Dynamic modeling of forest conversion: Simulation of past and future scenarios of rural activities expansion in the fringes of the Xingu National Park,Brazilian Amazon

The present work is committed to simulate the expansion of agricultural and cattle raising activities within a watershed located in the fringes of the Xingu National Park, Brazilian Amazon. A spatially explicit dynamic model of land cover and land use change was used to provide both past and future scenarios of forest conversion into such rural activities, aiming to identify the role of driving forces of change in the study area. The employed modeling platform – Dinamica EGO – consists in a cellular automata environment that embodies neighborhood-based transition algorithms and spatial feedback approaches in a stochastic multi-step simulation framework. Biophysical variables and legal restrictions drove this simulation model, and statistical validation tests were then conducted for the generated past simulations (from 2000 to 2005), by means of multiple resolution fitting methods. Based on optimal calibration of past simulations, future scenarios were conceived, so as to figure out trends and spatial patterns of forest conversion in the study area for the year 2015. In all simulated scenarios, pasturelands remained nearly stable throughout the analyzed period, while a large expansion in croplands took place. The most optimistic scenario indicates that more than 50% of the natural forest will be replaced by either cropland or pastureland by 2015. This modeling experiment revealed the suitability of the adopted model to simulate processes of forest conversion. It also indicates its possible further applicability in generating simulations of deforestation for areas with expanding rural activities in the Amazon and in tropical forests worldwide.     

Analyzing the effects of scale and land use pattern metrics on land use database generalization indices

The generalization index system is one of the critical issues for computer-aided land use database generalization. This paper studies the scale and land use pattern effects on land use database generalization indices and estimates the thresholds of these indices based on a typical land use database sample. The index system of land use database generalization is discussed and constructed from macro and micro perspectives. Six land use pattern metrics, namely, land use diversity index, land use dominance index, land use homogeneity index, land use fragmentation index, the index of land use type dominance, and the index of land use type fragmentation, are designed to characterize land use patterns and are introduced into the analysis of land use pattern effect on land use database indices. The analysis framework of the scale and land use pattern effects on the land use database indices are proposed by employing statistical techniques. Based on the land use database samples at multiple spatial scales collected in various land use regions across China, the study generates rules for both scale and land use pattern effects on the indices, including map area proportion of land use types, total map load, parcel map load, and minimum parcel area. The thresholds of these indices in land use database generalization are produced at the scales of 1:50,000, 1:100,000, 1:250,000, and 1:500,000. An experimental generalization at county level demonstrates how to determine the generalization index values considering scale and land use pattern, and how to evaluate the generalization results using our macro indices.     

How natural disturbance triggers political conflict: Bark beetles and the meaning of landscape in the Bavarian Forest

The incidence of natural disturbance in forests is increasing globally as a consequence of global warming. The concomitant large-scale transformation of landscapes can have profound social impacts and trigger political conflict that hampers resource management. This paper explores the link between landscape transformations and political conflict using the example of the bark beetle epidemic in Bavarian Forest National Park, Germany. For a significant part of the local population, the bark beetle represented a threat to their homeland and the post-disturbance landscape of dead wood reflected the dominance of outside interests in land management. This resentment sparked the formation of a local political movement, which was successful in pressing for changes in the current land management policy that were based on the ideal of a green forest landscape that needed to be protected by human intervention. An alternative interpretation of the post-disturbance landscape, however, welcomed it as a step towards authentic wilderness and opposed interventions to control the bark beetle. These contrasting understandings of the post-disturbance landscape underpin the protracted political conflict over the appropriate management of natural disturbance that has been smouldering for more than 20 years. The article concludes that it is vital to understand the cultural meaning of landscapes before adopting a disturbance management policy in order to avoid paralysing political conflict and social unrest.     

The concept of cryo-conditioning in landscape evolution

Recent accounts suggest that periglacial processes are unimportant for large-scale landscape evolution and that true large-scale periglacial landscapes are rare or non-existent. The lack of a large-scale topographical fingerprint due to periglacial processes may be considered of little relevance, as linear process-landscape development relationships rarely can be substantiated. Instead, periglacial landscapes may be classified in terms of specific landform associations. We propose “cryo-conditioning”, defined as the interaction of cryotic surface and subsurface thermal regimes and geomorphic processes, as an overarching concept linking landform and landscape evolution in cold regions. By focusing on the controls on processes, this concept circumvents scaling problems in interpreting long-term landscape evolution derived from short-term processes. It also contributes to an unambiguous conceptualization of periglacial geomorphology. We propose that the development of several key elements in the Norwegian geomorphic landscape can be explained in terms of cryo-conditioning.     

