Integrating Multi‐Sensor Remote Sensing Data for Land Use/Cover Mapping in a Tropical Mountainous Area in Northern Thailand

Accurate mapping of land use/cover conditions provides essential information for managing natural resources and is critical for further examination of land use/cover change and its subsequent impacts on the environment. Remote sensing offers a means of acquiring land use/cover data in a timely manner, with optical remote sensing images commonly being used in land use/cover related studies. The persistent cloud cover during the rainy season in Southeast Asia, however, presents a challenge for using optical images in land use/cover mapping. Integrating multi‐sensor images of different spectral domains is thus desirable because more information can be extracted to improve the mapping accuracy. The purpose of this study is to assess the potential of using multi‐sensor data sets for land use/cover mapping in a tropical mountainous area in northern Thailand. Optical data from Landsat Thematic Mapper, radar images from Advanced Land Observing Satellite/Phased Array type L‐band Synthetic Aperture Radar (PALSAR), and topographical data were used, providing complementary information on land use/cover. Classification and accuracy assessment were conducted for 12 different combinations of the data sets. The results suggested that short crop mapping using multi‐temporal Phased Array type L‐band Synthetic Aperture Radar images offered insights into the distributions of crop and paddy fields. Because of the mountainous environment of the study area, combining topographic data of elevation and slope into the classification greatly reduced the confusion between different land use/cover types. Improvement of classification accuracy was evident especially in separating evergreen and deciduous forests from other vegetation types and discriminating urban village and the fallow field classes.     

From Simplicity to Complexity: The Changing Geography of Land Vulnerability to Degradation in Italy

Although territorial disparities in land quality are commonly observed in Mediterranean‐type ecosystems, how different geographical gradients impact the changing distribution of land vulnerable to degradation over time and space is poorly investigated in southern Europe. The present study assesses the spatial distribution of vulnerable land according to a composite index that describes the degree of land vulnerability to degradation in Italy along eight gradients during two time periods (1960–1990 and 1990–2010), representing distinct socio‐economic and environmental conditions. While the degree of land vulnerability increased at similar paces from 1960 to 1990 and from 1990 to 2010, the spatial distribution of vulnerable land changed considerably. From 1960 to 1990, the area of vulnerable lands increased in coastal areas, lowlands, and areas with moderately high population density, mainly owing to the increased climate aridity. By contrast, peri‐urban areas experienced, especially in northern Italy, the highest vulnerability from 1990 to 2010 owing to increased human pressure on land generating, e.g. land‐use changes. Results indicate that the importance of the gradients shaping the distribution of vulnerable land in Italy is reflected in the (changing) role of climate, vegetation cover, and human pressure as factors predisposing land to degradation. Finally, policy implications of the changing geography of vulnerable land in the Mediterranean region are discussed.     

Long-term agrarian landscapes in the Troodos foothills,Cyprus

We investigate the temporal and environmental relationships between the terraced hill slopes of Politiko-Koloiokremmos and the adjacent Bronze Age settlement of Politiko-Troullia in foothills of the Troodos Mountains, central Cyprus. Mapping of 102 stone walls on Koloiokremmos is compared with 66 walls farther afield on Cyprus to create a six-part terrace typology. Sherd counts from 174 2-m radius collection circles over approximately 20 ha on Troullia and Koloiokremmos were used to create interpolated sherd density surfaces revealing distinctly different patterns of land use for four major archaeological eras between the Cypriot Bronze Age and Medieval Period. We compared sherd density patterns according to terrace types, length, slope and vegetation cover determined by SAVI (Soil-Adjusted Vegetation Index) from Ikonos and Quickbird satellite imagery.The most robust sherd patterning indicates Prehistoric Bronze Age settlement at Troullia, as confirmed by soil resistivity and excavation, and multi-period land use on Koloiokremmos immediately upslope of the village that may be associated with agricultural terracing. Scattered sherd concentrations indicate later use of this landscape as an agricultural hinterland for the Iron Age city of Tamassos. Sherds and a down slope spread of roof tiles from the Roman through Medieval periods suggest an isolated structure near the crest of Koloiokremmos. Longer terraces correlate with greater vegetation cover and are interpreted as agricultural, while shorter terraces, apparently for erosion control and arboriculture, are significantly related to Prehistoric Bronze Age sherd patterns. Our results suggest that coordinated analysis of archaeological, geographical and remotely sensed environmental data associated with terraced landscapes can be used to infer long-term patterns of agricultural land use.     

