. Using image texture, alone or in combination with other classified imagery-based approaches, for monitoring statuses and trends in biological diversity can greatly improve conservation efforts and habitat management.     

不同干扰背景下景观指数与物种多样性的多尺度效应——以巩义市为例

以黄河中下游山地丘陵区的巩义市为研究区,采用典型样地法对灌草丛、人工林和农田边缘3种不同干扰背景下的自然、半自然生境内的植物进行调查。基于景观生态学原理,在地理信息系统技术支持下,借助于Fragstatta3.3软件,以调查样地为中心,计算了150、250、500、750、1000、1250、1500m不同半径缓冲区内表征景观形状(Edge and patch shape)、边缘对照(Edge contrast)、相似度和邻近度(Proximity and similarity)、景观多样性(Diversity)、基质(Texture)、斑块大小和密度(Patch size and patch density)共6类52个指数,运用冗余分析(RDA)筛选出不同尺度下对该区农业景观中植物多样性有显著影响的景观指数。结果表明:不同尺度,景观指数对物种多样性的影响变化显著。灌草丛生境,在500—750m范围内,SHAPE_AM指数和PARA_AM指数能够很好的解释物种多样性,解释量为33.6%;人工林生境,SHAPE_AM指数、AREA_CV指数、SIMI指数和PAFRAC指数在1000—1250m范围内对物种多样性的解释量达到48.1%;农田边缘生境,GYRATE_CV指数、ENN_CV指数、PARA_MN指数和FRAC_AM指数在750—1250m范围内对物种多样性影响显著,解释量为32%。其中,辛普森多样性指数(SIDI)与灌草丛物种多样性在750—1250m范围内作用显著,ENN_CV指数仅对农田边缘物种多样性影响较大。景观指数对物种多样性的影响具有尺度依赖性,未来应全面综合探讨这些指数的尺度效应及在景观生态学中的应用。     

Linking Land‐Use Scenarios,Remote Sensing and Monitoring to Project Impact of Management Decisions

Large‐scale modifications of natural ecosystems lead to mosaics of natural, semi‐natural and intensively used habitats. To improve communication in conservation planning, managers and other stakeholders need spatially explicit projections at the landscape scale of future biodiversity under different land‐use scenarios. For that purpose, we visualized the potential effect of five forest management scenarios on the avifauna of Kakamega Forest, western Kenya using different measures of bird diversity and GIS data. Future projections of bird diversity combined: (1) remotely sensed data on the spatial distribution of different forest management types; (2) field‐based data on the biodiversity of birds in the different management types; and (3) forest management scenarios that took into account possible views of various stakeholder groups. Management scenarios based on the species richness of forest specialists were very informative, because they reflected differences in the proportions of near‐natural forest types among the five scenarios. Projections based on community composition were even more meaningful, as they mirrored not only the proportions of near‐natural forest types, but also their perimeter to area ratios. This highlights that it is important to differentiate effects of the total area of available habitat and the degree of habitat fragmentation, both for species richness and community composition. Furthermore, our study shows that an approach that combines land‐use scenarios, remote sensing and field data on biodiversity can be used to visualize future biodiversity. As such, visualizations of alternative scenarios are valuable for successful communication about conservation planning considering different groups of stakeholders in species‐rich tropical forests.     

