Carnivore-livestock conflicts: determinants of wolf (Canis lupus) depredation on sheep farms in Finland

Wolves (Canis lupus) have recently expanded their distribution range into western and southern Finland, which has not hosted breeding wolves for over 100 years. This has raised concerns and public debate over wolf-livestock conflicts. Between 1998 and 2004 there were 45 wolf attacks on sheep on 34 farms. To assess the risk wolves may pose to sheep husbandry, we used data on depredation, sheep management, landscape structure and moose and wolf populations from continental Finland outside the area of reindeer husbandry to build models of the factors that may predispose sheep farms to wolf depredation. Our results provided evidence that sheep farms with the highest risk of wolf depredation were those located in regions where wolves were abundant. These farms were usually located close to the Russian border where the landscape is a mosaic of forest, wetlands and clear cut areas. These regions are sparsely populated by humans and farms are located far from each other. Finally, we generated probability maps based on generalised additive modelling to predict the risk of wolf predation on livestock in farms of southern Finland.     

Spatial risk modeling of cattle depredation by black vultures in the midwestern United States

Negative economic impacts resulting from wildlife disrupting livestock operations through depredation of stock are a cause of human-wildlife conflict. Management of such conflict requires identifying environmental and non-environmental factors specific to a wildlife species' biology and ecology that influence the potential for livestock depredation to occur. Identification of such factors can improve understanding of the conditions placing livestock at risk. Black vultures (Coragyps atratus) have expanded their historical range northward into the midwestern United States. Concomitantly, an increase in concern among agricultural producers regarding potential black vulture attacks on livestock has occurred. We estimated area with greater or lesser potential for depredation of domestic cattle by black vultures across a 6-state region in the midwestern United States using an ensemble of small models (ESM). Specifically, we identified landscape-scale spatial factors, at a zip code resolution, associated with reported black vulture depredation on cattle in midwestern landscapes to predict future potential livestock depredation. We hypothesized that livestock depredation would be greatest in areas with intensive beef cattle production close to preferred black vulture habitat (e.g., areas with fewer old fields and early successional vegetation paired with more direct edge between older forest and agricultural lands). We predicted that the density of cattle within the county, habitat structure, and proximity to anthropogenic landscape features would be the strongest predictors of black vulture livestock-depredation risk. Our ESM estimated the relative risk of black vulture-cattle depredation to be between 0.154–0.631 across our entire study area. Consistent with our hypothesis, areas of greatest predicted risk of depredation correspond with locations that are favorable to vulture life-history requirements and increased potential to encounter livestock. Our results allow wildlife managers the ability to predict where black vulture depredation of cattle is more likely to occur in the future. It is in these areas where extension and outreach efforts aimed at mitigating this conflict should be focused. Researchers and wildlife managers interested in developing or employing tools aimed at mitigating livestock-vulture conflicts can also leverage our results to select areas where depredation is most likely to occur.     

黑土侵蚀区生态重建的景观结构与功能分析

以黑龙江省拜泉县为案例,研究了区域生态恢复与生态重建对景观结构及其水土保持功能的调控.在GIS支持下,结合野外调查数据,对县域水平的生态建设成果进行了空间表达和定量辨识.对比分析1989年和2002年类型水平景观指数及13年来景观类型的转移面积和转移方向、林网宏观结构变化、水库塘坝空间分布与数量变化;土地利用和景观结构调整对水蚀、风蚀的控制以及水库塘坝的蓄水功能变化.结果表明,大规模生态建设下,区域景观类型数量和空间配置的变化对发挥其水土保持功能起到很好的调控作用.1989～2002年,耕地面积减少24731.01hm²,林草地和水体面积增加了13 567.53 hm²和1 190.9 hm².全县55%的水土流失面积得到治理,82.2%的农田得到林网防护,43.7%的景观地表超渗径流得到集蓄.景观结构调整应注意增加林草地等类型斑块的聚集度;调节林网连接度、环度及网眼大小;增加水库塘坝的泄洪与灌溉配套设施等.     