Emprise et déprise de l'agriculture sur le territoire de l'est de l'Ontario de 1826 à 2006: la dimension environnementale

Agricultural land‐cover changes in Eastern Ontario from 1826 to 2006: environmental effects. Stormont, Dundas and Glengarry (SDG) counties, Eastern Ontario, are among the first areas in Ontario to welcome settlers. In 1784, they established themselves in a forested land where wetlands are very important. Today, a large part of the wetlands has disappeared, but the landscape is wooded, masking the radical changes that took place over the course of the last two centuries. Analysis of census data from 1826 to 2006 allows the reconstruction of the history of land‐cover changes. It reveals the nature and rates of change for which a first analysis is presented. Four periods are identified. First, agriculture conquers the land and establishes its dominance. A plateau is reached in 1891 as agriculture maintains its supremacy until 1941. Then, as fast as agriculture invaded land, it fades away until 1986 when agricultural land‐cover stops shrinking. The opening of forest for cultivation was relatively slow in SDG because of biophysical and socio‐economical conditions associated with an absence of growth of agricultural population. Deforestation and wetland drainage led to a degradation of agricultural life but resulted in consideration of the environment in agriculture. Today, wooded and agricultural land covers are more balanced and environmental effects less acute.     

Dynamics of Land Surface Temperature in Response to Land‐Use/Cover Change

In this study, we employed Geographical Information Systems and remote sensing techniques to investigate the impact of land‐use/cover change on land surface temperature (LST) in a rapidly urbanisation city, Kunming in south‐west China. Spatial patterns of LST and land use for 1992 and 2006 were derived from Landsat images to examine how LST responded to urban growth. Remote sensing indices were used to quantify land‐use types and employed as explanatory variables in LST modelling. The geographically weighted regression (GWR), a location dependent model, was performed to explore the influences of the spatially varied land‐use conditions on the LST patterns. Results revealed that rapid urbanisation in Kunming altered the local thermal environment, particularly in increasing the LST in the zone surrounding the urban core. Remote sensing indices demonstrated that water and vegetation played an important role in mitigating the urban heat island effect, while built‐up and barren land accounted for the increase in LST. The GWR improved the goodness‐of‐fit for LST modelling and provided insights into the spatially varied relationship between LST and land‐use conditions.     

The Role of Geographers in Work on a Land Cadaster and on an Agricultural Evaluation of Lands

Geographers have been in the forefront of the campaign to institute a full-fledged land cadastre and economic land-evaluation program in the Soviet Union. Although a State Register of Landholdings was adopted in 1955, it is concerned mainly with the distribution of lands among land-holdings and the composition of agricultural lands (crop land, hay meadows, pastures, etc.) within landholdings. A full fledged cadastral and evaluation program would seek to evaluate land in terms of quality and productivity. In view of the interdisciplinary character of the work, geographers are viewed as most suitable participants.     

Monitoring Land‐Cover and Land‐Use Change in a Rapidly Urbanising Coastal Environment: the Maroochy and Mooloolah Rivers Catchments,Southeast Queensland, 1988–1997

Effective catchment monitoring requires an integrative approach for selecting remotely sensed data to monitor land‐cover change. Catchment analyses and monitoring requirements in the Maroochy and Mooloolah River Catchments (south‐east Queensland) were addressed by linking government and community information needs to appropriate scales of remotely sensed data and processing routines. A hybrid image classification approach applied to Landsat Thematic Mapper image data acquired in 1988 and 1997 provided catchment scale land‐cover maps (with accuracies of 73% and 84%). Land‐cover change maps derived from post‐classification comparison provided information on the spatial distribution and type of land‐cover changes between 1988–1997. Land‐cover change was dominated by activities related to urban residential expansion (suburban and rural residential) and agricultural expansion (sugar cane farms). Significant spatial variations in the geometric registration accuracy of the image data sets and classification accuracies produced moderate to low change detection accuracies. However, the framework and community consultation used for selecting and processing data ensured the resource managers and community groups were fully aware of the limitations of the land‐cover change mapping process and that the output images were suitable for incorporating in resource monitoring activities.     