农业景观生物多样性与害虫生态控制

现代农业的一个重要特征就是人类对农田生态系统的干扰强度及频率不断增加,严重影响农业景观的结构及其生物多样性.农业景观结构的变化及其生物多样性的丧失,必然引起生态系统服务功能的弱化,不利于实施以保护自然天敌为主的害虫生态控制.农业的集约化经营导致自然生境破碎化,减少了农业景观的复杂性,使得作物和非作物变成一种相对离散化的生境类型和镶嵌的景观格局;破碎化的生境不仅会减少某些物种的丰度,还会影响物种之间的相互关系及生物群落的多样性和稳定性.非作物生境类型如林地、灌木篱墙、田块边缘区、休耕地和草地等,是一种比较稳定的异质化环境.非作物生境较少受到干扰,可以为寄生性和捕食性节肢动物提供适宜的越冬或避难场所以及替代猎物、花粉和花蜜等资源,因此,非作物生境有利于自然天敌的栖息和繁衍,也有利于它们迁入邻近的作物生境中对害虫起到调节和控制作用.景观的格局-过程-尺度影响农田生物群落物种丰富度、多度、多样性以及害虫与天敌之间的相互作用.从区域农业景观系统的角度出发,运用景观生态学的理论和方法来研究作物、害虫、天敌等组分在不同斑块之间的转移过程和变化规律,揭示害虫在较大尺度和具有异质性的空间范围内的灾变机理,可为利用农业景观生物多样性来保护农田自然天敌,实施害虫的区域性生态控制提供新的研究思路和手段.     

Linear woodlots increase wild bee abundance by providing additional food sources in an agricultural landscape

1. Mid-field woodlots play an important role in maintaining biodiversity in agricultural landscapes. However, it is not clear whether non-linear or linear woodlots are most beneficial for wild bee conservation.
2. We assessed the attractiveness of two common types of woodlots in an agricultural landscape in northern Poland (non-linear and linear: 7 and 9 sites, respectively) in terms of wild bee abundance, species richness, and functional diversity.
3. Linear habitats had higher abundance of wild bees. However, woodlot type did not affect wild bee species composition or functional trait composition. Species composition responded significantly to measures of syntaxonomic heterogeneity and landscape heterogeneity. Woodlot area, landscape context (isolation and landscape heterogeneity), and syntaxonomic heterogeneity explained most of the differences among habitats (non-linear vs. linear) in wild bee abundance and species richness, regardless of the habitat type. The higher attractiveness of linear woodlots was due to increased food availability in the herbaceous layer in the spring–summer (June) and summer (July–August) periods.
4. Linear woodlots have the potential to be used as tools for integrating agricultural production with biodiversity conservation and ecosystem services.

     

Altered beta diversity in post‐agricultural woodlands: two hypotheses and the role of scale

Agricultural land use commonly leaves a persistent signature on the ecosystems that develop after agricultural abandonment. This agricultural legacy limits the biodiversity supported by post‐agricultural habitats compared to remnant habitats that have never been used for agriculture. In particular, beta diversity (variation in community composition across space) at both large and small spatial scales can differ between post‐agricultural and remnant habitats, but we do not understand the mechanisms driving these differences. We surveyed plant communities at 29 pairs of post‐agricultural and remnant longleaf pine woodlands (58 total woodlands) to test for patterns consistent with two hypothesized mechanisms for why post‐agricultural ecosystems support altered beta diversity. 1) Post‐agricultural sites support different levels of underlying environmental heterogeneity than remnants. 2) Establishment of species associated with remnant habitats into post‐ agricultural woodlands is limited by dispersal and/or environmental conditions. We found no support for the environmental heterogeneity hypothesis and strong support for the idea that species establishment limits reassembling communities. Our results revealed a novel and important nuance to the establishment limitation hypothesis: spatially constrained, but not completely prevented, re‐establishment of remnant‐associated species in post‐agricultural woodlands increased within‐site beta diversity, contrary to results at larger among‐site (landscape) scales. Our use of a powerful paired‐site design permits these insights into how agriculture and abandonment affect beta diversity at two spatial scales, highlighting the prominent influence of edges even a half century after agricultural abandonment. The importance of constrained species establishment during ecosystem recovery, and its scale‐dependent effect, could provide valuable guidance to enhance the utility of post‐agricultural habitats for biodiversity conservation.     