Spatial heterogeneity in landscape structure influences dispersal and genetic structure: empirical evidence from a grasshopper in an agricultural landscape

Dispersal may be strongly influenced by landscape and habitat characteristics that could either enhance or restrict movements of organisms. Therefore, spatial heterogeneity in landscape structure could influence gene flow and the spatial structure of populations. In the past decades, agricultural intensification has led to the reduction in grassland surfaces, their fragmentation and intensification. As these changes are not homogeneously distributed in landscapes, they have resulted in spatial heterogeneity with generally less intensified hedged farmland areas remaining alongside streams and rivers. In this study, we assessed spatial pattern of abundance and population genetic structure of a flightless grasshopper species, Pezotettix giornae, based on the surveys of 363 grasslands in a 430‐km² agricultural landscape of western France. Data were analysed using geostatistics and landscape genetics based on microsatellites markers and computer simulations. Results suggested that small‐scale intense dispersal allows this species to survive in intensive agricultural landscapes. A complex spatial genetic structure related to landscape and habitat characteristics was also detected. Two P. giornae genetic clusters bisected by a linear hedged farmland were inferred from clustering analyses. This linear hedged farmland was characterized by high hedgerow and grassland density as well as higher grassland temporal stability that were suspected to slow down dispersal. Computer simulations demonstrated that a linear‐shaped landscape feature limiting dispersal could be detected as a barrier to gene flow and generate the observed genetic pattern. This study illustrates the relevance of using computer simulations to test hypotheses in landscape genetics studies.     

Adjacent woodlands rather than habitat connectivity influence grassland plant,carabid and bird assemblages in farmland landscapes

One response to biodiversity decline is the definition of ecological networks that extend beyond protected areas and promote connectivity in human-dominated landscapes. In farmland, landscape ecological research has focused more on wooded than open habitat networks. In our study, we assessed the influence of permanent grassland connectivity, described by grassland amount and spatial configuration, on grassland biodiversity. We selected permanent grasslands in livestock farming areas of north-western France, which were sampled for plants, carabids and birds. At two spatial scales we tested the effects of amount and configuration of grasslands, wooded habitats and crops on richness and abundance of total assemblages and species ecological groups. Grassland connectivity had no significant effects on total richness or abundance of any taxonomic group, regardless of habitat affinity or dispersal ability. The amount of wooded habitat and length of wooded edges at the 200 m scale positively influenced forest and generalist animal groups as well as grassland plant species, in particular animal-dispersed species. However, for animal groups such as open habitat carabids or farmland bird specialists, the same wooded habitats negatively influenced richness and abundance at the 500 m scale. The scale and direction of biodiversity responses to landscape context were therefore similar among taxonomic groups, but opposite for habitat affinity groups. We conclude that while grassland connectivity is unlikely to contribute positively to biodiversity, increasing or maintaining wooded elements near grasslands would be a worthwhile conservation goal. However, the requirements of open farmland animal species groups must be considered, for which such action may be deleterious.     

黄土丘陵沟壑区景观格局演变特征——以陕西省延安市为例

以陕西省延安市1985年、2000年和2008年三期1∶25万景观单元类型图,1∶5万地形图等生成的数字高程模型(DEM)为数据源,基于ArcGIS 9.3软件,采用多距离空间聚类、景观单元类型转移矩阵、空间数据叠加分析等方法分析了延安市景观格局的演变特征。结果表明:延安市的景观是由林地、灌木、草地和农田等基本景观单元构成的复合景观;研究期间农地面积急剧减少,流失的农地主要转变为林地、草地、灌木和聚落,除农地和裸地外,其他景观单元类型面积均有不同程度的增加;1985—2008年,林地、灌木和草地聚集的最大尺度减小,而农田聚集的最大尺度变大,农田和草地的空间聚集强度明显小于林地和灌木;延安市主要景观单元类型演变主要发生在海拔1100—1500 m之间的区域和坡度范围7—21°之间的区域,但农田向聚落的演变主要发生在海拔较低(900—1300 m)、坡度较缓(7°)的平川缓丘地带。1999年之前,经济的迅速发展是延安市景观格局演变的主要驱动因素;而1999年之后,国家推行的退耕还林(还草)等一系列生态重建措施成为延安市景观格局变化的主要驱动因素。     

区域农田景观格局对麦蚜种群数量的影响

明确农田景观格局对麦田蚜虫种群的影响,是开展区域性害虫生态调控的重要理论依据之一。以区域性小麦种植区为研究对象,基于遥感影像与土地覆盖分类数据以及田间调查的蚜虫种群数据,计算景观格局指数,使用负二项分布的广义线性模型从农田景观、非作物生境景观和区域景观3个方面分析了区域农田景观格局对麦田蚜虫种群的影响。结果表明,蚜虫种群的数量与草地的平均斑块面积和最大斑块指数显著正相关,与县域的平均几何最邻近距离和面积加权平均斑块面积显著负相关,与耕地的面积加权平均斑块面积显著负相关,与耕地的斑块密度显著正相关。草地斑块面积的增大、区域景观与耕地的破碎化、区域景观的聚集会促进蚜虫种群数量的增加。使用草地的斑块面积和最大斑块指数、区域景观的平均几何最邻近距离可以预测蚜虫种群的发生量。非作物生境草地的斑块面积、耕地的破碎化、区域景观的空间分布及破碎化是影响麦田蚜虫种群发生的重要景观因素。     