Application of Landsat satellite imagery to monitor land‐cover changes at the Athabasca Oil Sands,Alberta, Canada

A major advantage of satellite remote sensing is that the imagery acquired provides a synoptic view of the landscape. Thus, repeat coverage by the satellite on a regular basis permits the detection of changes in land‐cover over time. This study demonstrates the application of remote sensing technology to the monitoring of mining activities at the Athabasca Oil Sands region of Alberta, Canada. First, we describe the techniques used to match a time sequence of Landsat imagery, both spatially and spectrally, to ensure that the spectral changes through time are due to land‐cover variations. A series of spectral trajectories were then extracted to assess changes in land‐cover through time. Secondly, a land‐cover classification was produced from the baseline 1984 imagery and, using historic and future mine extents, the classification was analyzed to determine the proportion of each land‐cover type affected through development. Results of the analysis indicate that since 1984 there has been a larger reduction in mixedwood dense and broadleaf vegetation classes than mixedwood sparse or dense conifer stands in the area. Based on the delineations of mine‐site activity, the area of woodland and wetland habitat subject to development has increased from approximately 2,520 hectare (ha) in 1984 to 32,930 ha in 2005.     

Spatial pattern of land cover changes across Northeast China over the past 300 years

To accurately model the regional climatic effects of land use/cover change processes, precise reconstructions of historical land cover are essential. Over the past 300 years, the northeastern region has undergone more significant land cover change than any other region in China owing to large numbers of farmer migrants from North China, reflecting the tremendous effects human activities can have on such changes. In this paper, based on official statistical data, documentary records, survey data, and modern remote-sensing data and vegetation and soil maps, land cover changes across Northeast China over the past 300 years have been reconstructed through cropland data calibrations using correlation analysis, potential vegetation reconstructions, urban area estimations, spatial analyses of land cover type changes by K-mean clustering analysis, and consideration of land use driving forces. The results indicate that cropland expanded gradually from south to north through the cities of Shenyang, Jilin, and Ha’erbin as well as out to the margins of the central plain of Northeast China, with a maximum expansion occurring in the 1950s. Pristine forests and grasslands diminished significantly, especially in the early twentieth century, due to this expansion of cropland. The conclusions drawn from these results are, first, that these results provide a scientific understanding of the process by which the original land cover was replaced by cropland in Northeast China over the past 300 years. Second, the results enabled the development of a series of land use/cover changes maps with 50–100 year time resolutions and county-level spatial resolutions. Based on the reconstructed results of these land cover type changes, the dynamics and causes of land cover changes are discussed in their social–historical contexts.     

Measuring biological heterogeneity in the northern mixed prairie: a remote sensing approach

Biological heterogeneity, defined as the degree of dissimilarity between biological variables (e.g., biomass, green vegetation and Leaf Area Index [LAI]), is one of the most important and widely applicable concepts in ecology due to its close link with biodiversity. To investigate grassland biological heterogeneity, we selected three transects extending from upland to valley grasslands at Grasslands National Park (GNP), Canada, representing the northern mixed grassland. For the purposes of our analysis, three types of data were collected: remote sensing ground level hyperspectral data, biological data (LAI, biomass, and vegetation cover) and environmental data (soil moisture, organic content, and bulk density). Methodologically, field-level remote sensing data were used to calculate spectral vegetation indices. These indices, plus the biological variables, were then used in regression analyses with the goal of assessing the feasibility of using remote sensing data to study biological heterogeneity. The results indicate that it is feasible to use ground-level remote sensing data to represent biological variables. These indices can explain about 40–60 percent of the biological variation. Semivariogram analyses were further applied on these data to investigate their range of spatial variation. Spatial variations in the     

