Landscapes in Time and Space

Landscape ecology has a temporal dimension, and the role of past processes in shaping landscapes is increasingly recognised. To date, the interface between landscape ecology and palaeoecology has proved most productive in understanding the impacts of climate change and in discovering the extent of past human impacts on ecosystems. Further areas of synergy are emerging. This Perspective gives selected examples of five main areas of synergy between palaeoecology and landscape ecology: dynamic landscape mosaics; resilience and thresholds; biocomplexity; adaptive cycles; and in the landscape ecology of invasive spread.     

海南地区园林绿地中的观赏草资源及配置

观赏草由于其自然的形态、多样的色泽、独特的花(果)序、受到设计师的青睐,在海南地区园林绿地中应用日趋广泛。加之观赏草具有观赏期长、生命力强、养护成本低等优势,成为园林绿化的理想选择,在海南,从公园到街边,从单位到小区,从景区到酒店、高尔夫球场都能寻觅到它们的芳容。通过实地调查,发现目前在海南地区园林绿地中应用的观赏草资源大约有60种,其中包含了一些本地的野生资源。同时对海南地区各类型绿地中观赏草的配置和应用情况进行了分析和总结,并就当前存在的问题提出了建议,希望能为海南地区观赏草资源的进一步利用提供参考。     

南京下马坊遗址公园植物景观分析

以下马坊遗址公园为例,通过对公园植物的种类组成、空间结构、植物群落、季相变化、植物应用等方面调查,分析历史文化古迹中园林植物配置的特点及不足,并提出合理的优化建议。     

Modeling the Impact of Climate and Vegetation on Fire Regimes in Mountain Landscapes

Assessing the long-term dynamics of mountain landscapes that are influenced by large-scale natural and anthropogenic disturbances and a changing climate is a complex subject. In this study, a landscape-level ecological model was modified to this end. We describe the structure and evaluation of the fire sub-model of the new landscape model LandClim, which was designed to simulate climate–fire–vegetation dynamics. We applied the model to an extended elevational gradient in the Colorado Front Range to test its ability to simulate vegetation composition and the strongly varying fire regime along the gradient. The simulated sequence of forest types along the gradient corresponded to the one observed, and the location of ecotones lay within the range of observed values. The model captured the range of observed fire rotations and reproduced realistic fire size distributions. Although the results are subject to considerable uncertainty, we conclude that LandClim can be used to explore the relative differences of fire regimes between strongly different climatic conditions.     

The Forgotten Rural Landscapes of Central and Eastern Europe

Interactions between nature and man – the underlying forces in landscape – have over time caused diversity. Usually, geographers and landscape ecologists deal with spatial diversity; in this paper, we would like to also consider temporal diversity. We argue that Central and Eastern European landscapes (using the examples of Estonia, Hungary, Poland and Slovenia) are much more diverse in time (layers) than Western European ones. This difference requires the use of different indicators in order to measure and study landscapes and special problems, threats, and possibilities of management and future development – but most important is the consideration of different perceptions. We also show that this diversity reduces the readability of landscapes, creating miscommunication and a transformation of meanings. We further argue that the link between humans and landscape is lost in Central and Eastern European countries due to temporal diversity, and that this link will be created anew in a globalizing world. To overcome alienation, we need slightly different classifications/typologies for each country in this region, with the aim of a sound future management of cultural landscapes.     

生物菌肥在可持续农业中的应用

从生物菌肥的生产、在农业生产和有机物质生态循环中的作用等方面,简要介绍生物菌肥菌种、载体的选择,其在农业生产中改良土壤、促进植物生长、提高作物抗性、降低化肥农药危害、提高作物产量和品质,以及在有机物质生态循环中对城市生活和农业生产废弃有机物利用中的作用,并对生物菌肥在我国可持续农业中的应用做了展望。     