The effect of land type diversity and spatial heterogeneity on farmland birds in Norway

The decline in farmland birds observed throughout Europe during recent decades has attracted much attention. Agricultural intensification or land abandonment are commonly forwarded as key drivers. Several countries have established agri-environmental schemes (AES) to counter these negative trends among farmland birds. This paper reports a study of the relationship between land use and bird species in the agricultural landscape of Norway. The main objective was to investigate the effect of spatial heterogeneity and diversity of land use on total richness and abundance of farmland birds at a national level.Monitoring the distribution and abundance of birds is part of the Norwegian monitoring programme for agricultural landscapes. The monitoring programme is based on mapping of 1 × 1 km squares distributed across the entire agricultural landscape. Within these squares permanent observation points are established for bird monitoring. Detailed interpretation of aerial photographs provides the land classification. We tested the relationship between landscape metrics at different levels of land type detail and species richness and abundance of farmland and non-farmland birds.There was a positive relationship between species richness and abundance of farmland birds and agricultural area. For non-farmland birds the relationship was negative. Spatial heterogeneity of land use was a significant positive factor for both farmland and non-farmland species. High land type diversity was positive for farmland bird richness, but negative for abundance. Non-farmland bird richness was not affected by land type diversity, but abundance had a negative response.The results presented in this paper highlight the importance of a spatial heterogeneous landscape. However, we also found that land type diversity could negatively affect the abundance of both farmland and non-farmland birds. Our findings suggest a need for different management approaches depending on whether the aim is increased species richness or abundance. Achieving both aims with the same means might be difficult. We thus suggest a need for land use analyses before proper management strategies can be implemented.     

黄土区农业景观空间格局分析

景观空间格局分析是景观生态学研究的核心问题之一。本文用地理信息系统,分维分析和统计分析相结合,以１∶１万土地利用现状图为基础,选取斑块大小、分维数、斑块伸长指数、多样性、优势度、相对丰富度、破碎度等指标,陕北米脂县泉家沟流域农业景观的空间格局。结果显示,乔木林地、坡耕地、果园、草地和梯田农地的分维数较低,坝地、水库、灌溉农田、居信用地和灌木林地的人维数较高,斑块形状较为复杂。随着斑块面积的增加,农     

泾河流域分县景观格局特征及相关性

景观生态主要是研究生态系统的空间格局。因而很有必要对空间格局进行数量化的分析,在此基础上进行科学管理。应用斑块数、斑块面积、斑块密度、优势度、聚集度和分维数计算了泾河流域31个县景观格局的特征,首次以景观特征值为基础,将研究区域各县景观进行分类,并对不同类型的景观特征及相关性进行分析。结果表明,近年来流域破碎化程度有所增加,各景观指数值在研究区域之间变异很大。优势度和聚集度比较高的区域土地利用较单一,常常是以农用地为主导如咸阳、泾阳和乾县,或以农地和草地共同主导如环县。而优势度和聚集度较低的区域,土地利用较多样化,农地、林地和草地面积比例相近,如泾源、平凉、陇县、宁县和旬邑,这些县位于黄土丘陵沟壑区和黄土高塬沟壑区。高优势度、高聚集度和低分维数的区域为陕西省咸阳市,为泾河流域冲积平原区,土地利用以大面积的农用地为主导。景观指数的相关分析表明,3种主要的土地利用面积比例之间存在极显著负相关,林地面积和优势度、聚集度有极显著负相关,而草地面积和分维数存在极显著正相关,分维数高的县位于泾河流域中游的黄土高原沟壑区,分维数低的县位于下游河谷阶地和关中平原和黄土高原交界处。这种相关性表明了自然地貌及人类活动对景观的影响和干扰作用。     

Low-Intensity Agricultural Landscapes in Transylvania Support High Butterfly Diversity: Implications for Conservation