Applying a Systematic Review to Land Use Land Cover Change in Northern Upland Vietnam: The Missing Case of the Borderlands

As Vietnam embraces the market economy, and a number of state policies promote reforestation and rural market integration, land use and land cover (LULC) changes are occurring in the country's northern uplands in increasingly complex and fragmented ways. Yet understandings of the degree and consequences of LULC changes in this diverse agro‐ecological region are incomplete. We conduct a systematic literature review of research reported in academic articles tracing and analysing LULC change in Vietnam's northern regions. We find that these studies have tended to take place away from the most mountainous, northern borderlands. The studies nonetheless highlight a diversity of land use land cover changes caused by numerous causes, making the distinction of overall trends difficult. To complement and extend this body of research, we introduce recent LULC change research we have completed in the mountainous border districts of Lào Cai province, on the Sino‐Vietnamese border. The heterogeneity of causes of LULC change in both the review articles and our case study points to the importance of adapting land use policies to local agro‐ecological and socio‐economic conditions and ethnic diversity, taking into account state–farmer relations, household livelihood decision‐making, and policy implementation at the commune and district levels.     

Fringe explosions: risk and vulnerability in Canada's new in‐between urban landscape

This article argues that a new landscape of urbanization takes shape in Canadian cities. In‐between the old downtowns and the new suburbs of urban Canada, a hitherto underexposed and under‐researched mix of residential, commercial, industrial, educational, agricultural and ecologically protected areas and land uses has become the home and workplace, and increasingly also the playspace of most people in Canada. The article examines this new landscape through the lens of the specific risks and vulnerabilities experienced by its inhabitants and users. Using a propane gas explosion in Toronto in the summer of 2008 as an example, we demonstrate that the ‘in‐between city’ is a space of great complexity, which has grown haphazardly and in a contradictory fashion, where, in contrast to the archetype of inner city and suburb, no clear spatial imaginary has been guiding urban development. This leads to always uncomfortable and sometimes dangerous proximities between various and competing uses and social practices. This is nowhere as clear as it is in the splintered urban infrastructures that service this landscape or use the in‐between city's space to service other adjacent or distant purposes.     

Developing a Synthetic Index of Land Vulnerability to Drought and Desertification

This paper develops an index of the vulnerability of land to drought and desertification (LVI) for Italy. The index takes into account changes in climate, land use, vegetation cover, soil properties, and population during the period 1990–2000. The LVI was built up through a multivariate approach aimed at assessing the importance of the various indicators included in the synthetic index. Increasing land vulnerability was observed during this time, especially in dry areas of the southern regions. This is interpreted as a consequence of land management practices, agricultural intensification, population pressure, and bio-physical degradation. The LVI can be used in an integrated, decision-support system to evaluate the impact of mitigation policies in rural environments.     

NDVI variation and its relation to climate in Canadian ecozones

Parks Canada began the Northern Satellite Monitoring Program in 1997, with the objective of tracking large‐scale vegetation variation in Canadian ecosystems and helping land managers to develop appropriate management practices in response to climate change. Under this program, a sequence of 10‐day composite Advanced Very High Resolution Radiometer (AVHRR)‐derived Normalized Difference Vegetation Index (NDVI) data from 1985 to 2007 was examined to study seasonal and inter‐annual relationships between vegetation and climate data over Canadian ecosystems using statistical and wavelet analysis. Statistical analysis showed that temperature was the principal driver for seasonal variability in greenness, explaining more than 70 percent of seasonal variation in vegetation for most Canadian ecozones. In comparison with temperature, the relationships between NDVI and precipitation were weaker but still significant. Maximum annual NDVI showed increasing trends in Canadian ecozones during the study period, although increasing rates were spatially heterogeneous. Wavelet analysis confirmed that inter‐annual variation in NDVI was different at two ecozones in Canada. NDVI variation in the Northern Arctic was significant at scales of 3–4 years from 1997 to 2001, which was associated with temperature and precipitation variation. Comparatively, NDVI variation in the Boreal Shield was significant at scales of 5–8 years from 1991 to 1999, but did not correspond with climate variation.     