The relationship between the spectral diversity of satellite imagery,habitat heterogeneity,and plant species richness

Assessment of habitat heterogeneity and plant species richness at the landscape scale is often based on intensive and extensive fieldwork at great cost of time and money. We evaluated the use of satellite imagery as a quantitative measure of the relationship between the spectral diversity of satellite imagery, habitat heterogeneity, and plant species richness. A 16 km² portion of a military training area in Germany was systematically sampled by plant taxonomic experts on a grid of one hundred 1-ha plots. The diversity of disturbance types, resulting habitat heterogeneity, and plant species richness were determined for each plot. Using an IKONOS multispectral satellite image, we examined 168 metrics of spectral diversity as potential indicators of those independent variables. Across all potential relationships, a simple count of values per spectral band per plot, after compressing the data from the original 11-bit format with 2048 potential values per band into a maximum of 100 values per band, resulted in the most consistent predictor for various metrics of habitat heterogeneity and plant species richness. The count of values in the green band generally out-performed the other bands. The relationship between spectral diversity and plant species richness was stronger than for measures of habitat heterogeneity. Based on the results, we conclude that remotely sensed assessment of spectral diversity, when coupled with limited ground-truthing, can provide reasonable estimates of habitat heterogeneity and plant species richness across broad areas.     

Heterogeneity from increasing crop types: effect on carabid beetles

We investigated the effect of crop type heterogeneity on carabid beetles in intensively managed agricultural landscapes. We compared different crops and habitat type configurations and compositions. In addition we assessed the effect of artificial fragmentation by paved roads and water channels in an agricultural landscape. Crop type heterogeneity negatively affected carabid assemblages. Spatial dissection by artificial structures had an even more negative effect on carabid diversity. The nested structure of the carabid assemblages among crop types was caused by a negative response to heterogeneity in the agricultural landscape. Even though crop types in an intensive agricultural landscape increased, the landscape may tend to fragment habitat. Although artificially fragmented habitats had more unstable carabid assemblages, heterogeneity from different crop types has also been shown to be a characteristic of fragmented landscapes. To produce a positive relationship between biodiversity and heterogeneity in an agricultural landscape, farming intensity should be reduced to allow for the conversion of highly productive lands into more natural habitats.     

Using prioritisation tools to strategically restore vegetation communities in fragmented agricultural landscapes

Restoring native habitats in heavily cleared and fragmented areas such as agricultural landscapes is important to maintain and increase remaining native floral and faunal communities. Identifying priority vegetation types for restoration – as well as the parcels of land where this restoration could take place at a landscape scale – may assist in strategically protecting these biodiversity assets. To prioritise the restoration of terrestrial habitats around an ecologically and culturally significant Ramsar‐listed wetland in South Australia, we used the spatial prioritisation tool Marxan. Originally designed for prioritising the protection of reserve areas, Marxan can also be used to identify parcels of land for restoration purposes. We tested how Marxan prioritised the restoration of four distinct vegetation types around the Coorong and Lower Lakes region of South Australia using the inverse of habitat remnancy as a cost and soil type and distance to ecologically significant bird species as a conservation feature. By prioritising restoration activities around certain landscape features, such as remnant areas, our results indicate that we would be able to strategically restore parcels of native habitat that would maximise biodiversity outcomes. This study highlights the need for robust input data, such as priority vegetation types and bird species associated with these habitats, to ensure informative modelling outputs. It also suggests that other measures, such as the cost of different land types, should be included in future restoration planning. Finally, we illustrate how prioritisation tools such as Marxan can be used by natural resource managers to restore areas within fragmented agricultural landscapes.     