European farmland biodiversity is declining due to land use changes towards agricultural intensification or abandonment. Some Eastern European farming systems have sustained traditional forms of use, resulting in high levels of biodiversity. However, global markets and international policies now imply rapid and major changes to these systems. To effectively protect farmland biodiversity, understanding landscape features which underpin species diversity is crucial. Focusing on butterflies, we addressed this question for a cultural-historic landscape in Southern Transylvania, Romania. Following a natural experiment, we randomly selected 120 survey sites in farmland, 60 each in grassland and arable land. We surveyed butterfly species richness and abundance by walking transects with four repeats in summer 2012. We analysed species composition using Detrended Correspondence Analysis. We modelled species richness, richness of functional groups, and abundance of selected species in response to topography, woody vegetation cover and heterogeneity at three spatial scales, using generalised linear mixed effects models. Species composition widely overlapped in grassland and arable land. Composition changed along gradients of heterogeneity at local and context scales, and of woody vegetation cover at context and landscape scales. The effect of local heterogeneity on species richness was positive in arable land, but negative in grassland. Plant species richness, and structural and topographic conditions at multiple scales explained species richness, richness of functional groups and species abundances. Our study revealed high conservation value of both grassland and arable land in low-intensity Eastern European farmland. Besides grassland, also heterogeneous arable land provides important habitat for butterflies. While butterfly diversity in arable land benefits from heterogeneity by small-scale structures, grasslands should be protected from fragmentation to provide sufficiently large areas for butterflies. These findings have important implications for EU agricultural and conservation policy. Most importantly, conservation management needs to consider entire landscapes, and implement appropriate measures at multiple spatial scales.     

基于多源遥感数据的景观格局及预测研究

以TM、中巴资源卫星和环境与灾害监测预报小卫星等遥感影像为数据源,利用ENVI 4.7、ARCGIS 9.2、IDRISI 15等软件,研究了西安市辖区的景观特征与空间格局,预测了未来的景观变化,提出了景观格局预测的数据转化和多距离空间分析的精简步骤.结果表明:研究区的景观本底是一个由林地和耕地构成的复合景观基质,建设用地在研究时段内呈现持续增加趋势,且2004-2011年间的增加量高于2000-2004年间的增加量;林地面积略有降低,林地和草地总面积略呈增长趋势,水域和未利用地面积变化较小.研究时段内的景观破碎化程度在降低,林地景观的连通性增强了,耕地的降低了.各景观类型在所设定的最大预期研究尺度下均呈现显著的聚集空间格局;各年和各景观类型之间的聚集、随机和离散的临界阈值差别相对比较大;水域和未利用地的空间聚集强度明显高于耕地、林地、草地和城乡建设用地;耕地和草地空间分布存在一个异质性最大的特征尺度,且均出现了聚集分布、随机分布和离散分布3种分布格局,以2011年最为明显.利用景观指数法和多距离空间聚类分析方法研究景观格局特征的效果要比单一的景观指数法较理想.CA-Markov模型模拟的结果基本能够反映未来的景观格局状况.     

Forest structure and biomass in post-agricultural forests: Lessons learned with new spatial tools

Questions: With calls for afforestation to sequester carbon due to climate change, agricultural land will be converted to forests in the near future. Little is known about how the ecosystem services of reforested landscapes with an agricultural land-use history will differ from reference forests. Our objectives were to (i) test the hypothesis that forests with a history of agricultural land use can provide the same carbon storage and biomass ecosystem services as adjacent reference forests, given some recovery time; (ii) explore whether there is a lag in the recovery of forest community composition due to prior agricultural land use; and (iii) demonstrate how remote-sensing methods can improve our understanding of land-use legacies at large spatial scales. Location: Finger Lakes National Forest, NY, USA. Methods: Using historic air photos, landscape-scale lidar, and field surveys, we compared differences in biomass storage, forest structure, and vegetation communities between reference forests and post-agricultural forests at different stages of regeneration in the Finger Lakes National Forest, New York, USA. We also used lidar to create a spatial model of biomass across the landscape to analyze the spatial distribution of biomass across our study area. Results: We found biomass and forest structure in post-agricultural forests generally recovered to levels typical of reference forests within 50 years of abandonment. Conversely, we found the composition of woody and herbaceous communities still varied between reference and post-agricultural forests after 50 years of abandonment. Conclusions: Collectively our results indicate afforestation efforts can be effective for carbon sequestration at early stages of forest succession. Our spatial model of biomass indicated that biomass levels can be low in forests with extensive edge. Further research is needed to understand how contemporary landscape structure interacts with legacy effects of agriculture to affect biomass and other ecosystem services.     