Connectivity in Heterogeneous Landscapes: Analyzing the Effect of Topography

Animal response to landscape heterogeneity directs dispersal and affects connectivity between populations. Topographical heterogeneity is a major source of landscape heterogeneity, which is rarely studied in the contexts of movement, dispersal, or connectivity. The current study aims at characterizing and quantifying the impacts of topography on landscape connectivity. We focus on ‘hilltopping’ behavior in butterflies, a dispersal-like behavior where males and virgin females ascend to mountain summits and mate there. Our approach integrates three elements: an individual-based model for simulating animal movements across topographically heterogeneous landscapes; a formula for the accessibility of patches in homogenous landscapes; and a graphical analysis of the plots of the simulation-based vs. the formula-based accessibility values. We characterize the functional relationship between accessibility values and landscape structure (referred to as ‘accessibility patterns’) and analyze the influence of two factors: the intensity of the individuals’ response to topography, and the level of topographical noise. We show that, despite the diversity of topographical landscapes, animal response to topography results in the formation of two, quantifiable accessibility patterns. We term them ‘effectively homogeneous’ and ‘effectively channeled’. The latter, in which individuals move toward a single summit, prevails over a wide range of behavioral and spatial parameters. Therefore, ‘channeled’ accessibilities may occur in a variety of landscapes and contexts. Our work provides novel tools for understanding and predicting accessibility patterns in heterogeneous landscapes. These tools are essential for linking movement behavior, movement patterns and connectivity. We also present new insights into the practical value of ecologically scaled landscape indices.     

Landscapes, sustainability and the place-based analysis of ecosystem services

There is currently, widespread interest in the assessment of ecosystem services, and the new insights that the concept provides in understanding the ecology of landscapes and the science of sustainability. Three major assessment frameworks can be identified in the contemporary literature, namely one based on habitats, one based on the identification of the system elements that delivers the service, and one based on the understanding of places. Although all are useful for supporting decision making in relation to sustainable development, different situations require different perspectives, and so it is important to understand their advantages and drawbacks. Moreover, it is important to determine how they relate to other approaches used, for example, in landscape planning, so that the contribution that ecosystem assessments can make to sustainability debates can be better understood. The aim of this paper is to describe the strengths of the place-based approach because it is more easily overlooked as an assessment option. In particular we will argue that a place-based approach can help us better understand issues of multi-functionality, the valuation of natural capital and the role of landscape in framing debates about ecosystem services and sustainability. An appreciation of these issues will enable researchers interested in landscape to key questions and priorities in relation to questions of sustainability. Although it is useful to consider different assessment perspectives separately, we conclude that in practice, the habitat and systems approaches can form part of a place-based assessment, just as a better understanding of place can enrich assessments that spring from these more natural science approaches. Nevertheless, in designing analytical strategies to take the ecosystem approach forward, we suggest that it is vital to consider these different perspectives in order to build assessments that are relevant, legitimate and credible, and which can effectively address the problems of sustainability that emerge at the landscape scale.     

Scale-Dependent Influence of Topography-Based Hydrologic Features on Patterns of Woody Plant Encroachment in Savanna Landscapes

Rainfall in drylands is erratic. Topographic features of landscapes can dampen or amplify temporal variability by spatially influencing patterns of water loss and accumulation. The extent to which portions of a landscape may differentially capture or retain scarce water and nutrient resources is an important determinant of vegetation patterns, particularly with respect to the distribution of woody plants. We therefore hypothesized that historic changes in woody cover on landscapes experiencing similar climate and disturbance regimes would vary with catena-to-catena (hillslope-to-hillslope) variation in topography-based hydrologic features. We tested this hypothesis by comparing topographic wetness index (TWI) values on replicate landscapes where woody plant abundance has increased over the past 100 yr. These landscapes are characterized by savanna parklands on coarse-textured upland portions of catenas that grade (1–3% slopes) into closed-canopy woodlands on fine-textured (lowland) portions of catenas. TWI values for woody and herbaceous communities were comparable within uplands, suggesting factors unrelated to surface/subsurface hydrology determine patterns of woody cover in these catena locations. TWI values for upland savanna parklands were significantly lower than those of closed-canopy woodlands occupying catena footslopes. Furthermore, uplands adjoining historically static woodland boundaries had lower TWI values than those where woodland boundaries had moved upslope 2.1 m yr⁻¹ from 1976 to 1995. Results suggest runoff–runon relationships influence patterns of woody plant cover and change at the catena scale and may override constraints imposed by soil texture. As a result, changes in woody cover potentially accompanying changes in disturbance regimes, climate or atmospheric chemistry are likely to be constrained by topoedaphic settings. Models of vegetation dynamics may therefore need to explicitly account for rainfall–topography–soil texture relationships and associated scale-dependent mechanisms to accurately predict rates and patterns of change in woody and herbaceous plant abundance.     