Avifaunal responses to habitat fragmentation in the threatened littoral forests of south-eastern Madagascar

Aim Madagascar's lowland forests are both rich in endemic taxa and considered to be seriously threatened by deforestation and habitat fragmentation. However, very little is known about how these processes affect biodiversity on the island. Herein, we examine how forest bird communities and functional groups have been affected by fragmentation at both patch and landscape scales, by determining relationships between species richness and individual species abundance and patch and landscape mosaic metrics. Location Littoral forest remnants within south‐eastern Madagascar. Methods We sampled 30 littoral forest remnants in south‐eastern Madagascar, within a landscape mosaic dominated by Erica spp. heathland. We quantified bird community composition within remnants of differing size, shape and isolation, by conducting point counts in November–December in 2001 and October–November 2002. Each remnant was characterized by measures of remnant area, remnant shape, isolation, and surrounding landscape complexity. We used step‐wise regression to test the relationship between bird species richness and landscape structural elements, after correcting for sampling effort. Relationships between bird species abundances and the landscape variables were investigated with Canonical Correspondence Analysis and binomial logistic regression modelling. Results Bird species richness and forest‐dependent bird species richness were significantly (P < 0.01) explained by remnant area but not by any measure of isolation or landscape complexity. The majority of forest‐dependent species had significant relationships with remnant area. Minimum area requirements for area‐sensitive species ranged from 15 to 150 ha, with the majority of species having area requirements > 30 ha. Surprisingly, there was no relationship between bird body size and minimum area requirement. Forest‐dependent canopy insectivorous species and large canopy frugivorous species were the most sensitive functional groups, with > 90% species sensitivity within each group. The distribution of four forest‐dependent species also appeared to be related to remnant shape where remnant area was < 100 ha. Main conclusions The majority of forest‐dependent species, including many that are considered widespread and common, were found to have significant relationships with fragment size, indicating that they are sensitive to processes associated with habitat loss and fragmentation. As deforestation and habitat fragmentation remain serious problems on the island, it follows that many forest‐dependent bird species will decline in abundance and become locally extinct. At the regional scale, we urge that large (> 200 ha) blocks of littoral forest are awarded protected status to preserve their unique bird community.     

Landscape heterogeneity as an ecological filter of species traits

Landscape heterogeneity is a major driver of biodiversity in agricultural areas and represents an important parameter in conservation strategies. However, most landscape ecology studies measure gamma diversity of a single habitat type, despite the assessment of multiple habitats at a landscape scale being more appropriate. This study aimed to determine the effects of landscape composition and spatial configuration on life-history trait distribution in carabid beetle and herbaceous plant communities. Here, we assessed the gamma diversity of carabid beetles and plants by sampling three dominant habitats (woody habitats, grasslands and crops) across 20 landscapes in western France. RLQ and Fourth Corner three-table analyses were used to assess the association of dispersal, phenology, reproduction and trophic level traits with landscape characteristics. Landscape composition and configuration were both significant in explaining functional composition. Carabid beetles and plants showed similar response regarding phenology, i.e. open landscapes were associated with earlier breeding species. Carabid beetle dispersal traits exhibited the strongest relationship with landscape structure; for instance, large and apterous species preferentially inhabited woody landscapes, whereas small and macropterous species preferentially inhabited open landscapes. Heavy seeded plant species dominated in intensified agricultural landscapes (high % crops), possibly due to the removal of weeds (which are usually lightweight seeded species). The results of this study emphasise the roles of landscape composition and configuration as ecological filters and the importance of preserving a range of landscape types to maintain functional biodiversity at regional scales.     

Seeking parsimony in landscape metrics

Numerous metrics describing landscape patterns have been used to explain landscape-scale habitat selection by birds. The myriad metrics, their complexity, and inconsistent responses to them by birds have led to a lack of clear recommendations for managing land for desired species. The amount of a target land cover type in the landscape (percentage cover) often has been a useful indicator of the likelihood of species occurrence or of habitat selection; is it also a more adequate and parsimonious measure for explaining species distributions than patch size or more complex measures of landscape configuration? We examined responses of 6 woodland-interior bird species to the percentage tree cover within prescribed areas and to patch size, edge density, and other metrics. We examined responses in 2 landscapes: a mixed woodland-savanna and an eastern deciduous forest. For these 6 species, percentage tree cover explained bird occurrence as well as or better than other measures in both study areas. We then repeated the analysis on a larger group of woodland species, including those associated with woodland edges. The bird species we studied had varied responses to landscape metrics, but percentage tree cover was the strongest explanatory variable overall. Although percentage cover estimated from remotely sensed data is an inexact representation of habitat in the landscape, it does appear to be reliable and easy to conceptualize, relative to other measures. We suggest that, at least for woodland habitat, percentage cover is a broadly useful measure that can be helpful in pragmatic questions of explaining responses to landscapes or in anticipating responses to landscape change. © 2011 The Wildlife Society.     