Landscape‐scale accessibility of livestock to tigers: implications of spatial grain for modeling predation risk to mitigate human–carnivore conflict

Innovative conservation tools are greatly needed to reduce livelihood losses and wildlife declines resulting from human–carnivore conflict. Spatial risk modeling is an emerging method for assessing the spatial patterns of predator–prey interactions, with applications for mitigating carnivore attacks on livestock. Large carnivores that ambush prey attack and kill over small areas, requiring models at fine spatial grains to predict livestock depredation hot spots. To detect the best resolution for predicting where carnivores access livestock, we examined the spatial attributes associated with livestock killed by tigers in Kanha Tiger Reserve, India, using risk models generated at 20, 100, and 200‐m spatial grains. We analyzed land‐use, human presence, and vegetation structure variables at 138 kill sites and 439 random sites to identify key landscape attributes where livestock were vulnerable to tigers. Land‐use and human presence variables contributed strongly to predation risk models, with most variables showing high relative importance (≥0.85) at all spatial grains. The risk of a tiger killing livestock increased near dense forests and near the boundary of the park core zone where human presence is restricted. Risk was nonlinearly related to human infrastructure and open vegetation, with the greatest risk occurring 1.2 km from roads, 1.1 km from villages, and 8.0 km from scrubland. Kill sites were characterized by denser, patchier, and more complex vegetation with lower visibility than random sites. Risk maps revealed high‐risk hot spots inside of the core zone boundary and in several patches in the human‐dominated buffer zone. Validation against known kills revealed predictive accuracy for only the 20 m model, the resolution best representing the kill stage of hunting for large carnivores that ambush prey, like the tiger. Results demonstrate that risk models developed at fine spatial grains can offer accurate guidance on landscape attributes livestock should avoid to minimize human–carnivore conflict.     

Quantitative landscape dynamics in Denmark through the last three millennia based on the Landscape Reconstruction Algorithm approach

This paper explores the spatial and temporal land-cover variability within the main cultural landscape units in Denmark during the last 3,000 years. Quantitative estimates of the cover of trees, grasses, Cerealia and Calluna around nine Danish lakes were obtained using the recently developed Landscape Reconstruction Algorithm (LRA) (Sugita 2007a, b). The performance of the approach was evaluated by comparing reconstructed vegetation based on a.d. 1800 pollen spectra to land cover from historical maps of the same period. Although the model tended to overestimate grassland cover by 10–20%, the reconstructed vegetation was much more similar to the observed than the uncorrected pollen proportions. The LRA was then applied to 3,000 year long pollen records to reconstruct the vegetation development around each of the nine sites. The results support earlier conclusions regarding the relative stability of woodland, agrarian and heathland dominated landscapes in Denmark (Odgaard and Rasmussen 2000), with the distribution of the main landscape types determined by topography and soil characteristics. The present study indicates that the transition zones between agricultural and forest dominated landscapes were the most dynamic, acting as buffer zones where most of the expansions and contractions of agricultural activities took place. The quantitative vegetation reconstructions underline the importance of farming and especially pastoral activities in shaping the Danish landscapes throughout the study period.     

Predation on artificial ground nests in relation to forest fragmentation, agricultural land and habitat structure

The impacts of forest fragmentation agricultural land and habitat structure on depredation of artificial ground nests were studied in the cultivated area in central Finland and in the forest dominated area in Finnish Lapland The overall predation rate did not differ between the regions The overall predation rate was also independent of landscape characteristics forest patch size and the distance to patch edge However, nest predation was clearly affected by the agricultural land since the robbing rate in forest edges was higher near farmlands than further away This effect was caused by avian predators which proportional importance in predation was higher in the agricultural landscape than in the forest landscape In both regions, depredation correlated positively with high numbers of pine and spruce This can be mainly explained by the preference of predators over coniferous forest habitat as a living or hunting area     