高架轨道交通对城市景观的影响及应对措施初探

论文分析了高架轨道交通对城市景观的双重影响:高架桥作为一种新的城市构筑物,为人们提供了欣赏城市的新的观赏点和观赏方式;但处理不当的高架构筑物具有破坏自然景观、影响人们的视觉、造成尺度失调、影响城市色彩和谐、破坏城市原有肌理等负面影响。进而论文提出了高架轨道交通的设计原则及改善轨道交通城市形象的应对措施:第一,巧妙选线,充分利用轨道交通沿线风景资源,形成轨道交通视觉廊道;第二,提升高架桥的空间景观形象:桥下空间综合利用,完善城市功能;桥侧空间精心设计,增强桥体人性化因素;重视高架桥体及附属物的形象设计,达到技术与艺术的完美统一;第三,建设具有地域风格的换乘站。     

从建筑空间处理的典例看园林艺术的魅力

一个成功的建筑空间与园林艺术设计,会给观赏者带来视觉和美的享受,建筑空间与园林艺术的有机结合,产生的魅力是无穷的。本文通过介绍保利花园的设计理念,反映出设计是生活体验的演绎,"以人为本"的园林艺术设计在保利花园中获得成功。人文环境是设计师在设计中必须考虑的重要环节,设计师不仅可为人类提供满足功能需要的环境,还会给人们带来一种愉悦的情感体验,让人们看到了园林艺术的魅力。     

龙虎山丹霞地貌危岩景观成因及保护

龙虎山地处江西省东北部鹰潭市境内,据鹰潭市区10 km,是以丹霞地貌景观为特色的世界地质公园.龙虎山丹霞地貌主要以砂岩、砾岩、泥岩等岩层组成,岩壁陡峭,节理错综,发育众多外形奇特,有突出的旅游观光及美学欣赏价值的不稳定岩体,即危岩景观.龙虎山危岩景观经历了漫长的地质演变过程,是多因素耦合作用的结果,其主要影响因素有地形地貌、地层岩性、构造应力及水文地质条件以及雕蚀作用(包括流水侵蚀溶蚀、温度差异风化、微观化学风化等),其中雕蚀作用是危岩景观形成的核心要素.危岩景观保护须符合不破坏性、相近性、可逆性、无干扰性及如旧性五大原则.在分析现有危岩防治技术及危岩景观特殊性的基础上,提出吊索法保护危岩景观,即由绳索、钢索等能提供一定向上拉力,使危岩体达到要求的稳定系数的一种方法.吊索法具有适用范围广,理论计算简单,能较好提高稳定系数,施工方便,后续维修方便和易监测等诸多优点,适用于各类岩质景观的保护.     

综合型人工景观湿地在住宅小区中的应用

从住宅小区的生活污水生态化处理与环境景观园林化的角度,把综合型人工景观湿地引入住宅小区,将生活污水生态处理与园林景观建设高度融合。在营造人文景观时,以园林的造园手法,体现园林景观特征,具有审美、文化娱乐、休憩等综合功能。     

Characterizing bi-temporal patterns of land surface temperature using landscape metrics based on sub-pixel classifications from Landsat TM/ETM+

Landscape patterns in a region have different sizes, shapes and spatial arrangements, which contribute to the spatial heterogeneity of the landscape and are linked to the distinct behavior of thermal environments. There is a lack of research generating landscape metrics from discretized percent impervious surface area data (ISA), which can be used as an indicator of urban spatial structure and level of development, and quantitatively characterizing the spatial patterns of landscapes and land surface temperatures (LST). In this study, linear spectral mixture analysis (LSMA) is used to derive sub-pixel ISA. Continuous fractional cover thresholds are used to discretize percent ISA into different categories related to urban land cover patterns. Landscape metrics are calculated based on different ISA categories and used to quantify urban landscape patterns and LST configurations. The characteristics of LST and percent ISA are quantified by landscape metrics such as indices of patch density, aggregation, connectedness, shape and shape complexity. The urban thermal intensity is also analyzed based on percent ISA. The results indicate that landscape metrics are sensitive to the variation of pixel values of fractional ISA, and the integration of LST, LSMA. Landscape metrics provide a quantitative method for describing the spatial distribution and seasonal variation in urban thermal patterns in response to associated urban land cover patterns.     

Forest inventories by LiDAR data: A comparison of single tree segmentation and metric-based methods for inventories of a heterogeneous temperate forest

Inventories of temperate forests of Central Europe mainly rely on terrestrial measurements. Rapid alterations of forests by disturbances and multilayer silvicultural systems increasingly challenge the use of conventional plot based inventories, particularly in protected areas. Airborne LiDAR offers an alternative or supplement to conventional inventories, but despite the possibility of obtaining such remote sensing data, its operational use for broader areas in Central Europe remains experimental. We evaluated two methods of forest inventory that use LiDAR data at the landscape level: the single tree segment-based method and an area-based method. We compared a set of structural forest attributes modeled by these methods with a conventional forest inventory of the highly heterogeneous forest of the Bavarian Forest National Park (Germany), which partially includes stands affected by severe natural disturbances. Area-based models were accurate for all structural attributes, with cross-validated average root mean squared error ranging from ∼3.4 to ∼13.4 in the best modeling case. The coefficients of variation for the mapped area-based estimations were mostly minor. The area-based estimations were varied but highly correlated (Pearson’s correlations between ∼ 0.56 and 0.85) with single tree segmentation estimations; undetected trees in the single tree segmentat-based method were the main sources of inconsistency. The single tree segment-based method was highly correlated (∼ 0.54 to 0.90) with data from ground-based forest inventories. The single tree-based algorithm delivered highly reliable estimates for a set of forest structural attributes that are of interest in forest inventories at the landscape scale. We recommend LiDAR forest inventories at the landscape scale in both heterogeneous commercial forests and large protected areas in the central European temperate sites.