Remotely sensed spectral heterogeneity as a proxy of species diversity: Recent advances and open challenges

Environmental heterogeneity is considered to be one of the main factors associated with biodiversity given that areas with highly heterogeneous environments can host more species due to their higher number of available niches. In this view, spatial variability extracted from remotely sensed images has been used as a proxy of species diversity, as these data provide an inexpensive means of deriving environmental information for large areas in a consistent and regular manner. The aim of this review is to provide an overview of the state of the art in the use of spectral heterogeneity for estimating species diversity. We will examine a number of issues related to this theme, dealing with: i) the main sensors used for biodiversity monitoring, ii) scale matching problems between remotely sensed and field diversity data, iii) spectral heterogeneity measurement techniques, iv) types of species taxonomic diversity measures and how they influence the relationship between spectral and species diversity, v) spectral versus genetic diversity, and vi) modeling procedures for relating spectral and species diversity. Our review suggests that remotely sensed spectral heterogeneity information provides a crucial baseline for rapid estimation or prediction of biodiversity attributes and hotspots in space and time.     

农业景观中非农景观要素结构特征对植物物种多样性的影响——以封丘县为例

农业景观中的非农生境对维持与提高农业景观的生物多样性具有非常关键的作用。为了探究非农生境的相关结构属性对农业景观中植物物种多样性的影响,选择黄河下游平原区的封丘县为研究区域,对研究区内42个样点的非农生境进行植物多样性调查,并对各个样点周围1 km范围内的非农景观要素进行了提取,分析不同非农生境中植物物种组成及其景观要素的构成、结构及空间配置对植物物种多样性的影响。研究结果表明:不同类型的非农生境中,物种组成共有种相对较多,特有种或指示种较少;林地与树篱具有相对较高的物种多样性,以沟渠为生境的植物物种组成与其它两种生境类型相比存在明显差异;林地与树篱/沟渠的组成比例相当时,植物物种丰富度最高;景观指数对不同非农生境中的植物物种具有明显影响,景观破碎化及人为干扰指数的影响较为显著。未来在对本区域内农业景观进行结构优化的过程中,应从非农景观要素的改造入手。通过调整和设置非农景观要素的不同类型及比例、合理改造其结构与空间配置,为最终实现农业景观的有效管理与可持续健康发展奠定重要的研究基础。     

Agricultural intensification alters bat assemblage composition and abundance in a dynamic Neotropical landscape

The recent trend of agricultural intensification in tropical landscapes poses a new threat to biodiversity conservation. Conversion of previously heterogeneous agricultural landscapes to intensive plantation agriculture simplifies and homogenizes the landscape, reducing availability, and connectivity of natural habitat for native species. To assess the impact of agricultural intensification on bats, we characterized the bat assemblage in the Sarapiquí region of Costa Rica, where heterogeneous land uses are being converted to intensive, large‐scale pineapple plantations. In 2012 and 2013, we sampled bats in 20 remnant forest patches surrounded by varying proportions of pasture, mature forest, and pineapple and captured 1821 individual bats representing 39 species. We used ordination analyses to evaluate changes in species composition, where pineapple is the main component of the agricultural matrix. We identified landscape metrics specifically correlated with pineapple and used multiple linear regression to test their effects on bat species richness, diversity, and guild‐specific relative abundance. Results suggest pineapple expansion is driving changes in assemblage composition in remnant forest patches, resulting in new assemblages with higher proportions of frugivorous bats and lower proportions of insectivorous bats than in continuous mature forests. In addition, while pineapple does not diminish total bat species richness and diversity, the reduced forest cover and increased distance between forest patches in pineapple plantations has a significant negative impact on the relative abundance of insectivores. We also identify a potential threshold effect whereby patches surrounded by more than 50 percent forest can retain assemblage composition similar to that found in continuous mature forest.     