中国农业可持续发展水平研究

农业作为国民经济的基础性产业,与国家粮食安全、农村社会稳定发展与资源合理配置息息相关,对中国农业可持续发展水平研究具有重要意义。该研究采用主成分模糊综合评价法以1989—2018年为时间序列对中国农业可持续发展水平进行评价分析。结果表明:1989—2011年中国农业可持续性评价结果为差,波动性较大;2012—2018年评价结果为一般,较为稳定;总体上看,中国农业可持续发展水平持续提高,但处于一般水平,仍存在较大上升空间。鉴于此,从健全法律法规、完善农业扶持政策、加强农业可持续发展科学技术支撑能力等方面提供了促进农业可持续发展的建议,以期为提高农业可持续发展水平提供参考。     

城市森林植被对空气PM2.5质量浓度的影响

在北京大兴南海子公园内选取森林植被区,并分别对远离林带1、5、15、30、50m处的PM_(2.5)浓度进行全天连续监测,分析远离林带不同距离对PM_(2.5)浓度的影响及其日变化特征。结果表明:林内及距林带不同距离处PM_(2.5)日变化趋势相同,从早到晚均呈先降低后增加的趋势,PM_(2.5)浓度最小值出现在15:30左右,最大值出现在05:00—07:00;远离林带的距离对PM_(2.5)浓度有显著影响,随远离林带距离的增加,其浓度先降低而后增加,在距林带30m处PM_(2.5)浓度达到最低值,说明森林对颗粒物的削减作用最强。     

Characterizing Fine-scale Patterns of Alternative Agricultural Landscapes with Landscape Pattern Indices

Landscape pattern indices are common tools of landscape ecologists, affording comparisons of different study areas, or the same study area at different times. Since the advent of popular index-calculating software, more landscapes can be analyzed in short amounts of time, yet the behaviour of landscape pattern indices can vary for different contexts or data characteristics, complicating interpretation. I applied a selected set of landscape pattern indices to fine-resolution (3 m) data representing a highly fragmented landscape – Corn Belt Iowa agriculture – to investigate the performance of landscape pattern indices. Indices measured pattern attributes that affect the viability of small mammal populations, namely habitat proportion and connectivity and landscape grain size and heterogeneity. Results showed that the performance of indices for fine-resolution data can be highly variable, depending upon data and contextual issues like the presence of linear elements and the amount of habitat. For these Corn Belt landscapes good habitat proportions and patch sizes were small (commonly less than 10% and less than 1 ha, respectively), and connectivity was variable depending on the measure. Aggregation and mean nearest neighbour indices performed better than other connectivity indices. Fine-resolution data representing highly fragmented landscapes can raise difficulties for indices of landscape configuration. Landscape pattern indices require improvement to perform better for increasingly available fine-resolution data representing common landscape types.     

Green Veining: Landscape Determinants of Biodiversity in European Agricultural Landscapes

Many semi-natural landscape elements, the so-called green veining, are disappearing from the intensively used agricultural landscapes of Europe. In order to develop or restore biodiversity in these networks, it is necessary to quantify the relation between biodiversity and amount, spatial arrangement and management intensity of green veining elements. In this review, we investigate whether biodiversity increases with the amount of green veining in an agricultural landscape following the species–area relationship, and whether a certain level of biodiversity can be reached at lower densities of green veining if green veining elements are better connected (higher spatial connectivity) or if they are managed less intensively (lower management intensity). We reviewed studies on aboveground biodiversity in green veining structures in 39 scientific papers on field and experimental studies within Europe. More of these studies focussed on management intensity than on amount or spatial configuration of green veining. Also more studies focussed on the spatial scale of individual landscape elements than on the farm or landscape scale, which may be caused by the large number of studies focussing on plant or invertebrate species. Species living at larger spatial scales, e.g. mammals and birds were not often studied at the level of green veining elements as they also use agricultural fields as part of their habitat. We could not verify the species–area relation for green veining, nor the effect of amount, spatial configuration or management intensity on this relation, because only few studies quantified the found effects and no studies were found on the effect of management intensity or spatial configuration on the species–area curve in green veining. We addressed the most important challenges for future field and model research in order to fill the identified gaps in knowledge.