Payments for Ecosystem Services in Nicaragua: Do Market‐based Approaches Work?

The concept of Payments for Ecosystem Services (PES) is gaining increasing attention among scholars as well as conservation and development practitioners. The premises of this innovative conservation approach are appealing: private land users, usually poorly motivated to protect nature on their land, will do so if they receive payments from environmental service buyers which cover part of the land users’ opportunity costs of developing the land. However, this article warns against an over‐enthusiastic adoption of a one‐sided market‐based PES approach. Based on a field study of the Regional Integrated Silvopastoral Approaches to Ecosystem Management Project (RISEMP), one of the main PES pilot projects in Nicaragua, it suggests that a mixture of economic and non‐economic factors motivated farmers to adopt the envisaged silvopastoral practices and that the actual role of PES is mistakenly understood as a simple matter of financial incentives. The authors argue that PES approaches should be understood as a part of a broader process of local institutional transformation rather than as a market‐based alternative for allegedly ineffective government and/or community governance.     

SPACE,PRESSURES AND THE MANAGEMENT OF THE GREEK LANDSCAPE

Landscapes are the result of the interaction of natural and human factors, with many dimensions; they are part of natural and cultural heritage and an important component of the quality of life. Greece has heterogeneous and mixed landscapes issuing from both geomorphology and the impact of complex human systems. Despite the existence of many and early legislative efforts, Greece has a relatively poor history of spatial planning and landscape has been particularly neglected. The adoption of the European Landscape Convention (ELC) in 2010 provides an updated strategic context for integrating landscape in spatial planning. In this article, we seek to contribute to the discussion of landscape policies and the inclusion of the landscape level in the spatial planning national framework. We identify the dominant landscape types by categorizing landscapes at the national scale with reference to the (combined) presence of three different components: geomorphology, land cover and coasts/islands. Then, we investigate the most important processes of change for each type and link these processes with spatial planning policy. The identification of these dynamics sheds light on current and future trajectories of the changes of Greek landscapes, thus providing challenges for its management in the context of the ELC. The case study concerns the regional level; we focus on Attica, Thessaly, Epirus and the Cyclades and identify the principal characteristics according to the proposed landscape typology.     

2001-2008年无锡市土地利用景观格局变化分析

无锡市作为位于长江三角洲地区的核心地域,2000年实施新城市化战略以来城市化水平大幅上升,但对这一时期无锡市土地利用景观变化的研究相对较少。本文从景观生态学的角度研究无锡市2001-2008年间的土地利用景观变化,发现无锡市的土地利用变化速率较快,且递减最快的为耕地,而递增最快的为建设用地及园地;无锡市2000年之前景观格局基本构型以大斑块为主,景观格局较为单一,但2001-2008年该地区剧烈的人类活动使得这些大斑块发生破碎化,导致不同景观类型的斑块数量不断增加,各类用地所占比例的差异逐步减少。总体上看,无锡市的景观多样性在增加,景观优势度在减少。     

关注遗产保护的新动向:文化景观

文化景观这一概念在景观生态学、文化地理学、人类生态学等学科中历史悠久,并被广泛应用。作为世界遗产体系中的文化景观,是人与自然相互作用的杰作,在二十世纪九十年代刚刚出现,但它已经成为遗产保护和利用领域中的热点。文化景观概念可以更好地理解遗产保护中的真实性和完整性原则,其重点在于保护人与自然互动的过程和产物,涉及到空间过程与土地利用、地形、水文、植被、交通、细部结构与装饰、健康与环境等方面。在中国倡导文化景观这一概念对于整个遗产的保护、生态的维系、文化的延续、旅游的开发、经济的发展都具有十分重要的作用。