Influence of crop type,heterogeneity and woody structure on avian biodiversity in agricultural landscapes

Agriculture is a primary factor underlying world-wide declines in biodiversity. However, different agricultural systems vary in their effects depending on their resemblance to the natural ecosystem, coverage across the landscape, and operational intensity. We combined data from the North American Breeding Bird Survey with remotely sensed measures of crop type and linear woody feature (LWF) density to study how agricultural type, woody structure and crop heterogeneity influenced the avian community at landscape scales across a broad agricultural region of eastern Canada. Specifically, we examined whether 1) avian diversity and abundance differed between arable crop agriculture (e.g., corn, soy) and forage (e.g., hay) and pastoral agriculture, 2) whether increasing the density of LWF enhances avian diversity and abundance, and 3) whether increasing the heterogeneity of arable crop types can reduce negative effects of arable crop amount. Avian diversity was lower in landscapes dominated by arable crop compared to forage agriculture likely due to a stronger negative correlation between arable cropping and the amount of natural land cover. In contrast, total avian abundance did not decline with either agricultural type, suggesting that species tolerant to agriculture are compensating numerically for the loss of non-tolerant species. This indicates that bird diversity may be a more sensitive response than bird abundance to crop cover type in agricultural landscapes. Higher LWF densities had positive effects on the diversity of forest and shrub bird communities as predicted. Higher crop heterogeneity did not reduce the negative effects of high crop amount as expected except for wetland bird abundance. In contrast, greater crop heterogeneity actually strengthened the negative effects of high crop amount on forest bird abundance, shrub-forest edge bird diversity and total bird diversity. We speculate that this was due to negative correlations between crop heterogeneity and the amount of shrub and forest habitat patches in crop-dominated landscapes in our study region. The variable response to crop heterogeneity across guilds suggests that policies aimed at crop diversification may not enhance avian diversity on their own and that management efforts aimed at the retention of natural forest and shrub patches, riparian corridors, and hedge-rows would be more directly beneficial.     

Arthropod colonisation of natural and experimental logs in an agricultural landscape: Effects of habitat,isolation, season and exposure time

Summary Habitat restoration is commonly conducted in agricultural landscapes with the aim of restoring biodiversity. Some species, however, might not be able to migrate to restored habitats, and vital habitat elements, such as logs, may be missing. We compared arthropod assemblages under logs amongst different land‐use types: pastures, revegetation and woodland remnants, in south‐eastern Australia. We also supplemented habitats with logs, placed out in different seasons and for different periods of time to determine how season and exposure time affect arthropod composition. We compared assemblages under logs in revegetation adjacent to and isolated from woodland remnants to test the role of habitat connectivity. Arthropod assemblages differed significantly between land‐use types, with pastures most different to remnants. These differences corresponded with differences in log microhabitat. Time was an important determinant of community composition, but habitat (remnant vs revegetated) and revegetation connectivity (adjacent vs isolated patch) were not. Time affected assemblage composition in two distinct ways: first, time of year (November vs January), and second, exposure time of logs (1 vs 3 months) affected composition. Exposure time effects may indicate dispersal limitation, but the proportion of wingless species did not depend on exposure time or connectivity. We conclude that the log fauna in this landscape responds to microenvironments and seasonal change but is not strongly dispersal limited, allowing it to respond rapidly to habitat restoration. The pre‐agricultural landscape likely shared many features with the modified landscape, such that many species possess traits and behaviours that allow them to move through and persist in the matrix.