基于3DLP指数的景观格局演变及预测分析

采用1987、1999、2009和2017年四期Landsat TM/OLI数据,结合GIS和RS技术,从类型和景观层面计算安化县四个年度的3DLP指数,分析安化县近30年来景观格局的动态演变并利用CA-Markov模型对2025年景观格局演变进行模拟和预测,为推动该县今后生态环境的进一步恢复和改善提供指导。结果表明:(1)林地是安化县的优势景观,对安化县景观的主控作用强。(2)从不同景观类型来看,1987—2017年期间安化县各景观破碎化情况均有所缓解,其中建设用地、林地面积增加,草地、水域、农地面积减少;林地、水域边界形状趋于简单化,建设用地、草地边界形状趋向复杂化,农地边界形状受人类活动影响较小。(3)从整体景观来看,安化县景观格局的演变主要是受到人为因素的影响,1999年整体边界形状变得更为规则,同时破碎化程度、景观异构性以及多样性有所提高。1999—2017年各类景观类型的面积比例差异增大,破碎化程度以及景观异质程度降低,优势景观类型份额增加。(4)根据预测结果来看,安化县整体趋向均衡化发展,边界形状趋向规则化,景观异质性程度降低,各类景观类型的面积比例差异减小,林地出现被其他景观蚕食分割的趋势,因此需要进一步提高对林地的重视和保护,限制其他景观类型对林地的干扰。     

How does forest landscape structure explain tree species richness in a Mediterranean context?

Although the strong relationship between vegetation and climatic factors is widely accepted, other landscape composition and configuration characteristics could be significantly related with vegetation diversity patterns at different scales. Variation partitioning was conducted in order to analyse to what degree forest landscape structure, compared to other spatial and environmental factors, explained forest tree species richness in 278 UTM 10 × 10 km cells in the Mediterranean region of Catalonia (NE Spain). Tree species richness variation was decomposed through linear regression into three groups of explanatory variables: forest landscape (composition and configuration), environmental (topography and climate) and spatial variables. Additionally, the forest landscape characteristics which significantly contributed to explain richness variation were identified through a multiple regression model. About 60% of tree species richness variation was explained by the whole set of variables, while their joint effects explained nearly 28%. Forest landscape variables were those with a greater pure explanatory power for tree species richness (about 15% of total variation), much larger than the pure effect of environmental or spatial variables (about 2% each). Forest canopy cover, forest area and land cover diversity were the most significant composition variables in the regression model. Landscape configuration metrics had a minor effect on forest tree species richness, with the exception of some shape complexity indices, as indicators of land use intensity and edge effects. Our results highlight the importance of considering the forest landscape structure in order to understand the distribution of vegetation diversity in strongly human-modified regions like the Mediterranean.     

Landscape attributes shape dung beetle diversity at multiple spatial scales in agricultural drylands

Land-use change is one of the main drivers of biodiversity loss worldwide, but its negative effects can vary depending on the spatial scale analyzed. Considering the continuous expansion of agricultural demand for land, it is urgent to identify the drivers that shape biological communities in order to balance agricultural production and biodiversity conservation in human-modified landscapes. We used a patch-landscape design and a multimodel inference approach to assess the effects of landscape composition and configuration at two spatial scales (patch and landscape) on the structure of dung beetle assemblages. We performed our study in the Caatinga, the largest dry forest in South America. We sampled 3,526 dung beetles belonging to 19 species and 11 genera. At patch scale, our findings highlight the positive relationship of forest cover and landscape heterogeneity with dung beetle diversity, which are the major drivers of beetle assemblages. Edge density, in turn, is a major driver at the landscape scale and has a negative effect on beetle diversity. Our results support the hypothesis that landscapes combining natural vegetation remnants and heterogeneous agricultural landscapes are the most effective at conserving the biodiversity of dung beetles in the Caatinga landscapes. Directing efforts to better understand the dynamics of dung beetles in agricultural lands can be helpful for policymakers and scientists to design agri-environment schemes and apply conservation strategies in tropical dry forests.     

Understanding Patchy Landscape Dynamics: Towards a Landscape Language

Patchy landscapes driven by human decisions and/or natural forces are still a challenge to be understood and modelled. No attempt has been made up to now to describe them by a coherent framework and to formalize landscape changing rules. Overcoming this lacuna was our first objective here, and this was largely based on the notion of Rewriting Systems, also called Formal Grammars. We used complicated scenarios of agricultural dynamics to model landscapes and to write their corresponding driving rule equations. Our second objective was to illustrate the relevance of this landscape language concept for landscape modelling through various grassland managements, with the final aim to assess their respective impacts on biological conservation. For this purpose, we made the assumptions that a higher grassland appearance frequency and higher land cover connectivity are favourable to species conservation. Ecological results revealed that dairy and beef livestock production systems are more favourable to wild species than is hog farming, although in different ways. Methodological results allowed us to efficiently model and formalize these landscape dynamics. This study demonstrates the applicability of the Rewriting System framework to the modelling of agricultural landscapes and, hopefully, to other patchy landscapes. The newly defined grammar is able to explain changes that are neither necessarily local nor Markovian, and opens a way to analytical modelling of landscape dynamics.